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1.
Hum Pathol ; 148: 14-22, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38688412

RESUMO

Mullerian adenosarcoma is a rare malignant biphasic tumor. The mesenchymal component may be low or high grade, with or without sarcomatous overgrowth (SO). Little is known about the molecular heterogeneity of these tumors. In this study, we aim to reclassify a large retrospective monocentric cohort of uterine adenosarcomas according to tumor grade and SO, to evaluate the clinical significance of pathological classification and to correlate with copy-number variations inferred from single nucleotide polymorphism array. Of the 67 uterine adenosarcomas, 18 (26.9%) were low grade without SO, 7 (10.4%) low grade with SO, 8 (11.9%) high grade without SO and 34 (50.7%) high grade with SO. SO, necrosis and RMS were more frequent in high grade than low grade adenosarcomas (p < 0.001). Low-rank test showed that recurrence-free survival was significantly shortened in high grade than low grade adenosarcomas (p = 0.035) and SO was associated with shortened overall and recurrence-free survival (p = 0.038 and p = 0.009, respectively). High-grade tumors displayed complex genomic profiles with multiple segmental losses including TP53, ATM and PTEN genes. The median genomic index was significantly higher in high grade than low grade tumors (27 [3-60] vs 5,3 [0-16], p < 0.0001) and was significantly higher in presence of SO in low grade tumors (12,8 [10-16] vs 2,6 [0-10], p = 0.0006). We propose to report sarcomatous overgrowth with the tumor grade for prognostication in adenosarcoma and representative sampling is crucial for evaluation of these histological criteria.

2.
Clin Cancer Res ; 29(9): 1822-1831, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36805183

RESUMO

PURPOSE: We compared the mutational profile of second breast cancers (SBC) following first ipislateral hormone receptor-positive breast cancers of patient-matched tumors to distinguish new primaries from true recurrences. EXPERIMENTAL DESIGN: Targeted next-generation sequencing using the Oncomine Tumor Mutation Load Assay. Variants were filtered according to their allele frequency ≥ 5%, read count ≥ 5X, and genomic effect and annotation. Whole genome comparative genomic hybridization array (CGH) was also performed to evaluate clonality. RESULTS: Among the 131 eligible patients, 96 paired first breast cancer (FBC) and SBC were successfully sequenced and analyzed. Unshared variants specific to the FBC and SBC were identified in 71.9% and 61.5%, respectively. Paired samples exhibited similar frequency of gene variants, median number of variants per sample, and variant allele frequency of the reported variants except for GATA3. Among the 30 most frequent gene alterations, ARIDIA, NSD2, and SETD2 had statistically significant discordance rates in paired samples. Seventeen paired samples (17.7%) exhibited common variants and were considered true recurrences; these patients had a trend for less favorable survival outcomes. Among the 8 patients with available tissue for CGH analysis and considered new primaries by comparison of the mutation profiles, 4 patients had clonally related tumors. CONCLUSIONS: Patient-matched FBC and SBC analysis revealed that only a minority of patients exhibited common gene variants between the first and second tumor. Further analysis using larger cohorts, preferably using single-cell analyses to account for clonality, might better select patients with true recurrences and thereby better inform the decision-making process.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Hibridização Genômica Comparativa , Mutação , Genômica , Recidiva
3.
Nature ; 610(7931): 343-348, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36071165

RESUMO

Cancer progression is driven in part by genomic alterations1. The genomic characterization of cancers has shown interpatient heterogeneity regarding driver alterations2, leading to the concept that generation of genomic profiling in patients with cancer could allow the selection of effective therapies3,4. Although DNA sequencing has been implemented in practice, it remains unclear how to use its results. A total of 1,462 patients with HER2-non-overexpressing metastatic breast cancer were enroled to receive genomic profiling in the SAFIR02-BREAST trial. Two hundred and thirty-eight of these patients were randomized in two trials (nos. NCT02299999 and NCT03386162) comparing the efficacy of maintenance treatment5 with a targeted therapy matched to genomic alteration. Targeted therapies matched to genomics improves progression-free survival when genomic alterations are classified as level I/II according to the ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT)6 (adjusted hazards ratio (HR): 0.41, 90% confidence interval (CI): 0.27-0.61, P < 0.001), but not when alterations are unselected using ESCAT (adjusted HR: 0.77, 95% CI: 0.56-1.06, P = 0.109). No improvement in progression-free survival was observed in the targeted therapies arm (unadjusted HR: 1.15, 95% CI: 0.76-1.75) for patients presenting with ESCAT alteration beyond level I/II. Patients with germline BRCA1/2 mutations (n = 49) derived high benefit from olaparib (gBRCA1: HR = 0.36, 90% CI: 0.14-0.89; gBRCA2: HR = 0.37, 90% CI: 0.17-0.78). This trial provides evidence that the treatment decision led by genomics should be driven by a framework of target actionability in patients with metastatic breast cancer.


