Discovery of 4-alkoxy-2-aryl-6,7-dimethoxyquinolines as a new class of topoisomerase I inhibitors endowed with potent in vitro anticancer activity

Design and synthesis of novel 2-S-alkylated Quinazolinones as dual BRAFV600E and EGFR inhibitors in melanoma: Mechanistic insights from apoptosis and cell cycle modulation

Melanoma, an aggressive and highly metastatic form of skin cancer, remains challenging to treat due to its resistance to conventional therapies and frequent mutations in the BRAF signaling pathway. In this study, we report the design and synthesis of a novel series of thirteen quinazolinone derivatives, featuring a phenyl thiazole moiety linked via a triazole acetamide spacer. These compounds were developed as potential dual inhibitors of BRAFV600E and EGFR, which should offer a promising therapeutic strategy for melanoma treatment. The antiproliferative activity of these compounds was evaluated against the NCI-60 cell line panel, with six compounds advancing to a five-dose screening. Three compounds, 7k, 7l, and 7m, exhibited broad-spectrum anticancer activity, with mean growth inhibition (GI%) exceeding 100 %. Compound 7l demonstrated exceptional efficacy against melanoma subpanels (GI% = 152 %) and potent dual kinase inhibition, with IC50 values of 0.048 μM against B-RAFV600E and 0.037 μM against EGFR. In vitro studies of compound 7l revealed significant cytotoxicity against MALME-3 M (IC50 = 3.16 μM) and LOX-IMVI (IC50 = 2.50 μM) melanoma cell lines, with minimal toxicity towards normal Vero cells. Cell cycle analysis showed G1-phase arrest and disrupted DNA synthesis in melanoma cells, while apoptosis assays demonstrated a dramatic increase in early apoptotic cells from 7.28 % to 40.69 %. Compound 7l modulated key apoptotic markers, increasing the BAX/Bcl-2 ratio by 14.42-fold and elevating caspase 3 and 9 levels, indicating its potential to overcome drug resistance and enhance therapeutic efficacy in melanoma treatment.

Diverse pharmacological activities of β-carbolines: Substitution patterns, SARs and mechanisms of action

β-Carbolines, a class of indole-containing heterocyclic alkaloids, are widely distributed in nature and possess diverse bioactivities, making them promising drug candidates against a wide range of diseases. The remarkable medicinal potential of β-carbolines has spurred the pharmaceutical research community to study their derivatives extensively. This review updates the development of β-carboline derivatives in recent years (2015-2024), particularly with a focus on their anticancer, antiparasitic, antimicrobial, antiviral, and neuroprotective properties, based on the modification approaches such as substitution on indole N (ring B), pyridine or its reduced forms (ring C), and dimerization of β-carbolines. Moreover, the mechanisms of action and structure-activity relationships of these β-carboline derivatives are highlighted to offer valuable insights on the design and development of new β-carbolines with better pharmacological activities.

Design, synthesis, and molecular dynamics-driven evaluation of quinoline-sulfonamide derivatives as potent and selective EGFR inhibitors with promising anti-cancer efficacy and safety profiles

The creation of new molecules that target EGFR is essential for the progression of cancer treatment. This study synthesized and evaluated 16 quinoline-sulfonamide derivatives for their potential as anti-cancer agents. Compound 8c, which contains a methoxy group on the benzenesulfonamide tail, exhibited notable EGFR inhibitory activity (IC50 = 0.161 µM), similar to that of Erlotinib (IC50 = 0.142 µM). Compound 8c demonstrated enhanced in-vitro cytotoxicity against HCT-116, MCF-7, HeLa, and HepG2 cancer cell lines. Studies on the cell cycle and apoptosis demonstrated that compound 8c caused G1/S arrest and markedly enhanced apoptosis in HepG2 cells. In-vivo, compound 8c demonstrated comparable and/or superior efficacy compared to doxorubicin in decreasing tumor volume, weight, TNF-alpha, and COX-2 levels in the SEC model, alongside improved histopathological and immunohistochemical results. Molecular docking and dynamic simulations confirmed its stable binding to EGFR, exhibiting superior stability metrics in comparison to Erlotinib. Pharmacokinetic and toxicity evaluations indicated that compound 8c exhibits favorable drug-like properties and a safer toxicity profile. These findings identify compound 8c as a potential candidate for the development of safe and effective anti-cancer therapies, necessitating additional preclinical investigations.

New 5, 6, 7, 8-Tetrahydro-Isoquinolines Bearing 2-Nitrophenyl Group Targeting RET Enzyme: Synthesis, Anticancer Activity, Apoptotic Induction and Cell Cycle Arrest

In this work, we synthesized new 5, 6, 7, 8-tetrahydroisoquinolines and 6, 7, 8, 9-tetrahydrothieno[2, 3-c]isoquinolines derivatives, and the structures of these new compounds were confirmed with different spectroscopic techniques. Furthermore, the anticancer activities of these compounds were assessed against eight tumor cell lines and one normal human skin fibroblast cell line (HSF). Subsequently, IC50 values of the synthesized compounds were determined for two specific cancer cell lines. Compound 3 exhibited the most potent antiproliferative activity against the HEPG2 cell line, whereas compound 9c demonstrated superior efficacy against the HCT116 cell line. Moreover, the mechanism of action for compound 3 on HEPG2 cells using flow cytometry and Annexin V-FITC apoptosis analysis was studied. Compound 3 caused cell cycle arrest at the G2/M with a 50-fold increase in apoptosis of the HEPG2 cell line. Finally, a molecular docking study was conducted to assess the inhibitory potential of compounds 3 and 7 against the RET enzyme. Results indicated that compounds 3 and 7 bind to the RET enzyme with binding energies of -5.2 and -5.6 kcal/mol, respectively. Although these values suggest inhibitory activity, they are less potent than the standard inhibitor, alectinib, which exhibits a binding energy of -7.2 kcal/mol.

