Overexpression of δ-catenin is associated with a malignant phenotype and poor prognosis in colorectal cancer

Little is known regarding the expression or clinical significance of δ-catenin, a member of the catenin family, in colorectal cancer (CRC). The present study examined the expression of δ-catenin using immunohistochemistry in 110 cases of CRC, including 70 cases with complete follow-up records and 40 cases with paired lymph node metastases. In addition, δ-catenin mRNA and protein expression were compared in 30 pairs of matched CRC and normal colorectal tissues by reverse transcription quantitative polymerase chain reaction and western blot analysis. δ-Catenin was weakly expressed or absent in the cytoplasm of normal intestinal epithelial cells, whereas positive δ-catenin expression local-ized to the cytoplasm was observed in CRC cells. The rate of positive δ-catenin expression in CRC (68.18%; 75/110) was significantly higher than that in normal colorectal tissues (36.7%; 11/30; P<0.001). In addition, δ-catenin mRNA and protein expression were significantly increased in CRC tissues compared to those in their matched normal tissues (all P<0.05). The expression of δ-catenin in stage III–IV CRC was higher than that in stage I–II CRC, and the expression of δ-catenin in the tumors of patients with lymph node metastases was higher than that in patients without lymph node metastases. Kaplan-Meier survival curves demonstrated that the survival time of patients with positive δ-catenin expression was shorter than that of patients with negative δ-catenin expression (P=0.005). Furthermore, Cox multivariate analysis indicated that the tumor, nodes and metastasis stage (P=0.02) and positive δ-catenin expression (P=0.033) were independent prognostic factors in CRC. The present study therefore indicated that δ-catenin may be a suitable independent prognostic factor for CRC.