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1.
Int J Surg Pathol ; 29(7): 794-797, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33733892

RESUMO

Urothelial carcinoma usually shows divergent differentiation and variant histology with squamous and glandular morphology being most common. In this report, we present a case of divergent malignant melanocytic differentiation in a high-grade urothelial carcinoma. A 98-year-old East Asian woman with an anterior bladder wall mass underwent resection, which revealed a high-grade poorly differentiated tumor. A minor component of high-grade papillary urothelial carcinoma and carcinoma in situ is also present. The majority of the tumor cells are morphologically and immunohistochemically consistent with melanoma, a minority of cells are positive for urothelial markers, and rare cells coexpress both melanocytic and urothelial markers. Cells that express melanocytic markers or urothelial markers are intimately admixed together. Taken together, a diagnosis of high-grade urothelial carcinoma with malignant melanocytic differentiation was rendered. This is the first report in the literature of malignant melanocytic differentiation in a high-grade urothelial carcinoma, a finding that may have important diagnostic and therapeutic implications.


Assuntos
Carcinoma de Células de Transição/diagnóstico , Melanoma/diagnóstico , Neoplasias Complexas Mistas/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Bexiga Urinária/patologia , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biópsia , Carcinoma de Células de Transição/patologia , Carcinoma de Células de Transição/cirurgia , Diferenciação Celular , Procedimentos Cirúrgicos de Citorredução , Feminino , Humanos , Melanoma/patologia , Melanoma/cirurgia , Gradação de Tumores , Neoplasias Complexas Mistas/patologia , Neoplasias Complexas Mistas/cirurgia , Bexiga Urinária/diagnóstico por imagem , Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/cirurgia , Urotélio/diagnóstico por imagem , Urotélio/patologia , Urotélio/cirurgia
2.
Urol Int ; 102(3): 262-268, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30630187

RESUMO

OBJECTIVE: To present our technique of laparoscopic pyeloplasty (LP) with concomitant pyelolithotomy in ureteropelvic junction obstruction (UPJO) complicated by renal calculi and compare outcome with a group of UPJO patients undergoing modified LP without coexistent calculi. MATERIALS AND METHODS: We retrospectively reviewed the charts of 51 UPJO patients undergoing modified LP from January 2013 to November 2016 at our institution. Sixteen patients were diagnosed as UPJO with coexistent ipsilateral renal calculi and underwent pyelolithotomy using our modified technique at the time of modified LP. The outcome data of this group were compared with those of 16 matched patients undergoing modified LP without calculi. RESULTS: No conversion to open surgery occurred. The mean operative time for modified LP and pyelolithotomy was 151.6 min, while the mean operative time for modified LP was 137.6 min (p = 0.21). Additionally, no differences in estimated blood loss (p = 0.96) or postoperative complications (p = 1.00) were observed between the 2 groups. The stone-free rate was 100%. During a mean follow-up of 27.1 months, there were no recurrent calculi or secondary UPJO. CONCLUSIONS: The combination of our novel flexible guiding tube and modified suture technique provides a practical and economic approach with satisfying outcome in the treating of UPJO with concomitant renal calculi.


Assuntos
Cistoscópios , Cistoscopia/métodos , Cálculos Renais/cirurgia , Laparoscopia/métodos , Obstrução Ureteral/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Adulto , Desenho de Equipamento , Feminino , Humanos , Rim/cirurgia , Pelve Renal/cirurgia , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Ureter/cirurgia , Adulto Jovem
3.
Urology ; 124: 286-291, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30468754

