RESUMO
Angiopoietin-like protein 2 (ANGPTL2) is a secreted glycoprotein homologous to angiopoietins. Previous studies suggest that tumor cell-derived ANGPTL2 has tumor-promoting function. Here, we conducted mechanistic analysis comparing ANGPTL2 function in cancer progression in a murine syngeneic model of melanoma and a mouse model of translocation renal cell carcinoma (tRCC). ANGPTL2 deficiency in tumor cells slowed tRCC progression, supporting a tumor-promoting role. However, systemic ablation of ANGPTL2 accelerated tRCC progression, supporting a tumor-suppressing role. The syngeneic model also demonstrated a tumor-suppressing role of ANGPTL2 in host tumor microenvironmental cells. Furthermore, the syngeneic model showed that PDGFRα+ fibroblasts in the tumor microenvironment express abundant ANGPTL2 and contribute to tumor suppression. Moreover, host ANGPTL2 facilitates CD8+ T-cell cross-priming and enhances anti-tumor immune responses. Importantly, ANGPTL2 activates dendritic cells through PIR-B-NOTCH signaling and enhances tumor vaccine efficacy. Our study provides strong evidence that ANGPTL2 can function in either tumor promotion or suppression, depending on what cell type it is expressed in.
Assuntos
Proteínas Semelhantes a Angiopoietina/genética , Proteínas Semelhantes a Angiopoietina/metabolismo , Linfócitos T CD8-Positivos/imunologia , Carcinoma de Células Renais/fisiopatologia , Progressão da Doença , Melanoma/fisiopatologia , Transdução de Sinais , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina/deficiência , Proteínas Semelhantes a Angiopoietina/imunologia , Animais , Vacinas Anticâncer/imunologia , Carcinoma de Células Renais/imunologia , Células Dendríticas/imunologia , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Melanoma/imunologia , Camundongos , Transdução de Sinais/genética , Células Estromais/imunologia , Microambiente Tumoral/genética , Microambiente Tumoral/imunologiaRESUMO
BACKGROUND: Tumor-associated macrophages (TAM), a major component of the tumor microenvironment, play key roles in tumor formation and progression; however, mechanisms underlying TAM-induced tumor progression are complex and not well known. We previously reported that tumor cell-derived angiopoietin-like protein 2 (ANGPTL2) functions as a tumor promoter in some cancer contexts. METHODS: We examined ANGPTL2 expression in paraffin-embedded tumor samples from resected specimens of 221 patients with esophageal cancer. Patients were subdivided into four groups based on immunohistochemistry scores described above: ANGPTL2-low/TAM-low, ANGPTL2-low/TAM-high, ANGPTL2-high/TAM-low, and ANGPTL2-high/TAM-high groups. Gene expression datasets of esophageal cancer cell lines were obtained from the cancer cell line encyclopedia public database. RESULTS: In this study, we demonstrate that TAM infiltration is associated with poor prognosis in patients with esophageal cancer whose tumor cells show relatively higher ANGPTL2 expression levels; however, TAM infiltration did not affect prognosis in patients with ANGPTL2-low-expressing esophageal cancer, suggesting that ANGPTL2 expression in esophageal cancer cells is required for TAM-induced tumor progression. Our analysis of public datasets indicates a potential positive correlation of ANGPTL2 expression levels with that of transforming growth factor (TGF)-ß, a TAM-activating factor, in esophageal cancer cell lines. CONCLUSION: We conclude that ANGPTL2 signaling in tumor cells supports TAM-induced tumor progression and contributes to poor prognosis in patients with esophageal cancer. These findings overall provide novel insight into pro-tumor ANGPTL2 functions and illustrate the essential role of cancer cell/TAM crosstalk in cancer progression.
