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1.
Carcinogenesis ; 45(9): 696-707, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39051454

RESUMO

Ral-binding/interacting protein (RLIP) acts as a transporter that responds to stress and provides protection, specifically against glutathione-electrophile conjugates and xenobiotic toxins. Its increased presence in malignant cells, especially in cancer, emphasizes its crucial antiapoptotic function. This is achieved by selectively regulating the cellular levels of proapoptotic oxidized lipid byproducts. Suppressing the progression of tumors in human xenografts can be achieved by effectively inhibiting RLIP, a transporter in the mercapturic acid pathway, without involving chemotherapy. Utilizing ovarian cancer (OC) cell lines (MDAH2774, OVCAR4, and OVCAR8), we observed that agents targeting RLIP, such as RLIP antisense and RLIP antibodies, not only substantially impeded the viability of OC cells but also remarkably increased their sensitivity to carboplatin. To delve further into the cytotoxic synergy between RLIP antisense, RLIP antibodies, and carboplatin, we conducted investigations in both cell culture and xenografts of OC cells. The outcomes revealed that RLIP depletion via phosphorothioate antisense led to rapid and sustained remissions in established subcutaneous human ovary xenografts. Furthermore, RLIP inhibition by RLIP antibodies exhibited comparable efficacy to antisense and enhanced the effectiveness of carboplatin in MDAH2774 OC xenografts. These investigations underscore RLIP as a central carrier crucial for supporting the survival of cancer cells, positioning it as a suitable focus for cancer treatment.


Assuntos
Carboplatina , Neoplasias Ovarianas , Ensaios Antitumorais Modelo de Xenoenxerto , Humanos , Feminino , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/metabolismo , Animais , Carboplatina/farmacologia , Camundongos , Linhagem Celular Tumoral , Antineoplásicos/farmacologia , Camundongos Nus , Apoptose/efeitos dos fármacos , Acetilcisteína/farmacologia , Transportadores de Cassetes de Ligação de ATP , Proteínas Ativadoras de GTPase
2.
Blood ; 139(26): 3752-3770, 2022 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-35439288

RESUMO

Differentiation blockade is a hallmark of acute myeloid leukemia (AML). A strategy to overcome such a blockade is a promising approach against the disease. The lack of understanding of the underlying mechanisms hampers development of such strategies. Dysregulated ribonucleotide reductase (RNR) is considered a druggable target in proliferative cancers susceptible to deoxynucleoside triphosphate (dNTP) depletion. Herein, we report an unanticipated discovery that hyperactivating RNR enables differentiation and decreases leukemia cell growth. We integrate pharmacogenomics and metabolomics analyses to identify that pharmacologically (eg, nelarabine) or genetically upregulating RNR subunit M2 (RRM2) creates a dNTP pool imbalance and overcomes differentiation arrest. Moreover, R-loop-mediated DNA replication stress signaling is responsible for RRM2 activation by nelarabine treatment. Further aggravating dNTP imbalance by depleting the dNTP hydrolase SAM domain and HD domain-containing protein 1 (SAMHD1) enhances ablation of leukemia stem cells by RRM2 hyperactivation. Mechanistically, excessive activation of extracellular signal-regulated kinase (ERK) signaling downstream of the imbalance contributes to cellular outcomes of RNR hyperactivation. A CRISPR screen identifies a synthetic lethal interaction between loss of DUSP6, an ERK-negative regulator, and nelarabine treatment. These data demonstrate that dNTP homeostasis governs leukemia maintenance, and a combination of DUSP inhibition and nelarabine represents a therapeutic strategy.


Assuntos
Leucemia Mieloide Aguda , Ribonucleotídeo Redutases , Replicação do DNA , Homeostase , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Polifosfatos , Ribonucleotídeo Redutases/genética , Ribonucleotídeo Redutases/metabolismo
3.
J Org Chem ; 89(9): 6230-6237, 2024 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-38629386

RESUMO

A concise synthesis of pareitropone by oxidative cyclization of a phenolic nitronate is delineated. The use of TMSOTf as an additive to promote the facile formation of a strained norcaradiene intermediate provides convenient access to highly condensed multicyclic tropones in high yields. This synthesis is modular, efficient, and scalable, highlighting the synthetic utility of radical anion coupling reactions in annulation reactions. This work is discussed in the context of total syntheses of the tropoloisoquinoline alkaloids. Also included are the preparation of several congeners and a brief description of their biological activities.


