Fig. 2.

cAMP-induced delay in cell cycle progression is not S-phase dependent. (A) MM370 (BRaf V600E) and MM485 (NRas Q61R) were synchronized by thymidine double block and released in the presence of DMSO or forskolin. Cells were fixed and lysed at the indicated times. Cell cycle progression was assessed by DNA content analysis and protein levels were assessed by Western blot with indicated antibodies. (B) MM370 cells were synchronized as described and released in the presence of DMSO, forskolin, or no treatment. Untreated cells were treated with forskolin 7 h postrelease toward the end of S phase. Cells were harvested and fixed at indicated time points and stained with PI for DNA content analysis. (C) MM370 cells were synchronized by thymidine double block and released. Seven hours postrelease, cells were treated with indicated MC1R and cAMP agonists. Cells were fixed at the indicated time points, and the cell cycle was assessed by PI staining. 4N fraction was quantified in the graph to the right.