Discovery of novel chalcone-dithiocarbamates as ROS-mediated apoptosis inducers by inhibiting catalase

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.

Trypanocidal potential of synthetic p-aminochalcones: In silico and in vitro evaluation

Chagas disease (CD) is a neglected tropical disease of worldwide health concern, caused by the flagellate protozoan Trypanosoma cruzi (T. cruzi), endemic in Latin America and present in North America and Europe. The WHO recommended drug for CD, benznidazole has low safety profile and several limitations. Therefore, an entity with better therapeutic potential to treat CD is required. Chalcones are an important class of compounds, which have shown antichagasic potential. Thus, the objective of this study was to evaluate the activity of synthetic p-aminochalcones against T. cruzi. Chalcones 1 and 2 were synthesized by Claisen-Schmidt condensation and characterized by both spectroscopic and theoretical methods. Initially, they were submitted to molecular docking simulations using cruzain and trypanothione reductase (TR) enzymes. It was expected to observe the possible interactions of chalcones with the catalytic site and other important regions of these main pharmacological targets of T. cruzi. Their cytotoxicity within host cells were assessed by MTT reduction assay using LLC-MK2 cells, with CC50 = 85.6 ± 9.2 µM and 1115 ± 381.7 µM for chalcones 1 and 2, respectively. These molecules were also tested against epimastigote and trypomastigote life forms of T. cruzi, causing reduction in the number of viable parasites. For the evaluation of the effect on intracellular amastigotes, infected LLC-MK2 cells were incubated with the chalcones for 24 h, causing reduction in the percentage of infected cells and the number of amastigotes/100 cells. Finally, flow cytometry assays were performed for analyzing cell death mechanisms (7-AAD/AxPE labelling), cytoplasmic ROS accumulation (DCFH-DA assay) and mitochondrial transmembrane potential disruption (Rho123 assay). Both chalcones (1 and 2) caused membrane damage, ROS accumulation and mitochondrial depolarization. In conclusion, the synthetic p-aminochalcones presented trypanocidal effect, causing membrane damage and oxidative stress. Their mechanism of action may be related to cruzain and TR inhibition.

Bacterial Tyrosinase Inhibition, Hemolytic and Thrombolytic Screening, and In Silico Modeling of Rationally Designed Tosyl Piperazine-Engrafted Dithiocarbamate Derivatives

Piperazine is a privileged moiety that is a structural part of many clinical drugs. Piperazine-based scaffolds have attracted the attention of pharmaceutical and medicinal scientists to develop novel, efficient therapeutic agents owing to their significant and promising biological profile. In the current study, an ecofriendly ultrasonic-assisted synthetic approach was applied to achieve a novel series of 1-tosyl piperazine dithiocarbamate acetamide hybrids 4a-4j, which was evaluated for in vitro tyrosinase inhibition and thrombolytic and hemolytic cytotoxic activities. Among all the piperazine-based dithiocarbamate acetamide target molecules 4a-4j, the structural analogs 4d displayed excellent tyrosinase inhibition efficacy (IC50 = 6.88 ± 0.11 µM) which was better than the reference standard drugs kojic acid (30.34 ± 0.75 µM) and ascorbic acid (11.5 ± 1.00 µM), respectively, which was further confirmed by in silico induced-fit docking (IFD) simulation Good tyrosinase activities were exhibited by 4g (IC50 = 7.24 ± 0.15 µM), 4b (IC50 = 8.01 ± 0.11 µM) and 4c (IC50 = 8.1 ± 0.30 µM) dithiocarbamate acetamides, which were also better tyrosinase inhibitors than the reference drugs but were less active than the 4d structural hybrid. All the derivatives are less toxic, having values in the 0.29 ± 0.01% to 15.6 ± 0.5% range. The scaffold 4b demonstrated better hemolytic potential (0.29 ± 0.01%), while a remarkably high thrombolytic chemotherapeutic potential was displayed by analog 4e (67.3 ± 0.2%).

