Relationship between interleukin-6 and proliferation and differentiation in cholangiocarcinoma.
OBJECTIVE
Interleukin-6 (IL-6) has been implicated as a mediator of growth control in several human neoplasms. The significance of IL-6 expression in human cholangiocarcinoma was examined in this study.


RESULTS
IL-6 expression was examined in 43 surgically resected cholangiocarcinomas and a cholangiocarcinoma cell line CCKS1, derived from abdominal metastasis of moderately differentiated adenocarcinoma, by immunohistochemical and in-situ hybridization techniques. In non-neoplastic bile ducts, IL-6 was constitutively but weakly expressed. In surgical cases of cholangiocarcinoma, IL-6 was frequently and strongly expressed in the cytoplasm of well-differentiated cholangiocarcinoma, while its expression was decreased, and less intense or absent in moderately and poorly differentiated areas, respectively. IL-6 mRNA was detected in the cytoplasm of carcinoma cells of two cases of cholangiocarcinomas positive for IL-6. IL-6 was detected in hepatic bile from two cholangiocarcinoma cases studied. The proliferation antigen Ki67 was found to be more frequently expressed in IL-6 negative carcinoma cells than in IL-6 positive carcinoma cells (P < 0.01). In cultured carcinoma cells line CCKS1, IL-6, IL-6 mRNA and IL-6 receptor alpha chain were detected in the cytoplasm of carcinoma cells, suggesting an autocrine effect of IL-6 on carcinoma cells.


CONCLUSIONS
IL-6 expression is inversely related to cell proliferation and positively related to differentiation in cholangiocarcinoma.
Department of Pathology (II), Kanazawa University School of Medicine, Japan.
H
H
Sugawara
M
M
Yasoshima
K
K
Katayanagi
N
N
Kono
Y
Y
Watanabe
K
K
Harada
Y
Y
Nakanuma
D000368:Aged; D000818:Animals; D001646:Bile / Q000276:immunology; D001650:Bile Duct Neoplasms / Q000276:immunology* / Q000473:pathology; D001653:Bile Ducts, Intrahepatic; D015153:Blotting, Western; D002454:Cell Differentiation; D002455:Cell Division; D018281:Cholangiocarcinoma / Q000276:immunology* / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D015850:Interleukin-6 / Q000378:metabolism*; D019394:Ki-67 Antigen / Q000378:metabolism; D008297:Male; D051379:Mice; D008819:Mice, Nude; D008875:Middle Aged; D009368:Neoplasm Transplantation; D012333:RNA, Messenger / Q000032:analysis; D014407:Tumor Cells, Cultured
D015850:Interleukin-6; D019394:Ki-67 Antigen; D012333:RNA, Messenger