[Testing bronchogenic carcinoma cells for sensitivity to cytostatics in vitro and in cell cultures].

The authors submit the first experience assembled in Czechoslovakia with testing of the sensitivity of bronchogenic carcinoma cells to cytostatics by the HTCA method (Human Tumor Clonogenic Assay). Based on work by A. W.

Kinetics of growth inhibition in a neoplastic population after repeated cytostatic treatment.

The analysis of growth kinetics of a neoplastic population after cytostatic treatment (radiation, chemotherapy) has been modeled by means of the cell cycle transition probabilities mu and transition intensities lambda. The transition between phases of the cell cycle and quiescent G0 cells during repeated cytostatic treatment has been exposed by the probabilistic model on the basis of the experimental data. The cytostatic treatment (the most effective time, dose and therapeutic combination) can be scheduled using established size and volume of the tumor and an estimate of cell proportion in various compartments of the neoplastic population.

Interactions between the growth effects of a kidney epithelial cell growth inhibitor and extracellular concentrations of cyclic nucleotides.

The effect of dibutyryl cyclic nucleotides, dbcAMP and dbcGMP, on the growth of BSC-1 cells has been studied in the presence and absence of kidney epithelial cell growth inhibitor. The growth response of the cells was dependent on concentrations of the dibutyryl cyclic nucleotides and on the presence or absence of serum in the medium. In the presence of serum, a high concentration (10(-3) M) of dbcGMP largely overcame the action of the kidney epithelial cell growth inhibitor.