PubMed | Nanyang Center Hospital Nanyang 473000 and Soochow University of China
Type: Journal Article | Journal: International journal of clinical and experimental pathology | Year: 2016
The aim is to discuss the relationship of Line-1 methylation and the MDR1 expression in esophageal squamous cell carcinoma (ESCC).We analyzed the methylation level of Line-1 by quantitative real-time MSP, and the expression of MDR1 by real-time RT-PCR in 310 ESCC and corresponding non-tumor tissues.We found that the methylation index (MI) of Line-1 decreased from 0.90 in non-tumor tissues toward 0.78 in ESCC. The cumulative survival was significantly shorter in ESCC patients with MI 0.78 (34 months) than that in patients with MI > 0.78 (43 months). There was a statistical difference between MI 0.78 and MI > 0.78 cases with these clinicopathologic parameters (age, AJCC stage, differentiation; P = 0.010, P < 0.0001, P = 0.015, respectively). These results implied that Line-1 hypomethylation could be more in ESCC patients with older, advanced tumor and poor differentiation group. Meanwhile, ESCC with demethylation of Line-1 were shown elevated MDR1 expression in tumor (Mean-Ct = 0.21), but ESCC with hypermethylation of Line-1 were considered to be decreased MDR1 expression in tumor (Mean-Ct = -0.86).Line-1 hypomethylation could be as a biomarker of poor prognosis in ESCC patients. MDR1 gene could be activated via epigenetic mechanisms with demethylation of Line-1 in ESCC, and enhance tumor progression.