RESUMO
BACKGROUND: The ability to predict secondary cardiovascular events could improve health of patients undergoing statin treatment. Circulating ANGPTL8 (angiopoietin-like protein 8) levels, which positively correlate with proatherosclerotic lipid profiles, activate the pivotal proatherosclerotic factor ANGPTL3. Here, we assessed potential association between circulating ANGPTL8 levels and risk of secondary cardiovascular events in statin-treated patients. METHODS: We conducted a biomarker study with a case-cohort design, using samples from a 2018 randomized control trial known as randomized evaluation of high-dose (4 mg/day) or low-dose (1 mg/day) lipid-lowering therapy with pitavastatin in coronary artery disease (REAL-CAD [Randomized Evaluation of Aggressive or Moderate Lipid-Lowering Therapy With Pitavastatin in Coronary Artery Disease])." From that study's full analysis set (n=12 413), we selected 2250 patients with stable coronary artery disease (582 with the primary outcome, 1745 randomly chosen, and 77 overlapping subjects). A composite end point including cardiovascular-related death, nonfatal myocardial infarction, nonfatal ischemic stroke, or unstable angina requiring emergent admission was set as a primary end point. Circulating ANGPTL8 levels were measured at baseline and 6 months after randomization. RESULTS: Over a 6-month period, ANGPTL8 level changes significantly decreased in the high-dose pitavastatin group, which showed 19% risk reduction of secondary cardiovascular events compared with the low-dose group in the REAL-CAD [Randomized Evaluation of Aggressive or Moderate Lipid-Lowering Therapy With Pitavastatin in Coronary Artery Disease] study. In the highest quartiles, relative increases in ANGPTL8 levels were significantly associated with increased risk for secondary cardiovascular events, after adjustment for several cardiovascular disease risk factors and pitavastatin treatment (hazard ratio in Q4, 1.67 [95% CI, 1.17-2.39). Subgroup analyses showed relatively strong relationships between relative ANGPTL8 increases and secondary cardiovascular events in the high-dose pitavastatin group (hazard ratio in Q4, 2.07 [95% CI, 1.21-3.55]) and in the low ANGPTL8 group at baseline (166 Assuntos
Doenças Cardiovasculares
, Doença da Artéria Coronariana
, Inibidores de Hidroximetilglutaril-CoA Redutases
, Infarto do Miocárdio
, Hormônios Peptídicos
, Humanos
, Proteína 3 Semelhante a Angiopoietina
, Proteína 8 Semelhante a Angiopoietina
, Doenças Cardiovasculares/sangue
, Doenças Cardiovasculares/induzido quimicamente
, Doenças Cardiovasculares/diagnóstico
, Doenças Cardiovasculares/epidemiologia
, Doença da Artéria Coronariana/sangue
, Doença da Artéria Coronariana/tratamento farmacológico
, Doença da Artéria Coronariana/epidemiologia
, População do Leste Asiático
, Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos
, Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico
, Lipídeos
, Infarto do Miocárdio/tratamento farmacológico
, Resultado do Tratamento
RESUMO
BACKGROUND: Evaluating patients' risk for acute kidney injury (AKI) is crucial for positive outcomes following cardiac surgery. Our aims were first to select candidate risk factors from pre- or intra-operative real-world parameters collected from routine medical care and then evaluate potential associations between those parameters and risk of onset of post-operative cardiac surgery-associated AKI (CSA-AKI). METHOD: We conducted two cohort studies in Japan. The first was a single-center prospective cohort study (n = 145) to assess potential association between 115 clinical parameters collected from routine medical care and CSA-AKI (≥ Stage1) risk in the population of patients undergoing cardiac surgery involving cardiopulmonary bypass (CPB). To select candidate risk factors, we employed random forest analysis and applied survival analyses to evaluate association strength. In a second retrospective cohort study, we targeted patients undergoing cardiac surgery with CPB (n = 619) and evaluated potential positive associations between CSA-AKI incidence and risk factors suggested by the first cohort study. RESULTS: Variable selection analysis revealed that parameters in clinical categories such as circulating inflammatory cells, CPB-related parameters, ventilation, or aging were potential CSA-AKI risk factors. Survival analyses revealed that increased counts of pre-operative circulating monocytes and neutrophils were associated with CSA-AKI incidence. Finally, in the second cohort study, we found that increased pre-operative circulating monocyte counts were associated with increased CSA-AKI incidence. CONCLUSIONS: Circulating monocyte counts in the pre-operative state are associated with increased risk of CSA-AKI development. This finding may be useful in stratifying patients for risk of developing CSA-AKI in routine clinical practice.
Assuntos
Injúria Renal Aguda , Procedimentos Cirúrgicos Cardíacos , Humanos , Estudos de Coortes , Monócitos , Estudos Retrospectivos , Estudos Prospectivos , Ponte Cardiopulmonar/efeitos adversos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/epidemiologia , Injúria Renal Aguda/etiologia , Fatores de Risco , Complicações Pós-Operatórias/epidemiologiaRESUMO
The intestinal epithelium continually self-renews and can rapidly regenerate after damage. Dysregulation of intestinal epithelial homeostasis leads to severe inflammatory bowel disease. Additionally, aberrant signaling by the secreted protein angiopoietin-like protein 2 (ANGPTL2) causes chronic inflammation in a variety of diseases. However, little is known about the physiologic role of ANGPTL2 in normal tissue homeostasis and during wound repair following injury. Here, we assessed ANGPTL2 function in intestinal physiology and disease in vivo Although intestinal development proceeded normally in Angptl2-deficient mice, expression levels of the intestinal stem cell (ISC) marker gene Lgr5 decreased, which was associated with decreased transcriptional activity of ß-catenin in Angptl2-deficient mice. Epithelial regeneration after injury was significantly impaired in Angptl2-deficient relative to wild-type mice. ANGPTL2 was expressed and functioned within the mesenchymal compartment cells known as intestinal subepithelial myofibroblasts (ISEMFs). ANGPTL2 derived from ISEMFs maintained the intestinal stem cell niche by modulating levels of competing signaling between bone morphogenetic protein (BMP) and ß-catenin. These results support the importance of ANGPTL2 in the stem cell niche in regulating stemness and epithelial wound healing in the intestine.
