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2.
Nat Cell Biol ; 26(4): 613-627, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429478

RESUMO

The ability of tumour cells to thrive in harsh microenvironments depends on the utilization of nutrients available in the milieu. Here we show that pancreatic cancer-associated fibroblasts (CAFs) regulate tumour cell metabolism through the secretion of acetate, which can be blocked by silencing ATP citrate lyase (ACLY) in CAFs. We further show that acetyl-CoA synthetase short-chain family member 2 (ACSS2) channels the exogenous acetate to regulate the dynamic cancer epigenome and transcriptome, thereby facilitating cancer cell survival in an acidic microenvironment. Comparative H3K27ac ChIP-seq and RNA-seq analyses revealed alterations in polyamine homeostasis through regulation of SAT1 gene expression and enrichment of the SP1-responsive signature. We identified acetate/ACSS2-mediated acetylation of SP1 at the lysine 19 residue that increased SP1 protein stability and transcriptional activity. Genetic or pharmacologic inhibition of the ACSS2-SP1-SAT1 axis diminished the tumour burden in mouse models. These results reveal that the metabolic flexibility imparted by the stroma-derived acetate enabled cancer cell survival under acidosis via the ACSS2-SP1-SAT1 axis.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Pancreáticas , Animais , Camundongos , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Acetatos/farmacologia , Acetatos/metabolismo , Neoplasias Pancreáticas/genética , Poliaminas , Microambiente Tumoral
3.
Proc Natl Acad Sci U S A ; 120(34): e2215095120, 2023 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-37585460

RESUMO

Cancer cachexia, and its associated complications, represent a large and currently untreatable roadblock to effective cancer management. Many potential therapies have been proposed and tested-including appetite stimulants, targeted cytokine blockers, and nutritional supplementation-yet highly effective therapies are lacking. Innovative approaches to treating cancer cachexia are needed. Members of the Kruppel-like factor (KLF) family play wide-ranging and important roles in the development, maintenance, and metabolism of skeletal muscle. Within the KLF family, we identified KLF10 upregulation in a multitude of wasting contexts-including in pancreatic, lung, and colon cancer mouse models as well as in human patients. We subsequently interrogated loss-of-function of KLF10 as a potential strategy to mitigate cancer associated muscle wasting. In vivo studies leveraging orthotopic implantation of pancreas cancer cells into wild-type and KLF10 KO mice revealed significant preservation of lean mass and robust suppression of pro-atrophy muscle-specific ubiquitin ligases Trim63 and Fbxo32, as well as other factors implicated in atrophy, calcium signaling, and autophagy. Bioinformatics analyses identified Transforming growth factor beta (TGF-ß), a known inducer of KLF10 and cachexia promoting factor, as a key upstream regulator of KLF10. We provide direct in vivo evidence that KLF10 KO mice are resistant to the atrophic effects of TGF-ß. ChIP-based binding studies demonstrated direct binding to Trim63, a known wasting-associated atrogene. Taken together, we report a critical role for the TGF-ß/KLF10 axis in the etiology of pancreatic cancer-associated muscle wasting and highlight the utility of targeting KLF10 as a strategy to prevent muscle wasting and limit cancer-associated cachexia.


Assuntos
Neoplasias Pancreáticas , Fator de Crescimento Transformador beta , Humanos , Camundongos , Animais , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Caquexia/genética , Atrofia Muscular/genética , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Músculo Esquelético/metabolismo , Fatores de Transcrição de Resposta de Crescimento Precoce/genética , Fatores de Transcrição de Resposta de Crescimento Precoce/metabolismo
4.
Commun Biol ; 6(1): 519, 2023 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-37179425

