Synthesis and molecular modeling of new benzimidazoles as glutathione S-transferase inhibitors and anticancer agents

New thiazolidin-4-ones as anti-cervical cancer agents targeting EGFR: design, synthesis, and computational studies

AIM

A new series of 3,4-dihydronaphthalen-1(2 h)-ylidene)hydrazineylidene)-5-substituted thiazolidin-4-one derivatives were designed and synthesized.

RESULTS & METHODOLOGY

The new compounds were screened for in vitro antitumor activity against Hela cancer cell line. The compounds 7b, 7 h, and 7i produced more potent cytotoxicity than doxorubicin with IC50 values of 1.83 ± 0.1, 2.54 ± 0.14, 2.75 ± 0.15, and 3.63 ± 0.2 μM, respectively. They also showed a promising safety profile against WI-38 normal cells. In addition, compound 7b produced a promising multi-kinase inhibition against EGFR (WT) while being very selective toward the mutant forms (L858R and T790M) with IC50 values of 0.099 ± 0.006, 0.064 ± 0.006, and 0.026 ± 0.007 μM, respectively, in comparison to gefitinib and osimertinib. A study of the cell cycle in Hela cells showed that 7b arrests cell cycle in the pre-G1 phase and causes early and late apoptosis. Eventually, the molecular docking results showed that 7b had good-binding interactions with EGFRWT, EGFRL858R, and EGFRT790M.

CONCLUSION

Compound 7b was predicted to have promising oral absorption, good drug-likeness, and low toxicity risks in humans. Moreover, MD simulations confirmed the stable complexes of 7b with EGFRWT, EGFRL858R, and EGFRT790M (with RMSD 0.12-0.35 nm, RMSF 0.2-0.55 nm, SASA 140-150, and Rg 1.80-2.00 nm).

Immunotherapeutic effects of de novo benzimidazole derivative and prebiotic bacterial levan against triple-negative breast tumors by harnessing the immune landscape to intercept the oncogenic transcriptome

The current study aimed to investigate the therapeutic potential of a novel benzimidazole derivative (BMPE) and a prebiotic bacterial levan (LevAE) against triple-negative breast cancer (TNBC) in a 4T1-cell syngeneic mouse model and to elucidate the immunological and molecular mechanisms underlying the phenotypic changes observed in treated tumors. The metastatic TNBC model was successfully established by subcutaneous inoculation of 100 μl of 4T1 cell suspension (~6000 cells) in the mammary glands of adult female BALB/c mice after brief immunosuppression one day before cell implantation. The therapeutic efficacy of BMPE and LevAE was biochemically, immunologically, and immunohistochemically evaluated. Both compounds exhibited significant antitumor and antimetastatic effects through modulating the tumoral and systemic immune milieus and restoring the TME redox status, which ultimately suppressed the oncogenic transcriptome in the treated breast tumors. Compared to the reference drug (Doxorubicin), BMPE treatment resulted in nearly complete remission within 21 days of treatment, whereas LevAE was less convenient but produced a significant curative outcome. In light of these findings, BMPE and LevAE provide new paradigms for cancer immunotherapy.

pH-tailored delivery of a multitarget anticancer benzimidazole derivative using a PEGylated β-cyclodextrin-curcumin functionalized nanocomplex

In this study, we aimed to enhance the bioavailability of a benzimidazole derivative with potent anticancer potential through a nano-based approach. Benzimidazole-loaded polyethylene glycol-β-cyclodextrin-functionalized curcumin nanocomplex (BMPE-Cur) was prepared and characterized for its physicochemical properties and drug release profiles under different pH conditions. In addition, the biological activities of the nanocomplex including antioxidant potentials and pro-apoptogenic properties, against HepG2, PC3, and the chemo-resistant MCF-7-ADR cell lines relative to the normal Wi-38 cell line were in vitro assessed and compared with those of the free benzimidazole compound. In addition to FTIR, XRD, and NMR spectral studies, a polymeric nanocomplex with an average particle size of 467.7 nm and high stability was successfully developed, as indicated by the negative zeta potential (-28.24 mV). The nanocomplex also showed prolonged pH-sensitive sustained drug release under conditions that replicated the tumor's extra/intracellular pH. The formulated nanocomplex also demonstrated potent radical scavenging capacity owing to the inclusion of curcumin, a known radical quencher. In addition, compared with the free compound, BMPE-Cur induced DNA fragmentation-driven cell cycle arrest in HepG2, PC3, and MCF-7-ADR cells at the G1/S, G1 & S phases; respectively, with remarkable selectivity. In conclusion, the newly formulated BMPE-Cur nanocomplex represents an attractive multitarget anticancer candidate.

