Superparamagnetic Iron Oxide Nanoparticles in Cancer Therapy: History
View Latest Version
Please note this is an old version of this entry, which may differ significantly from the current revision.
Contributor:
Thomas Vangijzegem
,
Valentin Lecomte
,
Indiana Ternad
,
Levy Van Leuven
,
Robert N. Muller
,
Dimitri Stanicki
,
Sophie Laurent

Despite significant advances in cancer therapy, its complex pathological process still represents a major health challenge when seeking effective treatment and improved healthcare. With the advent of nanotechnologies, nanomedicine-based cancer therapy has been widely explored as a promising technology able to handle the requirements of the clinical sector. Superparamagnetic iron oxide nanoparticles (SPION) have been at the forefront of nanotechnology development since the mid-1990s, thanks to their former role as contrast agents for magnetic resonance imaging. Though their use as MRI probes has been discontinued due to an unfavorable cost/benefit ratio, several innovative applications as therapeutic tools have prompted a renewal of interest. The unique characteristics of SPION, i.e., their magnetic properties enabling specific response when submitted to high frequency (magnetic hyperthermia) or low frequency (magneto-mechanical therapy) alternating magnetic field, and their ability to generate reactive oxygen species (either intrinsically or when activated using various stimuli), make them particularly adapted for cancer therapy.

  • iron oxide nanoparticles
  • SPION
  • cancer therapy
  • drug delivery

1. Introduction

A substantial number of studies on the use of SPION for various types of cancer-related therapies using various cell death mechanisms were proposed. Current chemotherapeutic drugs suffer from a lack of specificity, indiscriminately causing damage to both healthy cells and cancerous cells. Associating drugs with nanocarriers such as iron oxide nanoparticles has proven to be an efficient method to overcome the drawbacks of chemotherapy, while providing a way to follow the drug release by MRI as well as to trigger the release thanks to various stimuli. Iron oxide nanoparticles can generate mechanical forces or heat upon exposure to an alternating magnetic field (AMF) at either low frequency or high frequency, respectively, thereby inducing destructive effects on tumor tissues. Another characteristic feature of SPION which is consistently gaining attention is their ability to produce reactive oxygen species (ROS) through the iron-catalyzed Fenton and Haber–Weiss reactions.
In a biological medium, the Haber–Weiss’ reaction is considered thermodynamically unfavorable in the absence of any catalyst but can generate highly reactive radicals (OH•) by the iron-catalyzed Fenton reaction. Indeed, a reaction between hydrogen peroxide (H2O2) and iron (II) (Fe2+) leads to the formation of hydroxide (OH−) and hydroxyl radicals (OH•) in the Fenton’s reaction (Equation (2)), whereas the Haber–Weiss reaction leads to the generation of hydroxyl radicals and hydroxide from an iron-catalyzed reaction between H2O2 and the superoxide ion (Equations (1)–(3)) [1]:
Fe3+ + O2− → Fe2+ + O2
Fe2+ + H2O2 → Fe3+ + OH− + OH•
O2− + H2O2 → OH− + OH• + O2
Such ROS are well-known for their tremendous importance in the regulation of the tumor micro-environment (TME). Production of ROS induced by cell exposure to iron oxide nanoparticles, either alone or catalyzed using light (UV-visible or infrared light) or ionizing radiation (X-rays, protons, etc.), is a promising approach which can be used for cancer treatment.

2. Drug Delivery

Nowadays, the control of drug delivery to localized targets has become a major focus of biomedical research, especially in the field of cancer therapy [2][3]. Many nanosystems have been proposed as nanocarriers, and magnetic nanoparticles (i.e., magnetite and maghemite; SPION) appear as one of the most promising thanks to their biocompatibility and (super)paramagnetic properties, such as magnetic properties allowing for the combination between imaging modalities and specific release of drugs using either local (i.e., pH, conjugation of biomarkers, …) or external stimuli (i.e., external magnetic field).
The use of an image-guided drug delivery system is expected to provide a visualization of the spatial distribution of drugs and monitor its effective accumulation within tissues, possibly allowing for real-time adjustments of delivered doses in order to remain within the therapeutic window. The benefits of these non-invasive strategies are numerous and include improved treatment efficacy and reduced side effects. Most of the studies proposed the use of MRI [4][5][6][7] as a monitoring technique, and some recent reports mention Magnetic Particle Imaging (MPI) as a promising alternative. As SPION tracers are exogenous, this imaging technique has nearly no background in comparison with contrast-modified MRI [8][9]. The signal arising from SPION can be processed to reflect their spatial location and concentration, opening the doors for quantitative imaging with good spatial resolution (≈1 mm) and sensitivity (≈100 µM Fe) [10][11]. The use of MPI was proposed by Jung who developed olaparib-loaded exosomes as a platform for drug delivery to hypoxic cancer cells [12]. In another study, Liang developed apoptosis-specific tracer (Alexa Fluor 647-AnnexinV tagged SPION) and used MPI to accurately detect and quantify apoptotic tumor cells [13]. Using an MPI scanner, they could evidence a proportionality between the imaging signal and the number of apoptotic cells. Zhu [14] designed DOX-loaded SPION/poly(lactide-co-glycolide acid) (PLGA) core-shell nanocomposite as a drug delivery system. In their work, a good correlation between the nanoparticle-induced change in MPI signal and the release rate of DOX over time upon acidolysis was found, establishing quantitative monitoring of the release process in cell culture.
Passive targeting of solid tumors with nanoparticles is based on the assumed vascular permeability of the tumor microenvironment (i.e., by EPR effect) [15][16][17][18]. However, some reports highlight an inefficient process with tumoral accumulation of around one percent of the injected dose, even for xenograft tumors [19]. To improve the uptake and/or the accumulation, active targeting strategies have been explored through the attachment of antibodies, aptamers, or peptides to the nanocarrier surface. Such tumor-targeted strategies are expected to have limited impact on healthy tissues, resulting in higher therapeutic efficacy and lower toxicity. Nosrati provided a pyoverdine-based SPION and bound them to MCU1 aptamer as a DOX-delivery system [20]. In vivo studies highlighted significant tumor inhibition and survival rate in the mice receiving a single-dose aptamer-SPION in comparison with the non-targeted particles. In another study, Jia et al. prepared glioma-targeted vesicles by incorporating SPION and curcumin (Cur) into exosomes modified with neuropilin-1-targeted peptide (RGERPPR, RGE) [21]. Along with strong loading capacities, these natural vesicles [22] are able to cross the blood–brain barrier (BBB). When administered to orthotopic glioma models, they found promising results for targeted imaging and therapy of glioma, highlighting a potent synergistic antitumor effect between MHT and cur-mediated therapy. In their work, de Lavera et al. noted a synergetic effect in vitro when combining both the ligand neuregulin and a bispecific antibody fragment to SPION [23]. They proposed their system as a good alternative for administering camptothecin. Recently, specific drug delivery using the membrane of cancer cells, specifically that of homologous tumors, has emerged as a promising targeting method [6]. This bio-inspired strategy showed great potential for targeting specific tumors by adjusting the corresponding type of modified cell membrane. Zhu proposed a theranostic platform based on SPION covered with cracked cell membrane derived from a specific tumor type [24]. A combination with DOX showed strong potency for tumor treatment in vivo. A similar strategy was proposed by Meng for the specific delivery of peptides (namely PD-L1 inhibitory peptide and MMP2 substrate peptide) [25]. They showed superior targeting capacities with TPP1 peptide being delivered and released to the tumor microenvironment through the homotypic effect of tumor cell membrane and specific digestion by the tumor-specific enzyme MMP2.
It is believed that the percentage of drug release in a specific location can be increased by using stimuli-responsive systems [26][27][28]. A common strategy is to take advantage of the pH difference between tumoral (slightly acidic) and healthy tissues. As a result, strategies implying the use of pH-sensitive bonds (e.g., hydrazone) or pH-sensitive coatings (e.g., polymers) were developed [29]. An interesting releasing approach was proposed by Liu and collaborators who developed mesoporous silica-coated SPION with programmable DNA hairpin sensor «gates» as tumor-cell-specific drug delivery systems [30]. Drug release was promoted by endogenous miRNA-21 overexpressed in tumor cells (HepG2, human liver tumor cells), which served as a specific key to unlock the system through hybridization with programmable DNA hairpin. Cai developed a reduction and pH dual-sensitive targeted (anti-glypican-3 antibody) polymeric micelles incorporating sorafenib and SPION for the treatment of hepatocellular carcinoma [31]. The efficiency of the nanocarrier was shown in vivo to display prominent anticancer effects and a low systemic side effect in an animal study (mice baring subcutaneous HepG2 xenograft). To reduce the side effect of paclitaxel and enhance its accumulation at the tumoral site, Ding prepared a novel redox-responsive magnetic nanocarrier based on disulfide-linked amphiphilic polymer [32]. The nanocarrier significantly improved intracellular uptake and enhanced tumoral accumulation, with an effective inhibition of tumor cells in vitro and in vivo through sensitive redox response, resulting in effective PTX release.
Taking advantage of the magnetic properties of iron oxide nanoparticles, some groups proposed site-specific drug delivery by inducing SPION accumulation by the action of a localized external magnetic field. In this context, SPION can be used either as individual nanoparticles (i.e., monocore systems [33]; in that case the magnetic response of SPION depends on their physicochemical properties, more specifically, their saturation magnetization which must be as high as possible) or as magnetic nanoassemblies encapsulated in macromolecular matrices (i.e., multicore systems) [34]. SPION organization within stabilized nano/micro-assemblies appears as a promising strategy to reach efficient response toward an external magnetic stimulus. For example, Qi et al. recently designed a reticulocyte (RTC) exosomes-based SPION clustering strategy for tumor-targeted drug delivery [22]. The tumoral magnetic-targeting ability was shown in vivo using Cy5.5-labelled SPION-exosomes through a significant increase of the fluorescence signal at the tumoral area when an external magnetic field (1 T) was applied. Micro/nano-scale robots [35] can effectively convert magnetic energy into locomotion [36] and can be used to support drug delivery vehicles, particularly in the case of cancer [37]. Recent progress of untethered mobile micromotors highlighted huge potential for targeted drug delivery in vivo. In the particular case of cancer treatment, Kim and co-workers proposed a hydrogel sheet-type magnetic retrieval intraocular microrobot for the treatment of retinoblastoma [38]. The developed system was made of a therapeutic layer of gelatin/PVA composed of PLGA–DOX drug particles and a SPION layer composed of PEGDA containing SPION. The potential for the vitreous migration of the microrobot and the therapeutic effect against retinoblastoma Y79 cancer cells was shown using ex vivo bovine vitreous and in vitro cell tests.

