Molecular diversity of trimethoxyphenyl-1,2,3-triazole hybrids as novel colchicine site tubulin polymerization inhibitors

Recent advances in the development of P2Y14R inhibitors: a patent and literature review (2018-present)

INTRODUCTION

The P2Y14 receptor (P2Y14R), a member of the G protein-coupled receptor family, is activated by extracellular nucleotides. Due to its involvement in inflammatory, immunological and other associated processes, P2Y14R has emerged as a promising therapeutic target. Despite lacking a determined three-dimensional crystal structure, the homology modeling technique based on closely related P2Y receptors' crystallography has been extensively utilized for developing active compounds targeting P2Y14R. Recent discoveries have unveiled numerous highly effective and subtype-specific P2Y14R inhibitors. This study presents an overview of the latest advancements in P2Y14R inhibitors.

AREAS COVERED

This review presents an overview of the advancements in P2Y14R inhibitor research over the past five years, encompassing new patents, journal articles, and highlighting the therapeutic prospects inherent in these compounds.

EXPERT OPINION

The recent revelation of the vast potential of P2Y14R inhibitors has led to the development of novel compounds that exhibit promising capabilities for the treatment of sterile inflammation of the kidney, potentially diabetes, and asthma. Despite being a relatively nascent class of compounds, certain members have already exhibited their capacity to surmount specific challenges posed by conventional P2Y14R inhibitors. Targeting P2Y14R through small molecules may present a promising therapeutic strategy for effectively managing diverse inflammatory diseases.

Structural modification strategies of triazoles in anticancer drug development

The triazole functional group plays a pivotal role in the composition of biomolecules with potent anticancer activities, including numerous clinically approved drugs. The strategic utilization of the triazole fragment in the rational modification of lead compounds has demonstrated its ability to improve anticancer activities, enhance selectivity, optimize pharmacokinetic properties, and overcome resistance. There has been significant interest in triazole-containing hybrids in recent years due to their remarkable anticancer potential. However, previous reviews on triazoles in cancer treatment have failed to provide tailored design strategies specific to these compounds. Herein, we present an overview of design strategies encompassing a structure-modification approach for incorporating triazoles into hybrid molecules. This review offers valuable references and briefly introduces the synthesis of triazole derivatives, thereby paving the way for further research and advancements in the field of effective and targeted anticancer therapies.

Novel naphthoquinone-1H-1,2,3-triazole hybrids: Design, synthesis and evaluation as inductors of ROS-mediated apoptosis in the MCF-7 cells

The search for novel anticancer drugs is essential to expand treatment options, overcome drug resistance, reduce toxicity, promote innovation, and tackle the economic impact. The importance of these studies lies in their contribution to advancing cancer research and enhancing patient outcomes in the battle against cancer. Here, we developed new asymmetric hybrids containing two different naphthoquinones linked by a 1,2,3-1H-triazole nucleus, which are potential new drugs for cancer treatment. The antitumor activity of the novel compounds was tested using the breast cancer cell lines MCF-7 and MDA-MB-231, using the non-cancer cell line MCF10A as control. Our results showed that two out of twenty-two substances tested presented potential antitumor activity against the breast cancer cell lines. These potential drugs, named here 12g and 12h were effective in reducing cell viability and promoting cell death of the tumor cell lines, exhibiting minimal effects on the control cell line. The mechanism of action of the novel drugs was assessed revealing that both drugs increased reactive oxygen species production with consequent activation of the AMPK pathway. Therefore, we concluded that 12g and 12h are novel AMPK activators presenting selective antitumor effects.

Design, synthesis and biological evaluation of 1,2,3-triazole benzothiazole derivatives as tubulin polymerization inhibitors with potent anti-esophageal cancer activities

In this work, we utilized the molecular hybridization strategy to design and synthesize novel 1,2,3-triazole benzothiazole derivatives K1-26. The antiproliferative activities against MGC-803, Kyse30 and HCT-116 cells were explored, and their structure-activity relationship were preliminarily conducted and summarized. Among them, compound K18, exhibited the strongest proliferation inhibitory activity, with esophageal cancer cells Kyse30 and EC-109 being the most sensitive to its effects (IC50 values were 0.042 and 0.038 μM, respectively). Compound K18 effectively inhibited tubulin polymerization (IC50 = 0.446 μM), thereby hindering tubulin polymerize into filamentous microtubules in Kyse30 and EC-109 cells. Additionally, compound K18 induced the degradation of oncogenic protein YAP via the UPS pathway. Based on these dual molecular-level effects, compound K18 could induce G2/M phase arrest and cell apoptosis in Kyse30 and EC-109 cells, as well as regulate the expression levels of cell cycle and apoptosis-related proteins. In summary, our findings highlight a novel 1,2,3-triazole benzothiazole derivative K18, which possesses significant potential for treating esophageal cancers.

