RESUMO
Liver cancer is a complex disease that involves various oncoproteins and the inactivation of tumor suppressor proteins (TSPs). Gankyrin is one such oncoprotein, first identified in human hepatocellular carcinoma, that is known to inactivate multiple TSPs, leading to proliferation and metastasis of tumor cells. Despite this, there has been limited development of small molecule gankyrin binders for the treatment of liver cancer. In this study, we are reporting the structure-based design of gankyrin-binding small molecules which inhibit the proliferation of HuH6 and HepG2 cells while also increasing the levels of certain TSPs, such as Rb and p53. Interestingly the first molecule to exhibit inhibition by 3D structure stabilization is seen. These results suggest a possible mechanism for small-molecule inhibition of gankyrin and demonstrate that gankyrin is a viable therapeutic target for the treatment of liver cancer.
Assuntos
Antineoplásicos , Proliferação de Células , Proteínas Proto-Oncogênicas , Triazóis , Humanos , Triazóis/química , Triazóis/farmacologia , Triazóis/síntese química , Proliferação de Células/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/síntese química , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Relação Estrutura-Atividade , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais , Ácidos Sulfônicos/química , Ácidos Sulfônicos/farmacologia , Ácidos Sulfônicos/antagonistas & inibidores , Linhagem Celular Tumoral , Ésteres/química , Ésteres/farmacologia , Ésteres/síntese química , Complexo de Endopeptidases do Proteassoma/metabolismo , Complexo de Endopeptidases do Proteassoma/química , Relação Dose-Resposta a Droga , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/metabolismo , BenzenossulfonatosRESUMO
Malignant pleural mesothelioma (MPM) is a rare and aggressive cancer affecting the pleural lining of the lungs. Celastrol (Cela), a pentacyclic triterpenoid, has demonstrated promising therapeutic potential as an antioxidant, anti-inflammatory, neuroprotective agent, and anti-cancer agent. In this study, we developed inhaled surface-modified Cela-loaded poly(lactic-co-glycolic) acid (PLGA) microparticles (Cela MPs) for the treatment of MPM using a double emulsion solvent evaporation method. The optimized Cela MPs exhibited high entrapment efficiency (72.8 ± 6.1%) and possessed a wrinkled surface with a mean geometric diameter of ~2 µm and an aerodynamic diameter of 4.5 ± 0.1 µm, suggesting them to be suitable for pulmonary delivery. A subsequent release study showed an initial burst release up to 59.9 ± 2.9%, followed by sustained release. The therapeutic efficacy of Cela MPs was evaluated against four mesothelioma cell lines, where Cela MP exhibited significant reduction in IC50 values, and blank MPs produced no toxicity to normal cells. Additionally, a 3D-spheroid study was performed where a single dose of Cela MP at 1.0 µM significantly inhibited spheroid growth. Cela MP was also able to retain the antioxidant activity of Cela only while mechanistic studies revealed triggered autophagy and an induction of apoptosis. Therefore, these studies highlight the anti-mesothelioma activity of Cela and demonstrate that Cela MPs are a promising inhalable medicine for MPM treatment.
Assuntos
Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurais , Humanos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Mesotelioma/tratamento farmacológico , Mesotelioma/patologia , Triterpenos Pentacíclicos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Pleurais/patologiaRESUMO
Tuberculosis (TB) is a contiguous airborne disease caused by Mycobacterium tuberculosis (M.tb), primarily affecting the human lungs. The progression of drug-susceptible TB to drug-resistant strains, MDR-TB and XDR-TB, has become a global challenge toward eradicating TB. Conventional TB treatment involves frequent dosing and prolonged treatment regimens predominantly by an oral or invasive route, leading to treatment-related systemic adverse effects and patient's noncompliance. Pulmonary delivery is an attractive option as we could reduce dose, limit systemic side-effects, and achieve rapid onset of action. Delamanid (DLD), an antituberculosis drug, has poor aqueous solubility, and in this study, we aim to improve its solubility using cyclodextrin complexation. We screened different cyclodextrins and found that HP-ß-CD resulted in a 54-fold increase in solubility compared to a 27-fold and 13-fold increase by SBE-ß-CD and HP-É£-CD, respectively. The stability constant (265 ± 15 M-1) and complexation efficiency (8.5 × 10-4) suggest the formation of a stable inclusion complex of DLD and HP-ß-CD in a 2:1 ratio. Solid-state characterization studies (DSC, PXRD, and NMR) further confirmed successful complexation of DLD in HP-ß-CD. The nebulized DLD-CD complex solution showed a mass median aerodynamic diameter of 4.42 ± 0.62 µm and fine particle fraction of 82.28 ± 2.79%, suggesting deposition in the respiratory airways. In bacterial studies, minimum inhibitory concentration of DLD-CD complex was significantly reduced (four-fold) compared to free DLD in M.tb (H37Ra strain). Furthermore, accelerated stability studies confirmed that the inclusion complex was stable for 4 weeks with 90%w/w drug content. In conclusion, we increased the aqueous solubility of DLD through cyclodextrin complexation and improved its efficacy in vitro.
