Fig. 6
From: Immunoproteasome function maintains oncogenic gene expression in KMT2A-complex driven leukemia
Synergistic targeting of oncogenic gene expression through pharmacologic inactivation of Menin and PSMB8. A Heatmap of differentially expressed genes in MOLM-13 cells. 1 μM MI-503 treatment, 1 μM MI-503 and 100 nM PR-957 treatment or DMSO for 72 h. Upregulated (red; FC > 2, p < 0.05) and downregulated (blue; FC < -2, p < 0.05) genes. B Representative plots (out of n = 3–4) showing protein expression of c-Myc, MEF2C, FLT3 and PBX3 upon treatment with DMSO, 100 nM PR-957, 1 μM MI-503 or 1 μM MI-503 + 100 nM PR-957 for 72 h in MOLM-13 cells. C Bar plots depicting cell counts in MOLM-13, MV-4;11, ML-2, KOPN-8 and OCI-AML3 cells after treatment with 20 nM PR-957, 200 nM MI-503, a combination of both or DMSO for 6 days. n = 4–5 independent experiments; mean with SD; paired Student t test. D-G Bar plots representing proliferation of MOLM-13 cells after treatment with indicated monotherapies, combinations or DMSO for 6 days. n = 3 independent experiments; mean with SD; paired Student t test. H Xenograft of human MOLM-13 cells: Survival curve of NXG recipient mice transplanted with 1 × 105 MOLM-13 cells pre-treated ex vivo with either 100 nm PR-957 (n = 5) for 48 h, 2.5 μM MI-503 (n = 15) for 96 h or a combination of 2.5 μM MI-503 for 96 h and 100 nM PR-957 for 48 h (n = 14). Four independent cohorts; Mantel-Cox test. I Patient derived xenograft (PDX): Schematic representation of the in vivo MI-503 (50 mg/kg, × 7), MI-503 + PR-957 (6 mg/kg, i.v., 5 days/week for 3 weeks) or 30% DMSO-70% NaCl0.9% (× 7) treatment of NXG mice (n = 5/treatment) injected with 2 × 104 KMT2A::AFF1 PDX-cells. BM cells were subsequently transplanted at limiting numbers (2 × 106, 2 × 105, 2 × 104) into NXG recipient mice. J Immunophenotyping of human CD45+ (hCD45+) cells in the BM of NXG mice after in vivo treatment with MI-503, MI-503 + PR-957 or DMSO/NaCl0.9%. n = 5 mice per treatment; Mann–Whitney U test. K-L Limiting dilution (LD) assay. K Reduction of leukemia initiating cells. L Cell dose, animal numbers, LSC-frequency and CI following diluent, MI-503 or PR-957 + MI-503 exposure. n= 4 per dilution and treatment; analysis was performed using ELDA software [28]