Quinoline-linked 1,2,3-Triazole Hybrids: Design, Synthesis, Anticancer Activity and Computational Investigations

Synthesized a library of new quinoline-based 1,2,3-triazole scaffolds involving Suzuki-Miyaura cross-coupling and metal-free multicomponent reactions. Evaluated their in vitro anticancer activities against human breast (MCF-7), lung (A-549) and liver (HepG2) cancer cell lines with reference to Doxorubicin as standard. Four compounds 5a, 5d, 5e and 5f displayed outstanding activity against all three cell lines. Compound 5a, showcasing -Cl in the R2 position of the phenyl ring demonstrated potent activity with IC50 values of 9.25 ± 0.22, 9.56 ± 0.19 and 10.56 ± 0.19 µM against MCF-7, A-549 and HepG2 cell lines respectively. The compound 5f, containing m-Cl and m-OMe groups in R1 and R2 positions demonstrated potent activity with IC50 values of 10.49 ± 0.31 (MCF-7), 10.27 ± 0.27 (A-549) and 11.27 ± 0.30 µM (HepG2). Compound 5f with -Cl and -I group presented potent activity with an IC50 value of 11.40 ± 0.29 (MCF-7), 10.42 ± 0.21 (A-549) and 12.32 ± 0.33 µM (HepG2). Compound 5d gave out a potent activity with IC50 values of 10.42 ± 0.25 (MCF-7), 12.97 ± 0.22 (A-549) and 13.05 ± 0.45 µM (HepG2). Toxicity results against Hek-293 proved that these compounds were not harmful. The computational screening of these compounds revealed favourable drug-likeness properties and important binding interactions against Fibroblast Growth Factor Receptor 1.

Novel Anti-Tumor Effect of Natural Products from Aloe vera Resin and their In-Vitro/In-Silico Targeting Mechanism of Carbonic Anhydrase-II and IX

Human carbonic anhydrase (hCA) plays a vital role in the development and progression of tumors in hypoxic conditions. Herein we report the hCA-II and hCA-IX activities of natural products isolated from Aloe vera (L.) Burm.f., to know their potential in tumors. These isolated compounds (1-10) displayed varying degrees of inhibition against hCA-II and hCA-IX. All the compounds showed potent activity against hCA-IX with IC50 values in the range of 2.9-29.1 μM. While for hCA-II, compounds 1, 2, 5-10 exhibited IC50 in the range of 4.7-23.4 μM. The most effective hCA IX and II inhibitors, 2 and 5, were chosen for in vitro mechanism studies, revealing that they are competitive inhibitors. Furthermore, when tested for their cytotoxic effect on BJ (normal) cell line, all the compounds showed no cytotoxic behavior, while on Prostate cancer cells (PC-3), compounds 1, 3, 5, 7, and 9 exhibited significant antiproliferative activity. Molecular docking was also conducted within the hCA IX and hCA-II active sites to observe their binding capability. Compounds 1, 5, 7, and 9 were active against both isozymes of hCA and in the PC-3 cell line, therefore these are the best choices for further in vivo studies.

New tetrahydroisoquinolines bearing nitrophenyl group targeting HSP90 and RET enzymes: synthesis, characterization and biological evaluation

In this study, new tetrahydroisoquinoline compounds were synthesized by reaction of 7-Acetyl-4-cyano-1,6-dimethyl-6-hydroxy-8- (3-nitrophenyl or 4-nitrophenyl)-5,6,7,8-tetrahydrosoquinoline-3(2H)-thiones with methyl iodide, chloro acetonitrile, ethyl chloroacetate to produce compounds 3-5 and reacted with N-arylchloroacetamides reagents to gave tetrahydroisoquinolin-3-ylthio) acetamides compounds 6a-c, 8a-b which can cyclized to 6,7,8,9-tetrahydrothieno[2,3-c]Isoquinoline-2-carboxamides compounds 7a-c, 9a-b. Also react with N-(benzthiazol-2-yl)-2-chloroacetamideto give compound 10. The structures of all newly synthesized compounds were characterized by elemental and spectral analyses. Also, most of the synthesized compounds were evaluated for their anticancer activities aganist MCF7 and HEPG2 cell lines. From the result we found that the most active compound against the MCF7 cell lines was compound 8b, and the most active compound against HEPG2 cell lines was compound 3. Then the effects of compound 3 on the HEPG2 cell line was investigated using an apoptotic Annexin V-FITC test and flow cytometry. Compound 3 induced a 59-fold increase in HEPG2 cell line apoptosis and cell cycle arrested at the G0-G1, G2/M phases. Moreover, the molecular docking study was applied and the result showed that compounds 8b bind to the RET enzyme with binding energies of - 6.8 kcal/mol in comparison with standard alectinib, which exhibits a binding energy of - 7.2 kcal/mol. Compound 3 can bind with HSP 90 with a binding energy (ΔG) of - 6.8 kcal/mol, which was comparable to the standard Onalespib (- 7.1 kcal/mol).

Design, synthesis, in vitro, and in silico studies of novel isatin-hybrid hydrazones as potential triple-negative breast cancer agents

Recent advances in cancer therapy have been made possible by monoclonal antibodies, domain antibodies, antibody drug conjugates, etc. The most impact has come from controlling cell cycle checkpoints through checkpoint inhibitors. This manuscript explores the potential of a series of novel N-benzyl isatin based hydrazones (5-25), which were synthesized and evaluated as anti-breast cancer agents. The synthesized hydrazones of N-benzyl isatin were screened in vitro against two cell lines, the MDA-MB-231 breast cancer cell line and the MCF-10A breast epithelial cell line. The results indicated that all compounds showed great potential against the triple-negative MDA-MB-231 breast cancer cell line. Compound 23 with nitro substitution at the 4th position of the phenyl ring exhibited significant antiproliferative potential for the MDA-MB-231 with an IC50 value of 15.8 ± 0.6 μM. Molecular dynamics and molecular docking simulations were performed to get a deeper understanding of the interactions between the synthesized compounds and cancer cells.

