Decreased expression of claudin-1 in rectal cancer: a factor for recurrence and poor prognosis.

AIM

To investigate the potential involvement of claudin-1 (CL-1) in the tumorigenesis of rectal cancer by analyzing the correlation between CL-1 expression, clinicopathological factors and prognosis.

PATIENTS AND METHODS

Rectal cancer tissue specimens from 306 patients that had undergone surgical treatment were evaluated using immunohistochemical analysis for expression of CL-1 and correlated with clinicopathological factors.

RESULTS

A reduced expression of CL-1 (less than 30% of tumor cells strongly, positively stained) correlated significantly with poor prognosis in stage II and III rectal cancer. Moreover, the expression levels of CL-1 correlated significantly with tumor differentiation and perineural invasion (p=0.037 and 0.009, respectively). However, no significant differences were detected between the expression levels of CL-1 and other clinicopathological factors.

CONCLUSION

Loss of claudin-1 expression is a strong predictor of disease recurrence and poor patient survival in stage II and III rectal cancer.