The Inhibitory Effect Of Down-regulating LncRNA HOTAIR On Proliferation And Metastasis In Human Cervical Cancer Cells And Its Mechanism

Objective: Cervical cancer(CC)is one of the known common malignant tumors of the reproductive tract,which is mainly concentrated in women worldwidely.Although the screening and early diagnosis methods have improved in recent years,the high incidence and low postoperative survival are still unable to be solved.An overwhelming of long non-coding RNAs(Lnc RNAs),especially Lnc RNA HOTAIR,were involved in the occurrence and development of various kinds of tumors,and the abnormal expression in cervical cancer can be used as a biomarker for diagnosis and diagnosis.However,the mechanism of its role in cervical cancer is not clear.Methods: In this study,the levels of plasma and tissue EGFR,LncRNA HOTAIR and miR-34 a in 56 cases of patients with cervical cancer together with paired normal tussues and plasma were detected by RT-q PCR analysis,the clinical and pathological data,including the HPV16 and HPV18 content,age,tumor size,cancer type,FIGO stageaand differentiation degree were collected and correlation analysis was performed with EGFR,Lnc RNA HOTAIR and miR-34 a levels measured previously;moreover,7 cases of both high and low expression of Lnc RNA HOTAIR were followed up for the research of the survival rate in patients with cervical cancer;the primary cervical carcinoma and normal epithelial cells,human adenocarcinoma cells Si Ha,epithelioid cell He La and epidermal-like cells Caski and other cervical cell lines were utilized for the detection of EGFR,Lnc RNA HOTAIR and miR-34 a levels;then,a Lnc RNA HOTAIR silent model was established in primary cervical epithelial cells and H8 cell lines,primary cervical cancer epithelial cells and Hela cervical cancer cell lines followed by Lnc RNA HOTAIR si RNAs synthesis;and CCK-8 proliferation assay,DAPI staining,immunofluorescence,cell cycle and apoptosis detection with flow cytometry were performed in the studies of Lnc RNA HOTAIR on proliferation and apoptosis of cervical cancer cell;wound-healing assay together with Transwell cell migration and invasion assay,xenograft model in nude mice with Lnc RNA HOTAIR si RNAs and/or miR-34 a inhibitor treatment were performed in the studies of Lnc RNA HOTAIR on migration and invasion of cervical cancer cell;Western blot combined with RT-q PCR were performed for the study of the potential molecular mechanism.Results: Based on the analysis of LncRNA HOTAIR,miR-34 a and EGFR in pericarcinomatous,carcinomatous tissues and plasma of 56 cases of patients with cervical cancer tissues(also collected from 56 healthy volunteers plasma),combined with the results of clinical and pathological data,it has been showed the expression of Lnc RNA HOTAIR and EGFR in cervical cancer was significantly increased,accompanied with decreased miR-34 a.And Lnc RNA HOTAIR levels positively correlated with HPV16,HPV18 content,tumor volume,EGFR content,negatively correlated with miR-34a;furthermore,patients with high expression of Lnc RNA HOTAIR in cervical cancer had lower survival rates than that with low expression of Lnc RNA HOTAIR;high level of Lnc RNA HOTAIR was detected in primary carcinomatous epithelial cells and cervical cancer cell lines;Lnc RNA HOTAIR silencing can significantly inhibit proliferation of Hela cell in vitro and in vivo,and promote apoptosis in vitro;while miR-34 a was up-regulated and Wnt/b-catenin signaling pathway was inhibited.Furthermore,the silencing of Lnc RNA HOTAIR can inhibit the migration and invasion in vivo,even tumorigenesis of Hela cells in vitro,this effect can be antagonized by miR-34 a inhibitor and maybe related to the inhibition of c-Met signaling pathway,EGFR/JAK2/STAT3 signaling pathway and EMT activation.Conclusion: The expression of Lnc RNA HOTAIR in plasma may be used as biomarker for the prognosis and development monitoring of cervical cancer pathogenesis,even for the postoperative recovery evaluation;downregulation of Lnc RNA HOTAIR can significantly enhance the miR-34 a in cervical cancer epithelial cells and inhibit Wnt/b-catenin activation,results in cell cycle arrest and apoptosis mediated by Bcl2 in mitochondria and caspases activation.the down-regulation of Lnc RNA HOTAIR could significantly blocking cervical carcinoma cell migration,invasion and tumorigenicity in vivo through inhibit the c-Met signaling pathway,EGFR/JAK2/STAT3 signaling pathway and activation of EMT,which could be stopped by miR-34 a inhibitor.