title: miR-449a and CDK6 in gastric carcinoma.
abstract: 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.
authors.affiliation: Department of Gastroenterology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, Guangdong 510010, P.R. China.
authors.forename: Li-Ping
authors.initials: LP
authors.lastname: Li
authors.affiliation: Department of Respiratory Medicine, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, Fujian 362000, P.R. China.
authors.forename: Wei-Jing
authors.initials: WJ
authors.lastname: Wu
authors.affiliation: Department of Gastroenterology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, Guangdong 510010, P.R. China.
authors.forename: DA-Yong
authors.initials: DY
authors.lastname: Sun
authors.affiliation: Department of Gastroenterology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, Guangdong 510010, P.R. China.
authors.forename: Zi-Ying
authors.initials: ZY
authors.lastname: Xie
authors.affiliation: Department of Gastroenterology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, Guangdong 510010, P.R. China.
authors.forename: Yan-Chun
authors.initials: YC
authors.lastname: Ma
authors.affiliation: Department of Gastroenterology, Guangzhou General Hospital of Guangzhou Military Command, Guangzhou, Guangdong 510010, P.R. China.
authors.forename: Ya-Gang
authors.initials: YG
authors.lastname: Zhao
keywords: MGC-803; cyclin-dependent kinase 6 protein; gastric carcinoma; microRNA-449; real-time cell analysis