3. Magnetically Activated Therapy

In recent years, it has been demonstrated that SPION’s magnetic properties can be modulated through their shape and composition, so that they can be mechanically actuated, attracted to a region of interest, or used to generate a local heating. This is of particular interest in the context of mechanobiology, where SPION can be used to apply local forces on biological specimens using extremely low frequency magnetic field (ELMF) and to study the cellular response of tumor cells. Destroying cancerous cells or tumors through magneto-mechanical effect is a growing field of research. The desired effect is reached by means of low frequency mechanical vibrations of SPION (typically highly anisotropic particles), which induce a very localized effect with potentially few side effects. Compared to hyperthermia-based methods, the magneto-mechanical treatment mode requires lower frequencies (i.e., ELMF between 2 and 20 Hz compared to kHz frequencies regarding MHT), which could appear relevant from a safety point of view.
Li and collaborators investigated the effects of SPION on tumor cells under extremely low frequency magnetic field exposure conditions (ELMF; 2–20 Hz at intensities varying between 0.1–20 mT) [39]. They found significant morphological changes in tumor cells treated with SPION in combination with ELMF; destructive effects of SPION and ELMF on tumor tissues were further determined by the pathophysiological changes observed in vivo. Maximal effect was observed at the highest frequency (20 Hz) as well as the highest field strength (20 mT). More recently, Lopez et al. found that CCK2-targeting 6 nm-SPION (modified with gastrin peptide) can disrupt the tumor microenvironment through mechanical forces upon low frequency rotating magnetic field exposure [40]. They assumed local mechanical damage of lysosome membranes as a consequence of a torque produced by the SPION inside lysosomes under a rotating magnetic field. Martínez-Banderas et al. promoted cancer cell death by combining the chemotherapeutic effect of DOX-modified iron nanowires with the mechanical disturbance under a low frequency AMF [41]. In their study, they found a synergistic cytotoxic effect arising from the combination of a chemotoxic and magneto–mechanical treatment (1 mT, 10 Hz). Guo found magnetic hybridized microparticles (i.e., Fe3O4/BSA/rSiO2) with a flagellum-like surface as force-mediated cancer treatment [42]. The cell killing efficiency increased with increasing magnetic field frequency (≤3 Hz), vibrating magnetic field (VMF) exposure time (≤1.5 h), and microsphere concentration. In combination with VMF, their system efficiently inhibited mouse tumor growth when compared to microspheres without a VMF.
Magnetic hyperthermia is an extensively studied form of hyperthermia therapy that involves the excitation of a magnetic substance through an AMF-induced movement. Consequent to such exposure, heat can be released in the vicinity of the SPION. In the context of cancer therapy, this modality of treatment implies locally increasing the temperature to a range between 39 and 45 °C inside the tumor zone in order to kill cancerous cells or to sensitize them against other modalities of treatments. The major advantage of such a technique in comparison of other common modalities of treatment for cancer (e.g., surgery, chemotherapy, radiotherapy) is an increased specificity in the localization of the deposited effect. In other words, MH implies that solely the area that has internalized a magnetic substance and that is targeted with an AMF would be exposed to an increase in temperature and consequently to a biological effect (assuming that the Hergt’s biological safety limit is not exceeded which is likely to be true in a clinical setup [43]).
Several anticancer mechanisms of actions have been described for hyperthermia through the years including perturbation of the DNA repair process [44], fluidification of the cellular membranes [45], induction of programmed cell death [46][47][48][49], denaturation of proteins [50], modulation of the expression and activity of certain proteins [51], and modulation of the TME characteristics [51][52]. It must be mentioned that despite numerous investigations about the anticancer potential of SPION as an MH platform, several issues remain critical for their use in the context of cancer treatment by MH. These issues include:
The optimization of the physico-chemical parameters of the SPION platforms (incl. material, magnetic behavior when exposed to a magnetic field, size, shape, and concentration) and the AMF parameters (incl. amplitude and frequency, the time of exposure to the AMF) with regards to the biological effectiveness of MH on cancerous cells [53].
  • The obtention of a high biocompatibility for the nanoplatform when not exposed to an AMF with regards to the biological environment.
  • The preparation of a highly tumor-specific accumulating platform.
With respect to the abovementioned critical issues, an illustrative study can be seen in the work of Kandasamy and colleagues which focused on the heat-generating capability of 9 nm core sized SPION functionalized with different combinations of trimesic acid (TMA), pyromellitic acid (PMA), 2-aminoterephthalic acid (ATA), and terephthalic acid (TA) coatings under various concentrations (from 0.5 to 8 mg/mL) and AMF parameters (from approximately 100 to 1000 kHz). This entry highlighted the complexity of the as-mentioned parameter interactions in a context of optimization of the heating capability of the SPION. As an illustration of this complexity, the specific absorption rate (SAR, which relates to the amount of thermic energy release per quantity of SPION) of TA-ATA bifunctionalized SPION have displayed mixed decrement/increment patterns for various concentrations in considered magnetic fields.
Another strategy for the optimization of a SPION platform regarding their heat-generating ability is the preparation of mixed ferrites having higher magnetization values, thanks to the presence of other ions such as manganese, cobalt, etc., within their oxide core [54][55]. As an example, this strategy was described by Kowalik et al. who took advantage of the doping of Fe3O4 NPs with yttrium trivalent ions [56]. By using this strategy, it was demonstrated that Fe3O4 NPs doped with 0.1% Y3+ ions dramatically decreased the viability of 4T1 cancer cells compared to Fe3O4 without doping. When the cells were subjected to the AMF for 30 min, using concentrations of 35 µg/mL and 100 µg/mL of the Fe3O4:0.1% Y NPs, the authors found a stronger decrease of cell viability for Y-doped NPs in comparison with pure Fe3O4 NPs. Another SPION doping strategy was presented in the paper of Phong et al. [57].
Even if the specificity of the action of SPION-induced MH on cancerous cells is passively ensured by a reduced heat resistance capacity in comparison with healthy cells [49][55], the specificity of the action of MH should be increased to minimize the damage to sensitive healthy areas. One of the strategies available to reach this goal is to properly functionalize the SPION with active targeting elements, such as peptides, nanobodies, or antibodies. Such a strategy was evaluated by Legge [58].
The above-cited studies considered the sole role of MH for the treatment of cancer. However, it should be noted that it has been recently proposed to use MH to induce a cytotoxic effect on cancerous cells and, at the same time, sensitize them to other therapeutic strategies such as chemotherapy. Owing to the ability of SPION to produce heat following exposure to an external alternative magnetic field (AMF), one may expect improved drug release rates following thermal activation. To control the dosage of the cargo released by an AMF actuation, Chen proposed a superparamagnetic doped iron oxide core@shell nanoparticle (MnFe2O4@CoFe2O4) embedded within a mesoporous silica shell [59] and modified with a thermo-responsive molecular gatekeeper containing aliphatic azo group (i.e., thermal-labile 4,4′-azobis(4-cyanovaleric acid moiety) to regulate the cargo release. Efficient stepwise cargo release was achieved by applying multiple sequential AMF. On the same basis, El Boubbou et al. recently developed a PVP-coated SPION platform loaded with doxorubicin [60]. The doxorubicin-loaded and PVP-coated SPION were shown to be much more potent to the cells than the doxorubicin-free PVP-coated SPION platform when this platform was evaluated in vitro on MDA-MB-23 cancer cells under AMF. Even in brief experiment periods (15 min) at relatively modest dosages (0.5 mg·mL−1) and clinically relevant magnetic fields (H0 = 170 Oe and frequency = 332.8 kHz), the loss in cell viability was noticeable.
Another doxorubicin-loaded SPION platform was proposed by Sabouri et al. [61]. This investigation was about the dual osteosarcoma treatment-bone regeneration potential of a SPION platform encapsulated in a biogel. The resultant particles were bioactive as a result of the development of a hydroxyapatite layer on their surface while doxorubicin cargo was used to produce anticancer effects. This platform was tested in vitro on a human osteosarcoma cell line (MG63) which showed that at pH 5.1, doxorubicin-loaded particles released their content in a regulated manner, which was accompanied by a substantial loss in cell viability.

4. ROS-Mediated Therapies

4.1. Macrophage Polarization

Among the many applications of magnetic nanoparticles in cancer therapy, recent studies have found biological effects arising from the intrinsic properties of the iron oxide core being able to induce the generation of reactive oxygen species (ROS) and to modulate intracellular redox mechanisms or iron metabolism [62]. Tumor-associated macrophages (TAMs) are key components of tumor metastasis, playing a significant role as metastasis promoters in the TME [63]. Activation or polarization of TAMs, from tumor-promoting phenotype (M2) to tumor-suppressing phenotype (M1), has been found to be a promising immunotherapeutic treatment in oncology [64][65][66].
As an example, Zanganeh et al. found significant tumor growth inhibition induced by ferumoxytol [67]. This effect was demonstrated to be the result of macrophage polarization into pro-inflammatory M1 phenotypes, along with an enhancement of ROS production leading to increased cancer cell cytotoxicity. A complementary study performed by Zhang et al. found the role of particle charge on the polarizing effect of iron oxide nanoparticles [68]. Both positively charged and negatively charged nanoparticles were able to repolarize macrophages, while neutral nanoparticles did not show significant tumor growth inhibition. The relationship between iron oxide nanoparticle structure and macrophages activation has been investigated by Gu et al., whose work found that higher levels of intracellular iron released from magnetite nanoparticles is the key for superior macrophage polarization and better antitumor performance [69]. Iron oxide nanoparticles with different morphologies have been synthesized for re-polarization therapy, and porous hollow iron oxide nanoparticles were developed by Li et al. and evaluated for TAMs targeting and switching to pro-inflammatory M1-phenotype [70]. Such nanoparticles, combined with 3-methyladenine (3-MA) and modified with mannose for TAMs targeting, were demonstrated to activate the inflammatory factor NF-κB p65 of macrophages responsible for macrophage polarization and subsequent inhibition of tumor growth demonstrated in vivo. Nanoparticles with four different morphologies, namely octapods, cubes, spheres, and plates, were synthesized by Liu et al. and studied regarding inflammasome activation [71]. In their work, they demonstrated that octapods and plates exhibit significantly higher inflammasome-activating capacity compared to cubes and spheres, hence suggesting that particle design must be considered when evaluating new immunotherapeutic formulations based on magnetic nanoparticles.