Benzimidazole scaffold as a potent anticancer agent with different mechanisms of action (2016-2023)

Benzimidazole scaffolds have potent anticancer activity due to their structure similarity to nucleoside. In addition, benzimidazoles could function as hydrogen donors or acceptors and bind to different drug targets that participate in cancer progression. The literature had many anticancer agents containing benzimidazole cores that gained much interest. Provoked by our endless interest in benzimidazoles as anticancer agents, we summarized the successful trials of the benzimidazole scaffolds in this concern. Moreover, we discuss the substantial opportunities in cancer treatment using benzimidazole-based drugs that may direct medicinal chemists for a compelling future design of more active chemotherapeutic agents with potential clinical applications. The uniqueness of this work lies in the highlighted benzimidazole scaffold hybridization with different molecules and benzimidazole-metal complexes, detailed mechanisms of action, and the IC50 of the developed compounds determined by different laboratories after 2015.

The mechanisms of multidrug resistance of breast cancer and research progress on related reversal agents

Chemotherapy is the mainstay in the treatment of breast cancer. However, many drugs that are commonly used in clinical practice have a high incidence of side effects and multidrug resistance (MDR), which is mainly caused by overexpression of drug transporters and related enzymes in breast cancer cells. In recent years, researchers have been working hard to find newer and safer drugs to overcome MDR in breast cancer. In this review, we provide the molecule mechanism of MDR in breast cancer, categorize potential lead compounds that inhibit single or multiple drug transporter proteins, as well as related enzymes. Additionally, we have summarized the structure-activity relationship (SAR) based on potential breast cancer MDR modulators with lower side effects. The development of novel approaches to suppress MDR is also addressed. These lead compounds hold great promise for exploring effective chemotherapy agents to overcome MDR, providing opportunities for curing breast cancer in the future.

Toxicological profiling of a de novo synthesized benzimidazole derivative with potent and selective proapoptotic potentials against breast cancer

This study aimed to investigate the toxicological profile of 1-(6-(1H-benzo[d]imidazole-2-yl)-2-methylpyridin-3-yl) ethanone (BMPE), both in vitro and in vivo. The proapoptotic/necrotic and cell cycle arrest potentials of BMPE were assessed in MCF-7 cell line. The in vivo toxicology was assessed in female Balb/c mice by repeated dosing of 5, 25, and 50 mg/kg for 21 consecutive days, then different biochemical, inflammatory, and oxidative markers were assessed in sera/tissue homogenates of treated animals. The new derivative showed a potent selective cytotoxicity against malignant cell lines with IC50 value 0.2 μM/mL, while the cytotoxic effect on normal Wi-38 cells was observed at IC50 value 0.4 μM/mL; i.e. twofold the effective anticancer dose. BMPE exhibited an early DNA fragmentation-derived cell apoptosis observed at the G0/G1 checkpoint. In vivo, BMPE was biochemically/immunologically tolerable at a pharmacological dose range of 5-25 mg/kg, with no significant rates of mortality/morbidity and minimal-to-moderate histopathological alterations recorded. The new derivative represents an attractive therapeutic candidate for breast cancer, considering its noticeable modulatory effect on the oxidative-inflammatory axis that would relate to its potent antitumor effect.

