Figure 4.
Effect of two BCL2 anti-apopotic family inhibitors, ABT263 and Gx15-070, in TET cell lines. (a) MTS assay of ABT263 and Gx15-070 in TET and control cell lines. H146, H82 small cell lung cancer cell lines were used as references in ABT263 and H157 non-small cell lung cancer cell line in Gx15-070 experiments.27 Experiments were repeated four times. (b) In T1682 cells, ABT263 treatment increases MCL1 level compared with untreated cells or Gx15-070-treated cells. (c) T1889 was more sensitive to ABT263 and Sorafenib combination than to each single drug treatment as shown by MTS assay. Combination index (CI) values, reported on x axis, were calculated using Calcusync and demonstrated a synergistic effect for the drug combination: values <1 denotes synergism. Results for T1889 and TY82 are summarized in Supplementary Table S5. Experiments repeated three times. (d) Gx15-070 suppressed the growth of TY82 xenografts. Average fold change of tumor volume of 10 mice treated by Gx15-070 and 10 by vehicle alone are reported. The black arrow indicates the timing of treatment. (e) Cleavage of PARP and caspase-3 was assessed by western blot after 48-h treatment with various concentrations of Gx15-070 and ABT263 in T1682 cells. (f) Cell death induced by Gx15-070 and ABT263 was expressed as percentage of dead cells over total number of cells (cell death %). Cells were treated with the indicated concentrations of Gx15-070 and ABT263 for 48 h, stained with TOPRO3 and followed by flow cytometry analysis. Note that the highest effect of Gx15-070 in Ty82 cells was detected at 100 nM and was less pronounced at 1000 nM. This could be due to the off-target effect of Gx15-070 at high concentration that antagonized on-target effect of the drug (experiments were repeated two times)