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1.
FASEB J ; 38(6): e23560, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38498349

RESUMO

Federal funding for research has immediate and long-term economic impact. Since federal research funding is regionally concentrated and not geographically distributed, the benefits are not fully realized in some regions of the country. The Established (previously Experimental) Program to Stimulate Competitive Research (EPSCoR) programs at several agencies, for example, the National Science Foundation, and the Institutional Development Award (IDeA) program at the National Institutes of Health were created to increase competitiveness for funding in states with historically low levels of federal funding. The Centers of Biomedical Research Excellence (CoBRE) award program is a component of the IDeA program. The CoBRE grants support research core facilities to develop research infrastructure. These grants also support the research projects of junior investigators, under the guidance of mentoring teams of senior investigators, to develop human resources at these institutions. Few studies have assessed the effectiveness of these programs. This study examines the investment and outcomes of the CoBRE grants from 2000 through 2022. The maturation of junior investigators into independently funded principal investigators is comparable to other mentoring programs supported by NIH. The investment in research cores resulted in substantial research productivity, measured by publications. Despite the successes of individual investigators and increased research infrastructure and productivity, the geographic distribution of federal and NIH research dollars has not changed. These results will be informative in consideration of policies designed to enhance the geographic distribution of federal research dollars.


Assuntos
Pesquisa Biomédica , Tutoria , Estados Unidos , Humanos , National Institutes of Health (U.S.) , Organização do Financiamento , Pesquisadores
2.
bioRxiv ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-37577479

RESUMO

Federal funding for research has immediate and long-term economic impact. Since federal research funding is regionally concentrated and not geographically distributed, the benefits are not fully realized in some regions of the country. The Established (previously Experimental) Program to Stimulate Competitive Research (EPSCoR) programs at several agencies, e.g. the National Science Foundation, and the Institutional Development Award (IDeA) program at the National Institutes of Health were created to increase competitiveness for funding in states with historically low levels of federal funding. The Centers of Biomedical Research Excellence (CoBRE) award program is a component of the IDeA program. The CoBRE grants support research core facilities to develop research infrastructure. These grants also support the research projects of junior investigators, under the guidance of mentoring teams of senior investigators, to develop human resources at these institutions. Few studies have assessed the effectiveness of these programs. This study examines the investment and outcomes of the CoBRE grants from 2000 through 2022. The maturation of junior investigators into independently funded principal investigators is comparable to other mentoring programs supported by NIH. The investment in research cores resulted in substantial research productivity, measured by publications. Despite the successes of individual investigators and increase research infrastructure and productivity, the geographic distribution of federal and NIH research dollars has not changed. These results will be informative in consideration of policies designed to enhance the geographic distribution of federal research dollars.

3.
BMC Med Educ ; 23(1): 579, 2023 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-37587476

RESUMO

BACKGROUND: Traditionally, doctoral student education in the biomedical sciences relies on didactic coursework to build a foundation of scientific knowledge and an apprenticeship model of training in the laboratory of an established investigator. Recent recommendations for revision of graduate training include the utilization of graduate student competencies to assess progress and the introduction of novel curricula focused on development of skills, rather than accumulation of facts. Evidence demonstrates that active learning approaches are effective. Several facets of active learning are components of problem-based learning (PBL), which is a teaching modality where student learning is self-directed toward solving problems in a relevant context. These concepts were combined and incorporated in creating a new introductory graduate course designed to develop scientific skills (student competencies) in matriculating doctoral students using a PBL format. METHODS: Evaluation of course effectiveness was measured using the principals of the Kirkpatrick Four Level Model of Evaluation. At the end of each course offering, students completed evaluation surveys on the course and instructors to assess their perceptions of training effectiveness. Pre- and post-tests assessing students' proficiency in experimental design were used to measure student learning. RESULTS: The analysis of the outcomes of the course suggests the training is effective in improving experimental design. The course was well received by the students as measured by student evaluations (Kirkpatrick Model Level 1). Improved scores on post-tests indicate that the students learned from the experience (Kirkpatrick Model Level 2). A template is provided for the implementation of similar courses at other institutions. CONCLUSIONS: This problem-based learning course appears effective in training newly matriculated graduate students in the required skills for designing experiments to test specific hypotheses, enhancing student preparation prior to initiation of their dissertation research.


