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1.
Nature ; 623(7989): 1079-1085, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37938782

RESUMO

Decades of previous efforts to develop renal-sparing polyene antifungals were misguided by the classic membrane permeabilization model1. Recently, the clinically vital but also highly renal-toxic small-molecule natural product amphotericin B was instead found to kill fungi primarily by forming extramembraneous sponge-like aggregates that extract ergosterol from lipid bilayers2-6. Here we show that rapid and selective extraction of fungal ergosterol can yield potent and renal-sparing polyene antifungals. Cholesterol extraction was found to drive the toxicity of amphotericin B to human renal cells. Our examination of high-resolution structures of amphotericin B sponges in sterol-free and sterol-bound states guided us to a promising structural derivative that does not bind cholesterol and is thus renal sparing. This derivative was also less potent because it extracts ergosterol more slowly. Selective acceleration of ergosterol extraction with a second structural modification yielded a new polyene, AM-2-19, that is renal sparing in mice and primary human renal cells, potent against hundreds of pathogenic fungal strains, resistance evasive following serial passage in vitro and highly efficacious in animal models of invasive fungal infections. Thus, rational tuning of the dynamics of interactions between small molecules may lead to better treatments for fungal infections that still kill millions of people annually7,8 and potentially other resistance-evasive antimicrobials, including those that have recently been shown to operate through supramolecular structures that target specific lipids9.


Assuntos
Antifúngicos , Rim , Polienos , Esteróis , Animais , Humanos , Camundongos , Anfotericina B/análogos & derivados , Anfotericina B/química , Anfotericina B/toxicidade , Antifúngicos/química , Antifúngicos/metabolismo , Antifúngicos/farmacologia , Antifúngicos/toxicidade , Células Cultivadas , Colesterol/química , Colesterol/metabolismo , Farmacorresistência Fúngica , Ergosterol/química , Ergosterol/metabolismo , Rim/efeitos dos fármacos , Cinética , Testes de Sensibilidade Microbiana , Micoses/tratamento farmacológico , Micoses/microbiologia , Polienos/química , Polienos/metabolismo , Polienos/farmacologia , Inoculações Seriadas , Esteróis/química , Esteróis/metabolismo , Fatores de Tempo
2.
Nat Chem Biol ; 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38664586

RESUMO

The natural product hinokitiol mobilizes iron across lipid bilayers at low concentrations and restores hemoglobinization in iron transporter protein-deficient systems. But hinokitiol fails to similarly mobilize iron at higher concentrations, limiting its uses in chemical biology and medicine. Here we show that at higher concentrations, hinokitiol3:Fe(III) complexes form large, higher-order aggregates, leading to loss of transmembrane iron mobilization. Guided by this understanding and systematic structure-function studies enabled by modular synthesis, we identified FeM-1269, which minimally aggregates and dose-dependently mobilizes iron across lipid bilayers even at very high concentrations. In contrast to hinokitiol, FeM-1269 is also well-tolerated in animals at high doses for extended periods of time. In a mouse model of anemia of inflammation, FeM-1269 increases serum iron, transferrin saturation, hemoglobin and hematocrit. This rationally developed iron-mobilizing small molecule has enhanced potential as a molecular prosthetic for understanding and potentially treating iron transporter deficiencies.

3.
BJU Int ; 132(2): 188-195, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36855895

RESUMO

OBJECTIVES: To assess of the clinical performance of Proclarix® (a novel Conformité Européenne [CE]-marked biomarker test aiding in the identification of clinically significant prostate cancer [csPCa]) alone or in combination with multiparametric magnetic resonance imaging (mpMRI) to predict csPCa (International Society of Urological Pathology Grade Group ≥2). PATIENTS AND METHODS: The study included blood samples from 721 men undergoing mpMRI followed by biopsy at University College London, London, and Vall d'Hebron University Hospital, Barcelona. Samples were tested blindly. The Proclarix-MRI model combining prostate volume, Proclarix and mpMRI results was trained using the UCL cohort (n = 159) and validated in the Vall d'Hebron cohort (n = 562). Its diagnostic performance was established in correlation to biopsy outcome and compared to available clinical parameters and risk calculators. RESULTS: Clinical performance of the Proclarix-MRI model in the validation cohort did not significantly differ from the training cohort and resulted in a sensitivity for csPCa of 90%, 90% negative predictive value and 66% positive predictive value. The Proclarix-MRI score's specificity (68%) was significantly (P < 0.001) better than the MRI-European Randomized study of Screening for Prostate Cancer risk score (51%), Proclarix (27%) or mpMRI (28%) alone. In addition, Proclarix by itself was found to be useful in the MRI Prostate Imaging-Reporting and Data System (PI-RADS) score 3 subgroup by outperforming prostate-specific antigen density in terms of specificity (25% vs 13%, P = 0.004) at 100% sensitivity. CONCLUSION: When combined with mpMRI and prostate volume, Proclarix reliably predicted csPCa and ruled out men with no or indolent cancer. A large reduction of two thirds of unneeded biopsies was achieved. Proclarix can further be used with high confidence to reliably detect csPCa in men with an indeterminate PI-RADS score 3 mpMRI. Despite these encouraging results, further validation is needed.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Biópsia , Valor Preditivo dos Testes , Biópsia Guiada por Imagem/métodos
4.
J Transl Med ; 20(1): 611, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36544142

