ABSTRACT
@#[Abstract] Objective: To investigate the effect of long non coding RNA (lncRNA) LINC00308 on proliferation, invasion and migration of prostate cancer cells and its related mechanism. Methods: lncRNAs and mRNAs differentially expressed in prostate cancer tissues and adjacent control tissues were screened by gene chip, and LINC00308 and TRIP13 (thyroid hormone receptor interactor13) were identified as the research objects. The effects of LINC00308 on the proliferation, invasion and migration of prostate cancer cells were detected by MTT assay, plate cloning, Transwell and scratch test. The above effects were verified in nude mice xenografts. The effect of LINC00308 on expression of TRIP13 in tumor tissues and cancer cells was detected by Western blotting and immunohistochemistry. Bioinformatics analysis, RIP (RNA immunoprecipitation), qPCR and Double luciferase gene reporter experiments were used to predict and explore the interaction mechanism between miR-361-5p and LINC00308 as well as TRIP13, and plate cloning and Transwell invasion test were used to verify the biological behaviors of cancer cells. Results: Both the microarray results and qPCR confirmed that the expressions of LINC00308 (P<0.01) and TRIP13 (P<0.05) were abnormally high in prostate cancer tissues and four cell lines; cell function test results showed that overexpression of LINC00308 could promote the proliferation, invasion and migration of prostate cancer PC3 cells (all P<0.05), while down-regulation of LINC00308 in prostate cancer cells had the opposite effect. In nude mice. LINC00308 could promote the tumorigenesis of prostate cancer cells in vivo, and increase the expression of TRIP13 both in vivo and in vitro (P<0.05). Bioinformatics analysis, RIP, qPCR and Double luciferase gene reporter results confirmed that miR-361-5p could bind to 3'-UTR of LINC00308 and TRIP13 respectively, and LINC00308 could act as a competing endogenous RNA (ceRNA) by sponging miR-361-5p to regulate the expression of TRIP13. In addition, MTT, plate cloning and Transwell assay confirmed the regulatory interaction among LINC00308 miR-361-5p and TRIP13 from the levels of proliferation, colony formation and invasion in cancer cells. Conclusion: LINC00308, which is abnormally highly expressed in prostate cancer tissues and cells, can inhibit the expression of miR-361-5p and enhance the expression of TRIP13 by exerting its ceRNA function, thus promoting the proliferation, invasion and migration of prostate cancer.