A Mulberry Diels-Alder-Type Adduct, Kuwanon M, Triggers Apoptosis and Paraptosis of Lung Cancer Cells through Inducing Endoplasmic Reticulum Stress

The mulberry tree (Morus alba) has been cultivated in China for thousands of years. Mulberry Diels-Alder-type adducts (MDAAs) are characteristic constituents of the genus Morus. The unique structure and diverse bioactivities of MDAAs have attracted the attention of researchers. Kuwanon M (KWM) is an MDAA isolated from the root bark of Morus alba. This research reports the growth inhibitory effects of KWM on human lung cancer cells and its possible mechanism. In A549 and NCI-H292 cells, KWM treatment induced suppression of cell proliferation and migration. The appearance of chromatin condensation, phosphatidyl serine exposure and caspase cleavage indicated the arising of apoptosis. The loss of mitochondrial membrane potential (MMP), release of cytochrome c and dysregulation of Bax/Bcl-2 demonstrated that the KWM-induced apoptosis was through the mitochondrial pathway. Paraptosis was simultaneously detected under KWM treatment, as evidenced by the exhibition of cytoplasmic vacuolation, down-regulation of Alix and up-regulation of endoplasmic reticulum (ER) stress-related proteins. Mechanistically, ER stress induced activation of unfolded protein response (UPR) pathways and activation of the MAPK (JNK and ERK) pathway, all of which were critical for KWM-induced apoptosis and paraptosis. These findings suggested the possibility that KWM might be considered as a potential lung cancer therapeutic agent.

Chalcones: Promising therapeutic agents targeting key players and signaling pathways regulating the hallmarks of cancer

The need for innovative anticancer treatments with high effectiveness and low toxicity is urgent due to the development of malignancies that are resistant to chemotherapeutic agents and the poor specificity of existing anticancer treatments. Chalcones are 1,3-diaryl-2-propen-1-ones, which are the precursors for flavonoids and isoflavonoids. Chalcones are readily available from a wide range of natural resources and consist of very basic chemical scaffolds. Because the ease with which the synthesis it allows for the production of several chalcone derivatives. Various in-vitro and in-vivo studies indicate that naturally occurring and synthetic chalcone derivatives exhibit promising biological activities against cancer hallmarks such as proliferation, angiogenesis, invasion, metastasis, inflammation, stemness, and regulation of cancer epigenetics. According to their structure and functional groups, chalcones derivatives and their hybrid compounds exert a broad range of biological activities through targeting key elements and signaling molecules relevant to cancer progression. This review will provide valuable insights into the latest updates of chalcone groups as anticancer agents and extensively discuss their underlying molecular mechanisms of action.

Ultrasound-Assisted Synthesis and In Silico Modeling of Methanesulfonyl-Piperazine-Based Dithiocarbamates as Potential Anticancer, Thrombolytic, and Hemolytic Structural Motifs

Piperazine-based dithiocarbamates serve as important scaffolds for numerous pharmacologically active drugs. The current study investigates the design and synthesis of a series of dithiocarbamates with a piperazine unit as well as their biological activities. Under ultrasound conditions, the corresponding piperazine-1-carbodithioates 5a–5j were synthesized from monosubstituted piperazine 2 and N-phenylacetamides 4a–4j in the presence of sodium acetate and carbon disulfide in methanol. The structures of the newly synthesized piperazines were confirmed, and their anti-lung carcinoma effects were evaluated. A cytotoxic assay was performed to assess the hemolytic and thrombolytic potential of the synthesized piperazines 5a–5j. The types of substituents on the aryl ring were found to affect the anticancer activity of piperazines 5a–5j. Piperazines containing 2-chlorophenyl (5b; cell viability = 25.11 ± 2.49) and 2,4-dimethylphenyl (5i; cell viability = 25.31 ± 3.62) moieties demonstrated the most potent antiproliferative activity. On the other hand, piperazines containing 3,4-dichlorophenyl (5d; 0.1%) and 3,4-dimethylphenyl (5j; 0.1%) rings demonstrated the least cytotoxicity. The piperazine with the 2,5-dimethoxyphenyl moiety (5h; 60.2%) showed the best thrombolytic effect. To determine the mode of binding, in silico modeling of the most potent piperazine (i.e., 5b) was performed, and the results were in accordance with those of antiproliferation. It exhibits a similar binding affinity to PQ10 and an efficient conformational alignment with the lipophilic site of PDE10A conserved for PQ10A.

