RESUMEN
Primary cilia are essential cellular antennae that transmit external signals into intracellular responses. These sensory organelles perform crucial tasks in triggering intracellular signaling pathways, including those initiated by G protein-coupled receptors (GPCRs). Given the involvement of GPCRs in serum-induced signaling, we investigated the contribution of ciliary proteins in mitogen perception and cell proliferation. We found that depletion of cilia via IFT88 silencing impaired cell growth and repressed YAP activation against serum and its mitogenic constituents, namely lysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P). To identify the key player of serum mitogen signaling, a mutant cell line library with 30 ablated individual ciliary proteins was established and screened based on YAP dephosphorylation and target gene induction. While 9 of them had altered signaling, ablation of IFT38 or IFT144 led to a particularly robust repression of YAP activation upon LPA and S1P. The deficiency of IFT38 and IFT144 attenuated cell proliferation, as corroborated in either 2-dimensional cultures or tumor spheroids. In subcutaneous skin melanoma patients, expression of IFT38 and IFT144 was associated with unfavorable outcomes in overall survival. In conclusion, our study demonstrates the involvement of ciliary proteins in mitogen signaling and identifies the regulatory roles of IFT38 and IFT144 in serum-mediated Hippo pathway signaling and cellular growth.
Asunto(s)
Mitógenos , Transducción de Señal , Humanos , Línea Celular , Proliferación Celular , Lisofosfolípidos/farmacología , Receptores Acoplados a Proteínas G/metabolismoRESUMEN
ß-Catenin is a multifunctional protein and participates in numerous processes required for embryonic development, cell proliferation, and homeostasis through various molecular interactions and signaling pathways. To date, however, there is no direct evidence that ß-catenin contributes to cytokinesis. Here, we identify a novel p-S60 epitope on ß-catenin generated by Plk1 kinase activity, which can be found at the actomyosin contractile ring of early telophase cells and at the midbody of late telophase cells. Depletion of ß-catenin leads to cytokinesis-defective phenotypes, which eventually result in apoptotic cell death. In addition, phosphorylation of ß-catenin Ser60 by Plk1 is essential for the recruitment of Ect2 to the midbody, activation of RhoA, and interaction between ß-catenin, Plk1, and Ect2. Time-lapse image analysis confirmed the importance of ß-catenin phospho-Ser60 in furrow ingression and the completion of cytokinesis. Taken together, we propose that phosphorylation of ß-catenin Ser60 by Plk1 in cooperation with Ect2 is essential for the completion of cytokinesis. These findings may provide fundamental knowledge for the research of cytokinesis failure-derived human diseases.
Asunto(s)
Actomiosina , Citocinesis , Actomiosina/metabolismo , Proteínas de Ciclo Celular/metabolismo , Células HeLa , Humanos , Fosforilación , Proteínas Serina-Treonina Quinasas , Proteínas Proto-Oncogénicas/metabolismo , Huso Acromático/metabolismo , beta Catenina/metabolismo , Quinasa Tipo Polo 1RESUMEN
Protein arginylation is a critical regulator of a variety of biological processes. The ability to uncover the global arginylation pattern and its associated signaling pathways would enable us to identify novel disease targets. Here, we report the development of a tool able to capture the N-terminal arginylome. This tool, termed R-catcher, is based on the ZZ domain of p62, which was previously shown to bind N-terminally arginylated proteins. Mutating the ZZ domain enhanced its binding specificity and affinity for Nt-Arg. R-catcher pulldown coupled to LC-MS/MS led to the identification of 59 known and putative arginylated proteins. Among these were a subgroup of novel ATE1-dependent arginylated ER proteins that are linked to diverse biological pathways, including cellular senescence and vesicle-mediated transport as well as diseases, such as Amyotrophic Lateral Sclerosis and Alzheimer's disease. This study presents the first molecular tool that allows the unbiased identification of arginylated proteins, thereby unlocking the arginylome and provide a new path to disease biomarker discovery.
