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1.
Proc Natl Acad Sci U S A ; 119(9)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35210363

RESUMO

Cancer-associated cachexia (CAC) is a hypermetabolic syndrome characterized by unintended weight loss due to the atrophy of adipose tissue and skeletal muscle. A phenotypic switch from white to beige adipocytes, a phenomenon called browning, accelerates CAC by increasing the dissipation of energy as heat. Addressing the mechanisms of white adipose tissue (WAT) browning in CAC, we now show that cachexigenic tumors activate type 2 immunity in cachectic WAT, generating a neuroprotective environment that increases peripheral sympathetic activity. Increased sympathetic activation, in turn, results in increased neuronal catecholamine synthesis and secretion, ß-adrenergic activation of adipocytes, and induction of WAT browning. Two genetic mouse models validated this progression of events. 1) Interleukin-4 receptor deficiency impeded the alternative activation of macrophages, reduced sympathetic activity, and restrained WAT browning, and 2) reduced catecholamine synthesis in peripheral dopamine ß-hydroxylase (DBH)-deficient mice prevented cancer-induced WAT browning and adipose atrophy. Targeting the intraadipose macrophage-sympathetic neuron cross-talk represents a promising therapeutic approach to ameliorate cachexia in cancer patients.


Assuntos
Tecido Adiposo Marrom/patologia , Caquexia/patologia , Comunicação Celular , Neoplasias/complicações , Neurônios/patologia , Sistema Nervoso Simpático/patologia , Animais , Caquexia/etiologia , Caquexia/metabolismo , Expressão Gênica , Xenoenxertos , Humanos , Camundongos , Neoplasias/metabolismo , Receptores Adrenérgicos beta/metabolismo , Termogênese
2.
Nephrol Dial Transplant ; 36(9): 1577-1584, 2021 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32542315

RESUMO

Chronic kidney disease (CKD) is a progressive multisystem condition with yet undefined mechanistic drivers and multiple implicated soluble factors. If identified, these factors could be targeted for therapeutic intervention for a disease that currently lacks specific treatment. There is increasing preclinical evidence that the heparin/endothelial glycocalyx-binding molecule midkine (MK) has a pathological role in multiple CKD-related, organ-specific disease processes, including CKD progression, hypertension, vascular and cardiac disease, bone disease and CKD-related cancers. Concurrent with this are studies documenting increases in circulating and urine MK proportional to glomerular filtration rate (GFR) loss in CKD patients and evidence that administering soluble MK reverses the protective effects of MK deficiency in experimental kidney disease. This review summarizes the growing body of evidence supporting MK's potential role in driving CKD-related multisystem disease, including MK's relationship with the endothelial glycocalyx, the deranged MK levels and glycocalyx profile in CKD patients and a proposed model of MK organ interplay in CKD disease processes and highlights the importance of ongoing research into MK's potential as a therapeutic target.


Assuntos
Insuficiência de Múltiplos Órgãos , Insuficiência Renal Crônica , Taxa de Filtração Glomerular , Humanos , Estudos Longitudinais , Midkina , Insuficiência Renal Crônica/etiologia
3.
Sci Rep ; 10(1): 14499, 2020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32879333

RESUMO

Midkine (MDK), a heparin-binding growth factor cytokine, is involved in the pathogenesis of kidney diseases by augmenting leukocyte trafficking and activation. Animal models and small case control studies have implicated MDK as a pathological biomarker in chronic kidney diseases (CKD), however this is yet to be confirmed in prospective human studies. In a prospective study of 499 elderly, predominantly Caucasian women aged over 70 years the association between serum MDK collected in 1998, and renal function change and the risk of CKD-related hospitalisations and deaths at 5 and 14.5 years, respectively, was examined. Baseline serum MDK was not associated with 5-year change in estimated glomerular filtration rate using the CKD Epidemiology Collaboration creatinine and cystatin C equation (Standardised ß = - 0.09, 95% confidence interval - 3.76-0.48, p = 0.129), 5-year rapid decline in renal function (odds ratio = 0.97, 95% confidence interval 0.46-2.02, p = 0.927) or the risk of 14.5-year CKD-related hospitalisations and deaths (hazard ratio = 1.27, 95% confidence interval .66-2.46, p = 0.470) before or after adjusting for major risk factors. In conclusion, in this cohort of elderly women with normal or mildly impaired renal function, serum MDK was not associated with renal function change or future CKD-related hospitalisations and deaths, suggesting that MDK may not be an early biomarker for progression of CKD.


