RESUMEN
BACKGROUND: The insulin-like growth factor-1 (IGF-1) signaling pathway plays an important role in the pathology of Ewing sarcoma (ES). Retrospective studies have suggested that levels of IGF-1 and IGF binding protein 3 (IGFBP-3) are correlated with the outcome of patients with ES. METHODS: The IGF-1 signaling pathway was investigated prospectively in 269 patients who had localized, previously untreated ES. Serum samples were obtained at diagnosis, and concentrations of IGF-1 and IGFBP-3 were determined by enzyme-linked immunosorbent assays. In addition, immunohistochemistry (IHC) was performed to assay for phosphorylated p70S6 kinase, protein kinase B (Akt), and forkhead box protein O1 (FOXO1) and to determine the presence of protein tyrosine phosphatase-L1 (PTPL1). IHC findings along with IGF-1 and IGFBP-3 concentrations were correlated with age, tumor location, sex, event-free survival, and overall survival. RESULTS: Patients aged >18 years tended to have higher levels of IGF-1 (P = .10), lower levels of IGFBP-3 (P = .16), and decreased IGFBP-3:IGF-1 ratios (P = .01). No correlations were observed between sex, tumor location, or outcomes and concentrations of IGF-1 or IGFBP-3. Phosphorylation of p70S6 kinase, Akt, and FOXO1 was detected in the majority of patient tissues but was not associated with age, sex, or tumor location. PTPL1 was present in >80% of tumors and also was not correlated with age, sex, or tumor location. There was no difference in survival with respect to the presence of phosphorylated p70S6 kinase, phosphorylated FOXO1, phosphorylated Akt, or PTPL1. CONCLUSIONS: The baseline IGFBP-3:IGF-1 ratio was correlated with age but did not affect the outcomes of patients with ES. The authors concluded that additional investigation of the IGF-1 pathway is warranted in patients with ES, and especially in those who have received treatment with IGF-1 receptor antibody inhibitors.
Asunto(s)
Factor I del Crecimiento Similar a la Insulina/metabolismo , Sarcoma de Ewing/sangre , Adolescente , Adulto , Factores de Edad , Niño , Femenino , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Masculino , Sarcoma de Ewing/mortalidad , Transducción de SeñalRESUMEN
BACKGROUND: Formative events during training help shape professional identity and may impact well-being. This study sought to identify formative experiences during anesthesia residency and measure their perceived impact on well-being. METHODS: A 24-item survey exploring the frequency and perceived impact of formative events was developed through a rigorous process involving a literature search, consultation with medical education experts, resident focus groups, graduate interviews, and pilot testing. All 80 anesthesiology residents at Johns Hopkins University were invited to participate. We measured the frequency of event exposure and perceived impact on well-being. RESULTS: Seventy-six residents (95%) completed the survey. Event exposure rate ranged from 56.6% to 100%. Events with greatest relative impact (RI) overall included leaving work earlier than expected (RIoverall = 85.8), a patient expresses genuine gratitude (RIoverall = 80.2), identifying a faculty role model (RIoverall = 75.7), and having a patient die under my care (RIoverall = 75.6). There was no statistically significant difference on RI for positive versus negative events. The perceived impact of events on well-being varied by gender. CONCLUSIONS: This work provides clarity for residency program leaders and educators about the commonly experienced formative events that have the greatest perceived impact on resident well-being. These results may inform curricular planning and can suggest times when trainees may need attention or support. Future research should evaluate the direct impact of formative events on well-being and the success of related interventions.
RESUMEN
Although blood transfusion is a lifesaving therapy for some patients, transfusion has been named 1 of the top 5 overused procedures in US hospitals. As unnecessary transfusions only increase risk and cost without providing benefit, improving transfusion practice is an effective way of promoting high-value care. Most high-quality clinical trials supporting a restrictive transfusion strategy have been published in the past 5 to 10 years, so the value of a successful patient blood management program has only recently been recognized. We review the most recent transfusion practice guidelines and the evidence supporting these guidelines. We also discuss several medical societies' Choosing Wisely campaigns to reduce or eliminate overuse of transfusions. A blueprint is presented for developing a patient blood management program, which includes discussion of specific methods for optimizing transfusion practice.