Discovery of novel coumarin-based derivatives as inhibitors of tubulin polymerization targeting the colchicine binding site with potent anti-gastric cancer activities

In this work, a series of novel coumarin-based derivatives were designed and synthesized as tubulin polymerization inhibitors targeting the colchicine binding site, and their antiproliferative activities against MGC-803, HCT-116 and KYSE30 cells were evaluated. Among them, the compound I-3 (MY-1442) bearing a 6-methoxy-1,2,3,4-tetrahydroquinoline group exhibited most potent inhibitory activities on MGC-803 (IC50 = 0.034 μM), HCT-116 (IC50 = 0.081 μM) and KYSE30 cells (IC50 = 0.19 μM). Further mechanism studies demonstrated that compound I-3 (MY-1442) could directly bind to the colchicine binding site of β-tubulin to inhibit tubulin polymerization and microtubules at the cellular level. The results of molecular docking indicated there were well binding interactions between compound I-3 (MY-1442) and the colchicine binding site of β-tubulin. Compound I-3 (MY-1442) also exhibited effective anti-proliferation, pro-apoptosis, and anti-migration abilities against gastric cancer cells MGC-803. Additionally, compound I-3 (MY-1442) could regulate the expression of cell cycle- and apoptosis-related proteins. Importantly, compound I-3 (MY-1442) could significantly inhibit tumor growth in the MGC-803 xenograft tumor model with a TGI rate of 65.5 % at 30 mg/kg/day. Taken together, this work suggested that the coumarin skeleton exhibited great potential to be a key pharmacophore of tubulin polymerization inhibitors for the discovery of anticancer agents.

Latest developments in coumarin-based anticancer agents: mechanism of action and structure-activity relationship studies

Many researchers around the world are working on the development of novel anticancer drugs with different mechanisms of action. In this case, coumarin is a highly promising pharmacophore for the development of novel anticancer drugs. Besides, the hybridization of this moiety with other anticancer pharmacophores has emerged as a potent breakthrough in the treatment of cancer to decrease its side effects and increase its efficiency. This review aims to provide a comprehensive overview of the recent development of coumarin derivatives and their application as novel anticancer drugs. Herein, we highlight and describe the largest number of research works reported in this field from 2015 to August 2023, along with their mechanisms of action and structure-activity relationship studies, making this review different from the other review articles published on this topic to date.

Design and synthesis of cabotegravir derivatives bearing 1,2,3-triazole and evaluation of anti-liver cancer activity

Based on the structure of the anti-HIV drug cabotegravir, we introduced 1,2,3-triazole groups with different substituents to obtain 19 cabotegravir derivatives and tested their activity against HepG2 cells. The proliferation of HepG2 cells was examined following treatment with derivatives. Most of the compounds demonstrated significant inhibitory effects, particularly compounds KJ-5 and KJ-12 with IC50 values of 4.29 ± 0.10 and 4.07 ± 0.09 μM, respectively. Furthermore, both compounds 5 and 12 significantly caused cell apoptosis, G2/M arrest, and DNA damage, and suppressed invasion and migration in a concentration-dependent manner. In addition, KJ-5 and KJ-12 could trigger apoptosis via the mitochondrial pathway by increasing the ratio of Bax/Bcl-2 and activating cleaved caspase-9, cleaved caspase-3, and cleaved PARP.

Tubulin degradation: Principles, agents, and applications

The microtubule system plays an important role in the mitosis and growth of eukaryotic cells, and it is considered as an appealing and highly successful molecular target for cancer treatment. In fact, microtubule targeting agents, such as paclitaxel and vinblastine, have been approved by FDA for tumor therapy, which have achieved significant therapeutic effects and sales performance. At present, microtubule targeting agents mainly include microtubule-destabilizing agents, microtubule-stabilizing agents, and a few tubulin degradation agents. Although there are few reports about tubulin degradation agents at present, tubulin degradation agents show great potential in overcoming multidrug resistance and reducing neurotoxicity. In addition, some natural drugs could specifically degrade tubulin in tumor cells, but have no effect in normal cells, thus showing a good biosafety profile. Therefore, tubulin degradation agents might exhibit a better application. Currently, some small molecules have been designed to promote tubulin degradation with potent antiproliferative activities, showing the potential for cancer treatment. In this work, we reviewed the reports on tubulin degradation, and focused on the degradation mechanism and important functional groups of chemically synthesized compounds, hoping to provide help for the degradation design of tubulin.

Recent Advances in the Green Synthesis of Active N-Heterocycles and Their Biological Activities

N-heterocyclic scaffolds represent a privileged architecture in the process of drug design and development. It has widespread occurrence in synthetic and natural products, either those that are established or progressing as potent drug candidates. Additionally, numerous novel N-heterocyclic analogues with remarkable physiological significance and extended pharmaceutical applications are escalating progressively. Hence, the classical synthetic protocols need to be improvised according to modern requirements for efficient and eco-friendly approaches. Numerous methodologies and technologies emerged to address the green and sustainable production of various pharmaceutically and medicinally important N-heterocyclic compounds in last few years. In this context, the current review unveils greener alternatives for direct access to categorically differentiated N-heterocyclic derivatives and its application in the establishment of biologically active potent molecules for drug design. The green and sustainable methods accentuated in this review includes microwave-assisted reactions, solvent-free approaches, heterogeneous catalysis, ultrasound reactions, and biocatalysis.

Synthesis and bioactive evaluation of N-((1-methyl-1H-indol-3-yl)methyl)-N-(3,4,5-trimethoxyphenyl)acetamide derivatives as agents for inhibiting tubulin polymerization

Based on the inhibitory effect of CA-4 analogues and indoles on tubulin polymerization, we designed and synthesized a series of N-((1-methyl-1H-indol-3-yl)methyl)-2-(1H-pyrazol-1-yl or triazolyl)-N-(3,4,5-trimethoxyphenyl)acetamides. All the synthesized compounds were evaluated for their in vitro antiproliferative activities against HeLa, MCF-7 and HT-29 cancer cell lines, and some of the target compounds demonstrated effective activities towards the three tumour cell lines. Among them, compound 7d exhibited the most potent activities against HeLa (IC50 = 0.52 μM), MCF-7 (IC50 = 0.34 μM) and HT-29 (IC50 = 0.86 μM). Mechanistic studies revealed that compound 7d induced cell apoptosis in a dose-dependent manner, arrested the cells in the G2/M phase and inhibited polymerization of tubulin via a consistent way with colchicine. Therefore, 7d is a potential agent for the further development of tubulin polymerization inhibitors.

