[LncRNA LINC00342 regulates gastric cancer cell proliferation, migration and invasion by targeting miR-596].

OBJECTIVE: To investigate the expression levels of LINC00342 in gastric cancer (GC) tissues and cells and the pathways mediating its effects on biological behaviors of GC cells. METHODS: Bioinformatic analysis was performed to identify the lncRNAs and their downstream miRNAs involved in regulation of biological behaviors of GC cells. qRT-PCR was used to analyze the differential expression of LINC00342 and miR-596 in GC cell lines, human gastric mucosal cells, and GC and adjacent tissues. In human GC MGC-803 and MGC-823 cells, the effects of LINC00342 overexpression, miR-596 overexpression, LINC00342 knockdown, or miR-596 knockdown on cell proliferation, migration, invasion and cell cycle changes were examined using Edu assay, CCK-8 assay, wound healing assay, Transwell assay, and flow cytometry. The regulatory interaction between LINC00342 and miR-596 was investigated using a dual-luciferase reporter assay. RESULTS: Informatic analysis identified LINC00342 as the candidate lncRNA regulating biological behaviors of GC cells, with miR-596 as its downstream miRNA. LINC00342 expression levels were significantly higher while miR-596 expression levels were lower in GC tissues and cell lines than in the paired adjacent tissues and human gastric mucosal cell lines (all P<0.05). In MGC-803 and MGC-823 cells, overexpression of LINC00342 significantly enhanced cell proliferation (P<0.05), migration (P<0.01), and invasion (P<0.001) and reduced the percentage of G0/G1 phase cells (P<0.01), while knocking down LINC00342 significantly suppressed cell proliferation (P<0.05), migration (P<0.01), and invasion (P<0.001) and increased G0/G1 phase cell percentage (P<0.01). Modulation of miR-596 expression levels produced the opposite effects. Dual-luciferase reporter assay confirmed the specific binding between LINC00342 and miR-596 (P=0.0067). CONCLUSION: In GC cells, LINC00342 regulates cell proliferation, migration, and invasion by targeting miR-596.