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1.
Int J Cancer ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39005114

RESUMO

Little is known about the efficacy of COVID-19 vaccines during acute lymphoblastic leukemia therapy (ALL); data for COVID-19 vaccine immune responses in pediatric leukemia remain sparse. We conducted a single center study of patients aged 5-25 years undergoing ALL chemotherapy who received COVID-19 vaccination. Twenty-one patients were enrolled; efficacy was evaluable in 20. Twenty were vaccinated while receiving chemotherapy. Twenty received the BNT162b2 mRNA vaccine. Spike reactive antibodies (S-IgG) and/or T-cells (SRT) were detected in 16 of 20 (80%) vaccinated patients; 13 (65%) and 9 (45%) were positive for S-IgG and SRT, respectively. Six (30%) showed both spike reactive B and T-cell responses. Eleven of the 13 with S-IgG positivity were negative for anti-Nucleocapsid IgG, an antibody profile consistent with a vaccine induced immune response. All 13S-IgG+ patients showed neutralizing antibodies. SRT included CD4+ (7) and CD8+ (6) T-cells; both CD4+ and CD8+ SRT were seen in 4. SRT were multifunctional (producing multiple cytokines) in most patients (8 of 9); 4 showed SRT with triple cytokine and B-cell co-stimulatory responses, indicating a multimodal adaptive immune response. Immune responses were seen among patients vaccinated in the settings of lymphopenia (6 of 12) intensive chemotherapy (3 of 4), and Peg allergy (6 of 8). Sequencing revealed public CD4+ and CD8+ TCR sequences reactive to epitopes across the spike protein. In conclusion, COVID-19 vaccination induced B and/or T-cell responses in a majority of children and young adults undergoing ALL chemotherapy.

2.
Int J Cancer ; 151(11): 1913-1924, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35793239

RESUMO

Pediatric oncology patients are at risk for poor outcomes with respiratory viral infections. Outcome data for COVID-19 in children and young adults with cancer are needed; data are sparse for obese/overweight and adolescent and young adult subgroups. We conducted a single center cohort study of COVID-19 outcomes in patients younger than 25 years with cancer. Candidate hospitalization risk factors were analyzed via univariable and multivariable analyses. Eighty-seven patients with cancer and COVID-19 were identified. Most were Hispanic/Latinx (n = 63, 72%). Forty-two (48%) were overweight/obese. Anticancer therapy included chemotherapy only (n = 64, 74%), chimeric antigen receptor T-cells (CAR-T, n = 7), hematopoietic stem cell transplantation (HSCT, n = 12), or CAR-T and HSCT (n = 4). There was no COVID-19 related mortality. Twenty-six patients (30%) required COVID-19 related hospitalization; 4 required multiple hospitalizations. Nine (10%) had severe/critical infection; 6 needed intensive care. COVID-19 resulted in anticancer therapy delays in 22 (34%) of 64 patients on active therapy (median delay = 14 days). Factors associated with hospitalization included steroids within 2 weeks prior to infection, lymphopenia, previous significant non-COVID infection, and low COVID-19 PCR cycle threshold value. CAR-T recipients with B-cell aplasia tended to have severe/critical infection (3 of 7 patients). A COVID-19 antibody response was detected in 14 of 32 patients (44%). A substantial proportion of COVID-19 infected children and young adults with cancer require inpatient management; morbidity may be high in B-cell immunodeficiency. However, a majority of patients can be taken through chemotherapy without prolonged therapy delays. Viral load is a potential outcome predictor in COVID-19 in pediatric cancer.


Assuntos
COVID-19 , Transplante de Células-Tronco Hematopoéticas , Neoplasias , Receptores de Antígenos Quiméricos , Adolescente , Criança , Estudos de Coortes , Humanos , Neoplasias/complicações , Neoplasias/terapia , Obesidade , Sobrepeso , Adulto Jovem
3.
J Am Chem Soc ; 141(39): 15700-15709, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31497954

RESUMO

Controlling which particular members of a large protein family are targeted by a drug is key to achieving a desired therapeutic response. In this study, we report a rational data-driven strategy for achieving restricted polypharmacology in the design of antitumor agents selectively targeting the TYRO3, AXL, and MERTK (TAM) family tyrosine kinases. Our computational approach, based on the concept of fragments in structural environments (FRASE), distills relevant chemical information from structural and chemogenomic databases to assemble a three-dimensional inhibitor structure directly in the protein pocket. Target engagement by the inhibitors designed led to disruption of oncogenic phenotypes as demonstrated in enzymatic assays and in a panel of cancer cell lines, including acute lymphoblastic and myeloid leukemia (ALL/AML) and nonsmall cell lung cancer (NSCLC). Structural rationale underlying the approach was corroborated by X-ray crystallography. The lead compound demonstrated potent target inhibition in a pharmacodynamic study in leukemic mice.


