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1.
Drug Resist Updat ; 75: 101087, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38678745

RESUMEN

In recent years, new evidence has shown that the SOS response plays an important role in the response to antimicrobials, with involvement in the generation of clinical resistance. Here we evaluate the impact of heterogeneous expression of the SOS response in clinical isolates of Escherichia coli on response to the fluoroquinolone, ciprofloxacin. In silico analysis of whole genome sequencing data showed remarkable sequence conservation of the SOS response regulators, RecA and LexA. Despite the genetic homogeneity, our results revealed a marked differential heterogeneity in SOS response activation, both at population and single-cell level, among clinical isolates of E. coli in the presence of subinhibitory concentrations of ciprofloxacin. Four main stages of SOS response activation were identified and correlated with cell filamentation. Interestingly, there was a correlation between clinical isolates with higher expression of the SOS response and further progression to resistance. This heterogeneity in response to DNA damage repair (mediated by the SOS response) and induced by antimicrobial agents could be a new factor with implications for bacterial evolution and survival contributing to the generation of antimicrobial resistance.


Asunto(s)
Antibacterianos , Ciprofloxacina , Proteínas de Escherichia coli , Escherichia coli , Pruebas de Sensibilidad Microbiana , Rec A Recombinasas , Respuesta SOS en Genética , Respuesta SOS en Genética/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Ciprofloxacina/farmacología , Humanos , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Antibacterianos/farmacología , Rec A Recombinasas/genética , Rec A Recombinasas/metabolismo , Farmacorresistencia Bacteriana/genética , Serina Endopeptidasas/genética , Serina Endopeptidasas/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Daño del ADN/efectos de los fármacos , Secuenciación Completa del Genoma , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/tratamiento farmacológico , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Adaptación Fisiológica , Reparación del ADN/efectos de los fármacos , Proteínas de Unión al ADN
2.
Mol Cancer ; 23(1): 37, 2024 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-38374062

RESUMEN

Soft tissue sarcomas (STS) are diverse mesenchymal tumors with few therapeutic options in advanced stages. Trabectedin has global approval for treating STS patients resistant to anthracycline-based regimens. Recent pre-clinical data suggest that trabectedin's antitumor activity extends beyond tumor cells to influencing the tumor microenvironment (TME), especially affecting tumor-associated macrophages and their pro-tumoral functions. We present the phase I/II results evaluating a combination of metronomic trabectedin and low-dose cyclophosphamide on the TME in patients with advanced sarcomas. 50 patients participated: 20 in phase I and 30 in phase II. Changes in the TME were assessed in 28 patients using sequential tumor samples at baseline and day two of the cycle. Treatment notably decreased CD68 + CD163 + macrophages in biopsies from tumor lesions compared to pre-treatment samples in 9 of the 28 patients after 4 weeks. Baseline CD8 + T cell presence increased in 11 of these patients. In summary, up to 57% of patients exhibited a positive immunological response marked by reduced M2 macrophages or increased CD8 + T cells post-treatment. This positive shift in the TME correlated with improved clinical benefit and progression-free survival. This study offers the first prospective evidence of trabectedin's immunological effect in advanced STS patients, highlighting a relationship between TME modulation and patient outcomes.This study was registered with ClinicalTrial.gov, number NCT02406781.


Asunto(s)
Antineoplásicos Alquilantes , Sarcoma , Humanos , Trabectedina/uso terapéutico , Estudios Prospectivos , Antineoplásicos Alquilantes/uso terapéutico , Sarcoma/tratamiento farmacológico , Sarcoma/patología , Ciclofosfamida/uso terapéutico , Dioxoles , Microambiente Tumoral
3.
Antimicrob Agents Chemother ; 67(3): e0139222, 2023 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-36802234

RESUMEN

The suppression of the SOS response has been shown to enhance the in vitro activity of quinolones. Furthermore, Dam-dependent base methylation has an impact on susceptibility to other antimicrobials affecting DNA synthesis. Here, we investigated the interplay between these two processes, alone and in combination, in terms of antimicrobial activity. A genetic strategy was used employing single- and double-gene mutants for the SOS response (recA gene) and the Dam methylation system (dam gene) in isogenic models of Escherichia coli both susceptible and resistant to quinolones. Regarding the bacteriostatic activity of quinolones, a synergistic sensitization effect was observed when the Dam methylation system and the recA gene were suppressed. In terms of growth, after 24 h in the presence of quinolones, the Δdam ΔrecA double mutant showed no growth or delayed growth compared to the control strain. In bactericidal terms, spot tests showed that the Δdam ΔrecA double mutant was more sensitive than the ΔrecA single mutant (about 10- to 102-fold) and the wild type (about 103- to 104-fold) in both susceptible and resistant genetic backgrounds. Differences between the wild type and the Δdam ΔrecA double mutant were confirmed by time-kill assays. The suppression of both systems, in a strain with chromosomal mechanisms of quinolone resistance, prevents the evolution of resistance. This genetic and microbiological approach demonstrated the enhanced sensitization of E. coli to quinolones by dual targeting of the recA (SOS response) and Dam methylation system genes, even in a resistant strain model.


