Potent Antiproliferative Activity Research Articles

Synthesis, Biological Activities, and Molecular Docking Studies of 15-Site Matrine Based Isatohydrazone Derivatives as Potential Anticancer Agents.

To acquire matrine derivatives with enhanced anticancer activity, we designed and synthesized twenty-one 15-site matrine based isatohydrazone derivatives were designed and synthesized. The anti-proliferative activity of all the compounds against human cervical cancer cells (HeLa), human colon cancer cells (HCT116), and non-small cell lung cancer cells (A549) was examined by the MTT method. The majority of the compounds exhibited superior anticancer activity compared to matrine. Among them, compound 5a displayed the most potent anti-proliferative activity, with IC50 values of 9.02±0.33 μM (HeLa), 10.49±1.09 μM (HCT116), and 15.23±0.12 μM (A549), respectively. Compound 5a can also induce cell cycle arrest in the G0/G1 phase and trigger apoptosis, as well as inhibit cell clonal formation and migration. Molecular docking experiments have demonstrated that compound 5a can form hydrogen bonds and hydrophobic interactions with EGFR-related protein 7AEI.

Discovery of the First-in-Class Dual-Target ROCK/HDAC Inhibitor with Potent Antitumor Efficacy in Vivo That Trigger Antitumor Immunity.

Triple-negative breast cancer (TNBC) represents a highly aggressive and heterogeneous malignancy. Currently, multitarget drug approaches present a promising therapeutic approach for TNBC. Utilizing a combinatorial chemistry strategy to construct a virtual screening database, dual ROCK/HDAC-targeting benzothiophene compounds were identified. Notably, compound 10h effectively inhibits ROCK1/2 and HDAC1/2/3/6/8 while demonstrating potent antiproliferative activity against breast cancer cells. In an orthotopic mouse model of breast cancer, 10h significantly suppressed tumor growth without apparent toxicity. Importantly, 10h induced immunogenic cell death (ICD), promoted dendritic cells (DCs) maturation, and activated T cells, thereby initiating antitumor immunity. In conclusion, compound 10h is a novel dual-target ROCK/HDAC inhibitor that represents a promising treatment strategy for TNBC.

An enzyme-responsive double-locked amonafide prodrug for the treatment of glioblastoma with minimal side effects.

Amonafide (ANF), a topoisomerase II inhibitor and DNA intercalator, has exhibited promise in phase II trials but faces significant limitations due to adverse side effects. Here, we have developed a novel enzyme-triggered fluorogenic prodrug, AcKLP, that incorporates dual-locked enzyme activation, ensuring that the prodrug remains inactive until it confronts the unique enzymatic environment of glioblastoma cells. This approach minimizes premature activation and reduces toxicity to normal cells, with an IC50 > 100 μM for human umbilical vein endothelial cells (HUVEC) and ∼2.3 μM for human glioblastoma cells (U87). Upon activation of AcKLP by two distinct enzymes prevalent in glioblastoma cells, amonafide is released and emits a fluorescence signal response, facilitating treatment and the monitoring of real-time drug distribution. Mechanistic studies indicate that AcKLP mainly induces autophagic cell death in U87 cells. Moreover, three-dimensional multicellular U87 tumor spheroid assays and in vivo experiments confirm the potent antiproliferative activity of AcKLP against glioblastoma cells. This work demonstrates a novel de-caging strategy to improve the selectivity and efficacy of amonafide for cancer therapy.

Multicomponent Syntheses Enable the Discovery of Novel Quisinostat-Derived Chemotypes as Histone Deacetylase Inhibitors

