FIGURE 1.

Safranal inhibits DNA synthesis and re-proliferation following induction of cell cycle re-entry. Chemical structure of safranal (A). Quiescent LNCaP (B) and PC-3 (C) cells were induced to re-enter the cell cycle, treated with the indicated concentrations of safranal for 72 h, and subjected to the SYBR Green assay to assess their DNA content. Quiescent LNCaP (D) and PC-3 cells (E) were stimulated to re-enter the cell cycle in the presence or absence of safranal (GI₅₀ or GI₉₀) for 24 and 48 h, respectively. The cells were subsequently cultured in fresh full medium for 2 weeks, followed by ethanol fixation, crystal violet staining, and imaging. Representative images and quantification data of LNCaP and PC-3 cell colonies are presented. All data are shown as mean ± SD of triplicate experiments. **P < 0.01, ***P < 0.001 vs. vehicle control. Cont, control cells (non-quiescent cells); Qsct, quiescent cells (7-day serum withdrawal for LNCaP or 3-day contact inhibition for PC-3).