RESUMO

OBJECTIVE: To illustrate our technique to construct the Institute of Urology Peking University (IUPU) orthotopic ileal bladder and present our initial experience. METHODS: From August 2017 to April 2018, 12 patients with bladder cancer underwent radical cystectomy (RC), pelvic lymph node dissection and extracorporeal construction of an IUPU neobladder (IUPUB) by an experienced surgeon. We present the demographic, clinicopathologic, perioperative, and follow-up data. We also describe our step-by-step surgical technique for the IUPUB in this article. RESULTS: Laparoscopic RC with an extracorporeal IUPUB was successfully accomplished in 11 patients, and 1 patient was converted to open RC with an IUPUB. The median total operative time and median time spent suturing the pouch were 248 minutes and 23 minutes, respectively. The median estimated blood loss was 150 mL. The median time to recovery of bowel function (tolerance of a liquid diet) was 3½ days. The urinary catheter was removed on post-operative day 21 in 10 patients. The ureteral stents and stoma catheter were removed on day 7 after cystography. At a median followup of 7½ months, 2 patients had early complications (<30 days), and no major complications (grade ≥ 3) occurred. The follow-up outcomes were satisfactory. The limitations included the small sample size and short-term outcomes. CONCLUSION: Our technique of constructing the IUPUB is feasible and safe. The operative time and early complication rates are acceptable.


Assuntos
Cistectomia/métodos , Laparoscopia , Neoplasias da Bexiga Urinária/cirurgia , Coletores de Urina , Feminino , Seguimentos , Humanos , Íleo/transplante , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Procedimentos Cirúrgicos Urológicos/métodos
4.
Sci Rep ; 8(1): 17525, 2018 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-30510214

RESUMO

Despite the importance of nitrogen (N) deposition for soil biogeochemical cycle, how N addition affects the accumulation of humic substances in decomposing litter still remains poorly understood. A litterbag experiment was conducted to assess the potential effects of N addition (0 kg·N·ha-1·year-1, 20 kg·N·ha-1·year-1 and 40 kg·N·ha-1·year-1) on mass remaining and humification of two leaf litter (Michelia wilsonii and Camptotheca acuminata) in a subtropical forest of southwestern China. After one year of decomposition, litter mass was lost by 38.1-46.5% for M. wilsonii and 61.7-74.5% for C. acuminata, respectively. Humic substances were declined by 12.1-23.8% in M. wilsonii and 29.1-35.5% in C. acuminata, respectively. Nitrogen additions tended to reduce mass loss over the experimental period. Moreover, N additions did not affect the concentrations of humic substances and humic acid in the early stage but often increased them in the late stage. The effect of N addition on the accumulation of humic substances was stronger for C. acuminate litter than in M. wilsonii litter. Litter N and P contents showed positive correlations with concentrations of humic substances and fulvic acid. Our results suggest that both litter quality and season-driven environmental changes interactively mediate N impacts on litter humification. Such findings have important implications for carbon sequestration via litter humification in the subtropical forest ecosystems experiencing significant N deposition.

5.
Urology ; 108: 201-206, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28739403

RESUMO

OBJECTIVE: To evaluate the feasibility of ileal ureter replacement combined with Boari flap-psoas hitch procedure for the management of full-length ureteral defects (>20 cm). METHODS: Three patients diagnosed with full-length ureteral defect were treated with our technique performed by a single surgeon between January 2015 to January 2016. All the patients had borderline renal function preoperatively. In each case, the ureteral reconstruction was performed by combining ileal ureter replacement with Boari flap-psoas hitch. Data on indications for surgery, intraoperative and postoperative outcomes, and changes in renal function were collected. RESULTS: Surgery was performed successfully with an operation duration between 210 and 250 minutes. The mean estimated blood loss was 230 mL. The mean length of hospital stay was 11 days, and no major complications (grade ≥3) occurred. Postoperative follow-up showed radiological resolution of hydronephrosis and improved renal function in all 3 patients. CONCLUSION: Ileal ureter replacement combined with Boari flap-psoas hitch is a feasible option for bridging full-length ureteral defects. This technique minimizes the length of ileal graft required as well as limitations concerning patient selection. Larger series with longer follow-up to confirm the value of the technique are warranted.


