Correlation of beta-catenin and p53 Protein Expression with Clinico-pathologic Characteristics of Colorectal Cancer

ABSTRACT

PURPOSE: Both the beta-catenin and p53 play a crucial role in the process of colon carcinogenesis. The expression of beta-catenin and/or p53 has been reported to be associated with pathologic features of tumor and prognosis of patients. In addition, several recent studies have suggested a close biological association between p53 expression and nuclear beta-catenin level. We analyzed the pathologic variables and p53 expression according to the intra-nuclear beta-catenin expression in colon cancer to make such assumptions more clear since they are still controversial issues. METHODS: The expressions of beta-catenin, p53 and Ki-67 protein in colon cancer were determined by immunohistochemical staining. The relationship between these protein expressions and tumor characteristics was statistically analyzed. RESULTS: The intra-nuclear beta-catenin accumulation was not associated with any of the pathological variables including lymph node metastasis and tumor differentiation, but it was correlated with higher level of Ki-67 proliferation index (P=0.006) and negative staining of p53 (P=0.015). Positive p53 staining was significantly associated with lymph node metastasis (P=0.006), lymphatic invasion (P=0.03) and venous invasion (P=0.02). CONCLUSION: These results support the suggestion that intra-nuclear accumulation of beta-catenin may regulate the p53 activity in colorectal cancer. In addition, positive staining of p53 may be used as a valuable prognostic indicator since it was strongly associated with lymph node metastasis, lymphatic and venous invasion.