RESUMO

BACKGROUND: High-grade serous carcinoma (HGSC) is the most common and deadly subtype of ovarian cancer. Although most patients will initially respond to first-line treatment with a combination of surgery and platinum-based chemotherapy, up to a quarter will be resistant to treatment. We aimed to identify a new strategy to improve HGSC patient management at the time of cancer diagnosis (HGSC-1LTR). METHODS: A total of 109 ready-available formalin-fixed paraffin-embedded HGSC tissues obtained at the time of HGSC diagnosis were selected for proteomic analysis. Clinical data, treatment approach and outcomes were collected for all patients. An initial discovery cohort (n = 21) were divided into chemoresistant and chemosensitive groups and evaluated using discovery mass-spectrometry (MS)-based proteomics. Proteins showing differential abundance between groups were verified in a verification cohort (n = 88) using targeted MS-based proteomics. A logistic regression model was used to select those proteins able to correctly classify patients into chemoresistant and chemosensitive. The classification performance of the protein and clinical data combinations were assessed through the generation of receiver operating characteristic (ROC) curves. RESULTS: Using the HGSC-1LTR strategy we have identified a molecular signature (TKT, LAMC1 and FUCO) that combined with ready available clinical data (patients' age, menopausal status, serum CA125 levels, and treatment approach) is able to predict patient response to first-line treatment with an AUC: 0.82 (95% CI 0.72-0.92). CONCLUSIONS: We have established a new strategy that combines molecular and clinical parameters to predict the response to first-line treatment in HGSC patients (HGSC-1LTR). This strategy can allow the identification of chemoresistance at the time of diagnosis providing the optimization of therapeutic decision making and the evaluation of alternative treatment strategies. Thus, advancing towards the improvement of patient outcome and the individualization of HGSC patients' care.


Assuntos
Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Humanos , Feminino , Proteômica/métodos , Cistadenocarcinoma Seroso/diagnóstico , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/genética , Neoplasias Ovarianas/tratamento farmacológico , Proteínas/uso terapêutico , Biomarcadores Tumorais/metabolismo
5.
BJU Int ; 129(5): 627-633, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34375498

RESUMO

OBJECTIVE: To analyse the current predictive value of isolated high-grade prostatic intraepithelial neoplasia (HGPIN) for clinically significant prostate cancer (csPCa) detection in repeat biopsies. PATIENTS AND METHODS: A cohort of 293 men with isolated HGPIN detected in previous biopsies performed without multiparametric magnetic resonance imaging (mpMRI), and who underwent repeat biopsy within 1 to 3 years, was analysed. Pre-repeat biopsy mpMRI and guided biopsies to suspicious lesions (Prostate Imaging - Reporting and Data System [PI-RADS] ≥3) and/or and systematic biopsies were performed. Persistent prostate cancer (PCa) suspicion, defined as sustained serum prostate-specific antigen level >4 ng/mL and/or abnormal digital rectal examination, was present in 248 men (84.6%), and was absent in 45 men (15.4%). A control group of 190 men who had no previous HGPIN, atypical small acinar proliferation or HGPIN with atypia who were scheduled to undergo repeat biopsy due to persistent PCa suspicion were also analysed. csPCa was defined as tumours of Grade Group ≥2. RESULTS: In the subset of 45 men with isolated HGPIN, in whom PCa suspicion disappeared, only one csPCa (2.2%) and one insignificant PCa (iPCa) were detected. csPCa was detected in 34.7% of men with persistent PCa suspicion and previous HGPIN, and in 28.4% of those without previous HGPIN (P =0.180). iPCa was detected in 12.1% and 6.3%, respectively (P =0.039). Logistic regression analysis showed that the risk of csPCa detection was not predicted by previous HGPIN: odds ratio (OR) 1.369 (95% confidence interval [CI] 0.894-2.095; P =0.149); however, previous HGPIN increased the risk of iPCa detection: OR 2.043 (95% CI 1.016-4.109; P =0.006). CONCLUSION: The risk of csPCa in men with isolated HGPIN, in whom PCa suspicion disappears, is extremely low. Moreover, in those men in whom PCa suspicion persists, the risk of csPCa is not influenced by the previous finding of HGPIN. However, previous HGPIN increases the risk of iPCa detection. Therefore, repeat prostate biopsy should not be recommended solely because of a previous HGPIN.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasia Prostática Intraepitelial , Neoplasias da Próstata , Neoplasias Urológicas , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Próstata/patologia , Neoplasia Prostática Intraepitelial/patologia , Neoplasias da Próstata/patologia , Neoplasias Urológicas/patologia
6.
Mol Cell ; 46(3): 274-86, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-22483620

