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1.
J Bone Joint Surg Am ; 104(8): 723-731, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-35192570

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) registries do not all use the same patient-reported outcome measures, limiting comparisons and preventing pooling of data for meta-analysis. Our objective was to create a statistical crosswalk to convert cohort and registry mean Knee Injury and Osteoarthritis Outcome Scores (KOOS) to International Knee Documentation Committee-Subjective Knee Form (IKDC-SKF) scores and vice versa to allow these comparisons. METHODS: Data from 3 ACL registries were pooled (n = 14,412) and were separated into a training data set (70% of the sample) or a validation data set (30% of the sample). The KOOS and the IKDC-SKF scores were available prior to the operation and at 1, 2, and 5 or 6 years postoperatively. We used equipercentile equating methods to create crosswalks in the training data set and examined accuracy in the validation data set as well as bootstrapping analyses to assess the impact of sample size on accuracy. RESULTS: Preliminary analyses suggested that crosswalks could be attempted: large correlations between scores on the 2 measures (r = 0.84 to 0.94), unidimensionality of scores, and subpopulation invariance were deemed sufficient. When comparing actual scores with crosswalked scores in the validation data set, negligible bias was observed at the group level; however, individual score deviations were variable. The crosswalks are successful for the group level only. CONCLUSIONS: Our crosswalks successfully convert between the KOOS and the IKDC-SKF scores to allow for a group-level comparison of registry and other cohort data. CLINICAL RELEVANCE: These crosswalks allow comparisons among different national ligament registries as well as other research cohorts and studies; they also allow data from different patient-reported outcome measures to be pooled for meta-analysis. These crosswalks have great potential to improve our understanding of recovery after ACL reconstruction and aid in our ongoing efforts to improve outcomes and patient satisfaction, as well as to allow the continued analysis of historical data.


Assuntos
Lesões do Ligamento Cruzado Anterior , Reconstrução do Ligamento Cruzado Anterior , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/métodos , Documentação , Humanos , Articulação do Joelho/cirurgia , Inquéritos e Questionários
3.
J Bone Joint Surg Am ; 103(16): 1473-1481, 2021 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-33999877

RESUMO

BACKGROUND: Anterior cruciate ligament (ACL) injuries can be treated with or without ACL reconstruction (ACLR), and more high-quality studies evaluating outcomes after the different treatment courses are needed. The purpose of the present study was to describe and compare 5-year clinical, functional, and physical activity outcomes for patients who followed our decision-making and treatment algorithm and chose (1) early ACLR with preoperative and postoperative rehabilitation, (2) delayed ACLR with preoperative and postoperative rehabilitation, or (3) progressive rehabilitation alone. Early ACLR was defined as that performed ≤6 months after the preoperative rehabilitation program, and late ACLR was defined as that performed >6 months after the preoperative rehabilitation program. METHODS: We included 276 patients from a prospective cohort study. The patients had been active in jumping, pivoting, and cutting sports before the injury and sustained a unilateral ACL injury without substantial concomitant knee injuries. The patients chose their treatment through a shared decision-making process. At 5 years, we assessed the International Knee Documentation Committee Subjective Knee Form (IKDC-SKF), Knee injury and Osteoarthritis Outcome Score (KOOS), Marx Activity Rating Scale, sports participation, quadriceps muscle strength, single-legged hop performance, and new ipsilateral and contralateral knee injuries. RESULTS: The 5-year follow-up rate was 80%. At 5 years, 64% of the patients had undergone early ACLR, 11% had undergone delayed ACLR, and 25% had had progressive rehabilitation alone. Understandably, the choices that participants made differed by age, concomitant injuries, symptoms, and predominantly level-I versus level-II preinjury activity level. There were no significant differences in any clinical, functional, or physical activity outcomes among the treatment groups. Across treatment groups, 95% to 100% of patients were still active in some kind of sports and 65% to 88% had IKDC-SKF and KOOS scores above the threshold for a patient acceptable symptom state. CONCLUSIONS: Patients with ACL injury who were active in jumping, pivoting, and cutting sports prior to injury; who had no substantial concomitant knee injuries; and who followed our decision-making and treatment algorithm had good 5-year knee function and high sport participation rates. Three of 4 patients had undergone ACLR within 5 years. There were no significant differences in any outcomes among patients treated with early ACLR, delayed ACLR, or progressive rehabilitation alone. LEVEL OF EVIDENCE: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Lesões do Ligamento Cruzado Anterior/terapia , Reconstrução do Ligamento Cruzado Anterior/métodos , Procedimentos Clínicos , Terapia por Exercício/métodos , Educação de Pacientes como Assunto/métodos , Adolescente , Adulto , Ligamento Cruzado Anterior/fisiopatologia , Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/estatística & dados numéricos , Atletas/estatística & dados numéricos , Tomada de Decisão Compartilhada , Delaware , Terapia por Exercício/organização & administração , Feminino , Seguimentos , Humanos , Masculino , Noruega , Educação de Pacientes como Assunto/organização & administração , Cuidados Pré-Operatórios/métodos , Estudos Prospectivos , Volta ao Esporte/estatística & dados numéricos , Tempo para o Tratamento/estatística & dados numéricos , Resultado do Tratamento , Adulto Jovem
4.
J Orthop Sports Phys Ther ; 50(9): 490-502, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32741324

