RESUMEN
Glioblastoma (GBM) remains an incurable disease, requiring more effective therapies. Through interrogation of publicly available CRISPR and RNAi library screens, we identified the α-ketoglutarate dehydrogenase (OGDH) gene, which encodes an enzyme that is part of the tricarboxylic acid (TCA) cycle, as essential for GBM growth. Moreover, by combining transcriptome and metabolite screening analyses, we discovered that loss of function of OGDH by the clinically validated drug compound CPI-613 was synthetically lethal with Bcl-xL inhibition (genetically and through the clinically validated BH3 mimetic, ABT263) in patient-derived xenografts as well neurosphere GBM cultures. CPI-613-mediated energy deprivation drove an integrated stress response with an upregulation of the BH3-only domain protein, Noxa, in an ATF4-dependent manner, as demonstrated by genetic loss-of-function experiments. Consistently, silencing of Noxa attenuated cell death induced by CPI-613 in model systems of GBM. In patient-derived xenograft models of GBM in mice, the combination treatment of ABT263 and CPI-613 suppressed tumor growth and extended animal survival more potently than each compound on its own. Therefore, combined inhibition of Bcl-xL along with disruption of the TCA cycle might be a treatment strategy for GBM.
Asunto(s)
Compuestos de Anilina , Caprilatos , Glioblastoma , Complejo Cetoglutarato Deshidrogenasa , Sulfuros , Sulfonamidas , Mutaciones Letales Sintéticas , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína bcl-X , Animales , Humanos , Ratones , Factor de Transcripción Activador 4/metabolismo , Factor de Transcripción Activador 4/genética , Compuestos de Anilina/farmacología , Proteína bcl-X/metabolismo , Proteína bcl-X/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/tratamiento farmacológico , Línea Celular Tumoral , Ciclo del Ácido Cítrico/efectos de los fármacos , Glioblastoma/patología , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/tratamiento farmacológico , Complejo Cetoglutarato Deshidrogenasa/metabolismo , Complejo Cetoglutarato Deshidrogenasa/genética , Complejo Cetoglutarato Deshidrogenasa/antagonistas & inhibidores , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Sulfonamidas/farmacologíaRESUMEN
Although cold preservation remains the gold standard in organ transplantation, cold stress-induced cellular injury is a significant problem in clinical orthotopic liver transplantation (OLT). Because a recent study showed that cold stress activates ferroptosis, a form of regulated cell death, we investigated whether and how ferroptosis determines OLT outcomes in mice and humans. Treatment with ferroptosis inhibitor (ferrostatin-1) during cold preservation reduced lipid peroxidation (malondialdehyde; MDA), primarily in liver sinusoidal endothelial cells (LSECs), and alleviated ischemia/reperfusion injury in mouse OLT. Similarly, ferrostatin-1 reduced cell death in cold-stressed LSEC cultures. LSECs deficient in nuclear factor erythroid 2-related factor 2 (NRF2), a critical regulator of ferroptosis, were susceptible to cold stress-induced cell death, concomitant with enhanced endoplasmic reticulum (ER) stress and expression of mitochondrial Ca2+ uptake regulator (MICU1). Indeed, supplementing MICU1 inhibitor reduced ER stress, MDA expression, and cell death in NRF2-deficient but not WT LSECs, suggesting NRF2 is a critical regulator of MICU1-mediated ferroptosis. Consistent with murine data, enhanced liver NRF2 expression reduced MDA levels, hepatocellular damage, and incidence of early allograft dysfunction in human OLT recipients. This translational study provides a clinically applicable strategy in which inhibition of ferroptosis during liver cold preservation mitigates OLT injury by protecting LSECs from peritransplant stress via an NRF2-regulatory mechanism.