Asunto(s)
Proteínas de Escherichia coli , Quinolonas , Escherichia coli , Antibacterianos/farmacología , Respuesta SOS en Genética , Epigenoma , Proteínas de Escherichia coli/genética , Quinolonas/farmacología , Mutación/genética
4.
J Bacteriol ; 204(7): e0008822, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35758752

RESUMEN

This study characterizes a new genetic structure containing a multicopy of a blaVIM-2 variant with an A676C substitution, blaVIM-63. This gene was detected on the chromosome of two carbapenem-resistant clinical strains of Citrobacter freundii ST22 recovered from two patients, separated by a 6-month period, and previously in Pseudomonas aeruginosa ST2242 from the same hospital unit. Short-read sequencing was used to characterize the new variant in both species, and long-read sequencing was used to characterize the genome of C. freundii. On the P. aeruginosa chromosome, the blaVIM-63 gene was inserted between ISPsy 42-type sequences, flanked by an intl1 sequence, nearby aph(3')-VI, and sul1. On the C. freundii chromosome, the blaVIM-63 gene was inserted into a Tn6230-like transposon as a stable five-tandem-repeat multimer, flanked by the same intl1 as in P. aeruginosa. This structure was stable across subcultures and did not change in the presence of carbapenems. The blaVIM-63 gene was cloned into the pCR-Blunt plasmid to study antimicrobial susceptibility patterns and into pET29a for kinetic activity analysis. VIM-63 showed higher Km values than VIM-2 for ceftazidime and cefepime and higher kcat values for cefotaxime, ceftazidime, imipenem, and ertapenem, without differences in MIC values. This is the first study to describe this new variant, VIM-63, in two different species with a chromosomal location integrated into different mobile elements and the first to describe a stable multimer of a metallo-ß-lactamase. Despite the amino acid substitution, the susceptibility pattern of the new variant was similar to that of VIM-2. IMPORTANCE VIM group metallo-ß-lactamases are usually captured by IntI1 integrases. This work describes the detection for the first time of a novel, previously unknown variant of VIM-2, VIM-63. This carbapenemase has been found on the chromosome of two different species, Citrobacter freundii and Pseudomonas aeruginosa, from the same hospital. The adjacent genetic environment of the blaVIM-63 gene would indicate that the capture of this gene by IntI1 has occurred in two different genetic events in each of the species, and in one there has been a stable integration of tandem copies of this gene.


Asunto(s)
Ceftazidima , Infecciones por Pseudomonas , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Carbapenémicos/farmacología , Cromosomas/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/metabolismo , beta-Lactamasas/genética
5.
Antimicrob Agents Chemother ; 66(7): e0033422, 2022 07 19.
Artículo en Inglés | MEDLINE | ID: mdl-35762798

RESUMEN

We describe the first occurrence in Spain of community cases of CTX-M-27-producing Shigella sonnei sequence type 152 (ST152), resistant to quinolones and azithromycin. The cases included adult males and also one pediatric case. The isolates were clustered together with an Australian isolate and differed from other outbreak-causing strains in England by more than 50 alleles. They carried the blaCTX-M-27 gene on an 83-Kb F2:A-:B- plasmid, similar to that found in a British isolate.


Asunto(s)
Disentería Bacilar , Shigella sonnei , Adulto , Antibacterianos/farmacología , Australia , Niño , Células Clonales , Disentería Bacilar/tratamiento farmacológico , Disentería Bacilar/epidemiología , Humanos , Masculino , Plásmidos/genética , Shigella sonnei/genética , España/epidemiología , beta-Lactamasas/genética
6.
Int J Gynecol Cancer ; 31(11): 1476-1480, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34588215