Assuntos
Antineoplásicos/química , Receptores Proteína Tirosina Quinases/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Estrutura Molecular , Neoplasias Experimentais
4.
BMC Cancer ; 18(1): 1129, 2018 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-30445933

RESUMO

BACKGROUND: Interactions between the protein synthesis inhibitor homoharringtonine (HHT) and the proteasome inhibitor bortezomib were investigated in DLBCL and mantle cell lymphoma cells (MCL). METHODS: Various DLBCL and MCL cells were exposed to HHT and bortezomib alone or together after which apoptosis and signaling pathway perturbations were monitored by flow cytometry and Western blot analysis. Xenograft mouse models were used to assess tumor growth and animal survival. RESULTS: HHT and bortezomib co-administration synergistically induced apoptosis in GC-, ABC- and double-hit DLBCL cells. Similar interactions were observed in MCL cells and in primary lymphoma cells. HHT/bortezomib co-administration diminished binding of MCL-1 to both BAK and NOXA. Knock-down of NOXA significantly diminished lethality whereas MCL-1 knock-down or ectopic NOXA expression increased cell death. Notably, HHT/bortezomib lethality was dramatically reduced in BAK knockout or knockdown cells. Finally, HHT/bortezomib co-administration significantly improved survival compared to single agents in GC- and ABC- xenograft models while exhibiting little toxicity. CONCLUSIONS: These findings indicate that HHT and bortezomib cooperate to kill DLBCL and MCL cells through a process involving MCL-1 down-regulation, NOXA up-regulation, and BAK activation. They also suggest that a strategy combining HHT with bortezomib warrants attention in DLBCL and MCL.


Assuntos
Bortezomib/farmacologia , Mepesuccinato de Omacetaxina/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma de Célula do Manto/tratamento farmacológico , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Sinergismo Farmacológico , Humanos , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma de Célula do Manto/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Inibidores de Proteassoma/farmacologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
5.
ED Manag ; 29(4): 44-7, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-29160985

RESUMO

With President Trump and congressional Republicans promising to repeal or replace parts of the entirety of the Affordable Care Act (ACA), emergency medicine stakeholders are making sure lawmakers know what provisions in the law must remain intact, and what new reforms are needed. They also are urging emergency medicine clinicians to stay informed on the issues, and to advocate for their interests. The American College of Emergency Physicians (ACEP) wants to ensure that emergency services remain essential covered benefits, and that freestanding EDs and other emerging healthcare delivery models are supported. Although ACEP calls on lawmakers to preserve Medicaid, Medicare, and the Children's Health Insurance Program, the organization is less than satisfied with the insurance products offered on the ACA exchanges. The organization wants lawmakers to address both the affordability and transparency of coverage options. The Emergency Nurses Association calls for an expanded role for advanced practice registered nurses in both primary and emergency care, and it wants more action to improve access to mental healthcare services.


Assuntos
Serviço Hospitalar de Emergência/economia , Reforma dos Serviços de Saúde , Prioridades em Saúde , Cobertura do Seguro/economia , Cobertura do Seguro/legislação & jurisprudência , Patient Protection and Affordable Care Act , Humanos , Profissionais de Enfermagem , Papel do Profissional de Enfermagem , Estados Unidos , Recursos Humanos
7.
Haematologica ; 100(12): 1553-63, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26452980

