The effects of LINC00665 targeting miR-34a-5p on the proliferation, migration and invasion of esophageal cancer cells

Objective  To investigate the effects of LINC00665 targeting and regulating micrornas(miR) 34a-5p on the proliferation, migration and invasion of esophageal cancer cells.

Methods  The cancer tissues and adjacent tissues of patients with esophageal cancer were collected, the expression levels of LINC00665 and miR-34a-5p in tissues were detected by qRT-PCR.The esophageal cancer cell line EC9706 were divided into the control group, negative transfection(siNC) group, LINC00665 small interfering RNA vector(siLINC00665) group, siLINC00665+inhibitor negative transfection(anti-NC) group and siLINC00665+miR-34a-5p inhibitor(anti-miR-34a-5p) group.The proliferation ability of cells was detected by CCK-8 method, the numbers of cell invasion and migration were detected by Transwell assay; the protein expression levels of matrix metalloproteinase 2(MMP-2), cyclin D1(CyclinD1) and p21 were measured by Western blotting, and the targeting relationship between LINC00665 and miR-34a-5p was verified by dual-luciferase experiment.

Results  The expression level of LINC00665 in cancer tissues of patients with esophageal cancer was obviously higher than that in adjacent tissues, and the expression level of miR-34a-5p in cancer tissues was obviously lower (P < 0.01).Compared with the control group and siNC group, the OD value(24, 48 h), numbers of invasion and migration, expression levels of CyclinD1, MMP-2 proteins and LINC00665 in siLINC00665 group were obviously lower, and the expression levels of p21 protein and miR-34a-5p was obviously higher (P < 0.05).Compared with the siLINC00665+anti-NC group, the OD value (24, 48 h), numbers of invasion and migration, expression levels of CyclinD1, MMP-2 proteins and LINC00665 in siLINC00665+anti-miR-34a-5p group were obviously higher, and the expression levels of p21 protein and miR-34a-5p were obviously lower (P < 0.05).The targeting relationship between LINC00665 and miR-34a-5p was confirmed by dual-luciferase reporter gene experiment.

Conclusions  Silencing LINC00665 can target and up-regulate the expression of miR-34a-5p, thereby inhibiting the proliferation, migration and invasion of esophageal cancer cells.