Assuntos
Taxa de Filtração Glomerular , Falência Renal Crônica/terapia , Midkina/sangue , Idoso , Envelhecimento , Biomarcadores/metabolismo , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco , Austrália Ocidental
4.
J Pathol ; 251(1): 63-73, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32129471

RESUMO

The immune microenvironment in inflammatory breast cancer (IBC) is poorly characterised, and molecular and cellular pathways that control accumulation of various immune cells in IBC tissues remain largely unknown. Here, we discovered a novel pathway linking the expression of the tetraspanin protein CD151 in tumour cells with increased accumulation of macrophages in cancerous tissues. It is notable that elevated expression of CD151 and a higher number of tumour-infiltrating macrophages correlated with better patient responses to chemotherapy. Accordingly, CD151-expressing IBC xenografts were characterised by the increased infiltration of macrophages. In vitro migration experiments demonstrated that CD151 stimulates the chemoattractive potential of IBC cells for monocytes via mechanisms involving midkine (a heparin-binding growth factor), integrin α6ß1, and production of extracellular vesicles (EVs). Profiling of chemokines secreted by IBC cells demonstrated that CD151 increases production of midkine. Purified midkine specifically stimulated migration of monocytes, but not other immune cells. Further experiments demonstrated that the chemoattractive potential of IBC-derived EVs is blocked by anti-midkine antibodies. These results demonstrate for the first time that changes in the expression of a tetraspanin protein by tumour cells can affect the formation of the immune microenvironment by modulating recruitment of effector cells to cancerous tissues. Therefore, a CD151-midkine pathway can be considered as a novel target for controlled changes of the immune landscape in IBC. © 2020 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Neoplasias Inflamatórias Mamárias/patologia , Macrófagos/patologia , Tetraspanina 24/metabolismo , Microambiente Tumoral/fisiologia , Linhagem Celular Tumoral , Quimiocinas/metabolismo , Humanos , Neoplasias Inflamatórias Mamárias/metabolismo , Macrófagos/metabolismo , Midkina/metabolismo , Tetraspanina 24/imunologia
5.
Int J Surg ; 52: 7-10, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29427751

RESUMO

INTRODUCTION: Intra-operative assessment of total knee arthroplasty (TKA) components is performed with manufacturer specific jigs. Pre-operative templating, patient specific knee cutting blocks and computer-assisted surgeries have also been used to improve alignment and sizing; although the literature shows marginal improvement in functional scores. We propose pre-operative shoe size as a simple measurement tool for estimating the component sizes required for TKA. We investigate the relationship between TKA implant sizes, height, body weight and shoe size. METHODS: Retrospective single centre cohort study of all patients undergoing primary knee arthroplasty over a four-month period (August-November 2015) was conducted. Standard data items recorded during routine admission. The spearman's rank correlation was used to assess the relationship between variables. RESULTS: One hundred and six patients were included in the final analysis. The mean age of the study group was 67.3 ±â€¯10.1 years (Range 44-90.) There were 42 male patients and 64 female patients. Statistically significant correlations were observed between: Shoe size and femoral component (rho = 0.589, p < 0.05); shoe size and tibial component (rho = 0.718, p < 0.05); shoe size and height (rho = 0.692, p < 0.05); height and femoral component (rho = 0.626, p < 0.05); height and tibial component (rho = 0.674, p < 0.05). CONCLUSION: We have demonstrated positive correlation between shoe and TKR component sizes. This relationship allows surgeons to estimate prosthesis size in the pre-operative setting.


