RESUMO
BACKGROUND: Typically, researchers and clinicians determine the agenda in sarcoma research. However, patient involvement can have a meaningful impact on research. Therefore, the Patient-Powered Research Network (PPRN) of the Sarcoma Patient Advocacy Global Network (SPAGN) set up a Priority Setting Partnership (PSP). The primary objective of this partnership is to identify priorities for research and patient advocacy topics. METHODS: In the first phase of this PSP, including 264 sarcoma patients and carers from all over the world, 23 research topics regarding sarcomas and 15 patient advocacy topics were identified using an online survey. In the second phase, participants were asked to fill in a top five and a top three of research and patient advocacy topics, respectively. Additionally, sociodemographic characteristics and sarcoma characteristics were collected. Social media channels, local national patient advocacy groups and the SPAGN website were used to distribute the survey. RESULTS: In total, 671 patients (75%) and carers (25%) participated in this survey. The five highest ranked research topics were related to causes of sarcoma (43%), prognosis and risk of recurrence (40%), specific subtypes of sarcoma (33%), the role of immunotherapy, targeted therapy and combined therapy (30%), and hereditary aspects (30%). The three highest ranked patient advocacy topics were improving the diagnostic process of sarcoma (39%), access to tumor DNA analysis (37%) and establishing an international sarcoma registry (37%). CONCLUSIONS: This sarcoma PSP has identified priorities for research and patient advocacy, offering guidance for researchers, assisting funding agencies with assessing project relevance and empowering patient advocates to represent the needs of patients and carers.
Assuntos
Cuidadores , Defesa do Paciente , Sarcoma , Humanos , Sarcoma/terapia , Feminino , Masculino , Cuidadores/psicologia , Pessoa de Meia-Idade , Adulto , Inquéritos e Questionários , Pesquisa Biomédica , Idoso , Participação do Paciente , Adulto JovemRESUMO
BACKGROUND: Research in sarcomas has historically been the domain of scientists and clinicians attempting to understand the disease to develop effective treatments. This traditional approach of placing scientific rigor before the patient's reality is changing. This evolution is reflected in the growth of patient-centered organizations and patient advocacy groups that seek to meaningfully integrate patients into the research process. The aims of this study are to identify the unanswered questions regarding sarcomas (including gastrointestinal stromal tumors and desmoid fibromatosis) from patient, carer, and clinical perspectives and examine how patients and carers want to be involved in sarcoma research. METHODS: The Patient-Powered Research Network of Sarcoma Patients EuroNet set up a Priority Setting Partnership (PSP) in collaboration with stakeholders from the sarcoma research field. This PSP is largely based on the James Lind Alliance methodology. RESULTS: In total, 264 sarcoma patients (73%) and carers (27%) from all over the world participated in the online survey and covered the full spectrum of sarcomas. The topics mentioned were labeled in accordance with the Common Scientific Outline of the International Cancer Research Partnership and lists for potential research topics, advocacy topics, and requests for information were constructed. With regard to patient and carer involvement, 64% were very willing to be actively involved and mainly in the following areas: sharing perspectives, discussing patient-clinician interactions, and attending research meetings. CONCLUSIONS: The first results of this sarcoma PSP identified important research questions, but also important topics for patient advocacy groups and further improvement of information materials. Sarcoma patients and carers have a strong wish to be involved in multiple aspects of sarcoma research. The next phase will identify the top 10 research priorities per tumor type. These priorities will provide guidance for research that will achieve greatest value and impact.
Assuntos
Cuidadores , Sarcoma , Humanos , Sarcoma/terapia , Inquéritos e Questionários , Resultado do TratamentoRESUMO
A case of a patient suffering from COVID-19 with suspected associated myositis is reported, in which the initially limited information about the history and disease course led to difficulties in establishing a reasonable diagnosis. Through inquiry, further data could be collected, so that the diagnosis of an infection-associated thrombotic microangiopathy in the context of a Morganella morganii myositis could be made. This patient study shows that even in times of the omnipresent pandemic and despite the context of a positive COVID-19 test result, differential diagnoses and the integrative clinicopathologic approach in interpreting muscle biopsy findings should not be neglected.
