Dystroglycan is Associated with Tumor Progression and Patient Survival in Gastric Cancer

Previous reports had indicated that there was a possible correlation of dystroglycan (DG) with biological behavior of cancer cells and cancer patients' survival. However, the role of DG expression in gastric cancer was rarely studied. In this study, alpha-DG and beta-DG expression were determined by immunohistochemistry in specimens of primary cancer, metastatic lymph node, distal metastatic lesion, and their normal counterpart tissues in 20 gastric cancer patients. Correlations between alpha-DG and beta-DG expression and prognosis were retrospectively analyzed. Our results found that positive expression of alpha-DG in normal mucosa, paired primary tumor, metastatic lymph node and distal metastatic site was detected in 95%, 70%, 25%, and 5% specimens, individually. Regarding beta-DG,it was 70%, 55%, 10%, and 10%, individually. Patients who had lower alpha-DG expression in tumors than in normal counterparts showed poor survival (p = 0.002), whereas such a correlation was not found in the case of beta-DG (p = 0.079). Difference of alpha-DG between primary tumor and its normal counterparts was an independent prognostic factor in gastric cancer with distal metastasis. This study showed DG expression was gradually reduced during tumor progression. Different expression of alpha-DG, but not beta-DG, between primary tumor and normal specimen, correlated with patient survival, implicating a potential marker for gastric cancer prognosis.