Document Type: Original Article
Department of Immunology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
Organ Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
Department of Pathology, Shiraz University of Medical Sciences, Shiraz, Iran
Background: Human leukocyte antigen (HLA)-G is a nonclassical HLA class I molecule with modulatory effects on NK and T cells. Because HLA-G expression is frequently detected in different solid tumors, it may be involved in tumor immune evasion. Objective: This study was designed to elucidate the prognostic value of HLA-G in hepatocellular carcinoma (HCC) and pancreatic adenocarcinoma (PADC). The influence of hepatitis B virus (HBV) infection on HLA-G expression was also evaluated in patients with HCC. Methods: HLA-G expression was investigated in tumor tissues from patients with HCC (n=74) or PADC (n=42) with immunohistochemical techniques. The presence of HBV genome was also examined in HCC tumor tissues by PCR. Results: HLA-G expression was detected in 66% of PADC and in 31% of HCC samples. In contrast to HCC, HLA-G overexpression was associated with advanced stages and grades in PADC. HBV genome was detected in 31% of HCC samples but we found no correlation between HLA-G expression and the presence of HBV genome in these tumors. Conclusion: Our findings showed that HLA-G overexpression in tumor tissue correlated with poor prognosis in PADC. HLA-G expression is apparently affected by the patient’s genetic background and other epigenetic factors rather than by HBV infection.