Figure 4

Influence of c-fos expression on the growth of T24 cells responding to antisense ODN and genistein treatments. (A) The level of c-Fos was highly expressed in mock-treated cells (lane 1), whereas the c-Fos protein level was greatly reduced 1 h after the anti-c-fos ODN (5 μ M) was added and the suppression lasted for several hours (lanes 2–5). The ratio line indicates the percentage of the protein produced in the ODN or/and genistein-treated cells vs untreated T24 cells. Under all experimental conditions, the levels of actin protein remained unchanged. (B) This plot demonstrates that the growth of T24 cells is not inhibited when adding the mutated ODN up to the concentration of 5 μ M, but the growth rates are greatly decreased, to essentially 40% of the mock-treated cells, when the same amount of the anti-c-fos ODN is present in cell cultures. Adding 50 μ M genistein to T24 cells pre-treated with 5 μ M mutated ODN affected the growth rate moderately (to about 60%), but the cells almost ceased to grow (to 10–15%) as the antisense ODN treatments (5 μ M) were combined with genistein. As an increased amount of the ODNs (10 μ M) was applied to the identical experiments described above, a similar result was obtained (data not shown). The symbols used here are: cells without any treatment, □; and cells treated with 0.5% DMSO, ▪; 50 μ M genistein, ; the mutated ODN, ▨; the mutated ODN supplemented with 50 μ M genistein, ; the anti-c-fos antisense ODN, ⍁; and the antisense ODN plus genistein, .