中文摘要：

目的：探讨miR-520a在结肠腺瘤性息肉、结肠癌及癌旁组织中的表达变化,并分析miR-520a在结肠癌中的表达与临床病理特征的关系。方法：采用实时荧光定量PCR（qRT-PCR）检测30例结肠腺瘤组织和55例结肠癌及其癌旁组织中miR-520a的表达,分析结肠癌中miR-520a的表达与临床病理特征之间的关系。结果：miR-520a在结肠癌组织中的表达明显低于结肠腺瘤,而结肠腺瘤中的表达明显低于癌旁组织（P〈0.05）。在结肠癌中,miR-520a的表达与肿瘤分化程度、淋巴转移、TNM分期、远处转移均显著相关（P〈0.05）。结论：miR-520a在结肠癌中低表达,提示其可能发挥抑癌基因的功能。

英文摘要：

Objective： To study the expression and clinical significance of miR- 520 a in adenomatous polyps and colon cancer. Methods： Expression of miR- 520 a was detected by quantitative real time PCR（ qRT- PCR） in 30 patients with adenomatous polyps and 55 patients with colon cancer compared with non- tumor adjacent tissues（ NAT）.The relationship between its expression in colon cancer and clinical features were analyzed. Results： The expression level of miR- 520 a in colon cancer was significantly lower than that of adenomatous polyps,and the expression of miR- 520 a in adenomatous polyps was lower than that of NAT. Further,the low expression of miR- 520 a was significantly related to tumor differentiation,lymph node metastasis,distant metastasis,and TNM stage. Conclusion： miR- 520 a lowly expressed in colon cancer,which implicated it might play as a tumor suppressor gene in the colon cancer development.