目的： 探讨不同级别结肠癌中miR-33a和基膜聚糖（lumican）基因的表达情况，同时研究miR-33a对于结肠癌细胞侵袭和迁移的影响。方法： 收集2015年1月至2016年1月新乡医学院第一附属医院肿瘤科收治的141例结肠癌患者，Western blotting和qPCR检测不同级别结肠癌组织中miR-33a和lumican的表达情况。使用miR-33a mimic转染人结肠癌细胞SW480，qPCR检测miR-33a mimic转染后细胞miR-33a和lumican mRNA的表达变化情况，使用Transwell侵袭实验检测miR-33a对人结肠癌细胞SW480侵袭能力的影响，使用划痕实验检测miR-33a对人结肠癌细胞SW480迁移能力的影响。裸鼠皮下成瘤实验检测miR-33a对结肠癌移植瘤生长以及裸鼠生存的影响。结果：随着结肠癌肿瘤级别的增加，miR-33a表达明显降低，而lumican表达水平明显增加；随着结肠癌病理分期和分级的增加，miR-33a表达逐渐降低；淋巴结转移的结肠癌组织中miR-33a的表达明显降低。转染miR-33a-mimic可以明显上调miR-33a的表达，上调miR-33a可以显著降低lumican蛋白表达水平、可以抑制结肠癌细胞的侵袭和迁移能力。miR-33a-mimic组荷瘤裸鼠肿瘤增长幅度明显减慢，而荷瘤裸鼠生存期明显延长。结论：miR-33a与结肠癌分期、分级以及是否有淋巴结转移有关，miR-33a可通过下调lumican抑制结肠癌细胞的侵袭和迁移。

Objective:To investigate expression situations of miR-33a and lumican in colon cancer at various stages and to explore effect of miR-33a on invasion and migration of colon cancer cells. Methods: Expression situations of miR-33a and lumican in colon cancer at various sages were detected by Western blotting and qPCR. To up-regulate expression of miR-33a, miR-33a mimic was transfected into colon cancer SW480 line cells. Expressions of miR-33a and lumican mRNAs after the transfection of miR-33a mimic were detected by qPCR. Transwell and scratch assays were used to examine effect of miR-33a on invasion and migration abilities of human colon cancer SW480 line cells respectively. Subcutaneous tumor formation assay in nude mice was used to detect growth of tumor tissues in the colon cancer and survival of the nudemice.Results: With increased tumor stages of the colon cancer, expression of miR-33a obviously decreased, and expression of lumican obviously increased. As increasing pathological stage and grade, expression of miR-33a gradually decreased. Expression of miR-33a evidently decreased in the colon cancer tissues with lymph node metastasis. Using of miR-33a mimic clearly up-regulated expression of miR-33a, which significantly decreased expression of lumican protein. Up-regulation of miR-33a inhibited invasion and migration abilities of the colon cancer cells. Cancer growth extent of the tumor bearing mice in the miR-33a mimic group obviously decreased, and their survival period evidently prolonged. Conclusion: miR-33a could be associated with staging and grading of the colon cancer as well as lymph node metastasis. miR-33a could inhibit invasion and migration of the colon cancer through inhibition of lumican.

河南省卫生厅课题项目（No. 1203068)