Overexpression Of MicroRNA-301a-3p Promotes Cell Invasion And Proliferation Through Targeting RUNX3 In Prostate Cancer

The abnormal expression of micro RNAs is associated with the process of tumorigenesis.Micro RNA-301a-3p(mi R-301a-3p)has been reported to be dysregulated and involved in the development of cancer in many human cancers.However,its role in prostate cancer is rarely reported.Elucidating the role and molecular mechanism of mi R-301a-3p in prostate cancer provides a potential therapeutic target for the treatment of prostate cancer.This thesis includes the following three parts:Part 1: The expression of mi R-301a-3p and RUNX3 in prostate cancer cells and tissues.Aims: The expression level of mi R-301a-3p and RUNX3 in prostate cancer cells and tissues.Methods: Specimens including 15 prostate cancer tissues and 15 paired paracancerous tissue specimens were colleced.Fluorescent quantitative PCR was usedto detect m RNA expression levels.Results: The expression of mi R-301a-3p was significantly up-regulated in prostate cancer and prostate cancer cell lines,and RUNX3 was significantly down-regulated.Part 2: The effect of mi R-301a-3p on the biological behavior of prostate cancer cells.Aims: The effect of mi R-301a-3p on the biological behavior of prostate cancer cells.Methods: MTT assay and clone formation assay were used to detect cell proliferation.Transwell was used to detectcell migration and invasion.The mi R-301a-3p mimics and anti-mi R-301a-3p were synthesized and transfected into prostate cancer cells to observe the effect of increasing or inhibiting the expression of mi R-301a-3p on the proliferation,migration,and invasion of prostate cancer cells.Results: Overexpression of mi R-301a-3p promoted proliferation of prostate cancer cells.Silencing expression of mi R-301a-3p inhibited proliferation of prostate cancer cells.Overexpression of mi R-301a-3p promoted cloning of human prostate cancer cells.Silencing mi R-301a-3p expression reduced the cloning of prostate cancer cells.Overexpression of mi R-301a-3p promoted invasion and metastasis of prostate cancer cells,and silencing of mi R-301a-3p inhibited prostate cancer cell invasion and metastasis.Part 3: Preliminary study on the mi R-301a-3p target gene and its cancer promotion mechanismAims: to study on the mi R-301a-3p target gene and its cancer promotion mechanismMethods: Construction of RUNX3 high expression plasmid was used to clarify the role of RUNX3 protein in mi R-301a-3p-induced biological function of prostate cancer cells.The RUNX3 3’UTR was mutated and the luciferase expression plasmid was used to investigate the effect of the 3’ UTR region on the regulation of RUNX3 expression by mi R-301a-3p.Western method was used for detecting protein expression levelsResults: mi R-301a-3p directly targeted RUNX3 gene.Overexpression of mi R-301a-3p significantly decreased RUNX3 protein expression in prostate cancer cells.Overexpression of mi R-301a-3p increases proliferation and invasion of prostate cancer cell and could be reversed by RUNX3 overexpression.Overexpression of mi R-301a-3p increased Wnt activity and increased the expression levels of c-myc and cyclin D1 which was the downstream of Wnt.Conversely,inhibition of mi R-301a-3p expression decreased Wnt activity and transcription levels of c-myc and cyclin D1.Overexpression of RUNX3 significantly inhibited the promotion of Wnt signaling pathway by mi R-301a-3pConclusion: mi R-301a-3p is significantly up-regulated in prostate cancer tissues and cancer cell lines and increases the tumorigenic potential of prostate cancer cells by downregulating the expression of RUNX3 mediating Wnt signaling pathway.We report the key role of mi R-301a-3p in prostate cancer and the direct relationship between mi R-301a-3p and RUNX3.Therefore,mi R-301a-3p promotes prostate cancer proliferation and invasion by targeting RUNX3,suggesting that it may serve as a potential therapeutic target for prostate cancer.