Novel NO-TZDs and trimethoxychalcone-based DHPMs: design, synthesis, and biological evaluation as potential VEGFR-2 inhibitors

Novel series of nitric oxide-releasing thiazolidine-2,4-diones (NO-TZD-3a-d,5,6) and 3,4,5-trimethoxychalcone-based multifunctional 1,4-dihydropyrimidines (CDHPM-10a-g) have been designed and synthesised as potent broad-spectrum anticancer agents with potential VEGFR-2 inhibition. The designed analogs were evaluated for their anticancer activities towards a full panel of NCI-60 tumour cell lines and CDHPM-10a-g emerged mean %inhibitions ranging from 76.40 to 147.69%. Among them, CDHPM-10e and CDHPM-10f demonstrated the highest MGI% of 147.69 and 140.24%, respectively. Compounds CDHPM-10a,b,d-f showed higher mean %inhibitory activity than the reference drug sorafenib (MGI% = 105.46%). Superiorly, the hybrid CDHPM-10e displayed the highest potencies towards all the herein tested subpanels of nine types of cancer with MGI50 of 1.83 µM. Also, it revealed potent cytostatic single-digit micromolar activity towards the herein examined cancer cell lines. The designed compounds CDHPM-10a-g were exposed as potent non-selective broad-spectrum anticancer agents over all NCI subpanels with an SI range of 0.66-1.97. In addition, the target analog CDHPM-10e revealed potency towards VEGFR-2 kinase comparable to that of sorafenib with a sub-micromolar IC50 value of 0.11 µM. Also, CDHPM-10e could effectively induce Sub-G1-phase arrest and prompt apoptosis via caspase and p53-dependent mechanisms. Furthermore, CDHPM-10e revealed significant anti-metastatic activity as detected by wound healing assay. The modelling study implies that CDHPM-10e overlaid well with sorafenib and formed a strong H-bond in the DFG binding domain. The ADMET studies hinted out that CDHPM-10e met Pfizer's drug-likeness criteria. The presented novel potent anticancer agent merits further devotion as a new lead product in developing more chalcone-based VEGFR-2 inhibitors.

Novel quinoline-4-carboxamide derivatives potentiates apoptosis by targeting PDK1 to overcome chemo-resistance in colorectal cancer: Theoretical and experimental results

A series of novel N,2-diphenyl-6-(aryl/heteroaryl)quinoline-4-carboxamide derivatives were designed and synthesized using the Suzuki coupling reaction and evaluated them for their anticancer activity. These compounds were screened for anti-colon cancer activity through in-silico studies by molecular docking and molecular dynamics studies. Furthermore, the density functional theory was used to determine the molecule's electrical properties. The molecular electrostatic potential map is used to evaluate the charge distribution on the molecule surface. Unveiling that the compound 7a (binding energy of -10.2 kcal/mol) has good inhibition activity compared to other synthesized compounds (7b-7j) as well as the standard drug Gefitinib. The stability of the compound 7a with the 1OKY protein was confirmed through molecular dynamics simulation studies, indicating potential anti-colon cancer activity against phosphoinositide dependent protein kinase-1 (PDK1). The in-silico ADMET pharmacokinetic properties indicate adherence to Lipinski's rule of five for favorable safety profiles and the compound falls within the optimal range for physicochemical and pharmacokinetic properties, which is comparable to that of the standard medication drug Gefitinib. The synthesized library of compounds was further evaluated for their in-vitro anticancer potency against colon, pancreatic and breast cancer cells. The results demonstrated that the compounds effectively suppressed the proliferative potential of the screened cells in a concentration-dependent manner, as revealed by MTT assay. The anticancer potential of these molecules was further evaluated by acridine orange/PI, and Hoechst/PI which demonstrates the potential of molecules to induce apoptosis in cancer cells. Further investigations and optimization of these derivatives could lead to the development of effective anticancer strategies.

Targeting focal adhesion kinase (FAK) in cancer therapy: A recent update on inhibitors and PROTAC degraders

Focal adhesion kinase (FAK) is considered as a pivotal intracellular non-receptor tyrosine kinase, and has garnered significant attention as a promising target for anticancer drug development. As of early 2024, a total of 12 drugs targeting FAK have been approved for clinical or preclinical studies worldwide, including three PROTAC degraders. In recent three years (2021-2023), significant progress has been made in designing targeted FAK anticancer agents, including the development of a novel benzenesulfofurazan type NO-releasing FAK inhibitor and the first-in-class dual-target inhibitors simultaneously targeting FAK and HDACs. Given the pivotal role of FAK in the discovery of anticancer drugs, as well as the notable advancements achieved in FAK inhibitors and PROTAC degraders in recent years, this review is underbaked to present a comprehensive overview of the function and structure of FAK. Additionally, the latest findings on the inhibitors and PROTAC degraders of FAK from the past three years, along with their optimization strategies and anticancer activities, were summarized, which might help to provide novel insights for the development of novel targeted FAK agents with promising anticancer potential and favorable pharmacological profiles.

