Figure 2.
Knocking down p21 and p27 abrogates the growth arrest response of IP6 in DU145 cells. DU145 cell variants were treated with or without 2 mM IP6 for 48 h and the number of viable cells (A) was determined as detailed in Materials and Methods. For clonogenic potential (B), DU145 cell line variants were seeded at a density of 1000 cells/well in 6-well plates and next day treated with or without 2 mM IP6. After 10 days, cells were fixed in methanol:acetic acid, stained with crystal violet, and the colonies were counted under inverted microscope as detailed in Materials and Methods. C, DU145 cell variants were treated with or without 2 mM IP6 for 48 h and then analyzed for cell cycle distribution, or cell lysates were prepared and immunoblotting was performed for p21, p27 and β-actin protein levels (inset) as detailed in Materials and Methods. C, control; *, P<0.001; NS, not statistically significant.