RESUMO

The Ska complex is an essential mitotic component required for accurate cell division in human cells. It is composed of three subunits that function together to establish stable kinetochore-microtubule interactions in concert with the Ndc80 network. We show that the structure of the Ska core complex is a W-shaped dimer of coiled coils, formed by intertwined interactions between Ska1, Ska2, and Ska3. The C-terminal domains of Ska1 and Ska3 protrude at each end of the homodimer, bind microtubules in vitro when connected to the central core, and are essential in vivo. Mutations disrupting the central coiled coil or the dimerization interface result in chromosome congression failure followed by cell death. The Ska complex is thus endowed with bipartite and cooperative tubulin-binding properties at the ends of a 350 Å-long molecule. We discuss how this symmetric architecture might complement and stabilize the Ndc80-microtubule attachments with analogies to the yeast Dam1/DASH complex.


Assuntos
Proteínas Cromossômicas não Histona/fisiologia , Cinetocoros/metabolismo , Proteínas Associadas aos Microtúbulos/fisiologia , Microtúbulos/metabolismo , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Ciclo Celular , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/metabolismo , Humanos , Cinetocoros/química , Proteínas Associadas aos Microtúbulos/química , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/química , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Alinhamento de Sequência
7.
Cell Mol Life Sci ; 76(11): 2231-2243, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30770954

RESUMO

Current therapies for most non-infectious diseases are directed at or affect functionality of the human translated genome, barely 2% of all genetic information. By contrast, the therapeutic potential of targeting the transcriptome, ~ 70% of the genome, remains largely unexplored. RNA therapeutics is an emerging field that widens the range of druggable targets and includes elements such as microRNA. Here, we sought to screen for microRNA with tumor-suppressive functions in neuroblastoma, an aggressive pediatric tumor of the sympathetic nervous system that requires the development of new therapies. We found miR-323a-5p and miR-342-5p to be capable of reducing cell proliferation in multiple neuroblastoma cell lines in vitro and in vivo, thereby providing a proof of concept for miRNA-based therapies for neuroblastoma. Furthermore, the combined inhibition of the direct identified targets such as CCND1, CHAF1A, INCENP and BCL-XL could reveal new vulnerabilities of high-risk neuroblastoma.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias do Sistema Nervoso/genética , Neuroblastoma/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Criança , Fator 1 de Modelagem da Cromatina/genética , Fator 1 de Modelagem da Cromatina/metabolismo , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Ciclina D1/genética , Ciclina D1/metabolismo , Feminino , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Camundongos , Camundongos Nus , MicroRNAs/metabolismo , Neoplasias do Sistema Nervoso/mortalidade , Neoplasias do Sistema Nervoso/patologia , Neoplasias do Sistema Nervoso/terapia , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Neuroblastoma/terapia , Neurônios/metabolismo , Neurônios/patologia , Ligação Proteica , Transdução de Sinais , Análise de Sobrevida , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Proteína bcl-X/genética , Proteína bcl-X/metabolismo
8.
J Pathol ; 241(4): 475-487, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27873306

