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.