Assuntos
COVID-19 , Miosite , Biópsia , Progressão da Doença , Humanos , Músculos/patologia , Miosite/diagnóstico , PandemiasRESUMO
OBJECTIVE: Retroperitoneal sarcomas (RPSs) are rare cancers with some variability in clinical and histopathological presentation. In Germany, general treatment strategies of retroperitoneal sarcoma are unknown since centralized registries do not exist. The objective of this survey was to access the medical care of RPS patients in Germany. METHODS: In cooperation with the German Society of General and Visceral surgery, the German Interdisciplinary Sarcoma Study Group and the patient advocacy group Das Lebenshaus we designed an online survey assessing diagnostic and treatment strategies (e. g. performance of tumor biopsies, administration of multimodal therapies and surgical strategy). All departments for general and visceral surgery in Germany were addressed (n = 976). RESULTS: Responses were received from 191 of 976 departments. Only 11 surgical departments treat more than 10 RPS patients per year. A multidisciplinary sarcoma board exists in 19 hospitals. Staging is generally performed by cross-sectional imaging. In 54% of the departments pretreatment tumor biopsy is a standard procedure. Surgery is performed as compartment resection in 85% of the departments. A systematic lymph node dissection is done in 40%. Adjuvant radio- or chemotherapy is performed as a standard treatment in 27% and 22% departments, respectively. CONCLUSION: The survey demonstrates a large heterogeneity in RPS diagnostic and treatment strategies. Dedicated education programs and centralized treatment strategies are warranted to improve the standard of care.
Assuntos
Neoplasias Retroperitoneais , Sarcoma , Alemanha , Humanos , Neoplasias Retroperitoneais/cirurgia , Sarcoma/cirurgia , Inquéritos e QuestionáriosRESUMO
The inadequate transport of drugs into the tumor tissue caused by its abnormal vasculature is a major obstacle to the treatment of cancer. Anti-vascular endothelial growth factor (anti-VEGF) drugs can cause phenotypic alteration and maturation of the tumor's vasculature. However, whether this consistently improves delivery and subsequent response to therapy is still controversial. Clinical results indicate that not all patients benefit from antiangiogenic treatment, necessitating the development of criteria to predict the effect of these agents in individual tumors. We demonstrate that, in anti-VEGF-refractory murine tumors, vascular changes after VEGF ablation result in reduced delivery leading to therapeutic failure. In these tumors, the impaired response after anti-VEGF treatment is directly linked to strong deposition of fibrillar extracellular matrix (ECM) components and high expression of lysyl oxidases. The resulting condensed, highly crosslinked ECM impeded drug permeation, protecting tumor cells from exposure to small-molecule drugs. The reduced vascular density after anti-VEGF treatment further decreased delivery in these tumors, an effect not compensated by the improved vessel quality. Pharmacological inhibition of lysyl oxidases improved drug delivery in various tumor models and reversed the negative effect of VEGF ablation on drug delivery and therapeutic response in anti-VEGF-resistant tumors. In conclusion, the vascular changes after anti-VEGF therapy can have a context-dependent negative impact on overall therapeutic efficacy. A determining factor is the tumor ECM, which strongly influences the effect of anti-VEGF therapy. Our results reveal the prospect to revert a possible negative effect and to potentiate responsiveness to antiangiogenic therapy by concomitantly targeting ECM-modifying enzymes.
Assuntos
Anticorpos Monoclonais/farmacologia , Matriz Extracelular/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Camundongos , Modelos Biológicos , Terapia de Alvo Molecular , Neoplasias/tratamento farmacológico , Permeabilidade , Proteína-Lisina 6-Oxidase/metabolismo , Sarcoma/tratamento farmacológico , Sarcoma/metabolismo , Sarcoma/patologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Approximately 15% of follicular lymphomas (FLs) lack breaks in the BCL2 locus. The aim of this study was to better define molecular and clinical features of BCL2-breakpoint/t(14;18)-negative FLs. We studied the presence of BCL2, BCL6 and MYC breaks by fluorescence in situ hybridization and the expression of BCL2, MUM1, CD10, P53 and Ki67 in large clinical trial cohorts of 540 advanced-stage FL cases and 116 early-stage disease FL patients treated with chemotherapy regimens and radiation, respectively. A total of 86% and 53% of advanced- and early-stage FLs were BCL2-breakpoint-positive, respectively. BCL2 was expressed in almost all FLs with BCL2 break and also in 86% and 69% of BCL2-breakpoint-negative advanced- and early-stage FLs, respectively. CD10 expression was significantly reduced in BCL2-breakpoint-negative FLs of all stages and MUM1 and Ki67 expression were significantly increased in BCL2-break-negative early-stage FLs. Patient characteristics did not differ between FLs with and without BCL2 breaks and neither did survival times in advanced-stage FLs. These results suggest that the molecular profile differs to some extent between FLs with and without BCL2 breaks and support the notion that FLs with and without BCL2 breaks belong to the same lymphoma entity.