Assuntos
Ciclodextrinas , Tuberculose Pulmonar , Tuberculose , Humanos , Ciclodextrinas/química , 2-Hidroxipropil-beta-Ciclodextrina , Solubilidade , Pulmão , Tuberculose Pulmonar/tratamento farmacológicoRESUMO
Polypharmacology is a concept where a molecule can interact with two or more targets simultaneously. It offers many advantages as compared to the conventional single-targeting molecules. A multi-targeting drug is much more efficacious due to its cumulative efficacy at all of its individual targets making it much more effective in complex and multifactorial diseases like cancer, where multiple proteins and pathways are involved in the onset and development of the disease. For a molecule to be polypharmacologic in nature, it needs to possess promiscuity which is the ability to interact with multiple targets; and at the same time avoid binding to antitargets which would otherwise result in off-target adverse effects. There are certain structural features and physicochemical properties which when present would help researchers to predict if the designed molecule would possess promiscuity or not. Promiscuity can also be identified via advanced state-of-the-art computational methods. In this review, we also elaborate on the methods by which one can intentionally incorporate promiscuity in their molecules and make them polypharmacologic. The polypharmacology paradigm of "one drug-multiple targets" has numerous applications especially in drug repurposing where an already established drug is redeveloped for a new indication. Though designing a polypharmacological drug is much more difficult than designing a single-targeting drug, with the current technologies and information regarding different diseases and chemical functional groups, it is plausible for researchers to intentionally design a polypharmacological drug and unlock its advantages.
Assuntos
Desenho de Fármacos , Polifarmacologia , Animais , HumanosRESUMO
PURPOSE: Glioblastoma multiforme (GBM) is a grade IV, highly proliferative, and malignant form of brain tumor with a 5-year survival rate at ~ 5%. Current treatment strategies for GBM include surgery, radiation, and chemotherapy. Major challenges in GBM management include difficulties in surgical resection due to brain's vital functions and GBM metastasis, development of resistance to temozolomide (TMZ), and protection of tumor by blood brain barrier (BBB). Therefore, we aimed to discover a novel therapeutic for GBM by targeting its metabolic reprogramming. METHOD: We screened metabolic inhibitors by their effects on GBM cell viability by MTT assay. We discovered an FDA-approved drug stiripentol (STP) in our screening of metabolic inhibitors in GBM cells. STP is used for Dravet syndrome (a rare epilepsy). We further tested efficacy of STP using proliferation assay, clonogenic assay, in vitro migration assay, cell cycle assay, apoptosis assay, and in U87 3D spheroids. We also tested the toxicity of STP, and combinations used in the study on normal human dermal fibroblasts. RESULTS: STP was effective in decreasing GBM cell viability, proliferation, clonogenic ability, and migration. Moreover, cell cycle changes were involved but robust apoptosis was absent in STP's anticancer effects. STP was effective in 3D spheroid models, and in TMZ-resistant cells. STP showed additive or synergistic effect with TMZ in different anticancer assays on GBM cells and was considerably less toxic in normal cells. CONCLUSION: Our results indicate that STP can be an effective GBM therapeutic that enhances the effects of TMZ on GBM cells. Importantly, STP reduced viability of TMZ-resistant cells. Our results warrant further studies in the mechanistic basis of STP's effects on GBM cells and the preclinical potential of STP in animal models.