Asunto(s)
Aminoaciltransferasas/metabolismo , Arginina/metabolismo , Retículo Endoplásmico/metabolismo , Vectores Genéticos/genética , Proteínas de la Membrana/metabolismo , Procesamiento Proteico-Postraduccional , Aminoaciltransferasas/química , Aminoaciltransferasas/genética , Arginina/química , Arginina/genética , Células HeLa , Humanos , Proteínas de la Membrana/genética , Especificidad por SustratoRESUMEN
Bisphenol A (BPA) is a typical environmental endocrine disruptor that exhibits estrogen-mimicking, hormone-like properties and can cause the collapse of bone homeostasis by an imbalance between osteoblasts and osteoclasts. Various BPA substitutes, structurally similar to BPA, have been used to manufacture 'BPA-free' products; however, the regulatory role of BPA alternatives in osteoclast differentiation still remains unelucidated. This study aimed to investigate the effects of these chemicals on osteoclast differentiation using the mouse osteoclast precursor cell line RAW 264.7. Results confirmed that both BPA and its alternatives, bisphenol F and tetramethyl bisphenol F (TMBPF), were nontoxic to RAW 264.7 cells. In particular, tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cell staining and activity calculation assays revealed that TMBPF enhanced osteoclast differentiation upon stimulation of the receptor activator of nuclear factor-kappa B ligand (RANKL). Additionally, TMBPF activated the mRNA expression of osteoclast-related target genes, such as the nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), tartrate-resistant acid phosphatase (TRAP), and cathepsin K (CtsK). Western blotting analysis indicated activation of the mitogen-activated protein kinase signaling pathway, including phosphorylation of c-Jun N-terminal kinase and p38. Together, the results suggest that TMBPF enhances osteoclast differentiation, and it is critical for bone homeostasis and skeletal health.
Asunto(s)
Compuestos de Bencidrilo/farmacología , Estrógenos no Esteroides/farmacología , Osteoblastos/efectos de los fármacos , Fenoles/farmacología , Animales , Resorción Ósea , Diferenciación Celular/efectos de los fármacos , Estrógenos/análogos & derivados , Estrógenos/farmacología , Macrófagos/efectos de los fármacos , Ratones , Proteínas Quinasas Activadas por Mitógenos/efectos de los fármacos , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Células RAW 264.7 , Transducción de Señal/efectos de los fármacosRESUMEN
In the past, several microtubule targeting agents (MTAs) have been developed into successful anticancer drugs. However, the usage of these drugs has been limited by the acquisition of drug resistance in many cancers. Therefore, there is a constant demand for the development of new therapeutic drugs. Here we report the discovery of 5-5 (3-cchlorophenyl)-N-(3-pyridinyl)-2-furamide (CPPF), a novel microtubule targeting anticancer agent. Using both 2D and 3D culture systems, we showed that CPPF was able to suppress the proliferation of diverse cancer cell lines. In addition, CPPF was able to inhibit the growth of multidrug-resistant cell lines that are resistant to other MTAs, such as paclitaxel and colchicine. Our results showed that CPPF inhibited growth by depolymerizing microtubules leading to mitotic arrest and apoptosis. We also confirmed CPPF anticancer effects in vivo using both a mouse xenograft and a two-step skin cancer mouse model. Using established zebrafish models, we showed that CPPF has low toxicity in vivo. Overall, our study proves that CPPF has the potential to become a successful anticancer chemotherapeutic drug.
Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Microtúbulos/metabolismo , Neoplasias/tratamiento farmacológico , Células A549 , Animales , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Colchicina/farmacología , Resistencia a Múltiples Medicamentos/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales/métodos , Células HeLa , Células Hep G2 , Humanos , Células Jurkat , Células K562 , Células MCF-7 , Masculino , Ratones , Mitosis/efectos de los fármacos , Neoplasias/metabolismo , Células PC-3 , Paclitaxel/farmacología , Células U937 , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Pez CebraRESUMEN
Elevated expression of human enhancer filamentation 1 (HEF1; also known as NEDD9 or Cas-L) is an essential stimulus for the metastatic process of various solid tumors. This process requires HEF1 localization to focal adhesions (FAs). Although the association of HEF1 with FAs is considered to play a role in cancer cell migration, the mechanism targeting HEF1 to FAs remains unclear. Moreover, up-regulation of Polo-like kinase 1 (Plk1) positively correlates with human cancer metastasis, yet how Plk1 deregulation promotes metastasis remains elusive. Here, we report that casein kinase 1δ (CK1δ) phosphorylates HEF1 at Ser-780 and Thr-804 and that these phosphorylation events promote a physical interaction between Plk1 and HEF1. We found that this interaction is critical for HEF1 translocation to FAs and for inducing migration of HeLa cells. Plk1-docking phosphoepitopes were mapped/confirmed in HEF1 by various methods, including X-ray crystallography, and mutated for functional analysis in HeLa cells. In summary, our results reveal the role of a phosphorylation-dependent HEF1-Plk1 complex in HEF1 translocation to FAs to induce cell migration. Our findings provide critical mechanistic insights into the HEF1-Plk1 complex-dependent localization of HEF1 to FAs underlying the metastatic process and may therefore contribute to the development of new cancer therapies.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Proteínas de Ciclo Celular/metabolismo , Adhesiones Focales/metabolismo , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas de Ciclo Celular/genética , Línea Celular , Proliferación Celular/genética , Proliferación Celular/fisiología , Adhesiones Focales/genética , Células HeLa , Humanos , Immunoblotting , Inmunoprecipitación , Fosfoproteínas/genética , Fosforilación/genética , Fosforilación/fisiología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Quinasa Tipo Polo 1RESUMEN
Polo-like kinase 1 (Plk1) regulates cell cycle and cell proliferation, and is currently considered a potential biomarker in clinical trials for many cancers. A characteristic feature of Plks is their C-terminal polo-box domain (PBD). Pro-Leu-His-Ser-pThr (PLHS[pT])-the phosphopeptide inhibitor of the PBD of Plk1-induces apoptosis in cancer cells. However, because of the low cell membrane-penetration ability of PLHS[pT], new approaches are required to overcome these drawbacks. We therefore developed a vitamin E (VE) conjugate that is biodegradable by intracellular redox enzymes as an anticancer drug-delivery system. To ensure high efficiency of membrane penetration, we synthesized VE-S-S-PLHS[pT]KY (1) by conjugating PLHS[pT] to VE via a disulfide bond. We found that 1 penetrated cancer cell membranes, blocked cancer cell proliferation, and induced apoptosis in cancer cells through cell cycle arrest in the G2/M phase. We synthesized a radiolabeled peptide (124I-1), and the radioligand was evaluated in in vivo tumor uptake using positron emission tomography. This study shows that combination conjugates are an excellent strategy for specifically targeting Plk PBD. These conjugates have a dual function, with possible uses in anticancer therapy and tumor diagnosis.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Proteínas de Ciclo Celular/metabolismo , Fosfopéptidos/química , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Vitamina E/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Células HeLa , Humanos , Mitosis/efectos de los fármacos , Quinasa Tipo Polo 1RESUMEN
Skin cancer is the most common type of cancer. The incidence rate of skin cancer has continuously increased over the past decades. In an effort to discover novel anticancer agents, we identified a novel tubulin inhibitor STK899704, which is structurally distinct from other microtubule-binding agents such as colchicine, vinca alkaloids and taxanes. STK899704 inhibited microtubule polymerization leading to mitotic arrest and suppressed the proliferation of various cancer cell lines as well as multidrug resistance cancer cell lines. In this study, our investigation is further extended into animal model to evaluate the effect of STK899704 on skin carcinogenesis in vivo. Surprisingly, almost 80% of the tumors treated with STK899704 were regressed with a one-fifth reduction in tumor volume. Furthermore, the efficacy of STK899704 was nearly 2 times higher than that of 5-fluorouracil, a widely used skin cancer therapeutic. Overall, our results suggest that STK899704 is a promising anticancer chemotherapeutic that may replace existing therapies, particularly for skin cancer.
Asunto(s)
Benzofuranos/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Moduladores de Tubulina/uso terapéutico , 9,10-Dimetil-1,2-benzantraceno , Animales , Antimetabolitos Antineoplásicos/uso terapéutico , Carcinogénesis , Colchicina/uso terapéutico , Modelos Animales de Enfermedad , Fluorouracilo/uso terapéutico , Masculino , Ratones , Neoplasias Cutáneas/inducido químicamente , Neoplasias Cutáneas/patología , Acetato de Tetradecanoilforbol , Tubulina (Proteína)/metabolismoRESUMEN
Atopic dermatitis (AD) is a chronic inflammatory skin disease whose prevalence is increasing worldwide. Filaggrin (FLG) is essential for the development of the skin barrier, and its genetic mutations are major predisposing factors for AD. In this study, we developed a convenient and practical method to detect FLG mutations in AD patients using peptide nucleic acid (PNA) probes labelled with fluorescent markers for rapid analysis. Fluorescence melting curve analysis (FMCA) precisely identified FLG mutations based on the distinct difference in the melting temperatures of the wild-type and mutant allele. Moreover, PNA probe-based FMCA easily and accurately verified patient samples with both heterozygote and homozygote FLG mutations, providing a high-throughput method to reliable screen AD patients. Our method provides a convenient, rapid and accurate diagnostic tool to identify potential AD patients allowing for early preventive treatment, leading to lower incidence rates of AD, and reducing total healthcare expenses.