RESUMO

Endometrial cancer is the most common gynaecological cancer in western countries, being the most common subtype of endometrioid tumours. Most patients are diagnosed at an early stage and present an excellent prognosis. However, a number of those continue to suffer recurrence, without means of identification by risk classification systems. Thus, finding a reliable marker to predict recurrence becomes an important unmet clinical issue. ALCAM is a cell-cell adhesion molecule and member of the immunoglobulin superfamily that has been associated with the genesis of many cancers. Here, we first determined the value of ALCAM as a marker of recurrence in endometrioid endometrial cancer by conducting a retrospective multicentre study of 174 primary tumours. In early-stage patients (N = 134), recurrence-free survival was poorer in patients with ALCAM-positive compared to ALCAM-negative tumours (HR 4.237; 95% CI 1.01-17.76). This difference was more significant in patients with early-stage moderately-poorly differentiated tumours (HR 9.259; 95% CI 2.12-53.47). In multivariate analysis, ALCAM positivity was an independent prognostic factor in early-stage disease (HR 6.027; 95% CI 1.41-25.74). Then we demonstrated in vitro a role for ALCAM in cell migration and invasion by using a loss-of-function model in two endometrial cancer cell lines. ALCAM depletion resulted in a reduced primary tumour size and reduced metastatic local spread in an orthotopic murine model. Gene expression analysis of ALCAM-depleted cell lines pointed to motility, invasiveness, cellular assembly, and organization as the most deregulated functions. Finally, we assessed some of the downstream effector genes that are involved in ALCAM-mediated cell migration; specifically FLNB, TXNRD1, and LAMC2 were validated at the mRNA and protein level. In conclusion, our results highlight the potential of ALCAM as a recurrent biomarker in early-stage endometrioid endometrial cancer and point to ALCAM as an important molecule in endometrial cancer dissemination by regulating cell migration, invasion, and metastasis. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Antígenos CD/genética , Biomarcadores Tumorais/genética , Carcinoma Endometrioide/genética , Moléculas de Adesão Celular Neuronais/genética , Neoplasias do Endométrio/genética , Proteínas Fetais/genética , Regulação Neoplásica da Expressão Gênica , Idoso , Animais , Antígenos CD/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Endometrioide/diagnóstico , Carcinoma Endometrioide/patologia , Moléculas de Adesão Celular Neuronais/metabolismo , Movimento Celular , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/patologia , Feminino , Proteínas Fetais/metabolismo , Filaminas/genética , Filaminas/metabolismo , Humanos , Laminina/genética , Laminina/metabolismo , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Invasividade Neoplásica , Metástase Neoplásica , Prognóstico , Estudos Retrospectivos , Transdução de Sinais , Tiorredoxina Redutase 1/genética , Tiorredoxina Redutase 1/metabolismo
9.
Phytother Res ; 31(1): 124-131, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27739110

RESUMO

Several human skin diseases are associated with fungi as dermatophytes and Malassezia. Skin mycoses are increasing and new alternatives to conventional treatments with improved efficacy and/or safety profiles are desirable. For the first time, the anti-dermatophytes and the anti-Malassezia activities of Vitis vinifera seed extracts obtained from different table and wine cultivars have been evaluated. Geometric minimal inhibitory concentration ranged from 20 to 97 µg/mL for dermatophytes and from 32 to 161 µg/mL for Malassezia furfur. Dried grape seed extracts analyzed by HPLC/DAD/ESI/MS showed different quali-quantitative compositions in terms of monomeric and polymeric flavan-3-ols. The minimal inhibitory concentrations for Trichophyton mentagrophytes and for M. furfur were inversely correlated with the amount of the polymeric fraction (r = -0.7639 and r = -0.7228, respectively). Differently, the antifungal activity against T. mentagrophytes was not correlated to the content of flavan-3-ol monomers (r = 0.2920) and only weakly correlated for M. furfur (r = -0.53604). These results suggest that extracts rich in polymeric flavan-3-ols, recovered from V. vinifera seeds, could be used for the treatment of skin fungal infections. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Antifúngicos/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Flavonoides/química , Malassezia/efeitos dos fármacos , Extratos Vegetais/química , Sementes/química , Vitis/química , Extratos Vegetais/farmacologia
10.
J Transl Med ; 14(1): 180, 2016 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-27317346

RESUMO

BACKGROUND: Uterine aspirates are used in the diagnostic process of endometrial disorders, yet further applications could emerge if its complex milieu was simplified. Exosome-like vesicles isolated from uterine aspirates could become an attractive source of biomarkers, but there is a need to standardize isolation protocols. The objective of the study was to determine whether exosome-like vesicles exist in the fluid fraction of uterine aspirates and to compare protocols for their isolation, characterization, and analysis. METHODS: We collected uterine aspirates from 39 pre-menopausal women suffering from benign gynecological diseases. The fluid fraction of 27 of those aspirates were pooled and split into equal volumes to evaluate three differential centrifugation-based procedures: (1) a standard protocol, (2) a filtration protocol, and (3) a sucrose cushion protocol. Characterization of isolated vesicles was assessed by electron microscopy, nanoparticle tracking analysis and immunoblot. Specifically for RNA material, we evaluate the effect of sonication and RNase A treatment at different steps of the protocol. We finally confirmed the efficiency of the selected methods in non-pooled samples. RESULTS: All protocols were useful to isolate exosome-like vesicles. However, the Standard procedure was the best performing protocol to isolate exosome-like vesicles from uterine aspirates: nanoparticle tracking analysis revealed a higher concentration of vesicles with a mode of 135 ± 5 nm, and immunoblot showed a higher expression of exosome-related markers (CD9, CD63, and CD81) thus verifying an enrichment in this type of vesicles. RNA contained in exosome-like vesicles was successfully extracted with no sonication treatment and exogenous nucleic acids digestion with RNaseA, allowing the analysis of the specific inner cargo by Real-Time qPCR. CONCLUSION: We confirmed the existence of exosome-like vesicles in the fluid fraction of uterine aspirates. They were successfully isolated by differential centrifugation giving sufficient proteomic and transcriptomic material for further analyses. The Standard protocol was the best performing procedure since the other two tested protocols did not ameliorate neither yield nor purity of exosome-like vesicles. This study contributes to establishing the basis for future comparative studies to foster the field of biomarker research in gynecology.