4.2. Ferroptosis

Besides macrophage polarization, iron oxide nanoparticles can exert a cytotoxic effect through a peculiar type of regulated necrosis called ferroptosis. This form of iron-programmed cell death is triggered by high levels of iron ions and ROS, leading to peroxidation of lipids and eventually cell death [72][73][74]. Wen et al., for example, studied the relationship between autophagy pathway and ultrasmall iron oxide nanoparticles-induced ferroptosis [75]. Results showed that these nanoparticles could significantly upregulate the ferroptosis markers in glioblastoma cells, while suggesting that the induced ferroptosis is regulated via Beclin1/ATG5-dependent autophagy pathways. More recently, different-sized iron oxide nanoparticles were investigated by Tian et al. regarding their antitumor effect and toxicity mechanism. Ultrasmall nanoparticles with diameters below 5 nm were found to be more efficient for the generation of ROS in the nucleus due to quicker release of Fe2+, though 10 nm nanoparticles displayed the best antitumor effect in vivo. Fernandez-Acosta et al. described the synthesis of SPION functionalized with gallic acid (GA) and polyacrylic acid (PAA) [76], previously used as support for the immobilization of Trametes versicolor laccase and subsequent removal of organic dyes [77], and confirmed their intrinsic anticancer activity mediated by ferroptosis execution. Cell death through ferroptosis was confirmed in glioblastoma, neuroblastoma, and fibrosarcoma cells. More recently, Wu et al. [78] found SPION-induced macrophage polarization toward an M1 phenotype and activation of the ferroptosis pathway through the upregulation of P53, a transcription factor responsible for suppressing tumor growth [79].

4.3. Chemodynamic Therapy

Chemodynamic therapy (CDT) has recently emerged as a therapeutic strategy taking advantage of the intrinsic sensibility of cancer cells to oxidative damages and the characteristics of the TME to treat cancers with high specificity [80]. The as-mentioned characteristics of the TME include mild acidity, hypoxia, H2O2 and glutathione (GSH) overexpression, and high nutrient consumption, all of which can modulate the impact of CDT in the context of cancer therapy.
A non-optimized CDT can present a limited therapeutical effect due to the limitations of the TME characteristics. For example, it is well known that H2O2 is overexpressed in cancer cells (over 100 µM) due to their abnormal growth and metabolism [81]. However, this increased concentration of substrates is still too low for an optimal Fenton’s reaction considering the overexpression of GSH in cancer cells. To overcome this limitation, Huo and coworkers created a subsequent nanoreactor by co-encapsulating glucose oxidase (GOx) and SPION into biodegradable dendritic silica nanoparticles [82].
O2 + H2O + glucose → gluconic acid+ H2O2
A similar nanocatalyst was developed by the research group of Feng et al. which proposed a therapeutic approach based on composite nanocatalysts made of SPION encapsulating polypyrrole (PPy) and Gox (Fe3O4@PPy@Gox) [83]. This approach successfully produced chemodynamically triggered cancer hyperthermia, dual-modality diagnostic imaging-guided and nanocatalytic therapy based on the chemo-Fenton catalytic reaction (as mentioned above). Similarly, Dong and colleagues created a magnetic targeting nanoplatform by encapsulating ultrasmall γ-Fe2O3 nanoparticles and GOx to dendritic mesoporous silica (DMSN) spheres (γ-Fe2O3-GOx-DMSN) [84].
Another CDT limiting factor relies on the ability of GSH to quench oxidative molecules. To circumvent this limitation, Zhao et al. proposed a ROS-activatable liposome loaded with hexadecyl-oxaliplatin carboxylic acid (HOC) and Fe3O4 nanoparticles (RALP@HOC@Fe3O4) [85]. In this model, HOC acts as a prodrug that would be metabolized by GSH into oxaliplatin (OXA) while inducing the starvation of GSH in the cancerous cells. This breakdown of the tumor cells weakening the redox equilibrium induces an increased generation of H2O2 while the released SPION provide a substrate for the Fenton’s reaction. This model has been tested on a CT26 xenograft murine model and showed a significant reduction in tumor growth speed. A similar strategy was proposed by Chen et al. This platform (Fe3O4-HSA@Lapa NP) overexpressed NQO1 enzyme and catalyzed the amount of released Lapa, which resulted in a large amount of O2•, which was then converted into H2O2 by superoxide dismutase (SOD). Conversely, in the acidic endolysosome environment, ferrous ions from Fe3O4 combined with overproduced H2O2 catalyze the formation of OH• by the Fenton reaction, which finally led to cell death. Additionally, the use of NADPH in the futile Lapa cycle led to GSH depletion, altering the antioxidant defense system and increasing the sensitivity of cancer cells to OH• produced in the Fenton chemical reaction, hence intensifying the anticancer impact both in A549 cells and the xenografted in vivo mouse model A459.
The Fenton reaction appears to be pH-dependent (optimal pH around 3) [86]; the higher pH value of TME (pH 5–7) is thus not suitable for this catalytic conversion. To counteract this barrier, Shi et al. created an acid-unlocked nanoplatform loaded with the pH-sensitive drug tamoxifen (TAM) (FePt@FeOx@TAM-PEG) [87]. The above work showed the release of TAM drug for the inhibition of mitochondrial complex I, which after several cascade events causes the increase in intracellular H+. Due to the decrease of pH, FePt@FeOx nanocatalyst may also be released, which would cause a Fenton-like reaction. An increase in DNA damage has been observed in cancer cells treated with FePt@FeOx@TAM-PEG. In addition, in vivo treatment on 4T1 xenografted mice has been successfully carried out using the increased ROS production. Another strategy involving the modulation of the TME’s pH has been described by Liu et al.
The high metabolic activity of cancer cells in conjunction with the limited vascularization of this area can, in some cases, induce hypoxia, thus altering the presence of ROS and consequently decreasing the CDT impact. Recently, Li et al. described a SPION platform enriched with manganese ions and pyropheophorbide (PPA) [88] and providing high glutathione-peroxidase-like, Fenton-like, and catalase-like activity. The rationality between this combination of functions is that catalase-like activity induces a catalyzed conversion of H2O2 to O2 and subsequently decreases the hypoxic state of TME. In addition, the glutathione-peroxidase-like activity was involved in the reduction of GSH concentration in the TME and subsequently the resistance of cancer cells to oxidative damage. Finally, Fenton-like activity gives the platform the ability to catalyze H2O2 conversion in OH• and exert a CDT activity.
Additional studies focused on the relevance of electric-assisted Fenton reactions. As an example, Chen’s team described SPION decorated with platinum nanocrystals (Fe3O4@Pt NP), which combine CDT with electrodynamic therapy (EDT) [89]. This platform showed an ability to produce ROS due to an electric-field-induced catalysis on the surface of platinum. In the meantime, Fe2+/Fe3+ from Fe3O4@Pt NP may stimulate the Fenton reaction to turn intracellular H2O2 into ROS and consume GSH (inhibiting ROS clearance). As a result, a significant tumor inhibition capability was seen both in vitro and in vivo when exposed to an electric field. Another strategy involving the extra-production of ROS by platinum has been described by Ma et al., who presented multifunctional Janus nanoparticles (Fe3O4-Pd JNPs) that combine ultrasmall Fe3O4 and Pd nanosheets for the treatment of breast cancer [90].

