EFFECT OF THE TRANSFORMING GROWTH-FACTOR OF THE BETA-TYPE, EPIDERMAL GROWTH-FACTOR AND INSULIN ON THE INTENSITY OF SUBSTRATE-INDEPENDENT PROLIFERATION OF SARCOMA-CELLS IN MICE

Transforming growth factor-beta (TGF-beta, 0.05-50.0 ng/ml), epidermal growth factor (EGF, 2.5 ng/ml) and insulin (1 ng/ml) as well as their different combinations have been studied for their effect on the intensity of substrate-independent proliferation (colony-formation in the culture medium with 0.33 % of agar) of sarcoma cells in PS-103 line mice induced by subcutaneous implantation of polychlorvinyl plate to CBA mouse. lt was shown that TGF-beta stimulated such proliferation in the cells of 384/5 and 3sb clones which possessed a relatively low level of spontaneous colony-formation. At the same time it inhibited the proliferation in cells with a high level of spontaneous colony-formation. The latter could be seen in one of the subclones which had been obtained from the above mentioned 384/5 clone. EGF and insulin modulated such regulative effects of TGF-beta.