Objective: To investigate the mechanism of LINC00518 affecting the proliferation, invasion, and migration of cutaneous malignant melanoma (CMM) cells via miR-526b-3p/EIF5A2 axis.
Methods: qRT-PCR was performed to measure the expression of LINC00518, miR-526b-3p, and EIF5A2 in CMM tissues from 40 patients. Si-LINC00518, pcDNA-LINC00518, miR-526b-3p mimic, miR-526b-3p inhibitor, si-EIF5A2, and their corresponding negative controls were transfected alone or co-transfected into CMM cells A375 and A2058. The expression of LINC00518, miR-526b-3p and EIF5A2 in A375 and A2058 cells was measured. Cell proliferation was tested by CCK-8 assay and EdU assay. Cell invasion and migration were detected by Transwell and scratch tests, respectively. The binding between LINC00518 and miR-526b-3p, and the binding between miR-526b-3p and EIF5A2 were verified by dual-luciferase reporter and RNA pull-down assays.
Results: LINC00518 and EIF5A2 were up-regulated and miR-526b-3p was down-regulated in CMM tissues and cells. CMM patients with highly expressed LINC00518 showed decreased survival time than those with lowly expressed LINC00518. Transfection of si-LINC00518, miR-526b-5p mimic or si-EIF5A2 weakened the proliferative, migratory, and invasive abilities of melanoma cells, while transfection of miR-526b-5p inhibitor or pcDNA-LINC00518 enhanced the progression of melanoma cells. Moreover, the proliferative, migratory, and invasive potentials of melanoma cells were decreased after co-transfection of si-EIF5A2 and pcDNA-LINC00518 compared with cells transfected with pcDNA-LINC00518 alone. LINC00518 bound to miR-526b-3p and miR-526b-3p targeted EIF5A2. LINC00518 negatively regulated miR-526b-3p expression but positively regulated EIF5A2. Furthermore, EIF5A2 expression was negatively associated with miR-526b-3p expression.
Conclusion: LINC00518 encourages CMM through the miR-526b-3p/EIF5A2 axis in terms of cell proliferation, invasion, and migration.