Discovery of dual tubulin-NEDDylation inhibitors with antiproliferative activity

Although various dual-target tubulin inhibitors have been designed and synthesised, no dual tubulin-NEDDylation inhibitors as antiproliferative agents were reported so far. In this work, a series of trimethoxyphenyl analogues as potential dual tubulin-NEDDylation inhibitors were synthesised and evaluated for their antiproliferative activity. Among them, compound C11 exhibited the most potent inhibitory activity with IC₅₀ values of 1.17, 2.48, and 1.47 μM against HepG2, PC3, and MCF7 cells, respectively. In addition, it displayed the potent inhibitory activity against tubulin with an IC₅₀ value of 2.40 μM and obviously inhibited tubulin polymerisation in HepG2 cells. Furthermore, C11 inhibited NEDDylation by a ATP-dependent manner. Molecular docking studies revealed that the methoxy group and dithiocarbamate group of C11 could form hydrogen bonds with residues of tubulin and E1 NEDD8-activating enzyme (NAE). These results suggested that compound C11 was a dual tubulin-NEDDylation inhibitor with antiproliferative activity.

An update on the recent advances and discovery of novel tubulin colchicine binding inhibitors

Microtubules, formed by α- and β-tubulin heterodimer, are considered as a major target to prevent the proliferation of tumor cells. Microtubule-targeted agents have become increasingly effective anticancer drugs. However, due to the relatively sophisticated chemical structure of taxane and vinblastine, their application has faced numerous obstacles. Conversely, the structure of colchicine binding site inhibitors (CBSIs) is much easier to be modified. Moreover, CBSIs have strong antiproliferative effect on multidrug-resistant tumor cells and have become the mainstream research orientation of microtubule-targeted agents. This review focuses mainly on the recent advances of CBSIs during 2017-2022, attempts to depict their biological activities to analyze the structure-activity relationships and offers new perspectives for designing next generation of novel CBSIs.

Regulated cell death (RCD) in cancer: key pathways and targeted therapies

Regulated cell death (RCD), also well-known as programmed cell death (PCD), refers to the form of cell death that can be regulated by a variety of biomacromolecules, which is distinctive from accidental cell death (ACD). Accumulating evidence has revealed that RCD subroutines are the key features of tumorigenesis, which may ultimately lead to the establishment of different potential therapeutic strategies. Hitherto, targeting the subroutines of RCD with pharmacological small-molecule compounds has been emerging as a promising therapeutic avenue, which has rapidly progressed in many types of human cancers. Thus, in this review, we focus on summarizing not only the key apoptotic and autophagy-dependent cell death signaling pathways, but the crucial pathways of other RCD subroutines, including necroptosis, pyroptosis, ferroptosis, parthanatos, entosis, NETosis and lysosome-dependent cell death (LCD) in cancer. Moreover, we further discuss the current situation of several small-molecule compounds targeting the different RCD subroutines to improve cancer treatment, such as single-target, dual or multiple-target small-molecule compounds, drug combinations, and some new emerging therapeutic strategies that would together shed new light on future directions to attack cancer cell vulnerabilities with small-molecule drugs targeting RCD for therapeutic purposes.

LSD1 inhibitors for anticancer therapy: a patent review (2017-present)

INTRODUCTION

Lysine-specific demethylase 1 (LSD1), which belongs to the demethylase of non-histone proteins, is believed to promote cancer cell proliferation and metastasis by modifying histones. LSD1 dysfunction may play a key role in a variety of cancers, such as acute myeloid leukemia and non-small cell lung cancer, indicating that LSD1 is a promising epigenetic target for cancer therapy. Many different types of small molecule LSD1 inhibitors have been developed and shown to inhibit tumor cell proliferation, invasion, and migration, providing a new treatment strategy for solid tumors.

AREAS COVERED

This review summarizes the progress of LSD1 inhibitor research in the last four years, including selected new patents and article publications, as well as the therapeutic potential of these compounds.

EXPERT OPINION

Natural products offer a promising prospect for developing novel potent LSD1 inhibitors, as structural design and activity of irreversible and reversible inhibitors have been continuously optimized since the discovery of the LSD1 target in 2004. The use of "microtubule-binding agents" and "dual-agent combination" has recently become a new anticancer technique, reducing the resistance and adverse reactions of traditional drugs. Several microtubule-binding drugs have been used successfully in clinical practice, providing structural scaffolds and new ideas for the development of safer drugs.