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Ciclohexilaminas , Ferroptosis , Trasplante de Hígado , Fenilendiaminas , Ratones , Humanos , Animales , Trasplante de Hígado/efectos adversos , Células Endoteliales/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Respuesta al Choque por Frío , Hígado/metabolismo , Proteínas de Unión al Calcio/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/metabolismoRESUMEN
In metabolically active tumors, responses of cells to drugs are heavily influenced by oxygen availability via the surrounding vasculature alongside the extracellular matrix signaling. The objective of this study is to investigate hepatotoxicity by replicating critical features of hepatocellular carcinoma (HCC). This includes replicating 3D structures, metabolic activities, and tumor-specific markers. The internal environment of spheroids comprised of cancerous human patient-derived hepatocytes using microparticles is modulated to enhance the oxygenation state and recreate cell-extracellular matrix interactions. Furthermore, the role of hepatic stellate cells in maintaining hepatocyte survival and function is explored and hepatocytes from two cellular sources (immortalized and patient-derived) to create four formulations with and without microparticles are utilized. To investigate drug-induced changes in metabolism and apoptosis in liver cells, coculture spheroids with and without microparticles are exposed to three hepatotoxic drugs. The use of microparticles increases levels of apoptotic markers in both liver models under drug treatments. This coincides with reduced levels of anti-apoptotic proteins and increased levels of pro-apoptotic proteins. Moreover, cells from different origins undergo apoptosis through distinct apoptotic pathways in response to identical drugs. This 3D microphysiological system offers a viable tool for liver cancer research to investigate mechanisms of apoptosis under different microenvironmental conditions.
Asunto(s)
Carcinoma Hepatocelular , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Técnicas de Cocultivo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Línea CelularRESUMEN
Background: Cancer multidrug resistance (MDR) is an important factor that severely affects the chemotherapeutic efficacy. Among various methods to bypass MDR, usage of cytokines, such as tumor necrosis factor alpha (TNFα) is attractive, which exerts antitumor effects of immunotherapeutic response and apoptotic/proinflammatory pathways. Nevertheless, the challenges remain how to implement targeted delivery of TNFα to reduce toxicity and manifest the involved signaling mechanism that subdues MDR. Methods: We synthesized a multifunctional nanosytem, in which TNFα covalently bound to doxorubicin (Dox)-loaded pH-responsive mesoporous silica nanoparticles (MSN) through bi-functional polyethylene glycol (TNFα-PEG-MSN-Hydrazone-Dox) as a robust design to overcome MDR. Results: The salient features of this nanoplatform are: 1) by judicious tailoring of TNFα concentration conjugated on MSN, we observed it could lead to a contrary effect of either proliferation or suppression of tumor growth; 2) the MSN-TNFα at higher concentration serves multiple functions, besides tumor targeting and inducer of apoptosis through extrinsic pathway, it inhibits the expression level of p-glycoprotein (P-gp), a cell membrane protein that functions as a drug efflux pump; 3) the enormous surface area of MSN provides for TNFα functionalization, and the nanochannels accommodate chemotherapeutics, Dox; 4) targeted intracellular release of Dox through the pH-dependent cleavage of hydrazone bonds induces apoptosis by the specific intrinsic pathway; and 5) TNFα-PEG-MSN-Hydrazone-Dox (MSN-Dox-TNFα) could infiltrate deep into the 3D spheroid tumor model through disintegration of tight junction proteins. When administered intratumorally in a Dox-resistant mouse tumor model, MSN-Dox-TNFα exhibited a synergistic therapeutic effect through the collective performances of TNFα and Dox. Conclusion: We hereby develop and demonstrate a multifunctional MSN-Dox-TNFα system with concentration-tailored TNFα that can abrogate the drug resistance mechanism, and significantly inhibit the tumor growth through both intrinsic and extrinsic apoptosis pathways, thus making it a highly potential nanomedicine translated in the treatment of MDR tumors.
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Nanopartículas , Neoplasias , Ratones , Animales , Citocinas , Factor de Necrosis Tumoral alfa , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Doxorrubicina , Apoptosis , Resistencia a Múltiples Medicamentos , Nanopartículas/química , Proliferación Celular , Hidrazonas/farmacología , Hidrazonas/uso terapéutico , Dióxido de Silicio/química , Resistencia a Antineoplásicos , PorosidadRESUMEN
Peptides are being increasingly important for subcellular targeted cancer treatment to improve specificity and reverse multidrug resistance. However, there has been yet any report on targeting plasma membrane (PM) through self-assembling peptides. A simple synthetic peptidic molecule (tF4) is developed. It is revealed that tF4 is carboxyl esterase-resistant and self-assembles into vesical nanostructures. Importantly, tF4 assemblies interact with PM through orthogonal hydrogen bonding and hydrophobic interaction to regulate cancer cellular functions. Mechanistically, tF4 assemblies induce stress fiber formation, cytoskeleton reconstruction, and death receptor 4/5 (DR4/5) expression in cancer cells. DR4/5 triggers extrinsic caspase-8 signaling cascade, resulting in cell death. The results provide a new strategy for developing enzyme-resistant and PM-targeting peptidic molecules against cancer.