Assuntos
Angiopoietinas/biossíntese , Regulação da Expressão Gênica , Homeostase , Mucosa Intestinal/lesões , Mucosa Intestinal/fisiologia , Regeneração , Nicho de Células-Tronco , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas/deficiência , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Receptores Acoplados a Proteínas G/análise , Cicatrização , beta Catenina/análiseRESUMO
Peritoneal metastasis is a common mode of spread of ovarian cancer. Despite therapeutic advances, some patients have intractable peritoneal metastasis. Therefore, in-depth characterization of the molecular mechanism of peritoneal metastasis is a key imperative. Angiopoietin-like protein 2 (ANGPTL2) is an inflammatory factor which activates NF-κB signaling and plays an important role in the pathogenesis of various inflammatory diseases including cancers, such as lung and breast cancer. In this study, we examined the role of ANGPTL2 in ovarian cancer peritoneal metastasis. We observed no difference of cell proliferation between ANGPTL2-expressing and control cells. In the mouse intraperitoneal xenograft model, formation of peritoneal metastasis by ANGPTL2-expressing cells was significantly decreased compared to control. In the in vitro analysis, the expressions of integrin α5ß1, α6, and ß4, but not those of αvß3, α3, α4, and ß1, were significantly decreased in ANGPTL2-expressing cells compared to control cells. ANGPTL2-expressing cells showed significantly inhibited adherence to laminin compared to control. In addition, we observed upregulation of anoikis (a form of programmed cell death occurring under an anchorage-independent condition) and significant decrease in the expression of Bcl-2 in ANGPTL2-expressing cells as compared to control cells. These results suggest that ANGPTL2 expression in ovarian cancer cells represses peritoneal metastasis by suppressing anoikis resistance.
Assuntos
Proteínas Semelhantes a Angiopoietina/metabolismo , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/metabolismo , Neoplasias Peritoneais/secundário , Proteína 2 Semelhante a Angiopoietina , Animais , Anoikis/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Feminino , Xenoenxertos , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Transdução de SinaisRESUMO
We previously revealed that tumor cell-derived angiopoietin-like protein 2 (ANGPTL2) accelerates the metastatic capacity of tumors in an autocrine/paracrine manner by activating tumor cell motility and invasiveness and the epithelial-mesenchymal transition. However, the effects of ANGPTL2 on cancer cell glycolytic metabolism, which is a hallmark of tumor cells, are unknown. Here we report evidence supporting a role for tumor cell-derived ANGPTL2 in establishing a preference for glycolytic metabolism. We report that a highly metastatic lung cancer cell subline expressing abundant ANGPTL2 showed upregulated expression of the glucose transporter GLUT3 as well as enhanced glycolytic metabolism relative to a less metastatic parental line. Most notably, ANGPTL2 overexpression in the less metastatic line activated glycolytic metabolism by increasing GLUT3 expression. Moreover, ANGPTL2 signaling through integrin α5ß1 increased GLUT3 expression by increasing transforming growth factor-ß (TGF-ß) signaling and expression of the downstream transcription factor zinc finger E-box binding homeobox 1 (ZEB1). Conversely, ANGPTL2 knockdown in the highly metastatic subline decreased TGF-ß1, ZEB1, and GLUT3 expression and antagonized glycolytic metabolism. In primary tumor cells from patients with lung cancer, ANGPTL2 expression levels correlated with GLUT3 expression. Overall, this work suggests that tumor cell-derived ANGPTL2 accelerates activities associated with glycolytic metabolism in lung cancer cells by activating TGF-ß-ZEB1-GLUT3 signaling.
