3D-AML drug screening in vitro. (A) Cell proliferation by ATP of 3D-MSCs cocultured with different primary AML samples, analyzed after 72 hours of venetoclax 0.005 µM, Ara-C 0.01 µM, quizartinib 0.2 µM, I-BET151 0.5 µM, and dasatinib 6 µM single treatment, and after combined therapy with lercanidipine 15 µM (dual targeting), normalized to the respective controls (DMSO; n = 3; treatments were performed in duplicate). (B) Analysis of combination index (CI) and synergistic effect for venetoclax, Ara-C, quizartinib, I-BET151, and dasatinib in combination with lercanidipine in 3D-AML model (CI <1.0 = synergistic effect). (C) Representative histogram of 3D-AML scaffolds after 72 hours of treatment with venetoclax either alone or in combination with lercanidipine, marked by Calcein-AM (green, survived cells, evaluated as area of the stack projection and normalized to DMSO) or by PI (red, dead cells, evaluated as ratio of PI red nuclei and blue Hoechst nuclei). Images are representative micrograph of double staining with Calcein-AM (green) and PI (red) of cells; ×20 magnification; scale bar, 100 µm. (D) Serial replating of AML cells harvested from 3D-AML model after 72 hours of treatment with chemo-targeted therapy and lercanidipine, alone or in combination (n = 5). ^#Absence of colonies. *P < .05, **P < .01.