Designing and development of phthalimides as potent anti-tubulin hybrid molecules against malaria

Constant emergence of drug-resistant Plasmodium falciparum warrants urgent need for effective and inexpensive drugs. Herein, phthalimide (Pht) analogs possessing the bioactive scaffolds, benzimidazole and 1,2,3-triazole, were evaluated for in vitro and in vivo anti-plasmodial activity without any apparent hemolysis, or cytotoxicity. Analogs 4(a-e) inhibited the growth of 3D7 and RKL-9 strains at submicromolar concentrations. Defects were observed during parasite egress from or invasion of the red blood cells. Mitochondrial membrane depolarization was measured as one of the causes of cell death. Phts 4(a-e) in combination with artemisinin exhibited two-to three-fold increased efficacy. Biophysical and biochemical analysis suggest that Pht analogs mediate plasmodial growth inhibition by interacting with tubulin protein of the parasite. Lastly, Phts 4(a-e) significantly decreased parasitemia and extended host survival in murine model Plasmodium berghei ANKA infection. Combined, the data indicate that Pht analogs should be further explored, which could offer novel value to the antimalarial drug development pipeline.

BP-M345, a New Diarylpentanoid with Promising Antimitotic Activity

Previously, we reported the in vitro growth inhibitory effect of diarylpentanoid BP-M345 on human cancer cells. Nevertheless, at that time, the cellular mechanism through which BP-M345 exerts its growth inhibitory effect remained to be explored. In the present work, we report its mechanism of action on cancer cells. The compound exhibits a potent tumor growth inhibitory activity with high selectivity index. Mechanistically, it induces perturbation of the spindles through microtubule instability. As a consequence, treated cells exhibit irreversible defects in chromosome congression during mitosis, which induce a prolonged spindle assembly checkpoint-dependent mitotic arrest, followed by massive apoptosis, as revealed by live cell imaging. Collectively, the results indicate that the diarylpentanoid BP-M345 exerts its antiproliferative activity by inhibiting mitosis through microtubule perturbation and causing cancer cell death, thereby highlighting its potential as antitumor agent.

Click Chemistry in Natural Product Modification

Click chemistry is perhaps the most powerful synthetic toolbox that can efficiently access the molecular diversity and unique functions of complex natural products up to now. It enables the ready synthesis of diverse sets of natural product derivatives either for the optimization of their drawbacks or for the construction of natural product-like drug screening libraries. This paper showcases the state-of-the-art development of click chemistry in natural product modification and summarizes the pharmacological activities of the active derivatives as well as the mechanism of action. The aim of this paper is to gain a deep understanding of the fruitful achievements and to provide perspectives, trends, and directions regarding further research in natural product medicinal chemistry.

Synthesis and Antiproliferative Evaluation of 3-Chloroazetidin-2-ones with Antimitotic Activity: Heterocyclic Bridged Analogues of Combretastatin A-4

Antimitotic drugs that target tubulin are among the most widely used chemotherapeutic agents; however, the development of multidrug resistance has limited their clinical activity. We report the synthesis and biological properties of a series of novel 3-chloro-β-lactams and 3,3-dichloro-β-lactams (2-azetidinones) that are structurally related to the tubulin polymerisation inhibitor and vascular targeting agent, Combretastatin A-4. These compounds were evaluated as potential tubulin polymerisation inhibitors and for their antiproliferative effects in breast cancer cells. A number of the compounds showed potent activity in MCF-7 breast cancer cells, e.g., compound 10n (3-chloro-4-(3-hydroxy-4-methoxy-phenyl)-1-(3,4,5-trimethoxyphenyl)azetidin-2-one) and compound 11n (3,3-dichloro-4-(3-hydroxy-4-methoxyphenyl)-1-(3,4,5-trimethoxyphenyl)-azetidin-2-one), with IC₅₀ values of 17 and 31 nM, respectively, and displayed comparable cellular effects to those of Combretastatin A-4. Compound 10n demonstrated minimal cytotoxicity against non-tumorigenic HEK-293T cells and inhibited the in vitro polymerisation of tubulin with significant G₂/M phase cell cycle arrest. Immunofluorescence staining of MCF-7 cells confirmed that β-lactam 10n caused a mitotic catastrophe by targeting tubulin. In addition, compound 10n promoted apoptosis by regulating the expression of pro-apoptotic protein BAX and anti-apoptotic proteins Bcl-2 and Mcl-1. Molecular docking was used to explore the potential molecular interactions between novel 3-chloro-β-lactams and the amino acid residues of the colchicine binding active site cavity of β-tubulin. Collectively, these results suggest that 3-chloro-2-azetidinones, such as compound 10n, could be promising lead compounds for further clinical anti-cancer drug development.

1,2,3-Triazole hybrids as anticancer agents: A review

Despite the advancements in the development of anticancer agents, more effective and safer anticancer drugs still need to be developed as the current agents cause unwanted side effects and many patients have become drug resistant. 1,2,3-Triazoles, due to their remarkable biological potential, have received considerable attention in drug discovery for the development of anticancer agents. The present review article presents an overview of the recent advances in 1,2,3-triazole hybrids with anticancer potential over the last 2 years, their chemical structures, structure-activity relationships, and mechanisms of action, as well as insights into the docking studies.