Assuntos
Proteínas Semelhantes a Angiopoietina/genética , Transportador de Glucose Tipo 3/genética , Neoplasias Pulmonares/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Proteína 2 Semelhante a Angiopoietina , Comunicação Autócrina/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Glicólise/genética , Humanos , Integrina alfa5beta1/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Invasividade Neoplásica/genética , Invasividade Neoplásica/patologia , Metástase Neoplásica , Comunicação Parácrina/genética , Fator de Crescimento Transformador beta/genéticaRESUMO
BACKGROUND: Patients undergoing hemodialysis treatment have a poor prognosis, as many develop premature aging. Systemic inflammatory conditions often underlie premature aging phenotypes in uremic patients. We investigated whether angiopoietin-like protein 2 (ANGPTL 2), a factor that accelerates the progression of aging-related and noninfectious inflammatory diseases, was associated with increased mortality risk in hemodialysis patients. METHODS: We conducted a multicenter prospective cohort study of 412 patients receiving maintenance hemodialysis and evaluated the relationship between circulating ANGPTL2 levels and the risk for all-cause mortality. Circulating ANGPTL2 levels were log-transformed to correct for skewed distribution and analyzed as a continuous variable. RESULTS: Of 412 patients, 395 were included for statistical analysis. Time-to-event data analysis showed high circulating ANGPTL2 levels were associated with an increased risk for all-cause mortality after adjustment for age, sex, hemodialysis vintage, nutritional status, metabolic parameters and circulating high-sensitivity C-reactive protein levels {hazard ratio [HR] 2.04 [95% confidence interval (CI) 1.10-3.77]}. High circulating ANGPTL2 levels were also strongly associated with an increased mortality risk, particularly in patients with a relatively benign prognostic profile [HR 3.06 (95% CI 1.86-5.03)]. Furthermore, the relationship between circulating ANGPTL2 levels and mortality risk was particularly strong in patients showing few aging-related phenotypes, such as younger patients [HR 7.99 (95% CI 3.55-18.01)], patients with a short hemodialysis vintage [HR 3.99 (95% CI 2.85-5.58)] and nondiabetic patients [HR 5.15 (95% CI 3.19-8.32)]. CONCLUSION: We conclude that circulating ANGPTL2 levels are positively associated with mortality risk in patients receiving maintenance hemodialysis and that ANGPTL2 could be a unique marker for the progression of premature aging and subsequent mortality risk in uremic patients, except those with significant aging-related phenotypes.
Assuntos
Proteínas Semelhantes a Angiopoietina/sangue , Biomarcadores/sangue , Nefropatias/mortalidade , Diálise Renal/mortalidade , Idoso , Proteína 2 Semelhante a Angiopoietina , Proteína C-Reativa/análise , Progressão da Doença , Feminino , Humanos , Nefropatias/sangue , Nefropatias/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Taxa de SobrevidaRESUMO
Skeletal muscle atrophy, or sarcopenia, is commonly observed in older individuals and in those with chronic disease and is associated with decreased quality of life. There is recent medical and broad concern that sarcopenia is rapidly increasing worldwide as populations age. At present, strength training is the only effective intervention for preventing sarcopenia development, but it is not known how this exercise regimen counteracts this condition. Here, we report that expression of the inflammatory mediator angiopoietin-like protein 2 (ANGPTL2) increases in skeletal muscle of aging mice. Moreover, in addition to exhibiting increased inflammation and accumulation of reactive oxygen species (ROS), denervated atrophic skeletal muscles in a mouse model of denervation-induced muscle atrophy had increased ANGPTL2 expression. Interestingly, mice with a skeletal myocyte-specific Angptl2 knockout had attenuated inflammation and ROS accumulation in denervated skeletal muscle, accompanied by increased satellite cell activity and inhibition of muscular atrophy compared with mice harboring wildtype Angptl2 Moreover, consistent with these phenotypes, wildtype mice undergoing exercise training displayed decreased ANGPTL2 expression in skeletal muscle. In conclusion, ANGPTL2 up-regulation in skeletal myocytes accelerates muscle atrophy, and exercise-induced attenuation of ANGPTL2 expression in those tissues may partially explain how exercise training prevents sarcopenia.
Assuntos
Envelhecimento/metabolismo , Proteínas Semelhantes a Angiopoietina/biossíntese , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Sarcopenia/metabolismo , Regulação para Cima , Envelhecimento/genética , Envelhecimento/patologia , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina/genética , Animais , Feminino , Masculino , Camundongos , Camundongos Knockout , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/patologia , Condicionamento Físico Animal , Sarcopenia/genética , Sarcopenia/patologia , Sarcopenia/prevenção & controleRESUMO
Xp11.2 translocation renal cell carcinoma (Xp11 tRCC) is a rare sporadic pediatric kidney cancer caused by constitutively active TFE3 fusion proteins. Tumors in patients with Xp11 tRCC tend to recur and undergo frequent metastasis, in part due to lack of methods available to detect early-stage disease. Here we generated transgenic (Tg) mice overexpressing the human PRCC-TFE3 fusion gene in renal tubular epithelial cells, as an Xp11 tRCC mouse model. At 20 weeks of age, mice showed no histological abnormalities in kidney but by 40 weeks showed Xp11 tRCC development and related morphological and histological changes. MicroRNA (miR)-204-5p levels in urinary exosomes of 40-week-old Tg mice showing tRCC were significantly elevated compared with levels in control mice. MicroRNA-204-5p expression also significantly increased in primary renal cell carcinoma cell lines established both from Tg mouse tumors and from tumor tissue from 2 Xp11 tRCC patients. All of these lines secreted miR-204-5p-containing exosomes. Notably, we also observed increased miR-204-5p levels in urinary exosomes in 20-week-old renal PRCC-TFE3 Tg mice prior to tRCC development, and those levels were equivalent to those in 40-week-old Tg mice, suggesting that miR-204-5p increases follow expression of constitutively active TFE3 fusion proteins in renal tubular epithelial cells prior to overt tRCC development. Finally, we confirmed that miR-204-5p expression significantly increases in noncancerous human kidney cells after overexpression of a PRCC-TFE3 fusion gene. These findings suggest that miR-204-5p in urinary exosomes could be a useful biomarker for early diagnosis of patients with Xp11 tRCC.
Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Cromossomos Humanos X/genética , Neoplasias Renais/genética , MicroRNAs/genética , Translocação Genética , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Biomarcadores Tumorais/urina , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/urina , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Exossomos/genética , Humanos , Rim/anormalidades , Rim/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Renais/urina , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , MicroRNAs/urina , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismoRESUMO
BACKGROUND: The rapid increase in the number of heart failure (HF) patients in parallel with the increase in the number of older people is receiving attention worldwide. HF not only increases mortality but decreases quality of life, creating medical and social problems. Thus, it is necessary to define molecular mechanisms underlying HF development and progression. HMGB2 is a member of the high-mobility group superfamily characterized as nuclear proteins that bind DNA to stabilize nucleosomes and promote transcription. A recent in vitro study revealed that HMGB2 loss in cardiomyocytes causes hypertrophy and increases HF-associated gene expression. However, it's in vivo function in the heart has not been assessed. MethodsâandâResults: Western blotting analysis revealed increased HMGB2 expression in heart tissues undergoing pressure overload by transverse aorta constriction (TAC) in mice. Hmgb2 homozygous knockout (Hmgb2-/-) mice showed cardiac dysfunction due to AKT inactivation and decreased sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA)2a activity. Compared to wild-type mice, Hmgb2-/- mice had worsened cardiac dysfunction after TAC surgery, predisposing mice to HF development and progression. CONCLUSIONS: This study demonstrates that upregulation of cardiac HMGB2 is an adaptive response to cardiac stress, and that loss of this response could accelerate cardiac dysfunction, suggesting that HMGB2 plays a cardioprotective role.
Assuntos
Proteína HMGB2/análise , Insuficiência Cardíaca/etiologia , Animais , Western Blotting , Cardiotônicos/análise , Cardiotônicos/farmacologia , Constrição Patológica/complicações , Proteína HMGB2/genética , Proteína HMGB2/farmacologia , Insuficiência Cardíaca/prevenção & controle , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas c-akt/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismoRESUMO
BACKGROUND: Recently, it was reported that angiopoietin-like protein 2 (ANGPTL2) secreted from a pathologically stressed heart accelerates cardiac dysfunction in an autocrine/paracrine manner, and that suppression of ANGPTL2 production in the heart restored cardiac function and myocardial energy metabolism, thereby blocking heart failure (HF) development. Interestingly, circulating ANGPTL2 concentrations reportedly increase in HF patients, suggesting a possible endocrine effect on cardiac dysfunction. However, it remains unclear why circulating ANGPTL2 increases in those subjects and whether circulating ANGPTL2 alters cardiac function in an endocrine manner.MethodsâandâResults:It was found that circulating ANGPTL2 levels are positively correlated with left atrial diameter and pulmonary capillary wedge pressure, and are inversely proportional to the percent of ejection fraction in patients with dilated cardiomyopathy. Furthermore, in mice, circulating ANGPTL2 concentrations increased as HF developed following transverse aorta constriction (TAC), and were inversely correlated with the percent of fractional shortening. Interestingly, although circulating ANGPTL2 concentrations significantly increased in transgenic mice overexpressing keratinocyte-derived ANGPTL2, no pathological cardiac remodeling was seen. Furthermore, it was observed that there was no difference in HF development between transgenic mice and controls following TAC surgery. CONCLUSIONS: Circulating ANGPTL2 levels increase in subjects experiencing cardiac dysfunction. However, circulating ANGPTL2 does not promote cardiac dysfunction in an endocrine manner, and increased levels of circulating ANGPTL2 seen during HF are a secondary effect of increased ANGPTL2 secretion from stressed hearts in HF pathologies.
