Investigations on the instability of drug sensitivity in dependence on culture and transplantation conditions in case of a human lung carcinoma.

Changes of biological properties, DNA-distribution patterns and drug sensitivity testing in vivo and in vitro after different culture and transplantation conditions in case of a human lung carcinoma are described. While DNA-distribution patterns of cells before any culture (OSC, TC 0) showing two clearly different aneuploid cell populations (DNA-index DI: 3.9 and 4.9), cells after 8 passages (TC 8) in vitro demonstrate only one cell population. These cells do not differ from double value (4C) of diploid cells (2C). DNA-distribution patterns of cells of solid tumors grown in nude mice (nu/nu 2089-1) show a cell population with DI 6.3. In line with these results, cells and tissues after different culture and transplantation conditions exhibit variable drug sensitivities. The lung carcinoma (OSC) shows clear reactions measured either by 3H-thymidine or 3H-deoxyuridine in the presence of Cyclophosphamide and Methotrexate. Adriblastin and 5-Fluorouracil did not show any effects after 48 hours treatment. Cultivated cells (TC 8) were sensitive against all antineoplastic drugs tested. Tumor tissue grown in nude mice (nu/nu 2089-1) shows the strongest effect after 5-Fluorouracil treatment both in vitro and in vivo. Selection of different cell population were discussed with regard to these findings.