Assuntos
Íleo/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Músculos Psoas/transplante , Reimplante/métodos , Retalhos Cirúrgicos , Obstrução Ureteral/cirurgia , Procedimentos Cirúrgicos Urológicos Masculinos/métodos , Adulto , Estudos de Viabilidade , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Ureter/cirurgia , Obstrução Ureteral/diagnóstico
6.
Sci Rep ; 7(1): 4777, 2017 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-28684874

RESUMO

How forest management practice impacts the temperature response of soil carbon decomposition remains unclear in Tibetan boreal forests. Here, an experiment was conducted to compare soil carbon decomposition of two layers (organic and mineral) in three Tibetan forests (natural forest, NF; secondary forest, SF; spruce plantation, PF). Soils were incubated at two temperatures (10 °C and 20 °C) for 219 days. Increased temperature often stimulated carbon decomposition rates of organic layer but did not affect them in the mineral soils. Soil carbon decomposition rates in the organic layer followed a pattern of NF > SF > PF over the incubation period. Regardless of forest type, soil carbon decomposition rates and temperature coefficient (Q 10) were higher in the organic layers compared to mineral soils. Moreover, forest type conversion increased Q 10 values in each soil layer. Taken together, our results suggest that forest management practice has much stronger impacts on biochemical properties in the organic layers relative to mineral soils. Moreover, the temperature responses of soil carbon decomposition depend largely on forest management practice and soil layer in this specific area.


Assuntos
Carbono/metabolismo , Florestas , Solo/química , Biomassa , Conservação dos Recursos Naturais , Temperatura , Tibet
7.
Int Neurourol J ; 20(Suppl 2): S120-130, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27915475

RESUMO

Progress has been made in applying genetic information to disease management in the postgenomic era, and precision medicine is emerging in prostate cancer management. The prostate health index, the 4-kallikrein (4K) score, and the PCA3, TMPRSS2- ERG, and Prostarix tests have potential for refining prostate cancer screening in conjunction with traditional prostate-specific antigen testing. The Confirm MDx and PCA3 tests have shown promise in identifying men who need be rebiopsied after a primary negative biopsy. Oncotype DX, Prolaris, the biopsy-based Decipher prostate cancer test, and ProMark may improve predictive risk stratification in addition to the traditional Gleason score and tumor stage. Decipher and Prolaris may predict biochemical recurrence and metastasis after radical prostatectomy and possibly help identify patients who need adjuvant therapy. Androgen receptor splice variant 7 appears effective in guiding the selection of second hormonal manipulation with abiraterone or enzalutamide versus chemotherapy when treating metastatic castration-resistant prostate cancer.

8.
BMC Public Health ; 12: 1043, 2012 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-23198694

RESUMO

BACKGROUND: Diabetes has become a major public health problem in China. Support of patient self-management is a key component of effective diabetes care and improved patient outcomes. A series of peer-led community-based disease-specific self-management programs including diabetes have been widely disseminated in urban communities of Shanghai since 1999. However, the strategy of using trained lay leaders to support patient self-management faces challenges in rural communities in Shanghai. This study developed a Chinese diabetes group visit program as an alternative approach to support patient self-management and examined its effectiveness on self-management behaviors, self-efficacy and health status for patients with type 2 diabetes in rural communities of Shanghai. METHODS: 208 patients with type 2 diabetes aged 35-80 years were randomly assigned to the intervention group (n=119) of 12 monthly group visit sessions or to a control group (n=89) of usual care. The trial was undertaken in two rural communities in Shanghai, China. Randomization and allocation to study group were carried out by using a random number table. Analysis of covariance was used to compare changes in the 17 self-management behavior, self-efficacy and health status related variables in two groups at 12 months' follow-up based on 176 patients (n=98; n=78). RESULTS: Compared with controls, the intervention patients, on average, increased their duration of aerobic exercise by more than 40 minutes per week (p=0.001); had significant increase of 0.71 in mean score on self-efficacy to manage diabetes (p=0.02); and had significant improvements in measures of illness intrusiveness and systolic blood pressure. The intervention patients attended an average of 10.1 of the 12 program sessions with 75.6% of them attended 10 and more sessions. CONCLUSION: The Chinese diabetes group visit model is a feasible, acceptable and effective alternative for supporting diabetes patient self-management in Chinese rural communities. The model requires larger studies to determine its effect on blood glucose control and health care utilization. TRIAL REGISTRATION: ISRCTN87909028.