Assuntos
Proteínas Semelhantes a Angiopoietina/sangue , Cardiopatias/sangue , Insuficiência Cardíaca/sangue , Adulto , Idoso , Proteína 2 Semelhante a Angiopoietina , Animais , Cardiomiopatia Dilatada/sangue , Feminino , Insuficiência Cardíaca/prevenção & controle , Humanos , Queratinócitos/química , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Miócitos Cardíacos/metabolismoRESUMO
Macrophages play crucial roles in combatting infectious disease by promoting inflammation and phagocytosis. Angiopoietin-like protein 2 (ANGPTL2) is a secreted factor that induces tissue inflammation by attracting and activating macrophages to produce inflammatory cytokines in chronic inflammation-associated diseases such as obesity-associated metabolic syndrome, atherosclerosis, and rheumatoid arthritis. Here, we asked whether and how ANGPTL2 activates macrophages in the innate immune response. ANGPTL2 was predominantly expressed in proinflammatory mouse bone marrow-derived differentiated macrophages (GM-BMMs) following GM-CSF treatment relative to anti-inflammatory cells (M-BMMs) established by M-CSF treatment. Expression of the proinflammatory markers IL-1ß, IL-12p35, and IL-12p40 significantly decreased in GM-BMMs from Angptl2-deficient compared with wild-type (WT) mice, suggestive of attenuated proinflammatory activity. We also report that ANGPTL2 inflammatory signaling is transduced through integrin α5ß1 rather than through paired immunoglobulin-like receptor B. Interestingly, Angptl2-deficient mice were more susceptible to infection with Salmonella enterica serovar Typhimurium than were WT mice. Moreover, nitric oxide (NO) production by Angptl2-deficient GM-BMMs was significantly lower than in WT GM-BMMs. Collectively, our findings suggest that macrophage-derived ANGPTL2 promotes an innate immune response in those cells by enhancing proinflammatory activity and NO production required to fight infection.
Assuntos
Angiopoietinas/imunologia , Predisposição Genética para Doença , Imunidade Inata , Macrófagos/imunologia , Óxido Nítrico/imunologia , Infecções por Salmonella/imunologia , Salmonella typhimurium/imunologia , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas/genética , Animais , Feminino , Camundongos , Camundongos Knockout , Óxido Nítrico/genética , Infecções por Salmonella/genéticaRESUMO
In parallel with the increase in the number of elderly people worldwide, the number of patients with heart disease is also rapidly increasing. Of the heart diseases, cardiovascular disease (CVD) and heart failure (HF) are strongly associated with adverse health outcomes that decrease productivity in later years. Recently, ANGPTL2, a secreted glycoprotein and member of the angiopoietin-like protein family, has received attention as a causal player in the development of CVD and HF. Prolonged ANGPTL2 autocrine/paracrine signaling in vascular tissue leads to chronic inflammation and pathologic tissue remodeling, accelerating CVD development. Excess ANGPTL2 autocrine/paracrine signaling induced in the pathologically stressed heart accelerates cardiac dysfunction by decreasing myocardial energy metabolism. Conversely, ANGPTL2 inactivation in vascular tissue and the heart delays development or progression of CVD and HF, respectively. Moreover, there is increased evidence for an association between elevated circulating ANGPTL2 levels and CVD and HF. Interestingly, ANGPTL2 expression is also associated with cellular senescence, which may promote premature aging and development of aging-associated diseases, including CVD and HF. Overall, ANGPTL2 autocrine/paracrine signaling is a new factor in accelerating heart disease development in the aging. Here, we focus on current topics relevant to ANGPTL2 function in heart disease.
Assuntos
Proteínas Semelhantes a Angiopoietina/fisiologia , Cardiopatias/etiologia , Idoso , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina/sangue , Comunicação Autócrina , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , Senescência Celular , Cardiopatias/patologia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/patologia , Humanos , Inflamação , Comunicação ParácrinaRESUMO
Angiopoietin-like protein 2 (ANGPTL2) is a chronic inflammatory mediator that, when deregulated, is associated with various pathologies. However, little is known about its activity in lung. To assess a possible lung function, we generated a rabbit monoclonal antibody that specifically recognizes mouse ANGPTL2 and then evaluated protein expression in mouse lung tissue. We observed abundant ANGPTL2 expression in both alveolar epithelial type I and type II cells and in resident alveolar macrophages under normal conditions. To assess ANGPTL2 function, we compared lung phenotypes in Angptl2 knockout (KO) and wild-type mice but observed no overt changes. We then generated a bleomycin-induced interstitial pneumonia model using wild-type and Angptl2 KO mice. Bleomycin-treated wild-type mice showed specifically upregulated ANGPTL2 expression in areas of severe fibrosing interstitial pneumonia, while Angptl2 KO mice developed more severe lung fibrosis than did comparably treated wild-type mice. Lung fibrosis seen following bone marrow transplant was comparable in wild-type or Angptl2 KO mice treated with bleomycin, suggesting that Angptl2 loss in myeloid cells does not underlie fibrotic phenotypes. We conclude that Angptl2 deficiency in lung epithelial cells and resident alveolar macrophages causes severe lung fibrosis seen following bleomycin treatment, suggesting that ANGPTL2 derived from these cell types plays a protective role against fibrosis in lung.