Assuntos
Quebra Cromossômica , Regulação Neoplásica da Expressão Gênica , Linfoma Folicular/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 18/genética , Estudos de Coortes , Feminino , Seguimentos , Humanos , Linfoma Folicular/genética , Linfoma Folicular/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Prognóstico , Taxa de Sobrevida , Translocação Genética/genéticaRESUMO
BACKGROUND: There is evidence that tumour-stroma interactions have a major role in the neoplastic progression of pancreatic ductal adenocarcinoma (PDAC). Tumour budding is thought to reflect the process of epithelial-mesenchymal transition (EMT); however, the relationship between tumour buds and EMT remains unclear. Here we characterize the tumour-budding- and stromal cells in PDAC at protein and mRNA levels concerning factors involved in EMT. METHODS: mRNA in situ hybridisation and immunostaining for E-cadherin, ß-catenin, SNAIL1, ZEB1, ZEB2, N-cadherin and TWIST1 were assessed in the main tumour, tumour buds and tumour stroma on multipunch tissue microarrays from 120 well-characterised PDACs and associated with the clinicopathological features, including peritumoural (PTB) and intratumoural (ITB) budding. RESULTS: Tumour-budding cells showed increased levels of ZEB1 (P<0.0001) and ZEB2 (P=0.0119) and reduced E-cadherin and ß-catenin (P<0.0001, each) compared with the main tumour. Loss of membranous ß-catenin in the main tumour (P=0.0009) and tumour buds (P=0.0053), without nuclear translocation, as well as increased SNAIL1 in tumour and stromal cells (P=0.0002, each) correlated with high PTB. ZEB1 overexpression in the main tumour-budding and stromal cells was associated with high ITB (P=0.0084; 0.0250 and 0.0029, respectively) and high PTB (P=0.0005; 0.0392 and 0.0007, respectively). ZEB2 overexpression in stromal cells correlated with higher pT stage (P=0.03), lymphatic invasion (P=0.0172) and lymph node metastasis (P=0.0152). CONCLUSIONS: In the tumour microenvironment of phenotypically aggressive PDAC, tumour-budding cells express EMT hallmarks at protein and mRNA levels underlining their EMT-type character and are surrounded by stromal cells expressing high levels of the E-cadherin repressors ZEB1, ZEB2 and SNAIL1, this being strongly associated with the tumour-budding phenotype. Moreover, our findings suggest the existence of subtypes of stromal cells in PDAC with phenotypical and functional heterogeneity.
Assuntos
Carcinoma Ductal Pancreático/patologia , Proteínas de Homeodomínio/biossíntese , Neoplasias Pancreáticas/patologia , RNA Mensageiro/metabolismo , Proteínas Repressoras/biossíntese , Células Estromais/patologia , Fatores de Transcrição/biossíntese , Caderinas/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Transição Epitelial-Mesenquimal , Proteínas de Homeodomínio/genética , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fenótipo , RNA Mensageiro/genética , Proteínas Repressoras/genética , Fatores de Transcrição da Família Snail , Fatores de Transcrição/genética , Microambiente Tumoral , Homeobox 2 de Ligação a E-box com Dedos de Zinco , Homeobox 1 de Ligação a E-box em Dedo de ZincoRESUMO
Prognostically relevant risk factors in patients with diffuse large B-cell lymphoma (DLBCL) have predominantly been evaluated in elderly populations. We tested whether previously described risk factors are also valid in younger, poor-prognosis DLBCL patients. Paraffin-embedded samples from 112 patients with de novo DLBCL, enrolled in the R-MegaCHOEP trial of the German High Grade Non-Hodgkin Lymphoma Study Group (DSHNHL) were investigated using immunohistochemistry (MYC, FOXP1, LMO2, GCET1, CD5, CD10, BCL2, BCL6, IRF4/MUM1) and fluorescence in situ hybridization (MYC, BCL2, BCL6). MYC, BCL2 and BCL6 breaks occurred in 14, 21 and 31%, respectively. In the majority of cases, MYC was simultaneously rearranged with BCL2 and/or BCL6. The adverse impact of MYC rearrangements was confirmed, but the sole presence of BCL2 breaks emerged as a novel prognostic marker associated with inferior overall survival (OS) (P=0.002). Combined overexpression of MYC and BCL2 showed only limited association with inferior OS. All immunohistochemical cell of origin classifiers applied failed to predict survival time. DLBCL tumors with significant proportion of immunoblastic and/or immunoblastic-plasmacytoid cells had inferior OS, independently from from BCL2 break. Younger, poor-prognosis DLBCL patients, therefore, display different biological risk factors compared with an elderly population, with BCL2 translocations emerging as a powerful negative prognostic marker.