Discovery of new quinoline derivatives bearing 1-aryl-1,2,3-triazole motif as influenza H1N1 virus neuraminidase inhibitors

Sporadically and periodically, influenza outbreaks threaten global health and the economy. Antigen drift-induced influenza virus mutations hamper antiviral drug development. Thus, a novel antiviral agent is urgently needed to address medication inefficacy issues. Herein, sixteen new quinoline-triazole hybrids 6a-h and 9a-h were prepared and evaluated in vitro against the H1N1 virus. In particular, 6d, 6e, and 9b showed promising H1N1 antiviral activity with selective index (SI) CC50/IC50 values of 15.8, 37, and 29.15. After that, the inhibition rates for various mechanisms of action (virus replication, adsorption, and virucidal activity) were investigated for the most efficient candidates 6d, 6e, and 9b. Additionally, their ability to inhibit neuraminidase was evaluated. With an IC50 value of 0.30 µM, hybrid 6d demonstrated effective and comparable inhibitory activity to Oseltamivir. Ultimately, molecular modeling investigations, encompassing molecular docking and molecular dynamic simulations, were conducted to provide a scientific basis for the observed antiviral results.

Coumarin as an Elite Scaffold in Anti-Breast Cancer Drug Development: Design Strategies, Mechanistic Insights, and Structure-Activity Relationships

Breast cancer is the most common cancer among women. Currently, it poses a significant threat to the healthcare system due to the emerging resistance and toxicity of available drug candidates in clinical practice, thus generating an urgent need for the development of new potent and safer anti-breast cancer drug candidates. Coumarin (chromone-2-one) is an elite ring system widely distributed among natural products and possesses a broad range of pharmacological properties. The unique distribution and pharmacological efficacy of coumarins attract natural product hunters, resulting in the identification of numerous natural coumarins from different natural sources in the last three decades, especially those with anti-breast cancer properties. Inspired by this, numerous synthetic derivatives based on coumarins have been developed by medicinal chemists all around the globe, showing promising anti-breast cancer efficacy. This review is primarily focused on the development of coumarin-inspired anti-breast cancer agents in the last three decades, especially highlighting design strategies, mechanistic insights, and their structure-activity relationship. Natural coumarins having anti-breast cancer efficacy are also briefly highlighted. This review will act as a guideline for researchers and medicinal chemists in designing optimum coumarin-based potent and safer anti-breast cancer agents.

Camptothecin structure simplification elaborated new imidazo[2,1-b]quinazoline derivative as a human topoisomerase I inhibitor with efficacy against bone cancer cells and colon adenocarcinoma

Camptothecin is a pentacyclic natural alkaloid that inhibits the hTop1 enzyme involved in DNA transcription and cancer cell growth. Camptothecin structure pitfalls prompted us to design new congeners using a structure simplification strategy to reduce the ring extension number from pentacyclic to tetracyclic while maintaining potential stacking of the new compounds with the DNA base pairs at the Top1-mediated cleavage complex and aqueous solubility, as well as minimizing compound-liver toxicity. The principal axis of this study was the verification of hTop1 inhibiting activity as a possible mechanism of action and the elaboration of new simplified inhibitors with improved pharmacodynamic and pharmacokinetic profiling using three structure panels (A-C) of (isoquinolinoimidazoquinazoline), (imidazoquinazoline), and (imidazoisoquinoline), respectively. DNA relaxation assay identified five compounds as hTop1 inhibitors belonging to the imidazoisoquinolines 3a,b, the imidazoquinazolines 12, and the isoquinolinoimidazoquinazolines 7a,b. In an MTT cytotoxicity assay against different cancer cell lines, compound 12 was the most potent against HOS bone cancer cells (IC50 = 1.47 μM). At the same time, the other inhibitors had no detectable activity against any cancer cell type. Compound (12) demonstrated great penetrating power in the HOS cancer cells' 3D-multicellular tumor spheroid model. Bioinformatics research of the hTop1 gene revealed that the TP53 cell proliferative gene is in the network of hTop1. The finding is confirmed empirically using the gene expression assay that proved the increase in p53 expression. The impact of structure simplification on compound 12 profile, characterized by the absence of acute oral liver toxicity when compared to Doxorubicin as a standard inhibitor, the lethal dose measured on Swiss Albino female mice and reported at LD50 = 250 mg/kg, and therapeutic significance in reducing colon adenocarcinoma tumor volume by 75.36 % after five weeks of treatment with compound 12. The molecular docking solutions of the active CPT-based derivative 12 and the inactive congener 14 into the active site of hTop1 and the activity cliffing of such MMP directed us to recommend the addition of HBD and HBA variables to compound 12 imidazoquinazoline core scaffold to enhance the potency via hydrogen bond formation with the major groove amino acids (Asp533, Lys532) as well as maintaining the hydrogen bond with the minor groove amino acid Arg364.

Novel Glu-based pyrazolo[3,4-d]pyrimidine analogues: design, synthesis and biological evaluation as DHFR and TS dual inhibitors

A novel series of multifunctional pyrazolo[3,4-d]pyrimidine-based glutamate analogs (6a-l and 7a,b) have been designed and synthesized as antifolate anticancer agents. Among the tested compounds, 6i exhibited the most potent anti-proliferative activity towards NSCLC, CNS, Ovarian, Prostate, Colon, Melanoma, Breast, and Renal cancers with good to weak cytostatic activity and non-lethal actions. 6i demonstrated higher selectivity for cancer than normal cells. 6i could significantly increase the accumulation of S-phase cells during the cell cycle distribution of cancer cells with high potency in the induction of apoptosis. The results unveiled that 6i probably acts through dual inhibition of DHFR and TS enzymes (IC₅₀ = 2.41 and 8.88 µM, correspondingly). Docking studies of 6i displayed that N1-p-bromophenyl and C3-Methyl groups participate in substantial hydrophobic interactions. The drug-likeness features inferred that 6i met the acceptance criteria of Pfizer. Taking together, 6i could be a promising prototype for further optimization as an effective anticancer drug.