Assuntos
Aprendizagem Baseada em Problemas , Projetos de Pesquisa , Humanos , Estudantes , Pensamento , Currículo
4.
FASEB Bioadv ; 5(3): 131-148, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36876299

RESUMO

Training of doctoral students as part of the next generation of the biomedical workforce is essential for sustaining the scientific enterprise in the United States. Training primarily occurs at institutions of higher education, and these trainees comprise an important part of the workforce at these institutions. Federal investment in the support of doctoral students in the biological and biomedical sciences is distributed differently than the distribution of students across different types of institutions, for example, public vs private. Institutions in states that historically receive less federal support for research also receive less support for doctoral student training. Doctorates at different types of institution exhibit little difference in research productivity, with the exception of citations, and subsequent receipt of additional NIH awards. Thus, training outcomes, which are related to the quality of the student and training environment, are similar across different institutions. Research productivity of doctoral students does not correlate with the number of F31s awarded to an institution. Factors that correlate with F31 funding include R01 funding levels and program size. The findings suggest strategies for institutions to increase success at securing F31s and modification of policy to promote more equitable distribution of F31s across institutions.

5.
BMC Med Educ ; 22(1): 419, 2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35650575

RESUMO

BACKGROUND: Analysis of the biomedical workforce and graduate education have produced recommendations for modifications of pre-doctoral training to broadly prepare trainees for wider ranging scientific careers. Development of training in professional skills is widely recommended, but details of implementation are not widely available. In alignment with these recommendations, we have incorporated professional skills training into the biomedical science graduate curriculum at West Virginia University. An important component of the training is developing conflict resolution and negotiation skills. This training will provide useful skills for academic careers, non-academic careers and life situations outside of the workplace. Conflict resolution/negotiation skills are also relevant in managing issues in diversity, equity and inclusivity. We report our experience in developing this component of the training program, provide an overview of the approach to delivery and practice of skills, and provide an analysis of the reception and effectiveness of the training. METHODS: Evaluation of effectiveness of training used the principals of the Kirkpatrick Four Level Model of Evaluation. At the end of the course, students completed a questionnaire about their perceptions of training and were asked how they would respond to different scenarios requiring conflict resolution/negotiation skills. Several months later, students were surveyed to determine if they used some of these skills and/or witnessed situations where these skills would be useful. RESULTS: We report our experience in developing conflict resolution/negotiation training in our graduate curriculum, provide an overview of the approach to delivery and practice of skills, and provide an analysis of the reception and effectiveness of the training. The results suggest this training meets a need and is effective. Importantly, these materials provide a template for others wishing to implement similar training in their curricula. CONCLUSIONS: Conflict resolution and negotiation training meets a need in graduate education. A mixed approach using didactic and interactive components spaced out over time appears to be an effective method of training.


Assuntos
Currículo , Negociação , Educação de Pós-Graduação , Humanos , Estudantes , Universidades
6.
FASEB Bioadv ; 3(7): 482-489, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34258517

RESUMO

Recent reports express concern about the sustainability of the biomedical research enterprise in its current form. Recurring concerns include the predictability and sustainability of funding for research, regulatory burden and training the next generation in the biomedical workforce. One specific concern is the duration of training periods during pre-doctoral and post-doctoral studies. This article addresses the issue of time-to-degree (TTD) for doctorates. Many reports stress the importance of shortening the TTD, but provide no recommendations to achieve this goal. Herein, factors potentially affecting TTD are discussed and one mechanism that harmonizes undergraduate and graduate programs is proposed as a strategy to reduce the TTD.

