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1.
Clin Kidney J ; 16(12): 2523-2529, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38046044

RESUMO

Background: The aim of this study was to evaluate the impact of peritoneal dialysis (PD) strategy on technique and patient survival. Methods: This was a retrospective, single-center study conducted on consecutive patients with chronic kidney disease who underwent PD between January 2009 and December 2019. The study sample was stratified into four different groups according to PD technique [automated (APD) or manual (CAPD)] and icodextrin use (yes versus no). The primary endpoints were survival of both technique and patient. Results: A total of 531 patients were included in the analysis. Mean ± standard deviation age was 60.6 ± 14.6 years, 68.4% (363) were men and 34.8% (185) had diabetes. The median technique survival time was 19 (15) months. A total of 185 (34.8%), 96 (18.1%), 99 (18.7%) and 151 (28.4%) patients were included in the CAPD/No-Icodextrin, CAPD/Icodextrin, APD/No-Icodextrin and APD/Icodextrin study groups, respectively. Throughout the study, 180 (33.9%) patients underwent renal transplant, 71 (13.4%) were changed to hemodialysis and 151 (28.4%) died. Age [hazard ratio (HR) 0.975, 95% confidence interval (CI) 0.960-0.990, P = .001] and incidence of early peritoneal infection (HR 2.440, 95% CI 1.453-4.098, P = .001) were associated with technique survival, while age (HR 1.029, 95% CI 1.013-1.045, P < .001), Charlson Index (HR 1.192, 95% CI 1.097-1.295, P < 0.001), use of icodextrin (HR 0.421, 95% CI 0.247-0.710, P < .001) and APD/Icodextrin (HR 0.499, 95% CI 0.322-0.803, P = .005) were associated with patient survival. Conclusions: Icodextrin use and APD/Icodextrin had a positive impact on patient survival, while older age and higher Charlson Index had a negative one. Age and incidence of early peritoneal infection significantly impacted on technique survival.

2.
PeerJ ; 11: e15713, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37576513

RESUMO

The red-billed tropicbird, Phaethon aethereus, is a species of seabird native to the Galápagos archipelago, and widely distributed across the neotropics. General health, blood chemistry, and haematology parameters have not been published for this species. Blood analyses were performed on samples drawn from 51 clinically healthy red-billed tropicbirds captured from their burrows at Islote Pitt on San Cristóbal Island in July, 2016 (21) and Daphne Major Island in June, 2017 (30). In the field, a point of care blood analyser (iSTAT) was used to obtain results for HCO3-, pH, pCO2, pO2, TCO2, iCa, Na, K, Cl, Hb, HCT, anion gap, creatinine, glucose and urea nitrogen. Additionally, a portable Lactate PlusTM analyser was used to measure blood lactate, and blood smears were also created in situ. The blood slides were used to estimate leukocyte counts and 100-cell differentials. Alongside these biochemistry and haematology parameters, average heart rate, respiratory rate, body temperature and scaled mass index (calculated from weight and a body measurement) were compared to determine the standard measurements for a healthy individual. The baseline data, and reference intervals reported in this paper are essential to detecting changes in the health of red-billed tropicbirds in the future.


Assuntos
Hematologia , Ácido Láctico , Animais , Temperatura Corporal , Aves , Nível de Saúde , Gases
3.
Nutrients ; 14(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35807767

RESUMO

In chronic kidney disease, systemic inflammation and high serum phosphate (P) promote the de-differentiation of vascular smooth muscle cells (VSMC) to osteoblast-like cells, increasing the propensity for medial calcification and cardiovascular mortality. Vascular microRNA-145 (miR-145) content is essential to maintain VSMC contractile phenotype. Because vitamin D induces aortic miR-145, uremia and high serum P reduce it and miR-145 directly targets osteogenic osterix in osteoblasts, this study evaluated a potential causal link between vascular miR-145 reductions and osterix-driven osteogenic differentiation and its counter-regulation by vitamin D. Studies in aortic rings from normal rats and in the rat aortic VSMC line A7r5 exposed to calcifying conditions corroborated that miR-145 reductions were associated with decreases in contractile markers and increases in osteogenic differentiation and calcium (Ca) deposition. Furthermore, miR-145 silencing enhanced Ca deposition in A7r5 cells exposed to calcifying conditions, while miR-145 overexpression attenuated it, partly through increasing α-actin levels and reducing osterix-driven osteogenic differentiation. In mice, 14 weeks after the induction of renal mass reduction, both aortic miR-145 and α-actin mRNA decreased by 80% without significant elevations in osterix or Ca deposition. Vitamin D treatment from week 8 to 14 fully prevented the reductions in aortic miR-145 and attenuated by 50% the decreases in α-actin, despite uremia-induced hyperphosphatemia. In conclusion, vitamin D was able to prevent the reductions in aortic miR-145 and α-actin content induced by uremia, reducing the alterations in vascular contractility and osteogenic differentiation despite hyperphosphatemia.