Assuntos
Antineoplásicos , Humanos , Estrutura Molecular , Ciclização , Linhagem Celular Tumoral , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , Ensaios de Seleção de Medicamentos Antitumorais , Oxirredução
4.
Perfusion ; : 2676591241291944, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39383445

RESUMO

BACKGROUND: The inflammatory response to cardiopulmonary bypass (CPB) in pediatric patients remains an unresolved challenge. Sanguineous CPB prime, composed of allogenic blood products, is one potentially important stimulus. This study aims to identify specific inflammatory mediators active in sanguineous CPB prime and their impact on the inflammatory response at CPB initiation. METHODS: In a post-hoc analysis of a prospective observational cohort study (NCT05154864), where pediatric patients undergoing cardiac surgery with CPB were enrolled after informed consent, patients were grouped by CPB prime type (sanguineous vs crystalloid). Arterial samples were collected post-sternotomy as a baseline and again at CPB initiation from all patients. In the sanguineous group, CPB prime samples were also collected after buffered ultrafiltration but before CPB initiation. Luminex® measured concentrations of 24 inflammatory mediators for comparison between groups. Statistical analyses were by Mann-Whitney test and Wilcoxon signed-rank test. Data are presented as median [IQR]. RESULTS: Forty consecutive pediatric patients participated. The sanguineous group (n = 26) was younger (4.0 [0.2 - 6.0] vs 48.5 [39.0 - 69.5] months; p = 2.6 × 10-7) and smaller (4.9 [34 - 6.6] vs 17.2 [14.9 - 19.6] kg; p = 2.6 × 10-7) than the crystalloid group (n = 14). Despite this, baseline concentrations of 20 complement and cytokine concentrations were comparable between groups (p > 0.05) while four showed differences between groups (p < 0.05). The sanguineous prime contained supraphysiologic concentrations of complement mediators: C2, C3, C3a, C3b, and C5a. Correspondingly, upon CPB initiation, patients receiving sanguineous prime exhibited a significantly larger burden of C2, C3, C3b, C5, and C5a (p < 0.001) relative to the crystalloid group. Cytokine and chemokine mediators were present at trace levels in the sanguineous prime. CONCLUSIONS: Sanguineous prime contains activated complement that accelerates the inflammatory response at CPB initiation in neonates and infants. Immunomodulatory interventions targeting complement during CPB prime preparation could offer substantial benefits for these vulnerable patients.

5.
Clin Infect Dis ; 77(7): 1053-1062, 2023 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-37249079

RESUMO

BACKGROUND: Rifampin-resistant tuberculosis is a leading cause of morbidity worldwide; only one-third of persons start treatment, and outcomes are often inadequate. Several trials demonstrate 90% efficacy using an all-oral, 6-month regimen of bedaquiline, pretomanid, and linezolid (BPaL), but significant toxicity occurred using 1200-mg linezolid. After US Food and Drug Administration approval in 2019, some US clinicians rapidly implemented BPaL using an initial 600-mg linezolid dose adjusted by serum drug concentrations and clinical monitoring. METHODS: Data from US patients treated with BPaL between 14 October 2019 and 30 April 2022 were compiled and analyzed by the BPaL Implementation Group (BIG), including baseline examination and laboratory, electrocardiographic, and clinical monitoring throughout treatment and follow-up. Linezolid dosing and clinical management was provider driven, and most patients had linezolid adjusted by therapeutic drug monitoring. RESULTS: Of 70 patients starting BPaL, 2 changed to rifampin-based therapy, 68 (97.1%) completed BPaL, and 2 of the 68 (2.9%) experienced relapse after completion. Using an initial 600-mg linezolid dose daily adjusted by therapeutic drug monitoring and careful clinical and laboratory monitoring for adverse effects, supportive care, and expert consultation throughout BPaL treatment, 3 patients (4.4%) with hematologic toxicity and 4 (5.9%) with neurotoxicity required a change in linezolid dose or frequency. The median BPaL duration was 6 months. CONCLUSIONS: BPaL has transformed treatment for rifampin-resistant or intolerant tuberculosis. In this cohort, effective treatment required less than half the duration recommended in 2019 US guidelines for drug-resistant tuberculosis. Use of individualized linezolid dosing and monitoring likely enhanced safety and treatment completion. The BIG cohort demonstrates that early implementation of new tuberculosis treatments in the United States is feasible.


