The Effect Of Abnormally Expressed MiRNAs And Their Target Genes On Cervical Cancer Cell Migration And Invasion And Its Molecular Mechanism In Cervical Cancer

Background: Cervical cancer is of the highest prevalence of female reproductive tract cancer,ranking the second place in the global female cancer death cause.Many factors contribute to cervical cancer,of which 80-90% of cervical cancers are caused by high-risk human papilloma virus(HR HPV)infection.Micro RNAs(miRNAs)are endogenous single-stranded small RNAs of about 22 nucleotides long that are widely expressed in eukaryotic cells.They do not encode proteins,but they present post-transcriptional regulation abilities.Although miRNAs and their regulatory genes play an important role in the invasion and metastasis of various tumors,their functions,especially miR-146b-3p’s and miR-134-3p’s function and mechaniasm in the invasion and metastasis of cervical cancer remains to be eluciadated.It is not clear whether HPV infection regulates the expression of these miRNAs either.Objective:(1)To identify target miRNAs that mediate the migration and invasion of cervical cancer cells of the 15-hydroxyprostaglandin dehydrogenase(HPGD)gene and explore the relationship between this miRNA and HPV E6/E7;(2)To identify the function of miR-134-3p and its target genes in cervical cancer,and to explore the relationship between this miRNA and its target genes and HPV E6/E7.Methods:(1)Bioinformatics analysis,luciferase reporter gene assay and western blot were used to identify the miRNAs that might regulate HPGD,which was found mediate cervical cancer cell migration and invasion in our previous study.Transwell migration and invasion assay was used to examine the function of the miRNA and explore the relationship between E6/E7 and miRNA.(2)A miRNA that is dysregulated in cervical cancer tissues was selected from miRNA microarrays and verified by using.Real-time quantitative polymerase chain reaction(RT-PCR)in cervical cancer tissues,followed by exploring its function in the migration and invasion of cervical cancer cells.By using bioinformatics prediction,luciferase reporter gene detection and western blot experiments,miRNA target gene was identified,followed by investigate its function in the invasion and invasion of cervical cancer cells by using Transwell migration and invasion assay.,The relationship between E6/E7 and miRNA and its target genes is then investigated.Results:(1)Luciferase reporter assay and western blot showed that miR-146b-3p could bind to HPGD CDS region;miRNA microarray and RT-q PCR validation showed that miR-146b-3p was highly expressed in cervical cancer;Phenotype assays showed that inhibition of miR-146b-3p could inhibit the migration and invasion of cervical cancer cell;and knocking down oncogene E6/E7 could inhibit the expression of miR-146b-3p.(2)miRNA microarray and RT-q PCR validation showed that inhibition of miR-134-3p in cervical cancer tissues;functional studies showed that overexpression of miR-134-3p could inhibit the migration and invasion of cervical cancer cells.Luciferase reporter assay and western blot results showed that miR-134-3p could bind to the 3’UTR of the Kelch domain containing 7B(KLHDC7B)gene.Functional experiments showed that KLHDC7 B knockdown could inhibit the migration and invasion of cervical cancer cells;knocking down tumorigenic gene E6/E7 could promote the expression of miR-134-3p and inhibit the expression of its target gene,KLHDC7 B.Conclusion:(1)HPV E6/E7 promotes the migration and invasion of cervical cancer cells by promoting miR-146b-3p mediated inhibition of HPGD;(2)HPV E6/E7 releases KLHDC7B to promote the migration and invasion of cervical cancer cells by inhibiting the expression of miR-134-3p.