TMCG and DIPY act synergistically to induce apoptosis in breast cancer cells.

<p>(A) The left and central panels represent the effects of various DIPY concentrations on MDA-MB-231 and MCF7 cell growth, respectively, after 3 days of treatment in the absence (DIPY series; •) or the presence of 10 µM TMCG (TMCG/DIPY series; □). The right panel represents 4T1 cells that were treated for 3 days with vehicle only (DMSO; control), DIPY (5 µM), TMCG (10 µM) or a combination of the same concentration of DIPY plus TMCG. In all cases, the data are expressed relative to 100% growth or viability of the untreated control cells. *<i>P</i><0.05 compared with single TMCG and DIPY treatments. (B) Morphology of untreated breast cancer cells (control) compared with those subjected to 3 days of treatment with 10 μM TMCG and 5 μM DIPY (TMCG/DIPY). (C) The histograms represent the effects of DIPY and TMCG/DIPY treatment on apoptosis in MCF7 cells (*<i>P</i><0.05 relative to DIPY-treated cells). The dose-dependent effects after 3 days of treatment with DIPY were analysed using increasing concentrations of DIPY in the absence (DIPY series) or the presence of 10 μM TMCG (TMCG/DIPY series). (D) Apoptosis induction in MDA-MB-231 and 4T1 breast cancer cells after 3 days of treatment with vehicle (control), DIPY (5 μM), TMCG (10 μM) or a combination of the same concentration of DIPY plus TMCG was visualised by fluorescence microscopy of DNA stained with Hoechst 33342. The arrows indicate apoptotic cells. (E) MDA-MB-231 cells treated for 3 days with vehicle (control) or a combination of 10 µM TMCG and 5 µM DIPY (TMCG/DIPY) were examined for γH2AX nuclear foci (red). The nuclei were counterstained with DAPI (blue), and merged images are shown.