Development of novel anilinoquinazoline-based carboxylic acids as non-classical carbonic anhydrase IX and XII inhibitors

As part of our ongoing endeavour to identify novel inhibitors of cancer-associated CA isoforms IX and XII as possible anticancer candidates, here we describe the design and synthesis of small library of 2-aryl-quinazolin-4-yl aminobenzoic acid derivatives (6a-c, 7a-c, and 8a-c) as new non-classical CA inhibitors. On account of its significance in the anticancer drug discovery and in the development of effective CAIs, the 4-anilinoquinazoline privileged scaffold was exploited in this study. Thereafter, the free carboxylic acid functionality was appended in the ortho (6a-c), meta (7a-c), or para-positon (8a-c) of the anilino motif to furnish the target inhibitors. All compounds were assessed for their inhibitory activities against the hCA I, II (cytosolic), IX, and XII (trans-membrane, tumour-associated) isoforms. Moreover, six quinazolines (6a-c, 7b, and 8a-b) were chosen by the NCI-USA for in vitro anti-proliferative activity evaluation against 59 human cancer cell lines representing nine tumour subpanels.

Discovery of indolinone-bearing benzenesulfonamides as new dual carbonic anhydrase and VEGFR-2 inhibitors possessing anticancer and pro-apoptotic properties

In the current medical era, the utilization of a single small molecule to simultaneously target two distinct molecular targets is emerging as a highly effective strategy in the battle against cancer. Carbonic Anhydrase (CA) and Vascular-Endothelial Growth Factor (VEGF) are genes that are activated in response to low oxygen levels (hypoxia) and play a role in the development and progression of tumors in hypoxic conditions. Herein we report the design, synthesis, and biological assessment of a series of novel indolinone-based benzenesulfonamides (8a-k, 11a-d, 15a-d, and 16) as potential dual inhibitors for cancer-associated hCA IX/XII and VEGFR-2. All the synthesized sulfonamides were assessed for their inhibitory effect against four CA isoforms I, II, IX, and XII where they displayed varying degrees of hCA inhibition. The most effective and selective hCA IX and XII inhibitors 8g, 8j and 15b were chosen to be tested for their in vitro inhibitory impact against VEGFR-2 as well as their antiproliferative impact against VEGFR-2 overexpressing MDA-MB-231 and MCF-7 breast cancer cells. Furthermore, molecular docking studies were conducted within the hCA IX, XII, and VEGFR-2 active sites to explain the observed inhibitory results.

Design and synthesis of 6-arylpyridine-tethered sulfonamides as novel selective inhibitors of carbonic anhydrase IX with promising antitumor features toward the human colorectal cancer

Hypoxia, a characteristic feature of solid tumors, develops as a result of excessive cell proliferation and rapid tumor growth exceeding the oxygen supply, and can result in angiogenesis activation, increased invasiveness, aggressiveness, and metastasis, leading to improved tumor survival and suppression of anticancer drug therapeutic impact. SLC-0111, a ureido benzenesulfonamide, is a selective human carbonic anhydrase (hCA) IX inhibitor in clinical trials for the treatment of hypoxic malignancies. Herein, we describe the design and synthesis of novel 6-arylpyridines 8a-l and 9a-d as structural analogues of SLC-0111, in the aim of exploring new selective inhibitors for the cancer-associated hCA IX isoform. The para-fluorophenyl tail in SLC-0111 was replaced by the privileged 6-arylpyridine motif. Moreover, both ortho- and meta-sulfonamide regioisomers, as well as an ethylene extended analogous were developed. All 6-arylpyridine-based SLC-0111 analogues were screened in vitro for their inhibitory potential against a panel of hCAs (hCA I, II, IV and IX isoforms) using stopped-flow CO₂ hydrase assay. In addition, the anticancer activity was firstly explored against a panel of 57 cancer cell lines at the USA NCI-Developmental Therapeutic Program. Compound 8g emerged as the best anti-proliferative candidate with mean GI% value equals 44. Accordingly, a cell viability assay (MTS) for 8g was applied on colorectal HCT-116 and HT-29 cancer cell lines as well as on the healthy HUVEC cells. Thereafter, Annexin V-FITC apoptosis detection, cell cycle, TUNEL, and qRT-PCR, colony formation, and wound healing assays were applied to gain mechanistic insights and to understand the behavior of colorectal cancer cells upon the treatment of compound 8g. Also, a molecular docking analysis was conducted to provide in silico insights into the reported hCA IX inhibitory activity and selectivity.

Molecular Target Interactions of Quinoline Derivatives as Anticancer Agents: A Review

One of the leading causes of death worldwide is cancer, which poses substantial risks to both society and an individual's life. Cancer therapy is still challenging, despite developments in the field and continued research into cancer prevention. The search for novel anticancer active agents with a broader cytotoxicity range is therefore continuously ongoing. The benzene ring gets fused to a pyridine ring at two carbon atoms close to one another to form the double ring structure of the heterocyclic aromatic nitrogen molecule known as quinoline (1-azanaphthalene). Quinoline derivatives contain a wide range of pharmacological activities, including antitubercular, antifungal, antibacterial, and antimalarial properties. Quinoline derivatives have also been shown to have anticancer properties. There are many quinoline derivatives widely available as anticancer drugs that act via a variety of mechanisms on various molecular targets, such as inhibition of topoisomerase, inhibition of tyrosine kinases, inhibition of heat shock protein 90 (Hsp90), inhibition of histone deacetylases (HDACs), inhibition of cell cycle arrest and apoptosis, and inhibition of tubulin polymerization.