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Nanoestructuras , Neoplasias , Línea Celular Tumoral , Membrana Celular/metabolismo , Péptidos/química , Muerte Celular , Nanoestructuras/química , Apoptosis , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismoRESUMEN
Biosynthesis has become a diverse toolbox for the development of bioactive molecules and materials, particularly for enzyme-induced modification and assembly of peptides. However, intracellular spatiotemporal regulation of artificial biomolecular aggregates based on neuropeptide remains challenging. Here, an enzyme responsive precursor (Y1 L-KGRR-FF-IR) is developed based on the neuropeptide Y Y1 receptor ligand, which self-assembles into nanoscale assemblies in the lysosomes and subsequently has an appreciable destructive effect on the mitochondria and cytoskeleton, resulting in breast cancer cell apoptosis. More importantly, in vivo studies reveal that Y1 L-KGRR-FF-IR has a good therapeutic effect, reduces breast cancer tumor volume and generates excellent tracer efficacy in lung metastasis models. This study provides a novel strategy for stepwise targeting and precise regulation of tumor growth inhibition through functional neuropeptide Y-based artificial aggregates for intracellular spatiotemporal regulation.
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Neoplasias de la Mama , Neuropéptidos , Humanos , Femenino , Neuropéptido Y/química , Neuropéptido Y/farmacología , Receptores de Neuropéptido Y , Apoptosis , MitocondriasRESUMEN
Targeted therapies such as venetoclax (VEN) (Bcl-2 inhibitor) have revolutionized the treatment of chronic lymphocytic leukemia (CLL). We previously reported that persister CLL cells in treated patients overexpress multiple antiapoptotic proteins and display resistance to proapoptotic agents. Here, we demonstrated that multidrug-resistant CLL cells in vivo exhibited apoptosis restriction at a pre-mitochondrial level due to insufficient activation of the Bax and Bak (Bax/Bak) proteins. Co-immunoprecipitation analyses with selective BH domain antagonists revealed that the pleiotropic proapoptotic protein (Bim) was prevented from activating Bax/Bak by "switching" interactions to other upregulated antiapoptotic proteins (Mcl-1, Bcl-xL, Bcl-2). Hence, treatments that bypass Bax/Bak restriction are required to deplete these resistant cells in patients. Protein phosphatase 2A (PP2A) contributes to oncogenesis and treatment resistance. We observed that small-molecule activator of PP2A (SMAP) induced cytotoxicity in multiple cancer cell lines and CLL samples, including multidrug-resistant leukemia and lymphoma cells. The SMAP (DT-061) activated apoptosis in multidrug-resistant CLL cells through induction of mitochondrial permeability transition pores, independent of Bax/Bak. DT-061 inhibited the growth of wild-type and Bax/Bak double-knockout, multidrug-resistant CLL cells in a xenograft mouse model. Collectively, we discovered multidrug-resistant CLL cells in patients and validated a pharmacologically tractable pathway to deplete this reservoir.
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Leucemia Linfocítica Crónica de Células B , Humanos , Animales , Ratones , Proteína X Asociada a bcl-2/metabolismo , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/metabolismo , Proteína Fosfatasa 2/genética , Proteína 1 de la Secuencia de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2 , Apoptosis/fisiología , Proteínas Reguladoras de la Apoptosis/metabolismo , Resistencia a Múltiples MedicamentosRESUMEN
Prostate cancer (PCa) is known as one of the most prevalent malignancies globally and is not yet curable owing to its progressive nature. It has been well documented that Genetic and epigenetic alterations maintain mandatory roles in PCa development. Apoptosis, a form of programmed cell death, has been shown to be involved in a number of physiological processes. Apoptosis disruption is considered as one of the main mechanism involved in lots of pathological conditions, especially malignancy. There is ample of evidence in support of the fact that microRNAs (miRNAs) have crucial roles in several cellular biological processes, including apoptosis. Escaping from apoptosis is a common event in malignancy progression. Emerging evidence revealed miRNAs capabilities to act as apoptotic or anti-apoptotic factors by altering the expression levels of tumor inhibitor or oncogene genes. In the present narrative review, we described in detail how apoptosis dysfunction could be involved in PCa processes and additionally, the mechanisms behind miRNAs affect the apoptosis pathways in PCa. Identifying the mechanisms behind the effects of miRNAs and their targets on apoptosis can provide scientists new targets for PCa treatment.
