Enjoji Munechika, Nakashima Manabu, Nishi Hidehiro, Choi Ilseung, Oimomi Hideki, Sugimoto Rie, Kotoh Kazuhiro, Taguchi Ken ichi, Nakamuta Makoto, Nawata Hajime, Watanabe Takeshi
Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
J Hepatol. 2002 Jun;36(6):786-92. doi: 10.1016/s0168-8278(02)00066-1.
BACKGROUND/AIMS: RCAS1, which is recognized by the specific antibody 22-1-1, was first identified as a tumor-associated antigen in gynecological carcinomas. RCAS1 is the ligand of a putative receptor present on lymphocytes, the expression of which is enhanced by lymphocyte activation. RCAS1 inhibits the growth of receptor-bearing cells and induces apoptotic death. Here we examined RCAS1 expression in biliary diseases.
RCAS1 expression was immunohistochemically examined on tissue samples. Apoptotic death was analyzed by DNA fragmentation detection method. RCAS1 production by cell lines was investigated by flow cytometry, enzyme-linked immunosorbent assay, and reverse transcription-polymerase chain reaction.
All cholangiocarcinoma cell lines examined clearly expressed RCAS1 at both the protein and RNA level. Immunohistochemically, RCAS1 was expressed in a high percentage of biliary adenocarcinomas (85.9% of intrahepatic cholangiocarcinomas, 96.4% of extrahepatic cholangiocarcinomas and gallbladder carcinomas). Apoptotic tumor-infiltrating lymphocytes could be found in these specimens. RCAS1 expression was frequently detected also in biliary epithelial cells in cases of immune-mediated cholangitis (74.2% in primary biliary cirrhosis, 66.6% in graft-versus-host disease), although the staining pattern for RCAS1 was different compared with cancer cells.
RCAS1 is highly expressed not only in cancer cells but also in non-tumor bile duct cells subjected to immune attack.
背景/目的：RCAS1可被特异性抗体22-1-1识别，最初被鉴定为妇科癌症中的一种肿瘤相关抗原。RCAS1是淋巴细胞上一种假定受体的配体，淋巴细胞激活可增强其表达。RCAS1抑制携带受体细胞的生长并诱导凋亡性死亡。在此，我们检测了RCAS1在胆道疾病中的表达。
采用免疫组织化学方法检测组织样本中RCAS1的表达。通过DNA片段化检测方法分析凋亡性死亡。采用流式细胞术、酶联免疫吸附测定和逆转录-聚合酶链反应研究细胞系中RCAS1的产生。
所有检测的胆管癌细胞系在蛋白质和RNA水平均清晰表达RCAS1。免疫组织化学结果显示，RCAS1在高比例的胆管腺癌中表达（肝内胆管癌中为85.9%，肝外胆管癌和胆囊癌中为96.4%）。在这些标本中可发现凋亡的肿瘤浸润淋巴细胞。在免疫介导性胆管炎病例的胆管上皮细胞中也经常检测到RCAS1表达（原发性胆汁性肝硬化中为74.2%，移植物抗宿主病中为66.6%），尽管RCAS1的染色模式与癌细胞不同。
RCAS1不仅在癌细胞中高表达，在遭受免疫攻击的非肿瘤胆管细胞中也高表达。