WITHDRAWN: Discovery of indoline derivatives as anticancer agents via inhibition of tubulin polymerization

Human esophageal squamous cell carcinoma (ESCC) is one of the most lethal cancers in human digestive system. It is necessary to discover novel antitumor agents for the treatment of esophageal cancers because of its poor prognosis. Indoline has been reported as an efficient anticancer fragment to design novel anticancer agents. In this work, indoline derivatives were designed, synthesized and explored their anticancer activity. Compound 9d, which exhibited potent antiproliferative activity with IC50 values of 1.84 μM (MGC-803 cells), 6.82 μM (A549 cells), 1.61 μM (Kyse30 cells), 1.49 μM (Kyse450 cells), 2.08 μM (Kyse510 cells) and 2.24 μM (EC-109 cells), respectively. The most active compound 9d was identified as a tubulin inhibitor targeting colchicine binding site with an IC50 value of 3.4 µM. Compound 9d could strongly suppress the tubulin polymerization in Kyse450 cells. The results of molecular docking also suggested compound 9d could tightly bind into the colchicine binding site of β-tubulin. Besides, compound 9d inhibited the growth of KYSE450 cells in time and dose-dependent manners. All the results suggest that the indoline derivatives might be a class of novel tubulin inhibitors with potential anticancer activity and is worthy of further study.

Discovery of Novel Diarylamide N-Containing Heterocyclic Derivatives as New Tubulin Polymerization Inhibitors with Anti-Cancer Activity

Tubulin has been regarded as an attractive and successful molecular target in cancer therapy and drug discovery. Vicinal diaryl is a simple scaffold found in many colchicine site tubulin inhibitors, which is also an important pharmacophoric point of tubulin binding and anti-cancer activity. As the continuation of our research work on colchicine binding site tubulin inhibitors, we designed and synthesized a series of diarylamide N-containing heterocyclic derivatives by the combination of vicinal diaryl core and N-containing heterocyclic skeletons into one hybrid though proper linkers. Among of these compounds, compound 15b containing a 5-methoxyindole group exhibited the most potent inhibitory activity against the tested three human cancer cell lines (MGC-803, PC-3 and EC-109) with IC₅₀ values of 1.56 μM, 3.56 μM and 14.5 μM, respectively. Besides, the SARs of these compounds were preliminarily studied and summarized. The most active compound 15b produced the inhibition of tubulin polymerization in a dose-dependent manner and caused microtubule network disruption in MGC-803 cells. Therefore, compound 15b was identified as a novel tubulin polymerization inhibitor targeting the colchicine binding site. In addition, the results of molecular docking also suggested compound 15b could tightly bind into the colchicine binding site of β-tubulin.

Discovery of indoline derivatives as anticancer agents via inhibition of tubulin polymerization

Human esophageal squamous cell carcinoma (ESCC) is one of the most lethal cancers in human digestive system. It is necessary to discover novel antitumor agents for the treatment of esophageal cancers because of its poor prognosis. Indoline has been reported as an efficient anticancer fragment to design novel anticancer agents. In this work, indoline derivatives were designed, synthesized and explored their anticancer activity. Compound 9d, which exhibited potent antiproliferative activity with IC50 values of 1.84 μM (MGC-803 cells), 6.82 μM (A549 cells), 1.61 μM (Kyse30 cells), 1.49 μM (Kyse450 cells), 2.08 μM (Kyse510 cells) and 2.24 μM (EC-109 cells), respectively. The most active compound 9d was identified as a tubulin inhibitor targeting colchicine binding site with an IC50 value of 3.4 µM. Compound 9d could strongly suppress the tubulin polymerization in Kyse450 cells. The results of molecular docking also suggested compound 9d could tightly bind into the colchicine binding site of tubulin. Besides, compound 9d inhibited the growth of KYSE450 cells in a time and dose-dependent manner. All the results suggest that the indoline derivatives may be a class of novel tubulin inhibitors with potential anticancer activity, and which is worthy of further study.

Structural insights of oxindole based kinase inhibitors as anticancer agents: Recent advances

Small-molecule kinase inhibitors are being continuously explored as new anticancer therapeutics. Kinases are the phosphorylating enzymes which regulate numerous cellular functions such as proliferation, differentiation, migration, metabolism, and angiogenesis by activating several signalling pathways. Kinases have also been frequently found to be deregulated and overexpressed in cancerous tissues. Therefore, modulating the kinase activity by employing small molecules has emerged as a strategic approach for cancer treatment. On the other hand, oxindole motifs have surfaced as privileged scaffolds with significant multi-kinase inhibitory activity. The present review summarises recent advances in the development of oxindole based kinase inhibitors. The role of distinguished structural frameworks of oxindoles, such as 3-alkenyl oxindoles, spirooxindoles, 3-iminooxindoles and similar hydrazone derivatives have been described based on their kinase inhibition potential. Furthermore, the design strategies, mechanism of actions, structure activity relationships (SARs) and their mode of interaction with target protein have been critically highlighted.

Discovery of an orally active antitumor agent that induces apoptosis and suppresses EMT through heat shock protein 90 inhibition

Background Nowadays, lung cancer seriously affects human health in the world. Therefore, it is of great significance to develop effective anti-lung cancer drugs. Methods In this work, chalcone derivative HYQ97 was designed via a molecular hybridization strategy. It was synthesized by the cycloaddition in the presence of sodium ascorbate under mild conditions. Lung cancer cell lines were cultured to investigate its antitumor effects in vitro and in vivo. Results HYQ97 inhibited the proliferation of lung cancer cell lines. Specifically, its IC₅₀ value against lung cancer A549 cells was 74.26 nM. It could inhibit heat shock protein 90 (Hsp90) and degrade its client proteins in a dose-dependent manner. Furthermore, HYQ97 suppressed the epithelial mesenchymal transition process and induced apoptosis of A549 cells. Importantly, HYQ97 also had significant inhibitory effects on tumor growth in vivo. Conclusions Chalcone derivative HYQ97 is a promising candidate for lung cancer treatment.