RESUMO

Effects of concurrent inhibition of mTORC1/2 and Bcl-2/Bcl-xL in human acute myeloid leukemia cells were examined. Tetracycline-inducible Bcl-2/Bcl-xL dual knockdown markedly sensitized acute myeloid leukemia cells to the dual TORC1/2 inhibitor INK128 in vitro as well as in vivo. Moreover, INK128 co-administered with the Bcl-2/xL antagonist ABT-737 sharply induced cell death in multiple acute myeloid leukemia cell lines, including TKI-resistant FLT3-ITD mutants and primary acute myeloid leukemia blasts carrying various genetic aberrations e.g., FLT3, IDH2, NPM1, and Kras, while exerting minimal toxicity toward normal hematopoietic CD34(+) cells. Combined treatment was particularly active against CD34(+)/CD38(-)/CD123(+) primitive leukemic progenitor cells. The INK128/ABT-737 regimen was also effective in the presence of a protective stromal microenvironment. Notably, INK128 was more potent than the TORC1 inhibitor rapamycin in down-regulating Mcl-1, diminishing AKT and 4EBP1 phosphorylation, and potentiating ABT-737 activity. Mcl-1 ectopic expression dramatically attenuated INK128/ABT-737 lethality, indicating an important functional role for Mcl-1 down-regulation in INK128/ABT-737 actions. Immunoprecipitation analysis revealed that combined treatment markedly diminished Bax, Bak, and Bim binding to all major anti-apoptotic Bcl-2 members (Bcl-2/Bcl-xL/Mcl-1), while Bax/Bak knockdown reduced cell death. Finally, INK128/ABT-737 co-administration sharply attenuated leukemia growth and significantly prolonged survival in a systemic acute myeloid leukemia xenograft model. Analysis of subcutaneous acute myeloid leukemia-derived tumors revealed significant decrease in 4EBP1 phosphorylation and Mcl-1 protein level, consistent with results obtained in vitro. These findings demonstrate that co-administration of dual mTORC1/mTORC2 inhibitors and BH3-mimetics exhibits potent anti-leukemic activity in vitro and in vivo, arguing that this strategy warrants attention in acute myeloid leukemia.


Assuntos
Benzoxazóis/farmacologia , Compostos de Bifenilo/farmacologia , Regulação para Baixo/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Complexos Multiproteicos/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Nitrofenóis/farmacologia , Proteínas Proto-Oncogênicas c-akt/biossíntese , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Pirimidinas/farmacologia , Sulfonamidas/farmacologia , Serina-Treonina Quinases TOR/antagonistas & inibidores , Proteína bcl-X/antagonistas & inibidores , Animais , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Alvo Mecanístico do Complexo 1 de Rapamicina , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Complexos Multiproteicos/metabolismo , Nucleofosmina , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Células U937 , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína bcl-X/metabolismo
8.
J Learn Disabil ; : 222194241249958, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712805

RESUMO

High-level literacy skills are required for full participation in the democratic process through voting. Consequently, adults with low-level literacy skills are at a disadvantage. This work investigated the disparity between the readability of U.S. ballot propositions for year 2022 state elections and grade level reading estimates (≤eighth grade) for adults. Educational attainment was also examined. Propositions (n = 140) from 38 states were included. Mean readability was 18 (range 7.0-64.0). Only four measures (3%) fell within range of national estimates for adult reading ability. Thirty-nine percent of adults completed high school or less, yet 74% of ballots were written well above a high school reading level. There is a discrepancy between the literacy skills of the average voter and the readability of most propositions. The findings of this study have important implications for individuals with learning disabilities. Policy changes and educational support efforts should be initiated.

9.
Neuro Oncol ; 26(2): 348-361, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-37715730

RESUMO

BACKGROUND: Recurrent brain tumors are the leading cause of cancer death in children. Indoleamine 2,3-dioxygenase (IDO) is a targetable metabolic checkpoint that, in preclinical models, inhibits anti-tumor immunity following chemotherapy. METHODS: We conducted a phase I trial (NCT02502708) of the oral IDO-pathway inhibitor indoximod in children with recurrent brain tumors or newly diagnosed diffuse intrinsic pontine glioma (DIPG). Separate dose-finding arms were performed for indoximod in combination with oral temozolomide (200 mg/m2/day x 5 days in 28-day cycles), or with palliative conformal radiation. Blood samples were collected at baseline and monthly for single-cell RNA-sequencing with paired single-cell T cell receptor sequencing. RESULTS: Eighty-one patients were treated with indoximod-based combination therapy. Median follow-up was 52 months (range 39-77 months). Maximum tolerated dose was not reached, and the pediatric dose of indoximod was determined as 19.2 mg/kg/dose, twice daily. Median overall survival was 13.3 months (n = 68, range 0.2-62.7) for all patients with recurrent disease and 14.4 months (n = 13, range 4.7-29.7) for DIPG. The subset of n = 26 patients who showed evidence of objective response (even a partial or mixed response) had over 3-fold longer median OS (25.2 months, range 5.4-61.9, p = 0.006) compared to n = 37 nonresponders (7.3 months, range 0.2-62.7). Four patients remain free of active disease longer than 36 months. Single-cell sequencing confirmed emergence of new circulating CD8 T cell clonotypes with late effector phenotype. CONCLUSIONS: Indoximod was well tolerated and could be safely combined with chemotherapy and radiation. Encouraging preliminary evidence of efficacy supports advancing to Phase II/III trials for pediatric brain tumors.


