Decreased expression of TRIM3 gene predicts a poor prognosis in gastric cancer.

BACKGROUND/AIMS Tripartite motif-containing 3 (TRIM3) is a member of the TRIM protein family which is known to be involved in development of numerous tumor types. However, the prognostic role of TRIM3 in gastric cancer (GC) remained to be clarified. The aim of this study was to evaluate the expression pattern and prognostic significance of TRIM3 gene and its relationship with β-catenin, CyclinD, and BCL2 expression in patients with GC. METHODS A total of 40 fresh primary gastric cancer tumors and their matched adjacent noncancerous tissues were selected from the First Affiliated Hospital of Mashhad University. Real-time quantitative RT-PCR was performed to evaluate differences in TRIM3 expression in GC and normal tissues. The correlation between TRIM3 expression level and patients' overall survival, some clinicopathological variables, and β-catenin, CyclinD, and BCL-2 genes expression level were also studied. Moreover, patients were divided in two groups according to the TRIM3 expression levels: low and high. RESULTS Compared to noncancerous tissues, TRIM3 expression in GC tissues was significantly increased (fold change = 1.58). Kaplan-Meier survival analysis revealed a significant difference of patient survival according to TRIM3 expression status (P = 0.012). Low TRIM3 expression was associated with shorter overall survival and was an independent predictor for poor prognosis in GC patients (HR, 1.25; 95%CI, 1.02-1.60; P = 0.045). Expression of TRIM3 was negatively correlated with expression of β-catenin, BCL-2, and CyclinD as genes for proliferation, apoptosis, and the cell cycle in GC patients. CONCLUSIONS This study demonstrates that decreased level of TRIM3 mRNA expression is associated with poor prognosis in patients with gastric cancer. TRIM3 may play a protective role in gastric cancer by relieving the effects of cancer progressive genes and could be considered for further investigations as a prognostic biomarker.