Fig. 2.
ERK1/2 pathway inhibitors combine with the MCL1 inhibitor AZD5991 to kill melanoma cells. a–c A375 (a), SK-MEL-28 (b) and WM266-4 (c) cells were treated with the indicated concentrations of trametinib or vemurafenib in combination with AZD5991 for 5 days. The number of viable cells was determined at the point of treatment (day 0) and at the end of the experiment using Sytox Green. One-hundred percent represents the number of viable cells in the control wells at day 5, 0% is equivalent to the number of viable cells on day 0 and −100% indicates that no viable cells remained on day 5. d, e Twelve melanoma and 12 colorectal cancer (CRC) cell lines were treated with trametinib (Tra) or selumetinib (Sel) and AZD5991 or AZD4320 in an 8 × 8 concentration matrix for 5 days. Viable cell number (determined as above) was used to calculate Loewe synergy scores using the Loewe additivity model. P ≤ 0.01 (**), P ≤ 0.05 (*), ns (not significant) as determined by unpaired or paired two-tailed t-test. f A375 cells were treated with increasing concentrations of vemurafenib (Vem) with or without 1 μM AZD5991 for 48 h. Cell cycle profile was determined by propidium iodide staining and flow cytometry. g, h A375 cells were treated with increasing concentrations of vemurafenib (Vem) (g) or selumetinib (Sel) (h) with or without 1 μM AZD5991 for 48 h. i The indicated tumour cell lines were treated with DMSO control (C), 1 μM vemurafenib (Vem), 1 μM selumetinib (Sel) and 0.3 μM SCH772984 (SCH) alone or in combination with 1 μM AZD5991, 1 μM AZD4320 and 20 μM Q-VD-OPh (QVD) for 48 h. j–o A375 (j, k), COLO205 (l, m) or SW620 (n, o) cells were treated with increasing concentrations of AZD5991 (j, l, n) or AZD4320 (k, m, o) with or without 1 μM selumetinib (Sel) for 48 h. p, q A375 (p) and SK-MEL-30 (q) cells were treated with increasing concentrations of A-1155463 with or without 1 μM selumetinib (Sel) and 3 μM venetoclax for 48 h. g–q Apoptosis was assessed by Annexin V positivity using flow cytometry. Results (a–q) are the mean of at least three independent experiments and error bars show SD