The Expression And Regulation Of MiRNA-34a In Cervical Cancer

Objective：To analysis the expressions of miR-34a,P53and CDK4in CINIII,cervical cancerand normal cervical tissue,so as to explore the molecular mechanisms of cervicalcancer,and try to find new indicators for early diagnosis and new treatment targets ofcervical cancer.Methods：Fresh normal cervical tissue,CINIII and cervical tissue specimens were collected（The samples diagnosed by pathological examinations were obtained from patientsin the First Affiliated Hospital of Nanchang University. All of the patients did notreceive any chemotherapy, radiotherapy or immunotherapy.）Specimens were dividedinto three groups:CINIII;cervical cancer(underwent radical hysterectomy and pelviclymph node dissection) and control group（normal cervical tissue obtained frompatients who received hysterectomy because of Uterine fibroid.）Specimens werefrozen at-80°C ultra-low temperature freezer. The expression of P53was detectedby Immunohistochemistry. Real-time PCR was employed to analysis the expressionof miR-34a. The expression of CDK4which was targeted by miR-34a was detectedby Western blot.Result:1. The expression of P53in CINIII,cervical cancer and normal cervical tissuewas detected by Immunohistochemistry. The results showed that the positive rates ofP53were0%（0/18）,35%（7/20）,68%（34/50）respectively in normal cervicaltissue,CINIII and cervical cancer. Compared with the normal cervical tissue, thepositive rates of P53in CINIII and cervical cancer were much higher（P<0.01).Meanwhile the positive rate of P53in cervical cancer was higher than that in CINIII（P<0.05）.2. Real-time PCR was employed to analysis the expression of miR-34a. Therelative expression levels of miR-34a in CINIII and cervical cancer were significantly lower than that in normal cervical tissue（P<0.01). Compared with CINIII,theexpression of miR-34a decreased a lot in cervical cancer（P<0.01).3. The expression of CDK4was detected by Western blot. The results suggestedthat the expression of CDK4revealed an upward trend with the increasing severity ofcervical cancer. The gray ratios of CDK4/β-actin in normal cervical tissue,CINIII andcervical cancer were0.18±0.01,0.31±0.02and0.64±0.04respectively. The expressionof CDK4in CINIII and cervical cancer was significantly higher than that in controlgroup（P<0.01). At the same time the difference of the expression of CDK4betweenCINIII and cervical cancer was significant（P<0.01).Conclusion:With the progression of cervical lesions, the positive rate of P53increasedgradually. Meanwhile,downregulation of miR-34a and upregulation of CDK4couldbe found during the whole process. The results suggested that all these three factorswere involved in the process of the development of cervical cancer.