RESUMO

Cancer-induced muscle wasting reduces quality of life, complicates or precludes cancer treatments, and predicts early mortality. Herein, we investigate the requirement of the muscle-specific E3 ubiquitin ligase, MuRF1, for muscle wasting induced by pancreatic cancer. Murine pancreatic cancer (KPC) cells, or saline, were injected into the pancreas of WT and MuRF1-/- mice, and tissues analyzed throughout tumor progression. KPC tumors induces progressive wasting of skeletal muscle and systemic metabolic reprogramming in WT mice, but not MuRF1-/- mice. KPC tumors from MuRF1-/- mice also grow slower, and show an accumulation of metabolites normally depleted by rapidly growing tumors. Mechanistically, MuRF1 is necessary for the KPC-induced increases in cytoskeletal and muscle contractile protein ubiquitination, and the depression of proteins that support protein synthesis. Together, these data demonstrate that MuRF1 is required for KPC-induced skeletal muscle wasting, whose deletion reprograms the systemic and tumor metabolome and delays tumor growth.


Assuntos
Neoplasias Pancreáticas , Qualidade de Vida , Animais , Camundongos , Músculo Esquelético/metabolismo , Atrofia Muscular/genética , Pâncreas/metabolismo , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Neoplasias Pancreáticas
5.
J Cachexia Sarcopenia Muscle ; 14(3): 1424-1440, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36883680

RESUMO

BACKGROUND: Over the past decade, advances in sepsis identification and management have resulted in decreased sepsis mortality. This increase in survivorship has highlighted a new clinical obstacle: chronic critical illness (CCI), for which there are no effective treatment options. Up to half of sepsis survivors suffer from CCI, which can include multi-organ dysfunction, chronic inflammation, muscle wasting, physical and mental disabilities, and enhanced frailty. These symptoms prevent survivors from returning to regular day-to-day activities and are directly associated with poor quality of life. METHODS: Mice were subjected to cecal ligation and puncture (CLP) with daily chronic stress (DCS) as an in vivo model to study sepsis late-effects/sequelae on skeletal muscle components. Longitudinal monitoring was performed via magnetic resonance imaging, skeletal muscle and/or muscle stem cell (MuSCs) assays (e.g., post-necropsy wet muscle weights, minimum Feret diameter measurements, in vitro MuSC proliferation and differentiation, number of regenerating myofibres and numbers of Pax7-positive nuclei per myofibre), post-sepsis whole muscle metabolomics and MuSC isolation and high-content transcriptional profiling. RESULTS: We report several findings supporting the hypothesis that MuSCs/muscle regeneration are critically involved in post-sepsis muscle recovery. First, we show that genetic ablation of muscle stem cells (MuSCs) impairs post-sepsis muscle recovery (maintenance of 5-8% average lean mass loss compared with controls). Second, we observe impaired MuSCs expansion capacity and morphological defects at 26 days post-sepsis compared with control MuSCs (P < 0.001). Third, when subjected to an experimental muscle injury, sepsis-recovered mice exhibited evidence of impaired muscle regeneration compared with non-septic mice receiving the same muscle injury (CLP/DCS injured mean minimum Feret is 92.1% of control injured, P < 0.01). Fourth, we performed a longitudinal RNA sequencing study on MuSCs isolated from post-sepsis mice and found clear transcriptional differences in all post-sepsis samples compared with controls. At Day 28, CLP/DCS mice satellite cells have multiple altered metabolic pathways, such as oxidative phosphorylation, mitochondrial dysfunction, sirtuin signalling and oestrogen receptor signalling, compared with controls (P < 0.001). CONCLUSIONS: Our data show that MuSCs and muscle regeneration are required for effective post-sepsis muscle recovery and that sepsis triggers morphological, functional, and transcriptional changes in MuSCs. Moving forward, we strive to leverage a more complete understanding of post-sepsis MuSC/regenerative defects to identify and test novel therapies that promote muscle recovery and improve quality of life in sepsis survivors.