4.4. Light-Mediated Therapy

Besides taking direct advantage of the TME to trigger Fenton reaction and iron-catalyzed reactions leading to the formation of ROS, combining SPION with photosensitizers capable of inducing the release of ROS or heat upon exposure to UV-visible or near infra-red (NIR) light is a growing research topic in the field of cancer therapy. Illumination of a photosensitizer using UV light can trigger photochemical reactions with oxygen leading to the production of ROS, responsible for cancer cell death. Promoting ROS production using this mechanism is generally referred to as photodynamic therapy (PDT). Alternatively, photosensitizers can release heat when irradiated with NIR light and cause the destruction of cancer cells through several mechanisms. This strategy is known as photothermal therapy (PTT).
The principle of PDT is the formation of ROS by irradiation of photosensitizers with a specific wavelength of light energy, usually a laser. By absorbing a photon, the photosensitizer reaches an excited singlet state that rapidly transits to a triplet state through an inter-crossing system. The triplet state has a longer half-life, allowing interaction with ground state dioxygen or other cellular compounds [91][92]. There are two types of photodynamic processes, the first, called type I, is the transfer of an electron from the triplet state photosensitizer to a cellular compound such as a protein, lipid, or nucleotide resulting in the formation of ROS species. The second type, type II, is the energy transfer from the triplet state to a dioxygen molecule in the ground state, leading to the formation of cytotoxic singlet oxygen [93].
In the best-case scenario, a photosensitizer would generate singlet oxygen when exposed to a specific wavelength, while being harmless under normal conditions, and would be able to precisely target cancer cells due to certain characteristics. So far, three generations of PS have been developed. The first generation consists of a natural mixture of hematoporphyrin derivatives. The second generation is pure synthetic compounds that absorb light in the vis-NIR. The third generation refers to photosensitizers with additional features that enhance their biomedical uses such as antibodies or nanotechnology [94].
PDT is a minimally invasive technique which, as for other techniques implying light emission, is limited by light penetration through tissues. Employing photosensitizers absorbing within the therapeutic window (i.e., range of wavelengths where light has maximum penetration in tissues [95]) is mandatory. Common photosensitizers are excited using wavelengths between 650 and 800 nm, which stands within the window. However, PDT remains limited to treating skin cancers or tumors located on a mucous membrane accessible to an endoscope [96]. A way around this restriction is the use of optical fibers to reach most of the body cavities, even for vertebral metastasis as described by Fisher et al. by combining PDT with vertebral cement augmentation [97]. Besides optical properties, PDT outcome is dependent on the nature of the photosensitizers, which are generally known for their hydrophobicity, resulting in poor circulation half-life and restrained therapeutic efficacy. Furthermore, photosensitizing molecules lack specificity for targeting tumor cells. This could lead to mid- and long-term adverse effects, such as whole-body photosensitivity. The use of SPION as nanocarriers is a way to overcome the targeting and hydrophobicity issues [91]. SPION are mainly used as nanocarriers due to their ability to penetrate and accumulate into cancer cells by EPR effect. Specific targeting is also possible with adapted coating, such as transferrin, antibodies, aptamers, hyaluronic acid, folate, and targeting peptides [98]. As an example, Li et al. described the use of SPION synthesized by thermal decomposition in polyol solvents as nanocarriers for doxorubicin and chlorin e6 (Ce6). Researchers found an enhanced cell uptake due to the formation of clusters loaded with Ce6 through physical adsorption and coordination with surface atoms. In vivo PDT efficacy was evaluated in mouse subcutaneous melanoma grafts, and enhanced PDT efficacy was demonstrated to be the result of Dox specific release in cancer cells due to the acid-sensitive hydrazone linkage between the drug and the nanocarrier [99].
PTT is a selective and minimally invasive therapeutic strategy used for cancer cell thermal ablation. Thermal ablation consists of a local increase in temperature above 42 °C, for short time periods. Depending on the temperature threshold, cancerous cells can be killed over long periods of time (at 42 °C) or within shorter time windows (i.e., 4–6 min) when increasing the temperature over 50 °C [100].
Heat production comes from the irradiation of photothermal agents, which dissipate the received energy in the form of heat by various processes. As an example, metallic nanoparticle-induced heat generation comes from synchronized oscillations of the conduction band electrons generated by the irradiation (LSPR). There is a large panel of photothermal agents (PAs) of different nature, and their ability to increase temperature depends on their photothermal conversion efficiency. Similar to PDT, the excitation of PAs is performed using specific wavelengths within the therapeutic window. Although PAs are commonly excited using longer wavelengths (compared to PDT), either in the NIR light range (from 650 to 1024 nm), although most use irradiation wavelengths of 808 nm and 980 nm. The advantages of PTT are its low invasiveness, spatial accuracy, and the fact that it does not require the presence of intracellular O2 unlike PDT. Despite this, this technique suffers from some constraints, the most obvious being the shallow penetration depth of the NIR light into the tissue. Even though there are NIR-I (750–1000 nm) and NIR-II (1000–1700 nm) windows, the penetration depth remains in the order of the cm [100][101][102].
SPION can be used in two ways in PTT. Similar to PDT, they can serve as nanocarriers for other PAs by providing stability and a way to enter and accumulate in cancer cells via the EPR effect. Unlike in PDT, SPION can directly serve as therapeutic agents, as they generate heat under NIR irradiation [103]. The applicability of PEG-starch-SPION for PTT was studied by Amatya et al. for the treatment of glioblastoma [104]. Laser irradiation of the tumor site using a 885 nm wavelength 4 h after the administration of SPION led to a significant temperature increase (above 45 °C) which was sufficient for effective inhibition of tumor growth. Dheyab et al. developed gold-coated SPION, generating heat via localized plasmon resonance, and evaluated cell viability following photothermal therapy treatment [105]. MCF-7 cells treated with Au-SPION, and irradiated with NIR light (808 nm, 200 mW, 10 min) displayed a significant decrease in viability due to the PTT treatment, demonstrating that such systems are promising for image-guided PTT treatment of breast cancer. Combining PTT with PDT is also possible through the coating of SPION with photosensitizers generating ROS under irradiation. Zhang et al. showed the use of green and biocompatible components to develop glucose oxidase (GOx) and polydopamine (PDA) coated SPION. GOx is a photosensitizer which is able to generate high levels of H2O2 that can react with SPION to form OH● radicals via a Fenton-like reaction. A PTT-ROS dual-modality system was hence constructed, in which PDA was used as both cross-linking platform and PA, and SPION were used as carriers and catalyzers for the generation of radicals. In vivo study on 4T1 tumor-bearing Balb/c mice was performed and confirmed the efficient combination between ROS generation and PTT, characterized by selective anticancer effect and significant tumor suppression. Another way of improving the selectivity of PA-bearing SPION towards the tumor site is the use of magnetically guided targeting approach. This strategy was employed by Wang et al.who engineered SPION coated with silicone dioxide and indocyanine green (ICG) as PAs. Particle accumulation in cancer cells was enhanced through the combination of magnetic guiding and the natural ability of neutrophils to infiltrate tumor tissues [106]. Due to these combined strategies, the authors found stronger contrast enhancement in the tumor region, as well as a marked enhancement of the curative effect after the photothermal process.

4.5. Combination with Radiation Therapy

Nowadays, radiation therapy, more commonly called radiotherapy (RT) appears as a major strategy against cancer [107][108][109]. The importance of RT in the therapeutic handling of cancer is such that it is estimated that more than 50% of the patients treated for cancer will require at least one dose of RT during their treatments [110][111]. The mechanism of action of radiotherapy is based on irradiation and consequently the induction of direct or indirect damage induction to many cellular structures such as DNA [112], proteins [113], lipids [114][115], or the water constituting the cytoplasm [116][117].
Recently, numerous advances (e.g., FLASH RT, proton therapy, fractionation of the treatment, intensity modulated RT) have been achieved in the field of RT to increase accuracy, specificity, and efficacy in radiation treatment [118][119][120][121][122]. However, the main limitation of RT is still the potential lack of precision during the irradiation of the tumors, the radio-resistance developed in some cases by the tumors, and the radiosensitivity surrounding normal tissues. Thus, the use of radiosensitizers (e.g., molecules or particles) appears as a promising approach to enhance RT efficiency, thus reducing the normal tissue damage while keeping the same biological effect against the cancerous cells.
Owing to a higher attenuation coefficient, the radiosensitization strategies have mainly focused on high atomic number nanoparticles (High Z NPs) [123][124][125][126][127][128][129][130][131]. However, some emerging studies used nanomaterials that have the ability to improve RT efficiency through other mechanisms such as SPION. One of the main mechanistic descriptions of the radiosensitization process related to SPION appears to be the Fenton’s and Haber–Weiss’ reactions. Under physiological conditions, most of the intracellular iron appears to be bound to iron binding proteins such as ferritin, resulting in only trace amounts of free intracellular iron. However, under the presence of SPION, several works mention that the internalization of iron oxide nanoparticles can lead to an increase in the concentration of free intracellular iron which may be involved in the production of excessive ROS that could further alter the cellular homeostasis [132]. This extra production of ROS could finally lead to irreversible cellular injury or to cell apoptosis, especially when SPION are combined with additional treatment such as RT [133][134]. In addition to Fenton’s and Haber–Weiss’ reactions related considerations, several mechanisms have been proposed to explain the radiosensitizing potential of SPION through the last years.
Shetake et al. reported that oleic acid modified SPION could interact with HSP60 and HSP90 which are key proteins in the mitotic process as well as in the DNA repair process [135]. This observation suggests SPION related radiosensitization mechanism involving the direct interaction between a SPION and a protein. He et al. suggested that SPION can interfere with the electron transport chain within mitochondria (METC) of cancerous cells, which also affects ATP synthesis, the mitochondrial membrane potential, calcium microdistribution, and favor the induction cell death process. In addition, due to the reduced antioxidative ability of cancer cells, SPION are also suggested to cause the generation of reactive oxygen species in mitochondria which are all elements that can amplify the effect of RT [136].
Most of the reports that have been currently presented focused on the use of SPION with an external radiation beam. However, Stanković et al. synthesized and evaluated 131I-labeling APTES functionalized SPION and took advantage of the radionuclide radiopharmaceuticals for nanoparticle mediated brachytherapy. This report investigated the potential of this particular platform with regard to the brachytherapy aspect but also showed that this effect could be enhanced when applied in combination with magnetic induced hyperthermia. Nevertheless, they demonstrated the use of 131I-APTES functionalized SPION without magnetic-induced hyperthermia was sufficient to induce a significant lowering of the tumor growth rate [137]. Similarly, Zuk et al. explored the potential of SPION containing a radioactive isotope of gold and functionalized with trastuzumab in order to target HER-2 positive cancer cells [138]. This strategy allowed the authors to induce a significant regression of spheroid growth. The synergy between MH and RT was also demonstrated by the group of Lin that synthesized and evaluated a magnetic silica encapsulated multi-core SPION platform coated with folic acid and L-selenocystine [139]. This platform, tested on Hela cells, human breast cancer cells (MDA-MB-231), and human umbilical vein endothelial cells (HUVEC) showed a high saturation magnetization and an ability to produce increased ROS amount when exposed to X-rays beams. Taken together, these features showed a synergistic effect on the elimination of cancer cells and highlighted the therapeutic interest to combine MH and RT.

