RESUMO
In addition to clinical staging, a number of biomarkers predicting overall survival (OS) have been identified in chronic lymphocytic leukemia (CLL). The multiplicity of markers, limited information on their independent prognostic value, and a lack of understanding of how to interpret discordant markers are major barriers to use in routine clinical practice. We therefore performed an analysis of 23 prognostic markers based on prospectively collected data from 1948 CLL patients participating in phase 3 trials of the German CLL Study Group to develop a comprehensive prognostic index. A multivariable Cox regression model identified 8 independent predictors of OS: sex, age, ECOG status, del(17p), del(11q), IGHV mutation status, serum ß2-microglobulin, and serum thymidine kinase. Using a weighted grading system, a prognostic index was derived that separated 4 risk categories with 5-year OS ranging from 18.7% to 95.2% and having a C-statistic of 0.75. The index stratified OS within all analyzed subgroups, including all Rai/Binet stages. The validity of the index was externally confirmed in a series of 676 newly diagnosed CLL patients from Mayo Clinic. Using this multistep process including external validation, we developed a comprehensive prognostic index with high discriminatory power and prognostic significance on the individual patient level. The studies were registered as follows: CLL1 trial (NCT00262782, http://clinicaltrials.gov), CLL4 trial (ISRCTN 75653261, http://www.controlled-trials.com), and CLL8 trial (NCT00281918, http://clinicaltrials.gov).
Assuntos
Biomarcadores Tumorais/análise , Leucemia Linfocítica Crônica de Células B/classificação , Leucemia Linfocítica Crônica de Células B/diagnóstico , Leucemia Linfocítica Crônica de Células B/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos Fase III como Assunto , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
We investigated the role of transforming growth factor-beta activated kinase 1 (TAK1) in collagen II signaling in primary human chondrocytes (PHCs). We asked whether TAK1 acts as a modulator of collagen II signaling with respect to collagen-II-dependent induction of cyclooxigenase-2 (COX-2) in PHCs and release of PGE2 from PHCs. Therefore, PHCs were incubated with collagen II, and cells were then analyzed by RT-PCR for the expression of COX-2. ELISA was used to quantify PGE2 release. To examine the influence of TAK1 on these events, TAK1 gene silencing was performed by RNAi in PHCs prior to collagen II treatment. Results indicated that COX-2 gene expression and PGE2 release are specific outcomes of collagen II signaling and that both depend on TAK1 mediation. These findings are promising in that therapeutic inhibition of TAK1 might be used to reduce pain and relieve inflammatory symptoms that are common in osteoarthritis.
Assuntos
Condrócitos/enzimologia , Condrócitos/metabolismo , Colágeno Tipo II/fisiologia , Ciclo-Oxigenase 2/biossíntese , Dinoprostona/metabolismo , Regulação da Expressão Gênica/fisiologia , MAP Quinase Quinase Quinases/fisiologia , Cartilagem Articular/citologia , Cartilagem Articular/metabolismo , Cartilagem Articular/patologia , Células Cultivadas , Ciclo-Oxigenase 2/genética , Inativação Gênica/fisiologia , Humanos , Osteoartrite/genética , Osteoartrite/metabolismo , Osteoartrite/patologiaRESUMO
OBJECTIVES: Low-T3 syndrome is highly prevalent and independently prognostic in cardiovascular patients. The relationship and prognostic impact with the cardiac marker NT-pro-BNP have not been thoroughly investigated. METHODS: Thyroid hormone levels and NT-pro-BNP were assessed in 615 consecutive patients hospitalized for cardiovascular disease. Patients with primary overt or latent thyroid disorder, hormone replacement, thyreostatic and amiodarone therapy were excluded. The association with and predictive impact on mortality were examined. RESULTS: 36 (7.1%) patients had low-T3 syndrome. After adjustment for known confounders, NT-pro-BNP was significantly associated with fT3 and low-T3 syndrome. fT3 (HR 0.58, 95%CI 0.34-0.98) and low-T3 syndrome (HR 3.0, 95%CI 1.4-6.3) were predictive for mortality after adjustment for NT-pro-BNP levels and other cardiovascular prognostic variables. In patients with fT3 levels within the normal range, fT3 and NT-pro-BNP stratified by median values showed complementary prognostic information with the highest risk for mortality in patients with low normal fT3 and high NT-pro-BNP (HR 10.5, 95%CI 3.2-34.6). CONCLUSIONS: fT3 and low-T3 syndrome are significantly related to NT-pro-BNP in patients with cardiovascular disease, but are predictors of mortality independently of NT-pro-BNP and other known cardiovascular risk parameters.