Assuntos
Angiopoietinas/genética , Doenças Pulmonares Intersticiais/genética , Fibrose Pulmonar/genética , Células 3T3-L1 , Células Epiteliais Alveolares/metabolismo , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas/metabolismo , Animais , Bleomicina , Pulmão/patologia , Doenças Pulmonares Intersticiais/induzido quimicamente , Doenças Pulmonares Intersticiais/patologia , Macrófagos Alveolares/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Células Mieloides/metabolismo , Fibrose Pulmonar/induzido quimicamente , Fibrose Pulmonar/patologia , Trombospondina 1/genética , Trombospondina 1/metabolismoRESUMO
Renal fibrosis is a common pathological consequence of chronic kidney disease (CKD) with tissue fibrosis closely associated with chronic inflammation in numerous pathologies. However, molecular mechanisms underlying that association, particularly in the kidney, remain unclear. Here, we determine whether there is a molecular link between chronic inflammation and tissue fibrosis in CKD progression. Histological analysis of human kidneys indicated abundant expression of angiopoietin-like protein 2 (ANGPTL2) in renal tubule epithelial cells during progression of renal fibrosis. Numerous ANGPTL2-positive renal tubule epithelial cells colocalized with cells positive for transforming growth factor (TGF)-ß1, a critical mediator of tissue fibrosis. Analysis of M1 collecting duct cells in culture showed that TGF-ß1 increases ANGPTL2 expression by attenuating its repression through microRNA-221. Conversely, ANGPTL2 increased TGF-ß1 expression through α5ß1 integrin-mediated activation of extracellular signal-regulated kinase. Furthermore, ANGPTL2 deficiency in a mouse unilateral ureteral obstruction model significantly reduced renal fibrosis by decreasing TGF-ß1 signal amplification in kidney. Thus, ANGPTL2 and TGF-ß1 positively regulate each other as renal fibrosis progresses. Our study provides insight into molecular mechanisms underlying chronic inflammation and tissue fibrosis and identifies potential therapeutic targets for CKD treatment.
Assuntos
Angiopoietinas/metabolismo , MicroRNAs/metabolismo , Insuficiência Renal Crônica/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Idoso , Idoso de 80 Anos ou mais , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Animais , Modelos Animais de Doenças , Feminino , Fibrose , Humanos , Integrina alfa5beta1/metabolismo , Rim/patologia , Túbulos Renais/imunologia , Túbulos Renais/metabolismo , Macrófagos/fisiologia , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Insuficiência Renal Crônica/patologiaRESUMO
Obesity is a life-threatening factor and is often associated with dysregulation of gene expression. Here, we show that the CNOT3 subunit of the CCR4-NOT deadenylase complex is critical to metabolic regulation. Cnot3(+/-) mice are lean with hepatic and adipose tissues containing reduced levels of lipids, and show increased metabolic rates and enhanced glucose tolerance. Cnot3(+/-) mice remain lean and sensitive to insulin even on a high-fat diet. Furthermore, introduction of Cnot3 haplodeficiency in ob/ob mice ameliorated the obese phenotype. Hepatic expression of most mRNAs is not altered in Cnot3(+/-) vis-à-vis wild-type mice. However, the levels of specific mRNAs, such as those coding for energy metabolism-related PDK4 and IGFBP1, are increased in Cnot3(+/-) hepatocytes, having poly(A) tails that are longer than those seen in control cells. We provide evidence that CNOT3 is involved in recruitment of the CCR4-NOT deadenylase to the 3' end of specific mRNAs. Finally, as CNOT3 levels in the liver and white adipose tissues decrease upon fasting, we propose that CNOT3 responds to feeding conditions to regulate deadenylation-specific mRNAs and energy metabolism.
