Figure 4.

YA1 and Y27632 irreversibly suppress the formation of GEF16 transformed NIH3T3 colonies whereas, unlike Y27632, YA1 eliminates pre-existing transformed colonies. (A) Polyclonal GEF16 transfected cells were seeded at 2.0 × 10⁵ cells per 30 mm dish and incubated overnight. A measure of 10 μM YA1 or Y27632 was then added to each of these for 2, 4, 6, 8 and 10 days, respectively, where upon the cells were detached with trypsin and re-plated at a density of 2.0 × 10⁵ cells. After a further 10 days culture in the absence of inhibitors the cells were stained with Toluidine blue. (B) Polyclonal GEF16 and vector transfected cells were seeded at 2.0 × 10⁵ cells per 30 mm dish and incubated for 10 days after which 10 or 20 μM of either, YA1, Y27632 or DMSO control was added. These were incubated for 3 or 6 days then stained with Toluidine blue.