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The NOTCH1 gene provides instructions for making a protein called Notch1, a member of the Notch family of receptors. Receptor proteins have specific sites into which certain other proteins, called ligands, fit like keys into locks. Attachment of a ligand to the Notch1 receptor sends signals that are important for normal development of many tissues throughout the body, both before birth and after. Notch1 signaling helps determine the specialization of cells into certain cell types that perform particular functions in the body (cell fate determination). It also plays a role in cell growth and division (proliferation), maturation (differentiation), and self-destruction (apoptosis).
The protein produced from the NOTCH1 gene has such diverse functions that the gene is considered both an oncogene and a tumor suppressor. Oncogenes typically promote cell proliferation or survival, and when mutated, they have the potential to cause normal cells to become cancerous. In contrast, tumor suppressors keep cells from growing and dividing too fast or in an uncontrolled way, preventing the development of cancer; mutations that impair tumor suppressors can lead to cancer development.
2. Health Conditions Related to Genetic Changes
2.1. Adams-Oliver syndrome
At least 15 mutations in the NOTCH1 gene have been found to cause Adams-Oliver syndrome, a condition characterized by areas of missing skin (aplasia cutis congenita), usually on the scalp, and malformations of the hands and feet. These mutations are usually inherited and are present in every cell of the body. Some of the NOTCH1 gene mutations involved in Adams-Oliver syndrome lead to production of an abnormally short protein that is likely broken down quickly, causing a shortage of Notch1. Other mutations change single protein building blocks (amino acids) in the Notch1 protein. These changes are thought to alter the structure of the protein, impairing its ability to function. Loss of Notch1 signaling may underlie blood vessel and heart abnormalities in people with Adams-Oliver syndrome. However, while these types of abnormalities are more common in affected individuals with NOTCH1 gene mutations than in those with a different gene mutation, some people with Notch1-related Adams-Oliver syndrome do not have blood vessel or heart abnormalities. It is not clear how loss of Notch1 function leads to the scalp and limb abnormalities characteristic of the condition. Researchers suggest these features may be due to abnormal blood vessel development before birth.
2.2. Head and neck squamous cell carcinoma
Mutations in the NOTCH1 gene have been found in about 15 percent of head and neck squamous cell carcinomas (HNSCC). This type of cancerous tumor occurs in the moist lining of the mouth, nose, and throat. NOTCH1 gene mutations associated with this condition are acquired during a person's lifetime and are found only in tumor cells; these changes are known as somatic mutations. Mutations in the NOTCH1 gene may reduce or eliminate production of functional Notch1 protein or lead to production of a protein that is unable to participate in cell signaling. Without the tumor suppressor function of the Notch1 protein, cells can grow and divide without control, leading to tumor formation.
2.3. Other disorders
Mutations in the NOTCH1 gene can impair normal heart development before birth, causing abnormalities of the heart and related structures. One such abnormality occurs in the valve that connects the aorta to the heart (the aortic valve). The aorta is the large blood vessel that distributes blood from the heart to the rest of the body. The aortic valve normally has three flaps, or cusps, that open to let blood leave the heart and come together to prevent blood from reentering the heart. However, in about 1 to 2 percent of people, the aortic valve has only two flaps, which is known as a bicuspid aortic valve. NOTCH1 gene mutations appear to be involved in 4 to 10 percent of bicuspid aortic valve cases.
Individuals with a bicuspid aortic valve are at a higher than normal risk of developing other aortic abnormalities, such as a bulge in the wall of the aorta (thoracic aortic aneurysm) or a sudden tearing of the layers in the aorta wall (aortic dissection). In addition, accumulation of calcium on the aortic valve can occur in people with a bicuspid aortic valve. Researchers suspect that NOTCH1 gene mutations also play a role in the development of thoracic aortic aneurysms and in calcification of the valve.
NOTCH1 gene mutations are also involved in critical congenital heart disease. Individuals with this condition have one or more specific heart abnormalities that affect the flow of blood into, out of, or through the heart. Some of the heart defects involve structures within the heart itself, such as the two lower chambers of the heart (the ventricles) or the valves that control blood flow through the heart. Others affect the structure of the large blood vessels leading into and out of the heart (including the aorta and pulmonary artery). Still others involve a combination of these structural abnormalities.
