||Two continuous cell lines, which were designated as EBC-1 and ABC-1, were
recently established from explant cultures of human squamous cell
carcinoma and adenocarcinoma of the lung in our laboratory. In the present
study, for the purpose of making an animal model of human lung cancer,
cells of EBC-1 and ABC-1 were transplanted into antilymphocyte serum (ALS)-
treated newborn hamsters and into nude mice.
The EBC-1 line was serially transplanted for 10 passages into ALS-treated
newborn hamsters. When 0.75-24.0×10^5 cells were inoculated
intraperitoneally or subcutaneously, 36 of 38 experimental animals
developed invasive tumors 19-35 days after implantation. Metastases to the
lungs were observed in 28 of 36 hamsters with tumors. The EBC-1 line was
also transplantable to nude mice, but the tumor growth was very slow and
serial transplantation was not successful.
The ABC-1 line was transplantable to ALS-treated newborn hamsters, but
propagated for only two passages. When 4.0-14.0×10^5 cells were inoculated
intraperitoneally or subcutaneously, 14 of 20 experimental animals
developed invasive tumors 28-33 days after implantation. The ABC-1 line
was transplantable, but not serially transplantable to nude mice.
In conclusion, EBC-1 when implanted into hamsters was a good model of
human lung cancer. To my knowledge, this is the first report of a high
frequency of lung metastases in the heterotransplantation of human lung
cancer. This animal model should be useful for various studies of human
lung cancer including mechanism of metastasis and chemosensitivity of