A Single Talent Immunogenic Membrane Antigen and Novel Prognostic Predictor: voltage-dependent anion channel 1 (VDAC1) in Pancreatic Cancer

Immunogenic membrane antigens associated with multiple biological functions of human cancer cells, have significant value in molecule diagnosis and targeted therapy. Here we screened immunogenic membrane antigens in pancreatic cancer by immunobloting IgG purified from sera of 66 pancreatic cancer patients with membrane proteins separated from two-dimensional PAGE of human pancreatic cancer cell line SWl990, and identified voltage-dependent anion channel 1 (VDAC1) as one of the potential immunogenic membrane antigens. Further studies focusing on VDAC1 demonstrated that VDAC1 mRNA and protein were significantly expressed in the tested pancreatic cancer cell lines. VDAC1 silencing with RNAi significantly decreased cell growth, invasion and migration in the pancreatic cancer cell line Capan-1. Additionally, VDAC1 expression was upregulated in pancreatic cancer tissue compared with normal pancreas samples and patients with low VDAC1 expression had a significantly greater median survival compared to those with high expression (27.0 months vs. 17.8 months, P = 0.039). In multivariable analysis, VDAC1 staining was an independent prognostic factor for survival [(Hazard-Ratio) HR = 1.544, 95% CI = 0.794-3.0, P = 0.021]. These results demonstrated that VDAC1 may be a candidate immunogenic membrane antigen for pancreatic cancer, a potential independent prognostic marker, and an ideal drug target.