Assuntos
Neoplasias Encefálicas , Neoplasias do Tronco Encefálico , Humanos , Criança , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Temozolomida , Triptofano , Fatores Imunológicos , Imunoterapia , Neoplasias do Tronco Encefálico/patologia
10.
J Mass Spectrom Adv Clin Lab ; 27: 33-39, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36593911

RESUMO

Background: Analytical methods to measure trace and toxic elements are essential to evaluate exposure and nutritional status. A ten-element panel was developed and validated for clinical testing in whole blood. Retrospective data analysis was conducted on patient samples performed at ARUP Laboratories. Methods: A method was developed and validated to quantify ten elements in whole blood by ICP-MS. Fifty microliters of sample were extracted with 950 µL of diluent containing 1 % ammonium hydroxide, 0.1 % Triton X-100, 1.75 % EDTA along with spiked internal standards. Four calibrators were used for each element and prepared in goat blood to match the patient specimen matrix. Samples were analyzed with an Agilent 7700 ICP-MS with a Cetac MVX 7100 µL Workstation autosampler. Results: The assay was linear for all elements with inter- and intra-assay imprecision less than or equal to 11% CV at the low end of the analytical measurement range (AMR) and less than or equal to 4% CV at the upper end of the AMR for all elements. Accuracy was checked with a minimum of 40 repeat patient samples, proficiency testing samples, and matrix-matched spikes. The linear slopes for the ten elements ranged from 0.94 to 1.03 with intercepts below the AMR and R2 ranging from 0.97 to 1.00. Conclusions: The multi-element panel was developed to analyze ten elements in whole blood to unify the sample preparation and increase batch run efficiency. The improved analytical method utilized matrix-matched calibrators for accurate quantification to meet regulatory requirements. The assay was validated according to guidelines for CLIA-certified clinical laboratories and was suitable for clinical testing to assess nutritional status and toxic exposure.

11.
Semin Ophthalmol ; 38(3): 294-305, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35980308

RESUMO

PURPOSE: To determine the allegation, precipitating medical issue, and outcome of telephone triage focused malpractice litigation among ophthalmologists. METHODS: The WestLaw Edge database was reviewed using terms pertaining to ophthalmology and telemedicine. The search ranged from 4/7/30 to 1/25/22. RESULTS: Of the 510 lawsuits, 3.5% (18/510) met inclusion criteria. 94.5% (17/18) alleged delays in evaluation and/or treatment. 61.1% (11/18) alleged incorrect diagnoses, 38.9% (7/18) claimed improper discussion of risks or informed consent, and 5.6% (1/18) alleged delayed referrals. The precipitating medical issues included retinal detachment in 33.3% (6/18) of cases, post-procedure and post-trauma endophthalmitis in 33.3% (6/18) of cases, ocular trauma without endophthalmitis in 22.2% (4/18) of cases, and bilateral acute retinal necrosis and allergic reactions each accounting for 5.6% (1/18) of cases. CONCLUSION: Telephone triage creates potential malpractice litigation. Delay in in-person clinical evaluation and alleged failure to inform patients of possible irreversible vision loss may lead to potential malpractice litigation. We suggest offering the option of same day in person evaluation and informing the patient how delay may lead to irreversible vision loss.


