Published online Mar 7, 2016. doi: 10.3748/wjg.v22.i9.2789
Peer-review started: October 1, 2015
First decision: November 13, 2015
Revised: December 14, 2015
Accepted: December 30, 2015
Article in press: December 30, 2015
Published online: March 7, 2016
Core tip: Human cytomegalovirus (HCMV) is strongly correlated to colorectal cancer (CRC), although it remains unclear whether the virus contributes to CRC pathogenesis. We examined the expression of HCMV-encoded US28 protein in 103 CRC patient samples and 98 corresponding adjacent noncancerous samples using immunohistochemistry; the relationship between US28 expression and clinicopathological features was also analyzed. We found that US28 expression differed significantly between colorectal carcinoma and adjacent noncancerous colorectal tissues and that US28 expression was correlated with histological grade, metastasis, Dukes’ stage, and survival. After successful transfection with the US28 gene, LOVO cells exhibited higher viability, greater chemotherapy resistance, accelerated cell cycle progression, and increased invasion. These findings indicate that US28 expression predicts a poor prognosis and may promote the pathogenesis of CRC. Thus, targeting specific HCMV proteins (e.g., US28) in endogenously infected CRC may constitute a novel antitumor approach.