7.
FASEB Bioadv ; 3(2): 83-93, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33615153

RESUMO

Analyses of the biomedical research workforce, the biomedical research enterprise, and its sustainability have identified a number of threats and offered many solutions to alleviate the problems. While a number of these solutions have been implemented, one solution that has not been broadly adopted, despite being widely recommended, is to increase the number of staff scientists and reduce dependency on trainees. The perceived impediment of this is the cost. This paper explores the costs associated with laboratory personnel and the benefits, in terms of productivity, associated with different positions in the workforce. The results of this cost-benefit analysis depend upon the values assigned to different metrics of productivity by individuals and institutions. If first and senior author publications are the most important metrics of productivity, a trainee-dependent workforce is much more cost effective. If total publications are the most valued metric of productivity, the cost effectiveness of trainee and staff scientists is reasonably equitable. This analysis provides data for consideration when making personnel decisions and for the continued discussion of modification of the biomedical research workforce. It also provides insight into the incentives for modification of the workforce at the grass roots, which must be considered by institutions genuinely committed to workforce modification to sustain the biomedical research enterprise.

8.
Mol Cancer Res ; 19(5): 784-798, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33500360

RESUMO

Several master transcription factors (TF) can activate the epithelial-to-mesenchymal transition (EMT). However, their individual and combinatorial contributions to EMT in breast cancer are not defined. We show that overexpression of EMT-TFs individually in epithelial cells upregulated endogenous SNAI2, ZEB1/2, TCF4, and TWIST1/2 as a result of positive feedback mediated in part by suppression of their negative regulator miRNAs miR200s/203/205. We identified TCF4 as a potential new target of miR200s. Expression of ZEB1/2 strongly correlated with the mesenchymal phenotype in breast cancer cells, with the CD24-/CD44+ stemness profile, and with lower expression of core epithelial genes in human breast tumors. Knockdown of EMT-TFs identified the key role of ZEB1 and its functional cooperation with other EMT-TFs in the maintenance of the mesenchymal state. Inducible ZEB1+2 knockdown in xenograft models inhibited pulmonary metastasis, emphasizing their critical role in dissemination from primary site and in extravasation. However, ZEB1+2 depletion one-week after intravenous injection did not inhibit lung colonization, suggesting that ZEB1/2 and EMT are not essential for macrometastatic outgrowth. These results provide strong evidence that EMT is orchestrated by coordinated expression of several EMT-TFs and establish ZEB1 as a key master regulator of EMT and metastasis in breast cancer. IMPLICATIONS: The EMT program is orchestrated by coordinated expression of multiple EMT transcription factors, whereas ZEB1 integrates the EMT master regulatory network and plays the major role in promoting EMT and metastasis.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fatores de Transcrição/metabolismo , Animais , Neoplasias da Mama/genética , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Transição Epitelial-Mesenquimal , Feminino , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos NOD , MicroRNAs/genética , MicroRNAs/metabolismo , Metástase Neoplásica , Fatores de Transcrição/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/genética , Homeobox 2 de Ligação a E-box com Dedos de Zinco/metabolismo , Homeobox 1 de Ligação a E-box em Dedo de Zinco/genética , Homeobox 1 de Ligação a E-box em Dedo de Zinco/metabolismo
9.
Elife ; 62017 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-29063834

RESUMO

Numerous concerns have been raised about the sustainability of the biomedical research enterprise in the United States. Improving the postdoctoral training experience is seen as a priority in addressing these concerns, but even identifying who the postdocs are is made difficult by the multitude of different job titles they can carry. Here, we summarize the detrimental effects that current employment structures have on training, compensation and benefits for postdocs, and argue that academic research institutions should standardize the categorization and treatment of postdocs. We also present brief case studies of two institutions that have addressed these challenges and can provide models for other institutions attempting to enhance their postdoctoral workforces and improve the sustainability of the biomedical research enterprise.


