Expression of MicroRNA-7-5p in human colorectal cancer and its influence on proliferation and apoptosis of colon cancer cell CaCo2 / 医学研究生学报

ABSTRACT

Objective　MicroRNAs are differentially expressed in colorectal cancer tumor tissues and adjacent normal tissues, which play an important role in the development of colorectal cancer. This study aims to investigate the expression of microRNA-7-5p in colorectal cancer patients and its influence on the proliferation and apoptosis of colon cancer cell CaCo2.　Methods　The high-throughput microarray was used to screen differentially expressed microRNAs, and real-time quantitative PCR (RT-PCR) was used to detect the expression of microRNA-7-5p in 10 cases of colorectal cancer patients and corresponding adjacent normal tissues. Western blot was performed to detect the expression of intestinal trefoil factor (TFF3) in different tissues and CaCo2 cells after transfection with microRNA-7-5p. The expression of TFF3 in different tissues and CaCo2 cells transfected with microRNA-7-5p was detected. TUNEL combined with flow cytometry was used to detect the apoptosis of CaCo2 cells after transfection. The CCK-8 assay was used to detect the proliferation of CaCo2 cells after transfection.　Results　The relative expression of MicroRNA-7-5p in colorectal cancer tissue was 0.409 ± 0.095, which was significantly lower than that of normal tissue adjacent to cancer (1.000 ± 0.014), and the difference was statistically significant (P <0.01). The relative expression of TFF3 in colorectal cancer tissues was significantly higher than that in normal adjacent tissues (P <0.01). The relative expression of TFF3 in CaCo2 cells decreased in the overexpressed microRNA-7-5p of the control group (0.729 ± 0.041). The proliferation ability (0.930 ± 0.007) was significantly lower in the blank control group (0.990 ± 0.005) (P <0.01), and it could increase the proportion of early apoptotic cells (50.700 ± 0.989) and late apoptotic cells (40.525 ± 0.515).　Conclusion　MicroRNA-7-5p is lowly expressed in colorectal cancer and is associated with the occurrence and development of colorectal cancer. Up-regulated microRNA-7-5p inhibits the proliferation of colon cancer cell CaCo2 and promotes its apoptosis.