“…These high apoptotic percentages shown by (R)-1 are consistent with the G 1 and G 2 /M arrest since cells exposed to specific agents typically enter apoptosis from a given phase of the cell cycle (Saunders et al, 1997;Marchal et al, 2004;Lundberg & Weinberg, 1999). Differences in cytotoxicity, cell cycle analysis or apoptotic levels between (R)-1 and (S)-1 suggest distinct signalling pathways as has been shown with other anti-tumour enantiomers (De Fátima et al, 2008). Moreover, it is possible that the amount of cells undergoing apoptosis in response to the compounds have been higher than these values, because only adherent cells were stained and counted.…”