Search

Introduction: Posttranslational modification of proteins by reversible acetylation regulates key biological processes. Histone deacetylases (HDACs) catalyze protein deacetylation and are frequently dysregulated in tumors. This has spurred the development of HDAC inhibitors (HDACi). Such epigenetic drugs modulate protein acetylation, eliminate tumor cells, and are approved for the treatment of blood cancers., Objectives: We aimed to identify novel, nanomolar HDACi with increased potency over existing agents and selectivity for the cancer-relevant class I HDACs (HDAC1,-2,-3,-8). Moreover, we wanted to define how such drugs control the apoptosis-autophagy interplay. As test systems, we used human leukemic cells and embryonic kidney-derived cells., Methods: We synthesized novel pyrimidine-hydroxamic acid HDACi (KH9/KH16/KH29) and performed in vitro activity assays and molecular modeling of their direct binding to HDACs. We analyzed how these HDACi affect leukemic cell fate, acetylation, and protein expression with flow cytometry and immunoblot. The publicly available DepMap database of CRISPR-Cas9 screenings was used to determine sensitivity factors across human leukemic cells., Results: Novel HDACi show nanomolar activity against class I HDACs. These agents are superior to the clinically used hydroxamic acid HDACi SAHA (vorinostat). Within the KH-series of compounds, KH16 (yanostat) is the most effective inhibitor of HDAC3 (IC 50  = 6 nM) and the most potent inducer of apoptosis (IC 50  = 110 nM; p < 0.0001) in leukemic cells. KH16 though spares embryonic kidney-derived cells. Global data analyses of knockout screenings verify that HDAC3 is a dependency factor in 115 human blood cancer cells of different lineages, independent of mutations in the tumor suppressor p53. KH16 alters pro- and anti-apoptotic protein expression, stalls cell cycle progression, and induces caspase-dependent processing of the autophagy proteins ULK1 and p62., Conclusion: These data reveal that HDACs are required to stabilize autophagy proteins through suppression of apoptosis in leukemic cells. HDAC3 appears as a valid anti-cancer target for pharmacological intervention., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Production and hosting by Elsevier B.V.)

On account of their significance as apoptosis inducing agents, merging indole and 3-hydrazinoindolin-2-one scaffolds is a logic tactic for designing pro-apoptotic agents. Consequently, 27 hybrids (6a-r, 9a-f and 11a-c) were synthesised and evaluated for their cytotoxicity against MCF-7, HepG-2 and HCT-116 cancer cell lines. SAR studies unravelled that N-propylindole derivatives were the most active compounds such as 6n (MCF-7; IC 50 =1.04 µM), which displayed a significant decrease of cell population in the G2/M phase and significant increase in the early and late apoptosis by 19-folds in Annexin-V-FTIC assay. Also, 6n increased the expression of caspase-3, caspase-9, cytochrome C and Bax and decreased the expression of Bcl-2. Moreover, compounds 6i, 6j, 6n and 6q generated ROS by significant increase in the level of SOD and depletion of the levels of CAT and GSH-Px in MCF-7.

Triple-negative breast cancer (TNBC) is a highly aggressive malignancy with limited treatment options due to its heterogeneity and the lack of well-defined molecular targets. In our endeavour towards the development of novel anti-TNBC agents, herein we report a one-pot three-component synthesis of novel spirooxindoles 6a-p, and evaluation of their potential anti-proliferative activity towards TNBC MDA-MB-231 cells. Spirooxindoles 6a, 6e and 6i emerged as the most potent analogues with IC50 = 6.70, 6.40 and 6.70 µM, respectively. Compounds 6a and 6e induced apoptosis in MDA-MB-231 cells, as evidenced by the up-regulation of the Bax and down-regulation of the Bcl-2, besides boosting caspase-3 levels. Additionally, 6e displayed significant increase in the percent of annexin V-FITC positive apoptotic cells from 1.34 to 44%. Furthermore, spirooxindoles 6e and 6i displayed good inhibitory activity against EGFR (IC50 = 120 and 150 nM, respectively). Collectively, these data demonstrated that 6e might be a potential lead compound for the development of effective anti-TNBC agents. [ABSTRACT FROM AUTHOR]