Asunto(s)
Análisis Mutacional de ADN/métodos , Sondas de ADN , Dermatitis Atópica/diagnóstico , Dermatitis Atópica/genética , Proteínas de Filamentos Intermediarios/genética , Alelos , Estudios de Casos y Controles , Proteínas Filagrina , Fluorescencia , Heterocigoto , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Homocigoto , Humanos , Mutación , Ácidos Nucleicos de Péptidos/genética , Temperatura de TransiciónRESUMEN
Mammalian Plk1 is critically required for proper M phase progression. Plk1 is self-recruited to prekinetochores/kinetochores by phosphorylating and binding to the Thr-78 motif of a kinetochore scaffold protein, PBIP1 (also called CENP-U/50), which forms a stable complex with another kinetochore component, CENP-Q. However, the mechanism regulating Plk1 localization to this site remains largely unknown. Here, we demonstrate that the PBIP1·CENP-Q complex became hyperphosphorylated and rapidly delocalized from kinetochores as cells entered mitosis. Plk1 phosphorylated the CENP-Q subunit of the PBIP1·CENP-Q complex at multiple sites, and mutation of nine Plk1-dependent phosphorylation sites to Ala (9A) enhanced CENP-Q association with chromatin and prolonged CENP-Q localization to kinetochores. Conversely, mutation of the nine sites to phospho-mimicking Asp/Glu (9D/E) residues dissociated CENP-Q from chromatin and kept the CENP-Q(9D/E) mutant from localizing to interphase prekinetochores. Strikingly, both the 9A and 9D/E mutants induced a defect in proper chromosome segregation, suggesting that both timely localization of the PBIP1·CENP-Q complex to prekinetochores and delocalization from kinetochores are critical for normal M phase progression. Notably, although Plk1 did not alter the level of PBIP1 and CENP-Q ubiquitination, Plk1-dependent phosphorylation and delocalization of these proteins from kinetochores appeared to indirectly lead to their degradation in the cytosol. Thus, we propose that Plk1 regulates the timing of the delocalization and ultimate destruction of the PBIP1·CENP-Q complex and that these processes are important not only for promoting Plk1-dependent mitotic progression, but also for resetting the timing of Plk1 recruitment to prekinetochores in the next cell cycle.
Asunto(s)
Proteínas de Ciclo Celular/fisiología , Proteínas Cromosómicas no Histona/metabolismo , Segregación Cromosómica , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Proto-Oncogénicas/fisiología , Cromatina/metabolismo , Células HEK293 , Células HeLa , Histonas , Humanos , Cinetocoros/metabolismo , Complejos Multiproteicos/metabolismo , Fosforilación , Complejo de la Endopetidasa Proteasomal/metabolismo , Procesamiento Proteico-Postraduccional , Estabilidad Proteica , Transporte de Proteínas , Proteolisis , Ubiquitinación , Quinasa Tipo Polo 1RESUMEN
Two new phenylspirodrimane derivatives, stachybotrysin (1) and stachybotrylactone B (2), were isolated from the cultures of the marine-derived fungus Stachybotrys sp. KCB13F013. The structures were determined by analyzing the spectroscopic data (1D and 2D NMR and MS) and chemical transformation, including the modified Mosher's method and single-crystal X-ray structure analysis. Compound 1 exhibited an inhibitory effect on osteoclast differentiation in bone marrow macrophage cells via suppressing the RANKL-induced activation of p-ERK, p-JNK, p-p38, c-Fos, and NFATc1.