Assuntos
Neoplasias Encefálicas , Glioblastoma , Animais , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/metabolismo , Anticonvulsivantes/farmacologia , Reposicionamento de Medicamentos , Linhagem Celular Tumoral , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Apoptose , Resistencia a Medicamentos Antineoplásicos , Antineoplásicos Alquilantes/uso terapêutico , Proliferação de Células , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
There is growing evidence that repurposed drugs demonstrate excellent efficacy against many cancers, while facilitating accelerated drug development process. In this study, bedaquiline (BDQ), an FDA approved anti-mycobacterial agent, was repurposed and an inhalable cyclodextrin complex formulation was developed to explore its anti-cancer activity in non-small cell lung cancer (NSCLC). A sulfobutyl ether derivative of ß-cyclodextrin (SBE-ß-CD) was selected based on phase solubility studies and molecular modeling to prepare an inclusion complex of BDQ and cyclodextrin. Aqueous solubility of BDQ was increased by 2.8 × 103-fold after complexation with SBE-ß-CD, as compared to its intrinsic solubility. Solid-state characterization studies confirmed the successful incorporation of BDQ in the SBE-ß-CD cavity. In vitro lung deposition study results demonstrated excellent inhalable properties (mass median aerodynamic diameter: 2.9 ± 0.6 µm (<5 µm) and fine particle fraction: 83.3 ± 3.8%) of BDQ-CD complex. Accelerated stability studies showed BDQ-CD complex to be stable up to 3 weeks. From cytotoxicity studies, a slight enhancement in the anti-cancer efficacy was observed with BDQ-cyclodextrin complex, compared to BDQ alone in H1299 cell line. The IC50 values for BDQ and BDQ-CD complex were found to be ~40 µM in case of H1299 cell line at 72 h, whereas BDQ/BDQ-CD were not found to be cytotoxic up to concentrations of 50 µM in A549 cell line. Taken together, BDQ-CD complex offers a promising inhalation strategy with efficient lung deposition and cytotoxicity for NSCLC treatment.
Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Diarilquinolinas/administração & dosagem , Portadores de Fármacos/química , Neoplasias Pulmonares/tratamento farmacológico , beta-Ciclodextrinas/química , Células A549 , Administração por Inalação , Antibióticos Antineoplásicos/farmacologia , Antituberculosos/administração & dosagem , Antituberculosos/farmacologia , Linhagem Celular Tumoral , Diarilquinolinas/farmacologia , Reposicionamento de Medicamentos , Humanos , Modelos MolecularesRESUMO
PURPOSE: This exploration is aimed at developing sorafenib (SF)-loaded cationically-modified polymeric nanoparticles (NPs) as inhalable carriers for improving the therapeutic efficacy of SF against non-small cell lung cancer (NSCLC). METHODS: The NPs were prepared using a solvent evaporation technique while incorporating cationic agents. The optimized NPs were characterized by various physicochemical parameters and evaluated for their aerosolization properties. Several in-vitro evaluation studies were performed to determine the efficacy of our delivery carriers against NSCLC cells. RESULTS: Optimized nanoparticles exhibited an entrapment efficiency of ~40%, <200 nm particle size and a narrow poly-dispersity index. Cationically-modified nanoparticles exhibited enhanced cellular internalization and cytotoxicity (~5-fold IC50 reduction vs SF) in various lung cancer cell types. The inhalable nanoparticles displayed efficient aerodynamic properties (MMAD ~ 4 µM and FPF >80%). In-vitro evaluation also resulted in a superior ability to inhibit cancer metastasis. 3D-tumor simulation studies further established the anti-cancer efficacy of NPs as compared to just SF. CONCLUSION: The localized delivery of SF-loaded nanoparticles resulted in improved anti-tumor activity as compared to SF alone. Therefore, this strategy displays great potential as a novel treatment approach against certain lung cancers.
Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/química , Sorafenibe/administração & dosagem , Administração por Inalação , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Cátions/química , Linhagem Celular Tumoral , Portadores de Fármacos/química , Humanos , Neoplasias Pulmonares/patologia , Nanopartículas/ultraestrutura , Tamanho da Partícula , Polímeros/química , Sorafenibe/farmacologiaRESUMO
Gankyrin is an oncogenic protein involved in various biological processes, such as cellular growth and proliferation. Its overexpression in certain cancers results in an increase of gankyrin-mediated protein-protein interactions (PPIs), leading to cancer proliferation. To date, only one small molecule (cjoc42) has been identified to bind gankyrin, which simultaneously inhibits its interaction with the 26S proteasome. Despite this advance, 2nd generation inhibitors are needed to improve gankyrin binding and cellular efficacy. To this end, an extensive SAR for the aryl sulfonate ester moiety of the cjoc42 scaffold was explored, and showed that substitutions at the 2-, 3-, and 4-positions manifested significant increases in gankyrin binding, resulting in the most potent binders of gankyrin to date. Subsequent cell-based assay evaluation of our derivatives demonstrated antiproliferative activity against pediatric liver cancer cell lines Hep3B and HepG2, which was not previously observed for cjoc42.