Assuntos
Células Satélites de Músculo Esquelético , Sepse , Camundongos , Animais , Qualidade de Vida , Músculo Esquelético/patologia , Células Satélites de Músculo Esquelético/metabolismo , Diferenciação Celular , Sepse/metabolismo
6.
Acta Neuropathol Commun ; 11(1): 20, 2023 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-36703211

RESUMO

Acquired sporadic late onset nemaline myopathy (SLONM) and inherited nemaline myopathy (iNM) both feature accumulation of nemaline rods in muscle fibers. Unlike iNM, SLONM is amenable to therapy. The distinction between these disorders is therefore crucial when the diagnosis remains ambiguous after initial investigations. We sought to identify biomarkers facilitating this distinction and to investigate the pathophysiology of nemaline rod formation in these different disorders. Twenty-two muscle samples from patients affected by SLONM or iNM underwent quantitative histological analysis, laser capture microdissection for proteomic analysis of nemaline rod areas and rod-free areas, and transcriptomic analysis. In all iNM samples, nemaline rods were found in subsarcolemmal or central aggregates, whereas they were diffusely distributed within muscle fibers in most SLONM samples. In SLONM, muscle fibers harboring nemaline rods were smaller than those without rods. Necrotic fibers, increased endomysial connective tissue, and atrophic fibers filled with nemaline rods were more common in SLONM. Proteomic analysis detected differentially expressed proteins between nemaline rod areas and rod-free areas, as well as between SLONM and iNM. These differentially expressed proteins implicated immune, structural, metabolic, and cellular processes in disease pathophysiology. Notably, immunoglobulin overexpression with accumulation in nemaline rod areas was detected in SLONM. Transcriptomic analysis corroborated proteomic findings and further revealed substantial gene expression differences between SLONM and iNM. Overall, we identified unique pathological and molecular signatures associated with SLONM and iNM, suggesting distinct underlying pathophysiological mechanisms. These findings represent a step towards enhanced diagnostic tools and towards development of treatments for SLONM.


Assuntos
Miopatias da Nemalina , Humanos , Miopatias da Nemalina/genética , Miopatias da Nemalina/patologia , Proteômica , Fibras Musculares Esqueléticas/patologia , Miocárdio/patologia , Músculo Esquelético/patologia
7.
Shock ; 58(1): 45-55, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35984760

RESUMO

ABSTRACT: Sepsis is a highly prevalent cause of death in intensive care units. Characterized by severe immune cell derangements, sepsis is often associated with multiorgan dysfunction. For many sepsis survivors, these deficits can persist long after clinical resolution of the underlying infection. Although many studies report on the impact of sepsis on individual immune cell subtypes, a comprehensive analysis of sepsis-induced alterations within and across the immune cell landscape is lacking. In this study, we used single-cell RNA sequencing to assess sepsis-associated transcriptional changes in immune cells isolated from bone marrow at single-cell resolution. We used a high-survival fecal-induced peritonitis sepsis model using Friend leukemia virus B mice. Single-cell RNA sequencing classified 3402 single cells from control subjects into 14 clusters representing long-term hematopoietic stem cell (HSC), short-term HSC, basophil, dendritic cell, eosinophil, erythroblast, erythrocyte, macrophage, neutrophil, natural killer cell, plasma cell, plasmacytoid dendritic cell, pre-B cell, and T memory cell lineages. One day following experimentally induced sepsis, cell type compositions shifted significantly and included notable decreases in HSC and myeloid cell abundance. In addition to proportional cell composition changes, acute sepsis induced significant transcriptional alterations in most immune cell types analyzed-changes that failed to completely resolve 1 month after sepsis. Taken together, we report widespread and persistent transcriptional changes in diverse immune cells in response to polymicrobial infection. This study will serve as a valuable resource for future work investigating acute and/or long-term sepsis-associated immune cell derangements.


