Mad2 and p27 expression profiles in colorectal cancer and its clinical significance.

AIM

To investigate the expression of tumor suppressor gene p27 and spindle checkpoint gene Mad2 and to demonstrate their expression difference in colorectal cancer and normal mucosa and to evaluate its clinical significance.

METHODS

Immunohistochemical staining was used for detection of expression of Mad2 and p27 in colorectal cancer and its corresponding normal mucosa.

RESULTS

Mad2 was significantly overexpressed in colorectal cancer compared with corresponding normal mucosa (P<0.01, chi(2) = 7.5), and it was related to the differentiation of adenocarcinoma, lymph node metastasis and survival period after excision (P<0.05, chi(2) = 7.72, chi(2) = 4.302, chi(2) = 6.234). The rate of p27 positive expression in adenocarcinomas and normal mucosa was 40% and 80% respectively. There was a significant difference in p27 expression between adenocarcinomas and normal mucosa (P<0.001, chi(2) = 13.333), which was related to the differentiation degree of adenoca rcinoma and lymph node metastasis (P<0.05, chi(2) = 8.901 chi(2) = 4). The positive expression of p27 was not correlated with survival period after excision.

CONCLUSION

Defect of spindle checkpoint gene Mad2 and mutation of p27 gene are involved mainly in colorectal carcinogenesis and associated with prognosis of colorectal cancer.