Assuntos
Artroplastia do Joelho/métodos , Articulação do Joelho/cirurgia , Prótese do Joelho/estatística & dados numéricos , Adulto , Idoso , Idoso de 80 Anos ou mais , Antropometria/métodos , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sapatos/estatística & dados numéricos , Tíbia/cirurgia
6.
Semin Cell Dev Biol ; 54: 68-81, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26529279

RESUMO

Although muscle wasting is the obvious manifestation of cancer cachexia that impacts on patient quality of life, the loss of lipid reserves and metabolic imbalance in adipose tissue also contribute to the devastating impact of cachexia. Depletion of fat depots in cancer patients is more pronounced than loss of muscle and often precedes, or even occurs in the absence of, reduced lean body mass. Rapid mobilisation of triglycerides stored within adipocytes to supply the body with fatty acids in periods of high-energy demand is normally mediated through a well-defined process of lipolysis involving the lipases ATGL, HSL and MGL. Studies into how these lipases contribute to fat loss in cancer cachexia have revealed the prominent role for ATGL in initiating lipolysis during adipose tissue atrophy, together with links between tumour-derived factors and the signalling pathways that control lipid flux within fat cells. The recent findings of increased thermogenesis in brown fat during cancer cachexia indicate that metabolically active adipose tissue contributes to the imbalance in energy homeostasis involved in catabolic wasting. Such energetically futile use of fatty acids liberated from adipose tissue to generate heat represents a maladaptive response in conjunction with anorexia experienced by cancer patients. As IL-6 release by tumours provokes lipolysis and activates the thermogenic programme in brown fat, this review explores the overlap in dysregulated metabolic processes due to inflammatory mediators in cancer cachexia and other disease states characterised by elevated cytokines such as obesity and diabetes.


Assuntos
Tecido Adiposo/metabolismo , Caquexia/etiologia , Caquexia/metabolismo , Lipólise , Neoplasias/complicações , Termogênese , Animais , Caquexia/fisiopatologia , Metabolismo Energético , Humanos , Neoplasias/fisiopatologia
7.
Cell Metab ; 20(3): 433-47, 2014 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-25043816

RESUMO

Cancer-associated cachexia (CAC) is a wasting syndrome characterized by systemic inflammation, body weight loss, atrophy of white adipose tissue (WAT) and skeletal muscle. Limited therapeutic options are available and the underlying mechanisms are poorly defined. Here we show that a phenotypic switch from WAT to brown fat, a phenomenon termed WAT browning, takes place in the initial stages of CAC, before skeletal muscle atrophy. WAT browning is associated with increased expression of uncoupling protein 1 (UCP1), which uncouples mitochondrial respiration toward thermogenesis instead of ATP synthesis, leading to increased lipid mobilization and energy expenditure in cachectic mice. Chronic inflammation and the cytokine interleukin-6 increase UCP1 expression in WAT, and treatments that reduce inflammation or ß-adrenergic blockade reduce WAT browning and ameliorate the severity of cachexia. Importantly, UCP1 staining is observed in WAT from CAC patients. Thus, inhibition of WAT browning represents a promising approach to ameliorate cachexia in cancer patients.


Assuntos
Tecido Adiposo Marrom/patologia , Tecido Adiposo Branco/patologia , Caquexia/complicações , Neoplasias/complicações , Tecido Adiposo Marrom/imunologia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/imunologia , Tecido Adiposo Branco/metabolismo , Animais , Anti-Inflamatórios/uso terapêutico , Caquexia/imunologia , Caquexia/metabolismo , Caquexia/patologia , Metabolismo Energético , Humanos , Inflamação/complicações , Inflamação/imunologia , Inflamação/metabolismo , Inflamação/patologia , Canais Iônicos/análise , Camundongos , Proteínas Mitocondriais/análise , Neoplasias/imunologia , Neoplasias/metabolismo , Neoplasias/patologia , Proteína Desacopladora 1
8.
PLoS One ; 9(3): e92966, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24667661

RESUMO

Involuntary weight loss in patients with cancer is the hallmark of cancer cachexia. The etiology of cachexia is multifactorial involving loss of skeletal muscle and adipose tissue associated with high systemic levels of acute phase proteins and inflammatory cytokines. While muscle wasting overtly impacts on cancer patient quality of life, loss of lipid depots represents a sustained energy imbalance. In this study fat depletion was examined in Colon-26 model of cancer cachexia, which is a widely used rodent model of this syndrome. We investigated diurnal expression of circadian rhythm regulators as well as key mediators of energy metabolism and cytokine signaling. Mice bearing the C26 tumour exhibited reduced adipose mass, elevated adipose tissue lipolysis and a 5-fold increase in plasma levels of free fatty acids. These changes were associated with activated IL-6 signaling in WAT through a 3-fold increase in phosphorylated STAT3 and high SOCS3 gene expression levels. In addition perturbations in circadian regulation of lipid metabolism were also observed. Lipid catabolism did not appear to be influenced by the classical PKA pathway activating the lipase HSL. ATGL protein levels were elevated 2-fold in cachectic mice while 4-fold increase phosphorylated ACC and a 2-fold decrease in phosphorylated 4EBP1 was observed indicating that lipid metabolism is modulated by the ATGL & AMPK/mTOR pathways. This study provides evidence for activation of cytokine signaling and concomitant alterations in circadian rhythm and regulators of lipid metabolism in WAT of cachectic animals.


