Structural and functional Alterations of FLT3 in Acute Myeloid Leukemia

Hematopoiesis is highly regulated through cytokine-induced stimulation of multiple signal transduction pathways in order to mediate appropriate differentiation and proliferation of specific progenitor populations. Ligand-induced stimulation of the FMS-like tyrosine kinase 3 (FLT3) leads to activation of multiple downstream effector pathways resulting in differentiation and proliferation of specific progenitor cell populations. Genomic alterations of the FLT3 gene leads to autonomous receptor activation, dysregulation of FLT3 signal transduction pathways, contributes to myeloid pathogenesis, and have been linked to response to therapy and clinical outcome. Exploring the mechanisms by which these FLT3 alterations lead to dysregulated proliferation would provide a better understanding of the molecular pathogenesis of AML and may provide insights into potential therapeutic interventions

Bortezomib is significantly beneficial for de novo pediatric AML patients with low phosphorylation of the NF-κB subunit RelA

Purpose: The addition of the proteasome inhibitor (PI) bortezomib to standard chemotherapy (ADE: cytarabine [Ara-C], daunorubicin, and etoposide) did not improve overall outcome of pediatric AML patients in the Children's Oncology Group AAML1031 phase 3 randomized clinical trial (AAML1031). Bortezomib prevents protein degradation, including RelA via the intracellular NF-kB pathway. In this study, we hypothesized that subgroups of pediatric AML patients benefitting from standard therapy plus bortezomib (ADEB) could be identified based on pre-treatment RelA expression and phosphorylation status. Experimental design: RelA-total and phosphorylation at serine 536 (RelA-pSer536) were measured in 483 patient samples using reverse phase protein array technology. Results: In ADEB-treated patients, low-RelA-pSer536 was favorably prognostic when compared to high-RelA-pSer536 (3-yr overall survival (OS): 81% vs. 68%, p = 0.032; relapse risk (RR): 30% vs. 49%, p = 0.004). Among low-RelA-pSer536 patients, RR significantly decreased with ADEB compared to ADE (RR: 30% vs. 44%, p = 0.035). Correlation between RelA-pSer536 and 295 other assayed proteins identified a strong correlation with HSF1-pSer326, another protein previously identified as modifying ADEB response. The combination of low-RelA-pSer536 and low-HSF1-pSer326 was a significant predictor of ADEB response (3-yr OS: 86% vs. 67%, p = 0.013). Conclusion and clinical relevance: Bortezomib may improve clinical outcome in a subgroup of AML patients identified by low-RelA-pSer536 and low-HSF1-pSer326

Heat Shock Factor 1 (HSF1-pSer326) Predicts Response to Bortezomib-Containing Chemotherapy in Pediatric AML:A COG Study

Bortezomib (BTZ) was recently evaluated in a randomized Phase 3 clinical trial which compared standard chemotherapy (cytarabine, daunorubicin, etoposide; ADE) to standard therapy with BTZ (ADEB) for de novo pediatric acute myeloid leukemia. While the study concluded that BTZ did not improve outcome overall, we examined patient subgroups benefitting from BTZ-containing chemotherapy using proteomic analyses. The proteasome inhibitor BTZ disrupts protein homeostasis and activates cytoprotective heat shock responses. We measured total heat shock factor 1 (HSF1) and phosphorylated HSF1 (HSF1-pSer326) in leukemic cells from 483 pediatric patients using Reverse Phase Protein Arrays. HSF1-pSer326 phosphorylation was significantly lower in pediatric AML compared to CD34+ non-malignant cells. We identified a strong correlation between HSF1-pSer326 expression and BTZ sensitivity. BTZ significantly improved outcome of patients with low-HSF1-pSer326 with a 5-year event-free survival of 44% (ADE) vs. 67% for low-HSF1-pSer326 treated with ADEB (P=0.019). To determine the effect of HSF1 expression on BTZ potency in vitro, cell viability with HSF1 gene variants that mimicked phosphorylated (S326A) and non-phosphorylated (S326E) HSF1-pSer326 were examined. Those with increased HSF1 phosphorylation showed clear resistance to BTZ vs. those with wild type or reduced HSF1-phosphorylation. We hypothesize that HSF1-pSer326 expression could identify patients that benefit from BTZ-containing chemotherapy