RESUMEN

BACKGROUND: The pre-operative differential diagnosis between a uterine leiomyoma and a sarcoma can be a challenge. Available diagnostic tools have difficulty distinguishing between the two pathologies. PRIMARY OBJECTIVE: Τo evaluate the possibility of a pre-operative pathological diagnosis of atypical uterine muscle tumors by vaginal ultrasound-guided biopsy (VUGB). STUDY HYPOTHESIS: Diagnostic performance of ultrasound-guided biopsy will be capable of differentiating a leiomyoma from a sarcoma with a sensitivity of >90%. TRIAL DESIGN: A prospective multi-center interventional study will be performed at 10 tertiary French centers. Vaginal ultrasound Doppler examination and pelvic magnetic resonance imaging will be performed before surgery. VUGB will then be performed by a specialist radiologist. The biopsy will be obtained by performing transvaginal ultrasound under local anesthesia with lidocaine using a 16G needle. At least 4-5 specimens will be obtained in order to provide a histopathological diagnosis. All patients included in the study will be operated by laparotomy. All patients included in the study will be followed up for the subsequent 3 years according to their pathological results. MAJOR INCLUSION/EXCLUSION CRITERIA: All patients >35 years old diagnosed with a suspicious uterine tumor will be included. PRIMARY ENDPOINT: Sensitivity of VUGB on pathological diagnosis. SAMPLE SIZE: Considering a sensitivity of 90% (H0) as acceptable and a sensitivity of 95% (H1) as excellent, a sample size of 250 evaluable patients will be necessary to achieve 80% statistical power with a 5% type 1 statistical error. ESTIMATED DATES FOR COMPLETING ACCRUAL AND PRESENTING RESULTS: Accrual will be completed in December 2024 with results presented in December 2029. TRIAL REGISTRATION: Institutional Review Board (Ethic Committee of Paris Ile de France 6) no 2018-A02343-52.


Asunto(s)
Biopsia Guiada por Imagen/métodos , Sarcoma/diagnóstico por imagen , Ultrasonografía Intervencional/métodos , Neoplasias Uterinas/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Francia , Humanos , Leiomioma/diagnóstico por imagen , Leiomioma/patología , Imagen por Resonancia Magnética , Estudios Multicéntricos como Asunto , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Sarcoma/patología , Neoplasias Uterinas/patología
7.
Br J Cancer ; 122(6): 759-765, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32001832

RESUMEN

BACKGROUND: Few data are available on survival and predictive factors in early breast cancer (BC) patients treated with neoadjuvant endocrine therapy (NET). METHODS: This is a pooled analysis of two multicentre, randomised non-comparative phase 2 clinical trials evaluating neoadjuvant anastrozole and fulvestrant efficacy for postmenopausal HR+/HER2- breast cancer patients: HORGEN (NCT00871858) and CARMINA02 (NCT00629616) studies. RESULTS: In total, 236 patients were included in CARMINA02 and HORGEN trials. Modified intention-to-treat analysis was available for 217 patients. Median follow-up was 65.2 months. Relapse-free survival (RFS) and overall survival (OS) at 5 years were 83.7% (95% CI: 77.9-88) and 92.7% (95% CI: 88.2-95.6), respectively, with no difference between treatment arms. On univariate analysis, tumour staging (T2 vs T3-4; p = 0.0001), Ki-67 at surgery (≤10% vs >10%; p = 0.0093), pathological tumour size (pT1-2 vs pT3-4; p = 0.0012) and node status (pN negative vs positive; p = 0.007), adjuvant chemotherapy (p = 0.0167) and PEPI score (PEPI group I + II vs III; p = 0.0004) were associated with RFS. No events were observed in patients with pathological response according to the Sataloff classification. Multivariate analysis showed that preoperative endocrine prognostic index (PEPI) group III was associated with significantly worse RFS (p = 0.0069, hazard ratio = 3.33 (95% CI: 1.39-7.98)). CONCLUSIONS: Postmenopausal HR+/HER2- breast cancer patients receiving NET generally have a favourable outcome. The PEPI score identifies a subset of patients of poorer prognosis who are candidates for further additional treatment.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Terapia Neoadyuvante/métodos , Anciano , Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/patología , Femenino , Humanos , Pronóstico , Análisis de Supervivencia , Factores de Tiempo
8.
Lancet Oncol ; 20(9): 1263-1272, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31331699

