Abstract: Background and purpose: In recent years, epigenetics research has become a new direction of cancer research. A large number of results have shown that the abnormal changes of epigenetic modifications have close connection with cancer. Genome-wide epigenetic modifications have become new markers for cancer. This study aimed to investigate the methylation of the promoter of DBC1 gene in cervical cancer tissues of Uyghur women in Xinjiang, to explore the correlation between the gene methylation and the infection of HPV, and to evaluate whether it can be used as a tool with high sensitivity and specificity for cervical cancer screening. Methods: This study detected the infection of HPV16, 18 in 43 normal cervical tissues, 35 cervical intraepithelial neoplasia tissues and 54 cervical cancer tissues using the polymerase chain reaction (PCR) method. The methylation of the promoter of DBC1 gene in above-mentioned tissues was detected by the methylation-specific PCR method. The expression of DBC1 at mRNA level was measured by real-time fluorescent quantitative polymerase chain reaction (RTFQ-PCR) in 10 methylation-negative normal cervical tissues and 10 methylation-positive cervical cancer tissues. Results: In normal cervical tissues, CIN tissues and cervical cancer tissues, the infection ratios of HPV16 were 18.6%, 34.3% and 68.5%, respectively; the infection ratios of HPV18 were 2.3%, 8.6% and 16.7%, respectively; and the methylation ratios of DBC1 gene were 23.3%, 40.0%, 87.0%, respectively. In 79 highgrade squamous intraepithelial lesions (CINⅡ and Ⅲ) and cervical cancer tissues, 50 of 79 were infected with HPV16/18, while 29 of 79 were negative. The methylation ratio of DBC1 gene was 88.0% in HPV16/18 infection positive group while the methylation ratio was 55.2% in negative group (P<0.05). The expression of DBC1 gene at mRNA level in 10 methylation-positive cervical cancer tissues was significantly lower than that in the 10 methylation-negative normal cervical tissues (P<0.05). Conclusion: The methylation of DBC1 gene may become a molecular marker to detect cervical cancer of Uyghur women in Xinjiang. DBC1 gene methylation combined with HPV16/18 infection test can be used to aid diagnosis of cervical cancer.

Key words: Cervical cancer, DBC1 gene methylation, HPV16/18, Gene expression