The expression of ICAM-1 determines the malignant potential of colorectal cancer; it is correlated with a worse prognosis [90,91], although there are also studies indicating that the membrane expression of this molecule correlates with better prognosis of colorectal cancer [92], which is explained by the possibility that ICAM-1 expression on the membrane of tumor cells stimulates the killing of tumor cells by cytotoxic lymphocytes, if they are present in the tumor microenvironment. This evidence concerns the gene ICAM1 and colorectal cancer.