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MicroARNs , Neoplasias de la Próstata , Masculino , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Neoplasias de la Próstata/patología , Oncogenes , Apoptosis/genética , Regulación Neoplásica de la Expresión Génica/genética , Proliferación CelularRESUMEN
Patients with progressive fibrosing interstitial lung diseases (PF-ILDs) carry a poor prognosis and have limited therapeutic options. A hallmark feature is fibroblast resistance to apoptosis, leading to their persistence, accumulation, and excessive deposition of extracellular matrix. A complex balance of the B cell lymphoma 2 (BCL-2) protein family controlling the intrinsic pathway of apoptosis and fibroblast reliance on antiapoptotic proteins has been hypothesized to contribute to this resistant phenotype. Examination of lung tissue from patients with PF-ILD (idiopathic pulmonary fibrosis and silicosis) and mice with PF-ILD (repetitive bleomycin and silicosis) showed increased expression of antiapoptotic BCL-2 family members in α-smooth muscle actin-positive fibroblasts, suggesting that fibroblasts from fibrotic lungs may exhibit increased susceptibility to inhibition of antiapoptotic BCL-2 family members BCL-2, BCL-XL, and BCL-W with the BH3 mimetic ABT-263. We used 2 murine models of PF-ILD to test the efficacy of ABT-263 in reversing established persistent pulmonary fibrosis. Treatment with ABT-263 induced fibroblast apoptosis, decreased fibroblast numbers, and reduced lung collagen levels, radiographic disease, and histologically evident fibrosis. Our studies provide insight into how fibroblasts gain resistance to apoptosis and become sensitive to the therapeutic inhibition of antiapoptotic proteins. By targeting profibrotic fibroblasts, ABT-263 offers a promising therapeutic option for PF-ILDs.
Asunto(s)
Fibrosis Pulmonar Idiopática , Enfermedades Pulmonares Intersticiales , Silicosis , Ratones , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Fibrosis Pulmonar Idiopática/patología , Apoptosis/genética , Enfermedades Pulmonares Intersticiales/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Fibroblastos/metabolismo , Silicosis/metabolismoRESUMEN
The molecular mediators of cell death and inflammation in Alzheimer's disease (AD) have yet to be fully elucidated. Caspase-8 is a critical regulator of several cell death and inflammatory pathways; however, its role in AD pathogenesis has not yet been examined in detail. In the absence of caspase-8, mice are embryonic lethal due to excessive receptor interacting protein kinase 3-dependent (RIPK3-dependent) necroptosis. Compound RIPK3 and caspase-8 mutants rescue embryonic lethality, which we leveraged to examine the roles of these pathways in an amyloid ß-mediated (Aß-mediated) mouse model of AD. We found that combined deletion of caspase-8 and RIPK3, but not RIPK3 alone, led to diminished Aß deposition and microgliosis in the mouse model of AD carrying human presenilin 1 and amyloid precursor protein with 5 familial AD mutations (5xFAD). Despite its well-known role in cell death, caspase-8 did not appear to affect cell loss in the 5xFAD model. In contrast, we found that caspase-8 was a critical regulator of Aß-driven inflammasome gene expression and IL-1ß release. Interestingly, loss of RIPK3 had only a modest effect on disease progression, suggesting that inhibition of necroptosis or RIPK3-mediated cytokine pathways is not critical during midstages of Aß amyloidosis. These findings suggest that therapeutics targeting caspase-8 may represent a novel strategy to limit Aß amyloidosis and neuroinflammation in AD.