Assuntos
Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose , Humanos , Estados Unidos , Rifampina/efeitos adversos , Linezolida/efeitos adversos , Antituberculosos/efeitos adversos , Tuberculose/tratamento farmacológico , Diarilquinolinas/efeitos adversos , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico
6.
J Transl Med ; 21(1): 439, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37408044

RESUMO

BACKGROUND: Cardiopulmonary bypass (CPB) is associated with systemic inflammation, featuring increased levels of circulating pro-inflammatory cytokines. Intra-operative ultrafiltration extracts fluid and inflammatory factors potentially dampening inflammation-related organ dysfunction and enhancing post-operative recovery. This study aimed to define the impact of continuous subzero-balance ultrafiltration (SBUF) on circulating levels of major inflammatory mediators. METHODS: Twenty pediatric patients undergoing cardiac surgery, CPB and SBUF were prospectively enrolled. Blood samples were collected prior to CPB initiation (Pre-CPB Plasma) and immediately before weaning off CPB (End-CPB Plasma). Ultrafiltrate effluent samples were also collected at the End-CPB time-point (End-CPB Effluent). The concentrations of thirty-nine inflammatory factors were assessed and sieving coefficients were calculated. RESULTS: A profound increase in inflammatory cytokines and activated complement products were noted in plasma following CBP. Twenty-two inflammatory mediators were detected in the ultrafiltrate effluent. Novel mediators removed by ultrafiltration included cytokines IL1-Ra, IL-2, IL-12, IL-17A, IL-33, TRAIL, GM-CSF, ET-1, and the chemokines CCL2, CCL3, CCL4, CXCL1, CXCL2 and CXCL10. Mediator extraction by SBUF was significantly associated with molecular mass < 66 kDa (Chi2 statistic = 18.8, Chi2 with Yates' correction = 16.0, p < 0.0001). There was a moderate negative linear correlation between molecular mass and sieving coefficient (Spearman R = - 0.45 and p = 0.02). Notably, the anti-inflammatory cytokine IL-10 was not efficiently extracted by SBUF. CONCLUSIONS: CPB is associated with a burden of circulating inflammatory mediators, and SBUF selectively extracts twenty of these pro-inflammatory factors while preserving the key anti-inflammatory regulator IL-10. Ultrafiltration could potentially function as an immunomodulatory therapy during pediatric cardiac surgery. Trial registration ClinicalTrials.gov, NCT05154864. Registered retrospectively on December 13, 2021. https://clinicaltrials.gov/ct2/show/record/NCT05154864 .


Assuntos
Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Humanos , Criança , Ultrafiltração , Estudos Retrospectivos , Citocinas , Inflamação , Quimiocina CCL2 , Anti-Inflamatórios
7.
Clin Chem ; 69(12): 1409-1419, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37956323

RESUMO

BACKGROUND: Novel approaches that allow early diagnosis and treatment monitoring of both human immunodeficiency virus-1 (HIV-1) and tuberculosis disease (TB) are essential to improve patient outcomes. METHODS: We developed and validated an immuno-affinity liquid chromatography-tandem mass spectrometry (ILM) assay that simultaneously quantifies single peptides derived from HIV-1 p24 and Mycobacterium tuberculosis (Mtb) 10-kDa culture filtrate protein (CFP10) in trypsin-digested serum derived from cryopreserved serum archives of cohorts of adults and children with/without HIV and TB. RESULTS: ILM p24 and CFP10 results demonstrated good intra-laboratory precision and accuracy, with recovery values of 96.7% to 104.6% and 88.2% to 111.0%, total within-laboratory precision (CV) values of 5.68% to 13.25% and 10.36% to 14.92%, and good linearity (r2 > 0.99) from 1.0 to 256.0 pmol/L and 0.016 to 16.000 pmol/L, respectively. In cohorts of adults (n = 34) and children (n = 17) with HIV and/or TB, ILM detected p24 and CFP10 demonstrated 85.7% to 88.9% and 88.9% to 100.0% diagnostic sensitivity for HIV-1 and TB, with 100% specificity for both, and detected HIV-1 infection earlier than 3 commercial p24 antigen/antibody immunoassays. Finally, p24 and CFP10 values measured in longitudinal serum samples from children with HIV-1 and TB distinguished individuals who responded to TB treatment from those who failed to respond or were untreated, and who developed TB immune reconstitution inflammatory syndrome. CONCLUSIONS: Simultaneous ILM evaluation of p24 and CFP10 results may allow for early TB and HIV detection and provide valuable information on treatment response to facilitate integration of TB and HIV diagnosis and management.