Assuntos
Exossomos/metabolismo , Sucção/métodos , Ultracentrifugação/métodos , Útero/metabolismo , Feminino , Humanos , RNA/genética , RNA/metabolismo
11.
EMBO J ; 30(16): 3322-36, 2011 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-21772247

RESUMO

The spindle assembly checkpoint (SAC) restrains anaphase until all chromosomes become bi-oriented on the mitotic spindle. The SAC protein Mad2 can fold into two distinct conformers, open (O) and closed (C), and can asymmetrically dimerize. Here, we describe a monoclonal antibody that specifically recognizes the dimerization interface of C-Mad2. This antibody revealed several conformation-specific features of Mad2 in human cells. Notably, we show that Mad2 requires association with Mad1 to adopt the closed conformation and that the activity of the Mad1:C-Mad2 complex undergoes regulation by p31comet-dependent 'capping'. Furthermore, C-Mad2 antibody microinjection caused an abrupt termination of the SAC and accelerated mitotic progression. Remarkably, microinjection of a Mad1-neutralizing antibody triggered a comparable mitotic acceleration. Our study provides direct in vivo evidence for the model that a kinetochore complex of Mad1:C-Mad2 acts as a template to sustain the SAC and it challenges the distinction between SAC and mitotic timer.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Anáfase/fisiologia , Proteínas de Ligação ao Cálcio/fisiologia , Proteínas de Ciclo Celular/fisiologia , Proteínas Nucleares/fisiologia , Proteínas Repressoras/fisiologia , Fuso Acromático/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Animais , Anticorpos Monoclonais/imunologia , Proteínas de Ligação ao Cálcio/química , Proteínas de Ligação ao Cálcio/imunologia , Proteínas Cdc20 , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/imunologia , Dimerização , Humanos , Cinetocoros/metabolismo , Substâncias Macromoleculares , Proteínas Mad2 , Camundongos , Camundongos Endogâmicos BALB C , Mitose/efeitos dos fármacos , Mitose/fisiologia , Poro Nuclear/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/imunologia , Conformação Proteica , Dobramento de Proteína , Mapeamento de Interação de Proteínas , RNA Interferente Pequeno/farmacologia , Coelhos , Proteínas Repressoras/química , Proteínas Repressoras/imunologia , Fatores de Tempo
12.
J Proteome Res ; 13(12): 5973-88, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25330945

RESUMO

In recent years, directed and, particularly, targeted mass spectrometric workflows have gained momentum as alternative techniques to conventional data-dependent acquisition (DDA) LC-MS/MS approaches. By focusing on specific peptide species, these methods allow hypothesis-driven analysis of selected proteins of interest, and they have been shown to be suited to monitor low-abundance proteins within complex mixtures. Despite their growing popularity, no study has systematically evaluated these various MS strategies in terms of quantification, detection, and identification limits when they are applied to complex samples. Here, we systematically compared the performance of conventional DDA, directed, and various targeted MS approaches on two different instruments, namely, a hybrid linear ion trap--Orbitrap and a triple quadrupole instrument. We assessed the limits of identification, quantification, and detection for each method by analyzing a dilution series of 20 unmodified and 10 phosphorylated synthetic heavy-labeled reference peptides, respectively, covering 6 orders of magnitude in peptide concentration with and without a complex human cell digest background. We found that all methods performed similarly in the absence of background proteins; however, when analyzing whole-cell lysates, targeted methods were at least 5-10 times more sensitive than that of the directed or DDA method. In particular, higher stage fragmentation (MS3) of the neutral loss peak using a linear ion trap increased the dynamic quantification range of some phosphopeptides up to 100-fold. We illustrate the power of this targeted MS3 approach for phosphopeptide monitoring by successfully quantifying nine phosphorylation sites of the kinetochore and spindle assembly checkpoint component Mad1 over different cell cycle states from nonenriched pull-down samples.


