LncRNA DNAJC3-AS1 promotes gastric cancer malignancy through miR-576-5p-mediated upregulation of LYPLA1.

Long non-coding RNAs (lncRNAs) are involved in tumor progression, but the role of lnc-DNAJC3-AS1 in gastric cancer (GC) remains unclear. This study aimed to investigate the biological function and regulatory mechanism of lnc-DNAJC3-AS1 in GC. Reverse transcription quantitative PCR (RT-qPCR) was used to detect the expression levels of lnc-DNAJC3-AS1, miR-576-5p, and LYPLA1, and Western blot was used to analyze protein expression. The Cancer Genome Atlas (TCGA) database and clinical samples were used to evaluate their clinical relevance. Cell viability, cell cycle distribution, apoptosis, migration, and invasion were assessed using Cell Counting Kit-8 (CCK-8), flow cytometry, wound-healing, Transwell, and immunofluorescence assays. Dual-luciferase reporter assay, RNA immunoprecipitation (RIP), fluorescence in situ hybridization (FISH), and rescue assays were performed to explore the potential regulatory relationship among lnc-DNAJC3-AS1, miR-576-5p, and LYPLA1. A xenograft tumor model was also established to evaluate the role of lnc-DNAJC3-AS1 in vivo. The results showed that lnc-DNAJC3-AS1 and LYPLA1 were upregulated, whereas miR-576-5p was downregulated in GC tissues and cells. Knockdown of lnc-DNAJC3-AS1 inhibited GC cell viability, migration, and invasion, induced G0/G1 phase arrest and apoptosis, and suppressed tumor growth in vivo. Mechanistically, lnc-DNAJC3-AS1 was mainly localized in the cytoplasm and was associated with miR-576-5p-related RNA-induced silencing complex (RISC) complexes. MiR-576-5p targeted LYPLA1, and restoration of miR-576-5p or knockdown of LYPLA1 partially attenuated the effects of lnc-DNAJC3-AS1 overexpression on GC cell phenotypes and LYPLA1 enzymatic activity. These findings suggest that lnc-DNAJC3-AS1 promotes GC progression, at least in part, through the miR-576-5p/LYPLA1 pathway, providing a potential target for GC treatment.