Assuntos
Infecções por HIV , HIV-1 , Mycobacterium tuberculosis , Adulto , Criança , Humanos , Espectrometria de Massas em Tandem , Infecções por HIV/diagnóstico , Peptídeos , Cromatografia Líquida , Sensibilidade e Especificidade
8.
Proc Natl Acad Sci U S A ; 117(7): 3621-3626, 2020 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-32024762

RESUMO

Ten-eleven translocation (TET) family enzymes (TET1, TET2, and TET3) oxidize 5-methylcytosine (5mC) and generate 5-hydroxymethylcytosine (5hmC) marks on the genome. Each TET protein also interacts with specific binding partners and partly plays their role independent of catalytic activity. Although the basic role of TET enzymes is well established now, the molecular mechanism and specific contribution of their catalytic and noncatalytic domains remain elusive. Here, by combining in silico and biochemical screening strategy, we have identified a small molecule compound, C35, as a first-in-class TET inhibitor that specifically blocks their catalytic activities. Using this inhibitor, we explored the enzymatic function of TET proteins during somatic cell reprogramming. Interestingly, we found that C35-mediated TET inactivation increased the efficiency of somatic cell programming without affecting TET complexes. Using high-throughput mRNA sequencing, we found that by targeting 5hmC repressive marks in the promoter regions, C35-mediated TET inhibition activates the transcription of the BMP-SMAD-ID signaling pathway, which may be responsible for promoting somatic cell reprogramming. These results suggest that C35 is an important tool for inducing somatic cell reprogramming, as well as for dissecting the other biological functions of TET enzymatic activities without affecting their other nonenzymatic roles.


Assuntos
Reprogramação Celular , Proteínas de Ligação a DNA/antagonistas & inibidores , Dioxigenases/antagonistas & inibidores , Inibidores Enzimáticos/química , Proteínas Proto-Oncogênicas/antagonistas & inibidores , 5-Metilcitosina/análogos & derivados , 5-Metilcitosina/metabolismo , Domínio Catalítico , Linhagem Celular , Reprogramação Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dioxigenases/química , Dioxigenases/genética , Dioxigenases/metabolismo , Humanos , Oxigenases de Função Mista/antagonistas & inibidores , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
9.
Cardiol Young ; 33(5): 798-799, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36047010

RESUMO

A rare case of unique and previously unreported variant of transposition of great arteries with bilateral coni, ventricular septal defect, and triple-chambered left ventricle which led to an unexpected and accelerated post-natal cardiac anatomical and physiologic deviation from prenatal and immediate postnatal diagnosis altering the surgical management and patient outcome.


Assuntos
Comunicação Interventricular , Transposição dos Grandes Vasos , Humanos , Transposição dos Grandes Vasos/cirurgia , Ventrículos do Coração , Comunicação Interventricular/cirurgia , Artérias , Coração
10.
Molecules ; 28(14)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37513205

RESUMO

The regulation of bile acid pathways has become a particularly promising therapeutic strategy for a variety of metabolic disorders, cancers, and diseases. However, the hydrophobicity of bile acids has been an obstacle to clinical efficacy due to off-target effects from rapid drug absorption. In this report, we explored a novel strategy to design new structure fragments based on lithocholic acid (LCA) with improved hydrophilicity by introducing a polar "oxygen atom" into the side chain of LCA, then (i) either retaining the carboxylic acid group or replacing the carboxylic acid group with (ii) a diol group or (iii) a vinyl group. These novel fragments were evaluated using luciferase-based reporter assays and the MTS assay. Compared to LCA, the result revealed that the two lead compounds 1a-1b were well tolerated in vitro, maintaining similar potency and efficacy to LCA. The MTS assay results indicated that cell viability was not affected by dose dependence (under 25 µM). Additionally, computational model analysis demonstrated that compounds 1a-1b formed more extensive hydrogen bond networks with Takeda G protein-coupled receptor 5 (TGR5) than LCA. This strategy displayed a potential approach to explore the development of novel endogenous bile acids fragments. Further evaluation on the biological activities of the two lead compounds is ongoing.


Assuntos
Ácidos e Sais Biliares , Ácido Litocólico , Ácido Litocólico/farmacologia , Ácidos e Sais Biliares/farmacologia
11.
Hematol Oncol ; 40(3): 356-369, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35482553

RESUMO

Concurrent translocations of MYC and BCL2 lead to abnormal expression of both oncoproteins, which contribute to the aggressive clinical characteristics of double-hit lymphoma (DHL). An effective therapy for DHL remains an unmet clinical need. In this study, we showed that both Ca2+ /calmodulin-dependent protein kinase II δ (CAMKIIδ) and γ (CAMKIIγ) were highly expressed in DHL. Both isoforms of CAMKII stabilize c-Myc protein by phosphorylating it at Ser62, increase BCL2 expression, and promote DHL tumor growth. Inhibition of CAMKIIδ and CAMKIIγ by either berbamine (BBM) or one of its derivatives (PA4) led to the down regulation of c-Myc and BCL2 proteins. BBM/PA4 also exhibited anti-tumor efficacy in DHL cell lines and NSG xenograft models. Altogether, CAMKIIδ and CAMKIIγ appear to be critical for DHL tumor development and are promising therapeutic targets for DHL.