Assuntos
Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Fosfopeptídeos/análise , Espectrometria de Massas em Tandem/métodos , Sequência de Aminoácidos , Sítios de Ligação , Proteínas de Ciclo Celular/metabolismo , Extratos Celulares/análise , Células HeLa , Humanos , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Fosfopeptídeos/metabolismo , Fosforilação , Proteômica/métodos , Reprodutibilidade dos Testes
13.
EMBO J ; 28(10): 1442-52, 2009 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-19360002

RESUMO

Ska1 and Ska2 form a complex at the kinetochore-microtubule (KT-MT) interface and are required for timely progression from metaphase to anaphase. Here, we use mass spectrometry to search for additional components of the Ska complex. We identify C13Orf3 (now termed Ska3) as a novel member of this complex and map the interaction domains among the three known components. Ska3 displays similar characteristics as Ska1 and Ska2: it localizes to the spindle and KT throughout mitosis and its depletion markedly delays anaphase transition. Interestingly, a more complete removal of the Ska complex by concomitant depletion of Ska1 and Ska3 results in a chromosome congression failure followed by cell death. This severe phenotype reflects a destabilization of KT-MT interactions, as demonstrated by reduced cold stability of KT fibres. Yet, the depletion of the Ska complex only marginally impairs KT localization of the KMN network responsible for MT attachment. We propose that the Ska complex functionally complements the KMN, providing an additional layer of stability to KT-MT attachment and possibly signalling completion of attachment to the spindle checkpoint.


Assuntos
Fenômenos Fisiológicos Celulares , Cinetocoros/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Mapeamento de Interação de Proteínas , Proteínas de Ciclo Celular , Proteínas Cromossômicas não Histona/metabolismo , Segregação de Cromossomos , Citocinese , Células HeLa , Humanos , Ligação Proteica
14.
Mol Cell Proteomics ; 10(1): M110.004457, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20860994

RESUMO

Polo-like kinases regulate many aspects of mitotic and meiotic progression from yeast to man. In early mitosis, mammalian Polo-like kinase 1 (Plk1) controls centrosome maturation, spindle assembly, and microtubule attachment to kinetochores. However, despite the essential and diverse functions of Plk1, the full range of Plk1 substrates remains to be explored. To investigate the Plk1-dependent phosphoproteome of the human mitotic spindle, we combined stable isotope labeling by amino acids in cell culture with Plk1 inactivation or depletion followed by spindle isolation and mass spectrometry. Our study identified 358 unique Plk1-dependent phosphorylation sites on spindle proteins, including novel substrates, illustrating the complexity of the Plk1-dependent signaling network. Over 100 sites were validated by in vitro phosphorylation of peptide arrays, resulting in a broadening of the Plk1 consensus motif. Collectively, our data provide a rich source of information on Plk1-dependent phosphorylation, Plk1 docking to substrates, the influence of phosphorylation on protein localization, and the functional interaction between Plk1 and Aurora A on the early mitotic spindle.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteoma/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Fuso Acromático/enzimologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Aurora Quinases , Centrossomo/enzimologia , Sequência Consenso , Ativação Enzimática , Células HeLa , Humanos , Cinesinas/metabolismo , Dados de Sequência Molecular , Fosfoproteínas/química , Fosforilação , Proteínas Serina-Treonina Quinases/química , Proteoma/química , RNA Interferente Pequeno/metabolismo , Reprodutibilidade dos Testes , Especificidade por Substrato , Quinase 1 Polo-Like
15.
Eur Urol Oncol ; 5(4): 460-463, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33653674

RESUMO

Posterior rhabdosphincter reconstruction (PRR) has been proposed to improve early urinary continence (UC) recovery after radical prostatectomy (RP). In order to generate level 1b evidence, we designed a double-blind randomised controlled trial powered to detect a 20% increase in early UC recovery after robot-assisted RP (RARP). A group of 153 patients with cT1c-3a N0M0 prostate cancer were randomised (73 to control arm and 80 to PRR arm) and 152 completed 12-mo follow-up. For UC defined as no pad use, the recovery hazard ratio at 1-mo follow-up was 2.312 (95% confidence interval [CI] 1.081-4.937; p = 0.030). UC recovery was observed in 33.8% of patients in the PRR arm and 18.1% of patients in the control arm (p = 0.022). At 3-mo follow-up the corresponding rates were 58.8% and 43.1% (p = 0.038). The median time to UC recovery was 106 d (95% CI 73-139) in the control arm and 64 d (95% CI 39-89) in PRR arm (p = 0.897). No differences in pathological outcomes or early and late surgical complications were observed between the arms. We conclude that PRR is safe and increases early UC recovery after RARP. PATIENT SUMMARY: We investigated reconstruction of a muscular ring that controls the flow of urine, called the rhabdosphincter, after removal of the prostate in robot-assisted surgery. The procedure is safe and increases early recovery of urinary continence. This trial is registered at ClinicalTrials.gov as NCT03302169.