Assuntos
Automonitorização da Glicemia , Diabetes Mellitus Tipo 2/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , China , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/prevenção & controle , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , População Rural , Autoeficácia
9.
Urology ; 79(2): e12-4, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21705047

RESUMO

Calycostomy is a procedure used for an inaccessible renal pelvis during pyeloplasty. We report the first case of using an anterior calycostomy to repair a ureterojejeunal fistula in a transverse colon conduit in which the ureter and pelvis were not accessible because of intense fibrosis.


Assuntos
Colo Transverso/cirurgia , Fístula Intestinal/cirurgia , Doenças do Jejuno/cirurgia , Pelve Renal/cirurgia , Complicações Pós-Operatórias/cirurgia , Doenças Ureterais/cirurgia , Derivação Urinária/efeitos adversos , Fístula Urinária/cirurgia , Adulto , Anastomose Cirúrgica/métodos , Reação a Corpo Estranho/etiologia , Humanos , Linfoma/tratamento farmacológico , Linfoma/radioterapia , Masculino , Complicações Pós-Operatórias/etiologia , Pielonefrite/complicações , Fibrose Retroperitoneal/complicações , Stents , Obstrução Ureteral/etiologia , Obstrução Ureteral/cirurgia
10.
J Bone Miner Res ; 22(2): 274-85, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17129178

RESUMO

UNLABELLED: We report the phenotype of mice with targeted disruption of the Trpv6 (Trpv6 KO) epithelial calcium channel. The mice exhibit disordered Ca(2+) homeostasis, including defective intestinal Ca(2+) absorption, increased urinary Ca(2+) excretion, decreased BMD, deficient weight gain, and reduced fertility. Although our Trpv6 KO affects the closely adjacent EphB6 gene, the phenotype reported here is not related to EphB6 dysfunction. INTRODUCTION: The mechanisms underlying intestinal Ca(2+) absorption are crucial for overall Ca(2+) homeostasis, because diet is the only source of all new Ca(2+) in the body. Trpv6 encodes a Ca(2+)-permeable cation channel responsible for vitamin D-dependent intestinal Ca(2+) absorption. Trpv6 is expressed in the intestine and also in the skin, placenta, kidney, and exocrine organs. MATERIALS AND METHODS: To determine the in vivo function of TRPV6, we generated mice with targeted disruption of the Trpv6 (Trpv6 KO) gene. RESULTS: Trpv6 KO mice are viable but exhibit disordered Ca(2+) homeostasis, including a 60% decrease in intestinal Ca(2+) absorption, deficient weight gain, decreased BMD, and reduced fertility. When kept on a regular (1% Ca(2+)) diet, Trpv6 KO mice have deficient intestinal Ca(2+) absorption, despite elevated levels of serum PTH (3.8-fold) and 1,25-dihydroxyvitamin D (2.4-fold). They also have decreased urinary osmolality and increased Ca(2+) excretion. Their serum Ca(2+) is normal, but when challenged with a low (0.25%) Ca(2+) diet, Trpv6 KO mice fail to further increase serum PTH and vitamin D, ultimately developing hypocalcemia. Trpv6 KO mice have normal urinary deoxypyridinoline excretion, although exhibiting a 9.3% reduction in femoral mineral density at 2 months of age, which is not restored by treatment for 1 month with a high (2%) Ca(2+) "rescue" diet. In addition to their deranged Ca(2+) homeostasis, the skin of Trpv6 KO mice has fewer and thinner layers of stratum corneum, decreased total Ca(2+) content, and loss of the normal Ca(2+) gradient. Twenty percent of all Trpv6 KO animals develop alopecia and dermatitis. CONCLUSIONS: Trpv6 KO mice exhibit an array of abnormalities in multiple tissues/organs. At least some of these are caused by tissue-specific mechanisms. In addition, the kidneys and bones of Trpv6 KO mice do not respond to their elevated levels of PTH and 1,25-dihydroxyvitamin D. These data indicate that the TRPV6 channel plays an important role in Ca(2+) homeostasis and in other tissues not directly involved in this process.