Assuntos
Coinfecção , Peritonite , Sepse , Animais , Medula Óssea , Células da Medula Óssea , Células-Tronco Hematopoéticas , Humanos , Camundongos , Peritonite/complicações
8.
BioTech (Basel) ; 11(1)2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35822814

RESUMO

The research and development of non-viral gene therapy has been extensive over the past decade and has received a big push thanks to the recent successful approval of non-viral nucleic acid therapy products. Despite these developments, nucleic acid therapy applications in cancer have been limited. One of the main causes of this has been the imbalance in development of delivery vectors as compared with sophisticated nucleic acid payloads, such as siRNA, mRNA, etc. This paper reviews non-viral vectors that can be used to deliver nucleic acids for cancer treatment. It discusses various types of vectors and highlights their current applications. Additionally, it discusses a perspective on the current regulatory landscape to facilitate the commercial translation of gene therapy.

9.
Oncogene ; 41(7): 971-982, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35001076

RESUMO

Metabolic alterations regulate cancer aggressiveness and immune responses. Given the poor response of pancreatic ductal adenocarcinoma (PDAC) to conventional immunotherapies, we investigated the link between metabolic alterations and immunosuppression. Our metabolic enzyme screen indicated that elevated expression of CD73, an ecto-5'-nucleotidase that generates adenosine, correlates with increased aggressiveness. Correspondingly, we observed increased interstitial adenosine levels in tumors from spontaneous PDAC mouse models. Diminishing CD73 by genetic manipulations ablated in vivo tumor growth, and decreased myeloid-derived suppressor cells (MDSC) in orthotopic mouse models of PDAC. A high-throughput cytokine profiling demonstrated decreased GM-CSF in mice implanted with CD73 knockdowns. Furthermore, we noted increased IFN-γ expression by intratumoral CD4+ and CD8+ T cells in pancreatic tumors with CD73 knockdowns. Depletion of CD4+ T cells, but not CD8+ T cells abrogated the beneficial effects of decreased CD73. We also observed that splenic MDSCs from Nt5e knockdown tumor-bearing mice were incompetent in suppressing T cell activation in the ex vivo assays. Replenishing GM-CSF restored tumor growth in Nt5e knockout tumors, which was reverted by MDSC depletion. Finally, anti-CD73 antibody treatment significantly improved gemcitabine efficacy in orthotopic models. Thus, targeting the adenosine axis presents a novel therapeutic opportunity for improving the anti-tumoral immune response against PDAC.


Assuntos
Células Supressoras Mieloides
10.
JCI Insight ; 7(2)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-34874916

RESUMO

Approximately 80% of pancreatic cancer patients suffer from cachexia, and one-third die due to cachexia-related complications such as respiratory failure and cardiac arrest. Although there has been considerable research into cachexia mechanisms and interventions, there are, to date, no FDA-approved therapies. A major contributing factor for the lack of therapy options could be the failure of animal models to accurately recapitulate the human condition. In this study, we generated an aged model of pancreatic cancer cachexia to compare cachexia progression in young versus aged tumor-bearing mice. Comparative skeletal muscle transcriptome analyses identified 3-methyladenine (3-MA) as a candidate antiwasting compound. In vitro analyses confirmed antiwasting capacity, while in vivo analysis revealed potent antitumor effects. Transcriptome analyses of 3-MA-treated tumor cells implicated Perp as a 3-MA target gene. We subsequently (a) observed significantly higher expression of Perp in cancer cell lines compared with control cells, (b) noted a survival disadvantage associated with elevated Perp, and (c) found that 3-MA-associated Perp reduction inhibited tumor cell growth. Finally, we have provided in vivo evidence that survival benefits conferred by 3-MA administration are independent of its effect on tumor progression. Taken together, we report a mechanism linking 3-MA to Perp inhibition, and we further implicate Perp as a tumor-promoting factor in pancreatic cancer.


