No Expression of Human Leukocyte Antigen G (HLA-G) in Colorectal Cancer Cells
Kawin Leelawat MD, PhD*,**, Surang Engprasert PhD***, Urai Pongchai-rerk DVM*, Supatip Tuchinda MSc****, Cheepsumon Suthipintawong MD****, Vijittra Leardkamolkarn PhD*
Affiliation : * Department of Anatomy, Faculty of Science, Mahidol University ** Department of Surgery, Rajavithi Hospital *** Department of Pharmacognosy, Faculty of Pharmaceutical Science, Kyushu University, Japan **** Department of Pathology, Rajavithi Hospital
Although there is a specific antitumor immune response in the body, colorectal cancer cells progressively develop. This fact indicated that the cancer cells could have a variety of mechanisms to evade or escape the immune system. HLA-G is identified to inhibit the recognition of NK-cell in various kinds of cancers. This study investigated the expression of HLA-G in colorectal cancer. Eighty five specimens of colorectal cancer, carcinoma in situ and adenomatous polyp were examined by immunohistochemistry and RT-PCR for the detection of human leukocyte antigen (HLA)-G. The expression of HLA-G was not found in all colorectal specimens (85/85) both protein level and transcription level, suggesting that the expression of HLA-G is not a possible immune evasion mechanism of colorectal cancer cell.
Keywords : Immune evasion, Colorectal cancer, Adenomatous polyp, HLA-G