Assuntos
Tecido Adiposo Branco/patologia , Caquexia/patologia , Caquexia/fisiopatologia , Ritmo Circadiano , Neoplasias do Colo/patologia , Transdução de Sinais , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Caquexia/metabolismo , Proteínas de Transporte/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Fatores de Iniciação em Eucariotos , Inflamação/patologia , Interleucina-6/metabolismo , Lipogênese , Lipólise , Camundongos , Fosfoproteínas/metabolismo , Serina-Treonina Quinases TOR/metabolismo
9.
Pharm Res ; 30(9): 2270-8, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23604979

RESUMO

PURPOSE: In many cancer patients, the malignancy causes reduced hepatic drug clearance leading to potentially serious complications from the use of anticancer drugs. The mechanisms underlying this phenomenon are poorly understood. We aimed to identify tumor-associated inflammatory pathways that alter drug response and enhance chemotherapy-associated toxicity. METHODS: We studied inflammatory pathways involved in extra-hepatic tumor mediated repression of CYP3A, a major hepatic drug metabolizing cytochrome P450 subfamily, using a murine Engelbreth-Holm-Swarm sarcoma model. Studies in IL-6 knockout mice determined the source of elevated IL-6 in tumor-bearing animals and monoclonal antibodies against IL-6 were used to intervene in this inflammatory pathway. RESULTS: Our studies confirm elevated plasma IL-6 levels and reveal activation of Jak/Stat and Mapk signalling pathways and acute phase proteins in livers of tumor-bearing mice. Circulating IL-6 was predominantly produced by the tumor xenograft, rather than being host derived. Anti IL-6 antibody intervention partially reversed tumor-mediated inflammation and Cyp3a gene repression. CONCLUSIONS: IL-6 is an important player in cancer-related repression of CYP3A-mediated drug metabolism and activation of the acute phase response. Targeting IL-6 in cancer patients may prove an effective approach to alleviating cancer-related phenomena, such as adverse drug-related outcomes commonly associated with cancer chemotherapy.


Assuntos
Antineoplásicos/metabolismo , Citocromo P-450 CYP3A/metabolismo , Interleucina-6/imunologia , Fígado/metabolismo , Sarcoma Experimental/imunologia , Animais , Citocromo P-450 CYP3A/imunologia , Interleucina-6/genética , Fígado/efeitos dos fármacos , Fígado/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Sarcoma Experimental/tratamento farmacológico , Sarcoma Experimental/metabolismo
10.
Trends Endocrinol Metab ; 24(4): 174-83, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23201432

RESUMO

Cachexia has a devastating impact on survival and quality of life for many cancer patients. A better understanding of the underlying mechanisms leading to the complex metabolic defects of cachexia, coupled with effective treatment options, will improve management of wasting in cancer patients. The growing appreciation that cancer cachexia results from the spillover effects of cytokine production by tumors on the integrated regulation of energy balance in different organs identifies potential therapeutic options. However, targeting such tumorkines requires a comprehensive understanding of their normal as well as pathophysiological functions, especially the crosstalk between inflammatory signaling and metabolic dysregulation. Recent advances in characterizing the surprising parallels between obesity and cancer cachexia provide new insights into these apparently divergent syndromes.