2-Arylquinolines as novel anticancer agents with dual EGFR/FAK kinase inhibitory activity: synthesis, biological evaluation, and molecular modelling insights

In this study, different assortments of 2-arylquinolines and 2,6-diarylquinolines have been developed. Recently, we have developed a new series of 6,7-dimethoxy-4-alkoxy-2-arylquinolines as Topoisomerase I (TOP1) inhibitors with potent anticancer activity. Utilising the SAR outputs from this study, we tried to enhance anticancer and TOP1 inhibitory activities. Though target quinolines demonstrated potent antiproliferative effect, specifically against colorectal cancer DLD-1 and HCT-116, they showed weak TOP1 inhibition which may be attributable to their non-coplanarity. Thereafter, screening against kinase panel revealed their dual inhibitory activity against EGFR and FAK. Quinolines 6f, 6h, 6i, and 20f were the most potent EGFR inhibitors (IC50s = 25.39, 20.15, 22.36, and 24.81 nM, respectively). Meanwhile, quinolines 6f, 6h, 6i, 16d, and 20f exerted the best FAK inhibition (IC50s = 22.68, 14.25, 18.36, 17.36, and 15.36 nM, respectively). Finally, molecular modelling was employed to justify the promising EGFR/FAK inhibition. The study outcomes afforded the first reported quinolines with potent EGFR/FAK dual inhibition.

Design and synthesis of benzothiazole-based SLC-0111 analogues as new inhibitors for the cancer-associated carbonic anhydrase isoforms IX and XII

In this work, different series of benzothiazole-based sulphonamides 8a-c, 10, 12, 16a-b and carboxylic acids 14a-c were developed as novel SLC-0111 analogues with the goal of generating potent carbonic anhydrase (CA) inhibitors. The adopted strategy involved replacing the 4-fluorophenyl tail in SLC-0111 with a benzothiazole motif that attached to the ureido linker to produce compounds 8c and its regioisomers 8a-b. In addition, the ureido spacer was elongated by methylene or ethylene groups to afford the counterparts 10 and 12. In turn, the primary sulfamoyl zinc binding group (ZBG) was either substituted or replaced by carboxylic acid functionality in order to provide the secondary sulphonamide-based SLC-0111 analogues 16a-b, and the carboxylic acid derivatives 14a-c, respectively. All compounds (8a-c, 10, 12, 14a-c and 16a-b) were tested for their ability to inhibit CA isoforms CA I, II, IX and XII. Additionally, the in vitro anticancer properties of the developed CAIs were evaluated.

Piperazine tethered bergenin heterocyclic hybrids: design, synthesis, anticancer activity, and molecular docking studies

In an attempt to develop natural product-based anticancer agents, a series of novel piperazine-linked bergenin heterocyclic hybrids bearing arylthiazolyl (5a-e), benzothiazolyl (10a-i), and arylsulfonyl (13a-o) were synthesized using the classical Mannich reaction and evaluated for their anticancer activity. All the synthesized derivatives were assessed for in vitro cytotoxic activity against a panel of human cancer and normal cell lines and the results showed that most of the compounds exhibited significant cytotoxic activity against cancer cells and mild cytotoxicity against normal cells. In particular, the compounds 5a, 5c, 10f, and 13o showed potent cytotoxic activity against tongue and oral cancer cell lines compared to the parent compound (<100 μM). Considering the efficacy, the compounds 5a, 5c, 10f, and 13o were subjected to cell cycle analysis and the results indicated that the compounds mitigated the cell cycle progression at the G0/G1 phase in the tongue and oral cancer cell lines. Subsequently, the annexin V/PI staining assay demonstrated that the compounds 5a, 5c, 10f, and 13o induced early and late apoptosis against tongue cancer and necrosis against oral cancer. Further, gene expression analysis revealed that 5a, 5c, and 13o treatment regulated the BAX and BcL-2 expression and also the selected compounds significantly reduced the expression level of vimentin, oct-4, and nanog. In addition, molecular docking studies revealed that the selected derivatives have strong binding energy with the BcL2 protein and downregulates the expression. Taken together, the study results implied that these compounds are promising anticancer candidates by modulating the epithelial to mesenchymal transition axis and could be considered for further development of novel anticancer drugs.

New Potential Agents for Malignant Melanoma Treatment-Most Recent Studies 2020-2022

Malignant melanoma (MM) is the most lethal skin cancer. Despite a 4% reduction in mortality over the past few years, an increasing number of new diagnosed cases appear each year. Long-term therapy and the development of resistance to the drugs used drive the search for more and more new agents with anti-melanoma activity. This review focuses on the most recent synthesized anti-melanoma agents from 2020-2022. For selected agents, apart from the analysis of biological activity, the structure-activity relationship (SAR) is also discussed. To the best of our knowledge, the following literature review delivers the latest achievements in the field of new anti-melanoma agents.

Novel 3-(6-methylpyridin-2-yl)coumarin-based chalcones as selective inhibitors of cancer-related carbonic anhydrases IX and XII endowed with anti-proliferative activity

Carbonic anhydrases (CAs) are one of the promising targets for the development of anticancer agents. CA isoforms are implicated in various physiological processes and are expressed in both normal and cancerous cells. Thus, non-isoform selective inhibitors are associated with several side effects. Consequently, designing selective inhibitors towards cancer-related hCA IX/XII rather than the ubiquitous cytosolic isozymes hCA I and II is the main research objective in the field. Herein, a new series of 3-(6-methylpyridin-2-yl)coumarin derivatives 3 and 5a–o was designed and synthesised. The CA inhibition activities for the synthesised coumarins were analysed on isoforms hCA I, II, IX, and XII. Interestingly, both cancer-linked isoforms hCA IX/XII were inhibited by the prepared coumarins with inhibition constants ranging from sub- to low-micromolar range, whereas hCA I and II isoforms haven’t been inhibited up to 100 µM. Furthermore, the target coumarins were assessed for their antitumor activity on NCI-59 human cancer types.