Synthesis of novel antibacterial and antifungal dithiocarbamate-containing piperazine derivatives via re-engineering multicomponent approach

A metal-free multicomponent synthetic route for the diverse preparation of dithiocarbamate-containing piperazine derivatives was developed through the C-N bond cleavage of DABCO ring. This multicomponent re-engineering approach proceeds via the reaction of amines, CS2 and DABCO salts in one pot. Various DABCO salts and secondary amines are tolerated well in this protocol to afford a broad spectrum of dithiocarbamate-containing piperazines in good to high yields. Then, the selected compounds have been deployed against some critical types of bacteria and fungi. A certain number of synthesized compounds revealed not only appropriate antibacterial activity as investigated by disc fusion and minimum inhibitory concentration methods against bacteria (Gram-positive and Gram-negative), but also depicted good to excellent antifungal activity.

The Versatility in the Applications of Dithiocarbamates

Dithiocarbamate ligands have the ability to form stable complexes with transition metals, and this chelating ability has been utilized in numerous applications. The complexes have also been used to synthesize other useful compounds. Here, the up-to-date applications of dithiocarbamate ligands and complexes are extensively discussed. Some of these are their use as enzyme inhibitor and treatment of HIV and other diseases. The application as anticancer, antimicrobial, medical imaging and anti-inflammatory agents is examined. Moreover, the application in the industry as vulcanization accelerator, froth flotation collector, antifouling, coatings, lubricant additives and sensors is discussed. The various ways in which they have been employed in synthesis of other compounds are highlighted. Finally, the agricultural uses and remediation of heavy metals via dithiocarbamate compounds are comprehensively discussed.

Synthesis, Anticancer Assessment, and Molecular Docking of Novel Chalcone-Thienopyrimidine Derivatives in HepG2 and MCF-7 Cell Lines

Heterocycles containing thienopyrimidine moieties have attracted attention due to their interesting biological and pharmacological activities. In this research article, we reported the synthesis of a series of new hybrid molecules through merging the structural features of chalcones and pyridothienopyrimidinones. Our results indicated that the synthesis of chalcone-thienopyrimidine derivatives from the corresponding thienopyrimidine and chalcones proceeded in a relatively short reaction time with good yields and high purity. Most of these novel compounds exhibited moderate to robust cytotoxicity against HepG2 and MCF-7 cancer cells similar to that of 5-fluorouracil (5-FU). The results indicated that IC₅₀ of the two compounds (3b and 3g) showed more potent anticancer activities against HepG2 and MCF-7 than 5-FU. An MTT assay and flow cytometry showed that only 3b and 3g had anticancer activity and antiproliferative activities at the G1 phase against MCF-7 cells, while six compounds (3a-e and 3g) had cytotoxicity and cell cycle arrest at different phases against HepG2 cells. Their cytotoxicity was achieved through downregulation of Bcl-2 and upregulation of Bax, caspase-3, and caspase-9. Although all tested compounds increased oxidative stress via increment of MDA levels and decrement of glutathione reductase (GR) activities compared to control, the 3a, 3b, and 3g in HepG2 and 3b and 3g in MCF-7 achieved the target results. Moreover, there was a positive correlation between cytotoxic efficacy of the compound and apoptosis in both HepG2 (R ² = 0.531; P = 0.001) and MCF-7 (R ² = 0.219; P = 0.349) cell lines. The results of molecular docking analysis of 3a-g into the binding groove of Bcl-2 revealed relatively moderate binding free energies compared to the selective Bcl-2 inhibitor, DRO. Like venetoclax, compounds 3a-g showed 2 violations from Lipinski's rule. However, the results of the ADME study also revealed higher drug-likeness scores for compounds 3a-g than for venetoclax. In conclusion, the tested newly synthesized chalcone-pyridothienopyrimidinone derivatives showed promising antiproliferative and apoptotic effects. Mechanistically, the compounds increased ROS production with concomitant cell cycle arrest and apoptosis. Therefore, regulation of the cell cycle and apoptosis are possible targets for anticancer therapy. The tested compounds could be potent anticancer agents to be tested in future clinical trials after extensive pharmacodynamic, pharmacokinetic, and toxicity profile investigations.