RESUMO

OBJECTIVES: (1) To assess prognostic factors for patient-reported outcome measures (PROMs) and physical activity 2 to 10 years after anterior cruciate ligament reconstruction (ACLR) or anterior cruciate ligament (ACL) injury, and (2) to assess differences in prognostic factors between patients treated with ACLR and with rehabilitation alone. DESIGN: Prognosis systematic review. LITERATURE SEARCH: Systematic searches were performed in PubMed, Web of Science, and SPORTDiscus. STUDY SELECTION CRITERIA: We selected prospective cohort studies and randomized clinical trials that included adults or adolescents undergoing either ACLR or rehabilitation alone after ACL rupture. Studies had to assess the statistical association between potential prognostic factors (factors related to patient characteristics, injury, or knee symptoms/function measured at baseline or within 1 year) and outcomes (PROMs and physical activity). DATA SYNTHESIS: Our search yielded 997 references. Twenty studies met the inclusion criteria. Seven studies with low or moderate risk of bias remained for data synthesis. RESULTS: Moderate-certainty evidence indicated that concomitant meniscus and cartilage injuries were prognostic factors for worse PROMs 2 to 10 years after ACLR. Very low-certainty evidence suggested that body mass index, smoking, and baseline PROMs were prognostic factors for worse outcome. Very low-certainty evidence suggested that female sex and a worse baseline Marx Activity Rating Scale score were prognostic factors for a worse Marx Activity Rating Scale score 2 to 10 years after ACLR. There was a lack of studies on prognostic factors after rehabilitation alone. CONCLUSION: Concomitant meniscus and cartilage injuries were prognostic factors for worse long-term PROMs after ACLR. The certainty was very low for other prognostic factors. J Orthop Sports Phys Ther 2020;50(9):490-502. Epub 1 Aug 2020. doi:10.2519/jospt.2020.9451.


Assuntos
Lesões do Ligamento Cruzado Anterior/complicações , Lesões do Ligamento Cruzado Anterior/terapia , Traumatismos do Joelho/complicações , Ligamentos Articulares/lesões , Medidas de Resultados Relatados pelo Paciente , Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior , Índice de Massa Corporal , Exercício Físico , Feminino , Humanos , Traumatismos do Joelho/terapia , Masculino , Prognóstico , Fatores de Risco , Fatores Sexuais , Fumar/efeitos adversos
5.
Am J Sports Med ; 48(8): 1953-1960, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32515989