This entry is adapted from the peer-reviewed paper 10.3390/pharmaceutics15010236

References

  1. Gupta, P.; Lakes, A.; Dziubla, T. Chapter One—A Free Radical Primer. In Oxidative Stress and Biomaterials; Dziubla, T., Butterfield, D.A., Eds.; Academic Press: Cambridge, MA, USA, 2016; pp. 1–33. ISBN 978-0-12-803269-5.
  2. Pérez-Herrero, E.; Fernández-Medarde, A. Advanced targeted therapies in cancer: Drug nanocarriers, the future of chemotherapy. Eur. J. Pharm. Biopharm. 2015, 93, 52–79.
  3. Tewabe, A.; Abate, A.; Tamrie, M.; Seyfu, A.; Abdela Siraj, E. Targeted Drug Delivery—From Magic Bullet to Nanomedicine: Principles, Challenges, and Future Perspectives. J. Multidiscip. Healthc. 2021, 14, 1711–1724.
  4. Schleich, N.; Sibret, P.; Danhier, P.; Ucakar, B.; Laurent, S.; Muller, R.N.; Jérôme, C.; Gallez, B.; Préat, V.; Danhier, F. Dual anticancer drug/superparamagnetic iron oxide-loaded PLGA-based nanoparticles for cancer therapy and magnetic resonance imaging. Int. J. Pharm. 2013, 447, 94–101.
  5. Quan, Q.; Xie, J.; Gao, H.; Yang, M.; Zhang, F.; Liu, G.; Lin, X.; Wang, A.; Eden, H.S.; Lee, S.; et al. HSA Coated Iron Oxide Nanoparticles as Drug Delivery Vehicles for Cancer Therapy. Mol. Pharm. 2011, 8, 1669–1676.
  6. Zhao, S.; Yu, X.; Qian, Y.; Chen, W.; Shen, J. Multifunctional magnetic iron oxide nanoparticles: An advanced platform for cancer theranostics. Theranostics 2020, 10, 6278–6309.
  7. Yue, L.; Sun, C.; Kwong, C.H.T.; Wang, R. Cucurbituril-functionalized Magnetic Nanoparticles for Imaging-guided Cancer Therapy. J. Mater. Chem. B 2020, 8, 2749–2753.
  8. Tay, Z.W.; Chandrasekharan, P.; Zhou, X.Y.; Yu, E.; Zheng, B.; Conolly, S. In vivo tracking and quantification of inhaled aerosol using magnetic particle imaging towards inhaled therapeutic monitoring. Theranostics 2018, 8, 3676–3687.
  9. Tomitaka, A.; Arami, H.; Huang, Z.; Raymond, A.; Rodriguez, E.; Cai, Y.; Febo, M.; Takemura, Y.; Nair, M. Hybrid magneto-plasmonic liposomes for multimodal image-guided and brain-targeted HIV treatment. Nanoscale 2018, 10, 184–194.
  10. Bulte, J.W.M. Superparamagnetic iron oxides as MPI tracers: A primer and review of early applications. Adv. Drug Deliv. Rev. 2019, 138, 293–301.
  11. Stueber, D.D.; Villanova, J.; Aponte, I.; Xiao, Z.; Colvin, V.L. Magnetic Nanoparticles in Biology and Medicine: Past, Present, and Future Trends. Pharmaceutics 2021, 13, 943.
  12. Jung, K.O.; Jo, H.; Yu, J.H.; Gambhir, S.S.; Pratx, G. Development and MPI tracking of novel hypoxia-targeted theranostic exosomes. Biomaterials 2018, 177, 139–148.
  13. Liang, X.; Wang, K.; Du, J.; Tian, J.; Zhang, H. The first visualization of chemotherapy-induced tumor apoptosis via magnetic particle imaging in a mouse model. Phys. Med. Biol. 2020, 65, 195004.
  14. Zhu, X.; Li, J.; Peng, P.; Hosseini Nassab, N.; Smith, B.R. Quantitative Drug Release Monitoring in Tumors of Living Subjects by Magnetic Particle Imaging Nanocomposite. Nano Lett. 2019, 19, 6725–6733.
  15. Wu, J. The Enhanced Permeability and Retention (EPR) Effect: The Significance of the Concept and Methods to Enhance Its Application. J. Pers. Med. 2021, 11, 771.
  16. Fang, J.; Islam, W.; Maeda, H. Exploiting the dynamics of the EPR effect and strategies to improve the therapeutic effects of nanomedicines by using EPR effect enhancers. Adv. Drug Deliv. Rev. 2020, 157, 142–160.
  17. Cheng, Z.; Li, M.; Dey, R.; Chen, Y. Nanomaterials for cancer therapy: Current progress and perspectives. J. Hematol. Oncol. 2021, 14, 85.
  18. Narum, S.M.; Le, T.; Le, D.P.; Lee, J.C.; Donahue, N.D.; Yang, W.; Wilhelm, S. Passive targeting in nanomedicine: Fundamental concepts, body interactions, and clinical potential. In Nanoparticles for Biomedical Applications; Elsevier: Amsterdam, The Netherlands, 2020; pp. 37–53.
  19. Frtús, A.; Smolková, B.; Uzhytchak, M.; Lunova, M.; Jirsa, M.; Kubinová, Š.; Dejneka, A.; Lunov, O. Analyzing the mechanisms of iron oxide nanoparticles interactions with cells: A road from failure to success in clinical applications. J. Control. Release 2020, 328, 59–77.
  20. Nosrati, R.; Abnous, K.; Alibolandi, M.; Mosafer, J.; Dehghani, S.; Taghdisi, S.M.; Ramezani, M. Targeted SPION siderophore conjugate loaded with doxorubicin as a theranostic agent for imaging and treatment of colon carcinoma. Sci. Rep. 2021, 11, 13065.
  21. Jia, G.; Han, Y.; An, Y.; Ding, Y.; He, C.; Wang, X.; Tang, Q. NRP-1 targeted and cargo-loaded exosomes facilitate simultaneous imaging and therapy of glioma in vitro and in vivo. Biomaterials 2018, 178, 302–316.
  22. Qi, H.; Liu, C.; Long, L.; Ren, Y.; Zhang, S.; Chang, X.; Qian, X.; Jia, H.; Zhao, J.; Sun, J.; et al. Blood Exosomes Endowed with Magnetic and Targeting Properties for Cancer Therapy. ACS Nano 2016, 10, 3323–3333.
  23. De Lavera, I.; Merkling, P.J.; Oliva, J.M.; Sayagués, M.J.; Cotán, D.; Sánchez-Alcázar, J.A.; Infante, J.J.; Zaderenko, A.P. EGFR-targeting antitumor therapy: Neuregulins or antibodies? Eur. J. Pharm. Sci. 2021, 158, 105678.
  24. Zhu, J.-Y.; Zheng, D.-W.; Zhang, M.-K.; Yu, W.-Y.; Qiu, W.-X.; Hu, J.-J.; Feng, J.; Zhang, X.-Z. Preferential Cancer Cell Self-Recognition and Tumor Self-Targeting by Coating Nanoparticles with Homotypic Cancer Cell Membranes. Nano Lett. 2016, 16, 5895–5901.
  25. Meng, X.; Wang, J.; Zhou, J.; Tian, Q.; Qie, B.; Zhou, G.; Duan, W.; Zhu, Y. Tumor cell membrane-based peptide delivery system targeting the tumor microenvironment for cancer immunotherapy and diagnosis. Acta Biomater. 2021, 127, 266–275.
  26. Zhu, K.; Deng, Z.; Liu, G.; Hu, J.; Liu, S. Photoregulated Cross-Linking of Superparamagnetic Iron Oxide Nanoparticle (SPION) Loaded Hybrid Nanovectors with Synergistic Drug Release and Magnetic Resonance (MR) Imaging Enhancement. Macromolecules 2017, 50, 1113–1125.
  27. Zhao, W.; Odelius, K.; Edlund, U.; Zhao, C.; Albertsson, A.-C. In Situ Synthesis of Magnetic Field-Responsive Hemicellulose Hydrogels for Drug Delivery. Biomacromolecules 2015, 16, 2522–2528.
  28. Nowak, B.P.; Niehues, M.; Ravoo, B.J. Magneto-responsive hydrogels by self-assembly of low molecular weight peptides and crosslinking with iron oxide nanoparticles. Soft Matter 2021, 17, 2857–2864.
  29. Ayyanaar, S.; Balachandran, C.; Bhaskar, R.C.; Kesavan, M.P.; Aoki, S.; Raja, R.P.; Rajesh, J.; Webster, T.J.; Rajagopal, G. ROS-Responsive Chitosan Coated Magnetic Iron Oxide Nanoparticles as Potential Vehicles for Targeted Drug Delivery in Cancer Therapy. Int. J. Nanomed. 2020, 15, 3333–3346.
  30. Liu, J.; Liu, W.; Zhang, K.; Shi, J.; Zhang, Z. A Magnetic Drug Delivery System with “OFF–ON” State via Specific Molecular Recognition and Conformational Changes for Precise Tumor Therapy. Adv. Healthc. Mater. 2020, 9, 1901316.
  31. Cai, M.; Li, B.; Lin, L.; Huang, J.; An, Y.; Huang, W.; Zhou, Z.; Wang, Y.; Shuai, W.; Zhu, K. A reduction and pH dual-sensitive nanodrug for targeted theranostics in hepatocellular carcinoma. Biomater. Sci. 2020, 8, 3485–3499.
  32. Ding, X.; Jiang, W.; Dong, L.; Hong, C.; Luo, Z.; Hu, Y.; Cai, K. Redox-responsive magnetic nanovectors self-assembled from amphiphilic polymer and iron oxide nanoparticles for a remotely targeted delivery of paclitaxel. J. Mater. Chem. B 2021, 9, 6037–6043.
  33. Turiel-Fernández, D.; Gutiérrez-Romero, L.; Corte-Rodriguez, M.; Bettmer, J.; Montes-Bayón, M. Ultrasmall iron oxide nanoparticles cisplatin (IV) prodrug nanoconjugate: ICP-MS based strategies to evaluate the formation and drug delivery capabilities in single cells. Anal. Chim. Acta 2021, 1159, 338356.
  34. Hannecart, A.; Stanicki, D.; Vander Elst, L.; Muller, R.N.; Lecommandoux, S.; Thévenot, J.; Bonduelle, C.; Trotier, A.; Massot, P.; Miraux, S.; et al. Nano-thermometers with thermo-sensitive polymer grafted USPIOs behaving as positive contrast agents in low-field MRI. Nanoscale 2015, 7, 3754–3767.