RESUMEN

BACKGROUND: Desmoid tumours are locally aggressive tumours associated with substantial morbidity. No systemic treatments are approved for this disease, with methotrexate-vinblastine the only chemotherapy regimen assessed in a clinical trial setting to date. VEGF overexpression is a common feature in aggressive desmoid tumours. Pazopanib is an oral antiangiogenic agent targeting VEGF receptors 1, 2, and 3, platelet-derived growth factor receptor-like protein (PDGFR) α and ß, and c-KIT tyrosine kinases. We aimed to assess antitumour activity and safety of targeted therapy or combination chemotherapy in progressive desmoid tumours. METHODS: DESMOPAZ was a non-comparative, randomised, open-label, phase 2 trial conducted at 12 centres from the French Sarcoma Group. We enrolled adults (≥18 years) with progressive desmoid tumours, normal organ function and centrally documented progressive disease according to Response Evaluation Criteria in Solid Tumors version 1.1 based on two imaging assessments obtained within less than a 6-month interval. Participants were randomly assigned (2:1) to oral pazopanib 800 mg per day for up to 1 year or to an intravenous regimen combining vinblastine (5 mg/m2 per dose) and methotrexate (30 mg/m2 per dose), administered weekly for 6 months and then every other week for 6 months. Randomisation was stratified according to inclusion centre and tumour location. The primary endpoint was the proportion of patients who had not progressed at 6 months in the first 43 patients who had received one complete or two incomplete cycles of pazopanib. This endpoint was also assessed as a prespecified exploratory endpoint in all patients who had received one complete or two incomplete cycles of methotrexate-vinblastane. Safety analyses were done for all patients who received at least one dose of allocated treatment. This trial was registered with ClinicalTrials.gov, number NCT01876082. FINDINGS: From Dec 4, 2012, to Aug 18, 2017, 72 patients were enrolled and randomly assigned (n=48 in the pazopanib group; n=24 in the methotrexate-vinblastine group). Median follow-up was 23·4 months (IQR 17·1-25·5). 46 patients in the pazopanib group and 20 patients in the methotrexate-vinblastine group were assessable for activity. In the first 43 patients assessable for the primary endpoint in the pazopanib group, the proportion of patients who had not progressed at 6 months was 83·7% (95% CI 69·3-93·2). The proportion of patients treated with methotrexate-vinblastine who had not progressed at 6 months was 45·0% (95% CI 23·1-68·5). The most common grade 3 or 4 adverse events in the pazopanib group were hypertension (n=10, 21%) and diarrhoea (n=7, 15%) and in the methotrexate-vinblastine group were neutropenia (n=10, 45%) and liver transaminitis (n=4, 18%). 11 patients (23%) had at least one serious adverse event related to study treatment in the pazopanib group, as did and six patients (27%) in the methotrexate-vinblastine group. INTERPRETATION: Pazopanib has clinical activity in patients with progressive desmoid tumours and could be a valid treatment option in this rare and disabling disease. FUNDING: GlaxoSmithKline and Novartis.


Asunto(s)
Fibromatosis Agresiva/tratamiento farmacológico , Metotrexato/administración & dosificación , Pirimidinas/administración & dosificación , Sulfonamidas/administración & dosificación , Vinblastina/administración & dosificación , Adolescente , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Femenino , Fibromatosis Agresiva/patología , Humanos , Indazoles , Masculino , Metotrexato/efectos adversos , Persona de Mediana Edad , Supervivencia sin Progresión , Pirimidinas/efectos adversos , Sulfonamidas/efectos adversos , Resultado del Tratamiento , Vinblastina/efectos adversos , Adulto Joven
9.
J Biol Chem ; 292(22): 9075-9087, 2017 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-28373284

RESUMEN

Pathogenic Acinetobacter species, including Acinetobacter baumannii and Acinetobacter nosocomialis, are opportunistic human pathogens of increasing relevance worldwide. Although their mechanisms of drug resistance are well studied, the virulence factors that govern Acinetobacter pathogenesis are incompletely characterized. Here we define the complete secretome of A. nosocomialis strain M2 in minimal medium and demonstrate that pathogenic Acinetobacter species produce both a functional type I secretion system (T1SS) and a contact-dependent inhibition (CDI) system. Using bioinformatics, quantitative proteomics, and mutational analyses, we show that Acinetobacter uses its T1SS for exporting two putative T1SS effectors, an Repeats-in-Toxin (RTX)-serralysin-like toxin, and the biofilm-associated protein (Bap). Moreover, we found that mutation of any component of the T1SS system abrogated type VI secretion activity under nutrient-limited conditions, indicating a previously unrecognized cross-talk between these two systems. We also demonstrate that the Acinetobacter T1SS is required for biofilm formation. Last, we show that both A. nosocomialis and A. baumannii produce functioning CDI systems that mediate growth inhibition of sister cells lacking the cognate immunity protein. The Acinetobacter CDI systems are widely distributed across pathogenic Acinetobacter species, with many A. baumannii isolates harboring two distinct CDI systems. Collectively, these data demonstrate the power of differential, quantitative proteomics approaches to study secreted proteins, define the role of previously uncharacterized protein export systems, and observe cross-talk between secretion systems in the pathobiology of medically relevant Acinetobacter species.


Asunto(s)
Acinetobacter baumannii/metabolismo , Acinetobacter baumannii/patogenicidad , Proteínas Bacterianas/metabolismo , Sistemas de Secreción Bacterianos/metabolismo , Acinetobacter baumannii/genética , Proteínas Bacterianas/genética , Sistemas de Secreción Bacterianos/genética , Humanos
10.
BMC Cancer ; 18(1): 194, 2018 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-29454321

