New Cell Cycle Checkpoint Pathways Regulators with 2-Oxo-indoline Scaffold as Potential Anticancer Agents: Design, Synthesis, Biological Activities and In Silico Studies

Novel benzofuran-conjugated indolin-2-ones as anticancer agents; design, synthesis, biological assessments, and molecular modeling insights

Poly (ADP-ribose) polymerase (PARP) inhibitors have been authorized for the treatment of breast cancer (BC) and prostate cancer (PC). Recent studies suggest that inhibiting angiogenesis through the vascular endothelial growth factor receptor (VEGFR) enhances cellular sensitivity to PARP inhibitors. This study presents the design, synthesis and full characterization of dual VEGFR-2 and PARP-1 inhibitors obtained by conjugating a PARP-1 inhibitor with VEGFR-2 inhibitor fragments (indole, benzofuran, and piperazine). Four compounds exhibited significant inhibitory activities against human prostate cancer cell lines (PC3) and breast cancer cell lines (MCF7) at 48 h. These compounds were identified as dual VEGFR-2 and PARP-1 inhibitors with low or sub-micromolar ranges, especially 12f, with IC50 values of 0.43 μM and 1.10 μM, respectively. Moreover, the potent compound 12f markedly decreased scratch wound closure and colony formation. Moreover, compound 12f significantly induced apoptosis in PC3 cells and arrested cells at the S phase. The dual inhibition of VEGFR-2 and PARP-1 protein kinase was further validated using western blotting. Applying molecular docking and dynamics determined the target compound's binding mechanism.

New 2-indolinone-indole hybrid compounds carrying a benzoyl moiety as tyrosine kinase inhibitors

In this study, new 2-indolinone-indole hybrid compounds (4a-s) carrying a benzoyl moiety were synthesized and their cytotoxic effects were examined against pancreatic (MIA-PaCa-2) and colon (HT-29 and HCT-116) cancer cells by MTT assays. Most of the tested compounds exhibited a better inhibitory activity and safety profile than the reference standard sunitinib malate against MIA-PaCa-2 and HCT-116 cancer cells. Compound 4e displayed the greatest cytotoxic effect on HCT-116 cell with an IC50 value of 0.16 µM and a remarkable selectivity profile (SI > 625). Compound 4g exhibited a selective activity against HCT-116 cancer cell (IC50 = 0.34 µM), with no activity against the other cells at the highest concentrations tested. Compound 4b demonstrated a potent inhibitory activity against MIA-PaCa-2 cell (IC50 = 0.54 µM). General tyrosine kinase inhibitor (TKI) activities and apoptotic effects were examined for compounds 4b, 4e and 4g. The tested compounds were observed to significantly reduce general TK activities in HCT-116 cell and induce apoptosis in HCT-116 and MIA-PaCa-2 cells. Lead compound 4e, the most effective general TKI, was determined to have a specific SRC kinase inhibitor effect in HCT-116 cell and the molecular modelling studies were performed to understand the potential binding mode at the ATP-binding domain of SRC kinase.

Pyrrolizine/indolizine-bearing (un)substituted isoindole moiety: design, synthesis, antiproliferative and MDR reversal activities, and in silico studies

Two new series of pyrrolizine/indolizine derivative-bearing (un)substituted isoindole moiety were designed and synthesized. The anticancer potential of the new compounds was evaluated against hepatocellular carcinoma (HepG-2), colorectal carcinoma, colon cancer (HCT-116), and breast cancer (MCF-7) cell lines. Compounds 6d and 6o were the most potent derivatives with IC50 values ranging from 6.02 to 13.87 μM against HePG-2, HCT-116, and MCF-7 cell lines. Moreover, methyl analog of the fluoro-substituted indolizine derivative 6m revealed significant antiproliferative activity against HePG-2, HCT-116, and MCF-7 cancer cell lines with IC50 values of 11.97, 28.37, and 19.87 μM, respectively. The most active anticancer analogs, 6d, 6m, and 6o, were inspected for their putative mechanism of action by estimating their epidermal growth factor receptor (EGFR) and cyclin-dependent kinase (CDK 2) inhibitory activities. Thus, compound 6o displayed the most inhibitory activity against EGFR and CDK 2 with IC50 values of 62 and 118 nM, respectively. Additionally, the quantitative real-time PCR analysis for the P-glycoprotein effect of compounds 6d, 6m, and 6o was performed, in which compound 6o illustrated significant down-regulation of P-gp against the HepG-2 cell line by 0.2732 fold. Mechanistic studies for the most active compounds involving the reversal doxorubicin (DOX) effect of compounds 6d, 6m, and 6o were performed, which illustrated cytotoxic activity with IC50 22.27, 3.88, and 8.79 μM, respectively. Moreover, the apoptotic activity of the most active derivative 6o on HCT-116 cancer cells showed accumulation in the G1 and S phases of the cell cycle.

One-Pot, Five-Component Condensation Reaction of Isatin, Secondary Amines, Malononitrile, Alcohols, and Molecular Oxygen to Access 3-Functionalized 2-Oxindoles

An efficient five-component condensation reaction of isatin, malononitrile, secondary amines, alcohols, and molecular oxygen was discovered. The reaction was performed in a one-pot fashion, and it does not require any metal catalyst. It gives straightforward access to structurally diverse 2-oxo-3-aminoindoline-3-carboxylates in moderate yields (70-88%). The scope of the reaction was successfully demonstrated by synthesizing a series of 3-functionalized 2-oxindoles by varying the isatin, amine, and alcohol components.

Novel Azine Linked Hybrids of 2-Indolinone and Thiazolodinone Scaffolds as CDK2 Inhibitors with Potential Anticancer Activity: In Silico Design, Synthesis, Biological, Molecular Dynamics and Binding Free Energy Studies

Molecular hybrid of 2-indolinone-thiazolidinone is a well known scaffold for variable biological activities including anticancer activity. Accordingly, in the current work aided with structure-based molecular modeling studies, a library of novel twenty-six hybrids, 4(a-z), was designed and synthesized. Docking studies in the active site of CDK2, one of the key checkpoints enzymes, revealed that the binding scores of the designed molecules are comparable to the reference enzyme's inhibitors Sunitinib, Nintedanib, and Semaxanib. Variable antiproliferative activities are shown for these molecules against human liver (HepG2), breast (MCF7), and colon (HCT-29) cell lines considering Doxrubacin as a refrence drug. Compared to cytotoxic activities on the normal fibroblasts (WI-38), the tested molecules had better selectivity against the cancerous cells, expressed by their selectivity index (SI), than Doxrubacin and compound 4i was the safest compound. CDK2 inhibitory results of compounds 4f, 4g, 4h, and 4w showed IC50 at 59.43, 143.6, 27.42, and 61.63 nM respectively, while that of Sunitinib was 23.8 nM. To clarify the obtained biological activities of these molecules, broad docking and molecular dynamic simulations studies were undertaken and confirmed the consistency between the computational and the in vitro CDK2 inhibitory activities. Furthermore, in silico ADME/Tox profiles were done for the most active molecules using SwissADME and pkCSM-pharmacokinetics web-based methods predicted good pharmacokinetics, bioavailability, and toxicity profiles for the tested compounds.