Assuntos
Pesquisa Biomédica , Mobilidade Ocupacional , Emprego/normas , Pesquisadores , Humanos , Estados Unidos , Recursos Humanos
10.
PLoS One ; 12(2): e0172136, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28222177

RESUMO

Focal adhesion kinase is an essential nonreceptor tyrosine kinase that plays an important role in development, in homeostasis and in the progression of human disease. Multiple stimuli activate FAK, which requires a change in structure from an autoinhibited to activated conformation. In the autoinhibited conformation the FERM domain associates with the catalytic domain of FAK and PI(4,5)P2 binding to the FERM domain plays a role in the release of autoinhibition, activating the enzyme. An in silico model of FAK/PI(4,5)P2 interaction suggests that residues on the catalytic domain interact with PI(4,5)P2, in addition to the known FERM domain PI(4,5)P2 binding site. This study was undertaken to test the significance of this in silico observation. Mutations designed to disrupt the putative PI(4,5)P2 binding site were engineered into FAK. These mutants exhibited defects in phosphorylation and failed to completely rescue the phenotype associated with fak -/- phenotype fibroblasts demonstrating the importance of these residues in FAK function. The catalytic domain of FAK exhibited PI(4,5)P2 binding in vitro and binding activity was lost upon mutation of putative PI(4,5)P2 binding site basic residues. However, binding was not selective for PI(4,5)P2, and the catalytic domain bound to several phosphatidylinositol phosphorylation variants. The mutant exhibiting the most severe biological defect was defective for phosphatidylinositol phosphate binding, supporting the model that catalytic domain phospholipid binding is important for biochemical and biological function.


Assuntos
Domínio Catalítico , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Fosfolipídeos/metabolismo , Animais , Linhagem Celular , Fibroblastos/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/fisiologia , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Camundongos , Fosfatos de Fosfatidilinositol/metabolismo , Fosforilação
11.
Cancer Cell ; 25(5): 551-2, 2014 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-24823631

RESUMO

In this issue of Cancer Cell, Li and colleagues demonstrate that the hematopoietic transcription factor Aiolos (named after the Wind God of Greek mythology) confers anoikis resistance in lung tumor cells through repression of cell adhesion-related genes including the mechanosensor p66Shc.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Fator de Transcrição Ikaros/metabolismo , Neoplasias Pulmonares/genética , Proteínas Adaptadoras da Sinalização Shc/genética , Humanos , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src
12.
Mol Cancer Res ; 11(6): 651-64, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23512980

RESUMO

The Src homology phosphotyrosyl phosphatase 2 (SHP2) is a positive effector of receptor tyrosine kinases (RTK) signaling. Furthermore, SHP2 is known to promote cell migration and invasiveness, key steps in cancer metastasis. To date, however, the mechanism by which SHP2 regulates cell movement is not fully understood. In the current report, a new role for SHP2 in regulating cell migration has been suggested. We show that SHP2 mediates lamellipodia persistence and cell polarity to promote directional cell migration in the MDA-MB231 and the MDA-MB468 basal-like and triple-negative breast cancer cell lines. We further show that SHP2 modulates the activity of focal adhesion kinase (FAK) by dephosphorylating pTyr397, the autophosphorylation site that primes FAK function. Because hyperactivation of FAK is known to counter the maturation of nascent focal complexes to focal adhesions, we propose that one of the mechanisms by which SHP2 promotes lamellipodia persistence is by downregulating FAK activity through dephosphorylation of pTyr397. The finding that inhibition of FAK activity partially restores EGF-induced lamellipodia persistence and cell migration in SHP2-silenced cells supports our proposition that SHP2 promotes growth factor-induced cell movement by acting, at least in part, on FAK. However, the effect of SHP2 inhibition in nonstimulated cells seems FAK independent as there was no significant difference between the control and the SHP2-silenced cells in pY397-FAK levels. Also, FAK inhibition did not rescue Golgi orientation defects in SHP2-silenced cells, suggesting that SHP2 acts through other mechanisms to promote cell polarity.