Asunto(s)
Osteoclastos/efectos de los fármacos , Stachybotrys/química , Animales , Células de la Médula Ósea/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Técnicas de Cocultivo , Regulación hacia Abajo/efectos de los fármacos , Macrófagos/efectos de los fármacos , Biología Marina , Ratones , Estructura Molecular , FN-kappa B/antagonistas & inhibidores , Osteoblastos/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/genética , Ligando RANK/farmacología , Transducción de Señal/efectos de los fármacosRESUMEN
The N-end rule pathway is a proteolytic system in which destabilizing N-terminal residues of short-lived proteins act as degradation determinants (N-degrons). Substrates carrying N-degrons are recognized by N-recognins that mediate ubiquitylation-dependent selective proteolysis through the proteasome. Our previous studies identified the mammalian N-recognin family consisting of UBR1/E3α, UBR2, UBR4/p600, and UBR5, which recognize destabilizing N-terminal residues through the UBR box. In the current study, we addressed the physiological function of a poorly characterized N-recognin, 570-kDa UBR4, in mammalian development. UBR4-deficient mice die during embryogenesis and exhibit pleiotropic abnormalities, including impaired vascular development in the yolk sac (YS). Vascular development in UBR4-deficient YS normally advances through vasculogenesis but is arrested during angiogenic remodeling of primary capillary plexus associated with accumulation of autophagic vacuoles. In the YS, UBR4 marks endoderm-derived, autophagy-enriched cells that coordinate differentiation of mesoderm-derived vascular cells and supply autophagy-generated amino acids during early embryogenesis. UBR4 of the YS endoderm is associated with a tissue-specific autophagic pathway that mediates bulk lysosomal proteolysis of endocytosed maternal proteins into amino acids. In cultured cells, UBR4 subpopulation is degraded by autophagy through its starvation-induced association with cellular cargoes destined to autophagic double membrane structures. UBR4 loss results in multiple misregulations in autophagic induction and flux, including synthesis and lipidation/activation of the ubiquitin-like protein LC3 and formation of autophagic double membrane structures. Our results suggest that UBR4 plays an important role in mammalian development, such as angiogenesis in the YS, in part through regulation of bulk degradation by lysosomal hydrolases.
Asunto(s)
Proteínas Asociadas a Microtúbulos/fisiología , Ubiquitina-Proteína Ligasas/fisiología , Saco Vitelino/irrigación sanguínea , Saco Vitelino/enzimología , Animales , Autofagia/genética , Autofagia/fisiología , Proteínas de Unión a Calmodulina/antagonistas & inhibidores , Proteínas de Unión a Calmodulina/genética , Proteínas de Unión a Calmodulina/fisiología , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Proteínas del Citoesqueleto/antagonistas & inhibidores , Proteínas del Citoesqueleto/genética , Proteínas del Citoesqueleto/fisiología , Desarrollo Embrionario/genética , Desarrollo Embrionario/fisiología , Endodermo/irrigación sanguínea , Endodermo/citología , Endodermo/enzimología , Femenino , Técnicas de Silenciamiento del Gen , Células HEK293 , Humanos , Mesodermo/irrigación sanguínea , Mesodermo/citología , Mesodermo/enzimología , Redes y Vías Metabólicas , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas Asociadas a Microtúbulos/deficiencia , Proteínas Asociadas a Microtúbulos/genética , Neovascularización Fisiológica/genética , Embarazo , Ubiquitina-Proteína Ligasas/deficiencia , Ubiquitina-Proteína Ligasas/genética , Saco Vitelino/citología , Saco Vitelino/embriologíaRESUMEN
Bone homeostasis is tightly regulated to balance bone formation and bone resorption. Many anabolic drugs are used as bone-targeted therapeutic agents for the promotion of osteoblast-mediated bone formation or inhibition of osteoclast-mediated bone resorption. Previous studies showed that ginsenoside Re has the effect of the suppression of osteoclast differentiation in mouse bone-marrow derived macrophages and zebrafish. Herein, we investigated whether ginsenoside Re affects osteoblast differentiation and mineralization in in vitro and in vivo models. Mouse osteoblast precursor MC3T3-E1 cells were used to investigate cell viability, alkaline phosphatase (ALP) activity, and mineralization. In addition, we examined osteoblastic signaling pathways. Ginsenoside Re affected ALP activity without cytotoxicity, and we also observed the stimulation of osteoblast differentiation through the activation of osteoblast markers including runt-related transcription factor 2, type 1 collagen, ALP, and osteocalcin in MC3T3-E1 cells. Moreover, Alizarin red S staining indicated that ginsenoside Re increased osteoblast mineralization in MC3T3-E1 cells and zebrafish scales compared to controls. These results suggest that ginsenoside Re promotes osteoblast differentiation as well as inhibits osteoclast differentiation, and it could be a potential therapeutic agent for bone diseases.
