T-2 TOXIN AFFECTS PROLIFERATION OF 3 DIFFERENT NEOPLASTIC CELL-LINES

The antiproliferative effect of T-2 toxin (T-2) towards mouse melanoma B16 cells, human myelogenous leukemia K562 cells, and human cervix ca rcinoma, HeLa cells, was studied. For the first four days of T-2 prese nce B16 cell survival was decreased in dose dependent fashion. However , cell survival after eleven days T-2 action may be dual: some stimula tion of cell growth that was direct function of the number of seeded c ells per well was observed and cell survival (for the highest number o f seeded cells) six times greater than control, was noticed at 20 nM T -2 toxin concentration. A smaller cell growth stimulation (cell surviv al more than 3 times higher than control) was observed with a lower ce ll number seeded per well. Nevertheless, by eleventh day concentration s of T-2 higher than 35 nM completely inhibited B16 cell proliferation , The same trend was noticed for T-2 action towards K562 cells. Treatm ent of HeLa cells with various T-2 concentrations led to a marked inhi bition of cell survival that was more pronounced at the end of 44(th) or 72(nd) hour, than after the 20(th) hour of agent's action. ICs50 va lues obtained in the present work, suggest that B16 cells were the mos t sensitive to T-2 antiproliferative action, while HeLa cells were the most resistant. When PBMC were cultured with HeLa cells the antagonis m against various T-2 concentrations was observed; cell survival deter mined after 44, or 72 hours of cells incubation, was less decreased co mpared to cultures treated with T-2, or with PBMC only. In addition, i t was shown that T-2 and cis-DDP had an antagonist effect on HeLa cell s survival.