LINC02418 suppresses endometrial cancer progression via regulating miR-494-3p/RASGRF1 axis.

Long non-coding RNAs (lncRNAs) have emerged as pivotal regulatory molecules in cancer biology. Among these, long intergenic non-protein coding RNA 02418 (LINC02418), a recently identified lncRNA, has been linked to endometrial cancer (EC), although its function and operational mechanisms are largely unclear. The present investigation aims to elucidate the molecular mechanism through which LINC02418 influences EC pathogenesis. We employed Western blotting and quantitative real-time PCR to analyze Ras protein specific guanine nucleotide releasing factor 1 (RASGRF1) and LINC02418 expression profiles in EC tissues and cell lines. Functional analyses, including cell proliferation, migration, and invasion assays, were conducted to evaluate the impact of LINC02418 overexpression on EC cells. Xenograft mouse models were established for in vivo validation. The molecular interactions between LINC02418, miR-494-3p, and RASGRF1 were characterized using luciferase reporter and RNA pull-down assays. LINC02418 expression was significantly downregulated in EC tissues and cell lines compared to their normal counterparts. Forced expression of LINC02418 significantly suppressed EC cell proliferation, migration, and invasion in vitro. In xenograft models, LINC02418 overexpression resulted in reduced tumor burden and enhanced cell death. Mechanistically, LINC02418 enhanced RASGRF1 expression by sequestering miR-494-3p, a finding substantiated by RNA pull-down assays. The tumor-suppressive effects of LINC02418 were partially reversed by RASGRF1 silencing and miR-494-3p overexpression. Clinical analyses revealed that reduced RASGRF1 expression correlated with poor histological differentiation, advanced tumor stages, and decreased overall survival in EC patients. Our findings establish LINC02418 as a tumor suppressor that regulates EC progression through modulation of the miR-494-3p/RASGRF1 axis, highlighting its potential as a therapeutic target in EC treatment.