miR-449a and CDK6 in gastric carcinoma

• Published in: Oncology letters 2014-10, Vol.8 (4), p.1533-1538
• Main Authors: LI, LI-PING, WU, WEI-JING, SUN, DA-YONG, XIE, ZI-YING, MA, YAN-CHUN, ZHAO, YA-GANG
• Format: Article
• Language: English
• Subjects: Apoptosis; Cancer; Cell cycle; Cell growth; cyclin-dependent kinase 6 protein; Disease prevention; Experiments; Gastric cancer; gastric carcinoma; Gene expression; Genetic aspects; Genetic research; Immunoglobulins; Kinases; Membranes; MGC-803; MicroRNA; microRNA-449; Oncology; Oncology, Experimental; Phosphotransferases; Properties; Proteins; real-time cell analysis; Stomach cancer; Studies; Tumors
• ISSN: 1792-1074; 1792-1082
• DOI: 10.3892/ol.2014.2370

The present study aimed to identify the association between microRNA (miR/miRNA)-449a, the cyclin-dependent kinase (CDK)6 protein and gastric carcinoma, and discuss the effect of miR-449a on the expression of the CDK6 protein. Quantitative (q)PCR and western blot analysis were used to analyze the expression of the miR-449a and the CDK6 protein in gastric carcinoma and tumor-adjacent normal tissues. The real-time cell analyzer and the DAPI staining test were used to monitor the different miR-449a levels regulating the proliferation and apoptosis of the MGC-803 cell line. Immunofluorescence and western blot analyses were used to detect the expression level of the CDK6 protein in the cells of the miR-449a upregulation and downregulation groups, and a control group. A scratch test was used to study the effects of miR-449a expression on migration and invasion. It was found that the expression of miR-449a was downregulated and the expression of CDK6 protein was upregulated in gastric carcinoma tissue. The level of MGC-803 cell proliferation was decreased and the apoptosis level was increased by the upregulation of miR-449a expression, and the opposite effect was shown by the downregulation of expression. The expression of the CDK6 protein in the MGC-803 cells was downregulated by upregulating the expression of miR-449a. The distance of the scratch was shortened markedly after 12 h by downregulating the expression of miR-449a in the MGC-803 cells. The present study identified that a lower expression level of miR-449 and a higher expression level of CDK6 may contribute to the occurrence and development of gastric cancer. Furthermore, it was shown that miR-449a is able to regulate the expression of the CDK6 protein.