Assuntos
Hiperfosfatemia , MicroRNAs , Uremia , Calcificação Vascular , Actinas , Animais , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Camundongos , MicroRNAs/genética , Miócitos de Músculo Liso , Osteogênese/genética , Ratos , Calcificação Vascular/etiologia , Calcificação Vascular/prevenção & controle , Vitamina D/efeitos adversos
4.
Front Med (Lausanne) ; 8: 618286, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113627

RESUMO

Background and Aims: Alterations in novel immune cell subsets, such as angiogenic T cells (Tang), senescent T cells (CD4+CD28null), and monocyte subsets are associated with impaired vascular homeostasis in several inflammatory conditions. However, mediators underlying vascular deterioration in chronic kidney disease (CKD) are poorly characterized. This study assessed their role in the vascular deterioration of CKD using a broad spectrum of surrogate markers ranging from altered functionality to overt calcification. Methods: Tang (CD3+CD31+CXCR4+), CD4+CD28null cells, and monocytes [CD14/CD16 subsets and angiotensin-converting enzyme (ACE) expression] were measured in peripheral blood by flow cytometry in 33 CKD stage 5 patients undergoing peritoneal dialysis (CKD5-PD) and 15 healthy controls (HCs). Analyses were replicated in a hemodialysis cohort. Vascular surrogate markers (including adventitial vasa vasorum, pulse wave velocity, intima-media thickness, and vascular calcification) were assessed by appropriate imaging methods. Results: In CKD5-PD, decreased Tang levels (p < 0.001) were unrelated to clinical features or traditional cardiovascular (CV) risk factors but correlated negatively with troponin T levels (r = -0.550, p = 0.003). Instead, CD4+CD28null frequency was increased (p < 0.001), especially in those with vascular calcifications. Quantitative and qualitative differences were also observed within the monocyte pool, a shift toward CD16+ subsets and ACE expression being found in CKD. Equivalent results were observed in the replication cohort. Each subset associated distinctly with adverse vascular outcomes in univariate and multivariate analyses: while Tang depletion was linked to poor vascular function and subclinical atherosclerosis, increases in CD4+CD28null were associated with overt vascular thickening and calcification. Monocytes were not independently associated with vascular outcomes in CKD patients. Conclusions: Novel T cell and monocyte subsets are altered in CKD. Altered T-cell subpopulations, but not monocytes, exhibited distinct associations with different vascular outcomes in CKD. Tang are emerging biomarkers of subclinical vascular deterioration in CKD.

5.
J Zoo Wildl Med ; 52(2): 671-679, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34130410

RESUMO

Island species are particularly vulnerable to environmental disturbances and introduced pathogens. Conducting health assessments of wild populations in the Galápagos improves the ability of wildlife managers and veterinarians to detect deteriorations in health status. Seabirds in particular are useful species to monitor due to their colonial breeding and wide migration range. Nazca boobies (Sula granti) in a breeding colony at Daphne Major (n = 30) were given physical examinations, and blood samples were collected for hematology and biochemistry using an iSTAT Portable Clinical Analyzer. Female boobies had longer wing length than males, as well as lower blood urea nitrogen, creatinine, and white blood cell counts. This could be attributed to sexual dimorphism or differences in foraging and mating strategies between the sexes. The time between capture and blood collection had a significant inverse relationship on plasma sodium, potassium, hemoglobin, anion gaps, and lymphocyte counts, suggesting that blood sampling in Nazca boobies should be done in less than 5 m to avoid the impacts of stress on hematological parameters. This is the first health assessment on the breeding colony of Nazca boobies at Daphne Major, and the results can inform future monitoring in this species as well as other sulids.