Assuntos
Antineoplásicos/química , Benzenossulfonatos/química , Ésteres/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Ácidos Sulfônicos/química , Triazóis/química , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Benzenossulfonatos/síntese química , Benzenossulfonatos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Simulação de Acoplamento Molecular , Ligação Proteica , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Triazóis/síntese química , Triazóis/farmacologiaRESUMO
Gankyrin is an oncoprotein overexpressed in numerous cancer types and appears to play a key role in regulating cell proliferation, cell growth, and cell migration. These roles are largely due to gankyrin's protein-protein interaction with the 26S proteasome. We previously published a study exploring the aryl sulfonate ester of cjoc42 in an effort to enhance gankyrin binding and inhibit cancer cell proliferation. In order to further improve the gankyrin binding ability of the cjoc42 scaffold, an extensive SAR for the aryl-triazole moiety of cjoc42 was developed. Our cjoc42 derivatives exhibited enhanced gankyrin binding, as well as enhanced antiproliferative activity against Hep3B, HepG2, A549, and MDA-MB-231 cancer cell lines.
Assuntos
Antineoplásicos/química , Benzenossulfonatos/química , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Triazóis/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Benzenossulfonatos/metabolismo , Benzenossulfonatos/farmacologia , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Simulação de Dinâmica Molecular , Complexo de Endopeptidases do Proteassoma/química , Ligação Proteica , Proteínas Proto-Oncogênicas/química , Relação Estrutura-Atividade , Triazóis/metabolismo , Triazóis/farmacologiaRESUMO
Pulmonary drug delivery is a noninvasive therapeutic approach that offers many advantages including localized drug delivery and higher patient compliance. As with all formulations, the low aqueous solubility of a drug often poses a challenge in the formulation development. Thus, strategies such as cyclodextrin (CD) complexation have been utilized to overcome this challenge. Resveratrol (RES), a natural stilbene, has shown abundant anti-cancer properties. Due to many drawbacks of conventional chemotherapeutics, RES has been proposed as an emerging alternative with promising pharmacological effects. However, RES has limited therapeutic applications due to low water solubility, chemical stability, and bioavailability. This study was aimed at developing an inhalable therapy that would increase the aqueous solubility and stability of RES by complexation with sulfobutylether-ß-cyclodextrin (SBECD). Phase solubility profiles indicated an optimal stoichiometric inclusion complex at 1:1 (SBECD:RES) ratio for formulation considerations. Physiochemical characterizations were performed to analyze CD-RES. Stability studies at pH 7.4 and in plasma indicated significant improvement in RES stability after complexation, with a much longer half-life. The mass median aerodynamic diameter (MMAD) of CD-RES was 2.6 ± 0.7 µm and fine particle fraction (FPF) of 83.4 ± 3.0% are suitable for pulmonary delivery and efficient deposition. Lung cancer was selected as the respiratory model disease, owing to its high relevance as the major cause of cancer deaths worldwide. Cell viability studies in 5 non-small-cell-lung-cancer (NSCLC) cell lines suggest CD-RES retained significant cytotoxic potential of RES. Taken together, CD-RES proves to be a promising inhalation treatment for NSCLC.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Ciclodextrinas/química , Neoplasias Pulmonares/tratamento farmacológico , Resveratrol/administração & dosagem , Administração por Inalação , Disponibilidade Biológica , Portadores de Fármacos/metabolismo , Estabilidade de Medicamentos , Humanos , Pulmão/metabolismo , SolubilidadeRESUMO
BACKGROUND: Mammary cancer is highly prevalent in dogs and cats and results in a poor prognosis due to critically lacking viable treatment options. Recent human and mouse studies have suggested that inhibiting peptidyl arginine deiminase enzymes (PAD) may be a novel breast cancer therapy. Based on the similarities between human breast cancer and mammary cancer in dogs and cats, we hypothesized that PAD inhibitors would also be an effective treatment for mammary cancer in these animals. METHODS: Canine and feline mammary cancer cell lines were treated with BB-Cl-Amidine (BB-CLA) and evaluated for viability and tumorigenicity. Endoplasmic reticulum stress was tested by western blot, immunofluorescence, and quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Canine and feline mammary cancer xenograft models were created using NOD scid gamma (NSG) mice, and were treated with BB-CLA for two weeks. RESULTS: We found that BB-CLA reduced viability and tumorigenicity of canine and feline mammary cancer cell lines in vitro. Additionally, we demonstrated that BB-CLA activates the endoplasmic reticulum stress pathway in these cells by downregulating 78 kDa Glucose-regulated Protein (GRP78), a potential target in breast cancer for molecular therapy, and upregulating the downstream target gene DNA Damage Inducible Transcript 3 (DDIT3). Finally, we established a mouse xenograft model of both canine and feline mammary cancer in which we preliminarily tested the effects of BB-CLA in vivo. CONCLUSION: We propose that our established mouse xenograft models will be useful for the study of mammary cancer in dogs and cats, and furthermore, that BB-CLA has potential as a novel therapeutic for mammary cancer in these species.
