[Death-associated protein kinase promoter (DAPK) hypermethylation in uterine cervical cancer and intraepithelial neoplasia in Uyghur nationality women].

OBJECTIVE: To investigate the methylation levels of death-associated protein kinase (DAPK) in Uyghur female patients with different cervical lesions in Xinjiang, and to discuss the relationship of the expression and significance of DAPK in normal cervix, chronic cervicitis, cervical intraepithelial neoplasia (CINI, CIN II/III) and invasive cervical squamous cell carcinoma. METHODS: 30 cases of normal cervix and chronic cervicitis, 30 cases of CINI, 30 cases of CINII/III and 30 cases of cervical squamous cell carcinoma were tested by methylation specific PCR (MSP). Expressions of DAPK in 30 cases of normal cervix and chronic cervicitis, 30 cases of CINI, 30 cases of CINII/III and 30 cases of cervical squamous cell carcinoma were assayed using immunohistochemical SP staining. RESULTS: The methylation rate of DAPK gene in normal cervix and chronic cervicitis was 3.33%, 10% in cervical intraepithelial neoplasia CINI, 36.7% in CINII/III, and 63.3% in invasive cervical squamous cell carcinoma. The methylation rate of DAPK in the SCC group was significantly higher than that in the other groups (P < 0.05). Aberrant promoter methylation of the DAPK gene was positively correlated with the degree of cervical lesions. The positive rate of DAPK protein in normal cervix and chronic cervicitis was 93.3%, 83.3% in cervical intraepithelial neoplasia CINI, 60.0% in CINII/III, and 33.3% in invasive cervical squamous cell carcinoma. The expression of DAPK in the SCC group was significantly lower than that in the other groups (P < 0.05). The positive rate of DAPK protein was negatively correlated with the degree of cervical lesions (r(s) = -0.603, P < 0.001). CONCLUSIONS: Methylation of DAPK is involved in the cervical carcinogenesis and DAPK gene promoter methylation occurs in the early development of cervical cancer in Uyghur women in Xinjiang. Detection of DAPK gene methylation may provide a basis for use in early detection of cervical cancer. DAPK protein expression is decreasing even disappears along with the progression of cervical lesions.