Assuntos
Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/complicações , Síndromes do Eutireóideo Doente/sangue , Síndromes do Eutireóideo Doente/complicações , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Idoso , Doenças Cardiovasculares/mortalidade , Síndromes do Eutireóideo Doente/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Hormônios Tireóideos/sangueRESUMO
Here, we tested the matrilin-3-dependent induction of osteoarthritis-associated genes in primary human chondrocytes. Matrilin stimulation leads to the induction of MMP1, MMP3, MMP13, COX-2, iNOS, IL-1beta, TNFalpha, IL-6 and IL-8. Furthermore, we show the participation of ADAMTS4 and ADAMTS5 in the in vitro degradation of matrilin-3. We provide evidence for a matrilin-3-dependent feed-forward mechanism of matrix degradation, whereby proteolytically-released matrilin-3 induces pro-inflammatory cytokines as well as ADAMTS4 and -5 indirectly via IL-1beta. ADAMTS4 and ADAMTS5, in turn, cleave matrilin-3 and may release more matrilin-3 from the matrix, which could lead to further release of pro-inflammatory cytokines and proteases in cartilage.
Assuntos
Condrócitos/efeitos dos fármacos , Proteínas da Matriz Extracelular/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoartrite/genética , Proteínas ADAM/metabolismo , Proteína ADAMTS4 , Proteína ADAMTS5 , Células Cultivadas , Condrócitos/citologia , Condrócitos/metabolismo , Ciclo-Oxigenase 2/genética , Ensaio de Imunoadsorção Enzimática , Proteínas da Matriz Extracelular/genética , Humanos , Immunoblotting , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-8/metabolismo , Proteínas Matrilinas , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 3 da Matriz/genética , Óxido Nítrico Sintase Tipo II/genética , Pró-Colágeno N-Endopeptidase/metabolismo , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Necrose Tumoral alfa/metabolismoRESUMO
We deciphered constituent parts of a signal transduction cascade that is initiated by collagen II and results in the release of various pro-inflammatory cytokines, including interleukin-6 (IL-6), in primary human chondrocytes. This cascade represents a feed-forward mechanism whereby cartilage matrix degradation is exacerbated by the mutually inducing effect of released collagen II fragments and pro-inflammatory cytokines. We previously proposed discoidin domain receptor 2 as a central mediator in this event. Since this cascade plays a prominent role in the pathogenesis of osteoarthritis, our study further investigates the hypothesis that discoidin domain receptor 2 is a candidate receptor for collagen II, and that transcription factor NFkappaB, lipid kinase PI3K, and the MAP kinases are constituent parts of this very signal transduction cascade. To accomplish this, we selectively knocked down the molecules of interest in primary human chondrocytes, induced the specified cascade by incubating primary human chondrocytes with collagen II, and observed the outcome, specifically the changes in interleukin-6 release. Knockdown was performed by siRNA-mediated gene silencing in the case of discoidin domain receptor 2 (DDR2) or by using specific inhibitors for the remainder of the molecules. Results indicated that discoidin domain receptor 2 mediates the collagen II-dependent release of interleukin-6 in primary human chondrocytes and that MAP kinases p38, JNK and ERK, as well as transcription factor NFkappaB, are integral components of intracellular collagen II signalling. Given the detrimental role of these molecules in osteoarthritis, our findings provide new targets for more specific therapeutics, which may have fewer side effects than those currently applied.