Assuntos
Adenina/análogos & derivados , Caquexia , Proteínas de Membrana , Músculo Esquelético , Neoplasias Pancreáticas , Adenina/metabolismo , Adenina/farmacologia , Fatores Etários , Animais , Autofagia/efeitos dos fármacos , Caquexia/etiologia , Caquexia/metabolismo , Caquexia/terapia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Perfilação da Expressão Gênica/métodos , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/metabolismo , Camundongos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/terapia
11.
Cancer Lett ; 491: 70-77, 2020 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-32735910

RESUMO

Cancer cachexia patients experience significant muscle wasting, which impairs the quality of life and treatment efficacy for patients. Skeletal muscle protein turnover is imparted by increased expression of ubiquitin-proteasome pathway components. Mitogen-activated protein kinases p38 and ERK have been shown to augment E3 ubiquitin ligase expression. Utilizing reverse-phase protein arrays, we identified pancreatic cancer cell-conditioned media-induced activation of JNK signaling in myotubes differentiated from C2C12 myoblasts. Inhibition of JNK signaling with SP600125 reduced cancer cell-conditioned media-induced myotube atrophy, myosin heavy chain protein turnover, and mRNA expression of cachexia-specific ubiquitin ligases Trim63 and Fbxo32. Furthermore, utilizing an orthotopic pancreatic cancer cachexia mouse model, we demonstrated that treatment of tumor-bearing mice with SP600125 improved longitudinal measurements of forelimb grip strength. Post-necropsy measurements demonstrated that SP600125 treatment rescued body weight, carcass weight, and gastrocnemius muscle weight loss without impacting tumor growth. JNK inhibitor treatment also rescued myofiber degeneration and reduced the muscle expression of Trim63 and Fbxo32. These data demonstrate that JNK signaling contributes to muscle wasting in cancer cachexia, and its inhibition has the potential to be utilized as an anti-cachectic therapy.


Assuntos
Caquexia/etiologia , Proteínas Quinases JNK Ativadas por Mitógeno/fisiologia , Sistema de Sinalização das MAP Quinases/fisiologia , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Neoplasias Pancreáticas/complicações , Animais , Antracenos/farmacologia , Antracenos/uso terapêutico , Caquexia/tratamento farmacológico , Caquexia/metabolismo , Linhagem Celular Tumoral , Feminino , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Camundongos , Fibras Musculares Esqueléticas/patologia , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo
12.
J Cachexia Sarcopenia Muscle ; 11(5): 1351-1363, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32643301

RESUMO

BACKGROUND: Persistent loss of skeletal muscle mass and function as well as altered fat metabolism are frequently observed in severe sepsis survivors. Studies examining sepsis-associated tissue dysfunction from the perspective of the tissue microenvironment are scarce. In this study, we comprehensively assessed transcriptional changes in muscle and fat at single-cell resolution following experimental sepsis induction. METHODS: Skeletal muscle and visceral white adipose tissue from control mice or mice 1 day or 1 month following faecal slurry-induced sepsis were used. Single cells were mechanically and enzymatically prepared from whole tissue, and viable cells were further isolated by fluorescence activated cell sorting. Droplet-based single-cell RNA-sequencing (scRNA-seq; 10× Genomics) was used to generate single-cell gene expression profiles of thousands of muscle and fat-resident cells. Bioinformatics analyses were performed to identify and compare individual cell populations in both tissues. RESULTS: In skeletal muscle, scRNA-seq analysis classified 1438 single cells into myocytes, endothelial cells, fibroblasts, mesenchymal stem cells, macrophages, neutrophils, T-cells, B-cells, and dendritic cells. In adipose tissue, scRNA-seq analysis classified 2281 single cells into adipose stem cells, preadipocytes, endothelial cells, fibroblasts, macrophages, dendritic cells, B-cells, T-cells, NK cells, and gamma delta T-cells. One day post-sepsis, the proportion of most non-immune cell populations was decreased, while immune cell populations, particularly neutrophils and macrophages, were highly enriched. Proportional changes of endothelial cells, neutrophils, and macrophages were validated using faecal slurry and cecal ligation and puncture models. At 1 month post-sepsis, we observed persistent enrichment/depletion of cell populations and further uncovered a cell-type and tissue-specific ability to return to a baseline transcriptomic state. Differential gene expression analyses revealed key genes and pathways altered in post-sepsis muscle and fat and highlighted the engagement of infection/inflammation and tissue damage signalling. Finally, regulator analysis identified gonadotropin-releasing hormone and Bay 11-7082 as targets/compounds that we show can reduce sepsis-associated loss of lean or fat mass. CONCLUSIONS: These data demonstrate persistent post-sepsis muscle and adipose tissue disruption at the single-cell level and highlight opportunities to combat long-term post-sepsis tissue wasting using bioinformatics-guided therapeutic interventions.


