ABSTRACT
Background: Histones have been associated with human diseases. However, the implication of extranuclear histone proteins and their potential mechanism in the pathophysiology of chronic rhinosinusitis (CRS) have not been thoroughly investigated. This study was designed to evaluate the role of histones in patients with CRS by comparing histone expression between patients and controls. Methods: Nasal polyp (NP) tissues were obtained, and their comprehensive gene expression profiles were investigated by microarray analysis. Differences in expression were verified by reverse transcriptase polymerase chain reaction and immunohistochemical staining. Cell culture and flow cytometry were used to evaluate the role of histones in the pathogenesis of polyps. Results: Significant differences in the microarray analysis were observed between the patient and control groups (P < 0.01). It was found by flow cytometry that the histone (H2BK) can promote cell apoptosis in NPs. Conclusion: Our results indicate that reduced expression of H2BK may contribute to the imbalance process of cell proliferation and apoptosis in CRS with NP.
Subject(s)
Nasal Polyps , Nose Diseases , Humans , Nasal Polyps/diagnosis , Nasal Polyps/therapy , Chronic DiseaseABSTRACT
Nonalcoholic fatty liver disease (NAFLD) is a growing epidemic and the most common cause of chronic liver disease worldwide. It consists of a spectrum of liver disorders ranging from simple steatosis to NASH which predisposes patients to further fibrosis, cirrhosis and even hepatocarcinoma. Despite much research, an approved treatment is still lacking. Finding new therapeutic targets has therefore been a main priority. Known as a main regulator of the lipid metabolism and highly expressed in the liver, the nuclear receptor peroxisome proliferator-activated receptor-α (PPARα) has been identified as an attractive therapeutic target. Since its expression is silenced by DNA hypermethylation in NAFLD patients, many research strategies have aimed to restore the expression of PPARα and its target genes involved in lipid metabolism. Although previously tested PPARα agonists did not ameliorate the disease, current research has shown that PPARα also interacts and regulates epigenetic DNMT1, JMJD3, TET and SIRT1 enzymes. Moreover, there is a growing body of evidence suggesting the orchestrating role of epigenetics in the development and progression of NAFLD. Therefore, current therapeutic strategies are shifting more towards epigenetic drugs. This review provides a concise overview of the epigenetic regulation of NAFLD with a focus on PPARα regulation and highlights recently identified epigenetic interaction partners of PPARα.
ABSTRACT
Plectranthus neochilus Schltr. (Lamiaceae) is a plant recently introduced in Cuba. Worldwide, it is an ethnomedicinal alternative for its use against microbial infections, but the Cuban population use the extracts to treat sleep disorders. To address this apparent incongruity, four collections (from different seasonal conditions in the year) of Cuban P. neochilus cultivars were analyzed in terms of their pharmacognostic characteristics. Three extracts using fresh and dried leaves were chemically and biologically characterized. UPLC-DAD-MS/MS analysis was performed to determine their chemical composition, while a panel of nine microorganisms was used to evaluate their antimicrobial activity. Finally, cytotoxic effects of different fractions were measured in three cell lines by the resazurin viability assay. In contrast to previously reported micro and macromorphological properties of P. neochilus, the leaves from the Cuban cultivars did not present glandular trichomes, nor did they produce quantifiable levels of essential oils. Moreover, aqueous extracts used by the population revealed no significant antimicrobial activity and were not cytotoxic. The three extracts showed a similar phytochemical composition, i.e., eight flavonoids, seven abietane diterpenes, and rosmarinic acid as the major constituent, most of them reported for the first time in this species. The low yield of essential oil, the absence of glandular trichomes, compounds with a high level of oxidation, and a moderate antimicrobial activity detected were the most distinctive pharmacognostic and biological characteristics of P. neochilus grown in Cuba. These aspects could explain its non-use as an antimicrobial.