Assuntos
Doenças das Aves/diagnóstico , Aves/sangue , Animais , Doenças das Aves/epidemiologia , Equador/epidemiologia , Feminino , Testes Hematológicos/veterinária , Masculino , Testes Sorológicos/veterinária
6.
Arthritis Rheumatol ; 73(3): 401-413, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33001576

RESUMO

OBJECTIVE: Eicosanoids modulate inflammation via complex networks involving different pathways and downstream mediators, including oxylipins. Although altered eicosanoids are linked to rheumatoid arthritis (RA), suggesting that metabolization is enhanced, the role of oxylipins in disease stratification remains unexplored. This study was undertaken to characterize oxylipin networks during the earliest stages of RA and evaluate their associations with clinical features and treatment outcomes. METHODS: In total, 60 patients with early RA (according to the American College of Rheumatology/European League Against Rheumatism 2010 criteria), 11 individuals with clinically suspect arthralgia (CSA), and 28 healthy control subjects were recruited. Serum samples were collected at the time of onset. In the early RA group, 50 patients who had not been exposed to disease-modifying antirheumatic drug (DMARD) or glucocorticoid treatment at the time of recruitment were prospectively followed up at 6 and 12 months after having received conventional synthetic DMARDs. A total of 75 oxylipins, mostly derived from arachidonic, eicosapentanoic, and linoleic acids, were identified in the serum by liquid chromatography tandem mass spectrometry. RESULTS: Univariate analyses demonstrated differences in expression patterns of 14 oxylipins across the RA, CSA, and healthy control groups, with each exhibiting a different trajectory. Network analyses revealed a strong grouping pattern of oxylipins in RA patients, whereas in individuals with CSA, a fuzzy network of oxylipins with higher degree and closeness was found. Partial least-squares discriminant analyses yielded variable important projection scores of >1 for 22 oxylipins, which allowed the identification of 2 clusters. Cluster usage differed among the groups (P = 0.003), and showed associations with disease severity and low rates of remission at 6 and 12 months in RA patients who were initially treatment-naive. Pathway enrichment analyses revealed different precursors and pathways between the groups, highlighting the relevance of the arachidonic acid pathway in individuals with CSA and the lipooxygenase pathway in patients with early RA. In applying distinct oxylipin signatures, subsets of seropositive and seronegative RA could be identified. CONCLUSION: Oxylipin networks differ across stages during the earliest phases of RA. These distinct oxylipin networks could potentially elucidate pathways with clinical relevance for disease progression, clinical heterogeneity, and treatment response.


Assuntos
Artrite Reumatoide/sangue , Oxilipinas/sangue , Adulto , Idoso , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Estudos de Casos e Controles , Análise Discriminante , Progressão da Doença , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade
7.
J Clin Med ; 9(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32752190

RESUMO

This study aimed at evaluating the clinical relevance of glycoprotein profiles during the earliest phases of rheumatoid arthritis (RA) as biomarkers of cardiovascular (CV) risk and treatment response. Then, GlycA and GlycB serum levels were measured using 1H-nuclear magnetic resonance in 82 early RA patients, 14 clinically-suspect arthralgia (CSA), and 28 controls. Serum glycosyltransferase activity was assessed by a colorimetric assay. Subclinical CV disease was assessed by Doppler-ultrasound. We found that GlycA and GlycB serum levels were increased in RA (both p < 0.001), but not in CSA, independently of cardiometabolic risk factors. Increased serum glycosyltransferase activity paralleled GlycA (r = 0.405, p < 0.001) and GlycB levels (r = 0.327, p = 0.005) in RA. GlycA, but not GlycB, was associated with atherosclerosis occurrence (p = 0.012) and severity (p = 0.001). Adding GlycA to the mSCORE improved the identification of patients with atherosclerosis over mSCORE alone, increasing sensitivity (29.7 vs. 68.0%) and accuracy (55.8 vs. 76.6%) and allowing reclassification into more appropriate risk categories. GlycA-reclassification identified patients with impaired lipoprotein metabolism. Finally, baseline GlycA levels predicted poor clinical response upon anti-rheumatic treatment at 6 and 12 months in univariate and multivariate analysis. In sum, increased GlycA levels during the earliest stage of RA can be considered a powerful biomarker for CV risk stratification and treatment response.