In this study, we synthesized and evaluated novel histone deacetylase (HDAC) inhibitors derived from the clinical candidate quisinostat. A library of 16 compounds categorized in three novel chemotypes was rapidly generated using multicomponent reactions (MCRs), enabling efficient structure-activity relationship studies. First, the compounds were evaluated for their activity against the Plasmodium falciparum strains 3D7 and Dd2, the main malaria-causing parasite, identifying compound 18b of the type C series as the most potent. It demonstrated low nanomolar IC50 values (IC50 (3D7) = 0.023 μM; IC50 (Dd2) = 0.047 μM) and high parasite selectivity (SIMRC-5/Pf3D7 > 2174). HDAC inhibition assays confirmed substantial inhibition of the P. falciparum enzyme PfHDAC1 (IC50 = 0.037 μM) as well as of human HDAC1 (IC50 = 0.021 μM) and HDAC6 (IC50 = 0.25 μM). Docking studies suggested distinct binding modes of 18b in P. falciparum and human HDAC1. Additionally, the in vitro anticancer activity was evaluated in Cal27 (head-neck carcinoma), HepG2 (hepatocellular carcinoma), A2780 (ovarian carcinoma), and U87 (glioblastoma) cell lines. Compounds 9b, 9d, and 13f showed potent antiproliferative activity and caspase 3/7 activation, in contrast to 18b. Furthermore, these compounds caused hyperacetylation of histone H3 and α-tubulin, indicating robust cellular target engagement. Overall, in this work we have identified the HDAC inhibitor 18b with selective antiplasmodial and 9b, 9d, and 13f with selective anticancer activities, providing valuable hits for further drug development efforts aimed at creating derivatives with reduced cytotoxicity against non-cancer cells compared to quisinostat.

A potent dual inhibitor targeting COX-2 and HDAC of acute myeloid leukemia cells.

Acute myeloid leukemia (AML) is an aggressive cancer with complex issues of drug resistance and a poor prognosis; thus, effective therapeutics is urgently needed for AML. In this study, we designed and synthesized dual cyclooxygenase-2 (COX-2) and histone deacetylase (HDAC) inhibitors, IMC-HA and IMC-OPD, and applied them for the treatment of AML. IMC-HA comprised a COX-2 inhibitor skeleton of indomethacin (IMC) and an HDAC inhibitor moiety of the hydroxamic group and was found to exhibit potent antiproliferative activity against AML cells (THP-1 and U937) and low cytotoxicity toward normal cells. Molecular docking simulations suggested that IMC-HA had a high binding affinity for HDAC and COX-2, with binding energies of -6.8 and -9.0kcal/mol, respectively. Mechanistic studies revealed that IMC-HA induced apoptosis and G0/G1 phase arrest in AML cells, which were characterized by alterations in the expression of apoptotic and cell cycle-related proteins. Further study demonstrated that IMC-HA also inhibited the MEK/ERK signaling pathway in AML cells. Overall, we believe that IMC-HA could serve as a potent COX-2/HDAC dual inhibitor and improve the treatment of AML.

Indolo[3,2-c]isoquinoline Hydroxamic Acid Derivatives as Novel Orally Topoisomerase-Histone Deacetylase Dual Inhibitors for NSCLC Therapy.

Based on the synergistic effects of topoisomerase (Top) inhibitors and histone deacetylase (HDAC) inhibitors in cancer therapy, a series of novel Top/HDAC dual inhibitors were designed and synthesized herein. The optimal compound 31 was identified to simultaneously inhibit both Tops and HDACs with potent antiproliferative activity against nonsmall cell lung cancer (NSCLC). Mechanistic studies indicated that compound 31 with increasing reactive oxygen species levels damages DNA, inhibiting cancer cell colony formation and migration and inducing both cancer cell apoptosis and cycle arrest. Noteworthily, compound 31 was orally active in the NSCLC xenograft model, and its antitumor efficacy (TGI = 77.5%, 100 mg/kg) was superior to that of HDAC inhibitor SAHA and SAHA in combination with the Top inhibitor irinotecan. Consequently, this work highlights the therapeutic potential of compound 31 as the Top/HDAC dual inhibitor in NSCLC therapy and provides valuable lead compounds for the further development of antitumor agents in solid tumor therapy.

Discovery of dual-targeted molecules based on Olaparib and Rigosertib for triple-negative breast cancer with wild-type BRCA