Assuntos
Linfoma de Células B , Linfoma Difuso de Grandes Células B , Proteínas Proto-Oncogênicas c-bcl-2 , Proteínas Proto-Oncogênicas c-myc , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Rearranjo Gênico , Humanos , Linfoma de Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo
12.
Perfusion ; 37(8): 785-788, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34142611

RESUMO

The use of cardiopulmonary bypass (CPB) can be associated with significant hemodilution, coagulopathy and a systemic inflammatory response for infants and children undergoing cardiac surgery. Intra-operative ultrafiltration has been used for decades to ameliorate these harmful effects. The novel combination of a continuous and non-continuous form of ultrafiltration, Subzero Balance Simple Modified Ultrafiltration (SBUF-SMUF) here described, seeks to enhance recovery from pediatric cardiac surgery and CPB.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Ponte Cardiopulmonar , Lactente , Humanos , Criança , Ponte Cardiopulmonar/métodos , Ultrafiltração/métodos , Resultado do Tratamento , Procedimentos Cirúrgicos Cardíacos/métodos , Hemodiluição
13.
Can Assoc Radiol J ; 73(1): 38-48, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34227429

RESUMO

PURPOSE: Quantify resident caseload during call and determine if there are consistent differences in call volumes for individuals or resident subgroups. METHODS: Accession codes for after-hours computed tomography (CT) cases dictated by residents between July 1, 2012 and January 9, 2017 were reviewed. Case volumes by patient visits and body regions scanned were determined and categorized according to time period, year, and individual resident. Mean shift Relative Value Units (RVUs) were calculated by year. Descriptive statistics, linear mixed modeling, and linear regression determined mean values, differences between residents, associations between independent variables and outcomes, and changes over time. Consistent differences between residents were assessed as a measure of good or bad luck / karma on call. RESULTS: During this time there were 23,032 patients and 30,766 anatomic regions scanned during 1,652 call shifts among 32 residents. Over the whole period, there were on average 10.6 patients and 14.3 body regions scanned on weekday shifts and 22.3 patients and 29.4 body regions scanned during weekend shifts. Annually, the mean number of patients, body regions, and RVUs scanned per shift increased by an average of 0.2 (1%), 0.4 (2%), and 1.2 (5%) (all p < 0.05) respectively in regression models. There was variability in call experiences, but only 1 resident had a disproportionate number of higher volume calls and fewer lower volume shifts than expected. CONCLUSIONS: Annual increases in scan volumes were modest. Although residents' experiences varied, little of this was attributable to consistent personal differences, including luck or call karma.


Assuntos
Plantão Médico/estatística & dados numéricos , Internato e Residência/estatística & dados numéricos , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos , Canadá , Humanos
14.
Carcinogenesis ; 42(5): 742-752, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-33623991

RESUMO

The incidence of malignant melanoma, a neoplasm of melanocytic cells, is increasing rapidly. The lymph nodes are often the first site of metastasis and can herald systemic dissemination, which is almost uniformly fatal. RLIP, a multi-specific ATP-dependent transporter that is over-expressed in several types of cancers, plays a central role in cancer cell resistance to radiation and chemotherapy. RLIP appears to be necessary for cancer cell survival because both in vitro cell culture and in vivo animal tumor studies show that the depletion or inhibition of RLIP causes selective toxicity to malignant cells. RLIP depletion/inhibition triggers apoptosis in cancer cells by inducing the accumulation of endogenously formed glutathione-conjugates. In our in vivo studies, we administered RLIP antibodies or antisense oligonucleotides to mice bearing subcutaneous xenografts of SKMEL2 and SKMEL5 melanoma cells and demonstrated that both treatments caused significant xenograft regression with no apparent toxic effects. Anti-RLIP antibodies and antisense, which respectively inhibit RLIP-mediated transport and deplete RLIP expression, showed similar tumor regressing activities, indicating that the inhibition of RLIP transport activity at the cell surface is sufficient to achieve anti-tumor activity. Furthermore, RLIP antisense treatment reduced levels of RLIP, pSTAT3, pJAK2, pSrc, Mcl-1 and Bcl2, as well as CDK4 and cyclin B1, and increased levels of Bax and phospho 5' AMP-activated protein kinase (pAMPK). These studies indicate that RLIP serves as a key effector in the survival of melanoma cells and is a valid target for cancer therapy. Overall, compounds that inhibit, deplete or downregulate RLIP will function as wide-spectrum agents to treat melanoma, independent of common signaling pathway mutations.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Proteínas Ativadoras de GTPase/genética , Janus Quinase 2/genética , Melanoma/genética , Fator de Transcrição STAT3/genética , Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Transportadores de Cassetes de Ligação de ATP/imunologia , Animais , Anticorpos Anti-Idiotípicos/farmacologia , Apoptose/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Proteínas Ativadoras de GTPase/antagonistas & inibidores , Proteínas Ativadoras de GTPase/imunologia , Humanos , Melanoma/patologia , Camundongos , Proteínas de Neoplasias/genética , Transdução de Sinais/genética , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Carcinogenesis ; 42(1): 48-57, 2021 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-32426802

