Characteristics and chemotherapeutic sensitivity of a human testicular cancer grown in artificially immunosuppressed mice.

Seven human testicular tumors were transplanted into artificially immunosuppressed mice. Two of them grew progressively (TT2 and TT6) and a serially transplantable line was developed from TT2. The xenografts maintained only the embryonal carcinoma components of originally mixed (embryonal cell carcinoma and choriocarcinoma) donor tumor. Although the histology did not change remarkably with passages, the xenografts lost their capacity to express human choriogonadotropin and alpha-fetoprotein. The latency period shortened, the growth rate remained similar with subsequent transplantations. The tumor cells of the TT2 line presented the human character according to chromosome analysis and were built up of two subsets of cells with a different DNA index estimated by flow cytometry. The embryonal cell carcinoma line was highly sensitive to CY and cisDDP. PVB combination was also effective, although the tumor growth inhibition proved to be only temporary.