ABSTRACT
In spite of the current advances and achievements in cancer treatments, colorectal cancer (CRC) persists as one of the most prevalent and deadly tumor types in both men and women worldwide. Drug resistance, adverse side effects and high rate of angiogenesis, metastasis and tumor relapse remain one of the greatest challenges in long-term management of CRC and urges need for new leads of anticancer drugs. We demonstrate that CRC treatment with the phytopharmaceutical mangiferin (MGF), a glucosylxanthone present in Mango tree stem bark and leaves (Mangifera Indica L.), induces dose-dependent tumor regression and decreases lung metastasis in a syngeneic immunocompetent allograft mouse model of murine CT26 colon carcinoma, which increases overall survival of mice. Antimetastatic and antiangiogenic MGF effects could be further validated in a wound healing in vitro model in human HT29 cells and in a matrigel plug implant mouse model. Interestingly, transcriptome pathway enrichment analysis demonstrates that MGF inhibits tumor growth, metastasis and angiogenesis by multi-targeting of mitochondrial oxidoreductase and fatty acid ß-oxidation metabolism, PPAR, SIRT, NFκB, Stat3, HIF, Wnt and GP6 signaling pathways. MGF effects on fatty acid ß-oxidation metabolism and carnitine palmitoyltransferase 1 (CPT1) protein expression could be further confirmed in vitro in human HT29 colon cells. In conclusion, antitumor, antiangiogenic and antimetastatic effects of MGF treatment hold promise to reduce adverse toxicity and to mitigate therapeutic outcome of colorectal cancer treatment by targeting mitochondrial energy metabolism in the tumor microenvironment.
ABSTRACT
The steroidal lactone withaferin A (WFA) is a dietary phytochemical, derived from Withania somnifera. It exhibits a wide range of biological properties, including immunomodulatory, anti-inflammatory, antistress, and anticancer activities. Here we investigated the effect of WFA on T-cell motility, which is crucial for adaptive immune responses as well as autoimmune reactions. We found that WFA dose-dependently (within the concentration range of 0.3-1.25 µM) inhibited the ability of human T-cells to migrate via cross-linking of the lymphocyte function-associated antigen-1 (LFA-1) integrin with its ligand, intercellular adhesion molecule 1 (ICAM-1). Coimmunoprecipitation of WFA interacting proteins and subsequent tandem mass spectrometry identified a WFA-interactome consisting of 273 proteins in motile T-cells. In particular, our data revealed significant enrichment of the zeta-chain-associated protein kinase 70 (ZAP70) and cytoskeletal actin protein interaction networks upon stimulation. Phospho-peptide mapping and kinome analysis substantiated kinase signaling downstream of ZAP70 as a key WFA target, which was further confirmed by bait-pulldown and Western immunoblotting assays. The WFA-ZAP70 interaction was disrupted by a disulfide reducing agent dithiothreitol, suggesting an involvement of cysteine covalent binding interface. In silico docking predicted WFA binding to ZAP70 at cystine 560 and 564 residues. These findings provide a mechanistic insight whereby WFA binds to and inhibits the ZAP70 kinase and impedes T-cell motility. We therefore conclude that WFA may be exploited to pharmacologically control host immune responses and potentially prevent autoimmune-mediated pathologies.
Subject(s)
Cell Movement/drug effects , Protein Kinases/metabolism , Signal Transduction/drug effects , T-Lymphocytes/drug effects , Withanolides/pharmacology , ZAP-70 Protein-Tyrosine Kinase/antagonists & inhibitors , Cells, Cultured , Humans , Intercellular Adhesion Molecule-1/metabolism , Lymphocyte Function-Associated Antigen-1/metabolism , Phosphorylation , T-Lymphocytes/cytology , T-Lymphocytes/enzymologyABSTRACT
Multiple myeloma (MM) is a hematological malignancy characterized by plasma cells' uncontrolled growth. The major barrier in treating MM is the occurrence of primary and acquired therapy resistance to anticancer drugs. Often, this therapy resistance is associated with constitutive hyperactivation of tyrosine kinase signaling. Novel covalent kinase inhibitors, such as the clinically approved BTK inhibitor ibrutinib (IBR) and the preclinical phytochemical withaferin A (WA), have, therefore, gained pharmaceutical interest. Remarkably, WA is more effective than IBR in killing BTK-overexpressing glucocorticoid (GC)-resistant MM1R cells. To further characterize the kinase inhibitor profiles of WA and IBR in GC-resistant MM cells, we applied phosphopeptidome- and transcriptome-specific tyrosine kinome profiling. In contrast to IBR, WA was found to reverse BTK overexpression in GC-resistant MM1R cells. Furthermore, WA-induced cell death involves covalent cysteine targeting of Hinge-6 domain type tyrosine kinases of the kinase cysteinome classification, including inhibition of the hyperactivated BTK. Covalent interaction between WA and BTK could further be confirmed by biotin-based affinity purification and confocal microscopy. Similarly, molecular modeling suggests WA preferably targets conserved cysteines in the Hinge-6 region of the kinase cysteinome classification, favoring inhibition of multiple B-cell receptors (BCR) family kinases. Altogether, we show that WA's promiscuous inhibition of multiple BTK family tyrosine kinases represents a highly effective strategy to overcome GC-therapy resistance in MM.