Synthesis and biological evaluation of new derivatives of thieno-thiazole and dihydrothiazolo-thiazole scaffolds integrated with a pyrazoline nucleus as anticancer and multi-targeting kinase inhibitors

Deregulation of various protein kinases is considered as one of the important factors resulting in cancer development and metastasis, thus multi-targeting the kinase family is one of the most important strategies in current cancer therapy. This context represents the design and synthesis of two sets of derivatives bearing a pyrazoline-3-one ring conjugated either with a thieno[3,2-d]thiazole or with a dihydrothiazolo[4,5-d]thiazole scaffold via an NH linker, 3a–d and 5a–d respectively, using the pyrazolinone–thiazolinone derivative 1 as a key precursor. All the newly synthesized compounds were assessed in vitro for their anticancer activity against two cancer cell lines (MCF-7 and HepG-2). The safety profile of the most active cytotoxic candidates 1 and 3c was further examined against the normal cell line WI-38. The compounds 1 and 3c were further evaluated as multi-targeting kinase inhibitors against EGFR, VEGFR-2 and BRAF^V600E, exhibiting promising suppression impact. Additionally, the latter compounds were investigated for their impact on cell cycle and apoptosis induction potential in the MCF-7 cell line. Moreover, the antimicrobial activity of all the new analogues was evaluated against a panel of Gram-positive and Gram-negative bacteria, yeast and fungi in comparison to streptomycin and amphotericin-B as reference drugs. Interestingly, both 1 and 3c showed the most promising microbial inhibitory effect. Molecular docking studies showed promising binding patterns of the compounds 1 and 3c with the prospective targets, EGFR, VEGFR-2 and BRAF^V600E. Finally, additional toxicity studies were performed for the new derivatives which showed their good drug-like properties and low toxicity risks in humans.

Deregulation of various protein kinases is considered as one of the important factors resulting in cancer development and metastasis, thus multi-targeting the kinase family is one of the most important strategies in current cancer therapy.

Imidazoles as Potential Anticancer Agents: An Update on Recent Studies

Nitrogen-containing heterocyclic rings are common structural components of marketed drugs. Among these heterocycles, imidazole/fused imidazole rings are present in a wide range of bioactive compounds. The unique properties of such structures, including high polarity and the ability to participate in hydrogen bonding and coordination chemistry, allow them to interact with a wide range of biomolecules, and imidazole-/fused imidazole-containing compounds are reported to have a broad spectrum of biological activities. This review summarizes recent reports of imidazole/fused imidazole derivatives as anticancer agents appearing in the peer-reviewed literature from 2018 through 2020. Such molecules have been shown to modulate various targets, including microtubules, tyrosine and serine-threonine kinases, histone deacetylases, p53-Murine Double Minute 2 (MDM2) protein, poly (ADP-ribose) polymerase (PARP), G-quadraplexes, and other targets. Imidazole-containing compounds that display anticancer activity by unknown/undefined mechanisms are also described, as well as key features of structure-activity relationships. This review is intended to provide an overview of recent advances in imidazole-based anticancer drug discovery and development, as well as inspire the design and synthesis of new anticancer molecules.

Glutathione S-Transferases in Cancer

In humans, the glutathione S-transferases (GST) protein family is composed of seven members that present remarkable structural similarity and some degree of overlapping functionalities. GST proteins are crucial antioxidant enzymes that regulate stress-induced signaling pathways. Interestingly, overactive GST proteins are a frequent feature of many human cancers. Recent evidence has revealed that the biology of most GST proteins is complex and multifaceted and that these proteins actively participate in tumorigenic processes such as cell survival, cell proliferation, and drug resistance. Structural and pharmacological studies have identified various GST inhibitors, and these molecules have progressed to clinical trials for the treatment of cancer and other diseases. In this review, we discuss recent findings in GST protein biology and their roles in cancer development, their contribution in chemoresistance, and the development of GST inhibitors for cancer treatment.

New quinoxaline compounds as DPP-4 inhibitors and hypoglycemics: design, synthesis, computational and bio-distribution studies

The current work represents the design and synthetic approaches of a new set of compounds 6–10 bearing the 1,4-dimethyl-2,3-dioxo-1,2,3,4-tetrahydroquinoxaline-6-sulfonamide scaffold. The biological evaluation revealed that most of the new compounds were promising selective dipeptidyl peptidase-IV (DPP-4) inhibitors and in vivo hypoglycemic agents utilizing linagliptin as a standard drug. The acute toxicity examination confirmed the safety profile of all compounds. Molecular docking studies related the significant DPP-4 suppression activity of compounds 9a, 10a, 10f, 10g to their nice fitting in the active pocket of DPP-4. In addition, the molecular dynamic study exhibited the stability of both 10a and 10g within the active site of DPP-4. The QSAR study showed that the difference between the predicted activities is very close to the experimental suppression effect. Moreover, both compounds 10a and 10g obeyed Lipinski's rule, indicating their efficient oral bioavailability. Compound 10a was radiolabeled, forming the ¹³¹I-SQ compound 10a to study the pharmacokinetic profile of this set of compounds. The biodistribution pattern hit the target protein since the tracer accumulated mainly in the visceral organs where DPP-4 is secreted in a high-level, thus with consequent stimulation of insulin secretion, leading to the target hypoglycemic effect.