RESUMO

BACKGROUND: The selection of patient-reported outcome measures (PROMs) is essential for obtaining meaningful information to treat a patient, determine a plan of care, and make clinical decisions; however, the process of selecting PROMs for clinical care is difficult, with the need to balance these multiple factors. Variation makes it difficult to compare data across providers and studies. HYPOTHESIS/PURPOSE: The purpose was to determine the responsiveness of 4 PROMs via effect size and the presence of a ceiling effect in the 5 years after anterior cruciate ligament reconstruction (ACLR). We hypothesized that the single-item Global Rating Scale (GRS) would have an effect size and ceiling effect similar to the commonly used legacy PROMs. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 2. METHODS: Of the 300 participants, 218 had ACLR, completed postoperative progressive criterion-based rehabilitation early after surgery, and were followed for 5 years. We collected data based on the GRS, the Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS), the International Knee Documentation Committee-Subjective Knee Form (IKDC-SKF), and the KOOS (Knee injury and Osteoarthritis Outcome Score) before and after training and at 6, 12, 24, and 60 months after ACLR. RESULTS: The IKDC-SKF had the largest effect sizes and lowest ceiling effects. The GRS had a similar size and change in both effect size and ceiling effect when compared with the longer PROMs. The GRS and IKDC-SKF had a correlation of 0.72, and the GRS had a minimal detectable change of 2.9 or 4.8, depending on methodology. CONCLUSION: The GRS responded similarly to the IKDC-SKF, KOS-ADLS, and KOOS and was responsive to patient change. The ease of use and patient-specific nature of the question means that it may be appropriate to use the GRS in clinical care as a consistent measure throughout the course of rehabilitation.


Assuntos
Lesões do Ligamento Cruzado Anterior/cirurgia , Reconstrução do Ligamento Cruzado Anterior/reabilitação , Atividades Cotidianas , Adolescente , Adulto , Lesões do Ligamento Cruzado Anterior/reabilitação , Estudos de Coortes , Humanos , Articulação do Joelho/cirurgia , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Adulto Jovem
6.
Adv Exp Med Biol ; 854: 443-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26427444

RESUMO

To compare patterns of gene expression following preconditioning cyclic light rearing versus preconditioning aerobic exercise. BALB/C mice were preconditioned either by rearing in 800 lx 12:12 h cyclic light for 8 days or by running on treadmills for 9 days, exposed to toxic levels of light to cause light-induced retinal degeneration (LIRD), then sacrificed and retinal tissue harvested. Subsets of mice were maintained for an additional 2 weeks and for assessment of retinal function by electroretinogram (ERG). Both preconditioning protocols partially but significantly preserved retinal function and morphology and induced similar leukemia inhibitory factor (LIF) gene expression pattern. The data demonstrate that exercise preconditioning and cyclic light preconditioning protect photoreceptors against LIRD and evoke a similar pattern of retinal LIF gene expression. It may be that similar stress response pathways mediate the protection provided by the two preconditioning modalities.


Assuntos
Fotoperíodo , Condicionamento Físico Animal/fisiologia , Degeneração Retiniana/genética , Transcriptoma/genética , Animais , Eletrorretinografia , Fator Inibidor de Leucemia/genética , Luz/efeitos adversos , Masculino , Camundongos Endogâmicos BALB C , Retina/metabolismo , Retina/patologia , Retina/efeitos da radiação , Degeneração Retiniana/etiologia , Degeneração Retiniana/fisiopatologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcriptoma/efeitos da radiação
7.
Cancer Biol Ther ; 16(11): 1626-40, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26418968

RESUMO

Integrins function in collective migration both as major receptors for extracellular matrix and by crosstalk to adherens junctions. Despite extensive research, important questions remain about how integrin signaling mechanisms are integrated into collective migration programs. Tetraspanins form cell surface complexes with a subset of integrins and thus are good candidates for regulating the balance of integrin functional inputs into cell-matrix and cell-cell interactions. For example, tetraspanin CD151 directly associates with α3ß1 integrin in carcinoma cells and promotes rapid α3ß1-dependent single cell motility, but CD151 also promotes organized adherens junctions and restrains collective carcinoma cell migration on 2D substrates. However, the individual roles of CD151s integrin partners in CD151s pro-junction activity in carcinoma cells were not well understood. Here we find that CD151 promotes organized carcinoma cell junctions via α3ß1 integrin, by a mechanism that requires the a3b1 ligand, laminin-332. Loss of CD151 promotes collective 3D invasion and growth in vitro and in vivo, and the enhanced invasion of CD151-silenced cells is α3 integrin dependent, suggesting that CD151 can regulate the balance between α3ß1s pro-junction and pro-migratory activities in collective invasion. An analysis of human cancer cases revealed that changes in CD151 expression can be linked to either better or worse clinical outcomes depending on context, including potentially divergent roles for CD151 in different subsets of breast cancer cases. Thus, the role of the CD151-α3ß1 complex in carcinoma progression is context dependent, and may depend on the mode of tumor cell invasion.