ABSTRACT
Introduction Nasal polyposis is a disease characterized by a mechanical dysfunction of the nasal mucosa, closely related to the unique makeup of its extracellular matrix, which develops as the result of an anomalous tissue remodeling process. Transforming growth factor beta 1 (TGF-ß1) is reduced not only in the nasal polypoid tissue, but also in the plasma of aspirin-intolerant patients. These patients exhibit an imbalance in the production of eicosanoids characterized by an increase in leukotrienes. Thus, it is important that the relationship between the production of leukotrienes and TGF-ß1 be assessed. Objective To evaluate the effects of the cysteinyl leukotriene (CysLT) receptor antagonist montelukast on the systemic production of TGF-ß1 in patients with nasal polyposis, with or without concomitant aspirin intolerance. Methods The sample comprised 48 individuals with diagnosis of nasal polyposis and 15 healthy controls for comparison of the baseline TGF-ß1 levels in the peripheral blood and after treatment with CysLT receptor antagonist montelukast in the nasal-polyposis group. Results There was no difference in the change in TGF-ß1 levels after the treatment with montelukast in the subgroup of patients with polyposis and asthma ( p = 0.82) and in the subgroup with polyposis, asthma, and aspirin intolerance ( p = 0.51). Conclusion we found no impact of the therapy with a leukotriene receptor blocker on the production of TGF-ß1, making the antileukotriene therapy a highly questionable choice for the treatment of nasal polyposis, particularly from the standpoint of seeking to modify the remodeling process in this disease.
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Despite modern therapeutic advances, the survival prospects of pancreatic cancer patients remain poor, due to chemoresistance and dysregulated oncogenic kinase signaling networks. We applied a novel kinome activity-mapping approach using biological peptide targets as phospho-sensors to identify vulnerable kinase dependencies for therapy sensitization by physical plasma. Ser/Thr-kinome specific activity changes were mapped upon induction of ferroptotic cell death in pancreatic tumor cells exposed to reactive oxygen and nitrogen species of plasma-treated water (PTW). This revealed a broad kinome activity response involving the CAMK, the AGC and CMGC family of kinases. This systems-level kinome network response supports stress adaptive switches between chemoresistant anti-oxidant responses of Kelch-like ECH-associated protein 1 (KEAP1)/Heme Oxygenase 1 (HMOX1) and ferroptotic cell death sensitization upon suppression of Nuclear factor (erythroid derived 2)-like 2 (NRF2) and Glutathione peroxidase 4 (GPX4). This is further supported by ex vivo experiments in the chicken chorioallantoic membrane assay, showing decreased GPX4 and Glutathione (GSH) expression as well as increased lipid peroxidation, along with suppressed BxPC-3 tumor growth in response to PTW. Taken all together, we demonstrate that plasma treated water-derived oxidants sensitize pancreatic cancer cells to ferroptotic cell death by targeting a NRF2-HMOX1-GPX4 specific kinase signaling network.