Assuntos
Endoftalmite , Imperícia , Oftalmologia , Telemedicina , Humanos , Estados Unidos , Triagem , Telefone
12.
bioRxiv ; 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37398244

RESUMO

The acquisition of invasive properties is a prerequisite for tumor progression and metastasis. Molecular subtypes of KRAS-driven lung cancer exhibit distinct modes of invasion that likely contribute to unique growth properties and therapeutic susceptibilities. Despite this, pre-clinical discovery strategies designed to exploit invasive phenotypes are lacking. To address this, we designed an experimental system to screen for targetable signaling pathways linked to active early invasion phenotypes in the two most prominent molecular subtypes, TP53 and LKB1, of KRAS-driven lung adenocarcinoma (LUAD). By combining live-cell imaging of human bronchial epithelial cells in a 3D invasion matrix with RNA transcriptome profiling, we identified the LKB1-specific upregulation of bone morphogenetic protein 6 (BMP6). Examination of early-stage lung cancer patients confirmed upregulation of BMP6 in LKB1-mutant lung tumors. At the molecular level, we find that the canonical iron regulatory hormone Hepcidin is induced via BMP6 signaling upon LKB1 loss, where intact LKB1 kinase activity is necessary to maintain signaling homeostasis. Furthermore, pre-clinical studies in a novel Kras/Lkb1-mutant syngeneic mouse model show that potent growth suppression was achieved by inhibiting the ALK2/BMP6 signaling axis with single agents that are currently in clinical trials. We show that alterations in the iron homeostasis pathway are accompanied by simultaneous upregulation of ferroptosis protection proteins. Thus, LKB1 is sufficient to regulate both the 'gas' and 'breaks' to finely tune iron-regulated tumor progression.

14.
Lang Speech ; 65(3): 554-570, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34414829

RESUMO

This study sought to determine if the inhibitory construct of executive function (EF) and self-regulation (SR) contributes unique variance to reading comprehension (RC) beyond word recognition/decoding (WR/D) and language comprehension (LC), and if the contribution differs according to language history. Thirty-two sixth, seventh, and eighth grade students participated in this study. Seventeen students had language difficulties (LD) and fifteen students had typical language histories (LH). Participants were given a battery of RC, LC, WR/D, and inhibition (attentional control and interference) measures. Hierarchical multiple regression analyses and tests for moderation effects were used to explore the contribution of each variable to RC. Inhibition contributed significant variance to RC in addition to the variance accounted for by LC and WR/D in adolescent learners. Inhibition contributed a greater proportion of variance to RC for students with typical LH than for students with LD. Advancing the understanding of the role of inhibition in EF, SR, and RC may support early identification efforts and drive the development of interventions that effectively target RC deficits.


Assuntos
Idioma , Leitura , Adolescente , Compreensão/fisiologia , Humanos , Inibição Psicológica , Testes de Linguagem
15.
Clin Chim Acta ; 528: 84-89, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35104463

RESUMO

Repeat testing is routinely required by regulatory bodies as a measure to rule out contamination in trace elements and heavy metal analysis, especially when the initial analysis result is outside the reference interval. However, its clinical utilities in detecting analytical measurement outliers have not been systematically evaluated in different clinical testing scenarios. In this study, we present an extensive evaluation of repeat testing and its comparison with the initial analysis in four serum and plasma trace element assays performed by inductively coupled plasma mass spectrometry. We demonstrate that the patient population distributions for these elements differ significantly from the reference interval established by healthy individuals. Accordingly, a significant proportion of the patient specimens would require repeat testing when using reference intervals as the threshold to perform repeat analysis. Crucially, comparison of the first analysis and repeat analysis reveals the limited utility of performing repeat measurements. The relative differences between the first and second measurements are consistent with the observed analytical imprecision of the assay and the likelihood of detecting actual analytical outliers is very low.


Assuntos
Metais Pesados , Oligoelementos , Humanos , Espectrometria de Massas/métodos , Valores de Referência , Análise Espectral
16.
BMJ Support Palliat Care ; 12(1): 58-63, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33033062

RESUMO

INTRODUCTION: Nausea and vomiting are common symptoms for patients with advanced cancer. While there is evidence for acupuncture point stimulation for treatment of these symptoms for patients having anticancer treatment, there is little for when they are not related to such treatment. OBJECTIVE: To determine whether acupressure at the pericardium 6 site can help in the treatment of nausea and vomiting suffered by palliative care patients with advanced cancer. MATERIALS AND METHODS: Double blind randomised controlled trial-active versus placebo acupressure wristbands. In-patients with advanced cancer in two specialist palliative care units who fitted either or both of the following criteria were approached: Nausea that was at least moderate; Vomiting daily on average for the prior 3 days. RESULTS: 57 patients were randomised to have either active or placebo acupressure wristbands. There was no difference in any of the outcome measures between the two groups: change from baseline number of vomits; Visual Analogue Scale for 'did acupressure wristbands help you to feel better?'; total number of as needed doses of antiemetic medication; need for escalation of antiemetics. CONCLUSIONS: In contrast to a previously published feasibility study, active acupressure wristbands were no better than placebo for specialist palliative care in-patients with advanced cancer and nausea and vomiting.