Assuntos
Biomarcadores Tumorais/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Adolescente , Adulto , Biomarcadores Tumorais/genética , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Risco , Taxa de Sobrevida , Adulto JovemRESUMO
Spontaneous rupture of hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolization (TACE) is a rare and life-threatening complication. Pathophysiologic mechanisms are not yet fully known; it is suggested that rupture is preceded by reactive tissue edema and intratumerous bleeding, leading to a rapid expansion of tumour mass with risk of extrahepatic bleeding in the case of subcapsular localisation. This case report discusses a sudden, unexpected lethal complication in a 74 year-old male patient treated with TACE using DC Bead loaded with doxorubicin (DEBDOX) in a progressive multifocal HCC.
Assuntos
Carcinoma Hepatocelular/terapia , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/terapia , Idoso , Angiografia , Meios de Contraste/administração & dosagem , Evolução Fatal , Humanos , Iopamidol/administração & dosagem , Iopamidol/análogos & derivados , Masculino , Microesferas , Ruptura Espontânea , Tomografia Computadorizada por Raios XRESUMO
Major research initiatives in antiangiogenesis research have been undertaken to control angiogenic diseases such as polyarthritis, psoriasis, endometriosis, and diabetic retinopathy, and inhibition of tumor-induced angiogenesis has emerged as one of the most promising anti-cancer therapies currently available. Although several quantitative in vivo (i.e., animal models) as well as in vitro (i.e., pure endothelial cell cultures) angiogenesis assays have been described, the development of novel angiogenesis assays with organotypic culture systems that take into account oxygen and nutrient gradients, depth-dependent changes in intracellular pH and a redox state similar to that found in a natural tissue microenvironment are necessary to investigate blood vessel growth. Embryonic stem cells of mouse and human origin have the capacity to develop into three-dimensional tissues with functional capillaries, and this model system represents an excellent in vitro model for antiangiogenesis research. Upon confrontation of stem cells by co-culture with multicellular tumor spheroids, tumor-induced angiogenesis, i.e., the invasion of endothelial host-derived cells into a tumor tissue, can also be monitored. The current review provides an overview of embryonic stem cells as novel tools for antiangiogenesis research and outlines the use of confrontation cultures for the study of tumor-induced angiogenesis.
Assuntos
Inibidores da Angiogênese/farmacologia , Pesquisa Biomédica/métodos , Neoplasias/irrigação sanguínea , Neovascularização Patológica , Células-Tronco/metabolismo , Animais , Humanos , Neoplasias/tratamento farmacológico , Criação de Embriões para Pesquisa , Células-Tronco/citologia , Células-Tronco/efeitos dos fármacosRESUMO
Active Ca2+ transport in living cells necessitates controlled supply of metabolic energy. Direct coupling between sarco/endoplasmic reticulum (ER) Ca2+ ATPases (SERCA) and intracellular energy-generation sites has been well established experimentally. On the basis of these experimental findings we propose a pump-driven model to investigate complex dynamic properties of a cell system. The model describes the pump process both by the Ca2+ ATPase itself and by a suitable description of the glycolysis. The associated set of differential equations shows a rich behavior, the solutions ranging from simple periodic oscillations to complex patterns such as bursting and spiking. Recent experimental results on calcium oscillations in Xenopus laevis oocytes and on dynamic patterns of intracellular Ca2+ concentrations in electrically non-excitable cells are well described by corresponding theoretical results derived within the proposed model. The simulation results are further compared to spontaneous [Ca2+] oscillations in primitive endodermal cells.