Assuntos
Amidinas/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neoplasias Mamárias Animais/metabolismo , Transdução de Sinais/efeitos dos fármacos , Amidinas/química , Animais , Gatos , Modelos Animais de Doenças , Cães , Chaperona BiP do Retículo Endoplasmático , Estresse do Retículo Endoplasmático/genética , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Feminino , Expressão Gênica , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/patologia , Desiminases de Arginina em Proteínas/genética , Desiminases de Arginina em Proteínas/metabolismo , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Dihydromotuporamineâ C and its derivatives were evaluated for their in vitro antimicrobial activities and antibiotic enhancement properties against Gram-negative bacteria and clinical isolates. The mechanism of action of one of these derivatives, MOTU-N44, was investigated against Enterobacter aerogenes by using fluorescent dyes to evaluate outer-membrane depolarization and permeabilization. Its efficiency correlated with inhibition of dye transport, thus suggesting that these molecules inhibit drug transporters by de-energization of the efflux pump rather than by direct interaction of the molecule with the pump. This suggests that depowering the efflux pump provides another strategy to address antibiotic resistance.
Assuntos
Alcaloides/química , Alcaloides/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Compostos Heterocíclicos com 1 Anel/farmacologia , Poliaminas/farmacologia , Antibacterianos/química , Anti-Infecciosos/química , Enterobacter aerogenes/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Compostos Heterocíclicos com 1 Anel/química , Proteínas de Membrana Transportadoras/metabolismo , Testes de Sensibilidade Microbiana , Poliaminas/químicaRESUMO
There are five peptidylarginine deiminase (PAD) isozymes designated as PADs 1, 2, 3, 4 and 6, and many are expressed in female reproductive tissues. These enzymes post-translationally convert positively charged arginine amino acids into neutral citrulline residues. Targets for PAD-catalyzed citrullination include arginine residues on histone tails, which results in chromatin decondensation and changes in gene expression. Some of the first studies examining PADs found that they are localized to rodent uterine epithelial cells. Despite these findings, the function of PAD-catalyzed citrullination in uterine epithelial cells is still unknown. To address this, we first examined PAD expression in uterine cross-sections from pregnant ewes on gestation day 25 (d25). Immunohistochemistry revealed that the levels of PADs 2 and 4 are robust in luminal and glandular epithelia compared with those of PADs 1 and 3. As PADs 2 and 4 have well-characterized roles in histone citrullination, we next hypothesized that PADs citrullinate histones in these uterine cells. Examination of caruncle lysates from pregnant ewes on gestation d25 and an ovine luminal epithelial (OLE) cell line shows that histone H3 arginine residues 2, 8, 17 and 26 are citrullinated, but histone H4 arginine 3 is not. Using a pan-PAD inhibitor, we next attenuated histone citrullination in OLE cells, which resulted in a significant decrease in the expression of insulin-like growth factor-binding protein 1 (IGFBP1) mRNA. As IGFBP1 is important for the migration and attachment of the trophectoderm to uterine endometrium, our results suggest that PAD-catalyzed citrullination may be an important post-translational mechanism for the establishment of pregnancy in ewes.
