Relationship between excision repair cross-complementation group 1 methylation and sensitivity to cisplatin-based concurrent chemoradiotherapy in cervical squamous cell carcinoma

Abstract

Objective To investigate the correlation of the excision repair cross-complementation group 1(ERCC1) gene methylation status with sensitivity to cisplatin-based concurrent chemoradiotherapy and clinical pathological characteristics in patients with cervical squamous cell carcinoma (CSCC). Methods Methylation specific polymerase chain reaction was used to determine the ERCC1 gene methylation status in cervical tissue from 20 healthy people and 60 patients with CSCC. All patients with CSCC were treated with cisplatin-based concurrent chemoradiotherapy. The treatment outcomes were evaluated using the Response Evaluation Criteria in Solid Tumors. Based on the treatment outcomes, patients with a complete response were assigned to chemoradiotherapy-sensitive group, and patients with a partial response, stable disease, or progressive disease were assigned to chemoradiotherapy-resistant group. Comparison of the ERCC1 gene methylation status between the two groups was made by χ2 test, and multivariate logistic regression analysis was used to analyze the relationship of the ERCC1 gene methylation status with various clinical pathological characteristics and sensitivity to chemoradiotherapy. Results The ERCC1 gene methylation rate was significantly higher in cervical tissue with CSCC than in normal cervical tissue (60% vs. 0%, P=0.000). The multivariate analysis showed that ERCC1 gene methylation was an independent influencing factor for sensitivity to cisplatin-based concurrent chemoradiotherapy in CSCC (P=0.022); ERCC1 gene methylation was significantly correlated with histological grade of CSCC (P=0.030); there was no significant relationship of ERCC1 gene methylation with clinical pathological characteristics including age, tumor size, lymph node metastasis, FIGO stage, and pretreatment hemoglobin and platelet count (P=0.729, 0.707, 0.340, 0.747, 0.073, 1.000). Conclusions The ERCC1 gene promoter methylation status may be involved in the development and progression of CSCC. It may also influence the sensitivity of patients with CSCC to cisplatin-based concurrent chemoradiotherapy by playing a role in cell differentiation. Key words: Excision repair cross-complementation group 1; Radiosensitivity; Cervical neoplasms/radiotherapy; Cervical neoplasms/chemotherapy