Assuntos
Cálcio/metabolismo , Células/metabolismo , Retículo Endoplasmático/metabolismo , Animais , Transporte Biológico , ATPases Transportadoras de Cálcio/metabolismo , Cátions , Citosol/metabolismo , Células Endoteliais/metabolismo , Feminino , Glicólise , Modelos Biológicos , Oócitos/metabolismo , Xenopus laevisRESUMO
This paper examines and compares necrosis in human ovarian tissue after conventional slow freezing or vitrification and ensuing xenotranplantation. Slow cryoconserved or vitrified ovarian tissue samples and fresh controls from nine patients were subcutaneously transplanted into SCID mice. The tissue samples were explanted after 6 weeks and the necrotic areas were examined by staining with Lucifer yellow SV. The size of the necrotic areas in parallel cultivated ovarian tissue samples was compared, as was necrosis in cultivated prostate tumour spheroids where the emergence of necrosis and its pathophysiological correlation have been described. Examinations showed no significant rise in the proportion of necrotic areas after slow cryoconservation/transplantation and in the controls (transplanted fresh tissue, not transplanted fresh tissue, long-term culture). The proportion of necrotic areas in the tumour spheroids was significantly higher than in the ovarian tissue. Vitrification could, after these results, be presented as an alternative to conventional slow cryoconservation.
Assuntos
Criopreservação/métodos , Necrose , Transplante de Órgãos/métodos , Ovário/patologia , Adulto , Animais , Linhagem Celular Tumoral , Feminino , Corantes Fluorescentes/farmacologia , Congelamento , Humanos , Isoquinolinas/farmacologia , Masculino , Camundongos , Camundongos SCID , Compostos Orgânicos , Neoplasias da Próstata/patologia , Fatores de Tempo , Transplante HeterólogoRESUMO
Replacement of damaged myocardium with electrically functional, contracting syncytium with a balanced blood supply remains a key goal for the treatment of hearts damaged by coronary heart disease or other disorders. Stem cell therapy offers a potential solution. This paper describes the value of in vitro stem cell research to unravel the roles of key regulatory molecules in embryogenesis of myocardium and blood vessels. Studies have shown that functioning myocytes can be derived from stem cells in vitro and engrafted into infarcted areas of heart where they develop into functional adult like cardiomyocytes with action potentials and capacity for beta adrenergic and muscarinic regulation. Further studies have identified specific roles for platelet endothelial cell adhesion molecule (PECAM), vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF) in the sequential differentiation of blood vessels and capillaries.
Assuntos
Infarto do Miocárdio/terapia , Miócitos Cardíacos/transplante , Transplante de Células-Tronco/métodos , Animais , Diferenciação Celular/fisiologia , Clonagem Molecular , Humanos , CamundongosRESUMO
Mitogenic stimulation by growth factors may be mediated through intracellular reactive oxygen species (ROS) acting as signaling molecules. Incubation of multicellular prostate tumor spheroids with adenosine 5' triphosphate (ATP) dose-dependently stimulated tumor growth. ATP, uridine 5'-triphosphate (UTP), adenosine 5'-diphosphate (ADP), and 2-methylthio-ATP (2-MeS-ATP) increased intracellular ROS levels significantly. ROS generation by ATP was inhibited by the P2 receptor antagonist suramin, by the reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitors diphenylene iodonium chloride (DPI) and 4-(2-aminoethyl) benzenesulfonylfluoride (AEBSF), as well as by the Ca2+-dependent phospholipase A2 (PLA2) inhibitors indomethacin and methyl arachidonyl fluorophosphonate (MAFP). The generation of ROS was dependent on the intracellular Ca2+ response evoked by ATP. Exogenous ATP activated the extracellular signal-regulated kinase 1/2 (ERK1/2) mitogen-activated protein kinase (MAPK) pathway, which was blunted by the MAPK/ERK kinase 1/2 (MEK1/2) antagonist PD98059. The radical scavengers vitamin E, dimethyl thiourea (DMTU), and N-acetyl cysteine (NAC) failed to inhibit ERK1/2 activation but abolished p90 ribosomal S6 kinase (p90RSK) activation downstream of ERK1/2, as well as the growth stimulation of tumor spheroids. Our data indicate that p90RSK downstream of ERK1/2 is the molecular target for ROS generated through stimulation of purinergic receptors by ATP.