Design, synthesis and evaluation of novel bis-substituted aromatic amide dithiocarbamate derivatives as colchicine site tubulin polymerization inhibitors with potent anticancer activities

As the continuation of our work on the development of tubulin inhibitors with potential anticancer activities, novel bis-substituted aromatic amide dithiocarbamate derivatives were designed by contacting bis-substituted aryl scaffolds (potential anti-tubulin fragments) with N-containing heterocycles (potential anti-tubulin fragments) in one hybrid using the anticancer dithioformate unit as the linker. The antiproliferative activity against three digestive tract tumor cells was evaluated and preliminary structure activity relationships were summarized. Among these compounds, compound 20q exhibited most potent antiproliferative activity against MGC-803, HCT-116, Kyse30 and Kyse450 cells with IC₅₀ values of 0.084, 0.227, 0.069 and 0.078 μM, respectively. In further studies, compound 20q was identified as a novel tubulin inhibitor targeting the colchicine binding site. Compound 20q could inhibit the microtubule assembly and disrupt cytoskeleton in Kyse30 and Kyse450 cells. The results of molecular docking suggested that compound 20q could tightly bind into the colchicine binding site of tubulin by hydrogen bonds and hydrophobic interactions. Compound 20q dose-dependently inhibited the cell growth and colony formation, effectively arrested cells at the G2/M phase and induce mitochondrial apoptosis in Kyse30 and Kyse450 cells. In addition, Compound 20q could regulate the expression of G2/M phase and mitochondrial apoptosis related proteins. Collectively, compound 20q was here reported as a novel tubulin inhibitor with potential anticancer activities.

Progress in the development of small molecular inhibitors of the Bruton's tyrosine kinase (BTK) as a promising cancer therapy

Bruton tyrosine kinase (BTK) is a key kinase in the B cell antigen receptor signal transduction pathway, which is involved in the regulation of the proliferation, differentiation and apoptosis of B cells. BTK has become a significant target for the treatment of hematological malignancies and autoimmune diseases. Ibrutinib, the first-generation BTK inhibitor, has made a great contribution to the treatment of B cell malignant tumors, but there are still some problems such as resistance or miss target of site mutation. Therefore, there is an imperative need to develop novel BTK inhibitors to overcome these problems. Besides, proteolysis targeting chimera (PROTAC) technology has been successfully applied to the development of BTK degradation agents, which has opened a fresh way for the BTK targeted treatment. This paper reviews the biological function of BTK, the discovery and development of BTK targeted drugs as a promising cancer therapy. It mainly reviews the binding sites and structural characteristics of BTK, structure-activity relationships, activity and drug resistance of BTK inhibitors, as well as potential treatment strategies to overcome the resistance of BTK, which provides a reference for the rational design and development of new powerful BTK inhibitors.

Synthesis and biological evaluation of 3,5-diaryl-pyrazole derivatives as potential antiprostate cancer agents

Prostate cancer is the most frequently diagnosed tumor in men and the second leading cause of cancer-associated mortality in most developed countries. 3,5-Diaryl substituted pyrazole derivatives (20-28) were prepared starting from related chalcones and biologically evaluated for in vitro growth inhibition activity against PC3 and DU145 human prostate cancer cell lines. Compounds 23, 26, and 28 were found to be more potent as compared to the other halogen-substituted derivatives. Especially, the 2-bromo-substituted pyrazole derivative (26) was found to be more potent against PC3 and DU145 cells. Epidermal growth factor receptor (EGFR) and vascular endothelial growth factor receptor 2 (VEGFR2) are known to be expressed in DU145 and PC3 cancer cells. The binding mode of the most selective compound 26 toward EGFR and VEGFR2 was investigated by employing docking simulations based on GLIDE standard precision (-5.912 and -6.949 kcal/mol, respectively).