Assuntos
Citrulina/metabolismo , Células Epiteliais/metabolismo , Regulação da Expressão Gênica , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Processamento de Proteína Pós-Traducional , Desiminases de Arginina em Proteínas/metabolismo , Útero/metabolismo , Animais , Células Cultivadas , Citrulinação , Células Epiteliais/citologia , Feminino , Histonas/genética , Histonas/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ovinos , Útero/citologiaAssuntos
Antineoplásicos/farmacologia , Benzenossulfonatos/farmacologia , Ensaios de Triagem em Larga Escala , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Bibliotecas de Moléculas Pequenas/farmacologia , Triazóis/farmacologia , Antineoplásicos/química , Benzenossulfonatos/química , Sítios de Ligação/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Bibliotecas de Moléculas Pequenas/química , Relação Estrutura-Atividade , Triazóis/químicaRESUMO
Previously, we reported that the speA gene, encoding arginine decarboxylase, is required for swarming in the urinary tract pathogen Proteus mirabilis. In addition, this previous study suggested that putrescine may act as a cell-to-cell signaling molecule (Sturgill, G., and Rather, P. N. (2004) Mol. Microbiol. 51, 437-446). In this new study, PlaP, a putative putrescine importer, was characterized in P. mirabilis. In a wild-type background, a plaP null mutation resulted in a modest swarming defect and slightly decreased levels of intracellular putrescine. In a P. mirabilis speA mutant with greatly reduced levels of intracellular putrescine, plaP was required for the putrescine-dependent rescue of swarming motility. When a speA/plaP double mutant was grown in the presence of extracellular putrescine, the intracellular levels of putrescine were greatly reduced compared with the speA mutant alone, indicating that PlaP functioned as the primary putrescine importer. In urothelial cell invasion assays, a speA mutant exhibited a 50% reduction in invasion when compared with wild type, and this defect could be restored by putrescine in a PlaP-dependent manner. The putrescine analog Triamide-44 partially inhibited the uptake of putrescine by PlaP and decreased both putrescine stimulated swarming and urothelial cell invasion in a speA mutant.
Assuntos
Proteínas de Bactérias/metabolismo , Proteínas de Transporte/metabolismo , Infecções por Proteus/metabolismo , Proteus mirabilis/metabolismo , Putrescina/metabolismo , Urotélio/microbiologia , Proteínas de Bactérias/genética , Proteínas de Transporte/genética , Linhagem Celular , Humanos , Mutação , Infecções por Proteus/genética , Infecções por Proteus/microbiologia , Proteus mirabilis/genética , Proteus mirabilis/patogenicidade , Urotélio/patologiaRESUMO
Hsp90 isoform-selective inhibition is highly desired as it can potentially avoid the toxic side-effects of pan-inhibition. The current study developed selective inhibitors of one such isoform, Grp94, predicated on the chimeric and pan-Hsp90 inhibitor, radamide (RDA). Replacement of the quinone moiety of RDA with a phenyl ring (2) was found to be better suited for Grp94 inhibition as it can fully interact with a unique hydrophobic pocket present in Grp94. An extensive SAR for this scaffold showed that substitutions at the 2- and 4-positions (8 and 27, respectively) manifested excellent Grp94 affinity and selectivity. Introduction of heteroatoms into the ring also proved beneficial, with a 2-pyridine derivative (38) exhibiting the highest Grp94 affinity (K(d)=820 nM). Subsequent cell-based assays showed that these Grp94 inhibitors inhibit migration of the metastatic breast cancer cell line, MDA-MB-231, as well as exhibit an anti-proliferative affect against the multiple myeloma cell line, RPMI 8226.
Assuntos
Acetanilidas/química , Benzoatos/química , Proteínas de Choque Térmico HSP70/antagonistas & inibidores , Proteínas de Membrana/antagonistas & inibidores , Acetanilidas/metabolismo , Acetanilidas/farmacologia , Benzoatos/metabolismo , Benzoatos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Polarização de Fluorescência , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Isomerismo , Cinética , Proteínas de Membrana/metabolismo , Ligação Proteica , Relação Estrutura-AtividadeRESUMO
Background: Gankyrin is an ankyrin-repeat protein that promotes cell proliferation, tumor development and cancer progression when overexpressed. Aim: To design and synthesize a novel series of gankyrin-binding small molecules predicated on a 2,5-pyrimidine scaffold. Materials & methods: The synthesized compounds were evaluated for their antiproliferative activity, ability to bind gankyrin and effects on cell cycle progression and the proteasomal degradation pathway. Results: Compounds 188 and 193 demonstrated the most potent antiproliferative activity against MCF7 and A549 cells, respectively. Both compounds also demonstrated the ability to effectively bind gankyrin, disrupt proteasomal degradation and inhibit cell cycle progression. Conclusion: The 2,5-pyrimidine scaffold exhibits a novel and promising strategy for binding gankyrin and inhibiting cancer cell proliferation.