Assuntos
Trifosfato de Adenosina/farmacologia , Agonistas Purinérgicos , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases S6 Ribossômicas/efeitos dos fármacos , Esferoides Celulares/efeitos dos fármacos , Tioureia/análogos & derivados , Acetilcisteína/farmacologia , Cálcio/farmacologia , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Flavonoides/farmacologia , Sequestradores de Radicais Livres/farmacologia , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , NADPH Oxidases/metabolismo , Fosfolipases A/metabolismo , Fosfolipases A2 , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores Purinérgicos/fisiologia , Proteínas Quinases S6 Ribossômicas/metabolismo , Esferoides Celulares/metabolismo , Esferoides Celulares/patologia , Tioureia/farmacologia , Células Tumorais Cultivadas , Vitamina E/farmacologiaRESUMO
At present, the long-term culture of ovarian tissue is problematic. The aim of this study was to measure apoptosis in long-term cultures of human ovarian tissue. Biopsies of human ovaries were cultured for 6 weeks. Samples were taken weekly for histological investigation. The apoptotic cells were marked with anti-caspase 3. Simultaneous to this experiment, other tissue samples were preincubated for 3 h with 1 micromol staurosporine l(-1), an inducer of apoptosis, and apoptosis was compared among samples. Furthermore, the proportion of lethal cells was determined weekly. After 6 weeks, 99% of the tissue samples showed an intact structure. They expanded in all directions on the floor of the multi-wells to form a monolayer. Apoptotic cells could be marked only sporadically (16.3 +/- 5.9 fluorescence (counts per 3600 microm(2))) after 6 weeks. After preincubation with staurosporine after the same period of culture, the proportion of apoptotic cells was significantly increased compared with that in untreated control samples (66.8 +/- 14.5 versus 16.3 +/- 5.9%, respectively; P < 0.05). Under the same experimental conditions, the proportion of lethal cells was 3.6 +/- 0.9, 3.9 +/- 2.1 and 5.2 +/- 1.5% for weeks 1, 3 and 6, respectively. After preincubation with 1 micromol staurosporine l(-1), the proportion of pyknotic cells after 6 weeks of culture was significantly higher (37.2 +/- 4.4%) than that in control samples (3.95 +/- 2.05%; P < 0.05). No significant increase in apoptosis in cultured human ovarian tissue after 6 weeks was observed compared with control tissues on day 1. These results indicate that under optimal culture conditions it is possible to cultivate human ovarian tissue long term. The influence of long-term culture on hormone synthesis and follicle maturity will be investigated further.
Assuntos
Apoptose , Técnicas de Cultura , Ovário/fisiologia , Adulto , Caspase 3 , Caspases/análise , Inibidores Enzimáticos/farmacologia , Feminino , Humanos , Imuno-Histoquímica , Microscopia Confocal , Estaurosporina/farmacologia , Fatores de TempoRESUMO
Reactive oxygen species (ROS) are generated following ligand-receptor interactions and function as specific second messengers in signaling cascades involved in cell proliferation and differentiation. Although ROS are generated intracellularly by several sources, including mitochondria, the primary sources of ROS involved in receptor-mediated signaling cascades are plasma membrane oxidases, preferentially NADPH oxidases, with a rapid kinetics of activation and inactivation. This allows a tight up- and downregulation of intracellular ROS levels within the short time required for the transduction of signals from the plasma membrane to the cell nucleus. The mode of action of ROS may involve direct interaction with specific receptors, and/or redox-activation of members of signaling pathways such as protein kinases, protein phosphatases, and transcription factors. Furthermore, ROS act in concert with intracellular Ca(2+) in signaling pathways which regulate the balance of cell proliferation versus cell cycle arrest and cell death. The delicate intracellular interplay between oxidizing and reducing equivalents allows ROS to function as second messengers in the control of cell proliferation and differentiation.