Clinical relevance of proteomic profiling in de novo pediatric acute myeloid leukemia:a Children’s Oncology Group study

Pediatric acute myeloid leukemia (AML) remains a fatal disease for at least 30% of patients, stressing the need for improved therapies and better risk stratification. As proteins are the unifying feature of (epi)genetic and environmental alterations, and are often targeted by novel chemotherapeutic agents, we studied the proteomic landscape of pediatric AML. Protein expression and activation levels were measured in 500 bulk leukemic patients’ samples and 30 control CD34(+) cell samples, using reverse phase protein arrays with 296 strictly validated antibodies. The multistep MetaGalaxy analysis methodology was applied and identified nine protein expression signatures (PrSIG), based on strong recurrent protein expression patterns. PrSIG were associated with cytogenetics and mutational state, and with favorable or unfavorable prognosis. Analysis based on treatment (i.e., ADE vs. ADE plus bortezomib) identified three PrSIG that did better with ADE plus bortezomib than with ADE alone. When PrSIG were studied in the context of cytogenetic risk groups, PrSIG were independently prognostic after multivariate analysis, suggesting a potential value for proteomics in combination with current classification systems. Proteins with universally increased (n=7) or decreased (n=17) expression were observed across PrSIG. Certain proteins significantly differentially expressed from normal could be identified, forming a hypothetical platform for personalized medicine

Prognostic impact of t(16;21)(p11;q22) and t(16;21)(q24;q22) in pediatric AML: A retrospective study by the I-BFM study group

To study the prognostic relevance of rare genetic aberrations in acute myeloid leukemia (AML), such as t(16:21), international collaboration is required. Two different types of t(16:21) translocations can be distinguished: t(16:21)(p11;q22), resulting in the FUS-ERG fusion gene; and t(16:21)(q24;q22), resulting in RUNX1-core binding factor (CBFA2T3). We collected data on clinical and biological characteristics of 54 pediatric AML cases with t(16:21) rearrangements from 14 international collaborative study groups participating in the international Berlin-Frankfurt-Miinster (I-BFM) AML study group. The AML-BFM cohort diagnosed between 1997 and 2013 was used as a reference cohort. RUNX1-CBFA2T3 (n = 23) had significantly lower median white blood cell count (12.5 x 10(9)/L, P = .03) compared with the reference cohort. FUS-ERG rearranged AML (n = 31) had no predominant French-American-British (FAB) type, whereas 76% of RUNX1-CBFA2T3 had an M1/M2 FAB type (M1, M2), significantly different from the reference cohort (P = .004). Four-year event-free survival (EFS) of patients with FUS-ERG was 7% (standard error [SE] = 5%), significantly lower compared with the reference cohort (51%, SE = 1%, P < .001). Four-year EFS of RUNX1-CBFA2T3 was 77% (SE = 8%, P = .06), significantly higher compared with the reference cohort. Cumulative incidence of relapse was 74% (SE = 8%) in FUS-ERG, 0% (SE = 0%) in RUNX1-CBFA2T3, compared with 32% (SE = 1%) in the reference cohort (P < .001). Multivariate analysis identified both FUS-ERG and RUNX1-CBFA2T3 as independent risk factors with hazard ratios of 1.9 (P < .0001) and 0.3 (P = .025), respectively. These results describe 2 clinically relevant distinct subtypes of pediatric AML. Similarly to other core-binding factor AMLs, patients with RUNX1-CBFA2T3 rearranged AML may benefit from stratification in the standard risk treatment, whereas patients with FUS-ERG rearranged AML should be considered high-risk

AML risk stratification models utilizing ELN-2017 guidelines and additional prognostic factors: a SWOG report.