RESUMO

Breast cancer (BC) remains one of the major causes of cancer deaths in women. Over half of all BCs carry genetic defects in the gene encoding p53, a powerful tumor suppressor. P53 is known as the 'guardian of the genome' because it is essential for regulating cell division and preventing tumor formation. Ral-interacting protein (RLIP) is a modular protein capable of participating in many cellular functions. Blocking this stress-responsive protein, which is overexpressed during malignancy, enables BC cells to overcome the deleterious effects of p53 loss more effectively. In the clustered regularly interspaced short palindromic repeats/CRISPR-associated protein (CRISPR/Cas9) system, a single-guide RNA (sgRNA) recognizes a specific DNA sequence and directs the endonuclease Cas9 to make a double-strand break, which enables editing of targeted genes. Here, we harnessed CRISPR/Cas9 technology to target the RLIP gene in BC cells. We screened sgRNAs using a reporter system and lentivirally delivered them, along with Cas9, to BC cells for validation. We then assessed the survival, proliferation, and tumorigenicity of BC cells in vitro and the growth of tumors in vivo after CRISPR-mediated knockdown of RLIP. Doxycycline-inducible expression of Cas9 in BC cells transduced with lentiviral vectors encoding the sgRNAs disrupted the RLIP gene, leading to inhibition of BC cell proliferation both in vitro and in vivo, with resected tumors showing reduced levels of the survival and proliferation markers Ki67, RLIP, pAkt, and survivin, the cell cycle protein CDK4, and the mesenchymal marker vimentin, as well as elevated levels of the differentiation protein E-cadherin and pro-apoptotic protein Bim. Inducible Cas9/sgRNA-transduced BC cells without doxycycline treatment did not exhibit altered cell survival or proliferation in vitro or in vivo. Our study provides proof-of-concept that the CRISPR/Cas9 system can be utilized to target RLIP in vitro and in vivo.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Neoplasias da Mama/terapia , Sistemas CRISPR-Cas/genética , Proteínas Ativadoras de GTPase/genética , Terapia Genética/métodos , Transportadores de Cassetes de Ligação de ATP/metabolismo , Apoptose/genética , Neoplasias da Mama/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Sobrevivência Celular/genética , Feminino , Proteínas Ativadoras de GTPase/metabolismo , Edição de Genes/métodos , Técnicas de Silenciamento de Genes , Humanos , Estudo de Prova de Conceito , RNA Guia de Cinetoplastídeos/genética , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Clin Infect Dis ; 73(7): e2278-e2284, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-32761083