Assuntos
Movimento Celular/efeitos dos fármacos , Fator de Crescimento Epidérmico/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 11/metabolismo , Pseudópodes/metabolismo , Animais , Linhagem Celular Tumoral , Ativação Enzimática/efeitos dos fármacos , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Inativação Gênica/efeitos dos fármacos , Humanos , Camundongos , Fosforilação/efeitos dos fármacos , Fosfotirosina/metabolismo , Transporte Proteico/efeitos dos fármacos , Pseudópodes/efeitos dos fármacos , RNA Interferente Pequeno/metabolismo , Cicatrização/efeitos dos fármacos
13.
Biochemistry ; 51(11): 2213-23, 2012 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-22372511

RESUMO

Focal adhesion kinase (FAK), a key regulator of cell adhesion and migration, is overexpressed in many types of cancer. The C-terminal focal adhesion targeting (FAT) domain of FAK is necessary for proper localization of FAK to focal adhesions and subsequent activation. Phosphorylation of Y926 in the FAT domain by the tyrosine kinase Src has been shown to promote metastasis and invasion in vivo by linking the FAT domain to the MAPK pathway via its interaction with growth factor receptor-bound protein 2. Several groups have reported that inherent conformational dynamics in the FAT domain likely regulate phosphorylation of Y926; however, what regulates these dynamics is unknown. In this paper, we demonstrate that there are two sites of in vitro Src-mediated phosphorylation in the FAT domain: Y926, which has been shown to affect FAK function in vivo, and Y1008, which has no known biological role. The phosphorylation of these two tyrosine residues is pH-dependent, but this does not reflect the pH dependence of Src kinase activity. Circular dichroism and nuclear magnetic resonance data indicate that the stability and conformational dynamics of the FAT domain are sensitive to changes in pH over a physiological pH range. In particular, regions of the FAT domain previously shown to regulate phosphorylation of Y926 as well as regions near Y1008 show pH-dependent dynamics on the microsecond to millisecond time scale.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Quinases da Família src/metabolismo , Sítios de Ligação , Adesão Celular , Concentração de Íons de Hidrogênio , Fosforilação , Domínios de Homologia de src
14.
Biomol Concepts ; 3(3): 225-40, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25436535

RESUMO

Abstract Focal adhesion kinase (FAK) is a non-receptor protein tyrosine kinase that is highly expressed or activated in many human cancers. Under specific scenarios, FAK can regulate cell proliferation, cell survival, cell migration and invasion, and has been implicated in the control of tumorigenesis and metastasis. FAK has both catalytic and scaffolding activity, and triggers downstream signals by activation of a number of pathways, including the Ras/mitogen-activated protein kinase pathway, the phosphatidylinositol 3'-kinase/Akt pathway, and Rho family GTPases. Recent evidence also suggests novel signaling interactions between FAK and p53. These signaling events were defined primarily from studies on cells in culture, and elucidating which of these signaling pathways are pathologically relevant downstream of FAK in human cancer remains an important goal in determining the molecular mechanisms of tumorigenesis and metastasis. This review discusses select evidence of these signaling pathways with an emphasis on studies linking these to animal models of cancer and human disease. The role of FAK in the process of epithelial-to-mesenchymal transition and in cancer stem cells and recent therapeutic advances targeting FAK are also discussed.

15.
Int Rev Cell Mol Biol ; 288: 185-225, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21482413

RESUMO

Focal adhesion kinase (FAK) and proline-rich tyrosine kinase 2 (Pyk2) are closely related nonreceptor protein tyrosine kinases. FAK can regulate cell proliferation, survival, and motility, and plays an essential role in development. Pyk2 shares some functions with FAK but is a nonessential gene product during development. Recent discoveries related to FAK and Pyk2 structure have provided important insights into the regulatory mechanisms of catalytic activity, molecular basis of assembly of signaling complexes, and the transmission of downstream signals. This chapter reviews these advances in FAK/Pyk2 structure/function, compares and contrasts features of these kinases, and discusses new drug discoveries in the context of molecular structure.


