Mammalian Target of Rapamycin Inhibitors, often referred to as mTOR inhibitors, are a class of drugs that block the activity of the mTOR protein. This protein plays a crucial role in regulating cell growth, proliferation, and survival. By inhibiting mTOR, these drugs can slow down the growth of certain types of cancer cells and are used in various therapeutic settings, including organ transplantation and cancer treatment. These inhibitors, such as everolimus and temsirolimus, are particularly effective in treating specific cancers like renal cell carcinoma and certain types of breast cancer. They can also help prevent organ rejection in transplant patients by suppressing the immune response. However, like all medications, mTOR inhibitors can have side effects and require careful monitoring.