  35. Sharif, S.; Nguyen, K.T.; Bang, D.; Park, J.-O.; Choi, E. Optimization of Field-Free Point Position, Gradient Field and Ferromagnetic Polymer Ratio for Enhanced Navigation of Magnetically Controlled Polymer-Based Microrobots in Blood Vessel. Micromachines 2021, 12, 424.
  36. Wu, Z.; Li, T.; Li, J.; Gao, W.; Xu, T.; Christianson, C.; Gao, W.; Galarnyk, M.; He, Q.; Zhang, L.; et al. Turning Erythrocytes into Functional Micromotors. ACS Nano 2014, 8, 12041–12048.
  37. Liang, Y.; Xie, J.; Yu, J.; Zheng, Z.; Liu, F.; Yang, A. Recent advances of high performance magnetic iron oxide nanoparticles: Controlled synthesis, properties tuning and cancer theranostics. Nano Sel. 2021, 2, 216–250.
  38. Kim, D.; Lee, H.; Kwon, S.; Sung, Y.J.; Song, W.K.; Park, S. Bilayer Hydrogel Sheet-Type Intraocular Microrobot for Drug Delivery and Magnetic Nanoparticles Retrieval. Adv. Healthc. Mater. 2020, 9, 2000118.
  39. Li, W.; Liu, Y.; Qian, Z.; Yang, Y. Evaluation of Tumor Treatment of Magnetic Nanoparticles Driven by Extremely Low Frequency Magnetic Field. Sci. Rep. 2017, 7, 46287.
  40. Lopez, S.; Hallali, N.; Lalatonne, Y.; Hillion, A.; Antunes, J.C.; Serhan, N.; Clerc, P.; Fourmy, D.; Motte, L.; Carrey, J.; et al. Magneto-mechanical destruction of cancer-associated fibroblasts using ultra-small iron oxide nanoparticles and low frequency rotating magnetic fields. Nanoscale Adv. 2022, 4, 421–436.
  41. Martínez-Banderas, A.I.; Aires, A.; Teran, F.J.; Perez, J.E.; Cadenas, J.F.; Alsharif, N.; Ravasi, T.; Cortajarena, A.L.; Kosel, J. Functionalized magnetic nanowires for chemical and magneto-mechanical induction of cancer cell death. Sci. Rep. 2016, 6, 35786.
  42. Guo, Y.; Yang, W.; Pu, G.; Zhu, C.; Zhu, Y.; Li, J.; Huang, Y.; Wang, B.; Chu, M. Low frequency vibrating magnetic field-triggered magnetic microspheres with a nanoflagellum-like surface for cancer therapy. J. Nanobiotechnol. 2022, 20, 316.
  43. Hergt, R.; Dutz, S. Magnetic particle hyperthermia—Biophysical limitations of a visionary tumour therapy. J. Magn. Magn. Mater. 2007, 311, 187–192.
  44. Cellai, F.; Munnia, A.; Viti, J.; Doumett, S.; Ravagli, C.; Ceni, E.; Mello, T.; Polvani, S.; Giese, R.W.; Baldi, G.; et al. Magnetic Hyperthermia and Oxidative Damage to DNA of Human Hepatocarcinoma Cells. Int. J. Mol. Sci. 2017, 18, 939.
  45. Alvarez-Berríos, M.P.; Castillo, A.; Mendéz, J.; Soto, O.; Rinaldi, C.; Torres-Lugo, M. Hyperthermic potentiation of cisplatin by magnetic nanoparticle heaters is correlated with an increase in cell membrane fluidity. Int. J. Nanomed. 2013, 8, 1003–1013.
  46. Wong, D.W.; Gan, W.L.; Teo, Y.K.; Lew, W.S. Interplay of cell death signaling pathways mediated by alternating magnetic field gradient. Cell Death Discov. 2018, 4, 49.
  47. Beola, L.; Asín, L.; Roma-Rodrigues, C.; Fernández-Afonso, Y.; Fratila, R.M.; Serantes, D.; Ruta, S.; Chantrell, R.W.; Fernandes, A.R.; Baptista, P.V.; et al. The Intracellular Number of Magnetic Nanoparticles Modulates the Apoptotic Death Pathway after Magnetic Hyperthermia Treatment. ACS Appl. Mater. Interfaces 2020, 12, 43474–43487.
  48. Clerc, P.; Jeanjean, P.; Hallali, N.; Gougeon, M.; Pipy, B.; Carrey, J.; Fourmy, D.; Gigoux, V. Targeted Magnetic Intra-Lysosomal Hyperthermia produces lysosomal reactive oxygen species and causes Caspase-1 dependent cell death. J. Control. Release 2018, 270, 120–134.
  49. Salimi, M.; Sarkar, S.; Hashemi, M.; Saber, R. Treatment of Breast Cancer-Bearing BALB/c Mice with Magnetic Hyperthermia using Dendrimer Functionalized Iron-Oxide Nanoparticles. Nanomaterials 2020, 10, 2310.
  50. Boitard, C.; Michel, A.; Ménager, C.; Griffete, N. Protein Denaturation Through the Use of Magnetic Molecularly Imprinted Polymer Nanoparticles. Molecules 2021, 26, 3980.
  51. Pan, J.; Xu, Y.; Wu, Q.; Hu, P.; Shi, J. Mild Magnetic Hyperthermia-Activated Innate Immunity for Liver Cancer Therapy. J. Am. Chem. Soc. 2021, 143, 8116–8128.
  52. Carter, T.J.; Agliardi, G.; Lin, F.-Y.; Ellis, M.; Jones, C.; Robson, M.; Richard-Londt, A.; Southern, P.; Lythgoe, M.; Zaw Thin, M.; et al. Potential of Magnetic Hyperthermia to Stimulate Localized Immune Activation. Small 2021, 17, e2005241.
  53. Kandasamy, G.; Sudame, A.; Bhati, P.; Chakrabarty, A.; Maity, D. Systematic investigations on heating effects of carboxyl-amine functionalized superparamagnetic iron oxide nanoparticles (SPIONs) based ferrofluids for in vitro cancer hyperthermia therapy. J. Mol. Liq. 2018, 256, 224–237.
  54. Hedayatnasab, Z.; Abnisa, F.; Daud, W.M.A.W. Review on magnetic nanoparticles for magnetic nanofluid hyperthermia application. Mater. Des. 2017, 123, 174–196.
  55. Pucci, C.; Degl’Innocenti, A.; Gümüş, M.B.; Ciofani, G. Superparamagnetic iron oxide nanoparticles for magnetic hyperthermia: Recent advancements, molecular effects, and future directions in the omics era. Biomater. Sci. 2022, 10, 2103–2121.
  56. Kowalik, P.; Mikulski, J.; Borodziuk, A.; Duda, M.; Kamińska, I.; Zajdel, K.; Rybusinski, J.; Szczytko, J.; Wojciechowski, T.; Sobczak, K.; et al. Yttrium-Doped Iron Oxide Nanoparticles for Magnetic Hyperthermia Applications. J. Phys. Chem. C 2020, 124, 6871–6883.
  57. Phong, L.T.H.; Manh, D.H.; Nam, P.H.; Lam, V.D.; Khuyen, B.X.; Tung, B.S.; Bach, T.N.; Tung, D.K.; Phuc, N.X.; Hung, T.V.; et al. Structural, magnetic and hyperthermia properties and their correlation in cobalt-doped magnetite nanoparticles. RSC Adv. 2022, 12, 698–707.
  58. Legge, C.J.; Colley, H.E.; Lawson, M.A.; Rawlings, A.E. Targeted magnetic nanoparticle hyperthermia for the treatment of oral cancer. J. Oral Pathol. Med. 2019, 48, 803–809.
  59. Chen, W.; Cheng, C.-A.; Zink, J.I. Spatial, Temporal, and Dose Control of Drug Delivery using Noninvasive Magnetic Stimulation. ACS Nano 2019, 13, 1292–1308.
  60. El-Boubbou, K.; Lemine, O.M.; Ali, R.; Huwaizi, S.M.; Al-Humaid, S.; AlKushi, A. Evaluating magnetic and thermal effects of various Polymerylated magnetic iron oxide nanoparticles for combined chemo-hyperthermia. New J. Chem. 2022, 46, 5489–5504.
  61. Sabouri, Z.; Labbaf, S.; Karimzadeh, F.; Baharlou-Houreh, A.; McFarlane, T.V.; Esfahani, M.H.N. Fe3O4/bioactive glass nanostructure: A promising therapeutic platform for osteosarcoma treatment. Biomed. Mater. 2021, 16, 035016.
  62. Mulens-Arias, V.; Rojas, J.M.; Barber, D.F. The Use of Iron Oxide Nanoparticles to Reprogram Macrophage Responses and the Immunological Tumor Microenvironment. Front. Immunol. 2021, 12, 693709.
  63. Lin, Y.; Xu, J.; Lan, H. Tumor-associated macrophages in tumor metastasis: Biological roles and clinical therapeutic applications. J. Hematol. Oncol. 2019, 12, 76.
  64. Nascimento, C.S.; Alves, É.A.R.; de Melo, C.P.; Corrêa-Oliveira, R.; Calzavara-Silva, C.E. Immunotherapy for cancer: Effects of iron oxide nanoparticles on polarization of tumor-associated macrophages. Nanomedicine 2021, 16, 2633–2650.
  65. Canese, R.; Vurro, F.; Marzola, P. Iron Oxide Nanoparticles as Theranostic Agents in Cancer Immunotherapy. Nanomaterials 2021, 11, 1950.
  66. Reichel, D.; Tripathi, M.; Perez, J.M. Biological Effects of Nanoparticles on Macrophage Polarization in the Tumor Microenvironment. Nanotheranostics 2019, 3, 66–88.
  67. Zanganeh, S.; Hutter, G.; Spitler, R.; Lenkov, O.; Mahmoudi, M.; Shaw, A.; Pajarinen, J.S.; Nejadnik, H.; Goodman, S.; Moseley, M.; et al. Iron oxide nanoparticles inhibit tumour growth by inducing pro-inflammatory macrophage polarization in tumour tissues. Nat. Nanotechnol. 2016, 11, 986–994.
  68. Zhang, W.; Cao, S.; Liang, S.; Tan, C.H.; Luo, B.; Xu, X.; Saw, P.E. Differently Charged Super-Paramagnetic Iron Oxide Nanoparticles Preferentially Induced M1-Like Phenotype of Macrophages. Front. Bioeng. Biotechnol. 2020, 8, 537.
