Rationale design of novel substituted 1,3,5-triazine candidates as dual IDH1(R132H)/ IDH2(R140Q) inhibitors with high selectivity against acute myeloid leukemia: In vitro and in vivo preclinical investigations

In this study, novel substituted 1,3,5-triazine candidates (4a-d, 5a-j, and 6a-d) were designed as second-generation small molecules to act as dual IDH1 and IDH2 inhibitors according to the pharmacophoric features of both vorasidenib and enasidenib. Compounds 6a and 6b for leukemia cell lines showed from low to sub-micromolar GI50. Moreover, compounds 4c, 5f, and 6b described the frontier antitumor activity against THP1 and Kasumi Leukemia cancer cells with IC50 values of (10 and 12), (10.5 and 7), and (6.2 and 5.9) µg/mL, which were superior to those of cisplatin (25 and 28) µg/mL, respectively. Interestingly, compounds 4c, 6b, and 6d represented the best dual IDH1(R132H)/IDH2(R140Q) inhibitory potentials with IC50 values of (0.72 and 1.22), (0.12 and 0.93), and (0.50 and 1.28) µg/mL, respectively, compared to vorasidenib (0.02 and 0.08) µg/mL and enasidenib (0.33 and 1.80) µg/mL. Furthermore, the most active candidate (6b) has very promising inhibitory potentials towards HIF-1α, VEGF, and SDH, besides, a marked increase of ROS was observed as well. Besides, compound 6b induced the upregulation of P53, BAX, Caspases 3, 6, 8, and 9 proteins by 3.70, 1.99, 2.06, 1.73, 1.75, and 1.85-fold changes, respectively, and the downregulation for the BCL-2 protein by 0.55-fold change compared to the control. Besides, the in vivo behavior of compound 6b as an antitumor agent was evaluated in female mice bearing solid Ehrlich carcinoma tumors. Notably, compound 6b administration resulted in a prominent decrease in the weight and volume of the tumors, accompanied by improvements in biochemical, hematological, and histological parameters.