Assuntos
Canais de Cálcio/fisiologia , Cálcio/metabolismo , Homeostase , Canais de Cátion TRPV/fisiologia , Animais , Sequência de Bases , Canais de Cálcio/genética , Primers do DNA , Absorção Intestinal , Camundongos , Camundongos Knockout , Hormônio Paratireóideo/sangue , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Canais de Cátion TRPV/genética
11.
Am J Pathol ; 169(6): 2209-22, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17148682

RESUMO

Caveolins are integral membrane proteins that localize predominantly to lipid rafts, where they oligomerize to form flask-shaped organelles termed caveolae and play important roles in membrane trafficking, signal transduction, and other cellular processes. To investigate potential roles for caveolin-1 (cav-1) in development, cav-1alpha and -1beta cDNAs were functionally characterized in the zebrafish. Cav-1alpha and -1beta mRNAs exhibited overlapping but distinct expression patterns throughout embryogenesis. Targeted depletion of either Cav-1 isoform, using antisense morpholino oligomers, resulted in a substantial loss of caveolae and dramatic neural, eye, and somite defects by 12 hours after fertilization, the time at which mRNA levels of both isoforms substantially increased in wild-type animals. Morphant phenotypes were rescued by injection of homotypic (cav-1alpha/cav-1alpha) but not heterotypic (cav-1alpha/cav-1beta) zebrafish and human cav-1 cRNAs, revealing nonredundant and evolutionarily conserved functions for the individual Cav-1 isoforms. Mutation of a known Cav-1 phosphorylation site unique to Cav-1alpha (Y14-->F) resulted in a failure to rescue the cav-1alpha morphant phenotype, verifying an essential role for Cav-1alpha specifically and implicating this residue in early developmental functions. Cav-1alpha and -1beta morphants also exhibited disruption in the actin cytoskeleton. These results support important and previously unanticipated roles for the Caveolin-1 isoforms in vertebrate organogenesis.


Assuntos
Caveolina 1/fisiologia , Proteínas de Peixe-Zebra/fisiologia , Peixe-Zebra/embriologia , Actinas/metabolismo , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Padronização Corporal , Cavéolas/química , Caveolina 1/genética , Caveolina 1/metabolismo , Linhagem Celular , Humanos , Microscopia Eletrônica de Transmissão , Dados de Sequência Molecular , Notocorda/irrigação sanguínea , Notocorda/embriologia , Fosforilação , Isoformas de Proteínas , RNA Mensageiro , Homologia de Sequência de Aminoácidos , Somitos/metabolismo , Distribuição Tecidual , Transfecção , Peixe-Zebra/metabolismo
12.
J Clin Invest ; 115(4): 959-68, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15776112

