Nepyyvoda K. Biochemical characteristics and parameters of the functional activity of tumor cells in response to epidermal growth factor during deficit of serum factors.

Significant paracrine and autocrine influence of epidermal growth factor (EGF) family peptides on biochemical and functional characteristics of breast cancer tumor cells MCF-7 in case of serum-free culture condition was revealed. It was shown that autocrine level of EGFR-like peptides production in case of 2D growth and deficit of serum factors is 17,9 ±1,3 ng/106 cells, that in 2,5 times more, than in case of 3D growth. Decrease of cell dehydrogenfses activity in serum-free cultured MCF-7 cells was shown, compare to analogous control, however lactatedehydrogenase activity increased in 1,5 and 2,2 times (р<0,05) on 48 and 72 hour of culturing, respectively, that correlated the same way with glucose uptake level. For MCF-7 cells, in standard culturing conditions square of migration on the substrate increased proportionally to incudation duration. If in 24 hours area of cell migration increased to 9,6 mkm2, so in 96 hours this indicator erased to 14,2 mkm2. During cultivation of MCF-7 cells in serum-free conditions formation of spheroid aggregates and also dead cells was detected, that was confirmed by cytofluoromenry, MMT-test and tripane blue cells staining. Influence of EGF and its antagonists (antibodies to EGFR type І and ІІ, teralok, and herceptin, respectively) on MCF-7 cells cultured in different conditions appeared in 60% mitogenic stimulation of cell proliferation under the influence of EGF, decreased the number of dead cells in case of serum-free culture condition, inhibition of glucose uptake. In case of combined effect of EGF and its antagonists teralok and herceptin on MCF-7 cells antiproliferative effect of teralok with EGF is 56±9,6% relatively to control, and teralok is 45±7,5%; cytotoxic effect of teralok in combined application with EGF was not detected. Conversely herseptin does not have antiproliferative effect in combination with EGF, 60±10,3% cytotoxic effect was found, while mono efect of herceptin is only 23% compare to control.