Farjadian Shirin, Tabebordbar Maryam, Mokhtari Maral, Safaei Akbar, Malekzadeh Mahyar, Ghaderi Abbas
Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran. Email:
Asian Pac J Cancer Prev. 2018 Oct 26;19(10):2731-2735. doi: 10.22034/APJCP.2018.19.10.2731.
Background: Overexpression of human leukocyte antigen G (HLA-G) and increased plasma levels of soluble HLA-G (sHLA-G) have been reported in different human malignancies, and are believed to be involved in tumor immune evasion. Objectives: This study was designed to evaluate the expression of HLA-G in tumor tissues and the plasma levels of sHLA-G in patients with gastrointestinal cancer, and to determine their associations with clinicopathological factors. The link between Helicobacter pylori infection and increased HLA-G expression or sHLA-G levels was also investigated in patients with gastric cancer. Methods: HLA-G expression was investigated in tumor tissues from 100 patients with gastric and colorectal adenocarcinoma using immunohistochemistry test, and plasma levels of sHLA-G were measured in 82 patients with ELISA method. The presence of H. pylori genome was investigated in tumor tissues from 25 patients with gastric cancer by PCR method. Results: HLA-G expression was observed in 43% of colorectal cancers and 34.6% of gastric cancers, and was not related with any of the clinicopathological factors. There was a significant correlation between increased sHLA-G level and stage I tumors. Eight of 25 (32%) gastric cancer specimens were positive for H. pylori, of which 3 samples were positive for HLA-G. Soluble HLA-G levels were above the cut-off value in all H. pylori-positive patients. Conclusion: Plasma levels of sHLA-G were significantly increased in our patients with a sensitivity of 89% and a specificity of 62%. Soluble HLA-G level can be considered a useful indicator for the early diagnosis of gastric and colorectal adenocarcinoma.
在不同的人类恶性肿瘤中，已报道人类白细胞抗原G（HLA - G）过表达以及可溶性HLA - G（sHLA - G）血浆水平升高，并且认为其与肿瘤免疫逃逸有关。目的：本研究旨在评估胃肠道癌患者肿瘤组织中HLA - G的表达及sHLA - G的血浆水平，并确定它们与临床病理因素的关联。还对胃癌患者中幽门螺杆菌感染与HLA - G表达增加或sHLA - G水平升高之间的联系进行了研究。方法：采用免疫组织化学检测法对100例胃和结肠腺癌患者的肿瘤组织进行HLA - G表达研究，采用酶联免疫吸附测定法对82例患者的血浆sHLA - G水平进行检测。通过聚合酶链反应法对25例胃癌患者的肿瘤组织进行幽门螺杆菌基因组检测。结果：在43%的结肠直肠癌和34.6%的胃癌中观察到HLA - G表达，且与任何临床病理因素均无关联。sHLA - G水平升高与I期肿瘤之间存在显著相关性。25例（32%）胃癌标本中有8例幽门螺杆菌呈阳性，其中3份样本HLA - G呈阳性。所有幽门螺杆菌阳性患者的可溶性HLA - G水平均高于临界值。结论：在我们的患者中，sHLA - G的血浆水平显著升高，敏感性为89%，特异性为62%。可溶性HLA - G水平可被视为胃和结肠腺癌早期诊断的有用指标。
