Abstract: Objective To investigate the role of piR⁃hsa⁃130912 on the proliferation, invasion and migration of epithelial ovarian cancer(EOC) cells  and its molecular mechanism. Methods BGISEQ UMI Small RNA sequencing and RT⁃qPCR were performed to identify piR⁃hsa⁃130912 in EOC tissues. LV⁃piR⁃hsa⁃130912⁃up, piR⁃hsa⁃130912⁃inhibitor and corresponding negative control virus were used to infect EOC cells A2780 and SKOV3 and interfere with the expression level of piR⁃hsa⁃130912. Cell proliferation was detected by CCK⁃8 and clone formation assays. Cells invasion and migration abilities were determined by Transwell assay and wound healing experiment. Western blot was used to examine the expression of tumor metastasis⁃related proteins zeb⁃1, E⁃cadherin and vimentin. The mechanism of piR⁃hsa⁃130912 regulating cell proliferation, invasion and migration was preliminarily explored by combining RNA sequencing, GSEA analysis, KEGG and GO analyses. Results BGISEQ UMI Small RNA sequencing and RT⁃qPCR results confirmed that piR⁃hsa⁃130912 was highly expressed in EOC tissues. Compared to the corresponding negative control group, overexpression of piR⁃hsa⁃130912 enhanced the proliferation, invasion and migration of A2780 and SKOV3 cells (all P<0.05), and promoted the protein expression of zeb⁃1 and vimentin in A2780 cells (P=0.020, 0.017), while inhibited the expression of E⁃cadherin (P<0.001). Additionally, inhibition of piR⁃hsa⁃130912 expression weakened the proliferation, invasion, and migration abilities of A2780 and SKOV3 cells (all P<0.05), and promoted the expression of E⁃cadherin in SKOV3 cells (P=0.005), while inhibited the expression of vimentin (P=0.015). Moreover, piR⁃hsa⁃130912 could be involved in the regulation of arachidonic acid metabolism, linoleic acid metabolism, MAPK signaling pathway and receptor tyrosine kinase. Conclusions piR⁃hsa⁃130912 could promote the proliferation, invasion and migration of EOC cells, and its mechanism may be related to the regulation of lipid metabolism, MAPK and other tumor⁃related signaling pathways.

Key words: Epithelial ovarian cancer, piRNA, Proliferation, Invasion, Migration