Design, Synthesis, and Anticancer Activity Studies of Novel Quinoline-Chalcone Derivatives

The chalcone and quinoline scaffolds are frequently utilized to design novel anticancer agents. As the continuation of our work on effective anticancer agents, we assumed that linking chalcone fragment to the quinoline scaffold through the principle of molecular hybridization strategy could produce novel compounds with potential anticancer activity. Therefore, quinoline-chalcone derivatives were designed and synthesized, and we explored their antiproliferative activity against MGC-803, HCT-116, and MCF-7 cells. Among these compounds, compound 12e exhibited a most excellent inhibitory potency against MGC-803, HCT-116, and MCF-7 cells with IC50 values of 1.38, 5.34, and 5.21 µM, respectively. The structure-activity relationship of quinoline-chalcone derivatives was preliminarily explored in this report. Further mechanism studies suggested that compound 12e inhibited MGC-803 cells in a dose-dependent manner and the cell colony formation activity of MGC-803 cells, arrested MGC-803 cells at the G2/M phase and significantly upregulated the levels of apoptosis-related proteins (Caspase3/9 and cleaved-PARP) in MGC-803 cells. In addition, compound 12e could significantly induce ROS generation, and was dependent on ROS production to exert inhibitory effects on gastric cancer cells. Taken together, all the results suggested that directly linking chalcone fragment to the quinoline scaffold could produce novel anticancer molecules, and compound 12e might be a valuable lead compound for the development of anticancer agents.

Chalcone Derivatives: Role in Anticancer Therapy

Chalcones (1,3-diaryl-2-propen-1-ones) are precursors for flavonoids and isoflavonoids, which are common simple chemical scaffolds found in many naturally occurring compounds. Many chalcone derivatives were also prepared due to their convenient synthesis. Chalcones as weandhetic analogues have attracted much interest due to their broad biological activities with clinical potentials against various diseases, particularly for antitumor activity. The chalcone family has demonstrated potential in vitro and in vivo activity against cancers via multiple mechanisms, including cell cycle disruption, autophagy regulation, apoptosis induction, and immunomodulatory and inflammatory mediators. It represents a promising strategy to develop chalcones as novel anticancer agents. In addition, the combination of chalcones and other therapies is expected to be an effective way to improve anticancer therapeutic efficacy. However, despite the encouraging results for their response to cancers observed in clinical studies, a full description of toxicity is required for their clinical use as safe drugs for the treatment of cancer. In this review, we will summarize the recent advances of the chalcone family as potential anticancer agents and the mechanisms of action. Besides, future applications and scope of the chalcone family toward the treatment and prevention of cancer are brought out.

Piperazine skeleton in the structural modification of natural products: a review

Piperazine moiety is a cyclic molecule containing two nitrogen atoms in positions 1 and 4, as well as four carbon atoms. Piperazine is one of the most sought heterocyclics for the development of new drug candidates with a wide range of applications. Over 100 molecules with a broad range of bioactivities, including antitumor, antibacterial, anti-inflammatory, antioxidant, and other activities, were reviewed. This article reviewed investigations regarding piperazine groups for the modification of natural product derivatives in the last decade, highlighting parameters that affect their biological activity.