8.
J Zoo Wildl Med ; 50(4): 1026-1030, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926542

RESUMO

The Galápagos shearwater, Puffinus subalaris, is a seabird endemic to the Galápagos archipelago. Hematology, blood chemistry, and general health parameters have not been published for this species. Analyses were run on blood samples drawn from 20 clinically healthy Galápagos shearwaters captured by hand at their nests at Islote Pitt on San Cristóbal Island in July 2016. A portable blood analyzer (iSTAT) was used to obtain near immediate field results for pH, pO2, pCO2, TCO2, HCO3 -, hematocrit, hemoglobin, sodium, potassium, chloride, ionized calcium, creatinine, urea nitrogen, anion gap, and glucose. Blood lactate was measured using a portable Lactate Plus analyzer. The reported results provide baseline data that can be used for comparisons among populations and in detecting changes in health status among Galápagos shearwaters.


Assuntos
Bicarbonatos/sangue , Aves/sangue , Dióxido de Carbono/sangue , Hematócrito/veterinária , Oxigênio/sangue , Equilíbrio Ácido-Base , Animais , Glicemia , Cálcio/sangue , Cloretos/sangue , Creatinina/sangue , Hemoglobinas , Concentração de Íons de Hidrogênio , Lactatos/sangue , Potássio/sangue , Sódio/sangue
9.
Conserv Physiol ; 8(1): coaa064, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-34336215

RESUMO

The swallow-tailed gull, Creagrus furcatus, is a seabird endemic to the Galápagos archipelago. In general health, blood chemistry and haematology, parameters have not been published for this species. Blood analyses were run on samples drawn from 58 clinically healthy swallow-tailed gulls captured at Islote Pitt on San Cristóbal Island in July 2016 (28) and South Plaza Island in June 2017 (30). A point of care blood analyzer (iSTAT) was used in the field to obtain results for HCO3 -, pH, pCO2, pO2, TCO2, anion gap, chloride, creatinine, glucose, haematocrit, haemoglobin, ionized calcium, potassium, sodium and urea nitrogen. A portable Lactate Plus™ analyzer was used to measure lactate. The baseline data reported is valuable for comparisons amongst different populations in the archipelago and to detect changes in health status of Galápagos swallow-tailed gulls.

10.
Sci Rep ; 9(1): 17810, 2019 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-31780737

RESUMO

In chronic kidney disease (CKD), hyperphosphatemia-induced inflammation aggravates vascular calcification (VC) by increasing vascular smooth muscle cell (VSMC) osteogenic differentiation, ADAM17-induced renal and vascular injury, and TNFα-induction of neutral-sphingomyelinase2 (nSMase2) to release pro-calcifying exosomes. This study examined anti-inflammatory ß-glucans efficacy at attenuating systemic inflammation in health, and renal and vascular injury favoring VC in hyperphosphatemic CKD. In healthy adults, dietary barley ß-glucans (Bßglucans) reduced leukocyte superoxide production, inflammatory ADAM17, TNFα, nSMase2, and pro-aging/pro-inflammatory STING (Stimulator of interferon genes) gene expression without decreasing circulating inflammatory cytokines, except for γ-interferon. In hyperphosphatemic rat CKD, dietary Bßglucans reduced renal and aortic ADAM17-driven inflammation attenuating CKD-progression (higher GFR and lower serum creatinine, proteinuria, kidney inflammatory infiltration and nSMase2), and TNFα-driven increases in aortic nSMase2 and calcium deposition without improving mineral homeostasis. In VSMC, Bßglucans prevented LPS- or uremic serum-induced rapid increases in ADAM17, TNFα and nSMase2, and reduced the 13-fold higher calcium deposition induced by prolonged calcifying conditions by inhibiting osteogenic differentiation and increases in nSMase2 through Dectin1-independent actions involving Bßglucans internalization. Thus, dietary Bßglucans inhibit leukocyte superoxide production and leukocyte, renal and aortic ADAM17- and nSMase2 gene expression attenuating systemic inflammation in health, and renal injury and aortic calcification despite hyperphosphatemia in CKD.


