Fas ligand expression in colon cancer： A possible mechanism of tumor immune privilege

• Published in: World journal of gastroenterology : WJG 2005-06, Vol.11 (23), p.3632-3635
• Main Authors: Zhang, Wei, Ding, Er-Xun, Wang, Qiang, Zhu, Da-Qiao, He, Jin, Li, Yu-Li, Wang, Yuan-He
• Format: Article
• Language: English
• Subjects: Apoptosis - immunology; Brief Reports; Cell Line, Tumor; Colonic Neoplasms - immunology; Colonic Neoplasms - pathology; Fas Ligand Protein; Humans; Immunohistochemistry; Intestinal Mucosa - immunology; Intestinal Mucosa - pathology; Jurkat Cells; Membrane Glycoproteins - metabolism; T-Lymphocytes - cytology; T-Lymphocytes - immunology; T-Lymphocytes - pathology; 基因表达; 病理机制; 结肠肿瘤; 肿瘤免疫学
• ISSN: 1007-9327; 2219-2840
• DOI: 10.3748/wjg.v11.i23.3632

AIM: To detect the expression of Fas ligand (FasL) in colon cancer tissues and cell lines and analyze the function of FasL-expressing colon cancer cells in inducing Fas-sensitive T lymphocyte apoptosis. METHODS: Ninety surgically resected colon cancer tissues and 15 hepatic metastasis specimens were investigated by immunohistochemical method with normal colon mucosa and colon adenoma as control. The relationship between Fasl expression and pathologic features was also analyzed. Fasl expression of 4 colon cancer cell lines, SW620, Lovo, LS-174T and SW1116, were detected by Western blotting assay. The function of Fasl expressed on colon cancer cells was determined by coculture assay with Jurkat T lymphocytes, the apoptotic rate of which was detected by flow cytometry assay.RESULTS: Fifty-six (62.22%) cases of all the 90 coloncancer tissues and all (100%) the liver metastasis specimensexpressed FasL, significantly higher than normal colonmucosa and colonic adenoma. Higher expression of FasLwas found in more advanced stage of colon cancer andin cancer tissues with lymphatic or hepatic metastasis.All the colon cancer cell lines were found to express FasL.After coculture with the SW1116 cells for 24 h with aneffector: target ratio 10:1, the rate of apoptosis of Jurkatcells rose from 1.9% to 21.0%.CONCLUSION: The expression of FasL is upregulated incolon cancer and the functionally expressed FasL caninduce apoptosis of Fas-expressing T lymphocytes.