[Expression characteristics of PTEN and NDRG1 in colorectal carcinoma and their prognostic value]

Objective: To study the expression status and clinical significance of PTEN and NDRG1 in colorectal carcinoma. Methods: Tissue samples of 91 colorectal cancers, 30 colorectal adenomas and 21 colorectal normal mucosa tissues were collected. Postoperative specimens were examined by immunohistochemistry for PTEN and NDRG1 expression. The expression of PTEN and NDRG1 was correlated with clinicopathological feature. Results: The expression of PTEN and NDRG1 in the studied cases was detected in 55.0%(50/91) and 76.9%(70/91), respectively. Their expression was significantly different from that of colorectal adenomas and normal colorectal mucosa tissues(P<0.05). Decreased expression of PTEN and over expression of NDRG1 were significantly related to the lymph node metastasis (P<0.05). The expression of PTEN was negatively related to that of NDRG1 in colorectal carcinoma(r_s'=-0.251, P=0.016). The patients with negative expression of PTEN showed a lower disease free survival and overall survival(P<0.05). Conclusions: Loss of expression of PTEN protein may be an important molecular marker in predicting the occurrence and PTEN may be useful as a prognostic marker of colorectal carcinoma. NDRG1 plays a role in the development of colorectal carcinoma, although not a prognostic indicator.The ancillary study with combined detection of PTEN and NDRG1 may be useful in difficult cases.