Increased nuclear localization of p21(WAF1/CIP1) in SPRY2 downregulated colon cancer cells may explain the inhibition of cell proliferation in colon cancer cells.
To our knowledge, this is the first report showing that cladosporol A inhibits colon cancer cell proliferation by modulating p21(waf1/cip1) expression.
Sulindac has been reported to be effective in suppressing tumor growth through the induction of p21WAF1/cip1 in human, animal models of colon cancer and colon cancer cells.
Thus, p68/p72 may contribute to colon cancer formation by directly up-regulating proto-oncogenes and indirectly by down-regulating the growth suppressor p21(WAF1/CIP1).
In addition, CLP-mediated cell cycle arrest was reduced by the knockout of the p21(WAF1/CIP1) gene in human colon cancer HCT116 cells, suggesting that the cell cycle arrest by CLP was at least partially mediated through the induction of p21(WAF1/CIP1) expression.
Artepillin C appears to prevent colon cancer through the induction of cell-cycle arrest by stimulating the expression of Cip1/p21 and to be a useful chemopreventing factor in colon carcinogenesis.
In the present study, we found that treatment of the cultured human colon cancer cell line COLO-205 with a PKC agonist, 12-O-tetradecanoylphorbol-13-acetate (TPA), resulted in cell-cycle arrest at the G(0)/G(1) phase, decrease in cell number, PKCgamma isoform translocation, and upregulation of p21(Cip1) protein.
We examined the effect of butyrate on the expression of WAF1/Cip1, a potent inhibitor of cyclin-dependent kinases, and its relation to growth arrest in a p53-mutated human colon cancer cell line WiDr.