Background: The recently updated European LeukemiaNet risk stratification guidelines combine cytogenetic abnormalities and genetic mutations to provide the means to triage patients with acute myeloid leukemia for optimal therapies. Despite the identification of many prognostic factors, relatively few have made their way into clinical practice. Methods: In order to assess and improve the performance of the European LeukemiaNet guidelines, we developed novel prognostic models using the biomarkers from the guidelines, age, performance status and select transcript biomarkers. The models were developed separately for mononuclear cells and viable leukemic blasts from previously untreated acute myeloid leukemia patients (discovery cohort, Results: Models using European LeukemiaNet guidelines were significantly associated with clinical outcomes and, therefore, utilized as a baseline for comparisons. Models incorporating age and expression of select transcripts with biomarkers from European LeukemiaNet guidelines demonstrated higher area under the curve and C-statistics but did not show a substantial improvement in performance in the validation cohort. Subset analyses demonstrated that models using only the European LeukemiaNet guidelines were a better fit for younger patients (age \u3c 55) than for older patients. Models integrating age and European LeukemiaNet guidelines visually showed more separation between risk groups in older patients. Models excluding results for Conclusions: While European LeukemiaNet guidelines remain a critical tool for triaging patients with acute myeloid leukemia, the findings illustrate the need for additional prognostic factors, including age, to improve risk stratification

Novel mesothelin antibodies enable crystallography of the intact mesothelin ectodomain and engineering of potent, T cell-engaging bispecific therapeutics

Mesothelin is a glypiated, cell-surface glycoprotein expressed at low levels on normal mesothelium but overexpressed by many cancers. Implicated in cell adhesion and multiple signaling pathways, mesothelin’s precise biological function and overall structure remain undefined. Antibodies targeting mesothelin have been engineered into immunotoxins, antibody-drug conjugates, CAR-T cells, or bispecific T cell engagers as candidate therapeutics but most face challenges, including binding epitopes that are not optimal for selected modalities. Here we describe the isolation and characterization of a novel anti-mesothelin antibody, 1A12, including crystallographic mapping of the 1A12 epitope in relation to other antibodies (amatuximab, anetumab). 1A12 possesses uniquely favorable properties, including a membrane-proximal epitope, and enabled structure determination of the complete mesothelin ectodomain. We incorporated 1A12 into two different bispecific T cell engaging architectures with various anti-CD3 co-targeting elements as candidate therapeutics, demonstrating in vitro functionality and potency

um cuidado especializado do enfermeiro obstetra

Observa-se, hoje em dia, que algumas práticas na maternidade tendem a ignorar as preferências das mulheres em trabalho de parto, uniformizando os cuidados com prejuízo para o bem-estar e a qualidade de vida das famílias. As práticas em Obstetrícia têm vindo a tornar-se cada vez mais repletas de intervenção, focando-se apenas nos resultados físicos (mortalidade e morbilidade) e descurando as vivências das parturientes e família, assim como as consequências psicossociais de um parto traumático. O presente Relatório de Estágio pretende refletir os cuidados em maternidade na perspetiva EEESMOG, que se visa holística, centrada no cliente e baseada na evidência. Da mesma forma, espelha as aprendizagens efetuadas em contexto do Estágio com Relatório inserido no 6º CMESMO da ESEL. Foram escolhidos como referenciais teóricos norteadores os modelos de Nola Pender – Modelo de Promoção da Saúde, e a Teoria de Empowerment em Saúde de Nelma Shearer. Foi também realizada uma Revisão Sistemática da Literatura que visou responder à seguinte questão de investigação: “Quais os cuidados do EEESMOG promotores do empowerment das mulheres direcionado para uma tomada de decisão informada relativa ao trabalho de parto?”. Adicionalmente, foi efetuado um registo da interação durante a prestação de cuidados no decorrer do estágio, sobre os quais foi efetuada uma reflexão e confrontação com os resultados da RSL. Concluiu-se que os cuidados que o EEESMOG presta que são promotores de uma tomada de decisão informada para o trabalho de parto se inserem dentro de três grandes temas, nomeadamente Competências da esfera relacional, Competências da esfera da prática clínica e Competências da esfera científica, com especial referência para os cuidados que se relacionam com o Estabelecimento de Relação Terapêutica, a Educação para a Saúde, o Cuidado da Mulher em trabalho de parto, a Promoção do exercício do Consentimento Informado e a Prática baseada na Evidência