Assuntos
Neoplasias da Mama , Tomada de Decisão Clínica , Genoma Humano , Genômica , Metástase Neoplásica , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Tomada de Decisão Clínica/métodos , Análise Mutacional de DNA , Progressão da Doença , Feminino , Genes BRCA1 , Genes BRCA2 , Genoma Humano/genética , Humanos , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Ftalazinas/uso terapêutico , Piperazinas/uso terapêutico
4.
Clin Cancer Res ; 28(18): 4018-4026, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35802649

RESUMO

PURPOSE: Targeted therapies (TT) and immune checkpoint blockers (ICB) have revolutionized the approach to non-small cell lung cancer (NSCLC) treatment in the era of precision medicine. Their impact as switch maintenance therapy based on molecular characterization is unknown. PATIENTS AND METHODS: SAFIR02-Lung/IFCT 1301 was an open-label, randomized, phase II trial, involving 33 centers in France. We investigated eight TT (substudy-1) and one ICB (substudy-2), compared with standard-of-care as a maintenance strategy in patients with advanced EGFR, ALK wild-type (wt) NSCLC without progression after first-line chemotherapy, based on high-throughput genome analysis. The primary outcome was progression-free survival (PFS). RESULTS: Among the 175 patients randomized in substudy-1, 116 received TT (selumetinib, vistusertib, capivasertib, AZD4547, AZD8931, vandetanib, olaparib, savolitinib) and 59 standard-of-care. Median PFS was 2.7 months [95% confidence interval (CI), 1.6-2.9] with TT versus 2.7 months (1.6-4.1) with standard-of-care (HR, 0.97; 95% CI, 0.7-1.36; P = 0.87). There were no significant differences in PFS within any molecular subgroup. In substudy-2, 183 patients were randomized, 121 received durvalumab and 62 standard-of-care. Median PFS was 3.0 months (2.3-4.4) with durvalumab versus 3.0 months (2.0-5.1) with standard-of-care (HR, 0.86; 95% CI, 0.62-1.20; P = 0.38). Preplanned subgroup analysis showed an enhanced benefit with durvalumab in patients with PD-L1 tumor proportion score (TPS) ≥1%, (n = 29; HR, 0.29; 95% CI, 0.11-0.75) as compared with PD-L1 <1% (n = 31; HR, 0.71; 95% CI, 0.31-1.60; Pinteraction = 0.036). CONCLUSIONS: Molecular profiling can feasibly be implemented to guide treatment choice for the maintenance strategy in EGFR/ALK wt NSCLC; in this study it did not lead to substantial treatment benefits beyond durvalumab for PD-L1 ≥ 1 patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno B7-H1/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Medicina de Precisão , Receptores Proteína Tirosina Quinases/genética
5.
Lung Cancer ; 169: 31-39, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35609409

RESUMO

INTRODUCTION: Lung cancer remains the most frequent cause of brain metastases (BMs) and is responsible for high morbidity and mortality. Intracranial response to systemic treatments is inconsistent due to several mechanisms: genomic heterogeneity, blood-tumor barrier, and the brain-specific microenvironment. We conducted a study using data from the SAFIR02-LUNG trial. The primary objective was to compare the molecular profiles of non-small-cell lung cancer (NSCLC) with or without BMs. The secondary objective was to explore central nervous system (CNS) outcomes with various maintenance treatment regimens. METHODS: In total, 365 patients harboring interpretable molecular data were included in this analysis. Clinical and biological data were collected. Genomic analyses were based on array-comparative genomic hybridization and next-generation sequencing (NGS) following the trial recommendations. RESULTS: Baseline genomic analyses of copy number variations identified a 24-gene signature specific to lung cancer BM occurrence, all previously known to take part in oncogenesis. NGS analysis identified a higher proportion of KRAS mutations in the BM-positive group (44.3% versus 32.3%), especially G12C mutations (63% versus 47%). Protein interaction analyses highlighted several functional interactions centered on EGFR. Furthermore, the risk of CNS progression was decreased with standard pemetrexed maintenance therapy. The highest rate of CNS progression was observed with durvalumab, probably because of the specific intracranial immune microenvironment. CONCLUSION: This work identified a 24-gene signature specific to lung cancer with BM. Further studies are needed to precisely determine the functional implications of these genes to identify new therapeutic targets for the treatment of lung cancer with BM.


