CD155 knockdown promotes apoptosis via AKT/Bcl-2/Bax in colon cancer cells.

CD155, one of the nectin-like molecule family members, is involved in cell adhesion and motility. CD155 is overexpressed in several human cancers, but its role in proliferation and apoptosis of colorectal cancer remains unclear. We found that CD155 was up-regulated in colorectal cancer tissues. CD155 knockdown via shRNA lentiviruses inhibited colon cancers cell migration and invasion, with a reduction in the expression of FAK, Src and MMP-2. CD155 down-regulation also suppressed colon cancer cell proliferation, accompanied by changing expressions of some molecules related to cell cycle. Finally, CD155 knockdown increased the expression ratio between Bax and Bcl-2, resulting in a significant increase in colon cancer cell apoptosis. Taken together, these results demonstrate that CD155 is involved in not only migration and invasion but also proliferation and survival abilities of colon cancer cells, suggesting that CD155 is one of key molecules promoting the growth and metastasis of colorectal cancer.