The repurposing of drugs is an important and rapidly growing field in the treatment of cancer. The main advantage of drug repurposing is using currently established drugs for various diseases and testing them on newer diseases, such as cancer. This strategy allows drug developers to reduce the time for a drug to be made available after clinical trials and testing by using drugs that have already gone through the process. The key to its use is to target the intricate signalling pathways in cancer, which contribute to the initiation, progression, and severity of cancer. Such pathways, if targeted correctly using repurposed drugs, could result in the regression of the tumour or, in some cases, a potential curative effect.