Assuntos
Tecido Adiposo , Músculo Esquelético , Sepse , Animais , Células Endoteliais , Feminino , Masculino , Camundongos , Sepse/etiologia , Transcriptoma
13.
J Exp Med ; 217(7)2020 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-32441762

RESUMO

Approximately one third of cancer patients die due to complexities related to cachexia. However, the mechanisms of cachexia and the potential therapeutic interventions remain poorly studied. We observed a significant positive correlation between SIRT1 expression and muscle fiber cross-sectional area in pancreatic cancer patients. Rescuing Sirt1 expression by exogenous expression or pharmacological agents reverted cancer cell-induced myotube wasting in culture conditions and mouse models. RNA-seq and follow-up analyses showed cancer cell-mediated SIRT1 loss induced NF-κB signaling in cachectic muscles that enhanced the expression of FOXO transcription factors and NADPH oxidase 4 (Nox4), a key regulator of reactive oxygen species production. Additionally, we observed a negative correlation between NOX4 expression and skeletal muscle fiber cross-sectional area in pancreatic cancer patients. Knocking out Nox4 in skeletal muscles or pharmacological blockade of Nox4 activity abrogated tumor-induced cachexia in mice. Thus, we conclude that targeting the Sirt1-Nox4 axis in muscles is an effective therapeutic intervention for mitigating pancreatic cancer-induced cachexia.


Assuntos
Caquexia/complicações , Caquexia/metabolismo , NADPH Oxidase 4/metabolismo , Neoplasias/complicações , Neoplasias/metabolismo , Transdução de Sinais , Sirtuína 1/metabolismo , Tecido Adiposo/patologia , Animais , Linhagem Celular , Linhagem Celular Tumoral , Modelos Animais de Doenças , Progressão da Doença , Fatores de Transcrição Forkhead/metabolismo , Células HEK293 , Humanos , Metaboloma/efeitos dos fármacos , Camundongos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , NF-kappa B/metabolismo , Oxirredução , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Estabilidade Proteica/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Resveratrol/farmacologia , Transdução de Sinais/efeitos dos fármacos , Síndrome de Emaciação/patologia
14.
Cancer Lett ; 484: 29-39, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32344015

RESUMO

Incidence of cachexia is highly prevalent in pancreatic ductal adenocarcinoma (PDAC); advanced disease stage directly correlates with decreased muscle and fat mass in PDAC patients. The pancreatic tumor microenvironment is central to the release of systemic factors that govern lipolysis, proteolysis, and muscle and fat degeneration leading to the cachectic phenotype in cancer patients. The current study explores the role of macrophages, a key immunosuppressive player in the pancreatic tumor microenvironment, in regulating cancer cachexia. We observed a negative correlation between CD163-positive macrophage infiltration and muscle-fiber cross sectional area in human PDAC patients. To investigate the role of macrophages in myodegeneration, we utilized conditioned media transplant assays and orthotopic models of PDAC-induced cachexia in immune-competent mice with and without macrophage depletion. We observed that macrophage-derived conditioned medium, in combination with tumor cell-conditioned medium, promoted muscle atrophy through STAT3 signaling. Furthermore, macrophage depletion attenuated systemic inflammation and muscle wasting in pancreatic tumor-bearing mice. Targeting macrophage-mediated STAT3 activation or macrophage-derived interleukin-1 alpha or interleukin-6 diminished myofiber atrophy. Taken together, the current study identified the critical association between macrophages and cachexia phenotype in pancreatic cancer.


