Biological, functional and morphological characteristics of human bone and soft tissue tumors in nude mice

Since 1975, we have performed experiments on transplantation of bone and soft tissue tumors obtained, from 115 patients into nude mouse. In the present study, we analyzed biological, functional and morphological characteristics of the tumors transplanted in nude mice. The incidence of tumor take in the initial transplantation was 55.6% (40 of 72 cases) for malignant bone tumors, 42.9% (15 of 35 cases) for malignant soft tissue tumors and 0% for benign bone and soft tissue tumors. In particular, the incidence of tumor take was high for osteosarcoma (60%, 36 of 60 cases) and for rhabdomyosarcoma (70%, 7 of 10 cases). There were 22 tumors transplanted serially for more than 5 passages. The mean survival time for mice with serially transplantable bone and soft tissue tumors was 76.0 days and mean tumor growth index was 0.25. Serum LDH levels were as high as more than 5,000 Wrób. U for 8 of 12 lines tested. Serum ALP levels were normal for all tumors other than osteosarcoma. In mice transplanted with osteosarcoma, serum ALP levels were higher than 10 KAU for 8 of 13 lines tested. Pulmonary metastasis was seen in 5 of 9 osteosarcomas examined. For many of serially transplantable tumors, tumorigenicity was observed in nude mice by various transplantation routes including the subcutaneous, intraperitoneal and intravenous routes via the tail vain. Serially transplantable osteosarcomas were morphologically classified into three groups based on osteoid formation; those in which osteoid formation disappeared immediately, those in which osteoid formation decreased gradually, and those in which osteoid formation was unchanged or even increased. Osteoid was found for 6 of 13 lines examined. For 4 of the 6 tumors zone phenomenon was maintained during passages. For 2 lines among those in which osteoid disappeared, histological type was changed into quite another type from the original type of the tumor.