Assuntos
Neoplasias , Proteína Supressora de Tumor p53 , Humanos , Proteína Supressora de Tumor p53/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Neoplasias/metabolismo , Linhagem Celular TumoralRESUMO
A series of O-(4-nitrophenyl)hydroxylamines were synthesized from their respective oximes using a pulsed addition of excess NaBH(3)CN at pH 3 in 65-75% yield. Steric hindrance near the oxime functional group played a key role in both the ease by which the oxime could be reduced and the subsequent reactivity of the respective hydroxylamine. Reaction of the respective hydroxylamines with pyruvic acid derivatives generated the desired amides in good yields. A comparison of phenethylamine systems bearing different leaving groups revealed significant differences in the rates of these systems and suggested that the leaving group ability of the N-OR substituent plays an important role in determining their reactivity with pyruvic acid. Competition experiments (in 68% DMSO/phosphate buffered saline) using 1 equiv of N-phenethyl-O-(4-nitrophenyl)hydroxylamine and 2 equiv of pyruvic acid in the presence of other nucleophiles such as glycine, cysteine, phenol, hexanoic acid, and lysine demonstrated that significant chemoselectivity is present in this reaction. The results suggest that this chemoselective reaction can occur in the presence of excess α-amino acids, phenols, acids, thiols, and amines.
Assuntos
Amidas/química , Hidroxilaminas/síntese química , Nitrofenóis/síntese química , Ácido Pirúvico/química , Aminas/química , Aminoácidos/química , Hidroxilaminas/química , Estrutura Molecular , Nitrofenóis/química , Fenóis/químicaRESUMO
High-risk neuroblastoma (NB) represents a major clinical challenge in pediatric oncology due to relapse of metastatic, drug-resistant disease, and treatment-related toxicities. An analysis of 1235 primary NB patient dataset revealed significant increase in AKT1 and AKT2 gene expression with cancer stage progression. Additionally, Both AKT1 and AKT2 expression inversely correlate with poor overall survival of NB patients. AKT1 and AKT2 genes code for AKT that drive a major oncogenic cell signaling pathway known in many cancers, including NB. To inhibit AKT pathway, we repurposed an antiviral inhibitor BX-795 that inhibits PDK1, an upstream activator of AKT. BX-795 potently inhibits NB cell proliferation and colony growth in a dose-dependent manner. BX-795 significantly enhances apoptosis and blocks cell cycle progression at mitosis phase in NB. Additionally, BX-795 potently inhibits tumor formation and growth in a NB spheroid tumor model. We further tested dual therapeutic approaches by combining BX-795 with either doxorubicin or crizotinib and found synergistic and significant inhibition of NB growth, in contrast to either drug alone. Overall, our data demonstrate that BX-795 inhibits AKT pathway to inhibit NB growth, and combining BX-795 with current therapies is an effective and clinically tractable therapeutic approach for NB.
RESUMO
Background: Gankyrin, a member of the 26S proteasome, is an overexpressed oncoprotein in hepatoblastoma (HBL) and hepatocellular carcinoma (HCC). Cjoc42 was the first small molecule inhibitor of Gankyrin developed; however, the IC50 values of >50 µM made them unattractive for clinical use. Second-generation inhibitors demonstrate a stronger affinity toward Gankyrin and increased cytotoxicity. The aim of this study was to characterize the in vitro effects of three cjoc42 derivatives. Methods: Experiments were performed on the HepG2 (HBL) and Hep3B (pediatric HCC) cell lines. We evaluated the expression of TSPs, cell cycle markers, and stem cell markers by Western blotting and/or real-time quantitative reverse transcription PCR. We also performed apoptotic, synergy, and methylation assays. Results: The treatment with cjoc42 derivatives led to an increase in TSPs and a dose-dependent decrease in the stem cell phenotype in both cell lines. An increase in apoptosis was only seen with AFM-1 and -2 in Hep3B cells. Drug synergy was seen with doxorubicin, and antagonism was seen with cisplatin. In the presence of cjoc42 derivatives, the 20S subunit of the 26S proteasome was more available to transport doxorubicin to the nucleus, leading to synergy. Conclusion: Small-molecule inhibitors for Gankyrin are a promising therapeutic strategy, especially in combination with doxorubicin.