Figure 6. The Effect of MEK inhibitor on Mycoplasma-induced inhibitory effect on Topo I activity and on ERK 1/2 Phosphorylation in MCF7 cells.

MCF7 cells were pre-incubated with MEK inhibitors (PD) for 1 hour at a concentration of 25 µM followed by M. fermentans infection (MOI of 10³CFU/cell) for an additional 6 hrs. Total nuclear protein (12.5 ng) was added to a specific reaction mixture for Topo I. Reaction products were analyzed by agarose gel electrophoresis (A) and Topo I activity was quantified (B). Phosphorylated ERK 1/2 protein level from MCF7-extract was examined by Western blot analysis (C). Symbols: R and S are the relaxed and supercoiled form of the pUC19 DNA, respectively, Topo- no protein added to the reaction mixture t-test: ***p<0.005.