Assuntos
Neoplasias Encefálicas , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Hibridização Genômica Comparativa , Variações do Número de Cópias de DNA , Humanos , Pulmão/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Ensaios Clínicos Controlados Aleatórios como Assunto , Microambiente Tumoral/genética
6.
Cancer Res ; 81(9): 2470-2480, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33685991

RESUMO

PI3Kα inhibitors have shown clinical activity in PIK3CA-mutated estrogen receptor-positive (ER+) patients with breast cancer. Using whole genome CRISPR/Cas9 sgRNA knockout screens, we identified and validated several negative regulators of mTORC1 whose loss confers resistance to PI3Kα inhibition. Among the top candidates were TSC1, TSC2, TBC1D7, AKT1S1, STK11, MARK2, PDE7A, DEPDC5, NPRL2, NPRL3, C12orf66, SZT2, and ITFG2. Loss of these genes invariably results in sustained mTOR signaling under pharmacologic inhibition of the PI3K-AKT pathway. Moreover, resistance could be prevented or overcome by mTOR inhibition, confirming the causative role of sustained mTOR activity in limiting the sensitivity to PI3Kα inhibition. Cumulatively, genomic alterations affecting these genes are identified in about 15% of PIK3CA-mutated breast tumors and appear to be mutually exclusive. This study improves our understanding of the role of mTOR signaling restoration in leading to resistance to PI3Kα inhibition and proposes therapeutic strategies to prevent or revert this resistance. SIGNIFICANCE: These findings show that genetic lesions of multiple negative regulators of mTORC1 could limit the efficacy of PI3Kα inhibitors in breast cancer, which may guide patient selection strategies for future clinical trials.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Mutação com Perda de Função , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/administração & dosagem , Transdução de Sinais/genética , Tiazóis/administração & dosagem , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Sobrevivência Celular/efeitos dos fármacos , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Estudos de Coortes , Feminino , Células HEK293 , Humanos , Células MCF-7 , Camundongos , Serina-Treonina Quinases TOR/metabolismo , Transdução Genética , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Nat Med ; 27(2): 250-255, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33462450

RESUMO

The impact of single-agent antibodies against programmed death-ligand 1 (PD-L1) as maintenance therapy is unknown in patients with metastatic breast cancer. The SAFIR02-BREAST IMMUNO substudy included patients with human epidermal growth factor receptor type 2 (Her2)-negative metastatic breast cancer whose disease did not progress after six to eight cycles of chemotherapy. Patients (n = 199) were randomized to either durvalumab (10 mg kg-1 every 2 weeks) or maintenance chemotherapy. In the overall population, durvalumab did not improve progression-free survival (adjusted hazard ratio (HR): 1.40, 95% confidence interval (CI): 1.00-1.96; P = 0.047) or overall survival (OS; adjusted HR: 0.84, 95% CI: 0.54-1.29; P = 0.423). In an exploratory subgroup analysis, durvalumab improved OS in patients with triple-negative breast cancer (TNBC; n = 82; HR: 0.54, 95% CI: 0.30-0.97, P = 0.0377). Exploratory analysis showed that the HR of death was 0.37 (95% CI: 0.12-1.13) for patients with PD-L1+ TNBC (n = 32) and 0.49 (95% CI: 0.18-1.34) for those with PD-L1- TNBC (n = 29). In patients with TNBC, exploratory analyses showed that the HR for durvalumab efficacy (OS) was 0.18 (95% CI: 0.05-0.71; log-rank test, P = 0.0059) in patients with CD274 gain/amplification (n = 23) and 1.12 (95% CI: 0.42-2.99; log-rank test, P = 0.8139) in patients with CD274 normal/loss (n = 32). Tumor infiltration by lymphocytes (CD8, FoxP3 and CD103 expressions) and homologous recombination deficiency did not predict sensitivity to durvalumab in exploratory analyses. This latter finding should be interpreted with caution since only one patient presented a germline BRCA mutation. The present study provides a rationale to evaluate single-agent durvalumab in maintenance therapy in patients with TNBC. Exploratory analyses identified CD274 amplification as a potential biomarker of sensitivity. Maintenance chemotherapy was more effective than durvalumab in patients with hormone receptor-positive and Her2-negative disease.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Antígeno B7-H1/genética , Mama/efeitos dos fármacos , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Quimioterapia de Manutenção/métodos , Pessoa de Meia-Idade , Metástase Neoplásica , Intervalo Livre de Progressão , Receptor ErbB-2/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia
8.
Nat Microbiol ; 6(3): 327-338, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33349664

