Background
Colon adenocarcinoma (COAD) is among the most common malignancies worldwide. Elucidating the function and mechanism of action of the lncRNA VPS9D1-AS1 in COAD will be of great value for identifying potential therapeutic targets.
Conclusion
This study identified a novel competing endogenous RNA (ceRNA) pathway that potentially associates with the oncogenic functions of VPS9D1-AS1, miR-324-5p, and ITGA2 in COAD, which could contribute to the identification of new therapeutic approaches targeting COAD.
Methods
Quantitative real-time polymerase chain reaction (qRT-PCR) analysis was used to measure the expression levels of lncRNA VPS9D1-AS1 in COAD tissues and cell lines. After knocking down the expression of VPS9D1-AS1 in two COAD cell lines, namely SW1116 and LoVo, their proliferation rate was measured by the 5-ethynyl-2'-deoxyuridine (Edu) incorporation and cell counting kit-8 (CCK-8) viability assays, migration and invasion abilities were assessed by wound healing and Transwell assays, and apoptosis rate was measured withflow cytometry. Additionally, the dual luciferase reporter assay system was used to investigate the targeting of miR-324-5p to VPS9D1-AS1 and ITGA2 3'-UTR. The inhibitory effects of the miR-324-5p/ITGA2 axis on the function of VPS9D1-AS1 were also examined. In vivo tumorigenesis assay was performed in nude mice injected with VPS9D1-AS1 shRNA or control shRNA lentivirus-transfected LoVo cells.
Results
VPS9D1-AS1 was found to be upregulated in COAD tissues and cell lines. VPS9D1-AS1 knockdown inhibited the COAD cell proliferation, migration and invasion and increased the apoptosis rate. In addition, we have demonstrated that miR-324-5p targets VPS9D1-AS1 and ITGA2 3'-UTR, and miR-324-5p silencing or forced ITGA2 expression attenuated the effect of VPS9D1-AS1 knockdown.