RESUMEN

BACKGROUND: Bladder cancer is the 7th cause of death from cancer in men and 10th in women. Metastatic patients have a poor prognosis with a median overall survival of 14 months. Until recently, vinflunine was the only second-line chemotherapy available for patients who relapse. Deregulation of the PI3K/AKT/mTOR pathway was observed in more than 40% of bladder tumors and suggested the use of mTOR as a target for the treatment of urothelial cancers. METHODS: This trial assessed the efficacy of temsirolimus in a homogenous cohort of patients with recurrent or metastatic bladder cancer following first-line chemotherapy. Efficacy was measured in terms of non-progression at two months according to the RECIST v1.1 criteria. Based on a two-stage optimal Simon's design, 15 non-progressions out of 51 evaluable patients were required to claim efficacy. Patients were treated at a weekly dose of 25 mg IV until progression, unacceptable toxicities or withdrawal. RESULTS: Among the 54 patients enrolled in the study between November 2009 and July 2014, 45 were assessable for the primary efficacy endpoint. A total of 22 (48.9%) non-progressions were observed at 2 months with 3 partial responses and 19 stable diseases. Remarkably, 4 patients were treated for more than 30 weeks. Fifty patients experienced at least a related grade1/2 (94%) and twenty-eight patients (52.8%) a related grade 3/4 adverse event. Eleven patients had to stop treatment for toxicity. This led to recruitment being halted by an independent data monitoring committee with regard to the risk-benefit balance and the fact that the primary objective was already met. CONCLUSIONS: While the positivity of this trial indicates a potential benefit of temsirolimus for a subset of bladder cancer patients who are refractory to first line platinum-based chemotherapy, the risk of adverse events associated with the use of this mTOR inhibitor would need to be considered when such an option is envisaged in this frail population of patients. It also remains to identify patients who will benefit the most from this targeted therapy. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01827943 (trial registration date: October 29, 2012); Retrospectively registered.


Asunto(s)
Antineoplásicos/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Sirolimus/análogos & derivados , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Tomografía Computarizada por Tomografía de Emisión de Positrones , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/efectos adversos , Retratamiento , Sirolimus/administración & dosificación , Sirolimus/efectos adversos , Sirolimus/uso terapéutico , Resultado del Tratamiento , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/mortalidad
11.
Antimicrob Agents Chemother ; 60(8): 5076-9, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27270288

RESUMEN

LpxC inhibitors have generally shown poor in vitro activity against Acinetobacter baumannii We show that the LpxC inhibitor PF-5081090 inhibits lipid A biosynthesis, as determined by silver staining and measurements of endotoxin levels, and significantly increases cell permeability. The presence of PF-5081090 at 32 mg/liter increased susceptibility to rifampin, vancomycin, azithromycin, imipenem, and amikacin but had no effect on susceptibility to ciprofloxacin and tigecycline. Potentiating existing antibiotics with LpxC inhibitors may represent an alternative treatment strategy for multidrug-resistant A. baumannii.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/metabolismo , Antibacterianos/farmacología , Carbapenémicos/farmacología , Infecciones por Acinetobacter/microbiología , Amidohidrolasas/antagonistas & inhibidores , Amidohidrolasas/metabolismo , Amicacina/farmacología , Azitromicina/farmacología , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/metabolismo , Farmacorresistencia Bacteriana Múltiple , Imipenem/farmacología , Pruebas de Sensibilidad Microbiana , Minociclina/análogos & derivados , Minociclina/farmacología , Rifampin/farmacología , Tigeciclina , Vancomicina/farmacología
12.
Br J Cancer ; 113(4): 585-94, 2015 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-26171933

RESUMEN

BACKGROUND: The aim of this study was to assess the efficacy of neoadjuvant anastrozole and fulvestrant treatment of large operable or locally advanced hormone-receptor-positive breast cancer not eligible for initial breast-conserving surgery, and to identify genomic changes occurring after treatment. METHODS: One hundred and twenty post-menopausal patients were randomised to receive 1 mg anastrozole (61 patients) or 500 mg fulvestrant (59 patients) for 6 months. Genomic DNA copy number profiles were generated for a subgroup of 20 patients before and after treatment. RESULTS: A total of 108 patients were evaluable for efficacy and 118 for toxicity. The objective response rate determined by clinical palpation was 58.9% (95% CI=45.0-71.9) in the anastrozole arm and 53.8% (95% CI=39.5-67.8) in the fulvestrant arm. The breast-conserving surgery rate was 58.9% (95% CI=45.0-71.9) in the anastrozole arm and 50.0% (95% CI=35.8-64.2) in the fulvestrant arm. Pathological responses >50% occurred in 24 patients (42.9%) in the anastrozole arm and 13 (25.0%) in the fulvestrant arm. The Ki-67 score fell after treatment but there was no significant difference between the reduction in the two arms (anastrozole 16.7% (95% CI=13.3-21.0) before, 3.2% (95% CI=1.9-5.5) after, n=43; fulvestrant 17.1% (95%CI=13.1-22.5) before, 3.2% (95% CI=1.8-5.7) after, n=38) or between the reduction in Ki-67 in clinical responders and non-responders. Genomic analysis appeared to show a reduction of clonal diversity following treatment with selection of some clones with simpler copy number profiles. CONCLUSIONS: Both anastrozole and fulvestrant were effective and well-tolerated, enabling breast-conserving surgery in over 50% of patients. Clonal changes consistent with clonal selection by the treatment were seen in a subgroup of patients.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Estradiol/análogos & derivados , Nitrilos/uso terapéutico , Posmenopausia/efectos de los fármacos , Triazoles/uso terapéutico , Anciano , Anciano de 80 o más Años , Anastrozol , Estradiol/uso terapéutico , Femenino , Fulvestrant , Humanos , Persona de Mediana Edad
13.
Antimicrob Agents Chemother ; 58(5): 2972-5, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24566189