Novel piperidine derivatives as colchicine binding site inhibitors induce apoptosis and inhibit epithelial-mesenchymal transition against prostate cancer PC3 cells

Tubulin polymerisation inhibitors that target colchicine binding site were powerful anticancer agents. Although along the years many colchicine binding site inhibitors (CBSIs) have been reported, few piperidine derivatives were identified as CBSIs. In this regard, we focussed efforts on the piperidine as a promising chemotype to develop potent CBSIs. Herein, novel piperidine derivatives were synthesised and evaluated for their antiproliferative activities. Among them, compound 17a displayed powerful anticancer activity with the IC₅₀ value of 0.81 µM against PC3 cells, which was significantly better than 5-fluorouracil. It could inhibit tubulin polymerisation binding at the colchicine site and inhibit the tumour growth in vitro and in vivo. Further biological studies depicted that 17a suppressed the colony formation, induced apoptosis, and inhibited epithelial-mesenchymal transition against PC3 cells. These results revealed that compound 17a is a promising colchicine binding site inhibitor for the treatment of cancer and it is worthy of further exploitation.

Annual review of LSD1/KDM1A inhibitors in 2020

Lysine-specific demethylase 1 (LSD1/KDM1A) has emerged as a promising target for the discovery of specific inhibitors as antitumor drugs. Based on the source of compounds, all LSD1 inhibitors in this review are divided into two categories: natural LSD1 inhibitors and synthetic LSD1 inhibitors. This review highlights the research progress of LSD1 inhibitors with the potential to treat cancer covering articles published in 2020. Design strategies, structure-activity relationships, co-crystal structure analysis and action mechanisms are also highlighted.

Tubulin Inhibitors Binding to Colchicine-Site: A Review from 2015 to 2019

Due to the three domains of the colchicine-site which is conducive to the combination with small molecule compounds, colchicine-site on the tubulin has become a common target for antitumor drug development, and accordingly, a large number of tubulin inhibitors binding to the colchicine-site have been reported and evaluated over the past years. In this study, tubulin inhibitors targeting the colchicine-site and their application as antitumor agents were reviewed based on the literature from 2015 to 2019. Tubulin inhibitors were classified into ten categories according to the structural features, including colchicine derivatives, CA-4 analogs, chalcone analogs, coumarin analogs, indole hybrids, quinoline and quinazoline analogs, lignan and podophyllotoxin derivatives, phenothiazine analogs, N-heterocycle hybrids and others. Most of them displayed potent antitumor activity, including antiproliferative effects against Multi-Drug-Resistant (MDR) cell lines and antivascular properties, both in vitro and in vivo. In this review, the design, synthesis and the analysis of the structure-activity relationship of tubulin inhibitors targeting the colchicine-site were described in detail. In addition, multi-target inhibitors, anti-MDR compounds, and inhibitors bearing antitumor activity in vivo are further listed in tables to present a clear picture of potent tubulin inhibitors, which could be beneficial for medicinal chemistry researchers.

Progress of tubulin polymerization activity detection methods

Tubulin, an important target in tumor therapy, is one of the hotspots in the field of antineoplastic drugs in recent years, and it is of great significance to design and screen new inhibitors for this target. Natural products and chemical synthetic drugs are the main sources of tubulin inhibitors. However, due to the variety of compound structure types, it has always been difficult for researchers to screen out polymerization inhibitors with simple operation, high efficiency and low cost. A large number of articles have reported the screening methods of tubulin inhibitors and their biological activity. In this article, the biological activity detection methods of tubulin polymerization inhibitors are reviewed. Thus, it provides a theoretical basis for the further study of tubulin polymerization inhibitors and the selection of methods for tubulin inhibitors.

Ni(ii), Cu(ii) and Zn(ii) complexes with the 1-trifluoroethoxyl-2,9,10-trimethoxy-7-oxoaporphine ligand simultaneously target microtubules and mitochondria for cancer therapy

Complexes 1–3 display potent anticancer activity against T-24 cell by disrupting mitochondria and microtubules. Furthermore, complex 1 exhibits almost same tumor growth inhibition activity in T-24 xenograft mouse model as cisplatin and paclitaxel.

Antiproliferative benzothiazoles incorporating a trimethoxyphenyl scaffold as novel colchicine site tubulin polymerisation inhibitors

Tubulin polymerisation inhibitors exhibited an important role in the treatment of patients with prostate cancer. Herein, we reported the medicinal chemistry efforts leading to a new series of benzothiazoles by a bioisosterism approach. Biological testing revealed that compound 12a could significantly inhibit in vitro tubulin polymerisation of a concentration dependent manner, with an IC₅₀ value of 2.87 μM. Immunofluorescence and EBI competition assay investigated that compound 12a effectively inhibited tubulin polymerisation and directly bound to the colchicine-binding site of β-tubulin in PC3 cells. Docking analysis showed that 12a formed hydrogen bonds with residues Tyr357, Ala247 and Val353 of tubulin. Importantly, it displayed the promising antiproliferative ability against C42B, LNCAP, 22RV1 and PC3 cells with IC₅₀ values of 2.81 μM, 4.31 μM, 2.13 μM and 2.04 μM, respectively. In summary, compound 12a was a novel colchicine site tubulin polymerisation inhibitor with potential to treat prostate cancer.

