Establishment of a human hepatoblastoma model in athymic nude mice. Producibility of fatty acid-binding protein, alpha-fetoprotein, and alpha 1-acid glycoprotein.

An athymic nude mouse model of human hepatoblastoma, designated HBL-2, was established. HBL-2 produced alpha-fetoprotein (AFP) and the serum level in tumor-bearing mouse was roughly proportional to the tumor weight. Reactivity of AFP to Concanavalin A and Lens culinaris lectins indicated that it contained predominantly fucosylated, non-bisecting N-acetylglucosamine as a sugar moiety. Alpha 1-acid glycoprotein (AAG) was also found in both HBL-2 tumor extract and sera of tumor-bearing mice. The serum level, however, was not proportional to either the tumor weight or the value of the tumor extract. In addition, fatty acid-binding protein (FABP) was detected in approximately 40% of tumor cells and in tumor extract with polyclonal antibody against liver FABP. Thus, HBL-2 is an unique model of human hepatoblastoma, in that it produces FABP in addition to AAG and AFP.