Assuntos
Acupressão , Antieméticos , Antieméticos/uso terapêutico , Humanos , Náusea/terapia , Cuidados Paliativos , Vômito/tratamento farmacológico
17.
EMBO J ; 26(20): 4324-34, 2007 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-17898805

RESUMO

Transcription factors with identical DNA-binding specificity often activate different genes in vivo. Yeast Ace2 and Swi5 are such activators, with targets we classify as Swi5-only, Ace2-only, or both. We define two unique regulatory modes. Ace2 and Swi5 both bind in vitro to Swi5-only genes such as HO, but only Swi5 binds and activates in vivo. In contrast, Ace2 and Swi5 both bind in vivo to Ace2-only genes, such as CTS1, but promoter-bound Swi5 fails to activate. We show that activation by Swi5 is prevented by the binding of the Forkhead factors Fkh1 and Fkh2, which recruit the Rpd3(Large) histone deacetylase complex to the CTS1 promoter. Global analysis shows that all Ace2-only genes are bound by both Ace2 and Swi5, and also by Fkh1/2. Genes normally activated by either Ace2 or Swi5 can be converted to Ace2-only genes by the insertion of Fkh-binding sites. Thus Fkh proteins, which function initially to activate SWI5 and ACE2, subsequently function as Swi5-specific antiactivators.


Assuntos
Proteínas de Ligação a DNA/química , Fatores de Transcrição Forkhead/metabolismo , Proteínas Fúngicas/química , Proteínas de Saccharomyces cerevisiae/química , Fatores de Transcrição/metabolismo , Acetilação , Ciclo Celular , Imunoprecipitação da Cromatina , DNA/química , Regulação Fúngica da Expressão Gênica , Histonas/química , Fases de Leitura Aberta , Regiões Promotoras Genéticas , Ligação Proteica , Estrutura Terciária de Proteína , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/química
18.
Commun Biol ; 4(1): 142, 2021 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-33514834

RESUMO

The genetic and metabolic heterogeneity of RAS-driven cancers has confounded therapeutic strategies in the clinic. To address this, rapid and genetically tractable animal models are needed that recapitulate the heterogeneity of RAS-driven cancers in vivo. Here, we generate a Drosophila melanogaster model of Ras/Lkb1 mutant carcinoma. We show that low-level expression of oncogenic Ras (RasLow) promotes the survival of Lkb1 mutant tissue, but results in autonomous cell cycle arrest and non-autonomous overgrowth of wild-type tissue. In contrast, high-level expression of oncogenic Ras (RasHigh) transforms Lkb1 mutant tissue resulting in lethal malignant tumors. Using simultaneous multiview light-sheet microcopy, we have characterized invasion phenotypes of Ras/Lkb1 tumors in living larvae. Our molecular analysis reveals sustained activation of the AMPK pathway in malignant Ras/Lkb1 tumors, and demonstrate the genetic and pharmacologic dependence of these tumors on CaMK-activated Ampk. We further show that LKB1 mutant human lung adenocarcinoma patients with high levels of oncogenic KRAS exhibit worse overall survival and increased AMPK activation. Our results suggest that high levels of oncogenic KRAS is a driving event in the malignant transformation of LKB1 mutant tissue, and uncovers a vulnerability that may be used to target this aggressive genetic subset of RAS-driven tumors.


Assuntos
Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Genes ras , Mutação , Neoplasias Experimentais/genética , Proteínas Quinases/genética , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/metabolismo , Adenocarcinoma de Pulmão/enzimologia , Adenocarcinoma de Pulmão/genética , Adenocarcinoma de Pulmão/mortalidade , Animais , Animais Geneticamente Modificados , Proteínas Quinases Dependentes de Cálcio-Calmodulina/metabolismo , Morte Celular , Movimento Celular , Bases de Dados Genéticas , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/embriologia , Drosophila melanogaster/enzimologia , Ativação Enzimática , Predisposição Genética para Doença , Humanos , Larva/enzimologia , Larva/genética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Invasividade Neoplásica , Neoplasias Experimentais/enzimologia , Fenótipo , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
19.
Blood Adv ; 5(19): 3776-3788, 2021 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-34464977