Subject(s)
NF-E2-Related Factor 2 , Pancreatic Neoplasms , Cell Death , Humans , Kelch-Like ECH-Associated Protein 1/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Oxidants , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/genetics , Reactive Oxygen Species/metabolismABSTRACT
Marine plants have become an inexhaustible reservoir of new phytopharmaceuticals for cancer treatment. We demonstrate in vitro/in vivo antitumor efficacy of a standardized polyphenol extract from the marine angiosperm Thalassia testudinum (TTE) in colon tumor cell lines (RKO, SW480, and CT26) and a syngeneic allograft murine colorectal cancer model. MTT assays revealed a dose-dependent decrease of cell viability of RKO, CT26, and SW480 cells upon TTE treatment with IC50 values of, respectively, 175, 115, and 60 µg/mL. Furthermore, TTE significantly prevented basal and bFGF-induced angiogenesis in the chicken chorioallantoic membrane angiogenesis assay. In addition, TTE suppressed bFGF-induced migration of endothelial cells in a wound closure assay. Finally, TTE treatment abrogated CT26 colorectal cancer growth and increased overall organism survival in a syngeneic murine allograft model. Corresponding transcriptome profiling and pathway analysis allowed for the identification of the mechanism of action for the antitumor effects of TTE. In line with our in vitro/in vivo results, TTE treatment triggers ATF4-P53-NFκB specific gene expression and autophagy stress pathways. This results in suppression of colon cancer cell growth, cell motility, and angiogenesis pathways in vitro and in addition promotes antitumor immunogenic cell death in vivo.
Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Cell Movement/drug effects , Colorectal Neoplasms/pathology , Hydrocharitaceae , Immunogenic Cell Death/drug effects , Neovascularization, Pathologic/pathology , Plant Extracts/therapeutic use , Animals , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Autophagy/drug effects , Autophagy/physiology , Cell Line, Tumor , Cell Movement/physiology , Colorectal Neoplasms/drug therapy , Colorectal Neoplasms/metabolism , Humans , Hydrocharitaceae/chemistry , Immunogenic Cell Death/physiology , Male , Mice , Mice, Inbred BALB C , Neovascularization, Pathologic/drug therapy , Neovascularization, Pathologic/metabolism , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Xenograft Model Antitumor Assays/methodsABSTRACT
Abstract Introduction Nasal polyposis is a disease characterized by a mechanical dysfunction of the nasal mucosa, closely related to the unique makeup of its extracellular matrix, which develops as the result of an anomalous tissue remodeling process. Transforming growth factor beta 1 (TGF-β1) is reduced not only in the nasal polypoid tissue, but also in the plasma of aspirin-intolerant patients. These patients exhibit an imbalance in the production of eicosanoids characterized by an increase in leukotrienes. Thus, it is important that the relationship between the production of leukotrienes and TGF-β1 be assessed. Objective To evaluate the effects of the cysteinyl leukotriene (CysLT) receptor antagonist montelukast on the systemic production of TGF-β1 in patients with nasal polyposis, with or without concomitant aspirin intolerance. Methods The sample comprised 48 individuals with diagnosis of nasal polyposis and 15 healthy controls for comparison of the baseline TGF-β1 levels in the peripheral blood and after treatment with CysLT receptor antagonist montelukast in the nasal-polyposis group. Results There was no difference in the change in TGF-β1 levels after the treatment with montelukast in the subgroup of patients with polyposis and asthma (p = 0.82) and in the subgroup with polyposis, asthma, and aspirin intolerance (p = 0.51). Conclusion we found no impact of the therapy with a leukotriene receptor blocker on the production of TGF-β1, making the antileukotriene therapy a highly questionable choice for the treatment of nasal polyposis, particularly from the standpoint of seeking to modify the remodeling process in this disease.
ABSTRACT
OBJECTIVE: Chronic Rhinosinusitis with Nasal Polyps (CRSwNP) is a disease that features a mechanical dysfunction involving chronic inflammation and altered tissue remodeling. In this study, we aim to evaluate the fibroblast morphology and its cellular traction force in primary fibroblasts cell cultures obtained from both healthy individuals (n=7) and patients with CRSwNP (n=8). METHODS: Using a Traction-force Microscopy we analyzed parameters of Force/Tension in fibroblasts cultures in both experimental groups. RESULTS: The analysis of the Projected Area of Cell revealed that fibroblasts derived from nasal mucosa of healthy individuals have an area on average 39.24% larger than the fibroblasts obtained from the nasal polyp tissue. We also observed that the parameters directly related to the force of the cell, Max Cumulative Force and Net Contractile Moment, presented a high Force/Tension per unit of area in the fibroblasts derived from the healthy nasal mucosa (on average 41% and 52.54% higher than the fibroblasts of the nasal polyp respectively). CONCLUSION: Our results demonstrate a cellular mechanism that may be associated with the mechanical dysfunction found in the Nasal Polyp tissue. The weak traction force of nasal polyp-derived fibroblast may, in lower dimensions, impact on the remodeling of nasal mucosa in CRSwNP.
