MiR-31 Is Aberrantly Expressed In Plasma Of Cervical Cancer And Its Effect On Cervical Cancer Cell Function

Cervical cancer is the most common malignant tumor in female genital tract, the second highest mortality rate in females worldwide. Persistent infection with high-risk types of human papillomavirus (HPV) is the basic factor for the development of cervical cancer. However, HPV infection alone is not enough to induce cervical cancer, other factors also play an important role, such as genetics and immunology.MicroRNA(miRNA) is a kind of endogenous non-coding small RNA molecules, which mainly regulates the expression of downstream target genes by combining with target mRNA specifically. MiR-31 has been confirmed to be abnormal expression in different tumor and involved in cell proliferation, differentiation and other biological processes. Besides, miRNA can induce the development of many diseases,especially the tumor.Recent studies have demonstrated that miR-31 is abnormal expressed in different tumors and involved in cell proliferation, apoptosis, cell invasion and migration. In our previous research, we have found that the overexpression of miR-31 in cervical tissue, but the expression of miR-31 in plasma of cervical cancer has not been reported.In this study, we have measured the expression of miR-31 in plasma of cervical cancer patients, and analyzed the relationship between the level of miR-31and clinical pathology features of cervical cancer patients, further investigated the influence of miR-31 on the proliferation and migration of Hela cells.PartⅠThe relationship between the expression of miR-31 in plasma and clinicopathology features of cervical cancerOBSTRACTIVE To investigate the expression of miR-31 in plasma of cervical cancer and the relationship between the level of miR-31 and clinicopathology features of cervical cancer.METHODES Collected the plasma of 60 samples cervical cancer patients before operation and the normal ones who were admitted in the Guangxi Zhuang Autonomous Region People’s Hospital from January 2013 to December 2015 Real-time PCR was used to detected the expression of miR-31 in plasma of cervical cancer patients analyzed the relationship between miR-31 level and clinical pathology features of cervical cancer patients.RESULTS The expression of miR-31 in plasma of cervical cancer was significantly higher than normal group (P<0.05). Our results showed that the expression level of miR-31 in plasma was significantly different in cases of the lymph node metastasis (LNM) and vessel invasion group(P<0.05). The expression level of miR-31 in cases of ⅡB2、the diameter>4cm、age≥50 and middle-high differentiation group were higher, but there was no significant difference (P>0.05).CONCLUSION MiR-31 was overexpressed in plasma of cervical cancer patients and the overexpression of miR-31 had relationship with the lymphatic metastasis, vascular invasion.Part ⅡThe construction of miR-31 lentiviral vector and the effect of miR-31 on cervical cancer cellsOBSTRACTIVE To construct the miR-31 lentiviral vector and investigate the influence of miR-31 on the biological function of cervical cells.METHODES PCR was used to amplify the target gene. Restriction endonuclease analysis and DNA sequencing have confirmed the sequence of the recombinant plasmid pCDH-miR-31.293T cells were co-transfected with the lentiviral vector pCDH-miR-31、pPACKH1-GAG. pPACKH1-REV and pVSV-G. The supernatant containing the lentivirus particles was harvested to determine the titer 3×107TU/ml. The Hela cells were infected with lentivirus, Puro was used to sort the Hela cells which stable overexpression miR-31. Real-time RT-PCR was used to detected the expression of miR-31 in Hela cells which stable overexpression miR-31. The cell proliferation was detected by clone formation assay and MTT assay, and the cell migration ability was detected by Transwell cell migration assay.RESULTS DNA sequencing demonstrated that insert sequence and miR-31 gene sequence matches were extremely close. The expression of miR-31 in Hela cells infected the lentiviral pCDH-miR-31 was significantly increased(P<0.05). Compared with the control group, the clone formation rates of Hela cells were increased in miR-31 overexpression group (P<0.05).MTT results showed that the proliferative effect of miR-31 on Hela was significant (P<0.05).The Transwell migration assays showed that overexpression of miR-31 enhance migration of Hela cells (P<0.05) 。CONCLUSION DNA sequencing demonstrated that the lentiviral vector pCDH-miR-31 was constructed successfully. MiR-31 can enhance the proliferation and the migration of Hela cells.