Conclusion
While ZNF582 protein is highly expressed in cervical cancer tissues, it was not sufficient for use as a standard for cervical cancer staging. On the other hand, ZNF582 promoter methylation had high specificity and sensitivity in detecting CINII and highly diseased cervical lesions and could be used as a diagnostic marker for cervical cancer of women.
Methods
Tissue samples of normal cervical or chronic cervicitis (n=51), CIN (cervical intraepithelial neoplasia) (n=35), and cervical carcinoma (n=68) were tested for HPV16/18 infection by polymerase chain reaction (PCR). We also detected the methylation status of the ZNF582 gene promoter in the same tissues by methylation-specific PCR (MSP), then analyzed the correlation between ZNF582 promoter methylation and HPV16/18 infection. Immunohistochemistry was used to analyze ZNF582 gene expression in 152 cervical tissues. We detected ZNF582 mRNA expression in cervical tissues (including cancer and non-cancer) by real-time fluorescence quantitative PCR (qPCR).
Results
Among 93 high-grade cervical lesions (CINII and above) and cervical cancer samples, 57 cases were positive for HPV16/18 infection and 36 cases were negative. ZNF582 gene methylation occurred in 9 out of 51 cases in normal cervical tissues (17.6%), 16 of 35 cases in CIN tissues (45.7%), and 50 of 68 cases in cervical cancer (73.5%). The differences in methylation rate of the three groups were statistically significant (P<0.05). The ZNF582 methylation rate in the positive HPV16/18 infection group was 73.7%, while the negative group was 63.9%. Compared with normal tissues, ZNF582 protein was highly expressed in cervical cancer tissues, but mRNA expression was low.