Subject(s)
Biomechanical Phenomena , Fibroblasts/ultrastructure , Nasal Polyps/ultrastructure , Pseudopodia/ultrastructure , Case-Control Studies , Chronic Disease , Female , Fibroblasts/pathology , Fibroblasts/physiology , Humans , Male , Microscopy, Atomic Force , Microscopy, Phase-Contrast , Middle Aged , Nasal Polyps/pathology , Nasal Polyps/physiopathology , Primary Cell Culture , Pseudopodia/pathology , Rhinitis/pathology , Sinusitis/pathologyABSTRACT
Advanced metastatic melanoma, one of the most aggressive skin malignancies, is currently without reliable therapy. The process of angiogenesis is crucial for progression and metastasis of the majority of solid tumors including melanomas. Therefore, new therapies are urgently needed. Mangiferin is a naturally occurring glucosylxanthone which exerts many pharmacological activities against cancer-inflammation. However, the effect of mangiferin on metastasis and tumor growth of metastatic melanoma remains unclear. In this study, we demonstrate that mangiferin interferes with inflammation, lipid and calcium signaling which selectively inhibits multiple NFkB target genes including interleukin-6, tumor necrosis factor, interferon gamma, vascular endothelial growth factor receptor 2, plasminogen activator urokinase, matrix metalloprotease 19, C-C Motif Chemokine Ligand 2 and placental growth factor. This abrogates angiogenic and invasive processes and capillary tube formation of metastatic melanoma cells as well as human placental blood vessel explants in-vitro and blocks angiogenesis characteristic of the chicken egg chorioallantoic membrane assay and in melanoma syngeneic studies in vivo. The results obtained in this research illustrate promising anti-angiogenic effects of the natural glucosylxanthone mangiferin for further (pre)clinical studies in melanoma cancer patients.
Subject(s)
Angiogenesis Inhibitors/therapeutic use , Melanoma/drug therapy , Skin Neoplasms/drug therapy , Xanthones/therapeutic use , Angiogenesis Inhibitors/pharmacology , Humans , Melanoma/pathology , Skin Neoplasms/pathology , Xanthones/pharmacologyABSTRACT
Introduction The importance of our study lies in the fact that we have demonstrated the occurrence of mechanical dysfunction within polypoid tissues, which promotes the development of polyps in the nasal cavity. Objective To change the paradigm of nasal polyposis (NP). In this new conception, the chronic nasal inflammatory process that occurs in response to allergies, to pollution, to changes in the epithelial barrier, or to other factors is merely the trigger of the development of the disease in individuals with a genetic predisposition to an abnormal tissue remodeling process, which leads to a derangement of the mechanical properties of the nasal mucosa and, consequently, allows it to grow unchecked. Data Synthesis We propose a fundamentally new approach to intervening in the pathological process of NP, addressing biomechanical properties, fluid dynamics, and the concept of surface tension. Conclusion The incorporation of biomechanical knowledge into our understanding of NP provides a new perspective to help elucidate the physiology and the pathology of nasal polyps, and new avenues for the treatment and cure of NP.
ABSTRACT
T-Lymphocyte kinases are important checkpoints that control T-cell motility by regulating a diverse range of signal transduction pathways. The distinct configuration of kinase events in T-cell could be used to fingerprint the status of T-cells. However, only small fraction human kinases have been characterized so far and little is known about the dynamics of the kinome in motile T-cells. Although several direct and indirect strategies exist to characterize cellular kinase activities, such as RNA interference, antibody arrays, enzyme kinetics, and mass spectrometry, this chapter focuses on an alternative multiplex phosphopeptide array-based methodology, which allows the kinome-wide identification of hyper-activated kinases involved in the regulation of T-cell migration.