Design and synthesis of Aza-boeravinone derivatives as potential novel topoisomerase I inhibitors

Based on the structural skeleton of natural products boeravinones, two types of 6H-chromeno[3,4-b]quinoline derivatives were designed and synthesized by nitrogen atom substitution strategy. Then, their cytotoxic activities were evaluated against six human tumor cell lines including HepG2 (hepatocellular carcinoma), A2780 (ovarian cancer), Hela (cervical cancer), HCT116 (colorectal cancer), SW1990 (pancreatic cancer), and MCF7 (breast cancer). The results showed that compounds ZML-8 and ZML-14 exhibited robust inhibitory activities against HepG2 cells with IC₅₀ values of 0.58 and 1.94 μM, respectively. In addition, ZML-8 and ZML-14 showed higher selectivity against HepG2 and L-02 cells than Topotecan. Mechanistically, ZML-8 and ZML-14 not only induced cell cycle arrest in the G2/M phase and cell apoptosis, but also dose-dependently inhibited topoisomerase I activity and induced DNA damage in HepG2 cells. Molecular docking showed that ZML-8 and ZML-14 could interact with topoisomerase I-DNA complex with a similar binding mode to Topotecan. Inhibitory activities of these two compounds on topoisomerase I were then confirmed in both cell-free systems and in whole-cell lysates. Taken together, compounds ZML-8 and ZML-14 merit further development as a new generation of non-camptothecin topoisomerase I inhibitors for the treatment of cancer.

Design, Synthesis, and Biological Evaluation of a Novel VEGFR-2 Inhibitor Based on a 1,2,5-Oxadiazole-2-Oxide Scaffold with MAPK Signaling Pathway Inhibition

Over the past few decades, the development of broad-spectrum anticancer agents with anti-angiogenic activity has witnessed considerable progress. In this study, a new series of pyrazolo[3,4-d]pyrimidines based on a phenylfuroxan scaffold were designed, synthesized, and evaluated, in terms of their anticancer activities. NCI-60 cell one-dose screening revealed that compounds 12a-c and 14a had the best MGI%, among the tested compounds. The target fluorinated compound 12b, as the most active one, showed better anticancer activity compared to the reference drug sorafenib, with IC50 values of 11.5, 11.6, and 13 µM against the HepG-2, A2780CP, and MDA-MB-231 cell lines, respectively. Furthermore, compound 12b (IC50 = 0.092 µM) had VEGFR-2-inhibitory activity comparable to that of the standard inhibitor sorafenib (IC50 = 0.049 µM). Furthermore, the ability of compound 12b in modulating MAPK signaling pathways was investigated. It was found to decrease the level of total ERK and its phosphorylated form, as well as leading to the down-regulation of metalloproteinase MMP-9 and the over-expression of p21 and p27, thus leading to subG1 cell-cycle arrest and, thus, the induction of apoptosis. Additionally, compound 12b decreased the rate of wound healing in the absence of serum, in comparison to DMSO-treated cells, providing a significant impact on metastasis inhibition. The quantitative RT-PCR results for E-cadherin and N-cadherin showed lower expression of the neuronal N-cadherin and increased expression of epithelial E-cadherin, indicating the ability of 12b to suppress metastasis. Furthermore, 12b-treated HepG2 cells expressed a low level of anti-apoptotic BCL-2 and over-expressed proapoptotic Bax genes, respectively. Using the DAF-FM DA fluorescence probe, compound 12b produced NO intracellularly as efficiently as the reference drug JS-K. In silico molecular docking studies showed a structural similarity through an overlay of 12b with sorafenib. Interestingly, the drug-likeness properties of compound 12b met the expectations of Pfizer's rule for the design of new drug candidates. Therefore, this study presents a novel anticancer lead compound that is worthy of further investigation and activity improvement.

Design, synthesis and anti-hepatocellular carcinoma activity of 3-arylisoquinoline alkaloids

This article describes the syntheses and biological activity of five 3-arylisoquinoline natural products corydamine (1), N-formyl Corydamine (2), hypecumine (3), Decumbenine B (XW) and 2-(1,3-dioxolo [4,5-h]isoquinolin-7-yl)-4,5-dimethoxy-N-methyl-Benzeneethanamine (A), and twelve analogues. Among them, 1, 2, and A were synthesized for the first time. In vitro screening for anti-proliferative activity showed that derivative 1a could significantly inhibit the proliferation of HCC cells (IC₅₀ = 9.82 μM on Huh7 cells and 6.83 μM on LM9 cells), and arrest cell cycle at G₂/M phase. The mechanistic studies further suggested compound 1a was a dual inhibitor of Topo I and Topo II, and Topo II inhibitory activity was superior to etoposide. In addition, 1a could significantly inhibit the invasion and migration of cancer cells by inhibiting the expression of MMP-9, and induce apoptosis through inhibiting the activation of the PI3K/Akt/mTOR signaling pathway. Moreover, in vivo studies demonstrated 1a could obviously reduce the growth of xenograft tumor and possessed good pharmacokinetic parameters, which indicated the potential value of 1a in treating liver cancer.

Novel Benzothiazole-Based Dual VEGFR-2/EGFR Inhibitors Targeting Breast and Liver Cancers: Synthesis, Cytotoxic Activity, QSAR and Molecular Docking Studies