Discovery of oxyepiberberine as a novel tubulin polymerization inhibitor and an anti-colon cancer agent against LS-1034 cells

Coptis chinensis Franch. has been extensively used in traditional Chinese medicine. The chemical structure of oxyepiberberine, as an alkaloid isolated from Coptis chinensis Franch., has been previously studied. However, anti-cancer effects and underlying mechanisms of oxyepiberberine need to be explored. This study aimed to investigate the anti-cancer effects and underlying mechanisms of oxyepiberberine on LS-1034 human colon cancer cells. The anti-proliferative effects of six derivatives of oxyepiberberine on colon cancer cells were assessed. Among six derivatives, oxyepiberberine showed the greatest anti-proliferative effect on LS-1034 cells with an IC₅₀ value of 1.36 μM. Oxyepiberberine also induced apoptosis and inhibited migration of LS-1034 cells in a concentration-dependent manner. Importantly, oxyepiberberine was identified as a potent tubulin polymerization inhibitor. The tubulin polymerization inhibitory effects of oxyepiberberine in a concentration-dependent manner with an IC₅₀ value of 1.26 μM were observed. A xenograft mouse model of colon cancer showed that oxyepiberberine could suppress tumor growth without an obvious toxicity. Conclusion Oxyepiberberine was found as a novel tubulin polymerization inhibitor, and it could be a promising agent to treat colon cancer.

Discovery of tertiary amide derivatives incorporating benzothiazole moiety as anti-gastric cancer agents in vitro via inhibiting tubulin polymerization and activating the Hippo signaling pathway

On the basis and continuation of our previous studies on anti-tubulin and anti-gastric cancer agents, novel tertiary amide derivatives incorporating benzothiazole moiety were synthesized and the antiproliferative activity was studied in vitro. Preliminary structure activity relationships (SARs) were explored according to the in vitro antiproliferative activity results. Some of compounds could significantly inhibit the proliferation of three cancer cells (HCT-116, MGC-803 and PC-3 cells) and compound F10 exhibited excellent antiproliferative activity against HCT-116 cells (IC₅₀ = 0.182 μM), MGC-803 cells (IC₅₀ = 0.035 μM), PC-3 cells(IC₅₀ = 2.11 μM) and SGC-7901 cells (IC₅₀ = 0.049 μM). Compound F10 effectively inhibited tubulin polymerization (IC₅₀ = 1.9 μM) and bound to colchicine binding site of tubulin. Molecular docking results suggested compound F10 could bind tightly into the colchicine binding site of β-tubulin. Moreover, compound F10 could regulate the Hippo/YAP signaling pathway. Compound F10 activated Hippo signaling pathway from its very beginning MST1/2, as the result of Hippo cascade activation YAP were inhibited. And then it led to a decrease of c-Myc and Bcl-2 expression. Further molecular experiments showed that compound F10 arrested at G2/M phase, inhibited cell colony formatting and induced extrinsic and intrinsic apoptosis in MGC-803 and SGC-7901 cells. Collectively, compound F10 was the first to be reported as a new anticancer agent in vitro via inhibiting tubulin polymerization and activating the Hippo signaling pathway.

A Review on Recent Advances in Nitrogen-Containing Molecules and Their Biological Applications

The analogs of nitrogen-based heterocycles occupy an exclusive position as a valuable source of therapeutic agents in medicinal chemistry. More than 75% of drugs approved by the FDA and currently available in the market are nitrogen-containing heterocyclic moieties. In the forthcoming decade, a much greater share of new nitrogen-based pharmaceuticals is anticipated. Many new nitrogen-based heterocycles have been designed. The number of novel N-heterocyclic moieties with significant physiological properties and promising applications in medicinal chemistry is ever-growing. In this review, we consolidate the recent advances on novel nitrogen-containing heterocycles and their distinct biological activities, reported over the past one year (2019 to early 2020). This review highlights the trends in the use of nitrogen-based moieties in drug design and the development of different potent and competent candidates against various diseases.

Discovery of novel tertiary amide derivatives as NEDDylation pathway activators to inhibit the tumor progression in vitro and in vivo

NEDDylation pathway regulates multiple physiological process, unlike inhibitors, NEDDylation activators are rarely studied. Novel amide derivatives were synthesized and evaluated for antiproliferative activity against MGC803, MCF-7 and PC-3 cells. Among them, Ⅶ-31 displayed the most potent activity with an IC₅₀ value of 94 nmol/L against MGC803 cells. Cellular mechanisms elucidated that Ⅶ-31 inhibited the cell viability, arrested cell cycle at G2/M phase and induced apoptosis via intrinsic and extrinsic pathways against MGC803 cells. In addition, Ⅶ-31 activated NAE1-Ubc12-Cullin1 NEDDylation via interacting with NAE1 directly. Furthermore, the activation of NEDDylation resulted in the degradation of inhibitor of apoptosis proteins (IAPs). Importantly, Ⅶ-31 inhibited tumor growth in xenograft models in vivo without the apparent toxicity. In summary, it is the first time to reveal that Ⅶ-31 deserves consideration for cancer therapy as a NEDDylation activator.