Subject(s)
Mass Spectrometry/methods , Phosphopeptides/analysis , Protein Kinases/metabolism , Proteome/analysis , T-Lymphocytes/cytology , T-Lymphocytes/metabolism , Cell Movement , Cells, Cultured , Humans , Phosphorylation , Signal TransductionABSTRACT
Introduction: The importance of our study lies in the fact that we have demonstrated the occurrence ofmechanical dysfunction within polypoid tissues, which promotes the development of polyps in the nasal cavity. Objective: To change the paradigm of nasal polyposis (NP). In this new conception, the chronic nasal inflammatory process that occurs in response to allergies, to pollution, to changes in the epithelial barrier, or to other factors is merely the trigger of the development of the disease in individuals with a genetic predisposition to an abnormal tissue remodeling process, which leads to a derangement of the mechanical properties of the nasal mucosa and, consequently, allows it to grow unchecked. Data: Synthesis We propose a fundamentally new approach to intervening in the pathological process of NP, addressing biomechanical properties, fluid dynamics, and the concept of surface tension. Conclusion: The incorporation of biomechanical knowledge into our understanding of NP provides a new perspective to help elucidate the physiology and the pathology of nasal polyps, and new avenues for the treatment and cure of NP (AU)
Subject(s)
Humans , Nasal Polyps/physiopathology , Nasal Polyps/pathology , Inflammation/physiopathology , Sinusitis/physiopathology , Biomechanical Phenomena , Brazil , Flow Mechanics , Chronic Disease , Edema/physiopathology , Extracellular Matrix/pathology , Hydrostatic Pressure , Nasal Mucosa/physiopathology , Nasal Mucosa/pathologyABSTRACT
BACKGROUND: Chronic rhinosinusitis with nasal polyposis (CRSwNP) is an inflammatory disease associated with lymphoid aggregates and local IgE production related to Staphylococcus aureus enterotoxins. T-follicular helper cells and their effector cytokine interleukin (IL)-21 play an important role in germinal center proliferation. METHODS: IL-21 was determined on the mRNA level by qPCR in nasal tissue of 3 groups of patients: control (n = 17), chronic rhinosinusitis without nasal polyposis (CRSsNP; n = 23), and CRSwNP (n = 35). The expression of IL-21 by CD4+ T cells was analyzed in tissue at baseline and after 24-h stimulation of tissue fragments with S. aureus enterotoxin B (SEB) using flow cytometry. Finally, human nasal IL-21+CXCR5+CD4+ T cells were isolated and coincubated with human blood naive B cells to investigate their functionality. RESULTS: IL-21 mRNA expression was increased in the CRSwNP group (p < 0.05) compared to the control group, and B-cell lymphoma-6 and B-lymphocyte-induced maturation protein-1 were upregulated in CRSwNP versus CRSsNP. Furthermore, SEB was able to increase IL-21 mRNA expression significantly (p < 0.01) in nasal polyps. Flow cytometry revealed that the source of IL-21 was predominantly CD4+ T cells and that IL-21+CD4+ T cells were significantly increased in polyp tissue and further increased after SEB stimulation. Finally, tissue CXCR5+CD4+ T cells derived from nasal polyp tissue were able to induce maturation of human naive B cells. CONCLUSIONS: IL-21- and IL-21-producing CD4+ T cells were increased in CRSwNP. In addition, SEB induced an increase in IL-21 and IL-21+CD4+ T cells, suggesting that S. aureus can modulate the function of Tfh cells in nasal polyps. We speculate that T-follicular helper cells and IL-21 are important in the pathophysiology of CRSwNP.