Assuntos
Caquexia/imunologia , Macrófagos/imunologia , Músculo Esquelético/imunologia , Neoplasias Pancreáticas/imunologia , Fator de Transcrição STAT3/imunologia , Transdução de Sinais/imunologia , Animais , Caquexia/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Células Cultivadas , Meios de Cultivo Condicionados/farmacologia , Citocinas/sangue , Citocinas/imunologia , Citocinas/metabolismo , Humanos , Macrófagos/metabolismo , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/imunologia , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Neoplasias Pancreáticas/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia
15.
Cancers (Basel) ; 12(1)2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31861288

RESUMO

Pancreatic cancer is the third leading cause of cancer-related deaths in the USA. Pancreatic tumors are characterized by enhanced glycolytic metabolism promoted by a hypoxic tumor microenvironment and a resultant acidic milieu. The metabolic reprogramming allows cancer cells to survive hostile microenvironments. Through the analysis of the principal metabolic pathways, we identified the specific metabolites that are altered during pancreatic cancer progression in the spontaneous progression (KPC) mouse model. Genetically engineered mice exhibited metabolic alterations during PanINs formation, even before the tumor development. To account for other cells in the tumor microenvironment and to focus on metabolic adaptations concerning tumorigenic cells only, we compared the metabolic profile of KPC and orthotopic tumors with those obtained from KPC-tumor derived cell lines. We observed significant upregulation of glycolysis and the pentose phosphate pathway metabolites even at the early stages of pathogenesis. Other biosynthetic pathways also demonstrated a few common perturbations. While some of the metabolic changes in tumor cells are not detectable in orthotopic and spontaneous tumors, a significant number of tumor cell-intrinsic metabolic alterations are readily detectable in the animal models. Overall, we identified that metabolic alterations in precancerous lesions are maintained during cancer development and are largely mirrored by cancer cells in culture conditions.

16.
Cancers (Basel) ; 11(9)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500290

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) has a five-year survival rate of <10% due in part to a lack of effective therapies. Pan-histone deacetylase (HDAC) inhibitors have shown preclinical efficacy against PDAC but have failed in the clinic due to toxicity. Selective HDAC inhibitors may reduce toxicity while retaining therapeutic efficacy. However, their use requires identification of the specific HDACs that mediate the therapeutic effects of HDAC inhibitors in PDAC. We determined that the HDAC1/2/3 inhibitor Mocetinostat synergizes with the HDAC4/5/6 inhibitor LMK-235 in a panel of PDAC cell lines. Furthermore, while neither drug alone synergizes with gemcitabine, the combination of Mocetinostat, LMK-235, and gemcitabine showed strong synergy. Using small interfering (si)RNA-mediated knockdown, this synergy was attributed to inhibition of HDACs 1, 2, and 6. Pharmacological inhibition of HDACs 1 and 2 with Romidepsin and HDAC6 with ACY-1215 also potently synergized with gemcitabine in a panel of PDAC cell lines, and this drug combination potentiated the antitumor effects of gemcitabine against PDAC xenografts in vivo. Collectively, our data show that inhibition of multiple HDACs is required for therapeutic effects of HDAC inhibitors and support the development of novel strategies to inhibit HDACs 1, 2, and 6 for PDAC therapy.

17.
Methods Mol Biol ; 1882: 221-228, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30378058

RESUMO

Metabolic reprograming is an established hallmark of cancer cells. Pancreatic cancer cells, by virtue of the underlying oncogenic drivers, demonstrate metabolic reprograming to sustain growth, invasiveness, and therapy resistance. The increased demands of the growing tumor cells alter the metabolic and signaling pathways to meet the growing nutrient requirements. Investigating the metabolic vulnerabilities of tumor cells can help in developing effective therapeutics to target pancreatic cancer. In this chapter, we explain in detail the methods to evaluate the metabolic changes occurring in the tumor. This includes the glucose/glutamine uptake assays and the measurement of reactive oxygen species, extracellular acidification rate, and oxygen consumption rate in the tumor cells. All these physiological assays help in understanding the metabolic nature of the tumor.