Many bis-isatins and isatins with hydrazide extension were reported to have a potential anti-proliferative effects against different cancer cell lines and cancer targets. In this study, four series of bis-isatins with hydrazide linkers were synthesized. These compounds were investigated for their antitumor activity by assessing their cytotoxic potency against HepG2, MCF-7 and HCT-116 cancer cell lines. Compound 21c possessed significant cytotoxic activity against MCF-7 (IC 50 = 1.84 μM) and HCT-116 (IC 50 = 3.31 μM) that surpasses the activity of doxorubicin against both cell lines (MCF-7; IC 50 = 2.57 μM and HCT-116; IC 50 = 3.70 μM). Cell cycle analysis and annexin V-FITC staining of MCF-7 cells treated with 21c suggested that the cytotoxic effect of the compound could be attributed to its pro-apoptotic activity. [ABSTRACT FROM AUTHOR]

A novel series of N -substituted-4-phenylphthalazin-1-ones 14a – g bearing different anilines at the N-2 of phthalazin-1-one scaffold via acetyl-flexible linker was designed and synthesized for the development of potential anticancer agents. Compounds 19a – g were synthesized by insertion of methylene (CH 2 ) bridge at C4-position of 14a – g to provide a flexibility for the phenyl group. The newly synthesized compounds 14a – g and 19a – g were evaluated for their anti-proliferative activity against three human tumor cell lines HepG2 hepatocellular carcinoma, HT-29 colon cancer and MCF-7 breast cancer. In particular, HepG2 and HT-29 cancer cell lines were more susceptible to the synthesized derivatives. Compound 19d (IC 50 = 1.2 ± 0.09 μM) was found to be the most potent derivative against HepG2 as it was 2.9 times more active than doxorubicin (IC 50 = 3.45 ± 0.54) and sorafenib (IC 50 = 3.5 ± 1.04 μM). Compounds 14e , 14g , 19d and 19g with IC 50 = (3.29 ± 0.45), (3.50 ± 0.846), (1.20 ± 0.09) and (3.52 ± 0.70) μM, respectively, were found to be active candidates against HepG2 cancer cells. Compounds 14e , 14g , 19d and 19g were able to induce apoptosis in HepG2, this was assured by; the significant increase in the percentage of annexin V–FITC-positive apoptotic cells (UR + LR), the down-regulation of the anti-apoptotic protein Bcl-2 and the up-regulation of the pro-apoptotic protein Bax, in addition to boosting caspase-3 levels. Moreover, cytotoxicity evaluation of the newly synthesized compounds in HT-29 revealed that compounds 14e , 14f , 19e and 19f (IC 50 = 3.05 ± 0.78, 4.02 ± 1.18, 3.68 ± 0.79 and 2.98 ± 0.47 μM, respectively) were more potent than doxorubicin (IC 50 = 7.70 ± 1.78 μM). [ABSTRACT FROM AUTHOR]

[Display omitted] • Three series of 4-substituted pyridopyrimidin derivative were synthesized. • The target compounds were screened for their EGFR inhibitory activity. • The most active compounds were screened for their cytotoxicity. • Compound 4b was subjected to cell cycle analysis and apoptotic assay. • A molecular modeling study was achieved. The present study describes the synthesis of three series of 4-substituted pyridopyrimidin derivatives 4a-h, 5a-d. 6a-d, starting from 2-amino-6-(4-methoxyphenyl)-4-(4-(substituted) phenyl)nicotinonitrile 2a-d via the reaction with N , N -dimethyl- N -' substituted phenyl formimidamide to obtain 4a-h or with either phenyl isothiocyanate 1:1 and 1:2 to obtain 5a-d , 6a-d respectively. The synthesized compounds were evaluated for their effectiveness as EGFR inhibitors against Gefitinib. Six compounds; 4b,g,h, 5c and 6a,d prompted significantly higher EGFR inhibitory activity relative to that of Gefitinib. While two compounds 4d and 4f showed IC 50 values non-significantly different from that of the reference drug. Furthermore, compounds 4a, 4 h, 6a and 6d were chosen to be assessed in vitro for their cytotoxicity against two EGFR -overexpressing cell lines; two human cancer cell lines namely: MCF7 and MDA-MB - 361. Moreover, cell cycle analysis and apoptotic assay was applied for compound 4b that showed most potent inhibitory activity on EGFR, and the highest cytotoxicity against MCF7 and MDA-MB-361, where cell cycle arrest was achieved at pre G and S phases with increased apoptosis. Additionally, a molecular docking study was achieved to inspect the interaction of this compound with the active site of EGFR-TK. [ABSTRACT FROM AUTHOR]