Association between promoter methylation and expression of thyroid hormone receptor beta (THR beta) gene in patients with gastric cancer in an Iranian population

Abstract

Background and AimThere is evidence that gastric cancer patients suffer from thyroid disorders. However, the relationship between thyroid receptor (TR) expression and gastric cancer remains unknown. The aim of this study was to evaluate the status of promoter methylation and expression of the thyroid hormone receptor beta (THR) gene in gastric cancer patients in an Iranian population. MethodsAnalysis of THR promoter methylation was performed on 85 pairs of formalin-fixed, paraffin-embedded (FFPE) tissue samples as cases and controls via methylation-specific polymerase chain reaction (PCR MSP). The samples were obtained from tumors and surrounding healthy tissues from resected gastric cancers. The expression assay was also performed with 25 FFPE tissue pairs (tumor and surrounding healthy tissues of the same individual) using real-time PCR. ResultsThe results of the present study show that there is a statistically significant difference between tumor and adjacent normal tissues regarding promoter methylation status and THR expression (P=0.04 and P=0.036, respectively). ConclusionTherefore, promoter methylation of THR may be involved in the development of gastric cancer.