Asunto(s)
Enfermedad de Alzheimer , Amiloidosis , Animales , Humanos , Ratones , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/metabolismo , Caspasa 8/metabolismo , Modelos Animales de Enfermedad , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismoRESUMEN
Protection of the brain from viral infections involves the type I IFN (IFN-I) system, defects in which render humans susceptible to herpes simplex encephalitis (HSE). However, excessive cerebral IFN-I levels lead to pathologies, suggesting the need for tight regulation of responses. Based on data from mouse models, human HSE cases, and primary cell culture systems, we showed that microglia and other immune cells undergo apoptosis in the HSV-1-infected brain through a mechanism dependent on the cyclic GMP-AMP synthase/stimulator of interferon genes (cGAS/STING) pathway, but independent of IFN-I. HSV-1 infection of microglia induced cGAS-dependent apoptosis at high viral doses, whereas lower viral doses led to IFN-I responses. Importantly, inhibition of caspase activity prevented microglial cell death and augmented IFN-I responses. Accordingly, HSV-1-infected organotypic brain slices or mice treated with a caspase inhibitor exhibited lower viral load and an improved infection outcome. Collectively, we identify an activation-induced apoptosis program in brain immune cells that downmodulates local immune responses.
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Encéfalo/inmunología , Herpes Simple/inmunología , Herpesvirus Humano 1/inmunología , Interferón Tipo I/inmunología , Proteínas de la Membrana/inmunología , Nucleotidiltransferasas/inmunología , Animales , Apoptosis/genética , Apoptosis/inmunología , Encéfalo/virología , Herpes Simple/genética , Humanos , Interferón Tipo I/genética , Masculino , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Microglía/inmunología , Microglía/virología , Nucleotidiltransferasas/genéticaRESUMEN
Caspase-8 (CASP8) is one of the most frequently mutated genes in head and neck squamous carcinomas (HNSCCs), and CASP8 mutations are associated with poor survival. The distribution of these mutations in HNSCCs suggests that they are likely to be inactivating. Inhibition of CASP8 has been reported to sensitize cancer cells to necroptosis, a regulated cell death mechanism. Here, we show that knockdown of CASP8 renders HNSCCs susceptible to necroptosis by a second mitochondria-derived activator of caspase (SMAC) mimetic, birinapant, in combination with pan-caspase inhibitors Z-VAD-FMK or emricasan and radiation. In a syngeneic mouse model of oral cancer, birinapant, particularly when combined with radiation, delayed tumor growth and enhanced survival under CASP8 loss. Exploration of molecular underpinnings of necroptosis sensitivity confirmed that the level of functional receptor-interacting serine/threonine protein kinase 3 (RIP3) determines susceptibility to this mode of death. Although an in vitro screen revealed that low RIP3 levels rendered many HNSCC cell lines resistant to necroptosis, patient tumors maintained RIP3 expression and should therefore remain sensitive. Collectively, these results suggest that targeting the necroptosis pathway with SMAC mimetics, especially in combination with radiation, may be relevant therapeutically in HNSCC with compromised CASP8 status, provided that RIP3 function is maintained.
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Caspasa 8/metabolismo , Necroptosis/fisiología , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/metabolismo , Biomimética , Caspasa 8/genética , Caspasa 8/fisiología , Inhibidores de Caspasas/metabolismo , Inhibidores de Caspasas/farmacología , Caspasas/metabolismo , Línea Celular Tumoral , Bases de Datos Genéticas , Dipéptidos/metabolismo , Dipéptidos/farmacología , Humanos , Indoles/metabolismo , Indoles/farmacología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Necroptosis/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genéticaRESUMEN
RAS-RAF pathway presents a valuable target for the cancer treatment due to its important roles in the regulation of tumor proliferation, apoptosis and the obtained resistance. To explore such target a RAS/CRAF interference agent, was therefore conjugated with Pt(IV) prodrugs via ester bond, resulting in total eleven multifunctional Pt(IV) complexes. The complexes could target genomic DNA and disrupt the signaling transduction from RAS protein to CRAF so that block the mitogen-activated protein kinase (MAPK) signaling pathway. Experiments in vitro indicated that all of the Pt(IV) complexes showed potent anti-tumor activity with IC50 values ranged from 8 nM to 22.55 µM, which were significantly improved as compared with cisplatin (CDDP) whose IC50 values ranged from 5.45 µM to 9.05 µM. Among them, 26 exerted the best anti-tumor activity in vitro, which not only exhibited excellent cytotoxicity against normal tumor cells, but also against CDDP-resistance cell lines (e.g. A549/CDDP and SKOV-3/CDDP). Importantly, 26 only showed little effect on normal cell lines such as HUEVC and LO2. Besides, the following biological mechanisms studies demonstrated that 26 could efficiently enter. A549 cells, significantly arrest cell cycle at G2/M phase, disrupt the signaling pathway and trigger endogenous caspase apoptosis pathway. Furthermore, results of a xenograft subcutaneous model of A549 tumor showed that 26 could effectively decrease tumor growth rates without causing loss of bodyweight.
