The relationship between Methylation of MGMT gene promoter and chemosensitivity and prognosis of non-small cell lung cancer

Objective:To detect the methylation status of MGMT gene promoter in non-small cell lung cancer (NSCLC), and to analyze the relationship between methylation of MGMT gene promoter and the chemosensitivity and prognosis of adjuvant chemotherapy after NSCLC. Methods: Tumor tissues and adjacent non-tumor tissues of 92 patients with NSCLC who underwent surgery and adjuvant chemotherapy from January 2012 to June 2015 in the thoracic surgery department of our hospital were collected, methylation-specific PCR (MSP) was used to detect the methylation status of MGMT gene promoter in tissues, and the relationship between methylation of MGMT gene promoter and chemosensitivity, progression-free survival (PFS) and 3-year overall survival rate was analyzed.Results: The methylation rate of MGMT gene promoter in cancer tissue was 39.13％ (36/92) higher than that in non-cancer tissue 3.26％ (3/92) (P < 0.05); methylation of MGMT gene promoter was associated with TNM stage, lymph node metastasis and tumor differentiation (P < 0.05); the proportion of patients with recurrence, metastasis or death in methylation group was higher than that in non-methylation group (P < 0.05); PFS and 3-year overall survival rate in methylated group were lower than those in non-methylated group (P < 0.05); multivariate COX regression analysis showed that lymph node metastasis and promoter methylation of MGMT gene were independent risk factors for prognosis of NSCLC patients.Conclusion: MGMT gene promoter methylation is closely related to the chemosensitivity and prognosis of platinum-based adjuvant chemotherapy after NSCLC. It may be an important target to reverse the chemosensitivity of platinum-based chemotherapy and improve the prognosis of NSCLC.