RESUMO

Lipid rafts are cholesterol- and sphingolipid-enriched microdomains in cell membranes that regulate phosphorylation cascades originating from membrane-bound proteins. In this study, we tested whether alteration of the cholesterol content of lipid rafts in prostate cancer (PCa) cell membranes affects cell survival mechanisms in vitro and in vivo. Simvastatin, a cholesterol synthesis inhibitor, lowered raft cholesterol content, inhibited Akt1 serine-threonine kinase (protein kinase Balpha)/protein kinase B (Akt/PKB) pathway signaling, and induced apoptosis in caveolin- and PTEN-negative LNCaP PCa cells. Replenishing cell membranes with cholesterol reversed these inhibitory and apoptotic effects. Cholesterol also potentiated Akt activation in normal prostate epithelial cells, which were resistant to the apoptotic effects of simvastatin. Elevation of circulating cholesterol in SCID mice increased the cholesterol content and the extent of protein tyrosine phosphorylation in lipid rafts isolated from LNCaP/sHB xenograft tumors. Cholesterol elevation also promoted tumor growth, increased phosphorylation of Akt, and reduced apoptosis in the xenografts. Our results implicate membrane cholesterol in Akt signaling in both normal and malignant cells and provide evidence that PCa cells can become dependent on a cholesterol-regulated Akt pathway for cell survival.


Assuntos
Sobrevivência Celular , Colesterol/metabolismo , Microdomínios da Membrana/química , Neoplasias da Próstata/metabolismo , Transplante Heterólogo , Animais , Anticolesterolemiantes/farmacologia , Apoptose/fisiologia , Linhagem Celular Tumoral , Colesterol/química , Ativação Enzimática , Humanos , Masculino , Microdomínios da Membrana/efeitos dos fármacos , Microdomínios da Membrana/metabolismo , Camundongos , Camundongos SCID , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais/fisiologia , Sinvastatina/farmacologia
13.
Biochem Biophys Res Commun ; 311(2): 553-60, 2003 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-14592452

RESUMO

Little is known about mechanisms regulating gene expression for the alpha chains of basement membrane type IV collagen, arranged head-to-head in transcription units COL4A1-COL4A2, COL4A3-COL4A4, and COL4A5-COL4A6, and implicated broadly in genetic diseases. To investigate these mechanisms, we generated transgenic mouse lines bearing 5'-flanking sequences of COL4A5 and COL4A6, cloned upstream of a lacZ reporter gene. A 3.8-kb fragment upstream of COL4A6 directs reporter gene expression in the esophagus, stomach, and duodenum, whereas a 13.8-kb fragment directs expression in the esophagus only. A 10.6-kb fragment upstream of COL4A5 directs expression in the esophagus. Coupled with evidence of long-range conservation between human and mouse non-coding sequences, described herein, our findings provide the first indication that highly specialized patterns characteristic of COL4A5-COL4A6 expression in vivo arise from effects of distributed cis-acting regulatory elements on a bidirectional proximal promoter, itself transcriptionally competent.


Assuntos
Envelhecimento/fisiologia , Colágeno Tipo IV/biossíntese , Colágeno Tipo IV/genética , Regulação da Expressão Gênica/fisiologia , Ativação Transcricional/fisiologia , Trato Gastrointestinal Superior/crescimento & desenvolvimento , Trato Gastrointestinal Superior/metabolismo , Sequência de Aminoácidos , Animais , Colágeno Tipo IV/química , Colágeno Tipo IV/classificação , Genes Reguladores , Humanos , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Especificidade de Órgãos , Subunidades Proteicas/química , Homologia de Sequência , Especificidade da Espécie , Distribuição Tecidual , Trato Gastrointestinal Superior/citologia
14.
J Urol ; 169(3): 1165-70, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12576874