Asunto(s)
Antineoplásicos/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Glicina/análogos & derivados , Compuestos Organoplatinos/farmacología , Sulfonas/farmacología , Quinasas raf/antagonistas & inhibidores , Proteínas ras/antagonistas & inhibidores , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Cisplatino/farmacología , Daño del ADN , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Glicina/química , Glicina/farmacología , Humanos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Estructura Molecular , Compuestos Organoplatinos/síntesis química , Compuestos Organoplatinos/química , Especies Reactivas de Oxígeno/análisis , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal/efectos de los fármacos , Relación Estructura-Actividad , Sulfonas/química , Quinasas raf/metabolismo , Proteínas ras/metabolismoRESUMEN
Hepatic inflammasome activation is considered a major contributor to liver fibrosis in NASH. Apoptosis signal-regulating kinase 1 (ASK1) is an apical mitogen-activated protein kinase that activates hepatic JNK and p38 to promote apoptosis, inflammation, and fibrosis. The aim of the current study was to investigate whether pharmacologic inhibition of ASK1 could attenuate hepatic fibrosis driven by inflammasome activation using gain-of-function NOD-like receptor protein 3 (Nlrp3) mutant mice. Tamoxifen-inducible Nlrp3 knock-in (Nlrp3A350V/+CreT-KI) mice and WT mice were administered either control chow diet or diet containing the selective ASK1 inhibitor GS-444217 for 6 weeks. Livers of Nlrp3-KI mice had increased inflammation, cell death, and fibrosis and increased phosphorylation of ASK1, p38, and c-Jun. GS-444217 reduced ASK1 pathway activation, liver cell death, and liver fibrosis. ASK1 inhibition resulted in a significant downregulation of genes involved in collagen production and extracellular matrix deposition, as well as in a reduced hepatic TNF-α expression. ASK1 inhibition also directly reduced LPS-induced gene expression of Collagen 1A1 (Col1a1) in hepatic stellate cells isolated from Nlrp3-KI mice. In conclusion, ASK1 inhibition reduced liver cell death and fibrosis downstream of inflammatory signaling induced by NLRP3. These data provide mechanistic insight into the antifibrotic mechanisms of ASK1 inhibition.
Asunto(s)
Muerte Celular/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Cirrosis Hepática/metabolismo , Hígado/lesiones , Hígado/metabolismo , MAP Quinasa Quinasa Quinasa 5/efectos de los fármacos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Administración Oral , Animales , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Cadena alfa 1 del Colágeno Tipo I , Inhibidores Enzimáticos/administración & dosificación , Femenino , Regulación de la Expresión Génica , Células Estrelladas Hepáticas/metabolismo , Inflamasomas/metabolismo , Inflamación/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Cirrosis Hepática/patología , MAP Quinasa Quinasa Quinasa 5/genética , MAP Quinasa Quinasa Quinasa 5/metabolismo , Masculino , Ratones , Ratones Endogámicos NOD , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Fosforilación , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Chemotherapy-induced peripheral neuropathy is one of the most prevalent dose-limiting toxicities of anticancer therapy. Development of effective therapies to prevent chemotherapy-induced neuropathies could be enabled by a mechanistic understanding of axonal breakdown following exposure to neuropathy-causing agents. Here, we reveal the molecular mechanisms underlying axon degeneration induced by 2 widely used chemotherapeutic agents with distinct mechanisms of action: vincristine and bortezomib. We showed previously that genetic deletion of SARM1 blocks vincristine-induced neuropathy and demonstrate here that it also prevents axon destruction following administration of bortezomib in vitro and in vivo. Using cultured neurons, we found that vincristine and bortezomib converge on a core axon degeneration program consisting of nicotinamide mononucleotide NMNAT2, SARM1, and loss of NAD+ but engage different upstream mechanisms that closely resemble Wallerian degeneration after vincristine and apoptosis after bortezomib. We could inhibit the final common axon destruction pathway by preserving axonal NAD+ levels or expressing a candidate gene therapeutic that inhibits SARM1 in vitro. We suggest that these approaches may lead to therapies for vincristine- and bortezomib-induced neuropathies and possibly other forms of peripheral neuropathy.