Assuntos
Metabolismo Energético , Obesidade/genética , RNA Mensageiro/biossíntese , Fatores de Transcrição/metabolismo , Tecido Adiposo/metabolismo , Animais , Dieta , Insulina/metabolismo , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Fígado/metabolismo , Camundongos , Camundongos Obesos/genética , Camundongos Obesos/metabolismo , Camundongos Transgênicos , Dados de Sequência Molecular , Obesidade/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , Proteínas Serina-Treonina Quinases/genética , Piruvato Desidrogenase Quinase de Transferência de Acetil , RNA Mensageiro/genética , Fatores de Transcrição/genéticaRESUMO
OBJECTIVE: Cardiovascular disease (CVD), the most common morbidity resulting from atherosclerosis, remains a frequent cause of death. Efforts to develop effective therapeutic strategies have focused on vascular inflammation as a critical pathology driving atherosclerosis progression. Nonetheless, molecular mechanisms underlying this activity remain unclear. Here, we ask whether angiopoietin-like protein 2 (Angptl2), a proinflammatory protein, contributes to vascular inflammation that promotes atherosclerosis progression. APPROACH AND RESULTS: Histological analysis revealed abundant Angptl2 expression in endothelial cells and macrophages infiltrating atheromatous plaques in patients with cardiovascular disease. Angptl2 knockout in apolipoprotein E-deficient mice (ApoE(-/-)/Angptl2(-/-)) attenuated atherosclerosis progression by decreasing the number of macrophages infiltrating atheromatous plaques, reducing vascular inflammation. Bone marrow transplantation experiments showed that Angptl2 deficiency in endothelial cells attenuated atherosclerosis development. Conversely, ApoE(-/-) mice crossed with transgenic mice expressing Angptl2 driven by the Tie2 promoter (ApoE(-/-)/Tie2-Angptl2 Tg), which drives Angptl2 expression in endothelial cells but not monocytes/macrophages, showed accelerated plaque formation and vascular inflammation because of increased numbers of infiltrated macrophages in atheromatous plaques. Tie2-Angptl2 Tg mice alone did not develop plaques but exhibited endothelium-dependent vasodilatory dysfunction, likely because of decreased production of endothelial cell-derived nitric oxide. Conversely, Angptl2(-/-) mice exhibited less severe endothelial dysfunction than did wild-type mice when fed a high-fat diet. In vitro, Angptl2 activated proinflammatory nuclear factor-κB signaling in endothelial cells and increased monocyte/macrophage chemotaxis. CONCLUSIONS: Endothelial cell-derived Angptl2 accelerates vascular inflammation by activating proinflammatory signaling in endothelial cells and increasing macrophage infiltration, leading to endothelial dysfunction and atherosclerosis progression.
Assuntos
Angiopoietinas/metabolismo , Aterosclerose/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Mediadores da Inflamação/metabolismo , Vasculite/metabolismo , Idoso de 80 Anos ou mais , Proteína 2 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Angiopoietinas/deficiência , Angiopoietinas/genética , Animais , Apolipoproteínas E/deficiência , Apolipoproteínas E/genética , Aterosclerose/genética , Aterosclerose/imunologia , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Transplante de Medula Óssea , Células Cultivadas , Quimiotaxia de Leucócito , Dieta Hiperlipídica , Modelos Animais de Doenças , Progressão da Doença , Dislipidemias/metabolismo , Dislipidemias/fisiopatologia , Células Endoteliais/imunologia , Células Endoteliais/patologia , Endotélio Vascular/imunologia , Endotélio Vascular/patologia , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Integrina alfa5beta1/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/imunologia , Monócitos/metabolismo , NF-kappa B/metabolismo , Fatores de Transcrição NFATC/metabolismo , Óxido Nítrico/metabolismo , Obesidade/metabolismo , Obesidade/fisiopatologia , Placa Aterosclerótica , Transdução de Sinais , Fatores de Tempo , Vasculite/genética , Vasculite/imunologia , Vasculite/patologia , Vasculite/prevenção & controle , VasodilataçãoRESUMO
Angiopoietin-like protein 2 (ANGPTL2) plays an important role in inflammatory carcinogenesis and tumor metastasis by activating tumor angiogenesis and tumor cell chemotaxis and invasiveness. However, it is unclear whether ANGPTL2 expression has an effect on tumor cell survival. Here, we explored that possibility by determining whether ANGPTL2 expression altered survival of human colorectal cancer cell lines treated with antineoplastic drugs. To do so, we generated SW480 cells expressing ANGPTL2 (SW480/ANGPTL2) and control (SW480/Ctrl) cells. Apoptosis induced by antineoplastic drug treatment was significantly decreased in SW480/ANGPTL2 compared to control cells. Expression of anti-apoptotic BCL-2 family genes was upregulated in SW480/ANGPTL2 compared to SW480/Ctrl cells. To assess signaling downstream of ANGPTL2 underlying this effect, we carried out RNA sequencing analysis of SW480/ANGPTL2 and SW480/Ctrl cells. That analysis, combined with in vitro experiments, indicated that Syk-PI3K signaling induced expression of BCL-2 family genes in SW480/ANGPTL2 cells. Furthermore, ANGPTL2 increased its own expression in a feedback loop by activating the spleen tyrosine kinase-nuclear factor of activated T cells (Syk-NFAT) pathway. Finally, we observed a correlation between higher ANGPTL2 expression in primary unresectable tumors from colorectal cancer patients who underwent chemotherapy with a lower objective response rate. These findings suggest that attenuating ANGPTL2 signaling in tumor cells may block tumor cell resistance to antineoplastic therapies.