Mechanisms Of Long Non-coding RNA Lnc-MX1-1 In Promoting Cellular Proliferation,Invasiveness And Metastasis In Prostate Cancer

Objective:This research aims to profile the IncRNAs expression patterns and screen differential expressed lncRNAs between prostate cancer(PCa)tissues and adj acent normal prostate tissues.Further,the effects of incRNA Inc-MXI-1 which over-expressed in prostate cancer tissues on proliferation and invasiveness of prostate cancer cells were examined.Additionally,the underlying molecular mechanisms of the biological functions of lnc-MXl-1 were explored.Methods:1.PCa and the paired adjacent normal prostate tissue samples were obtained for differential expressed IncRNAs profiling by using gene expression arrays.After screening,lnc-MXl-1,which highly expressed in prostate cancer tissues,was selected for further investigations.Gene array results of lnc-MX1-1 expression were confirmed by using real-time quantitative polymerase chain reaction(qRT-PCR)and RNA fluorescence in situ hybridization(RNA FISH)in prostate tissues and cell lines.2.To inhibit lnc-MX1-1 expression in prostate cancer cells,we designed small mterfering RNA(siRNA)and short hairpin RNA(shRNA)targeting lnc-MX1-1 for knockdown of its expression.CCK-8 cell proliferation experiments,clone formation experiments and nude mice PCa cells subcutaneous inoculation were carried out for examine proliferation and tumor formation ability of PCa cells after knockdown of lnc-MX1-1;Matrigel invasion experiments and nude mice PCa cells in situ inoculation were Carried out for examine invasiveness and metastasis of PCa cells after knockdown of lnc-MX1-1.3.Lentivirus overexpression vector construction and infection was performed to enhance lnc-MX1-1 expression in PCa cells.Gene expression arrays and miRNA arrays were used for profiling differential genes and miRNAs respectively after overexpression of lnc-MX1-1.Results:1.A variety of differential expressed IncRNAs between PCa tissues and the adjacent normal tissues were found.Among these IncRNAs,we noticed that lnc-MX1-1 was highly expressed in PCa tissues compared to either normal prostate transition zone(TZ)tissues or peripheral zone(PZ)tissues.QRT-PCR and RNA FISH analyses further confirmed the overexpression of Inc-MX1-1 in both P Ca tissues and PCa cell lines.2.Suppression of Inc-MX1-1 in LNCaP and 22Rvl cell lines were efficiently established by infection of shRNA expression lentivirus.Cells proliferation and invasion assesses indicate that the in vivo and vitro proliferation and invasiveness of PCa cells were significantly decre’ased after knockdown of lnc-MXl-1.3.Overexpression of lnc-MXl-1 in VCaP cells were carried out by lnc-MXl-1 overexpression lentivirus infection.Hereafter,gene expression array profiling and bioinformatics analyses suggested that lnc-MXl-1 might involve in regulating important cell signaling pathways and genes transcription.MiRNA array profiling also indicated several cancer associated miRNAs expression up-regulation and down-regulation induced by lnc-MX1-1 overexpression.Conclusion;Taken together,the present study shows that differential expressed lncRNAs exist b etween PCa tissues and their adjacent normal prostate tissues.More importantly,our study shows for the first time that overexpression of lnc-MX1-1 in PCa is involved in the disease progression.Additionally,the function of lnc-MX1-1 in promoting PCa cells proliferation and invasivene.ss might relate to the regulation of Inc-MX1-1 on cancerous signaling pathways or genes transcription.This mechanisms may induced by interaction between InG-MX1-1 and miRNAs,Our investigation of lnc-MX1-1 expression and exploration of lnc-MX1-1 functions enlighten the new PCa therapies by targeting the cancer promoting IncRNAs.