Novel tertiary sulfonamide derivatives containing benzimidazole moiety as potent anti-gastric cancer agents: Design, synthesis and SAR studies

With the expectation to find out new anti-gastric cancer agents with high efficacy and selectivity, a series of novel tertiary sulfonamide derivatives were synthesized and the anti-cancer activity was studied in three selected cancer cell lines (MGC-803, PC-3, MCF-7) in vitro. Some of the synthesized compounds could significantly inhibit the proliferation of these tested cancer cells and were more potent than the positive control (5-Fu). The structure-activity relationship of tertiary sulfonamide derivatives was explored in this report. Among the tested compounds, compound 13g containing benzimidazole moiety showed the best anti-proliferation activities against MGC-803 cells (IC₅₀ = 1.02 μM), HGC-27 cells (IC₅₀ = 1.61 μM), SGC-7901 (IC₅₀ = 2.30 μM) cells as well as the good selectivity between the cancer and normal cells. Cellular mechanism studies elucidated compound 13g inhibited the colony formation of gastric cancer cell lines. Meanwhile, compound 13g arrested cell cycle at G2/M phase and induced cell apoptosis. Mechanistically, compound 13g markedly decreased p-Akt and p-c-Raf expression, which revealed that compound 13g targeted gastric cancer cell lines via interfering with AKT/mTOR and RAS/Raf/MEK/ERK pathways. All the findings suggest that compound 13g might be a valuable lead compound for the anti-gastric cancer agents.

1,2,3-Triazole-containing hybrids as potential anticancer agents: Current developments, action mechanisms and structure-activity relationships

Anticancer agents are critical for the cancer treatment, but side effects and the drug resistance associated with the currently used anticancer agents create an urgent need to explore novel drugs with low side effects and high efficacy. 1,2,3-Triazole is privileged building block in the discovery of new anticancer agents, and some of its derivatives have already been applied in clinics or under clinical trials for fighting against cancers. Hybrid molecules occupy an important position in cancer control, and hybridization of 1,2,3-triazole framework with other anticancer pharmacophores may provide valuable therapeutic intervention for the treatment of cancer, especially drug-resistant cancer. This review emphasizes the recent advances in 1,2,3-triazole-containing hybrids with anticancer potential, covering articles published between 2015 and 2019, and the structure-activity relationships, together with mechanisms of action are also discussed.

Structure-Based Pharmacophore Design and Virtual Screening for Novel Tubulin Inhibitors with Potential Anticancer Activity

Tubulin inhibitors have been considered as potential drugs for cancer therapy. However, their drug resistance and serious side-effects are the main reasons for clinical treatment failure. Therefore, there is still an urgent need to develop effective therapeutic drugs. Herein, a structure-based pharmacophore model was developed based on the co-crystallized structures of the tubulin with a high resolution. The model including one hydrogen-bond acceptor feature, two aromatic features, and one hydrophobic feature was further validated using the Gunner-Henry score method. Virtual screening was performed by an integrated protocol that combines drug-likeness analysis, pharmacophore mapping, and molecular docking approaches. Finally, five hits were selected for biological evaluation. The results indicated that all these hits at the concentration of 40 μM showed an inhibition of more than 50% against five human tumor cells (MCF-7, U87MG, HCT-116, MDA-MB-231, and HepG2). Particularly, hit 1 effectively inhibited the proliferation of these tumor cells, with inhibition rates of more than 80%. The results of tubulin polymerization and colchicine-site competition assays suggested that hit 1 significantly inhibited tubulin polymerization by binding to the colchicine site. Thus, hit 1 could be used as a potential chemotherapeutic agent for cancer treatment. This work also demonstrated the potential of our screening protocol to identify biologically active compounds.

Coumarin-containing hybrids and their anticancer activities

Cancer is the second leading cause of death worldwide, and it results in around 9 million deaths annually. The anticancer agents play an intriguing role in the treatment of cancers, while the severe anticancer scenario and the emergence of drug-resistant especially multidrug-resistant cancers create a huge demand for novel anticancer drugs with different mechanisms of action. The coumarin scaffold is ubiquitous in nature and is a highly privileged motif for the development of novel drugs due to its biodiversity and versatility. Coumarin derivatives can exert diverse antiproliferative mechanisms, and some of them such as Irosustat are under clinical trials for the treatment of various cancers, revealing their potential as putative anticancer drugs. Hybridization of coumarin moiety with other anticancer pharmacophores is a promising strategy to reduce side effects, overcome the drug resistance, and may provide valuable therapeutic intervention for the treatment of cancers. Thus, coumarin-containing hybrids occupy an important position in the development of novel anticancer agents. This review aims to summarize the recent advances made towards the development of coumarin-containing hybrids as potential anticancer agents, covering articles published between 2015 and 2019, and the structure-activity relationship together with mechanisms of action are also discussed.

Design, synthesis and antibacterial activity evaluation of moxifloxacin-amide-1,2,3-triazole-isatin hybrids

In this work, a series of novel moxifloxacin-amide-1,2,3-triazole-isatin hybrids 7a-l were designed and synthesized. The in vitro antibacterial activity against a panel of clinically important Gram-positive and Gram-negative bacteria including drug-resistant pathogens was also evaluated. All hybrids showed considerable activity against the tested pathogens with MIC values of ≤0.03 to 128 μg/mL, and some of them such as hybrids 7e, 7g and 7j were comparable to or better than the parent moxifloxacin (MIC: ≤0.03-8 μg/mL). Moreover, hybrids 7e, 7g and 7j also demonstrated low cytotoxicity towards CHO cells. However, the in vivo pharmacokinetic profiles of these three hybrids were generally far inferior to the parent moxifloxacin. The structure-activity relationship and structure-cytotoxicity relationship were also studied and discussed which may help with the identification of new chemical entities as potent antibacterial agents.