BRD4 and PI3K dual inhibitors MDP1 and MDP5 promote MB cell arrest in G1 phase and apoptosis but inhibits colony formation more efficiently than SF2523. DAOY and HD-MB03 cells were treated with SF2523, MDP1, and MDP5 at the dose of 5.0 μM for 48 h. A and B Histogram shows the quantitative analysis of cell cycle assay (n = 5, mean ± S.D., p < 0.05). Cells treated with SF2523 and MDP5 show cell cycle arrest in G1 phase as compared to control and MDP1. C Treatment with MDP5 showed lower number of colonies in both the cell lines. D and E Apoptotic assay (n = 5, mean ± S.D., *p < 0.05). F Relative mRNA expression levels (%) of BCL2 and Cyclin D1 genes after 48 h incubation with SF2523, MDP1 and MDP5.