RESUMO

PURPOSE: Fibromuscular tissues of the detrusor/bladder body (B), trigone (T) and ureter (U) display distinct patterns of tissue remodeling in pathologic contexts, however the mechanisms underlying these observations are unknown. In this study we asked whether B, T and U smooth muscle cells (SMC) respond to several SMC growth factors and explored the role of caveolae/lipid raft membrane microdomains in signaling by one of these factors, PDGF-BB. MATERIALS AND METHODS: SMC were isolated and cultured from B, T and U from newborn rats and from human bladder detrusor. Responses to growth factors were assessed by cell proliferation, DNA synthesis, and immunoblot methods. Cholesterol was depleted from cell membranes in select experiments using cyclodextrin and the cholesterol synthesis inhibitor lovastatin. High-affinity PDGF receptor (PDGFR) sites were measured by 125I-PDGF-BB binding assay. RESULTS: PDGF-BB increased DNA synthesis rate in U and T SMC, with U SMC being highly responsive; in contrast, B SMC did not respond to this growth factor. Two other mitogens, HB-EGF and FGF-2, marginally stimulated DNA synthesis in all lineages. Human detrusor (hD) SMC were also highly responsive to PDGF-BB. Differences in responses to PDGF-BB correlated with translocation of PDGFRs into the caveolae/lipid raft membrane fraction following stimulation, but not with the number of high affinity PDGF binding sites. Cholesterol depletion from cell membranes reduced the response of U and hD SMC to PDGF-BB. CONCLUSIONS: These findings indicate that 1) PDGF-BB is likely to be a physiologically relevant stimulator of mitogenic signaling in certain types of urinary tract SMC, 2) there are significant and unanticipated regional differences in the ability of urinary tract SMC to respond to muscle mitogens, and 3) lipid raft membrane microdomains mediate, in part, the ability of urinary tract SMC to respond to PDGF-mediated signals.


Assuntos
Microdomínios da Membrana/metabolismo , Mitógenos/farmacologia , Músculo Liso/citologia , Fator de Crescimento Derivado de Plaquetas/fisiologia , Transdução de Sinais/fisiologia , Ureter/citologia , Bexiga Urinária/citologia , Animais , Animais Recém-Nascidos , Becaplermina , Divisão Celular , Células Cultivadas , Colesterol/metabolismo , Colesterol/fisiologia , DNA/biossíntese , Humanos , Immunoblotting , Microdomínios da Membrana/fisiologia , Músculo Liso/metabolismo , Fator de Crescimento Derivado de Plaquetas/farmacologia , Proteínas Proto-Oncogênicas c-sis , Ensaio Radioligante , Ratos , Ratos Long-Evans , Receptor alfa de Fator de Crescimento Derivado de Plaquetas/análise , Receptor beta de Fator de Crescimento Derivado de Plaquetas/análise , Ureter/metabolismo , Bexiga Urinária/metabolismo
15.
Lab Invest ; 82(12): 1755-64, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12480925

RESUMO

CaT1 is a highly selective calcium entry channel that has been proposed to be responsible for apical calcium entry in the vitamin D-regulated transcellular pathway of Ca(2+) absorption; however, the lack of a CaT1 antibody suitable for immunohistochemistry has prevented the direct testing of this hypothesis by the localization of CaT1 protein in the gastrointestinal tract and other tissues. In this study, we developed two CaT1 antibodies and have used them to establish for the first time that CaT1 localizes to the apical membrane of intestinal absorptive cells, thereby providing the first direct evidence that this protein is in fact an apical entry channel in the gastrointestinal tract. In addition, we found that CaT1 protein is highly expressed in a number of exocrine organs including pancreas, prostate, and mammary gland, suggesting an, as yet, unrecognized role in secretory epithelia. Finally, we found CaT1 protein to be present at elevated levels in comparison with normal tissues in a series of prostate, breast, thyroid, colon, and ovarian carcinomas, consistent with previous reports of up-regulation of CaT1 mRNA in prostate cancer tissues. Our findings indicate that CaT1 is likely to serve as a component of transcellular calcium transport mechanisms in many tissues and epithelial cancers.