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Proteínas del Dominio Armadillo/efectos de los fármacos , Proteínas del Dominio Armadillo/metabolismo , Axones/metabolismo , Bortezomib/farmacología , Proteínas del Citoesqueleto/efectos de los fármacos , Proteínas del Citoesqueleto/metabolismo , Degeneración Nerviosa/metabolismo , Vincristina/farmacología , Animales , Antineoplásicos/farmacología , Apoptosis , Proteínas del Dominio Armadillo/genética , Axones/patología , Proteínas del Citoesqueleto/genética , Quimioterapia , Femenino , Regulación Neoplásica de la Expresión Génica , Terapia Genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Degeneración Nerviosa/tratamiento farmacológico , Degeneración Nerviosa/genética , Degeneración Nerviosa/patología , Neuronas/metabolismo , Mononucleótido de Nicotinamida , Nicotinamida-Nucleótido AdenililtransferasaRESUMEN
Various physiological processes involve appropriate tissue developmental process and homeostasis - the pathogenesis of several diseases connected with deregulatory apoptosis process. Apoptosis plays a crucial role in maintaining a balance between cell death and division, evasion of apoptosis results in the uncontrolled multiplication of cells leading to different diseases such as cancer. Currently, the development of apoptosis targeting anticancer drugs has gained much interest since cell death induced by apoptosis causes minimal inflammation. The understanding of complexities of apoptosis mechanism and how apoptosis is evolved by tumor cells to oppose cell death has focused research into the new strategies designed to induce apoptosis in cancer cells. This review focused on the underlying mechanism of apoptosis and the dysregulation of apoptosis modulators involved in the extrinsic and intrinsic apoptotic pathway, which include death receptors (DRs) proteins, cellular FLICE inhibitory proteins (c-FLIP), anti-apoptotic Bcl-2 proteins, inhibitors of apoptosis proteins (IAPs), tumor suppressor (p53) in cancer cells along with various current clinical approaches aimed to selectively induce apoptosis in cancer cells.
RESUMEN
During developmental angiogenesis, blood vessels grow and remodel to ultimately build a hierarchical vascular network. Whether, how, cell death signaling molecules contribute to blood vessel formation is still not well understood. Caspase-8 (Casp-8), a key protease in the extrinsic cell death-signaling pathway, regulates cell death via both apoptosis and necroptosis. Here, we show that expression of Casp-8 in endothelial cells (ECs) is required for proper postnatal retina angiogenesis. EC-specific Casp-8-KO pups (Casp-8ECKO) showed reduced retina angiogenesis, as the loss of Casp-8 reduced EC proliferation, sprouting, and migration independently of its cell death function. Instead, the loss of Casp-8 caused hyperactivation of p38 MAPK downstream of receptor-interacting serine/threonine protein kinase 3 (RIPK3) and destabilization of vascular endothelial cadherin (VE-cadherin) at EC junctions. In a mouse model of oxygen-induced retinopathy (OIR) resembling retinopathy of prematurity (ROP), loss of Casp-8 in ECs was beneficial, as pathological neovascularization was reduced in Casp-8ECKO pups. Taking these data together, we show that Casp-8 acts in a cell death-independent manner in ECs to regulate the formation of the retina vasculature and that Casp-8 in ECs is mechanistically involved in the pathophysiology of ROP.