Assuntos
Neoplasias da Mama/metabolismo , Integrina alfa3beta1/fisiologia , Junções Intercelulares/metabolismo , Tetraspanina 24/fisiologia , Animais , Antígenos CD , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Caderinas/metabolismo , Moléculas de Adesão Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular , Intervalo Livre de Doença , Feminino , Humanos , Camundongos Nus , Invasividade Neoplásica , Transplante de Neoplasias , Calinina
9.
J Invest Dermatol ; 132(9): 2148-57, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22592159

RESUMO

We have shown that autocrine proliferation of human keratinocytes (KCs) is strongly dependent upon amphiregulin (AREG), whereas blockade of heparin-binding EGF-like growth factor (HB-EGF) inhibits KC migration in scratch wound assays. Here we demonstrate that expression of soluble HB-EGF (sHB-EGF) or full-length transmembrane HB-EGF (proHB-EGF), but not proAREG, results in profound increases in KC migration and invasiveness in monolayer culture. Coincident with these changes, HB-EGF significantly decreases mRNA expression of several epithelial markers including keratins 1, 5, 10, and 14 while increasing expression of markers of cellular motility including SNAI1, ZEB1, COX-2, and MMP1. Immunostaining revealed HB-EGF-induced expression of the mesenchymal protein vimentin and decreased expression of E-cadherin, as well as nuclear translocation of ß-catenin. Suggestive of a trade-off between KC motility and proliferation, overexpression of HB-EGF also reduced KC growth by >90%. We also show that HB-EGF is strongly induced in regenerating epidermis after partial-thickness wounding of human skin. Taken together, our data suggest that expression of HB-EGF in human KCs triggers a migratory and invasive phenotype with many features of epithelial-mesenchymal transition (EMT), which may be beneficial in the context of cutaneous wound healing.


Assuntos
Movimento Celular , Transição Epitelial-Mesenquimal , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Queratinócitos/fisiologia , Anfirregulina , Caderinas/biossíntese , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Proliferação de Células , Família de Proteínas EGF , Glicoproteínas/biossíntese , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Queratinócitos/patologia , Queratinas/biossíntese , Transporte Proteico , Vimentina/biossíntese , Cicatrização , beta Catenina/biossíntese
10.
J Invest Dermatol ; 130(8): 2031-40, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20428186

RESUMO

The EGFR ligand amphiregulin (AREG) has been implicated as an important autocrine growth factor in several epithelial malignancies and in psoriasis, a hyperproliferative skin disorder. To characterize the mechanisms by which AREG regulates autocrine epithelial cell growth, we transduced human keratinocytes (KCs) with lentiviral constructs expressing tetracycline (TET)-inducible small hairpin RNA (shRNA). TET-induced expression of AREG shRNA markedly reduced autocrine extracellular signal-regulated kinase phosphorylation, strongly inhibited autocrine KC growth with an efficiency similar to metalloproteinase and EGFR inhibitors, and induced several markers of KC differentiation, including keratins 1 and 10. Addition of various concentrations of exogenous EGFR ligands to KC cultures reversed the growth inhibition in response to AREG-blocking antibodies but not to shRNA-mediated AREG knockdown. Lentivirus-mediated expression of the full-length AREG transmembrane (TM) precursor, but not of the AREG extracellular domain, markedly reversed the shRNA-mediated growth inhibition and morphological changes, and strongly reduced the induction of multiple markers of KC differentiation. Taken together, our data show that autocrine human KC growth is highly dependent on the AREG TM precursor protein and strongly suggest a previously unreported function of the metalloproteinase-processed carboxy (C)-terminal domain of AREG.