PARP inhibitors (PARPis) demonstrate significant potential efficacy in the clinical treatment of BRCA-mutated triple-negative breast cancer (TNBC). However, a majority of patients with TNBC do not possess BRCA mutations, and therefore cannot benefit from PARPis. Previous studies on multi-targeted molecules derived from PARPis or disruptors of RAF-RAF pathway have offered an alternative approach to develop novel anti-TNBC agents. Hence, to broaden the application of PARP inhibitors for TNBC patients with wild-type BRCA, a series of dual-targeted molecules were constructed via integrating the key pharmacophores of Olaparib (Ola) and Rigosertib into a single entity. Subsequent studies exhibited that the resulting compounds 13a–14c obtained potential anti-proliferative activity against BRCA-defected or wild-type TNBC cells. Among them, an optimal compound 13b showed good inhibitory activity toward PARP-1, displayed approximately 34-fold higher inhibitory activity than that of Ola in MDA-MB-231 cells, and exerted multi-functional mechanisms to induce apoptosis. Moreover, 13b displayed superior antitumor efficacy (TGI, 61.3 %) than the single administration of Ola (TGI, 38.5 %), 11b (TGI, 51.8 %) or even their combined administration (TGI, 56.7 %), but did not show significant systematic toxicity. These findings suggest that 13b may serve as a potential candidate for BRCA wild-type TNBC.

Total Synthesis of Rhizopodin Enabled by a Late-Stage Oxazole Ring Formation Strategy.

Actin stabilizers that are capable of interfering with actin cytoskeleton dynamics play an important role in chemical biology. Rhizopodin, a novel actin stabilizer, affects the actin cytoskeleton at nanomolar concentrations and exhibits potent antiproliferative activities against a range of tumor cell lines with IC50 values in the low nanomolar range. Herein, we report the total synthesis of rhizopodin based on a late-stage oxazole ring formation strategy, whose success demonstrates the feasibility of late-stage oxazole ring formation in the synthesis of complex oxazole containing natural products. Other features of the synthesis include a Nagao aldol reaction, a Suzuki coupling, a Yamaguchi esterification, a modified Robinson-Gabriel synthesis of the oxazoles, and a bidirectional Ba(OH)2-mediated Horner-Wadsworth-Emmons (HWE) reaction.

Appendage- and Scaffold-Diverse Electrophilic and Photoreactive Probes for Integrated Phenotypic Screening-Target Identification Campaigns via a Minimalist Bifunctional Isocyanide.

One of the grand challenges in chemical biology is identifying a small-molecule modulator for all proteins within a proteome. To expand the variety and number of ligandable proteins for drug discovery, the objective of this study was to synthesize and evaluate the protein target profiles of electrophilic and photoreactive fully functionalized small-molecule probes (FFSMPs) featuring increased scaffold-, appendage-, and protein-reactive functional group (PRFG) diversity. FFSMPs contain: (1) a protein-binding motif, (2) an electrophilic or photoreactive PRFG for target protein capture, and (3) a terminal alkyne for click chemistry-based proteomic applications. These compounds can be directly applied in phenotypic screening programs to identify ligand-protein pairs in cells unbiasedly. Herein, we highlight 17 examples from 34 structurally diverse FFSMPs featuring five electrophiles, three photoreactive groups, and 15 chemical scaffolds. Essential to the synthesis of the FFSMPs was a new minimalist bifunctional isocyanide in an "isocyanide-based multicomponent reaction-Boc deprotection-arming" synthetic sequence. To the best of our knowledge, this is the first report concerning the preparation of appendage- and scaffold-diverse FFSMPs for integrated phenotypic screening-target identification campaigns with the ability to examine either electrophilic or photoreactive PRFGs. In contrast, the status quo for such studies has been appendage-diverse FFSMPs comprised of a single chemical scaffold and a single PRFG, which limits efficient target protein capture and/or chemical space sampling significantly in the quest for discovering new drug targets and/or compounds with novel mechanisms of action. Phenotypic screening of the electrophilic members of our library identified several FFSMPs with potent antiproliferative activity against MCF10CA1a breast cancer cells. One of these FFSMPs (Compound 4a) covalently targeted and potently inhibited protein disulfide isomerase A1 (PDIA1). This study supports the continued use of minimalist bifunctional isocyanides as valuable building blocks for preparing structurally diverse FFSMPs for integrated phenotypic screening-target identification campaigns.