Assuntos
Proteína-Tirosina Quinases de Adesão Focal/química , Proteína-Tirosina Quinases de Adesão Focal/fisiologia , Conformação Proteica , Animais , Técnicas Biossensoriais , Desenho de Fármacos , Ativação Enzimática , Inibidores Enzimáticos/uso terapêutico , Quinase 2 de Adesão Focal/antagonistas & inibidores , Quinase 2 de Adesão Focal/química , Quinase 2 de Adesão Focal/fisiologia , Proteína-Tirosina Quinases de Adesão Focal/antagonistas & inibidores , Humanos , Modelos Moleculares , Neoplasias/enzimologia , Transdução de Sinais/fisiologia
16.
Am J Physiol Cell Physiol ; 299(2): C454-63, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20519451

RESUMO

An important step in carcinoma progression is loss of cell-cell adhesion leading to increased invasion and metastasis. We show here that the protein tyrosine phosphatase, PTP-PEST, is a critical regulator of cell-cell junction integrity and epithelial cell motility. Using colon carcinoma cells, we show that the expression level of PTP-PEST regulates cell motility. Either transient small interfering RNA or stable short hairpin RNA knockdown of PTP-PEST enhances haptotactic and chemotactic migration of KM12C colon carcinoma cells. Furthermore, KM12C cells with stably knocked down PTP-PEST exhibit a mesenchymal-like phenotype with prominent membrane ruffles and lamellae. In contrast, ectopic expression of PTP-PEST in KM20 or DLD-1 cells, which lack detectable endogenous PTP-PEST expression, suppresses haptotactic migration. Importantly, we find that PTP-PEST localizes in adherens junctions. Concomitant with enhanced motility, stable knockdown of PTP-PEST causes a disruption of cell-cell junctions. These effects are due to a defect in junctional assembly and not to a loss of E-cadherin expression. Adherens junction assembly is impaired following calcium switch in KM12C cells with stably knocked down PTP-PEST and is accompanied by an increase in the activity of Rac1 and a suppression of RhoA activity in response to cadherin engagement. Taken together, these results suggest that PTP-PEST functions as a suppressor of epithelial cell motility by controlling Rho GTPase activity and the assembly of adherens junctions.


Assuntos
Junções Aderentes/fisiologia , Inibição de Migração Celular/fisiologia , Movimento Celular/fisiologia , Neoplasias do Colo/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 12/fisiologia , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Proteínas rho de Ligação ao GTP/metabolismo , Junções Aderentes/enzimologia , Junções Aderentes/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Neoplasias do Colo/enzimologia , Neoplasias do Colo/patologia , Ativação Enzimática/fisiologia , Células HCT116 , Humanos , Ratos
18.
J Clin Invest ; 120(5): 1515-23, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20389021

RESUMO

Chronic stress is associated with hormonal changes that are known to affect multiple systems, including the immune and endocrine systems, but the effects of stress on cancer growth and progression are not fully understood. Here, we demonstrate that human ovarian cancer cells exposed to either norepinephrine or epinephrine exhibit lower levels of anoikis, the process by which cells enter apoptosis when separated from ECM and neighboring cells. In an orthotopic mouse model of human ovarian cancer, restraint stress and the associated increases in norepinephrine and epinephrine protected the tumor cells from anoikis and promoted their growth by activating focal adhesion kinase (FAK). These effects involved phosphorylation of FAKY397, which was itself associated with actin-dependent Src interaction with membrane-associated FAK. Importantly, in human ovarian cancer patients, behavioral states related to greater adrenergic activity were associated with higher levels of pFAKY397, which was in turn linked to substantially accelerated mortality. These data suggest that FAK modulation by stress hormones, especially norepinephrine and epinephrine, can contribute to tumor progression in patients with ovarian cancer and may point to potential new therapeutic targets for cancer management.