RESUMO

BACKGROUND: Increased risk of progression from latent tuberculosis infection (LTBI) to tuberculosis (TB) disease among people living with human immunodeficiency virus (HIV; PLWH) prioritizes them for LTBI testing and treatment. Studies comparing the performance of interferon gamma release assays (IGRAs) and the tuberculin skin test (TST) among PLWH are lacking. METHODS: We used Bayesian latent class analysis to estimate the prevalence of LTBI and diagnostic characteristics of the TST, QuantiFERON Gold In-Tube (QFT), and T.SPOT-TB (TSPOT) among a prospective, multicenter cohort of US-born PLWH ≥5 years old with valid results for all 3 LTBI tests using standard US cutoffs (≥5 mm TST, ≥0.35 IU/mL QFT, ≥8 spots TSPOT). We also explored the performance of varying LTBI test cutoffs. RESULTS: Among 1510 PLWH (median CD4+ count 532 cells/mm3), estimated LTBI prevalence was 4.7%. TSPOT was significantly more specific (99.7%) and had a significantly higher positive predictive value (90.0%, PPV) than QFT (96.5% specificity, 50.7% PPV) and TST (96.8% specificity, 45.4% PPV). QFT was significantly more sensitive (72.2%) than TST (54.2%) and TSPOT (51.9%); negative predictive value of all tests was high (TST 97.7%, QFT 98.6%, TSPOT 97.6%). Even at the highest cutoffs evaluated (15 mm TST, ≥1.00 IU/mL QFT, ≥8 spots TSPOT), TST and QFT specificity was significantly lower than TSPOT. CONCLUSIONS: LTBI prevalence among this cohort of US-born PLWH was low compared to non-US born persons. TSPOT's higher PPV may make it preferable for testing US-born PLWH at low risk for TB exposure and with high CD4+ counts.


Assuntos
Infecções por HIV , Tuberculose Latente , Teorema de Bayes , Pré-Escolar , HIV , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Humanos , Testes de Liberação de Interferon-gama , Tuberculose Latente/diagnóstico , Tuberculose Latente/epidemiologia , Estudos Prospectivos , Teste Tuberculínico
17.
J Clin Microbiol ; 59(8): e0007421, 2021 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-33789959

RESUMO

Transrenal urine cell-free DNA (cfDNA) is a promising tuberculosis (TB) biomarker, but is challenging to detect because of the short length (<100 bp) and low concentration of TB-specific fragments. We aimed to improve the diagnostic sensitivity of TB urine cfDNA by increasing recovery of short fragments during sample preparation. We developed a highly sensitive sequence-specific purification method that uses hybridization probes immobilized on magnetic beads to capture short TB cfDNA (50 bp) with 91.8% average efficiency. Combined with short-target PCR, the assay limit of detection was ≤5 copies of cfDNA in 10 ml urine. In a clinical cohort study in South Africa, our urine cfDNA assay had 83.7% sensitivity (95% CI: 71.0 to 91.5%) and 100% specificity (95% CI: 86.2 to 100%) for diagnosis of active pulmonary TB when using sputum Xpert MTB/RIF as the reference standard. The detected cfDNA concentration was 0.14 to 2,804 copies/ml (median 14.6 copies/ml) and was inversely correlated with CD4 count and days to culture positivity. Sensitivity was nonsignificantly higher in HIV-positive (88.2%) compared to HIV-negative patients (73.3%), and was not dependent on CD4 count. Sensitivity remained high in sputum smear-negative (76.0%) and urine lipoarabinomannan (LAM)-negative (76.5%) patients. With improved sample preparation, urine cfDNA is a viable biomarker for TB diagnosis. Our assay has the highest reported accuracy of any TB urine cfDNA test to date and has the potential to enable rapid non-sputum-based TB diagnosis across key underserved patient populations.


Assuntos
Ácidos Nucleicos Livres , Tuberculose Pulmonar , Estudos de Coortes , Infecções por HIV , Humanos , Mycobacterium tuberculosis/genética , Sensibilidade e Especificidade , África do Sul , Escarro , Tuberculose Pulmonar/diagnóstico
18.
Mol Carcinog ; 60(3): 213-223, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33544936

RESUMO

The overexpression and amplification of the protooncogene neu (ERBB2) play an important role in the development of aggressive breast cancer (BC) in humans. Ral-interacting protein (RLIP), a modular stress-response protein with pleiotropic functions, is overexpressed in several types of cancer, including BC. Here, we show that blocking RLIP attenuates the deleterious effects caused by the loss of the tumor suppressor p53 and inhibits the growth of human BC both in vitro and in vivo in MMTV-neu mice. In addition, we show that treatment with the diet-derived, RLIP-targeting chemotherapeutic 2'-hydroxyflavanone (2HF), alone or in combination with RLIP-specific antisense RNA or antibodies, significantly reduced the cumulative incidence and/or burden of mammary hyperplasia and carcinoma in MMTV-neu mice. 2HF treatment correlated with reduced tumor cell proliferation and increased apoptosis, and the average number of Ki67-positive (proliferating) cells was significantly lower in the tumors of 2HF-treated mice than in the tumors of control mice. Furthermore, targeting RLIP also resulted in the overexpression of E-cadherin and the infiltration of CD3+ T cells into mammary tumors. Taken together, these results underscore the translational potential of RLIP-targeting agents and provide a strong rationale to validate them in the clinic.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Anticarcinógenos/farmacologia , Neoplasias da Mama/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Neoplasias Mamárias Experimentais/prevenção & controle , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Flavanonas/farmacologia , Proteínas Ativadoras de GTPase/genética , Humanos , Linfócitos do Interstício Tumoral/efeitos dos fármacos , Glândulas Mamárias Animais/efeitos dos fármacos , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/patologia , Camundongos Transgênicos , Terapia de Alvo Molecular , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Receptor ErbB-2/metabolismo
19.
J Cardiovasc Magn Reson ; 23(1): 44, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33794918