Subject(s)
Interleukins/metabolism , Nasal Polyps/immunology , Rhinitis/immunology , Sinusitis/immunology , Staphylococcal Infections/immunology , Staphylococcus aureus/immunology , T-Lymphocytes, Helper-Inducer/immunology , Adult , B-Lymphocytes/immunology , Cell Differentiation , Cells, Cultured , Chronic Disease , Enterotoxins/immunology , Female , Germinal Center/immunology , Humans , Immunoglobulin E/blood , Interleukins/genetics , Male , Middle Aged , Receptors, CXCR5/metabolismABSTRACT
Stroke represents one of the first causes of mortality and morbidity worldwide. We evaluated the therapeutic potential of a novel semi-synthetic spirosteroid sapogenin derivative "S15" in a transient middle cerebral artery occlusion (tMCAO) focal ischemia model in rat. S15-treated rats had significantly reduced infarct volumes and improved neurological functions at 24h post-reperfusion, compared with ischemia. Corresponding gene expression changes in brain were characterized by mRNA sequencing and qPCR approaches. Next, we applied geneset, pathway and transcription factor motif enrichment analysis to identify relevant signaling networks responsible for neuronal damage upon ischemia-reperfusion or neuroprotection upon pretreatment with S15. As expected, ischemia-reperfusion brain damage strongly modulates transcriptional programs associated with immune responses, increased differentiation of immune cells as well as reduced (cat)ion transport and synaptic activity. Interestingly, S15-dependent neuroprotection regulates inflammation-associated genes involved in phagosome specific resolution of tissue damage, chemotaxis and anti-inflammatory alternative activation of microglia. Altogether our transcriptome wide RNA sequencing and integrated pathway analysis provides new clues in the neuroprotective properties of a novel spirosteroid S15 or neuronal damage in rat brains subjected to ischemia, which opens new perspectives for successful treatment of stroke.
Subject(s)
Brain Ischemia/metabolism , Neuroprotective Agents/administration & dosage , Sapogenins/administration & dosage , Stroke/metabolism , Transcriptome , Animals , Brain Ischemia/drug therapy , Infarction, Middle Cerebral Artery/drug therapy , Infarction, Middle Cerebral Artery/metabolism , Rats, Wistar , Reperfusion Injury/drug therapy , Reperfusion Injury/metabolism , Stroke/drug therapyABSTRACT
Despite the worldwide research efforts to combat cancer, it remains a leading cause of death. Although various specific kinase inhibitors already have been approved for clinical cancer treatment, occurrence of intrinsic or acquired resistance and intermittent response over longer periods limits long-term success of single kinase-targeted therapies. In this respect, there is a renewed interest in polypharmaceutical natural compounds, which simultaneously target various hyperactivated kinases involved in tumour-inflammation, angiogenesis, cell survival, proliferation, metastasis and angiogenesis. The dietary medicinal phytochemical withaferin A (WA), isolated from Withaferin somnifera (popular Indian name Ashwagandha), holds promise as a novel anti-cancer agent, which targets multiple cell survival kinase pathways, including IκB kinase/NF-κB, PI3 kinase/protein kinase B/mammalian target of rapamycin and mitogen-activated protein kinase/extracellular signal-regulated kinase amongst others. In this review, we propose a novel mechanism of WA-dependent kinase inhibition via electrophilic covalent targeting of cysteine residues in conserved kinase activation domains (kinase cysteinome), which could underlie its pleiotropic therapeutic effects in cancer signalling.
Subject(s)
Neoplasms/drug therapy , Phytochemicals/pharmacology , Withanolides/pharmacology , Animals , Cell Cycle Checkpoints/drug effects , Cell Line, Tumor , Disease Models, Animal , Humans , Molecular Structure , Protein ConformationABSTRACT
Multiple myeloma (MM) is a hematological malignancy, which remains incurable because most patients eventually relapse or become refractory to current treatments. Due to heterogeneity within the cancer cell microenvironment, cancer cell populations employ a dynamic survival strategy to chemotherapeutic treatments, which frequently results in a rapid acquisition of therapy resistance. Besides resistance-conferring genetic alterations within a tumor cell population selected during drug treatment, recent findings also reveal non-mutational mechanisms of drug resistance, involving a small population of "cancer stem cells" (CSCs) which are intrinsically more refractory to the effects of a variety of anticancer drugs. Other studies have implicated epigenetic mechanisms in reversible drug tolerance to protect the population from eradication by potentially lethal exposures, suggesting that acquired drug resistance does not necessarily require a stable heritable genetic alteration. Clonal evolution of MM cells and the bone marrow microenvironment changes contribute to drug resistance. MM-CSCs may not be a static population and survive as phenotypically and functionally different cell types via the transition between stem-like and non-stem-like states in local microenvironments, as observed in other types of cancers. Targeting MM-CSCs is clinically relevant, and different approaches have been suggested to target molecular, metabolic and epigenetic signatures, and the self-renewal signaling characteristic of MM CSC-like cells. Here, we summarize epigenetic strategies to reverse drug resistance in heterogeneous multiple myeloma.