Assuntos
Robótica , Incontinência Urinária , Humanos , Masculino , Próstata/cirurgia , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Recuperação de Função Fisiológica , Resultado do Tratamento , Incontinência Urinária/etiologia , Incontinência Urinária/prevenção & controle
16.
Sci Rep ; 12(1): 4445, 2022 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-35292711

RESUMO

Despite recent advances in the management of BRCA1 mutated high-grade serous ovarian cancer (HGSC), the physiology of these tumors remains poorly understood. Here we provide a comprehensive molecular understanding of the signaling processes that drive HGSC pathogenesis with the addition of valuable ubiquitination profiling, and their dependency on BRCA1 mutation-state directly in patient-derived tissues. Using a multilayered proteomic approach, we show the tight coordination between the ubiquitination and phosphorylation regulatory layers and their role in key cellular processes related to BRCA1-dependent HGSC pathogenesis. In addition, we identify key bridging proteins, kinase activity, and post-translational modifications responsible for molding distinct cancer phenotypes, thus providing new opportunities for therapeutic intervention, and ultimately advance towards a more personalized patient care.


Assuntos
Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Cistadenocarcinoma Seroso/genética , Cistadenocarcinoma Seroso/patologia , Reparo do DNA , Feminino , Humanos , Mutação , Neoplasias Ovarianas/patologia , Proteômica
17.
Cancers (Basel) ; 14(10)2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35625978

RESUMO

This study is a head-to-head comparison between mPSAD and MRI-PMbdex. The MRI-PMbdex was created from 2432 men with suspected PCa; this cohort comprised the development and external validation cohorts of the Barcelona MRI predictive model. Pre-biopsy 3-Tesla multiparametric MRI (mpMRI) and 2 to 4-core transrectal ultrasound (TRUS)-guided biopsies for suspicious lesions and/or 12-core TRUS systematic biopsies were scheduled. Clinically significant PCa (csPCa), defined as Gleason-based Grade Group 2 or higher, was detected in 934 men (38.4%). The area under the curve was 0.893 (95% confidence interval [CI]: 0.880−0.906) for MRI-PMbdex and 0.764 (95% CI: 0.774−0.783) for mPSAD, with p < 0.001. MRI-PMbdex showed net benefit over biopsy in all men when the probability of csPCa was greater than 2%, while mPSAD did the same when the probability of csPCa was greater than 18%. Thresholds of 13.5% for MRI-PMbdex and 0.628 ng/mL2 for mPSAD had 95% sensitivity for csPCa and presented 51.1% specificity for MRI-PMbdex and 19.6% specificity for mPSAD, with p < 0.001. MRI-PMbdex exhibited net benefit over mPSAD in men with prostate imaging report and data system (PI-RADS) <4, while neither exhibited any benefit in men with PI-RADS 5. Hence, we can conclude that MRI-PMbdex is more accurate than mPSAD for the proper selection of candidates for prostate biopsy among men with suspected PCa, with the exception of men with a PI-RAD S 5 score, for whom neither tool exhibited clinical guidance to determine the need for biopsy.

18.
Cancers (Basel) ; 14(11)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35681685

RESUMO

Tools to properly select candidates for prostate biopsy after magnetic resonance imaging (MRI) have usually been analyzed in overall populations with suspected prostate cancer (PCa). However, the performance of these tools can change regarding the Prostate Imaging-Reporting and Data System (PI-RADS) categories due to the different incidence of clinically significant PCa (csPCa). The objective of the study was to analyze PSA density (PSAD), MRI-ERSPC risk calculator (RC), and Proclarix to properly select candidates for prostate biopsy regarding PI-RADS categories. We performed a head-to-head analysis of 567 men with suspected PCa, PSA > 3 ng/mL and/or abnormal rectal examination, in whom two to four core transrectal ultrasound (TRUS) guided biopsies to PI-RADS ≥ three lesions and/or 12-core TRUS systematic biopsies were performed after 3-tesla mpMRI between January 2018 and March 2020 in one academic institution. The overall detection of csPCa was 40.9% (6% in PI-RADS < 3, 14.8% in PI-RADS 3, 55.3% in PI-RADS 4, and 88.9% in PI-RADS 5). MRI-ERSPC model exhibited a net benefit over PSAD and Proclarix in the overall population. Proclarix outperformed PSAD and MRI-ERSPC RC in PI-RADS ≤ 3. PSAD outperformed MRI-ESRPC RC and Proclarix in PI-RADS > 3, although none of them exhibited 100% sensitivity for csPCa in this setting. Therefore, tools to properly select candidates for prostate biopsy after MRI must be analyzed regarding the PI-RADS categories. While MRI-ERSPC RC outperformed PSAD and Proclarix in the overall population, Proclarix outperformed in PI-RADS ≤ 3, and no tool guaranteed 100% detection of csPCa in PI-RADS 4 and 5.