Novel ginsenoside derivatives have shown their effects on PC-3 cells by inducing G1-phase arrest and reactive oxygen species-mediate cell apoptosis

In this study, piperazine groups were introduced into ginsenoside to enhance its ability to induce Reactive Oxygen Species (ROS) production and apoptosis in cancer cells. In total, 27 ginsenoside piperazine derivatives were synthesized and tested for their anti-proliferative activity in cancer cell lines by MTT assay. The results showed that compounds 4a, 4g, 4f, 4i, 5g, 5i, 6a, 6g, 6f and 6i had significant inhibitory effects on cancer cell growth. Compound 6g showed the strongest anti-proliferative effect on PC-3 cells with an IC₅₀ of 1.98 ± 0.34 μM. Compound 6g could also induce G1-phase arrest and apoptosis in PC-3 cells, with apoptosis rates of 8.1%, 41% and 56.1% observed at 5, 10 and 20 μM, respectively. Compound 6g also significantly enhanced the intracellular fluorescence of ROS sensitive substrates, with a fluorescence intensity ratio of 23.1% observed in treated cells, indicative of ROS production. Following N-acetylcysteine treatment, apoptotic rates of the cancer cell lines decreased from 38.9% to 7.3%, and the expression of Cl-PARP, Cl-Caspase-3 and Cl-Caspase-9 also decreased, confirming that compound 6g induced apoptosis through ROS induction. Compound 6g also stimulated the translocation of Bax from the cytoplasm to the mitochondria, which enhanced Cytochrome C (Cyt C) release, and increased the expression of the apoptotic markers Cl-PARP, Cl-Caspase-3, and Cl-Caspase-9 in PC-3 cells. Taken together, these data reveal the anti-cancer effects of compound 6g that enhance ROS production, and then induce apoptosis through mitochondrial pathway.

Synthesis and Biological Evaluation of Amino Chalcone Derivatives as Antiproliferative Agents

Chalcone is a common scaffold found in many biologically active compounds. The chalcone scaffold was also frequently utilized to design novel anticancer agents with potent biological efficacy. Aiming to continue the research of effective chalcone derivatives to treat cancers with potent anticancer activity, fourteen amino chalcone derivatives were designed and synthesized. The antiproliferative activity of amino chalcone derivatives was studied in vitro and 5-Fu as a control group. Some of the compounds showed moderate to good activity against three human cancer cells (MGC-803, HCT-116 and MCF-7 cells) and compound 13e displayed the best antiproliferative activity against MGC-803 cells, HCT-116 cells and MCF-7 cells with IC₅₀ values of 1.52 μM (MGC-803), 1.83 μM (HCT-116) and 2.54 μM (MCF-7), respectively which was more potent than the positive control (5-Fu). Further mechanism studies were explored. The results of cell colony formatting assay suggested compound 10e inhibited the colony formation of MGC-803 cells. DAPI fluorescent staining and flow cytometry assay showed compound 13e induced MGC-803 cells apoptosis. Western blotting experiment indicated compound 13e induced cell apoptosis via the extrinsic/intrinsic apoptosis pathway in MGC-803 cells. Therefore, compound 13e might be a valuable lead compound as antiproliferative agents and amino chalcone derivatives worth further effort to improve amino chalcone derivatives' potency.

An insight into medicinal attributes of dithiocarbamates: Bird's eye view

Dithiocarbamates are considered as an important motif owing to its extensive biological applications in medicinal chemistry. The synthesis of this framework can easily be achieved via a one-pot reaction of primary/secondary amines, CS₂, and alkyl halides under catalyst-free conditions or sometimes in the presence of a base. By virtue of its colossal pharmacological scope, it has been an evolving subject of interest for many researchers around the world. The present review aims to highlight various synthetic approaches for dithiocarbamates with the major emphasis on medicinal attributes of these architectures as leads in the drug discovery of small molecules such as HDAC inhibitor, lysine-specific demethylase 1 (LSD1) down-regulator, kinase inhibitor (focal adhesion kinase, pyruvate kinase, Bruton's tyrosine kinase), carbonic anhydrase inhibitor, DNA intercalators, and apoptosis-inducing agents. Moreover, recent medicinal advancements in the synthesis of dithiocarbamate derivatives as anticancer, antifungal, antibacterial, anti-Alzheimer, antitubercular, anti-glaucoma, anti-cholinergic, antihyperglycemic, anti-inflammatory activities have been elaborated with notable examples.