Assuntos
Metabolômica/métodos , Pâncreas/metabolismo , Neoplasias Pancreáticas/metabolismo , Trifosfato de Adenosina/metabolismo , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Proliferação de Células , Glucose/análise , Glucose/metabolismo , Glutamina/análise , Glutamina/metabolismo , Glicólise , Humanos , Metabolômica/instrumentação , Mitocôndrias/patologia , Consumo de Oxigênio , Pâncreas/patologia , Neoplasias Pancreáticas/patologia , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo
18.
Methods Mol Biol ; 1882: 321-333, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30378066

RESUMO

Cachexia, a complex metabolic syndrome, is characterized by involuntary weight loss along with muscle wasting and fat depletion leading to poor quality of life of patients. About 80% of pancreatic cancer patients exhibit cachectic phenotype at the time of diagnosis. Here, we present the several molecular and physiological parameters, which we utilize to study the pancreatic cancer-induced cachexia in in vitro models and preclinical mice models of pancreatic cancer. We have described myotube and adipocyte-based in vitro models of muscle and fat wasting, including methods of cell culture, differentiation, and treatment with cancer cell-conditioned medium. Furthermore, we have explained the methods of evaluation of key cachectic markers for muscles. Next, we have detailed the orthotopic implantation mouse models of pancreatic cancer and evaluation of different physiological parameters, including body weight, food intake, body composition analysis, glucose tolerance test, insulin resistance test, grip strength measurement, and rotarod performance test. We have also explained morphological parameters and molecular markers to evaluate the muscle wasting in pancreatic cancer-induced cachexia.


Assuntos
Caquexia/patologia , Técnicas de Cultura de Células/métodos , Neoplasias Pancreáticas/complicações , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Células 3T3-L1 , Absorciometria de Fóton , Adipócitos/fisiologia , Animais , Caquexia/diagnóstico , Caquexia/etiologia , Caquexia/fisiopatologia , Técnicas de Cultura de Células/instrumentação , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Meios de Cultivo Condicionados/farmacologia , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Nus , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Neoplasias Pancreáticas/patologia , Teste de Desempenho do Rota-Rod/instrumentação , Teste de Desempenho do Rota-Rod/métodos , Ensaios Antitumorais Modelo de Xenoenxerto/instrumentação
19.
Methods Mol Biol ; 1742: 95-105, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29330793

RESUMO

Hypoxic conditions in the pancreatic tumor microenvironment lead to the stabilization of hypoxia-inducible factor-1 alpha (HIF-1α), which acts as the master regulator of cancer cell metabolism. HIF-1α-mediated metabolic reprogramming results in large-scale metabolite perturbations. Characterization of the metabolic intermediates and the corresponding metabolic pathways altered by HIF-1α would facilitate the identification of therapeutic targets for hypoxic microenvironments prevalent in pancreatic ductal adenocarcinoma and other solid tumors. Targeted metabolomic approaches are versatile in quantifying multiple metabolite levels in a single platform and, thus, enable the characterization of multiple metabolite alterations regulated by HIF-1α. In this chapter, we describe a detailed metabolomic approach for characterizing the hypoxia-induced metabolomic alterations using pancreatic cancer cell lines cultured in normoxic and hypoxic conditions. We elaborate the methodology of cell culture, hypoxic exposure, metabolite extraction, and relative quantification of polar metabolites from normoxia- and hypoxia-exposed cell extracts, using a liquid chromatography-coupled tandem mass spectrometry approach. Herein, using our metabolomic data, we also present the methods for metabolomic data representation.


Assuntos
Carcinoma Ductal Pancreático/metabolismo , Metabolômica/métodos , Neoplasias Pancreáticas/metabolismo , Técnicas de Cultura de Células , Hipóxia Celular , Linhagem Celular Tumoral , Cromatografia Líquida , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Espectrometria de Massas em Tandem
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