Short tandem repeat polymorphism in exon 4 of esophageal cancer-related gene 2 detected in genomic DNA is a prognostic marker for esophageal cancer

Background Short tandem repeat (STR) polymorphisms in exon 4 of the esophageal cancer-related gene 2 (ECRG2) are a risk marker for esophageal carcinoma. The aim of the present study was to correlate these STRs with clinical outcome. Methods Genomic DNA of 86 patients who underwent complete surgical resection was analyzed for STRs TCA3/TCA3, TCA3/TCA4, and TCA4/TCA4 in exon 4 of ECRG2 by polymerase chain reaction and DNA sequencing. Results ECRG2 STR TCA3/TCA3 and TCA3/TCA4 were found in 40 (47%) patients, respectively, and TCA4/TCA4 in 6 (7%) cases. TCA3/TCA3 genotype was significantly associated with reduced survival (P < .05, log-rank test). TCA3/TCA3 STR was the strongest prognostic factor determined by multivariate Cox regression analysis. Conclusions Genetically fixed STR polymorphism TCA3/TCA3 in exon 4 of ECRG2 is associated with poor clinical outcome in surgically treated esophageal cancer patients and might be a potential prognostic marker. The usefulness of these genetic markers to predict responsiveness toward neoadjuvant treatment of esophageal cancer patients would be of high clinical interest and should be examined in future studies.