Discovery of novel quinazoline derivatives as tubulin polymerization inhibitors targeting the colchicine binding site with potential anti-colon cancer effects

Tubulin is a critical target for cancer therapy, with colchicine binding site inhibitors (CBSIs) being the most extensively researched. A series of quinazoline derivatives designed to target the colchicine binding site of tubulin were synthesized and evaluated for their biological activities. The antiproliferative effects of these compounds were tested against six human cancer cell lines, and compound Q19 demonstrated potent antiproliferative activity against the HT-29 cell line, with an IC50 value of 51 nM. Additionally, further investigation revealed that Q19 effectively inhibited microtubule polymerization by binding to the colchicine binding site on tubulin. Furthermore, compound Q19 arrested the HT-29 cell cycle at the G2/M phase, induced apoptosis in these cells, and disrupted angiogenesis. Finally, compound Q19 exhibited potent inhibitory effects on tumor growth in HT-29 xenografted mice while demonstrating minimal toxic side effects and acceptable pharmacokinetic properties. These findings suggested that Q19 hold promise as a potential candidate for colon cancer therapy targeting tubulin.

Cetirizine platinum(IV) complexes with antihistamine properties inhibit tumor metastasis by suppressing angiogenesis and boosting immunity

The histamine (HA) in tumors plays critical roles in promoting metastasis. Herein, a series of cetirizine (CTZ) platinum(IV) complexes with antihistamine properties were developed as antimetastatic agents. Dual CTZ platinum(IV) complex with cisplatin core was screened out as a candidate displaying potent antiproliferative activities. More importantly, it exerted promising antimetastatic properties both in vitro and in vivo. Investigation of the mechanism revealed that serious DNA damage was induced, which further led to the upregulation of histone H2AX (γ-H2AX) and P53. The mitochondria-mediated apoptosis was ignited through the B-cell lymphoma-2 (Bcl-2)/Bcl-2 associated X protein (Bax)/caspase3 pathway. Moreover, the HA-histamine receptor H1 (HRH1) axis was inhibited, then the key signaling phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) was suppressed. Subsequently, the angiogenesis in tumors was restrained by suppressing the inflammatory and hypoxic microenvironment. Then, the antitumor immunity was reinforced by increasing the CD3+ and CD8+ T cells and promoting the polarization of macrophages from M2- to M1-type, which was associated with the blockade of programmed cell death ligand-1 (PD-L1) expression in tumors.

SHR6390 Combined with Cabozantinib Inhibits Tumor Progression in the Hepatocellular Carcinoma Mouse Model.

A novel CDK4/6 inhibitor SHR6390 has shown significant anti-tumor effects. However, its role in hepatocellular carcinoma (HCC) remains unknown. To explore the inhibitory effect of combination treatment with SHR6390 and cabozantinib in HCC, and its antitumor mechanism, so as to provide a more effective therapeutic strategy for HCC patients. We investigated SHR6390, monotherapy or combined with cabozantinib, by CCK8, wound healing, transwell, western blotting, immunohistochemistry and mouse model of a subcutaneous tumor. Our results show that SHR6390 exhibited potent anti-proliferative activity against HCC in a dose-dependent manner. SHR6390 combined with cabozantinib exhibited more potent inhibition of cell viability, migration and invasion. In terms of potential mechanisms, we found that cabozantinib could lead to phosphorylation of Rb, which was reduced in SHR6390 and combined groups. SHR6390 monotherapy inhibited the growth of subcutaneous HCC tumors, besides, the combination treatment with SHR6390 and cabozantinib exerted synergistic anti-tumor activity in vivo Conclusion: SHR6390 is effective against HCC, monotherapy or combined with cabozantinib.

Discovery and Optimization of Ergosterol Peroxide Derivatives as Novel Glutaminase 1 Inhibitors for the Treatment of Triple-Negative Breast Cancer.

In this study, novel ergosterol peroxide (EP) derivatives were synthesized and evaluated to assess their antiproliferative activity against four human cancer cell lines (A549, HepG2, MCF-7, and MDA-MB-231). Compound 3g exhibited the most potent antiproliferative activity, with an IC50 value of 3.20 µM against MDA-MB-231. This value was 5.4-fold higher than that of the parental EP. Bioassay optimization further identified 3g as a novel glutaminase 1 (GLS1) inhibitor (IC50 = 3.77 µM). In MDA-MB-231 cells, 3g reduced the cellular glutamate levels by blocking the glutamine hydrolysis pathway, which triggered reactive oxygen species production and induced caspase-dependent apoptosis. Molecular docking indicated that 3g interacts with the reaction site of the variable binding pocket by forming multiple interactions with GLS1. In a mouse model of breast cancer, 3g showed remarkable therapeutic effects at a dose of 50 mg/kg, with no apparent toxicity. Based on these results, 3g could be further evaluated as a novel GLS1 inhibitor for triple-negative breast cancer (TNBC) therapy.