Assuntos
Comunicação Autócrina/fisiologia , Glicoproteínas/química , Glicoproteínas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/química , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , Anfirregulina , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Linhagem Celular , Família de Proteínas EGF , Receptores ErbB/metabolismo , Glicoproteínas/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Lentivirus/genética , Ligantes , Fosforilação/fisiologia , Precursores de Proteínas/metabolismo , Estrutura Terciária de Proteína , RNA Interferente Pequeno , Transdução de Sinais/fisiologia , Transdução Genética
11.
J Invest Dermatol ; 130(1): 295-304, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19609315

RESUMO

Human keratinocytes (KCs) express multiple EGF receptor (EGFR) ligands; however, their functions in specific cellular contexts remain largely undefined. To address this issue, first we measured mRNA and protein levels for multiple EGFR ligands in KCs and skin. Amphiregulin (AREG) was by far the most abundant EGFR ligand in cultured KCs, with >19 times more mRNA and >7.5 times more shed protein than any other family member. EGFR ligand expression in normal skin was low (<8 per thousand of RPLP0/36B4); however, HB-EGF and AREG mRNAs were strongly induced in human skin organ culture. KC migration in scratch wound assays was highly metalloproteinase (MP)- and EGFR dependent, and was markedly inhibited by EGFR ligand antibodies. However, lentivirus-mediated expression of soluble HB-EGF, but not soluble AREG, strongly enhanced KC migration, even in the presence of MP inhibitors. Lysophosphatidic acid (LPA)-induced ERK phosphorylation was also strongly EGFR and MP dependent and markedly inhibited by neutralization of HB-EGF. In contrast, autocrine KC proliferation and ERK phosphorylation were selectively blocked by neutralization of AREG. These data show that distinct EGFR ligands stimulate KC behavior in different cellular contexts, and in an MP-dependent fashion.


Assuntos
Movimento Celular/fisiologia , Glicoproteínas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Queratinócitos/metabolismo , Metaloproteases/metabolismo , Anfirregulina , Comunicação Autócrina/fisiologia , Divisão Celular/fisiologia , Células Cultivadas , Família de Proteínas EGF , Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glicoproteínas/genética , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Queratinócitos/citologia , Lentivirus/genética , Ligantes , Lipopolissacarídeos/farmacologia , Metaloproteases/antagonistas & inibidores , Técnicas de Cultura de Órgãos , Fosforilação/efeitos dos fármacos , Fosforilação/fisiologia , RNA Mensageiro/metabolismo , Transdução de Sinais/fisiologia , Pele/citologia
12.
J Cell Sci ; 122(Pt 13): 2263-73, 2009 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-19509057

RESUMO

Tetraspanins regulate integrin-dependent tumor cell interactions with the extracellular matrix. Here we show that tetraspanin CD151, which plays critical roles in regulating the adhesion and motility of individual tumor cells, is also an important regulator of collective tumor cell migration. Near total silencing of CD151 destabilizes E-cadherin-dependent carcinoma cell-cell junctions and enhances the collective migration of intact tumor cell sheets. This effect does not depend on reduced E-cadherin cell-surface expression or intrinsic adhesivity, or on obvious disruptions in the E-cadherin regulatory complex. Instead, the loss of CD151 causes excessive RhoA activation, loss of actin organization at cell-cell junctions, and increased actin stress fibers at the basal cell surface. Cell-cell contacts within CD151-silenced monolayers display a nearly threefold increase in remodeling rate and a significant reduction in lifespan as compared to cell-cell contacts within wild-type monolayers. CD151 re-expression restores junctional stability, as does acute treatment of CD151-silenced cells with a cell-permeable RhoA inhibitor. However, a CD151 mutant with impaired association with alpha3beta1 integrin fails to restore junctional organization. These data reveal that, in addition to its roles in regulating tumor cell-substrate interactions, CD151 is also an important regulator of the stability of tumor cell-cell interactions, potentially through its interaction with alpha3beta1 integrin. This could help to explain the phenotypes in human patients and mice lacking CD151.


Assuntos
Antígenos CD/metabolismo , Carcinoma , Movimento Celular/fisiologia , Junções Intercelulares/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Animais , Antígenos CD/genética , Caderinas/genética , Caderinas/metabolismo , Carcinoma/metabolismo , Carcinoma/patologia , Linhagem Celular , Ativação Enzimática , Inativação Gênica , Humanos , Integrina alfa3beta1/metabolismo , Interferência de RNA , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fibras de Estresse/metabolismo , Tetraspanina 24 , Proteína rhoA de Ligação ao GTP/genética
13.
Mol Pharmacol ; 67(4): 1145-57, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15615697