RESUMEN

Acinetobacter baumannii can acquire resistance to the cationic peptide antibiotic colistin through complete loss of lipopolysaccharide (LPS) expression. The activities of the host cationic antimicrobials LL-37 and human lysozyme against multidrug-resistant clinical isolates of A. baumannii that acquired colistin resistance through lipopolysaccharide loss were characterized. We demonstrate that LL-37 has activity against strains lacking lipopolysaccharide that is similar to that of their colistin-sensitive parent strains, whereas human lysozyme has increased activity against colistin-resistant strains lacking LPS.


Asunto(s)
Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/metabolismo , Antiinfecciosos/farmacología , Colistina/farmacología , Lipopolisacáridos/metabolismo , Farmacorresistencia Bacteriana Múltiple , Pruebas de Sensibilidad Microbiana
14.
Oncologist ; 19(12): 1227-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25355844

RESUMEN

BACKGROUND: Preclinical studies demonstrated that non-nucleoside reverse transcriptase inhibitors used for the treatment of HIV could antagonize tumor development. This led us to assess the efficacy of efavirenz in patients with metastatic castration-resistant prostate cancer (mCRPC) in a multicenter phase II study. METHODS: We used a Simon two-stage design and a 3-month prostate-specific antigen (PSA) nonprogression rate of 40% as a primary objective. Patients received 600 mg efavirenz daily with the possibility of a dose increase in case of PSA progression. Exploratory analyses included pharmacokinetics of efavirenz plasma concentrations and correlations with clinical outcomes. RESULTS: Among 53 assessable patients, we observed 15 instances of PSA nonprogression at 3 months, corresponding to a nonprogression rate of 28.3% (95% confidence interval: 16.8%-42.3%). The exploratory analysis revealed that for the 7 patients in whom optimal plasma concentration of efavirenz was achieved, PSA progression was observed in only 28.6% compared with 81.8% of patients with suboptimal plasma concentrations of efavirenz. CONCLUSION: Although 600 mg efavirenz did not statistically improve the PSA nonprogression rate, our exploratory analysis suggests that higher plasma concentrations of this drug (i.e., use of increased dosages) may be of potential benefit for the treatment of mCRPC.


Asunto(s)
Benzoxazinas/uso terapéutico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Adulto , Alquinos , Benzoxazinas/farmacocinética , Ciclopropanos , Progresión de la Enfermedad , Humanos , Masculino , Antígeno Prostático Específico/sangre , Resultado del Tratamiento
15.
Artículo en Inglés | MEDLINE | ID: mdl-38913264

RESUMEN

Hospital sewage is an ecosystem that facilitates the transfer of antibiotic and heavy metal resistance genes and the interaction of human and environmental bacteria. In this environment, we have detected the presence of 7 KPC-2 and BEL-1 co-producing E. coli isolates of two different clones over a 10-month period in the same hospital. All isolates carried blaKPC-2 and the operon mer on the same IncP plasmid of similar size and an IncN plasmid of different size each clone carrying blaBEL-1. Both IncN-blaBEL-1 plasmids shared a 77 kb region containing blaBEL-1 alongside with fosE, bla OXA-10 and aac(6')-1b genes in a class 3 integron within a Tn3 transposon. The major IncN plasmid contained in addition a region homolog to P1-like bacteriophage RCS47, including the lytic RepL and lysogenic proteins, but other phage regions were incomplete. The characters such as the temporal persistence in sewage, the absence of colonized patients in the hospital or in the region, the presence of a p1 phage-plasmid fusion and the infrequent class 3 integron as genetic platform would indicate that BEL-1-producing isolates could have been generated in situ by adaptation to human sewage. Part of the microbiota in these discharges could be explained by the interactions of sewage ecosystems and not derive directly from the hospital.