Screening of promising chemotherapeutic candidates from plants against human adult T-cell leukaemia/lymphoma (IX): active principles from Juniperus rigida

During the screening of novel chemotherapeutic candidates from plants against adult T-cell leukaemia/lymphoma (ATL), we found that extracts of plants in the Solanaceae, Annonaceae, Apocynaceae, and Rutaceae families showed anti-proliferative activity in the MT-1 and MT-2 cell lines. We have isolated active compounds from these plants in the present research because Cupressaceae plants showed potent anti-proliferative activity in the cell lines. We attempted to isolate the active compounds from the leaves of Juniperus rigida. Using activity-guided fractionation, we isolated 22 compounds, including seven terpenoids, three aromatic compounds, two iridoids, five lignans, and five biflavonoids. The anti-proliferative activities of five diterpenoids were moderate, and those of two biflavonoids were stronger. A lignan (compound 13) showed the strongest activity. These compounds are promising candidates for the treatment of ATL.

Design, Synthesis, and Biological Evaluation of 5-Amino-4-fluoro-1H-benzo[d]imidazole-6-carboxamide Derivatives as Novel and Potential MEK/RAF Complex Inhibitors Based on the "Clamp" Strategy.

Herein, we described the rational drug design and synthesis of a series of 5-amino-4-fluoro-1H-benzo[d]imidazole-6-carboxamide derivatives that inhibit MEK and RAF kinases. The detailed screening cascades revealed that 16b was a preferred compound, which might act like a "clamp" to stabilize the MEK/RAF complex, thereby effectively inhibiting MEK1, BRAF, and BRAFV600E with IC50 values of 28, 3, and 3 nM, respectively. 16b possessed an excellent selectivity over other 312 human-related kinases at 1 μM. In vitro, 16b showed potent antiproliferative activities against MIA PaCa-2 (G12C KRAS), HCT116 (G13D KRAS), and C26 (G12D KRAS) cells with IC50 values of 0.011, 0.079, and 0.096 μM, respectively. CoIP experiments demonstrated that 16b could induce MEK/RAF complex formation. Most importantly, in the C26 syngeneic colorectal and HCT116 mice xenograft tumor models, 16b demonstrated tumor growth inhibition of 70 and 93%, respectively, suggesting that 16b may be a promising MEK/RAF complex inhibitor and worthy of further development.

2-Arylbenzofurans from the stems and leaves of Artocarpus tonkinensis and their potential antiproliferative activities

Phytochemical study on the stems and leaves of Artocarpus tonkinensis led to the isolation of a new 2-arylbenzofuran, artocartone (1), as well as seven known 2-arylbenzofurans (2–8). The chemical structure of 1 was established by means of comprehensive spectroscopic analyses and the known compounds were determined by comparing their MS and NMR data with those reported data in literature. The antiproliferative activities of all isolates 1–8 against five human cancer cell lines: HL-60, SMMC-7721, A-375, MCF-7 and SW480 in vitro were evaluated. As a result, compounds 1– 8 displayed notable antiproliferative activities against various human cancer cell lines with IC50 values in the range of 0.28 ± 0.05–26.89 ± 0.18 μM.

Linkage-Editing of Melibiosamine: Synthesis and Biological Evaluation of CH2- and CHF-Linked Analogs.

Melibiosamine (Gal-α(1,6)-GlcNH2), consisting of galactose and glucosamine linked by an α(1,6)-glycosidic bond, is an artificial disaccharide derivative that selectively inhibits the proliferation of K562 tumor cells relative to HUC-F2 normal cells. In this study, we employed a linkage-editing strategy to synthesize CH2- and CHF-linked melibiosamine analogs through chemo- and stereoselective hydrogenation of fluorovinyl-C-glycoside. (R)-CHF-Melibiosamine exhibited more potent antiproliferative activity than O-linked melibiosamine, while (S)-CHF-melibiosamine was less potent.

Design and evaluation of sulfadiazine derivatives as potent dual inhibitors of EGFRWT and EGFRT790M: integrating biological, molecular docking, and ADMET analysis.

