FIGURE 5 from Novel Spirocyclic Dimer, SpiD3, Targets Chronic Lymphocytic Leukemia Survival Pathways with Potent Preclinical Effects Article Swipe
YOU?
·
· 2024
· Open Access
·
· DOI: https://doi.org/10.1158/2767-9764.25880285.v1
· OA: W4398204194
<p>SpiD3 synergizes with ibrutinib and elicits cytotoxic effects in ibrutinib-resistant CLL cells. <b>A–D,</b> Combination assays to test synergy between SpiD3 and ibrutinib (IBR; BTK inhibitor) in preclinical CLL models. HG-3 cells (<b>A–B</b>; <i>n</i> = 3 independent experiments) or CpG ODN 2006 (CpG; 3.2 µmol/L)-stimulated patient-derived CLL cells (<b>C–D</b>; <i>n</i> = 6) were treated with SpiD3, IBR, or both (1:1 ratio) for 72 hours. MTS assay was performed to detect the dose effect. <b>A</b> and <b>C,</b> Dose-effect of the single drugs and their combination (1:1 ratio). <b>B</b> and <b>D,</b> CI of the combined doses (0.5 µmol/L SpiD3 + 0.5 µmol/L IBR = 1 µmol/L on graph). CI values were calculated using the Chou-Talalay method by the software Compusyn. CI values >1 are antagonistic, CI values = 1 are additive, and CI values <1 are synergistic. <b>E,</b> Mitochondrial activity in parental wild-type (WT) and ibrutinib-resistant (IR) HG-3 cell lines were assessed by MTS assay following treatment with increasing concentrations of SpiD3 or IBR (72 hours; <i>n</i> = 6 independent experiments/cell line). IC<sub>50</sub> values (mean ± SEM) are noted for each cell line. <b>F</b> and <b>G,</b> Representative immunoblot analyses of p-BTK (Tyr223), total BTK, p-PRAS (Thr246), total PRAS, p-ERK1/2 (Thr202/Tyr204), total ERK1/2, MYC, PARP (total and cleaved), IKKα, IKKβ, p65, and RELB in WT- and IR-HG3 cells treated with SpiD3 (1–2 µmol/L) or IBR (1 µmol/L) for 4 hours. BCR activation was induced by adding soluble α-IgM (10 µg/mL) for the last 15 minutes of treatment (<i>n</i> = 5 independent experiments). GAPDH served as the loading control. <b>H,</b> Spleen-derived malignant B cells from terminally diseased Eµ-Myc/TCL1 mice (<i>n</i> = 8) were stimulated <i>ex vivo</i> with 1X PMA/Ionomycin and treated with SpiD3 (0.25–2 µmol/L), IBR (1 µmol/L), or JQ-1 (1 µmol/L) for 48 hours. Proliferation was assessed via MTS assay and normalized to the unstimulated vehicle (dashed line). Asterisks indicate significance versus stimulated vehicle. *, <i>P</i> < 0.05; **, <i>P</i> < 0.01; ***, <i>P</i> < 0.001.</p>