Assuntos
Adrenérgicos/metabolismo , Anoikis , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Neoplasias Ovarianas/metabolismo , Actinas/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Epinefrina/metabolismo , Feminino , Humanos , Camundongos , Camundongos Nus , Norepinefrina/metabolismo , Fosforilação
19.
J Cell Sci ; 123(Pt 7): 1007-13, 2010 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-20332118

RESUMO

Focal adhesion kinase (FAK) and proline-rich tyrosine kinase 2 (Pyk2) are related tyrosine kinases that have important cellular functions, primarily through regulation of the cytoskeleton. Recent studies have identified multiple molecular mechanisms that regulate cytoskeletal responses, and have provided important and exciting insights into how FAK and Pyk2 control cellular processes such as cell migration. Equally exciting are reports of novel and originally unanticipated functions of these kinases, providing the groundwork for future avenues of investigation. This Commentary summarizes some of these recent discoveries that are relevant to the control of biological responses of the cell.


Assuntos
Movimento Celular , Citoesqueleto , Quinase 1 de Adesão Focal/metabolismo , Animais , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Transdução de Sinais , Quinases Associadas a rho/metabolismo
20.
J Cell Physiol ; 220(2): 382-93, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19350555

RESUMO

PTP-PEST is involved in the regulation of sealing ring formation in osteoclasts. In this article, we have shown a regulatory role for PTP-PEST on dephosphorylation of c-Src at Y527 and phosphorylation at Y418 in the catalytic site. Activation of Src in osteoclasts by over-expression of PTP-PEST resulted in the phosphorylation of cortactin at Y421 and WASP at Y294. Also enhanced as a result, is the interaction of Src, cortactin, and Arp2 with WASP. Moreover, the number of osteoclasts displaying sealing ring and bone resorbing activity was increased in response to PTP-PEST over-expression as compared with control osteoclasts. Cells expressing constitutively active-Src (527YDeltaF) simulate the effects mediated by PTP-PEST. Treatment of osteoclasts with a bisphosphonate alendronate or a potent PTP inhibitor PAO decreased the activity and phosphorylation of Src at Y418 due to reduced dephosphorylation state at Y527. Therefore, Src-mediated phosphorylation of cortactin and WASP as well as the formation of WASP.cortactin.Arp2 complex and sealing ring were reduced in these osteoclasts. Similar effects were observed in osteoclasts treated with an Src inhibitor PP2. We have shown that bisphosphonates could modulate the function of osteoclasts by inhibiting downstream signaling mediated by PTP-PEST/Src, in addition to its effect on the inhibition of the post-translational modification of small GTP-binding proteins such as Rab, Rho, and Rac as shown by others. The promising effects of the inhibitors PP2 and PAO on osteoclast function suggest a therapeutic approach for patients with bone metastases and osteoporosis as an alternative to bisphosphonates.


Assuntos
Difosfonatos/farmacologia , Ativação Enzimática/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteoclastos/enzimologia , Proteína Tirosina Fosfatase não Receptora Tipo 12/metabolismo , Proteínas Tirosina Fosfatases/antagonistas & inibidores , Quinases da Família src/metabolismo , Proteína 2 Relacionada a Actina/metabolismo , Alendronato/farmacologia , Animais , Conservadores da Densidade Óssea/farmacologia , Cortactina/genética , Cortactina/metabolismo , Ativação Enzimática/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Osteoclastos/citologia , Fosforilação , Proteína Tirosina Fosfatase não Receptora Tipo 12/genética , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Tirosina/metabolismo , Proteína da Síndrome de Wiskott-Aldrich/genética , Proteína da Síndrome de Wiskott-Aldrich/metabolismo , Quinases da Família src/antagonistas & inibidores , Quinases da Família src/genética
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