Assuntos
Condrócitos/metabolismo , Interleucina-6/metabolismo , Osteoartrite do Joelho/metabolismo , Receptores Proteína Tirosina Quinases/metabolismo , Receptores Mitogênicos/metabolismo , Transdução de Sinais/fisiologia , Análise de Variância , Células Cultivadas , Colágeno Tipo II/farmacologia , Receptores com Domínio Discoidina , Inibidores Enzimáticos/farmacologia , MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Immunoblotting , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Articulação do Joelho , NF-kappa B/metabolismo , Interferência de RNA , RNA Interferente Pequeno/farmacologia , Receptores Proteína Tirosina Quinases/genética , Receptores Mitogênicos/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismoRESUMO
We report a process that results in the acceleration of matrix degradation in human articular cartilage, a phenomenon commonly observed in osteoarthritis (OA). The study was conducted by (1) examining the potential of collagen II in modulating the gene expression profile of primary human chondrocytes (PHCs), and (2) investigating the involvement of pro-inflammatory signaling cascades. We first tested the collagen II-dependent induction of pro-inflammatory cytokines and matrix metalloproteinases (MMPs) in PHCs. PHCs were incubated with or without monomeric (i.e., nonfibrillar) collagen II. Cells were then analyzed by RT-PCR for the expression of MMP1, MMP3, MMP13, MMP14, and IL-1beta. ELISA was used to quantify IL-6 and IL-8 release. To examine the influence of collagen II signaling, specifically the role of MAPK p38, a p38-inhibitor was added prior to collagen treatment. Changes in IkappaB concentration were monitored by immunoblot analysis to detect NFkappaB signaling. Results indicated that incubation of PHCs with collagen II did produce a dose-dependent induction of MMP1, MMP3, MMP13, MMP14, as well as cytokines IL-1beta, IL-6, and IL-8. At the same time, inhibition of p38 and IkappaB degradation revealed that collagen II-dependent gene induction also involves MAPK p38 and NFkappaB signaling. Thus, we provide evidence for a collagen II-dependent feed-forward mechanism whereby collagen II induces first MMPs and pro-inflammatory cytokines and then release of collagen II fragments from mature collagen II fibers. This, in turn, induces more pro-inflammatory cytokines and MMPs, and the process is repeated, which results in the acceleration and perpetuation of cartilage matrix degradation.
Assuntos
Condrócitos/metabolismo , Colágeno Tipo II/metabolismo , Metaloproteinases da Matriz/metabolismo , Animais , Cartilagem/metabolismo , Galinhas , Humanos , Proteínas I-kappa B/metabolismo , Inflamação , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Articulação do Joelho/patologia , Sistema de Sinalização das MAP Quinases , Inibidor de NF-kappaB alfa , Osteoartrite , RatosRESUMO
Excessive matrix metalloproteinase (MMP) levels have been observed in wound fluid of impaired healing wounds. This is thought to interfere with granulation tissue formation as newly formed extracellular matrix and cytokines are degraded and the wound becomes deadlocked, unable to progress to the next healing stages. In the cleansing phase, associated with high MMP activity levels, hydroactive wound dressings containing polyacrylate superabsorber particles are particularly effective. We tested whether these particles can block MMP activity in wound fluid obtained from chronic venous leg ulcers. Polyacrylate superabsorber particles inhibited MMP activity by more than 87% in a fluorogenic peptide substrate assay. Further analysis revealed two underlying molecular mechanisms. First, experiments showed direct binding of MMPs to the particles. Secondly, polyacrylate superabsorber particles can bind Ca2+ and Zn2+ ions competing with MMPs for divalent ions required for enzymatic activity. Furthermore, we provide the first evidence in vivo that MMPs bind effectively to polyacrylate superabsorber particles within the hostile environment of chronic wounds. We conclude that polyacrylate superabsorber particles can rescue the highly proteolytic microenvironment of non-healing wounds from MMP activity so that more conductive conditions allow healing to proceed.
Assuntos
Resinas Acrílicas/farmacologia , Inibidores de Metaloproteinases de Matriz , Inibidores de Proteases/farmacologia , Ferimentos e Lesões/enzimologia , Doença Crônica , Humanos , Concentração de Íons de HidrogênioRESUMO
RNAi-mediated gene silencing is a recent, powerful tool to investigate gene function. Controlling for experimental factors such as transfection efficiencies, siRNA concentration, gene suppression levels, gene suppression kinetics, or non-specific effects is key to robust results. In this methods paper, we compare the efficiencies of different transfection reagents in primary human chondrocytes (PHCs). We investigated TAK1 gene suppression efficiencies and kinetics on the mRNA and protein level depending on the siRNA concentration used. Furthermore, we evaluated PKR, IL-6, and TNF-alpha induction, as well as IkappaB degradation and NFkappaB activation as control parameters of non-specific siRNA effects. PKR and IL-6 proved to be appropriate markers of cellular inflammatory responses resulting from siRNA transfection. In addition, we compared different siRNAs (silencing, non-silencing, classic 21-mer, and 25-mer stealth siRNA) with respect to their capacity to induce cellular inflammatory responses. We found the occurrence of cellular responses in PHCs to be a function of the specific siRNA sequence in use. Hence, it is essential to analyze and to compare gene silencing siRNAs and control siRNAs with respect to their off-target effects prior to any functional gene validation.