A HUMAN COMBINED HEPATOCELLULAR AND CHOLANGIOCARCINOMA CELL-LINE (KMCH-2) THAT SHOWS THE FEATURES OF HEPATOCELLULAR-CARCINOMA OR CHOLANGIOCARCINOMA UNDER DIFFERENT GROWTH-CONDITIONS

Background/Aims: Combined hepatocellular and cholangiocarcinoma is a r are tumor of the liver, and its histogenesis remains unclear. The auth ors addressed this issue in the current article, Methods: A specimen a septically obtained from the surgically resected combined hepatocellul ar and cholangiocarcinoma was processed for primary culture, The morph ologic features of the established cell line cultured on a plastic dis h and in type I collagen gel matrix, and transplanted in nude mice wer e examined,Results: The authors established a new human combined hepat ocellular and cholangiocarcinoma cell line, designated KMCH-2, from a 40-year-old Japanese man, KMCH-2 cells on a plastic dish proliferated in a monolayered sheet with a population doubling time of 32 to 44 h, KMCH-2 expressed functional characteristics of hepatocellular carcinom a, such as albumin synthesis at protein and mRNA levels, but were poor ly differentiated in morphology, showing an overlap of features with c holangiocarcinoma, KMCH-2 cells cultured within type I collagen gel ma trix proliferated, forming compact to vaguely trabecular and pseudogla ndular arrangements, and differentiated to show morphological characte ristics of hepatocellular carcinoma unlike the cells on a plastic dish , Mucin production was not detected in KMCH-2 cells in vitro, Subcutan eous tumors which developed in nude mice injected with KMCH-2 cells re presented features of adenocarcinoma with mucin production. Conclusion s: The present results revealed the presence of an albumin-producing h uman hepatic neoplastic cell, such as KMCH-2, that can differentiate t o show not only the features of hepatocellular carcinoma but also thos e of cholangiocarcinoma under certain growth conditions.