The influence of a new antitumor agent on hemopoietic colony forming cells

The cytostatic and immunsuppressive agent N'-methyl-N'-beta-chloroethylbenzaldehyde hydrazone (B1) in in-vitro experiments has a stimulating effect on colony-forming culture (CFUc) of bone marrow from C57BL mice. This unusual behaviour, which is in contrast to other cytostatics, could also be observed in vitro with CFUc obtained from mice treated with therapeutic doses of B1 for 2 weeks. This stimulation is not a particular effect of B1 alone but seems to depend on a synergistic effect of the combination of B1 and the colony-stimulating activity (CSA) present in the serum from endotoxin-treated mice (MP) in the testing system. The results suggest that the described effect of B1 is due to an interference at the cell membrane of CFUc or their precursor cells.

The influence of N-methyl-N-beta-chloroethyl hydrazines on the mitotic index of Ehrlich ascites tumor cells and the leukopoiesis of the mouse

The cytostatic activity of N'-methyl-N'-beta-chloroethylbenzaldehyd hydrazone (B1) is at least equal to that of procarbazine when its effect is tested with the Ehrlich ascites tumor cells of the mouse and the Yoshida sarcoma of the rat. B1 causes a slighter decrease of mitotic cells and no shift from prophase to metaphase. These results suggest that the cytostatic effect of B1 is due to interference with cell metabolism or an effect at the cell membrane and not to an effect on cell proliferation. This assumption is supported by a considerable depression of lymphocytes and a minor effect on granulopoiesis, which is especially sensitive towards proliferation toxins. All these findings suggest a different mechanism of action of B1 and procarbazine.