2.4. Other cancers
NOTCH1 gene mutations have been found in other types of cancer, particularly blood cell cancers called T-cell acute lymphoblastic leukemia and chronic lymphocytic leukemia, and a type of lung cancer called non-small cell lung cancer. Unlike in HNSCC (described above), the NOTCH1 gene mutations found in these cancers abnormally turn on (activate) Notch1 signaling. The increased activity can lead to uncontrolled cell growth and division, which can result in the development of cancer. Researchers are working to understand how both activating and inactivating NOTCH1 gene mutations can lead to cancer development.
3. Other Names for This Gene
- neurogenic locus notch homolog protein 1
- neurogenic locus notch homolog protein 1 preproprotein
- Notch homolog 1, translocation-associated
- translocation-associated notch protein TAN-1
This entry is adapted from https://medlineplus.gov/genetics/gene/notch1
- Agrawal N, Frederick MJ, Pickering CR, Bettegowda C, Chang K, Li RJ, Fakhry C,Xie TX, Zhang J, Wang J, Zhang N, El-Naggar AK, Jasser SA, Weinstein JN, Treviño L, Drummond JA, Muzny DM, Wu Y, Wood LD, Hruban RH, Westra WH, Koch WM, Califano JA, Gibbs RA, Sidransky D, Vogelstein B, Velculescu VE, Papadopoulos N, WheelerDA, Kinzler KW, Myers JN. Exome sequencing of head and neck squamous cellcarcinoma reveals inactivating mutations in NOTCH1. Science. 2011 Aug26;333(6046):1154-7. doi: 10.1126/science.1206923.
- Arruga F, Gizdic B, Serra S, Vaisitti T, Ciardullo C, Coscia M, Laurenti L,D'Arena G, Jaksic O, Inghirami G, Rossi D, Gaidano G, Deaglio S. Functionalimpact of NOTCH1 mutations in chronic lymphocytic leukemia. Leukemia. 2014May;28(5):1060-70. doi: 10.1038/leu.2013.319.
- Dotto GP. Notch tumor suppressor function. Oncogene. 2008 Sep1;27(38):5115-23. doi: 10.1038/onc.2008.225. Review.
- Lobry C, Oh P, Aifantis I. Oncogenic and tumor suppressor functions of Notchin cancer: it's NOTCH what you think. J Exp Med. 2011 Sep 26;208(10):1931-5. doi:10.1084/jem.20111855. Review.
- Loyo M, Li RJ, Bettegowda C, Pickering CR, Frederick MJ, Myers JN, Agrawal N. Lessons learned from next-generation sequencing in head and neck cancer. HeadNeck. 2013 Mar;35(3):454-63. doi: 10.1002/hed.23100.
- McKellar SH, Tester DJ, Yagubyan M, Majumdar R, Ackerman MJ, Sundt TM 3rd.Novel NOTCH1 mutations in patients with bicuspid aortic valve disease andthoracic aortic aneurysms. J Thorac Cardiovasc Surg. 2007 Aug;134(2):290-6.
- Southgate L, Sukalo M, Karountzos ASV, Taylor EJ, Collinson CS, Ruddy D, SnapeKM, Dallapiccola B, Tolmie JL, Joss S, Brancati F, Digilio MC, Graul-Neumann LM, Salviati L, Coerdt W, Jacquemin E, Wuyts W, Zenker M, Machado RD, Trembath RC.Haploinsufficiency of the NOTCH1 Receptor as a Cause of Adams-Oliver SyndromeWith Variable Cardiac Anomalies. Circ Cardiovasc Genet. 2015 Aug;8(4):572-581.doi: 10.1161/CIRCGENETICS.115.001086.
- Stittrich AB, Lehman A, Bodian DL, Ashworth J, Zong Z, Li H, Lam P, KhromykhA, Iyer RK, Vockley JG, Baveja R, Silva ES, Dixon J, Leon EL, Solomon BD, GlusmanG, Niederhuber JE, Roach JC, Patel MS. Mutations in NOTCH1 cause Adams-Oliversyndrome. Am J Hum Genet. 2014 Sep 4;95(3):275-84. doi:10.1016/j.ajhg.2014.07.011.
- Weng AP, Ferrando AA, Lee W, Morris JP 4th, Silverman LB, Sanchez-Irizarry C, Blacklow SC, Look AT, Aster JC. Activating mutations of NOTCH1 in human T cellacute lymphoblastic leukemia. Science. 2004 Oct 8;306(5694):269-71.