Low expression of claudin-1 and presence of poorly-differentiated tumor clusters correlate with poor prognosis in colorectal cancer.

BACKGROUND

Claudins are integral membrane proteins that constitute tight junctions. The aim of this study was to determine the clinical significance of claudin-1 in terms of the cell-cell adhesion, considering the poorly-differentiated tumor component.

PATIENTS AND METHODS

A total of 344 cases of stage II and III colorectal cancer were enrolled. We evaluated the expression of claudin-1 by immunohistochemistry and the extent of the poorly differentiated component.

RESULTS

Low expression of claudin-1 was associated with lymphatic involvement, histological differentiation, extent of poorly-differentiated component, reduced disease-free and overall survival. Multivariate analysis indicated that lymph node metastasis, venous involvement and low claudin-1 expression were independent predictors of recurrence, and that lymph node metastasis, venous involvement and low claudin-1 expression were associated with poor survival.

CONCLUSION

Our study not only showed the significance of low expression of claudin-1 as a predictor of poor prognosis of colorectal cancer but also supported the concept of grading of the poorly-differentiated component.