galectin-9 expression profile in patients with gastric cancer and peptic ulcer disease

Background: chronic inflammation and dysregulation of the immune system mechanisms are now well established as primary triggers to gastric cancer and peptic ulcer disease. galectin-9 (gal-9) is a member of the galectin family and known as an inducer of cell aggregation, adhesion and apoptosis. gal-9 interaction with its main ligand t-cell immunoglobulin and mucin domain protein-3 (tim-3) leads to the apoptosis of t cells and dys-regulation of the immune responses in different tumors. in the current study, the mrna expression pattern of gal-9 was evaluated in gastric biopsies of patients with gastric cancer and peptic ulcer disease. materials and methods: in this case control study, gastric biopsies were obtained from 46 patients with gastric cancer, 44 patients with peptic ulcer disease and 41 cases with non-ulcer dyspepsia served as controls who underwent endoscopy for the evaluation of their gastric problems. infection with helicobacter pylori was determined by rapid urease test for all participants and h&e staining for gc patients. total rna was extracted from all gastric tissues and used for cdna synthesis. relative expression of gal-9 mrna was determined by real-time pcr using β-actin as a housekeeping gene. results: gal-9 was similarly expressed in all three studied groups. no statistical difference was found for gal-9 expression between gastric cancer patients and control group (2-δct =0.022 vs 0.0144, p=0.30) and also between peptic ulcer and control groups (2-δct =0.088 vs 0.144, p=0.16). no correlation was found between gal-9 expression and infection with helicobacter pylori (2-δct = 0.1 vs 0.129, p=0.51). conclusion: similar expression of gal-9 in gastric tissues from patients with gastric cancer, peptic ulcer and also non-ulcer dyspepsia individuals suggests no possible role of this molecule on tumorigenesis and immunoregulatory mechanisms of these gastric disorders.