A series of derivatives (5-14) were synthesized through the diazotization of sulfadiazine with active methylene compounds. The chemical structures of these newly designed compounds were validated through spectral and elemental analysis techniques. The antiproliferative potential of derivatives 5-14 was assessed against three distinct cancer cell lines (A431, A549, and H1975) using the MTT assay. The results revealed that compounds 8, 12, and 14 exhibited the most potent antiproliferative activity, with IC50 values ranging from 2.31 to 7.56 μM. Notably, these values were significantly lower than those of known EGFR inhibitors, including erlotinib, gefitinib, and osimertinib, suggesting the potential of these derivatives as novel antiproliferative agents. Furthermore, compound 12 was identified as the most potent inhibitor of both EGFRWT and EGFRT790M protein kinases, with IC50 values of 14.5 and 35.4 nM, respectively. These results outperformed those of gefitinib and osimertinib, which exhibited IC50 values of 18.2 and 368.2 nM, and 57.8 and 8.5 nM, respectively. Molecular docking studies of compounds 8, 12, and 14 within the ATP-binding sites of both EGFRWT and EGFRT790M corroborated the in vitro results when compared to erlotinib, gefitinib, and osimertinib. The docking results indicated that compound 8 exhibited a favorable binding affinity for both EGFRWT and EGFRT790M, with binding scores of -6.40 kcal mol-1 and -7.53 kcal mol-1, respectively, which were comparable to those of gefitinib and osimertinib, with binding scores of -8.01 and -8.72 kcal mol-1, respectively. Furthermore, an assessment of the most promising EGFR inhibitors (8, 12, and 14) using the egg-boiled method for their in silico ADME properties revealed significant lipophilicity, blood-brain barrier (BBB) penetration, and gastrointestinal (GIT) absorption. Collectively, our designed analogs, particularly compounds 8, 12, and 14, exhibit promising dual antiproliferative and EGFRWT and EGFRT790M kinase inhibitory properties, positioning them as efficient candidates for further therapeutic development.

A Cyclometalated Iridium(III) Complex Exerts High Anticancer Efficacy via Fatty Acid Beta-Oxidation Inhibition and Sphingolipid Metabolism Reprogramming.

Given the extensive role of lipids in cancer development, there is substantial clinical interest in developing therapies that target lipid metabolism. In this study, we identified one cyclometalated iridium complex (Ir2) that exhibits potent antiproliferation activity in MIA PaCa-2 cells by regulating fatty acid metabolism and sphingolipid metabolism simultaneously. Ir2 also efficiently overcomes cisplatin resistance in vitro. Satisfyingly, the generated Ir2@F127 carriers, as a temperature-sensitive in situ gelling system of Ir2, showed effective cancer treatment with minimal side effects in an in vivo xenograft study. To the best of our knowledge, Ir2 is the first reported cyclometalated iridium complex that exerts anticancer activity in MIA PaCa-2 cells by intervening in lipid metabolism, which provides an alternative pathway for the anticancer mechanism of cyclometalated iridium complexes.

Discovery of novel 20S proteasome subunit β5 PROTAC degraders as potential therapeutics for pharyngeal carcinoma and Bortezomib-resistant multiple myeloma

Resistance to proteasome inhibitors like Bortezomib is a major challenge in the treatment of multiple myeloma (MM). Proteolysis targeting chimeras (PROTACs), an emerging therapeutic approach that induces selective degradation of target proteins, offer a promising solution to overcome drug resistance. In this study, we designed and synthesized novel small-molecule PROTACs that induce 20S proteasome subunit β5 degradation as a strategy to overcome Bortezomib resistance. These 20S proteasome subunit β5 PROTACs demonstrated considerable binding affinity to 20S proteasome subunit β5 and cereblon (CRBN), effectively induced 20S proteasome subunit β5 degradation, and exhibited potent antiproliferative activity against a panel of cancer cell lines. Notably, PROTACs 12f and 14 displayed robust antitumor effects against both the pharyngeal carcinoma cell line FaDu and the Bortezomib-resistant MM cell line KM3/BTZ in vitro and in vivo with excellent safety profiles. Taken together, our findings highlight the potential of PROTACs 12f and 14 as novel 20S proteasome subunit β5-degrading agents for the treatment of pharyngeal carcinoma and overcoming Bortezomib resistance in MM.