A novel series of benzothiazole-based derivatives linked to various amino acids and their corresponding ethyl ester analogues were synthesized and were initially screened for their cytotoxic activity against human breast cancer cell line (MCF-7) and human liver carcinoma (HepG-2) and were further assessed as VEGFR-2 inhibitors. All the newly synthesized benzothiazole derivatives showed promising cytotoxic activities against the tested cell lines. Derivatives exhibited potent cytotoxic and VEGFR-2 inhibitory activities were then evaluated further as anticancer agents against the resistant triple-negative breast cancer (TNBC) cell line (MDA-MB-231) and as EGFR inhibitors. The carboxylic acid derivatives 10-12 and their ester analogues 21-23 displayed the highest anticancer activities with IC₅₀ of 0.73-0.89 µM, against MCF-7 and IC₅₀ of 2.54-2.80 µM, against HepG-2; compared to doxorubicin (IC₅₀ = 1.13 and 2.75 µM, respectively). In addition to their safety towards the normal cell line, the ethyl ester derivatives 21-23 showed a potent activity against the resistant MDA-MB-231 cell line with IC₅₀ of 5.45-7.28 µM, relative to doxorubicin (IC₅₀ = 7.46 µM) surpassing their carboxylic acid analogues 10-12 (IC₅₀ of 8.88-11.02 µM). Furthermore, the promising derivatives 10-12 and 21-23 displayed promising VEGFR-2 inhibitory activity (IC₅₀ = 0.15-0.19 µM) comparable to that of sorafenib (IC₅₀ = 0.12 µM). Against EGFR, the ethyl ester derivatives 21-23 showed superior inhibitory activity relative to the used reference standard, erlotinib, with IC₅₀ of 0.11-0.16 vs. 0.18 µM, respectively. The QSAR study revealed that the molecular bulkiness and molecular partial charge distribution govern the kinase inhibition potency in this series. Furthermore, the molecular docking study in VEGFR-2 active site showed that the newly synthesized benzothiazole derivatives adopted the common binding pattern of type II PK inhibitors.

One-pot three-component synthesis of novel pyrazolo[3,4-b]pyridines as potent antileukemic agents

In the current study, we report on the development of novel series of pyrazolo[3,4-b]pyridine derivatives (8a-u, 11a-n, and 14a,b) as potential anticancer agents. The prepared pyrazolo[3,4-b]pyridines have been screened for their antitumor activity in vitro at NCI-DTP. Thereafter, compound 8a was qualified by NCI for full panel five-dose assay to assess its GI₅₀, TGI and LC₅₀ values. Compound 8a showed broad-spectrum anti-proliferative activities over the whole NCI panel, with outstanding growth inhibition full panel GI₅₀ (MG-MID) value equals 2.16 μM and subpanel GI₅₀ (MG-MID) range: 1.92-2.86 μM. Furthermore, pyrazolo[3,4-b]pyridines 8a, 8e-h, 8o, 8u, 11a, 11e, 11h, 11l and 14a-b were assayed for their antiproliferative effect against a panel of leukemia cell lines (K562, MV4-11, CEM, RS4;11, ML-2 and KOPN-8) where they possessed moderate to excellent anti-leukemic activity. Moreover, pyrazolo[3,4-b]pyridines 8o, 8u, 14a and 14b were further explored for their effect on cell cycle on RS4;11 cells, in which they dose-dependently increased populations of cells in G2/M phases. Finally we analyzed the changes of selected proteins (HOXA9, MEIS1, PARP, BcL-2 and McL-1) related to cell death and viability in RS4;11 cells via Western blotting. Collectively, the obtained results suggested pyrazolo[3,4-b]pyridines 8o, 8u, 14a and 14b as promising lead molecules for further optimization to develop more potent and efficient anticancer candidates.

Design, synthesis, and molecular docking study of some 2-((7-chloroquinolin-4-yl) amino) benzohydrazide Schiff bases as potential Eg5 inhibitory agents

In Search of new microtubule-targeting compounds and to identify a promising Eg5 inhibitory agents, a series of 2-((7-chloroquinolin-4-yl) amino) benzohydrazide Schiff bases molecules (6 a-r) were synthesized using appropriate synthetic method. The synthesized compounds were characterized by using FTIR, Proton NMR, Carbon NMR and mass spectral analysis. All eighteen compounds were evaluated for their Eg5 inhibitory activity. Among the evaluated compounds, only seven compounds are shown inhibitory activity. The results of Steady state ATPase reveled that compounds 6b, 6l and 6p exhibited promising inhibitory activity with IC₅₀ Values of 2.720 ± 0.69, 2.676 ± 0.53 and 2.408 ± 0.46 respectively. Malachite Green Assay results reveled that 6q compound showed better inhibitory activity with IC₅₀ Value of 0.095 ± 0.27. In vitro antioxidant capacity of the synthesized compounds was investigated. A molecular docking studies were performed to evaluate interaction in to binding site of kinesin spindle protein, these interaction influencing may support Eg5 inhibitory activity. The drug like parameters of the eighteen synthesized compounds were also computed using Qikprop software. In conclusion, some of 2-((7-chloroquinolin-4-yl) amino) benzohydrazide Schiff base compounds represent promising drug like agents for discovery of effective anticancer molecules.

Treatment for liver cancer: From sorafenib to natural products

Liver cancer most commonly develops in patients with chronic liver disease, the etiology of which includes viral hepatitis (B and C), alcohol, obesity, dietary carcinogens, and so forth. The current treatment modalities, including surgical resection and liver transplantation, have been found far from effective. Hence, there is an obvious critical need to develop alternative strategies for the treatment of it. In this review, we discuss the formation process and therapeutic targets of liver cancer. Currently, targeted therapy is limited to sorafenib, lenvatinib, regorafenib, ramucirumab and cabozantinib which leads to a survival benefit in patients, but on the other hand is hampered by the occurrence of drug resistance. Pleasingly and importantly, there are multiple natural products undergoing clinical evaluation in liver cancer, such as polyphenols like icaritin, resveratrol, and silybin, saponins including ginsenoside Rg3 and glycyrrhizinate, alkaloid containing irinotecan and berberine and inorganic compound arsenic trioxide at present. Preclinical and clinical studies have shown that these compounds inhibit liver cancer formation owing to the influence on the anti-viral, anti-inflammation, anti-oxidant, anti-angiogenesis and anti-metastasis activity. Furthermore, a series of small molecule derivatives inspired by the aforementioned compounds are designed and synthesized according to structure-activity relationship studies. Drug combination and novel type of drug-targeted delivery system thereof have been well developed. This article is ended by a perspective remark of futuristic development of natural product-based therapeutic regimen for liver cancer treatment. We expect that this review is an account for current status of natural products as promising anti-liver cancer treatments and should contribute to its understanding.