Figure 2.

CCEU and ICEU block B16 cell cycle at G₁/S and at G₂/M transition, respectively. (a) Typical flow cytometry analysis with propidium iodide showing a decrease of cells in S phase, whereas the number of cells in G₁ phase increased after CCEU treatment. In contrast, ICEU treatment leads to a major increase of cells in G₂ phase due to a block in the G₂/M transition, when compared to DMSO-treated cells (control). (b) Distribution of cells in the different cell-cycle phases expressed as percentages. Statistical differences are found between controls and treated cells by the χ² test (P<0.05). (c) Western blot analysis: ICEU, but not CCEU, modified the migration properties of β-tubulin in extracts of B16 cells. CCEU, cyclohexylphenyl-chloroethyl urea; ICEU, iodophenyl-chloroethyl urea.