Assuntos
Proteína ADAM17/antagonistas & inibidores , Hordeum/química , Insuficiência Renal Crônica/dietoterapia , Esfingomielina Fosfodiesterase/antagonistas & inibidores , Calcificação Vascular/dietoterapia , beta-Glucanas/uso terapêutico , Adulto , Animais , Modelos Animais de Doenças , Feminino , Voluntários Saudáveis , Humanos , Inflamação/dietoterapia , Masculino , Camundongos , Pessoa de Meia-Idade , Células RAW 264.7 , Ratos , Ratos Sprague-Dawley , Adulto Jovem , beta-Glucanas/farmacologia
11.
Sci Rep ; 9(1): 13230, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31519925

RESUMO

Inflammation is central to chronic kidney disease (CKD) pathogenesis and vascular outcomes, but the exact players remain unidentified. Since low density granulocytes (LDGs) are emerging mediators in inflammatory conditions, we aimed to evaluate whether LDGs may be altered in CKD and related to clinical outcomes as biomarkers. To his end, LDGs subsets were measured in peripheral blood by flow cytometry and confocal microscopy in 33 CKD patients undergoing peritoneal dialysis and 15 healthy controls (HC). Analyses were replicated in an additional cohort. DEF3 (marker of early granulopoiesis) gene expression on PBMCs was quantified by qPCR. Total CD15+ LDGs and both CD14lowCD16+ and CD14-CD16- subsets were expanded in CKD. The relative frequency of the CD14-CD16- subpopulation was higher among the CD15+ pool in CKD. This alteration was stable over-time. The increased CD14-CD16-CD15+ paralleled Kauppila scores and DEF3 expression, whereas no association was found with CD14lowCD16+ CD15+. Both subsets differed in their CD11b, CD10, CD35, CD31, CD62L, IFNAR1 and CD68 expression, FSC/SSC features and nuclear morphology, pointing to different origins and maturation status. In conclusion, LDGs were expanded in CKD showing a skewed distribution towards a CD14-CD16-CD15+ enrichment, in association with vascular calcification. DEF3 expression in PBMC can be a marker of LDG expansion.


Assuntos
Biomarcadores/análise , Granulócitos/patologia , Inflamação/complicações , Insuficiência Renal Crônica/patologia , Calcificação Vascular/complicações , Adulto , Idoso , Feminino , Humanos , Leucócitos Mononucleares/patologia , Masculino , Pessoa de Meia-Idade , Monócitos/patologia , Neutrófilos/patologia , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/etiologia , Adulto Jovem
12.
Conserv Physiol ; 6(1): coy034, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30026947

RESUMO

The great frigatebird, Fregata minor, is a widely distributed seabird native to the Galápagos archipelago. Haematology and blood chemistry parameters have been published for this species but not from the San Cristóbal and North Seymour great frigatebird breeding colonies. Analyses were run on blood samples drawn from 25 great frigatebirds captured by hand at their nests at Punta Pitt on San Cristóbal Island and 30 birds on North Seymour Island, Galápagos Islands. A portable blood analyser (iSTAT) was used to obtain near immediate field results for pH, pO2, pCO2, TCO2, HCO3- , haematocrit (Hct), haemoglobin (Hb), sodium (Na), potassium (K), chloride (Cl), ionized calcium (iCa), creatinine, urea nitrogen, anion gap and glucose. Blood lactate was measured using a portable Lactate Plus™ analyser. Average heart rate, respiratory rate, body weight, body temperature, biochemistry and haematology parameters were comparable to healthy individuals of other Fregatidae. The reported results provide baseline data that can be used for comparisons among populations and in detecting changes in health status among Galápagos great frigatebirds.

13.
J Zoo Wildl Med ; 48(4): 1230-1233, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29297841

RESUMO

The red-footed booby ( Sula sula) is a widely distributed sulid native to the Galápagos archipelago. Hematology and blood chemistry parameters have been published for this species, but not from the San Cristóbal rookery. Analyses were run on blood samples drawn from 31 manually restrained red-footed boobies that were captured by hand from their nests at Punta Pitt on San Cristóbal Island. A portable blood analyzer (iSTAT) was used to obtain near immediate field results for pH, partial pressure of oxygen, partial pressure of carbon dioxide, bicarbonate, hematocrit, hemoglobin, sodium, potassium, ionized calcium, and glucose. Blood lactate was measured using a portable Lactate Plus™ analyzer. Average heart rate, respiratory rate, body weight, body temperature, and biochemistry and hematology parameters were comparable to those of healthy individuals of other sulids. The reported results provide baseline data that can be used for comparisons among populations and in detecting changes in health status among Galápagos red-footed boobies.