Asunto(s)
Resorción Ósea/tratamiento farmacológico , Diferenciación Celular/efectos de los fármacos , Ginsenósidos/farmacología , Osteoblastos/citología , Osteogénesis/efectos de los fármacos , Células 3T3 , Fosfatasa Alcalina/metabolismo , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colágeno Tipo I/metabolismo , Subunidad alfa 1 del Factor de Unión al Sitio Principal/metabolismo , Activación Enzimática/efectos de los fármacos , Ratones , Osteocalcina/metabolismo , Panax/química , Transducción de Señal/efectos de los fármacos , Pez CebraRESUMEN
Phosphatase and tensin homolog (PTEN) loss or mutation consistently activates the phosphatidylinositol 3-kinase (PI3-K)/Akt signaling pathway, which contributes to the progression and invasiveness of prostate cancer. Furthermore, the PTEN/PI3-K/Akt and Ras/MAPK pathways cooperate to promote the epithelial-mesenchymal transition (EMT) and metastasis initiated from prostate stem/progenitor cells. For these reasons, the PTEN/PI3-K/Akt pathway is considered as an attractive target for both chemoprevention and chemotherapy. Herein we report that eupafolin, a natural compound found in common sage, inhibited proliferation of prostate cancer cells. Protein content analysis indicated that phosphorylation of Akt and its downstream kinases was inhibited by eupafolin treatment. Pull-down assay and in vitro kinase assay results indicated that eupafolin could bind with PI3-K and attenuate its kinase activity. Eupafolin also exhibited tumor suppressive effects in vivo in an athymic nude mouse model. Overall, these results suggested that eupafolin exerts antitumor effects by targeting PI3-K.
Asunto(s)
Antineoplásicos Fitogénicos/uso terapéutico , Flavonas/uso terapéutico , Fosfatidilinositol 3-Quinasas/metabolismo , Próstata/efectos de los fármacos , Neoplasias de la Próstata/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Proliferación Celular/efectos de los fármacos , Humanos , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Modelos Moleculares , Próstata/metabolismo , Próstata/patología , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patologíaRESUMEN
Chrysin (5,7-dihydroxyflavone), a natural flavonoid widely distributed in plants, reportedly has chemopreventive properties against various cancers. However, the anticancer activity of chrysin observed in in vivo studies has been disappointing. Here, we report that a chrysin derivative, referred to as compound 69407, more strongly inhibited EGF-induced neoplastic transformation of JB6 P(+) cells compared with chrysin. It attenuated cell cycle progression of EGF-stimulated cells at the G1 phase and inhibited the G1/S transition. It caused loss of retinoblastoma phosphorylation at both Ser-795 and Ser-807/811, the preferred sites phosphorylated by Cdk4/6 and Cdk2, respectively. It also suppressed anchorage-dependent and -independent growth of A431 human epidermoid carcinoma cells. Compound 69407 reduced tumor growth in the A431 mouse xenograft model and retinoblastoma phosphorylation at Ser-795 and Ser-807/811. Immunoprecipitation kinase assay results showed that compound 69407 attenuated endogenous Cdk4 and Cdk2 kinase activities in EGF-stimulated JB6 P(+) cells. Pulldown and in vitro kinase assay results indicated that compound 69407 directly binds with Cdk2 and Cdk4 in an ATP-independent manner and inhibited their kinase activities. A binding model between compound 69407 and a crystal structure of Cdk2 predicted that compound 69407 was located inside the Cdk2 allosteric binding site. The binding was further verified by a point mutation binding assay. Overall results indicated that compound 69407 is an ATP-noncompetitive cyclin-dependent kinase inhibitor with anti-tumor effects, which acts by binding inside the Cdk2 allosteric pocket. This study provides new insights for creating a general pharmacophore model to design and develop novel ATP-noncompetitive agents with chemopreventive or chemotherapeutic potency.
Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Flavonoides/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Neoplasias Cutáneas/tratamiento farmacológico , Regulación Alostérica/efectos de los fármacos , Animales , Sitios de Unión , Carcinoma de Células Escamosas/enzimología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Cristalografía por Rayos X , Quinasas Ciclina-Dependientes/genética , Quinasas Ciclina-Dependientes/metabolismo , Factor de Crecimiento Epidérmico/genética , Factor de Crecimiento Epidérmico/metabolismo , Flavonoides/química , Fase G1/efectos de los fármacos , Fase G1/genética , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Modelos Moleculares , Trasplante de Neoplasias , Inhibidores de Proteínas Quinasas/química , Proteína de Retinoblastoma/genética , Proteína de Retinoblastoma/metabolismo , Fase S/efectos de los fármacos , Fase S/genética , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patologíaRESUMEN
Three new pyrrolobenzodiazepine derivatives, boseongazepines A-C (1-3), were isolated from a culture broth of Streptomyces sp. 11A057, together with the known compound usabamycin B (4). The structures of 1-4 were determined through the analysis of spectroscopic data including extensive 1D-, 2D-NMR, and MS techniques. Cell growth inhibition effects of these compounds were evaluated against Jurkat, K-562, HL-60, and HepG2 cell lines.
Asunto(s)
Antineoplásicos/farmacología , Benzodiazepinas/farmacología , Benzodiazepinonas/farmacología , Pirroles/farmacología , Streptomyces/química , Antineoplásicos/química , Antineoplásicos/aislamiento & purificación , Benzodiazepinas/química , Benzodiazepinas/aislamiento & purificación , Benzodiazepinonas/química , Benzodiazepinonas/aislamiento & purificación , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Células HL-60 , Células Hep G2 , Humanos , Células Jurkat , Células K562 , Conformación Molecular , Pirroles/química , Pirroles/aislamiento & purificación , Relación Estructura-ActividadRESUMEN
The secondary metabolites illudins C2 (1) and C3 (2), obtained from the culture broth of Coprinus atramentarius, have been shown to possess antimicrobial activity. In the present study, we discovered novel biological activities of 1 and 2 in lipolysis of differentiated 3T3-L1 adipocytes and adipogenesis of 3T3-L1 preadipocytes. Compounds 1 and 2 exhibit a dose-dependent increase in glycerol release and thereby reduce intracellular lipid accumulation. The stimulatory effects of 1 and 2 on lipolysis are prevented by cAMP-dependent protein kinase (PKA) and extracellular signal-regulated kinase (ERK) inhibitors. Compounds 1 and 2 down-regulated perilipin and also affected the mRNA and protein levels of adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL). However, 1 and 2 treatment leads to a significant increase in PKA-mediated phosphorylation of HSL at S563 and S660. In addition, 1 and 2 treatment in 3T3-L1 preadipocytes induces down-regulation of the critical transcription factors, CCAAT/enhancer binding protein α and ß (C/EBPα and C/EBPß), and peroxisome proliferator activated receptor γ (PPARγ), which are required for adipogenesis, and accordingly inhibits adipogenesis. These results suggest that 1 and 2 might be useful for treating obesity due to their modulatory effects on fat by affecting adipocyte differentiation and fat mobilization.