16.
J Antimicrob Chemother ; 68(12): 2710-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23818283

RESUMEN

Antimicrobial susceptibility testing is essential for guiding the treatment of many types of bacterial infections, especially in the current context of rising rates of antibiotic resistance. The most commonly employed methods rely on the detection of phenotypic resistance by measuring bacterial growth in the presence of the antibiotic being tested. Although these methods are highly sensitive for the detection of resistance, they require that the bacterial pathogen is isolated from the clinical sample before testing and must employ incubation times that are sufficient for differentiating resistant from susceptible isolates. Knowledge regarding the molecular determinants of antibiotic resistance has facilitated the development of novel approaches for the rapid detection of resistance in bacterial pathogens. PCR-based techniques, mass spectrometry, microarrays, microfluidics, cell lysis-based approaches and whole-genome sequencing have all demonstrated the ability to detect resistance in various bacterial species. However, it remains to be determined whether these methods can achieve sufficient sensitivity and specificity compared with standard phenotypic resistance testing to justify their use in routine clinical practice. In the present review, we discuss recent progress in the development of methods for rapid antimicrobial susceptibility testing and highlight the limitations of each approach that still remain be addressed.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Infecciones Bacterianas/microbiología , Pruebas de Sensibilidad Microbiana/métodos , Pruebas de Sensibilidad Microbiana/tendencias , Infecciones Bacterianas/tratamiento farmacológico , Humanos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/tendencias
17.
Eur J Nucl Med Mol Imaging ; 40(12): 1817-27, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24042540

RESUMEN

PURPOSE: To assess diagnostic accuracy of (18)F-FDG PET/CT at 3 months for the detection of local recurrence after radiofrequency ablation (RFA) of lung metastases. METHODS: The PET/CT scan at 3 months was compared with a baseline PET/CT scan from a maximum of 2 months before RFA, with the reference standard as recurrence diagnosed by CT during a 12-month follow-up. Local recurrence was diagnosed on the PET/CT scan if lesional uptake was greater than the mediastinal background. Maximum standardized uptake values (SUVmax) were recorded. ROC curve analysis for SUVmax was performed. Overall survival (OS) and time to local relapse were computed from the date of RFA using the Kaplan-Meier method (www.clinicaltrials.gov: NCT 00382252). RESULTS: Between 2005 and 2009, 89 patients (mean age 65 years) underwent RFA for 115 lung metastases (mean size 16.2 ± 6.9 mm). The median SUVmax before RFA was 5.8 ± 4. PET/CT at 3 months and the reference standard were available in 77 patients and 100 lesions. Accuracy was 66.00% (95% CI 55.85-75.18%), sensitivity 90.91% (95 % CI 58.72-99.77 %), specificity 62.92% (95% CI 52.03-72.93%), PPV 23.26% (95% CI 11.76-38.63%), and NPV 98.25% (95% CI 90.61-99.96%). One-year OS was 94.2% (95% CI 86.6-97.5%) and the probability of being free of local recurrence 1 year after RFA was 84.6% (95% CI 75.0-90.8%). CONCLUSION: The specificity of PET/CT at 3 months is low because of persistent inflammation, especially when the lesion is close to the pleura. This technique is useful for its negative predictive value, but positive findings need to be confirmed by histology before new treatment is planned.


Asunto(s)
Técnicas de Ablación , Fluorodesoxiglucosa F18 , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/secundario , Tomografía de Emisión de Positrones , Terapia por Radiofrecuencia , Tomografía Computarizada por Rayos X , Técnicas de Ablación/efectos adversos , Anciano , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Masculino , Imagen Multimodal , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Curva ROC , Ondas de Radio/efectos adversos , Estándares de Referencia , Análisis de Supervivencia , Resultado del Tratamiento
18.
Mol Cell Proteomics ; 10(11): M111.008094, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21828285

RESUMEN

Lipodystrophy is a major disease involving severe alterations of adipose tissue distribution and metabolism. Mutations in genes encoding the nuclear envelope protein lamin A or its processing enzyme, the metalloproteinase Zmpste24, cause diverse human progeroid syndromes that are commonly characterized by a selective loss of adipose tissue. Similarly to humans, mice deficient in Zmpste24 accumulate prelamin A and display phenotypic features of accelerated aging, including lipodystrophy. Herein, we report the proteome and phosphoproteome of adipose tissue as well as serum metabolome in lipodystrophy by using Zmpste24(-/-) mice as experimental model. We show that Zmpste24 deficiency enhanced lipolysis, fatty acid biogenesis and ß-oxidation as well as decreased fatty acid re-esterification, thus pointing to an increased partitioning of fatty acid toward ß-oxidation and away from storage that likely underlies the observed size reduction of Zmpste24-null adipocytes. Besides the mitochondrial proteins related to lipid metabolism, other protein networks related to mitochondrial function, including those involved in tricarboxylic acid cycle and oxidative phosphorylation, were up-regulated in Zmpste24(-/-) mice. These results, together with the observation of an increased mitochondrial response to oxidative stress, support the relationship between defective prelamin A processing and mitochondrial dysfunction and highlight the relevance of oxidative damage in lipoatrophy and aging. We also show that absence of Zmpste24 profoundly alters the processing of the cytoskeletal protein vimentin and identify a novel protein dysregulated in lipodystrophy, High-Mobility Group Box-1 Protein. Finally, we found several lipid derivates with important roles in energy balance, such as Lysophosphatidylcholine or 2-arachidonoylglycerol, to be dysregulated in Zmpste24(-/-) serum. Together, our findings in Zmpste24(-/-) mice may be useful to unveil the mechanisms underlying adipose tissue dysfunction and its overall contribution to body homeostasis in progeria and other lipodystrophy syndromes as well as to develop novel strategies to prevent or ameliorate these diseases.


