Pyroptosis, a newly discovered form of programmed cell death, is involved in the occurrence, development and drug resistance of a variety of tumors and has attracted increasing attention in recent years. LINC00365 is a novel lncRNA that has rarely been reported before. We previously reported that LINC00365 expression in colorectal cancer is closely associated with poor patient outcomes. Additionally, LINC00365 was confirmed to be positively correlated with miR-221-5p, and miR-221-5p is negatively correlated with gasdermin-D (GSDMD) in colorectal cancer tissues. Bioinformatics analysis and luciferase reporter gene experiments revealed that GSDMD is the target gene of miR-221-5p. Cell function experiments and nude mouse tumor transplantation assays confirmed that LINC00365 could regulate the expressions of pyroptosis-related proteins such as Caspase-1, Caspase-11, NLRP3 and GSDMD. RNA pulldown and RNA immunoprecipitation experiments further elucidated the mechanism by which LINC00365 regulates miR-221-5p. In the present study, we observe that LINC00365 promotes the expression of miR-221-5p by binding to the Dicer enzyme to inhibit GSDMD and plays an antipyroptotic role. Our findings suggest that LINC00365 may serve as a molecular biomarker for estimating the prognosis of patients with colorectal cancer and as a potential therapeutic target for colorectal cancer.
Keywords: LINC00365; colorectal cancer; miR-221-5p; pyroptosis.