High-expression of V-domain Imuunoglobulin Suppressor of T-cell Activation (VISTA) Is Correlated with Advanced Pathological Features in Patients with Pancreatic Ductal Adenocarcinoma.

V-domain Imuunoglobulin suppressor of T-cell activation (VISTA) seems a promising immune checkpoint target in cancer treatment; however, its prognostic significance in pancreatic ductal adenocarcinoma (PDAC) remains unknown. Herein, 29 fresh PDAC tissue samples were used to evaluate the mRNA expression level of VISTA by real-time polymerase chain reaction (PCR). Besides, 40 formalin-fixed paraffin-embedded PDAC tissues were collected to evaluate VISTA protein expression by immunohistochemistry. Real-time PCR indicated that high expression of VISTA was significantly correlated with advanced stages of the cancer, based on the tumor/node/metastasis (TNM) stagingand tumor cell differentiation.  Immunohistochemistry results also showed significant correlation of the elevated cytoplasmic expression of VISTA with advanced TNM stages, older age of the patients and was a worsening indicator, regarding the disease-specific survival. In conclusion, we found that the expression levels of VISTA can be a potential prognostic biomarker in PDAC patients and its elevated levels are correlated with poor prognostic outcomes.