Establishment of a new human extrahepatic bile duct carcinoma cell line (OCUCh-LM1) and experimental liver metastatic model.

A new human extrahepatic bile duct carcinoma cell line, designated OCUCh-LM1, was established from a liver metastatic lesion in a 61-year-old male. OCUCh-LM1 cells proliferated in a monolayered sheet with a population doubling time of 31 h. OCUCh-LM1 cells had an aneuploid pattern with a DNA index of 1.76, and chromosome counts showed a unimode of 63. OCUCh-LM1 cells expressed various carbohydrate antigens, including sialyl Lewis X, carbohydrate antigen 19-9 and SPan-1 antigen. Subcutaneous injections of OCUCh-LM1 cells induced tumour formation in nude mice. The reconstituted tumours were classified as well-differentiated adenocarcinoma. A daughter line, designated OCUCh-LM1-H1, was also established from liver metastatic colonies induced by splenic injection of OCUCh-LM1. OCUCh-LM1-H1 cells showed a higher potential for liver metastasis than OCUCh-LM1 (100% vs 20%). Since OCUCh-LM1 retains the initial characteristics (as of 93 passages at present) and expresses various carbohydrate antigens, the OCUCh-LM1 cell line and liver metastatic model established here will be useful for the study of the biological nature of extrahepatic bile duct carcinoma and the relationship between the expression of carbohydrate antigens and metastatic potential.