Methylation of APC, TIMP3, and TERT: a new predictive marker to distinguish Barrett's oesophagus patients at risk for malignant transformation

Abstract

Barrett's associated oesophageal adenocarcinoma (EAC) is one of the most rapidly increasing malignancies in Western countries. Because of its poor prognosis, management of this disease through screening of Barrett's oesophagus (BE) patients and identification of those with a high risk of developing an adenocarcinoma seems a promising approach. Early molecular markers of malignant transformation might contribute to such screening approaches. Gene promoter methylation analysis was performed on normal, pre-neoplastic, and neoplastic lesions from BE patients. All lesions of interest were sampled by microdissection from formalin-fixed paraffin-embedded tissue sections. We found that, in 27 adenocarcinomas, APC, TIMP3, TERT, CDKN2A, and SFRP1 promoters were methylated in 93%, 65%, 64%, 48%, and 91%, respectively; in contrast MLH1, RASSF1, RARB, CDH1, and FHIT promoters were methylated in less than 5% of the tumours. In BE mucosa from patients who had progressed to adenocarcinoma (12 samples), APC, TIMP3, and TERT promoters were hypermethylated in 100%, 91%, and 92% of cases, whereas in BE mucosa from patients who had not progressed (16 samples) methylation was found only in 36%, 23%, and 17%, respectively. Furthermore, the epigenetic profile of BE with and without EAC differed significantly with, respectively, 81% and 26% of the PCR samples showing promoter hypermethylation for APC, TIMP3, and TERT (p < 0.0001). Promoter methylation of CDKN2A was infrequently detected in BE samples, while SFRP1 methylation was observed in all samples. Our results suggest that promoter methylation profiling of BE using multiple target genes including APC, TIMP3, and TERT might be used as a predictive marker for increased EAC risk.

Effects of Helicobacter pylori infection on genetic instability, the aberrant CpG island methylation status and the cellular phenotype in Barrett's esophagus in a Japanese population

“…50 In our results, p16 hypermethylation was certainly present in SIM in BE despite the fact that the methylation rate was slightly lower than the rates described in previously published reports. 44,49 On the other hand, the promoter methylation of APC was more frequently detected in Group BE than in Group CLE (p < 0.005).…”

Alterations of the Wnt signaling pathway during the neoplastic progression of Barrett's esophagus

“…All samples had been formalin-fixed and paraffin-embedded. Normal human placenta was used as a positive control for the RT-PCR analyses and human normal colon mucosa was used as positive control for the methylation analysis (Clement and Benhattar, 2005). The use of human tissues in this study was authorized by the local ethics committee.…”

“…Methylation-sensitive dot blot assay of the APC, SFRP1 and SFRP2 promoters An MS-DBA was performed for the APC, SFRP1 and SFRP2 gene promoters using two different commercially synthesized oligonucleotide probes specific for the amplified sequences, as previously described (Clement and Benhattar, 2005). …”

Evidence for Enhanced Telomerase Activity in Barrett's Esophagus with Dysplasia and Adenocarcinoma

“…Consequently, hTR is a less reliable method for determining telomerase activity and hence did not gain widespread acceptance. Studies have suggested that, in some cancers, human telomerase catalytic enzyme subunit (hTERT) mRNA expression is the main determinant of telomerase activity (Meyerson et al, 1997;Bodnar et al 1998;Nakayama et al, 1998;Going et al, 2004;Clement et al, 2006;Shammas et al, 2011), as expression of hTERT is restricted to cells with telomerase activity only (Avilion et al, 1996). Lord et al (2000) evaluated hTERT expression in 13 patients with Barrett's metaplasia, 7 with Barrett's dysplasia, and 14 with esophageal adenocarcinoma.…”