  69. Gu, Z.; Liu, T.; Tang, J.; Yang, Y.; Song, H.; Tuong, Z.K.; Fu, J.; Yu, C. Mechanism of Iron Oxide-Induced Macrophage Activation: The Impact of Composition and the Underlying Signaling Pathway. J. Am. Chem. Soc. 2019, 141, 6122–6126.
  70. Li, K.; Lu, L.; Xue, C.; Liu, J.; He, Y.; Zhou, J.; Xia, Z.; Dai, L.; Luo, Z.; Mao, Y.; et al. Polarization of tumor-associated macrophage phenotype via porous hollow iron nanoparticles for tumor immunotherapy in vivo. Nanoscale 2020, 12, 130–144.
  71. Liu, L.; Sha, R.; Yang, L.; Zhao, X.; Zhu, Y.; Gao, J.; Zhang, Y.; Wen, L.-P. Impact of Morphology on Iron Oxide Nanoparticles-Induced Inflammasome Activation in Macrophages. ACS Appl. Mater. Interfaces 2018, 10, 41197–41206.
  72. Zafar, H.; Raza, F.; Ma, S.; Wei, Y.; Zhang, J.; Shen, Q. Recent progress on nanomedicine-induced ferroptosis for cancer therapy. Biomater. Sci. 2021, 9, 5092–5115.
  73. Gao, J.; Zhou, H.; Zhao, Y.; Lu, L.; Zhang, J.; Cheng, W.; Song, X.; Zheng, Y.; Chen, C.; Tang, J. Time-course effect of ultrasmall superparamagnetic iron oxide nanoparticles on intracellular iron metabolism and ferroptosis activation. Nanotoxicology 2021, 15, 366–379.
  74. Yang, Y.; Wang, Y.; Guo, L.; Gao, W.; Tang, T.-L.; Yan, M. Interaction between macrophages and ferroptosis. Cell Death Dis. 2022, 13, 355.
  75. Wen, J.; Chen, H.; Ren, Z.; Zhang, P.; Chen, J.; Jiang, S. Ultrasmall iron oxide nanoparticles induced ferroptosis via Beclin1/ATG5-dependent autophagy pathway. Nano Converg. 2021, 8, 10.
  76. Fernández-Acosta, R.; Iriarte-Mesa, C.; Alvarez-Alminaque, D.; Hassannia, B.; Wiernicki, B.; Díaz-García, A.M.; Vandenabeele, P.; Vanden Berghe, T.; Pardo Andreu, G.L. Novel Iron Oxide Nanoparticles Induce Ferroptosis in a Panel of Cancer Cell Lines. Molecules 2022, 27, 3970.
  77. Iriarte-Mesa, C.; Díaz-Castañón, S.; Abradelo, D.G. Facile immobilization of Trametes versicolor laccase on highly monodisperse superparamagnetic iron oxide nanoparticles. Colloids Surf. B Biointerfaces 2019, 181, 470–479.
  78. Wu, C.; Shen, Z.; Lu, Y.; Sun, F.; Shi, H. p53 Promotes Ferroptosis in Macrophages Treated with Fe3O4 Nanoparticles. ACS Appl. Mater. Interfaces 2022, 14, 42791–42803.
  79. Sullivan, K.D.; Galbraith, M.D.; Andrysik, Z.; Espinosa, J.M. Mechanisms of transcriptional regulation by p53. Cell Death Differ. 2018, 25, 133–143.
  80. Zhang, C.; Bu, W.; Ni, D.; Zhang, S.; Li, Q.; Yao, Z.; Zhang, J.; Yao, H.; Wang, Z.; Shi, J. Synthesis of Iron Nanometallic Glasses and Their Application in Cancer Therapy by a Localized Fenton Reaction. Angew. Chem. Int. Ed. 2016, 55, 2101–2106.
  81. Ye, S.; Hananya, N.; Green, O.; Chen, H.; Zhao, A.Q.; Shen, J.; Shabat, D.; Yang, D. A Highly Selective and Sensitive Chemiluminescent Probe for Real-Time Monitoring of Hydrogen Peroxide in Cells and Animals. Angew. Chem. Int. Ed. 2020, 59, 14326–14330.
  82. Huo, M.; Wang, L.; Chen, Y.; Shi, J. Tumor-selective catalytic nanomedicine by nanocatalyst delivery. Nat. Commun. 2017, 8, 357.
  83. Feng, W.; Han, X.; Wang, R.; Gao, X.; Hu, P.; Yue, W.; Chen, Y.; Shi, J. Nanocatalysts-Augmented and Photothermal-Enhanced Tumor-Specific Sequential Nanocatalytic Therapy in Both NIR-I and NIR-II Biowindows. Adv. Mater. 2019, 31, 1805919.
  84. Dong, S.; Dong, Y.; Jia, T.; Zhang, F.; Wang, Z.; Feng, L.; Sun, Q.; Gai, S.; Yang, P. Sequential Catalytic, Magnetic Targeting Nanoplatform for Synergistic Photothermal and NIR-Enhanced Chemodynamic Therapy. Chem. Mater. 2020, 32, 9868–9881.
  85. Zhao, Z.; Wang, W.; Li, C.; Zhang, Y.; Yu, T.; Wu, R.; Zhao, J.; Liu, Z.; Liu, J.; Yu, H. Reactive Oxygen Species–Activatable Liposomes Regulating Hypoxic Tumor Microenvironment for Synergistic Photo/Chemodynamic Therapies. Adv. Funct. Mater. 2019, 29, 1905013.
  86. Pignatello, J.J.; Oliveros, E.; MacKay, A. Advanced Oxidation Processes for Organic Contaminant Destruction Based on the Fenton Reaction and Related Chemistry. Crit. Rev. Environ. Sci. Technol. 2006, 36, 1–84.
  87. Shi, L.; Wang, Y.; Zhang, C.; Zhao, Y.; Lu, C.; Yin, B.; Yang, Y.; Gong, X.; Teng, L.; Liu, Y.; et al. An Acidity-Unlocked Magnetic Nanoplatform Enables Self-Boosting ROS Generation through Upregulation of Lactate for Imaging-Guided Highly Specific Chemodynamic Therapy. Angew. Chem. Int. Ed. 2021, 60, 9562–9572.
  88. Li, M.; Huo, L.; Zeng, J.; Zhu, G.; Shi, S.; Liu, X.; Zhu, X.; Huang, G.; Qiu, D.; Jia, J.; et al. Surface engineered iron oxide nanozyme for synergistic chemodynamic/photodynamic therapy with glutathione depletion and hypoxia relief. Chem. Eng. J. 2022, 440, 135966.
  89. Chen, T.; Chu, Q.; Li, M.; Han, G.; Li, X. Fe3O4@Pt nanoparticles to enable combinational electrodynamic/chemodynamic therapy. J. Nanobiotechnol. 2021, 19, 206.
  90. Ma, X.; Wang, Y.; Liu, X.-L.; Ma, H.; Li, G.; Li, Y.; Gao, F.; Peng, M.; Fan, H.M.; Liang, X.-J. Fe3O4–Pd Janus nanoparticles with amplified dual-mode hyperthermia and enhanced ROS generation for breast cancer treatment. Nanoscale Horiz. 2019, 4, 1450–1459.
  91. Sztandera, K.; Gorzkiewicz, M.; Klajnert-Maculewicz, B. Nanocarriers in photodynamic therapy—In vitro and in vivo studies. WIREs Nanomed. Nanobiotechnol. 2020, 12, e1509.
  92. Lan, M.; Zhao, S.; Liu, W.; Lee, C.; Zhang, W.; Wang, P. Photosensitizers for Photodynamic Therapy. Adv. Healthc. Mater. 2019, 8, 1900132.
  93. Fan, W.; Huang, P.; Chen, X. Overcoming the Achilles’ heel of photodynamic therapy. Chem. Soc. Rev. 2016, 45, 6488–6519.
  94. Mfouo-Tynga, I.S.; Dias, L.D.; Inada, N.M.; Kurachi, C. Features of third generation photosensitizers used in anticancer photodynamic therapy: Review. Photodiagn. Photodyn. Ther. 2021, 34, 102091.
  95. Li, B.; Lin, L. Internal light source for deep photodynamic therapy. Light Sci. Appl. 2022, 11, 85.
  96. Plaetzer, K.; Krammer, B.; Berlanda, J.; Berr, F.; Kiesslich, T. Photophysics and photochemistry of photodynamic therapy: Fundamental aspects. Lasers Med. Sci. 2009, 24, 259–268.
  97. Fisher, C.; Ali, Z.; Detsky, J.; Sahgal, A.; David, E.; Kunz, M.; Akens, M.; Chow, E.; Whyne, C.; Burch, S.; et al. Photodynamic Therapy for the Treatment of Vertebral Metastases: A Phase I Clinical Trial. Clin. Cancer Res. 2019, 25, 5766–5776.
  98. Zhi, D.; Yang, T.; Yang, J.; Fu, S.; Zhang, S. Targeting strategies for superparamagnetic iron oxide nanoparticles in cancer therapy. Acta Biomater. 2020, 102, 13–34.
  99. Li, T.-F.; Xu, H.-Z.; Xu, Y.-H.; Yu, T.-T.; Tang, J.-M.; Li, K.; Wang, C.; Peng, X.-C.; Li, Q.-R.; Sang, X.-Y.; et al. Efficient Delivery of Chlorin e6 by Polyglycerol-Coated Iron Oxide Nanoparticles with Conjugated Doxorubicin for Enhanced Photodynamic Therapy of Melanoma. Mol. Pharm. 2021, 18, 3601–3615.
  100. Estelrich, J.; Busquets, M. Iron Oxide Nanoparticles in Photothermal Therapy. Molecules 2018, 23, 1567.
  101. Chinnathambi, S.; Shirahata, N. Recent advances on fluorescent biomarkers of near-infrared quantum dots for in vitro and in vivo imaging. Sci. Technol. Adv. Mater. 2019, 20, 337–355.
  102. Lyu, Y.; Li, J.; Pu, K. Second Near-Infrared Absorbing Agents for Photoacoustic Imaging and Photothermal Therapy. Small Methods 2019, 3, 1900553.
  103. Lozano-Pedraza, C.; Plaza-Mayoral, E.; Espinosa, A.; Sot, B.; Serrano, A.; Salas, G.; Blanco-Andujar, C.; Cotin, G.; Felder-Flesch, D.; Begin-Colin, S.; et al. Assessing the parameters modulating optical losses of iron oxide nanoparticles under near infrared irradiation. Nanoscale Adv. 2021, 3, 6490–6502.
  104. Amatya, R.; Hwang, S.; Park, T.; Min, K.A.; Shin, M.C. In Vitro and In Vivo Evaluation of PEGylated Starch-Coated Iron Oxide Nanoparticles for Enhanced Photothermal Cancer Therapy. Pharmaceutics 2021, 13, 871.