RESUMO

c-Src potentiates proliferation, survival, and invasiveness in response to epidermal growth factor (EGF) in human mammary carcinoma cells. Tyrosine (Tyr) 845 of ErbB1 is phosphorylated by Src and has been implicated in control of malignant behavior. Although several lines of evidence also suggest important interactions of ErbB and Src family kinase signaling in normal epithelial cells, little is known about the mechanism of this interaction. Studying normal human keratinocytes (NHKs), here we demonstrate strong expression of the Src family kinases Src, Yes, and Fyn; Src family kinase-dependent stimulation of Tyr 845 by EGF; and potent inhibition of NHK proliferation and migration by two Src family kinase inhibitors PP1 and PD173952. EGF-stimulated extracellular signal-regulated kinase (ERK) phosphorylation occurred at much lower concentrations of EGF than required to phosphorylate Tyr 845. Moreover, the effect of Src family kinase inhibitors on EGF-stimulated ERK phosphorylation was transient, prompting a search for other targets of Src family kinase action. By enzyme-linked immunosorbent assay analysis, we found that three different Src family kinase inhibitors [6-(2,6-dichlorophenyl)-8-methyl-2-(4-morpholin-4-ylphenylamino)-8H-pyrido[2,3-d]pyrimidin-7-one (PD173952), 4-amino-5-(4-methylphenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP1), and 2-oxo-3-(4,5,6,7-tetrahydro-1H-indol-2-ylmethylene)-2,3-dihydro-1H-indole-5-sulfonic acid dimethylamide (SU6656)] markedly inhibited elaboration of soluble amphiregulin by NHKs. The ErbB inhibitor PD158780 and the mitogen-activated protein kinase kinase inhibitor U0126 also markedly inhibited NHK proliferation, migration, and amphiregulin production. Together, these observations demonstrate that one or more Src family kinases act upstream as well as downstream of ErbB1 to promote amphiregulin-dependent autocrine stimulation of NHKs and suggest that autocrine NHK proliferation is more dependent upon ERK activation than upon Tyr 845 phosphorylation.


Assuntos
Receptores ErbB/fisiologia , Glicoproteínas/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Queratinócitos/metabolismo , Transdução de Sinais , Quinases da Família src/antagonistas & inibidores , Anfirregulina , Células Cultivadas , Família de Proteínas EGF , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Fosforilação , Pirimidinas/farmacologia , Quinases da Família src/fisiologia
14.
Mol Biol Cell ; 15(9): 4299-309, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15254267

RESUMO

ErbB signaling through extracellular signal-regulated kinase (ERK) has been implicated in regulating the expression of ErbB ligands in hyperproliferative skin disorders and wound healing. Here, we characterize the process of autocrine ERK activation in cultured normal human keratinocytes (NHKs) subjected to growth factor (GF) deprivation. Basal ERK phosphorylation was lower after 48 h than after 24 h of GF deprivation, and lowest at 30-60 min after an additional medium change. ERK phosphorylation was markedly increased by low concentrations of epidermal growth factor (EGF) (0.2-1 ng/ml) that provoked only a limited increase in ErbB1 tyrosine phosphorylation and internalization. Basal ErbB tyrosine phosphorylation and ERK phosphorylation were inhibited by two different ErbB receptor tyrosine kinase inhibitors, by the ErbB1-specific neutralizing monoclonal antibody 225 IgG, by two different metalloproteinase inhibitors, and by neutralizing antibodies against amphiregulin (AR). In contrast, these responses were unaffected by neutralizing antibodies against other ErbB1 ligands or the ErbB2 inhibitors geldanamycin and AG825. The time course of autocrine ERK phosphorylation correlated with the appearance of soluble AR, and two different metalloproteinase inhibitors blocked AR release. These results define an amphiregulin- and ErbB1-dependent mechanism by which autocrine ERK activation is maintained in NHKs, even when ErbB1 autophosphorylation and internalization are limited.


Assuntos
Receptores ErbB/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Glicoproteínas/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Queratinócitos/metabolismo , Metaloproteases/metabolismo , Anfirregulina , Anticorpos Monoclonais , Células Cultivadas , Meios de Cultura Livres de Soro , Família de Proteínas EGF , Ativação Enzimática , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/imunologia , Glicoproteínas/antagonistas & inibidores , Glicoproteínas/imunologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Sistema de Sinalização das MAP Quinases , Testes de Neutralização , Fosforilação
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