Fig. 2: Prostate cancer models with MCL1 copy number gain are sensitive to MCL1 inhibition.

A Violin plot of MCL1:Centromere (1p12) ratio in PNT2, LNCaP, C4-2, LNCaP95, 22Rv1, PC-3, and DU145 cell lines (n = 100 cells each). B Representative MCL1 FISH images (1 biological replicate; n = 100 cells). Scale bar = 10 µm. C MCL1, BCLXL, and BCL2 protein levels assessed by western blot in the same cell lines. GAPDH used as loading control. D Caspase 3/7 activity following AZD5991 (1 µM, left) or S63845 (1 µM, right) for 6 h using Caspase-Glo 2D. Mean ± Standard error (SEM) from three biological replicates, each with three technical replicates. Cell viability assessed by CellTiter-Glo 3D after 24 h (E) and 6 days (F) following treatment with six concentrations (1 µM highest, two-fold dilutions) of AZD5991 (left) or S63845 (right). Mean ± SEM from three biological replicates, each with three technical replicates is shown. Data depicted as fold change relative to vehicle (DMSO). G Workflow for mCRPC patient-derived xenograft (PDX) organoids (PDX-Os). Created in BioRender. Jimenez Vacas (2025) https://BioRender.com/7s2gcp5. H Violin plot of MCL1:Centromere (1p12) ratios in CP253c, CP336c, CP50c, CP267c (n = 100 cells each) and CP142c (n = 50). Median and IQR shown. One-way ANOVA with Tukeyʼs post-hoc test was performed. I Representative MCL1 FISH images of single PDX-O cells (1 biological replicate). Median MCL1:Centromere ratio shown. Scale bar = 5 µm. J Representative MCL1 IHC images from PDX tissues (single passage). Cytoplasmic H-score shown. Scale bar = 100 µm. K Caspase 3/7 activity (6 h) and organoid viability (24 and 96 h) in PDX-Os treated with AZD5991 or S63845 (1 µM), measured with Caspase-Glo 3D and CellTiter-Glo 3D. Mean ± SEM from three biological replicates, each with five technical replicates. Data shown as fold change relative to vehicle (DMSO). One-way ANOVA with Dunnett post-hoc test was performed. Source data are provided as a Source Data file.