Assuntos
Caquexia/imunologia , Caquexia/metabolismo , Neoplasias/complicações , Animais , Caquexia/etiologia , Metabolismo Energético/fisiologia , Humanos , Inflamação/imunologia , Inflamação/metabolismo
12.
Cancer Res ; 72(17): 4372-82, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719069

RESUMO

Cancer cachexia/anorexia is a complex syndrome that involves profound metabolic imbalances and is directly implicated as a cause of death in at least 20% to 30% of all cancers. Brown adipose tissue (BAT) plays a key role in thermogenesis and energy balance and potentially contributes to the physiologic perturbations associated with cachexia. In this study, we investigated the impact of cachexia-inducing colorectal tumor on BAT in mice. We found that brown adipocytes were smaller and exhibited profound delipidation in cachectic tumor-bearing mice. Diurnal expression profiling of key regulators of lipid accumulation and fatty acid ß-oxidation and their corresponding target genes revealed dramatic molecular changes indicative of active BAT. Increased Ucp1, Pbe, and Cpt1α expression at specific points coincided with higher BAT temperatures during the dark cycle, suggestive of a temporal stimulation of thermogenesis in cachexia. These changes persisted when cachectic mice were acclimatized to 28°C confirming inappropriate stimulation of BAT despite thermoneutrality. Evidence of inflammatory signaling also was observed in the BAT as an energetically wasteful and maladaptive response to anorexia during the development of cachexia.


Assuntos
Tecido Adiposo Marrom/metabolismo , Caquexia/metabolismo , Metabolismo dos Lipídeos , Neoplasias/metabolismo , Termogênese , Adenocarcinoma/metabolismo , Tecido Adiposo Marrom/patologia , Animais , Peso Corporal , Caquexia/etiologia , Caquexia/genética , Linhagem Celular Tumoral , Citocinas/metabolismo , Ingestão de Alimentos , Metabolismo Energético , Perfilação da Expressão Gênica , Humanos , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Neoplasias/complicações , Neoplasias/genética , Tamanho do Órgão , Transdução de Sinais , Temperatura , Termogênese/genética
13.
BMC Cancer ; 12: 196, 2012 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-22639861

RESUMO

BACKGROUND: This study examined the association between overall survival and Glutathione S-transferase Pi (GST Pi) expression and genetic polymorphism in stage C colon cancer patients after resection alone versus resection plus 5-fluourouracil-based adjuvant chemotherapy. METHODS: Patients were drawn from a hospital registry of colorectal cancer resections. Those receiving chemotherapy after it was introduced in 1992 were compared with an age and sex matched control group from the preceding period. GST Pi expression was assessed by immunohistochemistry. Overall survival was analysed by the Kaplan-Meier method and Cox regression. RESULTS: From an initial 104 patients treated with chemotherapy and 104 matched controls, 26 were excluded because of non-informative immunohistochemistry, leaving 95 in the treated group and 87 controls. Survival did not differ significantly among patients with low GST Pi who did or did not receive chemotherapy and those with high GST Pi who received chemotherapy (lowest pair-wise p = 0.11) whereas patients with high GST Pi who did not receive chemotherapy experienced markedly poorer survival than any of the other three groups (all pair-wise p <0.01). This result was unaffected by GST Pi genotype. CONCLUSION: Stage C colon cancer patients with low GST Pi did not benefit from 5-fluourouracil-based adjuvant chemotherapy whereas those with high GST Pi did.


Assuntos
Neoplasias do Colo/genética , Neoplasias do Colo/mortalidade , Expressão Gênica , Glutationa S-Transferase pi/genética , Idoso , Quimioterapia Adjuvante , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Resultado do Tratamento
14.
Aging (Albany NY) ; 4(2): 133-43, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22361433

RESUMO

Cancer cachexia is a highly debilitating paraneoplastic disease observed in more than 50% of patients with advanced cancers and directly contributes to 20% of cancer deaths. Loss of skeletal muscle is a defining characteristic of patients with cancer cachexia and is associated with poor survival. The present study reveals the involvement of a myogenic transcription factor Myocyte Enhancer Factor (MEF) 2C in cancer-induced skeletal muscle wasting. Increased skeletal muscle mRNA expression of Suppressor of Cytokine Signaling (Socs) 3 and the IL-6 receptor indicative of active IL-6 signaling was seen in skeletal muscle of mice bearing the Colon 26 (C26) carcinoma. Loss of skeletal muscle structural integrity and distorted mitochondria were also observed using electron microscopy. Gene and protein expression of MEF2C was significantly downregulated in skeletal muscle from C26-bearing mice. MEF2C gene targets myozenin and myoglobin as well as myokinase were also altered during cachexia, suggesting dysregulated oxygen transport capacity and ATP regeneration in addition to distorted structural integrity. In addition, reduced expression of calcineurin was observed which suggested a potential pathway of MEF2C dysregulation. Together, these effects may limit sarcomeric contractile ability and also predispose skeletal muscle to structural instability; associated with muscle wasting and fatigue in cachexia.


