Expression level of miR-199b in human colorectal cancer tissues and its correlation with clinicopathological features and prognosis of patients / 中华肿瘤杂志

ABSTRACT

Objective: To investigate the relationship between miR-199b and clinicopathologic features and prognosis of patients with colorectal cancer. Methods: Cancer tissues and adjacent normal tissues of 202 patients with colorectal cancer treated in Cancer Hospital of Chinese Academy of Medical Sciences from March to December 2011 were collected. Reverse transcription-quantitative real-time polymerase chain reaction was used to detect the expression level of miR-199b in colorectal cancer tissues and corresponding adjacent normal tissues. Kaplan-Meier method and Log rank test were used for survival analysis, and receiver operating characteristic (ROC) curve was used to evaluate the prognostic value of miR-199b in colorectal cancer patients. Results: The relative expression level of miR-199b in colorectal cancer tissues (-7.88±0.11) was lower than that in adjacent normal tissues (-6.49±0.12, P<0.001). The expression level of miR-199b in colorectal cancer tissues with lymph node metastasis (-7.51±0.14) was higher than that in colorectal cancer tissues without lymph node metastasis (-8.23±0.17, P<0.001). The relative expression levels of miR-199b in stage Ⅰ/Ⅱ, Ⅲ and Ⅳ colorectal cancer tissues were gradually increased, which were -8.26±0.17, -7.70±0.16 and -6.57±0.27, respectively, and the difference was statistically significant (P<0.001). The 5-year survival rates of patients with high and low expressions of miR-199b were 75.6% and 84.6%(P=0.045) respectively. ROC curve showed that when miR-199b was -7.965, the area under the curve was 0.578 (95% CI 0.468, 0.688). Conclusion: The high expression of miR-199b in colorectal cancer tissues is associated with late TNM stage, lymph node metastasis and poor prognosis in colorectal cancer patients, and miR-199b may be used as a potential marker for postoperative progress and prognosis in colorectal cancer patients.