Fig. 6: In vivo delivery of miR-142 mimic reduced BC CML burden in GEMMs and PDXs.

In vivo a Ex vivo uptake of Cy3-labeled CpG-M-miR-142 in LSK cells by flow cytometry. b In vivo uptake of Cy3-labeled CpG-M-miR-142 by flow cytometry and mRNA expression of the miR-142 target Cpt1a by Q-RT-PCR in LSKs from normal mice treated with a single dose of Cy3-labeled CpG-M-miR-142 (20 mg/kg) (n = 5 biologically independent samples per group). c MiR-142^−/−BCR-ABL CML mice (BCR-ABL were induced for two weeks by tet-off) were treated with CpG-M-miR-142 or SCR (20 mg/kg/day, IV) for 3 weeks, then levels of miR-142 and its target Cpt1a in BM MNCs from these treated mice were measured by Q-RT-PCR (n = 10 biologically independent samples per group). d Experimental design. To determine the impact of in vivo rescuing of miR-142 deficit on the BC transformation rate, a cohort of miR-142^−/−BCR-ABL mice were treated with CpG-M-miR-142 (20 mg/kg/day, iv) or SCR for 4 weeks, starting on the day after tet-off induced BCR-ABL induction. e At treatment completion, white blood cell (WBC) counts, circulating LSKs by flow cytometry, BM blasts by microscopy (scale bar: 10 µM), and survival of the CpG-M-miR-142-treated vs SCR-treated mice are shown. f To assess the impact of CpG-M-miR-142 treatment on the LSC burden, 10⁶ BM cells from the above CpG-M-miR-142- or SCR-treated mice (CD45.2) were transplanted into secondary (2nd) recipient mice (CD45.1). WBC counts, engraftment (CD45.2⁺) rates, and survival of the 2nd recipients are shown. g Experimental design. BC CML patient-derived xenograft (PDX) mice were generated by transplanting 2 × 10⁶ CD34⁺ cells from BC CML patients into NSG mice. Upon detecting engraftment (>5% blood human CD45⁺ cells) at two weeks post transplantation, these mice were treated with CpG-M-miR-142 (20 mg/kg/day, iv) or SCR for 3 weeks. h BM miR-142 levels (n = 4 biologically independent samples per group) and survival of these treated mice (n = 6 mice per group) are shown. i BM cells from these treated mice were transplanted into 2nd NSG recipient mice (10⁶/mouse) and PB engraftment (human CD45⁺) rates and survival of the 2nd recipient mice (n = 9 mice per group) are shown. For b, c, e, f and h, i, source data are provided as a Source Data file. For a, b, e, results from one of the three independent experiments are shown (n = 3). Comparison between groups was performed by two-tailed, unpaired t-test. Survival curve was compared by Log-rank test. Results shown represent mean ± SEM.