Assuntos
Caquexia/etiologia , Caquexia/metabolismo , Músculo Esquelético/metabolismo , Fatores de Regulação Miogênica/metabolismo , Animais , Caquexia/patologia , Calcineurina/metabolismo , Linhagem Celular Tumoral , Regulação para Baixo , Interleucina-6/metabolismo , Fatores de Transcrição MEF2 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Microscopia Eletrônica de Transmissão , Mitocôndrias Musculares/patologia , Modelos Neurológicos , Músculo Esquelético/patologia , Fatores de Regulação Miogênica/genética , Neoplasias Experimentais/complicações , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Sarcômeros/patologia , Transdução de Sinais
15.
Proc Natl Acad Sci U S A ; 109(7): 2302-7, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22308320

RESUMO

Src tyrosine kinase has long been implicated in colon cancer but much remains to be learned about its substrates. The nuclear receptor hepatocyte nuclear factor 4α (HNF4α) has just recently been implicated in colon cancer but its role is poorly defined. Here we show that c-Src phosphorylates human HNF4α on three tyrosines in an interdependent and isoform-specific fashion. The initial phosphorylation site is a Tyr residue (Y14) present in the N-terminal A/B domain of P1- but not P2-driven HNF4α. Phospho-Y14 interacts with the Src SH2 domain, leading to the phosphorylation of two additional tyrosines in the ligand binding domain (LBD) in P1-HNF4α. Phosphomimetic mutants in the LBD decrease P1-HNF4α protein stability, nuclear localization and transactivation function. Immunohistochemical analysis of approximately 450 human colon cancer specimens (Stage III) reveals that P1-HNF4α is either lost or localized in the cytoplasm in approximately 80% of tumors, and that staining for active Src correlates with those events in a subset of samples. Finally, three SNPs in the human HNF4α protein, two of which are in the HNF4α F domain that interacts with the Src SH3 domain, increase phosphorylation by Src and decrease HNF4α protein stability and function, suggesting that individuals with those variants may be more susceptible to Src-mediated effects. This newly identified interaction between Src kinase and HNF4α has important implications for colon and other cancers.


Assuntos
Núcleo Celular/metabolismo , Neoplasias do Colo/enzimologia , Fator 4 Nuclear de Hepatócito/metabolismo , Isoformas de Proteínas/metabolismo , Quinases da Família src/metabolismo , Linhagem Celular , Neoplasias do Colo/patologia , Fator 4 Nuclear de Hepatócito/genética , Humanos , Mimetismo Molecular , Fosforilação , Polimorfismo de Nucleotídeo Único , Isoformas de Proteínas/genética
16.
Histopathology ; 59(6): 1057-70, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22175886

RESUMO

AIMS: This study investigated the association between glutathione S-transferase Pi (GST Pi) expression, histopathology and overall survival in 468 patients after resection of stage C colonic adenocarcinoma. METHODS AND RESULTS: Data were drawn from a prospective hospital registry of consecutive bowel cancer resections with a minimum follow-up of 5 years. Nuclear and cytoplasmic GST Pi expression, assessed by both intensity of staining and percentage of stained cells at both the central part of the tumour and the invasive tumour front, were evaluated retrospectively by tissue microarray immunohistochemistry on archival specimens. The most effective measure of GST Pi expression was the percentage of immunostained nuclei in central tumour tissue, where >40% stained was associated significantly with high grade, invasion beyond the muscularis propria, involvement of a free serosal surface or apical node, and invasion into an adjacent organ or structure. After adjustment of other predictors, GST Pi expression remained independently prognostic for reduced overall survival (hazard ratio 1.4, P = 0.002). CONCLUSIONS: In patients with clinicopathological stage C colonic cancer, GST Pi expression is associated with features of tumour aggressiveness and with reduced overall survival. Further appropriately designed studies should aim to discover whether GST Pi can predict response to adjuvant chemotherapy.