19.
Int J Biol Markers ; 37(2): 218-223, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35200058

RESUMO

Proclarix is a new blood-based test to assess the likelihood of clinically significant prostate cancer (csPCa) defined as >2 grade group. In this study, we analyzed whether Proclarix and PSA density (PSAD) could improve the selection of candidates for prostate biopsy after multiparametric magnetic resonance imaging (mpMRI). Proclarix and PSAD were assessed in 567 consecutive men with suspected PCa in whom pre-biopsy 3 Tesla mpMRI, scoring with Prostate Imaging-Report and Data System (PI-RADS) v.2, and guided and/or systematic biopsies were performed. Proclarix and PSAD thresholds having csPCa sensitivity over 90% were found at 10% and 0.07 ng/(mL*cm3), respectively. Among 100 men with negative mpMRI (PI-RADS <3), csPCa was detected in 6 cases, which would have been undetected if systematic biopsies were avoided. However, Proclarix suggested performing a biopsy on 70% of men with negative mpMRI. In contrast, PSAD only detected 50% of csPCa and required 71% of prostate biopsies. In 169 men with PI-RADS 3, Proclarix avoided 21.3% of prostate biopsies and detected all 25 cases of csPCa, while PSAD avoided 26.3% of biopsies, but missed 16% of csPCa. In 190 men with PI-RADS 4 and 108 with PI-RADS 5, Proclarix avoided 12.1% and 5.6% of prostate biopsies, but missed 4.8% and 1% of csPCa, respectively. PSAD avoided 18.4% and 9.3% of biopsies, but missed 11.4% and 4.2% csPCa, respectively. We conclude that Proclarix outperformed PSAD in the selection of candidates for prostate biopsy, especially in men with PI-RADS <3.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos
20.
Eur Urol Open Sci ; 37: 38-44, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35243388

RESUMO

BACKGROUND: Prostate Imaging-Reporting and Data System (PI-RADS) category 3 is a challenging scenario for detection of clinically significant prostate cancer (csPCa) and some tools can improve the selection of appropriate candidates for prostate biopsy. OBJECTIVE: To assess the performance of the European Randomized Study of Screening for Prostate Cancer (ERSPC) magnetic resonance imaging (MRI) model, the new Proclarix test, and prostate-specific antigen density (PSAD) in selecting candidates for prostate biopsy among men in the PI-RADS 3 category. DESIGN SETTING AND PARTICIPANTS: We conducted a head-to-head prospective analysis of 567 men suspected of having PCa for whom guided and systematic biopsies were scheduled between January 2018 and March 2020 in a single academic institution. A PI-RADS v.2 category 3 lesion was identified in 169 men (29.8%). OUTCOME MEASUREMENT AND STATISTICAL ANALYSIS: csPCa, insignificant PCa (iPCa), and unnecessary biopsy rates were analysed. csPCa was defined as grade group ≥2. Receiver operating characteristic (ROC) curves, decision curve analysis curves, and clinical utility curves were plotted. RESULTS AND LIMITATIONS: PCa was detected in 53/169 men (31.4%) with a PI-RADS 3 lesion, identified as csPCa in 25 (14.8%) and iPCa in 28 (16.6%). The area under the ROC curve for csPCa detection was 0.703 (95% confidence interval [CI] 0.621-0.768) for Proclarix, 0.657 (95% CI 0.547-0.766) for the ERSPC MRI model, and 0.612 (95% CI 0.497-0.727) for PSAD (p = 0.027). The threshold with the highest sensitivity was 10% for Proclarix, 1.5% for the ERSPC MRI model, and 0.07 ng/ml/cm3 for PSAD, which yielded sensitivity of 100%, 91%, and 84%, respectively. Some 21.3%, 26.2%, and 7.1% of biopsies would be avoided with Proclarix, PSAD, and the ERSPC MRI model, respectively. Proclarix showed a net benefit over PSAD and the ERSPC MRI model. Both Proclarix and PSAD reduced iPCa overdetection from 16.6% to 11.3%, while the ERSPC MRI model reduced iPCa overdetection to 15.4%. CONCLUSIONS: Proclarix was more accurate in selecting appropriate candidates for prostate biopsy among men in the PI-RADS 3 category when compared to PSAD and the ERSPC MRI model. Proclarix detected 100% of csPCa cases and would reduce prostate biopsies by 21.3% and iPCa overdetection by 5.3%. PATIENT SUMMARY: We compared three methods and found that the Proclarix test can optimise the detection of clinically significant prostate cancer in men with a score of 3 on the Prostate Imaging-Reporting and Data System for magnetic resonance imaging scans.

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