Assuntos
Canais de Cálcio/metabolismo , Mucosa Intestinal/metabolismo , Neoplasias/metabolismo , Sequência de Aminoácidos , Animais , Canais de Cálcio/genética , Canais de Cálcio/imunologia , Células Cultivadas , Glândulas Exócrinas/metabolismo , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Técnicas Imunoenzimáticas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , RNA Mensageiro/genética , Análise de Sequência de Proteína , Canais de Cátion TRPV , Transfecção
16.
Endocrinology ; 143(12): 4599-608, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12446587

RESUMO

Peptide growth factors have been implicated in progression of prostate cancer (PCa) to the androgen-independent state; however, much of the evidence linking diffusible mitogens and survival factors to this process remains circumstantial. Heparin-binding epidermal growth factor-like growth factor (HB-EGF), a prostate stroma-derived factor, promotes survival, proliferation, and neuroendocrine differentiation of androgen-dependent LNCaP PCa cells in vitro. To test whether sustained exposure to HB-EGF can confer an androgen-independent phenotype, we generated stable populations of LNCaP cells that express constitutively a secreted form of HB-EGF (LNCaP/sHB). LNCaP/sHB cells proliferated more rapidly under androgen-depleted conditions in vitro and formed larger tumors with higher frequency in intact and castrated severe combined immunodeficient mice, in comparison to control cells. LNCaP/sHB tumors also expressed higher levels of the neuroendocrine marker, neuron-specific enolase, compared with control tumors. In castrates, increased neuron-specific enolase expression in LNCaP/sHB tumors was associated with reduced androgen receptor (AR) levels. In vitro, AR protein levels were reduced in LNCaP/sHB cells, and in transient transfection assays using an androgen-responsive promoter (mouse mammary tumor virus-long terminal repeat), LNCaP/sHB cells showed reduced sensitivity to dihydrotestosterone compared with controls. This is the first demonstration that continuous exposure of AR-positive PCa cells to a single growth factor can promote an androgen-independent phenotype in vivo. These findings also emphasize the potential role of pathways other than the AR axis in acquisition of androgen independence.


Assuntos
Antagonistas de Receptores de Andrógenos , Androgênios/farmacologia , Fator de Crescimento Epidérmico/fisiologia , Neoplasias da Próstata/patologia , Animais , Divisão Celular , Meios de Cultivo Condicionados , Di-Hidrotestosterona/farmacologia , Fator de Crescimento Epidérmico/genética , Expressão Gênica , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Immunoblotting , Peptídeos e Proteínas de Sinalização Intercelular , Masculino , Camundongos , Camundongos SCID , Transplante de Neoplasias , Fosfopiruvato Hidratase/análise , Receptores Androgênicos/análise , Solubilidade , Transfecção , Células Tumorais Cultivadas
17.
Cancer Res ; 62(8): 2227-31, 2002 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-11956073

RESUMO

Although cholesterol accumulation in tumors was first reported in the early20th century, the mechanistic implications of this observation are still obscure. Here we report that caveolin-negative human prostate cancer (LNCaP) cells contain cholesterol-rich lipid rafts that mediate epidermal growth factor (EGF)-induced and constitutive signaling through the Akt1 serine-threonine kinase. EGF receptor and Akt1 phosphorylation were inhibited and autonomous cell survival was reduced when the rafts were disrupted. Reconstitution of the rafts with cholesterol restored EGF receptor-->Akt1 axis signaling and cytoprotection from a phosphoinositide 3-kinase-dependent apoptotic signal. These results suggest that cholesterol present in membrane microdomains is a prominent mediator of survival in prostate cancer cells.


Assuntos
Colesterol/fisiologia , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/fisiologia , Membrana Celular/metabolismo , Sobrevivência Celular/fisiologia , Colesterol/metabolismo , Fator de Crescimento Epidérmico/farmacologia , Receptores ErbB/fisiologia , Humanos , Masculino , Lipídeos de Membrana/metabolismo , Lipídeos de Membrana/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/fisiologia , Neoplasias da Próstata/enzimologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-akt , Proteínas Recombinantes/farmacologia , Transdução de Sinais/fisiologia
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