Assuntos
Adenocarcinoma/enzimologia , Biomarcadores Tumorais/análise , Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Glutationa S-Transferase pi/biossíntese , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Neoplasias do Colo/cirurgia , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Análise Serial de Tecidos
17.
Mol Biosyst ; 7(11): 2997-3005, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21808808

RESUMO

Quantitative mass spectrometry using iTRAQ was used to identify differentially expressed proteins from 16 colorectal cancer (CRC) tumours compared to patient-paired adjacent normal mucosa. Over 1400 proteins were identified and quantitated, with 118 determined as differentially expressed by >1.3-fold, with false discovery rate < 0.05. Gene Ontology analysis indicated that proteins with increased expression levels in CRC tumours include those associated with glycolysis, calcium binding, and protease inhibition. Proteins with reduced levels in CRC tumours were associated with loss of ATP production through: (i) reduced ß-oxidation of fatty acids, (ii) reduced NADH production by the tricarboxylic acid cycle and (iii) decreased oxidative phosphorylation activity. Additionally, biosyntheses of glycosaminoglycans and proteoglycans were significantly reduced in tumour samples. Validation experiments using immunoblotting and immunohistochemistry (IHC) showed strong concordance with iTRAQ data suggesting that this workflow is suitable for identifying biomarker candidates. We discuss the uses and challenges of this approach to generate biomarker leads for patient prognostication.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/metabolismo , Mucosa Intestinal/metabolismo , Espectrometria de Massas/métodos , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/química , Neoplasias Colorretais/patologia , Feminino , Humanos , Imuno-Histoquímica , Mucosa Intestinal/química , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Proteômica
18.
Methods Mol Biol ; 781: 311-36, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21877288

RESUMO

Molecular expression patterns have often been used for patient classification in oncology in an effort to improve prognostic prediction and treatment compatibility. This effort is, however, hampered by the highly heterogeneous data often seen in the molecular analysis of cancer. The lack of overall similarity between expression profiles makes it difficult to partition data using conventional data mining tools. In this chapter, the authors introduce a bioinformatics protocol that uses REACTOME pathways and patient-protein network structure (also called topology) as the basis for patient classification.


Assuntos
Biologia Computacional/métodos , Neoplasias/diagnóstico , Neoplasias/metabolismo , Biomarcadores Tumorais/metabolismo , Análise por Conglomerados , Humanos , Neoplasias/terapia , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Software , Espectrometria de Massas em Tandem
19.
Clin Cancer Res ; 17(10): 3170-80, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21498392

RESUMO

PURPOSE: To determine the mechanisms by which tumors situated in extrahepatic sites can cause profound changes in hepatic drug clearance, contributing to altered drug response and chemotherapy resistance. EXPERIMENTAL DESIGN: We studied in wild-type or transgenic CYP3A4 reporter mice implanted with the murine Engelbreth-Holm-Swarm sarcoma changes in nuclear receptor and hepatic transcription factor expression and/or function, particularly related to CYP3A gene regulation. RESULTS: Repression of hepatic CYP3A induction was dramatic and associated with reduced levels of C/EBPß isoforms, impaired pregnane X receptor, and constitutive androstane receptor function. Unexpectedly, extrahepatic tumors strongly reduced nuclear accumulation of retinoid X receptor alpha (RXRα) in hepatocytes, providing a potential explanation for impaired function of nuclear receptors that rely on RXRα dimerization. Profiling revealed 38 nuclear receptors were expressed in liver with 14 showing between 1.5- and four-fold reduction in expression in livers of tumor-bearing animals, including Car, Trß, Lxrß, Pparα, Errα/ß, Reverbα/ß, and Shp. Altered Pparα and γ induction of target genes provided additional evidence of perturbed hepatic metabolic control elicited by extrahepatic tumors. CONCLUSIONS: Extrahepatic malignancy can affect hepatic drug metabolism by nuclear receptor relocalization and decreased receptor expression and function. These findings could aid the design of intervention strategies to normalize drug clearance and metabolic pathways in cancer patients at risk of chemotherapy-induced toxicity or cancer cachexia.