RESUMO

Interactions between the inhibitor of apoptosis protein antagonist LCL161 and the histone deacetylase inhibitor panobinostat (LBH589) were examined in human multiple myeloma (MM) cells. LCL161 and panobinostat interacted synergistically to induce apoptosis in diverse MM cell lines, including those resistant to bortezomib (PS-R). Similar interactions were observed with other histone deacetylase inhibitors (MS-275) or inhibitors of apoptosis protein antagonists (birinapant). These events were associated with downregulation of the noncanonical (but not the canonical) NF-κB pathway and activation of the extrinsic, caspase-8-related apoptotic cascade. Coexposure of MM cells to LCL161/LBH589 induced TRAF3 upregulation and led to TRAF2 and NIK downregulation, diminished expression of BCL-XL, and induction of γH2A.X. Ectopic expression of TRAF2, NIK, or BCL-XL, or short hairpin RNA TRAF3 knock-down, significantly reduced LCL161/LBH589 lethality, as did ectopic expression of dominant-negative FADD. Stromal/microenvironmental factors failed to diminish LCL161/LBH589-induced cell death. The LCL161/LBH589 regimen significantly increased cell killing in primary CD138+ cells (N = 31) and was particularly effective in diminishing the primitive progenitor cell-enriched CD138-/19+/20+/27+ population (N = 23) but was nontoxic to normal CD34+ cells. Finally, combined LCL161/LBH589 treatment significantly increased survival compared with single-agent treatment in an immunocompetent 5TGM1 murine MM model. Together, these findings argue that LCL161 interacts synergistically with LBH589 in MM cells through a process involving inactivation of the noncanonical NF-κB pathway and activation of the extrinsic apoptotic pathway, upregulation of TRAF3, and downregulation of TRAF2/BCL-XL. Notably, this regimen overcomes various forms of resistance, is active against primary MM cells, and displays significant in vivo activity. This strategy warrants further consideration in MM.


Assuntos
Inibidores de Histona Desacetilases , Mieloma Múltiplo , Animais , Caspase 8/genética , Linhagem Celular Tumoral , Inibidores de Histona Desacetilases/farmacologia , Humanos , Camundongos , Mieloma Múltiplo/tratamento farmacológico , NF-kappa B
20.
Clin Biochem ; 82: 90-98, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32407718

RESUMO

BACKGROUND: Laboratory testing for trace and toxic elements is important to diagnose metal toxicity and nutritional deficiency. There are several essential elements that are necessary for biological function and non-essential elements that can pose risk from exposure. Both essential and nonessential elements can be toxic if concentrations exceed a certain threshold. METHODS: An aliquot of serum was diluted in a diluent solution, which contained iridium (Ir) as the internal standard, gold (Au), 0.05% Triton X-100, and 1% nitric acid (HNO3). The diluted specimen was aspirated into an inductively coupled plasma-mass spectrometer for quantitative elemental analysis of chromium (Cr), cobalt (Co), copper (Cu), manganese (Mn), nickel (Ni), selenium (Se) and zinc (Zn). The sample was introduced into the instrument spray chamber to form aerosol droplets, then atomized and ionized in argon plasma. The ions exited the plasma, passed through the interface of the instrument, then arrived at the entrance of the collision cell where helium gas was introduced to remove polyatomic interferences by kinetic energy discrimination (KED). After exiting the collision cell, the ions were filtered by a quadrupole mass spectrometer. RESULTS: The analytical measurement range was determined specifically for each element. Imprecision was <20% CV for the lowest limit of quantification for each element and accuracy was within ±15%. CONCLUSIONS: This method was validated for the quantification of seven elements in serum to assess nutritional deficiency and toxicity. The multi-element panel by ICP-MS met the validation criteria for biological monitoring of trace and toxic elements in patient specimens.


Assuntos
Intoxicação por Metais Pesados/sangue , Desnutrição/sangue , Espectrometria de Massas/métodos , Metais Pesados/sangue , Selênio/sangue , Espectrofotometria Atômica/métodos , Oligoelementos/sangue , Confiabilidade dos Dados , Intoxicação por Metais Pesados/diagnóstico , Humanos , Desnutrição/diagnóstico , Estudos Retrospectivos , Sensibilidade e Especificidade
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