TGFB1 and colorectal cancer: Although TGFβ can have tumor-suppressive functions, acting as a potent inhibitor of normal colonic epithelial cells, it can also have tumor-promoting functions promoting the survival, invasion, and metastasis of colorectal cancer cells, and is known as a tumor promotor in the last stages of colorectal cancer through its immunosuppressive function (77, 87–89).