Asunto(s)
Transfusión Sanguínea/tendencias , Auditoría Médica/métodos , Uso Excesivo de los Servicios de Salud/prevención & control , Desarrollo de Programa , Procedimientos Innecesarios/tendencias , Humanos , Estados UnidosRESUMEN
EWS-FLI1 is an oncogenic fusion protein implicated in the development of Ewing's sarcoma family tumors (ESFT). Using our previously reported lead compound 2 (YK-4-279), we designed and synthesized a focused library of analogues. The functional inhibition of the analogues was measured by an EWS-FLI1/NR0B1 reporter luciferase assay and a paired cell screening approach measuring effects on growth inhibition for human cells containing EWS-FLI1 (TC32 and TC71) and control PANC1 cell lines devoid of the oncoprotein. Our data revealed that substitution of electron donating groups at the para-position on the phenyl ring was the most favorable for inhibition of EWS-FLI1 by analogs of 2. Compound 9u (with a dimethylamino substitution) was the most active inhibitor with GI50 = 0.26 ± 0.1 µM. Further, a correlation of growth inhibition (EWS-FLI1 expressing TC32 cells) and the luciferase reporter activity was established (R(2) = 0.84). Finally, we designed and synthesized a biotinylated analogue and determined the binding affinity for recombinant EWS-FLI1 (Kd = 4.8 ± 2.6 µM).
Asunto(s)
Compuestos de Anilina/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Neoplasias Óseas/tratamiento farmacológico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Indoles/farmacología , Proteínas de Fusión Oncogénica/antagonistas & inhibidores , Proteína Proto-Oncogénica c-fli-1/antagonistas & inhibidores , Proteína EWS de Unión a ARN/antagonistas & inhibidores , Sarcoma de Ewing/tratamiento farmacológico , Compuestos de Anilina/síntesis química , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Humanos , Indoles/síntesis química , Luciferasas/metabolismo , Modelos Moleculares , Estructura Molecular , Proteínas de Fusión Oncogénica/metabolismo , Proteína Proto-Oncogénica c-fli-1/metabolismo , Proteína EWS de Unión a ARN/metabolismo , Sarcoma de Ewing/metabolismo , Sarcoma de Ewing/patología , Relación Estructura-Actividad , Células Tumorales CultivadasRESUMEN
Oncogenic fusion proteins, such as EWS-FLI1, are excellent therapeutic targets as they are only located within the tumor. However, there are currently no agents targeted toward transcription factors, which are often considered to be 'undruggable.' A considerable body of evidence is accruing that refutes this claim based upon the intrinsic disorder of transcription factors. Our previous studies show that RNA Helicase A (RHA) enhances the oncogenesis of EWS-FLI1, a putative intrinsically disordered protein. Interruption of this protein-protein complex by small molecule inhibitors validates this interaction as a unique therapeutic target. Single enantiomer activity from a chiral compound has been recognized as strong evidence for specificity in a small molecule-protein interaction. Our compound, YK-4-279, has a chiral center and can be separated into two enantiomers by chiral HPLC. We show that there is a significant difference in activity between the two enantiomers. (S)-YK-4-279 is able to disrupt binding between EWS-FLI1 and RHA in an immunoprecipitation assay and blocks the transcriptional activity of EWS-FLI1, while (R)-YK-4-279 cannot. Enantiospecific effects are also established in cytotoxicity assays and caspase assays, where up to a log-fold difference is seen between (S)-YK-4-279 and the racemic YK-4-279. Our findings indicate that only one enantiomer of our small molecule is able to specifically target a protein-protein interaction. This work is significant for its identification of a single enantiomer effect upon a protein interaction suggesting that small molecule targeting of intrinsically disordered proteins can be specific. Furthermore, proving YK-4-279 has only one functional enantiomer will be helpful in moving this compound towards clinical trials.
Asunto(s)
Indoles/farmacología , Proteínas de Fusión Oncogénica/antagonistas & inhibidores , Proteína Proto-Oncogénica c-fli-1/antagonistas & inhibidores , Proteína EWS de Unión a ARN/antagonistas & inhibidores , Sarcoma de Ewing/tratamiento farmacológico , Animales , Caspasa 3/metabolismo , Línea Celular Tumoral , Proliferación Celular , Humanos , Ratas , Ratas Sprague-Dawley , Estereoisomerismo , Factores de Transcripción/metabolismo , Activación Transcripcional , Trasplante HeterólogoRESUMEN
Ewing tumor is driven by the oncogenic EWS-FLI1 fusion protein that functions as an aberrant transcription factor. The identification of EWS-FLI1 protein partners is essential to enhance its vulnerability as a therapeutic target. We utilized phage display library screening against recombinant EWS-FLI1 protein. We identified 27 unique Ewing sarcoma binding peptides. The cytotoxicity evaluation of these peptides with in EWS-FLI1 containing cell lines yielded one potent peptide called ESAP1 (TMRGKKKRTRAN). ESAP1 binds EWS-FLI1 with 0.202 micromolar affinity as measured in surface plasmon resonance. The minimal interaction region of ESAP1 is characterized and found that the lysine residues are critical for cellular cytotoxicity. ESAP1 reduces the transcriptional activity of EWS-FLI1 as well as disrupts cell cycle kinetics in Ewing Tumor cells. These findings provide both a novel experimental probe and a potential therapeutic scaffold for Ewing Tumor.