Abstract
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 0.75-24.0×105 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 4.0-14.0×105 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 anticancer agents.