RESUMO

The Society for Cardiovascular Magnetic Resonance (SCMR) is an international society focused on the research, education, and clinical application of cardiovascular magnetic resonance (CMR). The SCMR web site ( https://www.scmr.org ) hosts a case series designed to present case reports demonstrating the unique attributes of CMR in the diagnosis or management of cardiovascular disease. Each clinical presentation is followed by a brief discussion of the disease and unique role of CMR in disease diagnosis or management guidance. By nature, some of these are somewhat esoteric, but all are instructive. In this publication, we provide a digital archive of the 2019 Case of the Week series as a means of further enhancing the education of those interested in CMR and as a means of more readily identifying these cases using a PubMed or similar search engine.


Assuntos
Síndrome de Churg-Strauss/diagnóstico por imagem , Imageamento por Ressonância Magnética , Trombose/diagnóstico por imagem , Disfunção Ventricular Esquerda/diagnóstico por imagem , Antineoplásicos/efeitos adversos , Cardiotoxicidade , Síndrome de Churg-Strauss/fisiopatologia , Síndrome de Churg-Strauss/terapia , Diagnóstico Diferencial , Feminino , Neoplasias Cardíacas/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Trombose/fisiopatologia , Trombose/terapia , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/terapia , Função Ventricular Esquerda/efeitos dos fármacos , Adulto Jovem
20.
BMC Infect Dis ; 21(1): 218, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33632173

RESUMO

BACKGROUND: People living with HIV (PLHIV) who reside in high tuberculosis burden settings remain at risk for tuberculosis disease despite treatment with anti-retroviral therapy and isoniazid preventive therapy (IPT). The performance of the World Health Organization (WHO) symptom screen for tuberculosis in PLHIV receiving anti-retroviral therapy is sub-optimal and alternative screening strategies are needed. METHODS: We enrolled HIV-positive adults into a prospective study in western Kenya. Individuals who were IPT-naïve or had completed IPT > 6 months prior to enrollment were eligible. We evaluated tuberculosis prevalence overall and by IPT status. We assessed the accuracy of the WHO symptom screen, GeneXpert MTB/RIF (Xpert), and candidate biomarkers including C-reactive protein (CRP), hemoglobin, erythrocyte sedimentation rate (ESR), and monocyte-to-lymphocyte ratio for identifying pulmonary tuberculosis. Some participants were evaluated at 6 months post-enrollment for tuberculosis. RESULTS: The study included 383 PLHIV, of whom > 99% were on antiretrovirals and 88% had received IPT, completed a median of 1.1 years (IQR 0.8-1.55) prior to enrollment. The prevalence of pulmonary tuberculosis at enrollment was 1.3% (n = 5, 95% CI 0.4-3.0%): 4.3% (0.5-14.5%) among IPT-naïve and 0.9% (0.2-2.6%) among IPT-treated participants. The sensitivity of the WHO symptom screen was 0% (0-52%) and specificity 87% (83-90%). Xpert and candidate biomarkers had poor to moderate sensitivity; the most accurate biomarker was CRP ≥ 3.3 mg/L (sensitivity 80% (28-100) and specificity 72% (67-77)). Six months after enrollment, the incidence rate of pulmonary tuberculosis following IPT completion was 0.84 per 100 person-years (95% CI, 0.31-2.23). CONCLUSIONS: In Kenyan PLHIV treated with IPT, tuberculosis prevalence was low at a median of 1.4 years after IPT completion. WHO symptoms screening, Xpert, and candidate biomarkers were insensitive for identifying pulmonary tuberculosis in antiretroviral-treated PLHIV.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Antirretrovirais/uso terapêutico , Programas de Rastreamento/estatística & dados numéricos , Tuberculose Pulmonar/epidemiologia , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/prevenção & controle , Adulto , Antituberculosos/uso terapêutico , Feminino , Humanos , Isoniazida/uso terapêutico , Quênia/epidemiologia , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/prevenção & controle
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