CDKN1A and colorectal cancer: Furthermore, the upregulation of p21 leads to changes in cell behavior; in colorectal cancer, HCC, prostate cancer, and renal cell carcinoma cell lines, p21 upregulation results in more cells residing in G0 or G1 phase of the cell cycle,6,7,8,64 as well as a decrease in migrative and invasive capabilities in prostate cancer cell lines.8