  105. Dheyab, M.A.; Aziz, A.A.; Jameel, M.S.; Khaniabadi, P.M.; Mehrdel, B.; Khaniabadi, B.M. Gold-coated iron oxide nanoparticles as a potential photothermal therapy agent to enhance eradication of breast cancer cells. J. Phys. Conf. Ser. 2020, 1497, 012003.
  106. Wang, J.; Mei, T.; Liu, Y.; Zhang, Y.; Zhang, Z.; Hu, Y.; Wang, Y.; Wu, M.; Yang, C.; Zhong, X.; et al. Dual-targeted and MRI-guided photothermal therapy via iron-based nanoparticles-incorporated neutrophils. Biomater. Sci. 2021, 9, 3968–3978.
  107. Alterio, D.; Marvaso, G.; Ferrari, A.; Volpe, S.; Orecchia, R.; Jereczek-Fossa, B.A. Modern radiotherapy for head and neck cancer. Semin. Oncol. 2019, 46, 233–245.
  108. Cheng, M.; Jolly, S.; Quarshie, W.O.; Kapadia, N.; Vigneau, F.D.; Kong, F.-M. Modern Radiation Further Improves Survival in Non-Small Cell Lung Cancer: An Analysis of 288,670 Patients. J. Cancer 2019, 10, 168–177.
  109. Brown, S.; Banfill, K.; Aznar, M.C.; Whitehurst, P.; Faivre Finn, C. The evolving role of radiotherapy in non-small cell lung cancer. Br. J. Radiol. 2019, 92, 20190524.
  110. Biau, J.; Chautard, E.; Verrelle, P.; Dutreix, M. Altering DNA Repair to Improve Radiation Therapy: Specific and Multiple Pathway Targeting. Front. Oncol. 2019, 9, 1009.
  111. Hall, S.; Rudrawar, S.; Zunk, M.; Bernaitis, N.; Arora, D.; McDermott, C.; Anoopkumar-Dukie, S. Protection against Radiotherapy-Induced Toxicity. Antioxidants 2016, 5, 22.
  112. Huang, R.-X.; Zhou, P.-K. DNA damage response signaling pathways and targets for radiotherapy sensitization in cancer. Sig. Transduct. Target. Ther. 2020, 5, 60.
  113. Reisz, J.A.; Bansal, N.; Qian, J.; Zhao, W.; Furdui, C.M. Effects of Ionizing Radiation on Biological Molecules—Mechanisms of Damage and Emerging Methods of Detection. Antioxid. Redox Signal. 2014, 21, 260–292.
  114. Catalá, A.; Díaz, M. Editorial: Impact of Lipid Peroxidation on the Physiology and Pathophysiology of Cell Membranes. Front. Physiol. 2016, 7, 423.
  115. Ye, L.F.; Chaudhary, K.R.; Zandkarimi, F.; Harken, A.D.; Kinslow, C.J.; Upadhyayula, P.S.; Dovas, A.; Higgins, D.M.; Tan, H.; Zhang, Y.; et al. Radiation-Induced Lipid Peroxidation Triggers Ferroptosis and Synergizes with Ferroptosis Inducers. ACS Chem. Biol. 2020, 15, 469–484.
  116. Jiang, H.; Wang, H.; De Ridder, M. Targeting antioxidant enzymes as a radiosensitizing strategy. Cancer Lett. 2018, 438, 154–164.
  117. Jia, S.; Ge, S.; Fan, X.; Leong, K.W.; Ruan, J. Promoting reactive oxygen species generation: A key strategy in nanosensitizer-mediated radiotherapy. Nanomedicine 2021, 16, 759–778.
  118. De Kruijff, R.M. FLASH radiotherapy: Ultra-high dose rates to spare healthy tissue. Int. J. Radiat. Biol. 2020, 96, 419–423.
  119. Lacas, B.; Bourhis, J.; Overgaard, J.; Zhang, Q.; Grégoire, V.; Nankivell, M.; Zackrisson, B.; Szutkowski, Z.; Suwiński, R.; Poulsen, M.; et al. Role of radiotherapy fractionation in head and neck cancers (MARCH): An updated meta-analysis. Lancet Oncol. 2017, 18, 1221–1237.
  120. Hegemann, N.-S.; Guckenberger, M.; Belka, C.; Ganswindt, U.; Manapov, F.; Li, M. Hypofractionated radiotherapy for prostate cancer. Radiat. Oncol. 2014, 9, 275.
  121. Hughes, J.R.; Parsons, J.L. FLASH Radiotherapy: Current Knowledge and Future Insights Using Proton-Beam Therapy. Int. J. Mol. Sci. 2020, 21, 6492.
  122. Mohan, R.; Grosshans, D. Proton therapy—Present and future. Adv. Drug Deliv. Rev. 2017, 109, 26–44.
  123. Howard, D.; Sebastian, S.; Le, Q.V.-C.; Thierry, B.; Kempson, I. Chemical Mechanisms of Nanoparticle Radiosensitization and Radioprotection: A Review of Structure-Function Relationships Influencing Reactive Oxygen Species. Int. J. Mol. Sci. 2020, 21, 579.
  124. Liu, Y.; Zhang, P.; Li, F.; Jin, X.; Li, J.; Chen, W.; Li, Q. Metal-based NanoEnhancers for Future Radiotherapy: Radiosensitizing and Synergistic Effects on Tumor Cells. Theranostics 2018, 8, 1824–1849.
  125. Peukert, D.; Kempson, I.; Douglass, M.; Bezak, E. Metallic nanoparticle radiosensitisation of ion radiotherapy: A review. Phys. Med. 2018, 47, 121–128.
  126. Abdul Rashid, R.; Zainal Abidin, S.; Khairil Anuar, M.A.; Tominaga, T.; Akasaka, H.; Sasaki, R.; Kie, K.; Abdul Razak, K.; Pham, B.T.T.; Hawkett, B.S.; et al. Radiosensitization effects and ROS generation by high Z metallic nanoparticles on human colon carcinoma cell (HCT116) irradiated under 150 MeV proton beam. OpenNano 2019, 4, 100027.
  127. Choi, J.; Kim, G.; Cho, S.B.; Im, H.-J. Radiosensitizing high-Z metal nanoparticles for enhanced radiotherapy of glioblastoma multiforme. J. Nanobiotechnol. 2020, 18, 122.
  128. Talik Sisin, N.N.; Abdul Razak, K.; Zainal Abidin, S.; Che Mat, N.F.; Abdullah, R.; Ab Rashid, R.; Khairil Anuar, M.A.; Mohd Zainudin, N.H.; Tagiling, N.; Mat Nawi, N.; et al. Radiosensitization Effects by Bismuth Oxide Nanoparticles in Combination with Cisplatin for High Dose Rate Brachytherapy. Int. J. Nanomed. 2019, 14, 9941–9954.
  129. Vilotte, F.; Jumeau, R.; Bourhis, J. High Z nanoparticles and radiotherapy: A critical view. Lancet Oncol. 2019, 20, e557.
  130. Guerra, D.B.; Oliveira, E.M.N.; Sonntag, A.R.; Sbaraine, P.; Fay, A.P.; Morrone, F.B.; Papaléo, R.M. Intercomparison of radiosensitization induced by gold and iron oxide nanoparticles in human glioblastoma cells irradiated by 6 MV photons. Sci. Rep. 2022, 12, 9602.
  131. Hwang, C.; Kim, J.M.; Kim, J. Influence of concentration, nanoparticle size, beam energy, and material on dose enhancement in radiation therapy. J. Radiat. Res. 2017, 58, 405–411.
  132. Emerit, J.; Beaumont, C.; Trivin, F. Iron metabolism, free radicals, and oxidative injury. Biomed. Pharmacother. 2001, 55, 333–339.
  133. Hauser, A.K.; Mitov, M.I.; Daley, E.F.; McGarry, R.C.; Anderson, K.W.; Hilt, J.Z. Targeted iron oxide nanoparticles for the enhancement of radiation therapy. Biomaterials 2016, 105, 127–135.
  134. Klein, S.; Kızaloğlu, M.; Portilla, L.; Park, H.; Rejek, T.; Hümmer, J.; Meyer, K.; Hock, R.; Distel, L.V.R.; Halik, M.; et al. Enhanced In Vitro Biocompatibility and Water Dispersibility of Magnetite and Cobalt Ferrite Nanoparticles Employed as ROS Formation Enhancer in Radiation Cancer Therapy. Small 2018, 14, 1704111.
  135. Shetake, N.G.; Kumar, A.; Pandey, B.N. Iron-oxide nanoparticles target intracellular HSP90 to induce tumor radio-sensitization. Biochim. Biophys. Acta BBA-Gen. Subj. 2019, 1863, 857–869.
  136. He, C.; Jiang, S.; Jin, H.; Chen, S.; Lin, G.; Yao, H.; Wang, X.; Mi, P.; Ji, Z.; Lin, Y.; et al. Mitochondrial electron transport chain identified as a novel molecular target of SPIO nanoparticles mediated cancer-specific cytotoxicity. Biomaterials 2016, 83, 102–114.
  137. Stanković, A.; Mihailović, J.; Mirković, M.; Radović, M.; Milanović, Z.; Ognjanović, M.; Janković, D.; Antić, B.; Mijović, M.; Vranješ-Đurić, S.; et al. Aminosilanized flower-structured superparamagnetic iron oxide nanoparticles coupled to 131I-labeled CC49 antibody for combined radionuclide and hyperthermia therapy of cancer. Int. J. Pharm. 2020, 587, 119628.
  138. Żuk, M.; Podgórski, R.; Ruszczyńska, A.; Ciach, T.; Majkowska-Pilip, A.; Bilewicz, A.; Krysiński, P. Multifunctional Nanoparticles Based on Iron Oxide and Gold-198 Designed for Magnetic Hyperthermia and Radionuclide Therapy as a Potential Tool for Combined HER2-Positive Cancer Treatment. Pharmaceutics 2022, 14, 1680.
  139. Lin, H.; Yin, L.; Chen, B.; Ji, Y. Design of functionalized magnetic silica multi-core composite nanoparticles for synergistic magnetic hyperthermia/radiotherapy in cancer cells. Colloids Surf. B Biointerfaces 2022, 219, 112814.
More
© Text is available under the terms and conditions of the Creative Commons Attribution (CC BY) license; additional terms may apply. By using this site, you agree to the Terms and Conditions and Privacy Policy.
This entry is offline, you can click here to edit this entry!
ScholarVision Creations
Feedback