The current work represents the design and synthetic approaches of a new set of compounds 6–10 bearing the 1,4-dimethyl-2,3-dioxo-1,2,3,4-tetrahydroquinoxaline-6-sulfonamide scaffold.

Design, synthesis, biological evaluation, QSAR analysis and molecular modelling of new thiazol-benzimidazoles as EGFR inhibitors

Heterocyclic rings such as thiazole and benzimidazole are considered as privileged structures, since they constitute several FDA-approved drugs for cancer treatment. In this work, a new set of 2-(2-(substituted) hydrazinyl)-4-(1-methyl-1H-benzo[d]imidazol-2-yl) thiazoles 4a-q were designed as epidermal growth factor receptor (EGFR) inhibitors and synthesized using concise synthetic methods. The new target compounds have been evaluated in vitro for their suppression activity against EGFR TK. Compounds 4n, 4h, 4i, 4a and 4d exhibited significant potency in comparison with erlotinib which served as a reference drug (IC50, 71.67-152.59 nM; IC50 erlotinib, 152.59 nM). Furthermore, MTT assay revealed that compounds 4j, 4a, 4f, 4h, 4n produced the most promising cytotoxic potency against the human breast cancer cell line (MCF-7) (IC50; 5.96-11.91 µM; IC50 erlotinib; 4.15 µM). Compound 4a showed promising activity as EGFR TK inhibitor as well as anti-breast cancer agent. In addition, 4a induced apoptotic effect and cell cycle arrest at G2/M phase preventing the mitotic cycle in MCF-7 cells. Moreover, 4a upregulated the oncogenic parameters; caspase-3, p53, Bax/Bcl-2 as well as it inhibited the level of PARP-1 enzyme. QSAR study was carried out for the new derivatives and it revealed the goodness of the models. Furthermore, molecular docking studies represented the binding modes of the promising compounds in the active pocket of EGFR.

A Comparative Study of the Anticancer Activity and PARP-1 Inhibiting Effect of Benzofuran-Pyrazole Scaffold and Its Nano-Sized Particles in Human Breast Cancer Cells

Breast cancer is considered the most common and deadly cancer among women worldwide. Nanomedicine has become extremely attractive in the field of cancer treatment. Due to the high surface to volume ratio and other unique properties, nanomaterials can be specifically targeted to certain cells and tissues to interact with the living systems. The strategic planning of this study is based on using the nanoprecipitation method to prepare nanoparticles BZP-NPs (3.8-5.7 nm) of the previously prepared benzofuran-pyrazole compound (IV) BZP which showed promising cytotoxic activity. The capacity of BZP and BZP-NPs to suppress the growth of human breast tumor MCF-7 and MDA-MB-231 cells was evaluated using MTT assay. The IC50 doses of BZP and BZP-NPs targeting normal breast cells MCF-12A exceeded those targeting the cancer cells by >1000-fold, demonstrating their reasonable safety profiles in normal cells. Furthermore, cell cycle analysis, apoptosis induction detection, assessment of p53, Bcl-2, caspase-3, and PARP-1 levels of BZP and its nano-sized-BZP-NPs particles were also evaluated. Although the obtained results were in the favor of compound IV in its normal-sized particles, BZP-NPs appeared as a hit compound which showed improved cytotoxicity against the tested human breast cancer cells associated with the induction of pre-G1 apoptosis as well as cell cycle arrest at G2/M phase. The increase in caspase-3 level, upregulation of p53, and downregulation of Bcl-2 protein expression levels confirmed apoptosis. Furthermore, ELISA results exhibited that BZP-NPs produced a more favorable impact as a PARP-1 enzyme inhibitor than the parent BZP.