Assuntos
Fígado/metabolismo , Neoplasias/metabolismo , Preparações Farmacêuticas/metabolismo , Receptores Citoplasmáticos e Nucleares/fisiologia , Animais , Linhagem Celular Tumoral , Citocromo P-450 CYP3A/genética , Regulação para Baixo/fisiologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Inativação Metabólica/genética , Óperon Lac , Masculino , Camundongos , Camundongos Transgênicos , Neoplasias/genética , Receptores Citoplasmáticos e Nucleares/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Sarcoma Experimental/genética , Sarcoma Experimental/patologia
20.
Mol Cell Proteomics ; 10(9): M900538MCP200, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20167946

RESUMO

Cancer is well known to be associated with alterations in membrane protein glycosylation (Bird, N. C., Mangnall, D., and Majeed, A. W. (2006) Biology of colorectal liver metastases: A review. J. Surg. Oncol. 94, 68-80; Dimitroff, C. J., Pera, P., Dall'Olio, F., Matta, K. L., Chandrasekaran, E. V., Lau, J. T., and Bernacki, R. J. (1999) Cell surface n-acetylneuraminic acid alpha2,3-galactoside-dependent intercellular adhesion of human colon cancer cells. Biochem. Biophys. Res. Commun. 256, 631-636; and Arcinas, A., Yen, T. Y., Kebebew, E., and Macher, B. A. (2009) Cell surface and secreted protein profiles of human thyroid cancer cell lines reveal distinct glycoprotein patterns. J. Proteome Res. 8, 3958-3968). Equally, it has been well established that tumor-associated inflammation through the release of pro-inflammatory cytokines is a common cause of reduced hepatic drug metabolism and increased toxicity in advanced cancer patients being treated with cytotoxic chemotherapies. However, little is known about the impact of bearing a tumor (and downstream effects like inflammation) on liver membrane protein glycosylation. In this study, proteomic and glycomic analyses were used in combination to determine whether liver membrane protein glycosylation was affected in mice bearing the Engelbreth-Holm Swarm sarcoma. Peptide IPG-IEF and label-free quantitation determined that many enzymes involved in the protein glycosylation pathway specifically; mannosidases (Man1a-I, Man1b-I and Man2a-I), mannoside N-acetylglucosaminyltransferases (Mgat-I and Mgat-II), galactosyltransferases (B3GalT-VII, B4GalT-I, B4GalT-III, C1GalT-I, C1GalT-II, and GalNT-I), and sialyltransferases (ST3Gal-I, ST6Gal-I, and ST6GalNAc-VI) were up-regulated in all livers of tumor-bearing mice (n = 3) compared with nontumor bearing controls (n = 3). In addition, many cell surface lectins: Sialoadhesin-1 (Siglec-1), C-type lectin family 4f (Kupffer cell receptor), and Galactose-binding lectin 9 (Galectin-9) were determined to be up-regulated in the liver of tumor-bearing compared with control mice. Global glycan analysis identified seven N-glycans and two O-glycans that had changed on the liver membrane proteins derived from tumor-bearing mice. Interestingly, α (2,3) sialic acid was found to be up-regulated on the liver membrane of tumor-bearing mice, which reflected the increased expression of its associated sialyltransferase and lectin receptor (siglec-1). The overall increased sialylation on the liver membrane of Engelbreth-Holm Swarm bearing mice correlates with the increased expression of their associated glycosyltransferases and suggests that glycosylation of proteins in the liver plays a role in tumor-induced liver inflammation.


Assuntos
Galactosiltransferases/metabolismo , Glicômica/métodos , Inflamação/metabolismo , Fígado/metabolismo , Manosidases/metabolismo , Neoplasias/metabolismo , Proteoma/metabolismo , Proteômica/métodos , Sarcoma Experimental/metabolismo , Sialiltransferases/metabolismo , Animais , Membrana Celular/genética , Membrana Celular/metabolismo , Galactosiltransferases/genética , Regulação Neoplásica da Expressão Gênica , Glicosilação , Inflamação/etiologia , Inflamação/genética , Lectinas/genética , Lectinas/metabolismo , Fígado/citologia , Masculino , Manosidases/genética , Camundongos , Camundongos Transgênicos , Ácido N-Acetilneuramínico/genética , Ácido N-Acetilneuramínico/metabolismo , Transplante de Neoplasias , Neoplasias/complicações , Neoplasias/genética , Polissacarídeos/genética , Polissacarídeos/metabolismo , Proteoma/genética , Receptores Mitogênicos/genética , Receptores Mitogênicos/metabolismo , Sarcoma Experimental/complicações , Sarcoma Experimental/genética , Sialiltransferases/genética
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