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Adipocitos/efectos de los fármacos , Adipogénesis/efectos de los fármacos , Proteína beta Potenciadora de Unión a CCAAT/efectos de los fármacos , Coprinus/química , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Lipasa/metabolismo , Lipólisis/efectos de los fármacos , PPAR gamma/metabolismo , Sesquiterpenos/aislamiento & purificación , Sesquiterpenos/farmacología , Células 3T3-L1 , Adipocitos/metabolismo , Adipogénesis/fisiología , Animales , Proteína alfa Potenciadora de Unión a CCAAT , Relación Dosis-Respuesta a Droga , Glicerol/análisis , Glicerol/metabolismo , Lipasa/análisis , Lipólisis/fisiología , Ratones , Estructura Molecular , Obesidad/tratamiento farmacológico , Sesquiterpenos Policíclicos , Sesquiterpenos/químicaRESUMEN
Bipolar spindle formation is pivotal for accurate segregation of mitotic chromosomes during cell division. A growing body of evidence suggests that, in addition to centrosome- and chromatin-based microtubule (MT) nucleation, MT-based MT nucleation plays an important role for proper bipolar spindle formation in various eukaryotic organisms. Although a recently discovered Augmin complex appears to play a central role in this event, how Augmin is regulated remains unknown. Here we provide evidence that a mammalian polo-like kinase 1 (Plk1) localizes to mitotic spindles and promotes MT-based MT nucleation by directly regulating Augmin. Mechanistically, we demonstrated that Cdc2-dependent phosphorylation on a γ-tubulin ring complex (γ-TuRC) recruitment protein, Nedd1/GCP-WD, at the previously uncharacterized S460 residue induces the Nedd1-Plk1 interaction. This step appeared to be critical to allow Plk1 to phosphorylate the Hice1 subunit of the Augmin complex to promote the Augmin-MT interaction and MT-based MT nucleation from within the spindle. Loss of either the Nedd1 S460 function or the Plk1-dependent Hice1 phosphorylation impaired both the Augmin-MT interaction and γ-tubulin recruitment to the spindles, thus resulting in improper bipolar spindle formation that ultimately leads to mitotic arrest and apoptotic cell death. Thus, via the formation of the Nedd1-Plk1 complex and subsequent Augmin phosphorylation, Plk1 regulates spindle MT-based MT nucleation to accomplish normal bipolar spindle formation and mitotic progression.
Asunto(s)
Proteínas de Ciclo Celular/metabolismo , Microtúbulos/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Proto-Oncogénicas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Sitios de Unión/genética , Proteína Quinasa CDC2 , Proteínas de Ciclo Celular/genética , Ciclina B/metabolismo , Quinasas Ciclina-Dependientes , Cartilla de ADN/genética , Células HeLa , Humanos , Proteínas Asociadas a Microtúbulos/química , Proteínas Asociadas a Microtúbulos/genética , Proteínas Asociadas a Microtúbulos/metabolismo , Centro Organizador de los Microtúbulos/metabolismo , Modelos Biológicos , Datos de Secuencia Molecular , Complejos Multiproteicos/metabolismo , Fosforilación , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas/genética , Interferencia de ARN , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Huso Acromático/metabolismo , Tubulina (Proteína)/metabolismo , Quinasa Tipo Polo 1RESUMEN
INTRODUCTION: Hypoxia-inducible factor 1 (HIF-1) is a transcriptional activator mediating adaptive responses to hypoxia. It is up-regulated in the tumor microenvironment and recognized as an effective anticancer drug target. Previously, we discovered that the natural compound moracin-O and its synthetic derivative MO-460 inhibited HIF-1α via hnRNPA2B1. OBJECTIVES: This study aimed to develop novel HIF-1 inhibitors for cancer chemotherapy by harnessing the potential of the natural products moracins-O and P. METHODS: In an ongoing search for novel HIF-1 inhibitors, a series of nature-inspired benzofurans with modifications on the chiral rings of moracins-O and P were synthesized. They showed improved chemical tractability and were evaluated for their inhibitory activity on HIF-1α accumulation under hypoxic conditions in HeLa CCL2 cells. The most potent derivative's chemical-based toxicities, binding affinities, and in vivo anti-tumorigenic effects were evaluated. Further, we examined whether our compound, MO-2097, exhibited anticancer effects in three-dimensional cultured organoids. RESULTS: Herein, we identified a novel synthetic chiral-free compound, MO-2097, with reduced structural complexity and increased efficiency. MO-2097 exhibited inhibitory effects on hypoxia-induced HIF-1α accumulation in HeLa CCL2 cells via inhibition of hnRNPA2B1 protein, whose binding affinities were confirmed by isothermal titration calorimetry analysis. In addition, MO-2097 demonstrated in vivo efficacy and biocompatibility in a BALB/c mice xenograft model. The immunohistochemistry staining of MO-2097-treated tissues showed decreased expression of HIF-1α and increased levels of apoptosis marker cleaved caspase 3, confirming in vivo efficacy. Furthermore, we confirmed that MO-2097 works effectively in cancer patient-based organoid models. CONCLUSION: MO-2097 represents a promising new generation of chemotherapeutic agents targeting HIF-1α inhibition via hnRNPA2B1, requiring further investigation.