Chalcone hybrids as potential anticancer agents: Current development, mechanism of action, and structure-activity relationship

The continuous emergency of drug-resistant cancers and the low specificity of anticancer agents have been the major challenges in the control and treatment of cancer, making an urgent need to develop novel anticancer agents with high efficacy. Chalcones, precursors of flavonoids and isoflavonoids, exhibit structural heterogeneity and can act on various drug targets. Chalcones which demonstrated potential in vitro and in vivo activity against both drug-susceptible and drug-resistant cancers, are useful templates for the development of novel anticancer agents. Hybridization of chalcone moiety with other anticancer pharmacophores could provide the hybrids which have the potential to overcome drug resistance and improve the specificity, so it represents a promising strategy to develop novel anticancer agents. This review emphasizes the development, the mechanisms of action as well as structure-activity relationships of chalcone hybrids with potential therapeutic application for many cancers in recent 10 years.

Antiproliferative Effect of Acridine Chalcone Is Mediated by Induction of Oxidative Stress

Chalcones are naturally occurring phytochemicals with diverse biological activities including antioxidant, antiproliferative, and anticancer effects. Some studies indicate that the antiproliferative effect of chalcones may be associated with their pro-oxidant effect. In the present study, we evaluated contribution of oxidative stress in the antiproliferative effect of acridine chalcone 1C ((2 E)-3-(acridin-9-yl)-1-(2,6-dimethoxyphenyl)prop-2-en-1-one) in human colorectal HCT116 cells. We demonstrated that chalcone 1C induced oxidative stress via increased reactive oxygen/nitrogen species (ROS/RNS) and superoxide production with a simultaneous weak adaptive activation of the cellular antioxidant defence mechanism. Furthermore, we also showed chalcone-induced mitochondrial dysfunction, DNA damage, and apoptosis induction. Moreover, activation of mitogen activated phosphokinase (MAPK) signalling pathway in 1C-treated cancer cells was also observed. On the other hand, co-treatment of cells with strong antioxidant, N-acetyl cysteine (NAC), significantly attenuated all of the above-mentioned effects of chalcone 1C, that is, decreased oxidant production, prevent mitochondrial dysfunction, DNA damage, and induction of apoptosis, as well as partially preventing the activation of MAPK signalling. Taken together, we documented the role of ROS in the antiproliferative/pro-apoptotic effects of acridine chalcone 1C. Moreover, these data suggest that this chalcone may be useful as a promising anti-cancer agent for treating colon cancer.

Isocordoin analogues promote apoptosis in human melanoma cells via Hsp70

Isocordin 1 and a series of 4-oxyalkyl-isocordoin analogues 2-8 were evaluated for their cytotoxicity effect against human melanoma cells (A2058). Analogues 4, 5, and 6 showed a higher inhibitory activity with IC₅₀ values of 12.91 ± 0.031, 24.88 ± 0.013, and 11.62 ± 0.017, respectively. These analogues, 4, 5, and 6, also induced an apoptotic response at 12.5- and 25-μM concentrations. They inhibited the expression of antiapoptotic proteins Bcl-2 and Hsp70, a critical factor that promotes tumour cell survival. In contrast, Bax and caspase-9 expression, and caspase-3 enzyme resulted activated. These results were correlated to a DNA fragmentation typical of apoptosis and an increase of intracellular reactive oxygen species (ROS) levels. Alternatively, at higher concentration (50 μM), when the capacity of the cells to sustain Hsp70 synthesis is reduced, our results seem to indicate that necrosis was induced by a further increase in ROS production. Therefore, the central finding in the present study is that these molecules downregulates Hsp70 expression. Altogether, these results suggest that 4-oxyalkyl-isocordoin analogues 4, 5, and 6 deserve to be deeply investigated for a possible application as Hsp70 inhibitor in the management of melanoma.