Asunto(s)
Envejecimiento Prematuro/metabolismo , Lipodistrofia/metabolismo , Proteínas de la Membrana/genética , Metaloendopeptidasas/genética , Mitocondrias/metabolismo , Proteoma/metabolismo , Vimentina/metabolismo , Envejecimiento Prematuro/genética , Animales , Biomarcadores/sangre , Glucemia/metabolismo , Regulación de la Expresión Génica , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Grasa Intraabdominal/metabolismo , Grasa Intraabdominal/patología , Lamina Tipo A , Metabolismo de los Lípidos , Lípidos/sangre , Lipodistrofia/genética , Masculino , Metaboloma , Ratones , Ratones Noqueados , Mitocondrias/enzimología , Proteínas Nucleares/metabolismo , Oxidación-Reducción , Fosfoproteínas/metabolismo , Mapas de Interacción de Proteínas , Precursores de Proteínas/metabolismo , Proteoma/genética
19.
Int J Antimicrob Agents ; 61(2): 106721, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36642235

RESUMEN

RecA inhibition could be an important strategy to combat antimicrobial resistance because of its key role in the SOS response, DNA repair and homologous recombination contributing to bacterial survival. This study evaluated the impact of RecA inactivation on heteroresistance in clinical isolates of Escherichia coli and their corresponding recA-deficient isogenic strains to multiple classes of antimicrobial agents. A high frequency (>30%) of heteroresistance was observed in this collection of clinical isolates. Deletion of the recA gene led to a marked reduction in heteroresistant subpopulations, especially against quinolones or ß-lactams. The molecular basis of heteroresistance was associated with an increase in copy number of plasmid-borne resistance genes (blaTEM-1B) or tandem gene amplifications (qnrA1). Of note, in the absence of the recA gene, the increase in copy number of resistance genes was suppressed. This makes the recA gene a promising target for combating heteroresistance.


Asunto(s)
Escherichia coli , Quinolonas , Escherichia coli/genética , Plásmidos/genética , Reparación del ADN
20.
J Hematol Oncol ; 15(1): 157, 2022 10 27.
Artículo en Inglés | MEDLINE | ID: mdl-36303228

RESUMEN

Soft tissue sarcomas (STS) are heterogeneous mesenchymal tumors with limited therapeutic options in the advanced setting. Immune checkpoint inhibitors have been shown to have significant clinical activity in inflamed STS which are characterized by the presence of tertiary lymphoid structures (TLS). New strategies are needed to sensitize TLS-negative STS to immunotherapy. Engagement of the toll-Like Receptor 4 (TLR4) signal pathway contributes to the development of a favorable tumor microenvironment in solid tumors. G100 is a highly potent toll-like receptor 4 (TLR4) agonist. We hypothesized that intra-tumoral G100 would induce a robust local and potentially systemic anti-tumor immune response in the microenvironment of TLS-negative sarcoma, leading to improved response to PD1 inhibition. Twenty metastatic STS patients who had a superficial injectable lesion were treated with 50 mg of cyclophosphamide (CP) orally twice daily (1 week on and 1 week off), 200 mg of pembrolizumab intravenously on day 8 of a planned 21-day cycle and G100 20 µg one weekly intra-tumoral injection for at least 6 weeks and for a maximum of 12 weeks (1st injection one week before CP administration, ie. Day -7). Biopsies and blood were collected pre and post treatment. Of the 17 patients assessable for efficacy analysis, 2 were progression-free at 6 months, and the 6-month non-progression rate was 11.8% (95% CI: 1.5-36.4), indicating that the first endpoint of the study was not reached. In 8 patients, there was an increase in T-cell infiltration into tumor after treatment. The ratio CD8/Fox-P3 + CD4 on treatment decreased in 11 cases out of 14 suggesting a predominant induction of Treg. Soluble PDL1 levels at baseline were also with adverse outcome. G100 appears to modulate the tumor microenvironment with significant infiltration of T cells. However, clinical activity in combination with PD1 inhibition was limited and no clear correlation was observed between tumor shrinkage and increased inflammation. TLR4 stimulation might have both antitumor and pro-tumor consequences.Trial registration: This study was registered with ClinicalTrial.gov, number NCT02406781.


Asunto(s)
Sarcoma , Receptor Toll-Like 4 , Humanos , Anticuerpos Monoclonales Humanizados , Ciclofosfamida , Sarcoma/tratamiento farmacológico , Sarcoma/patología , Receptor Toll-Like 4/uso terapéutico , Microambiente Tumoral , Estudios Clínicos como Asunto
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