Correlation between PIK3CA，PTEN and p16 Protein Expression and Human Papillomavirus Infection in Different Cervical Tissues

Objective To evaluate correlations between PIK3CA，PTEN and p16 protein expression，and human papillomavirus (HPV) infection in the normal cervix epithelium，cervical intraepithelial neoplasia (CIN) and cervix squamous cell carcinoma (SCC). Methods The immunohistochemical staining PV-9000 method was used to detect the expression of PIK3CA，PTEN and p16 protein and high-risk HPV16/18 infection was detected by chromogenic in situ Hybridization in 30 cases of SCC (SCC group) ，21 cases of CIN Ⅰ(CINⅠgroup)，51 cases of CINⅡ～Ⅲ(CIN Ⅱ～Ⅲ group)，and 22 cases of normal cervix tissues (control group). Results PIK3CA and p16 protein expression rate and HPV16/18 infection rate were gradually increased，but PTEN protein expression rate was gradually decreased along with the malignant transformation of cervical epithelium.The differences of PIK3CA，PTEN，p16 protein and HPV16/18 prevalence in cervical cancer and CIN Ⅱ ~ Ⅲ group were significant，compared with control group or CIN Ⅰ group，(P<0.05).In cervical intraepithelial neoplasia tissues，PIK3CA positive rate (76.47%，39 cases) in CIN Ⅱ ~ Ⅲwas significant higher than that in CIN Ⅰ(42.86% ，9 cases)，P=0.006.PTEN and p16 protein positive rates were similar in different CIN groups.In 81 cases of human CIN Ⅱ ~ Ⅲ and squamous cell carcinoma，PIK3CA showed a significant positive correlation to p16 protein (P=0.000，r=0.544).PIK3CA，p16 protein were negative correlated to PTEN protein expression (P<0.05).In 47 HPV16/18 positive specimens，PIK3CA，and p16 protein expressions almost were positive correlation (P<0.01)，but 37 cases of PTEN protein expression were negative，(P=0.116). Conclusion PIK3CA，PTEN，p16 protein expression and high-risk HPV infection were closely related to the development of cervical cancer.Combined detection of PIK3CA，PTEN，p16 protein and high-risk HPV might be a molecular marker for SCC early diagnosis.The over-expressions of PIK3CA and p16 protein were related with high-risk human papillomavirus infection.