Assuntos
Bicarbonatos/sangue , Aves/sangue , Dióxido de Carbono/sangue , Oxigênio/sangue , Exame Físico/veterinária , Animais , Glicemia , Cálcio/sangue , Equador , Hematócrito , Hemoglobinas , Potássio/sangue , Valores de Referência , Sódio/sangue
14.
Chemotherapy ; 60(4): 211-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25871785

RESUMO

Otitis media (OM) is one of the most common infections in children, Streptococcus pneumoniae and nontypable Haemophilus influenzae being the two most common pathogens isolated in the middle ear fluid (MEF) of children with OM. Cefditoren is a third-generation cephalosporin with broad-spectrum antibacterial activity, including activity against those pathogens commonly causing OM, with enhanced stability against common ß-lactamases. The main objective of this study was to evaluate the in vitro activity of cefditoren against pathogens collected from the MEF of Costa Rican children with OM between 2006 and 2011. A total of 715 samples were analyzed. Among the 89 S. pneumoniae strains that were penicillin-nonsusceptible, only 7% were cefditoren-resistant according to Spanish Regulatory Agency criteria; among the H. influenza and M. catarrhalis isolates obtained, 100 and 90% of the isolates, respectively, were cefditoren-susceptible. MIC50/90 against the 207 PCV-13 S. pneumoniae serotyped strains and the 79 serotypes not covered by PCV-13 for cefditoren were 0.03/1 and 0.03/0.12 mg/l, respectively. For both amoxicillin-susceptible and resistant H. influenzae strains, the MIC range against cefditoren was from ≤0.015 to 0.06 mg/l as well. In conclusion, the confirmation of the wide spectrum of activity of cefditoren and its intrinsic strength against resistant strains allows us to suggest that cefditoren might be included as one of the best choices among antibiotics that are widely used in empiric therapy for OM in pediatric patients.


Assuntos
Antibacterianos/uso terapêutico , Cefalosporinas/uso terapêutico , Orelha Média/microbiologia , Otite Média/tratamento farmacológico , Otite Média/epidemiologia , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Criança , Pré-Escolar , Costa Rica , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/fisiologia , Orelha Média/efeitos dos fármacos , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana/métodos , Otite Média/diagnóstico , Streptococcus pneumoniae/efeitos dos fármacos , Streptococcus pneumoniae/isolamento & purificação , Streptococcus pneumoniae/fisiologia
15.
J Clin Invest ; 122(5): 1849-68, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22505459

RESUMO

Malignant progression in cancer requires populations of tumor-initiating cells (TICs) endowed with unlimited self renewal, survival under stress, and establishment of distant metastases. Additionally, the acquisition of invasive properties driven by epithelial-mesenchymal transition (EMT) is critical for the evolution of neoplastic cells into fully metastatic populations. Here, we characterize 2 human cellular models derived from prostate and bladder cancer cell lines to better understand the relationship between TIC and EMT programs in local invasiveness and distant metastasis. The model tumor subpopulations that expressed a strong epithelial gene program were enriched in highly metastatic TICs, while a second subpopulation with stable mesenchymal traits was impoverished in TICs. Constitutive overexpression of the transcription factor Snai1 in the epithelial/TIC-enriched populations engaged a mesenchymal gene program and suppressed their self renewal and metastatic phenotypes. Conversely, knockdown of EMT factors in the mesenchymal-like prostate cancer cell subpopulation caused a gain in epithelial features and properties of TICs. Both tumor cell subpopulations cooperated so that the nonmetastatic mesenchymal-like prostate cancer subpopulation enhanced the in vitro invasiveness of the metastatic epithelial subpopulation and, in vivo, promoted the escape of the latter from primary implantation sites and accelerated their metastatic colonization. Our models provide new insights into how dynamic interactions among epithelial, self-renewal, and mesenchymal gene programs determine the plasticity of epithelial TICs.


Assuntos
Células Epiteliais/patologia , Transição Epitelial-Mesenquimal , Invasividade Neoplásica/patologia , Metástase Neoplásica/patologia , Animais , Antígenos de Diferenciação/genética , Antígenos de Diferenciação/metabolismo , Caderinas/genética , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Forma Celular , Técnicas de Cocultura , Células Epiteliais/fisiologia , Transição Epitelial-Mesenquimal/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Estadiamento de Neoplasias , Transplante de Neoplasias , Neoplasias da Próstata , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Fatores de Transcrição da Família Snail , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Proteína 1 Relacionada a Twist/genética , Proteína 1 Relacionada a Twist/metabolismo , Neoplasias da Bexiga Urinária , Homeobox 1 de Ligação a E-box em Dedo de Zinco
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