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Caspasa 8/metabolismo , Neovascularización Patológica , Neovascularización Fisiológica , Retina/embriología , Animales , Animales Recién Nacidos , Antígenos CD/metabolismo , Cadherinas/metabolismo , Muerte Celular , Movimiento Celular , Proliferación Celular , Células Endoteliales/metabolismo , Femenino , Células Endoteliales de la Vena Umbilical Humana , Humanos , Pulmón/embriología , Ratones , Ratones Noqueados , Necroptosis , Oxígeno/metabolismo , Fosforilación , Proteína Serina-Treonina Quinasas de Interacción con Receptores/genética , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Transducción de Señal , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
The possible association between the membrane-associated guanylate kinase with inverted domain structure-1 (MAGI1) and inflammation has been suggested, but the molecular mechanisms underlying this link, especially during atherogenesis, remain unclear. In endothelial cells (ECs) exposed to disturbed flow (d-flow), p90 ribosomal S6 kinase (p90RSK) bound to MAGI1, causing MAGI1-S741 phosphorylation and sentrin/SUMO-specific protease 2 T368 phosphorylation-mediated MAGI1-K931 deSUMOylation. MAGI1-S741 phosphorylation upregulated EC activation via activating Rap1. MAGI1-K931 deSUMOylation induced both nuclear translocation of p90RSK-MAGI1 and ATF-6-MAGI1 complexes, which accelerated EC activation and apoptosis, respectively. Microarray screening revealed key roles for MAGI1 in the endoplasmic reticulum (ER) stress response. In this context, MAGI1 associated with activating transcription factor 6 (ATF-6). MAGI1 expression was upregulated in ECs and macrophages found in atherosclerotic-prone regions of mouse aortas as well as in the colonic epithelia and ECs of patients with inflammatory bowel disease. Further, reduced MAGI1 expression in Magi1-/+ mice inhibited d-flow-induced atherogenesis. In sum, EC activation and ER stress-mediated apoptosis are regulated in concert by two different types of MAGI1 posttranslational modifications, elucidating attractive drug targets for chronic inflammatory disease, particularly atherosclerosis.
Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Aterosclerosis/patología , Moléculas de Adhesión Celular/metabolismo , Estrés del Retículo Endoplásmico , Guanilato-Quinasas/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Factor de Transcripción Activador 6/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Adulto , Animales , Aorta/citología , Aorta/patología , Apoptosis , Moléculas de Adhesión Celular/genética , Células Cultivadas , Colon/citología , Colon/patología , Cisteína Endopeptidasas/metabolismo , Modelos Animales de Enfermedad , Células Endoteliales/patología , Endotelio Vascular/citología , Endotelio Vascular/patología , Femenino , Guanilato-Quinasas/genética , Humanos , Mucosa Intestinal/citología , Mucosa Intestinal/patología , Masculino , Ratones , Persona de Mediana Edad , Fosforilación , Cultivo Primario de Células , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Transducción de Señal , SumoilaciónRESUMEN
With a special size and structure, nanoparticles (NPs) have excellent application prospects in various fields and are widely used in the biomedicine, cosmetics and chemical industries nowadays. However, there have been some reports on the biosafety of this new type of material, pointing out its cytotoxicity in inducing apoptosis. With different physicochemical properties in size, shape, surface charge, and ligand, NPs exhibit different biocompatibilities when interacting with different cells. Therefore, a comprehensive and deep study into the proapoptotic mechanism of NPs is necessary. In the present review, we summarize the NP-triggered apoptotic signal pathways in detail and highlight some important functional molecules involved. We hope our findings and perspectives provide a new direction for the sound development of nanotechnology in the future.
Asunto(s)
Apoptosis/efectos de los fármacos , Nanopartículas/toxicidad , Materiales Biocompatibles/toxicidad , Transporte Biológico , Línea Celular , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/fisiología , Humanos , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Tamaño de la Partícula , Especies Reactivas de Oxígeno/metabolismo , Transducción de Señal , Propiedades de SuperficieRESUMEN
Tumor relapse is the leading cause of death in breast cancer, largely due to the fact that recurrent tumors are frequently resistant to chemotherapy. We previously reported that downregulation of the proapoptotic protein Par-4 promotes tumor recurrence in genetically engineered mouse models of breast cancer recurrence. In the present study, we examined the mechanism and functional significance of Par-4 downregulation in recurrent tumors. We found that epithelial-to-mesenchymal transition (EMT) promotes epigenetic silencing of Par-4 in recurrent tumors. Par-4 silencing proceeded through binding of the EMT transcription factor Twist to the Par-4 promoter, where Twist induced a unique bivalent chromatin domain. This bivalent configuration conferred plasticity at the Par-4 promoter, and Par-4 silencing could be reversed with pharmacologic inhibitors of Ezh2 and HDAC1/2. Using an epigenome editing approach to reexpress Par-4 by specifically reversing the histone modifications found in recurrent tumors, we found that Par-4 reexpression sensitized recurrent tumors to chemotherapy in vitro and in vivo. Upon reexpression, Par-4 bound to the protein phosphatase PP1, caused widespread changes in phosphorylation of cytoskeletal proteins, and cooperated with microtubule-targeting drugs to induce mitotic defects. These results identify Twist-induced epigenetic silencing of Par-4 as a targetable axis that promotes chemoresistance in recurrent breast cancer.