RESUMO

Bloodstream infections caused by nontyphoidal Salmonella are a major public health concern in Africa, causing ~49,600 deaths every year. The most common Salmonella enterica pathovariant associated with invasive nontyphoidal Salmonella disease is Salmonella Typhimurium sequence type (ST)313. It has been proposed that antimicrobial resistance and genome degradation has contributed to the success of ST313 lineages in Africa, but the evolutionary trajectory of such changes was unclear. Here, to define the evolutionary dynamics of ST313, we sub-sampled from two comprehensive collections of Salmonella isolates from African patients with bloodstream infections, spanning 1966 to 2018. The resulting 680 genome sequences led to the discovery of a pan-susceptible ST313 lineage (ST313 L3), which emerged in Malawi in 2016 and is closely related to ST313 variants that cause gastrointestinal disease in the United Kingdom and Brazil. Genomic analysis revealed degradation events in important virulence genes in ST313 L3, which had not occurred in other ST313 lineages. Despite arising only recently in the clinic, ST313 L3 is a phylogenetic intermediate between ST313 L1 and L2, with a characteristic accessory genome. Our in-depth genotypic and phenotypic characterization identifies the crucial loss-of-function genetic events that occurred during the stepwise evolution of invasive S. Typhimurium across Africa.


Assuntos
Evolução Molecular , Infecções por Salmonella/microbiologia , Salmonella typhimurium/genética , Sepse/microbiologia , África/epidemiologia , Farmacorresistência Bacteriana , Variação Genética , Genoma Bacteriano/genética , Genótipo , Humanos , Fenótipo , Filogenia , Plasmídeos/genética , Pseudogenes , Infecções por Salmonella/epidemiologia , Salmonella typhimurium/isolamento & purificação , Salmonella typhimurium/patogenicidade , Salmonella typhimurium/fisiologia , Sepse/epidemiologia , Sepse/transmissão , Virulência
9.
Cancer Res ; 80(15): 3062-3069, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32245795

RESUMO

Next-generation sequencing has sparked the exploration of cancer genomes, with the aim of discovering the genetic etiology of the disease and proposing rationally designed therapeutic interventions. Driver gene alterations have been comprehensively charted, but the improvement of cancer patient management somewhat lags behind these basic breakthroughs. Recently, large-scale sequencing that focused on metastasis, the main cause of cancer-related deaths, has shed new light on the driving forces at work during disease progression, particularly in breast cancer. Despite a fairly stable pool of driver genetic alterations between early and late disease, a number of therapeutically targetable mutations have been found enriched in metastatic samples. The molecular processes fueling disease progression have been delineated in recent studies and the clonal composition of breast cancer samples can be examined in detail. Here we discuss how these findings may be combined to improve the diagnosis of breast cancer to better select patients at risk, and to identify targeted agents to treat advanced diseases and to design therapeutic strategies exploiting vulnerabilities of cancer cells rooted in their ability to evolve and drive disease progression.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/terapia , Evolução Clonal/genética , Terapia de Alvo Molecular , Mutação , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/patologia , Evolução Clonal/efeitos dos fármacos , Análise Mutacional de DNA , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Terapia de Alvo Molecular/efeitos adversos , Terapia de Alvo Molecular/métodos , Metástase Neoplásica , Prognóstico
10.
Breast Cancer Res Treat ; 179(2): 387-401, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31620934

RESUMO

PURPOSE: Hormone receptor-positive (HR+) and human epidermal growth factor receptor 2 negative (HER2-) early breast cancer (BC) is the most prevalent BC subtype with substantial biological heterogeneity. Although clinicopathological (CP) characteristics have a clear prognostic value, additional biomarkers could refine survival prediction and guide treatment decision. METHODS: Copy number aberrations and somatic driver mutations were obtained with OncoScan CGH array and sequencing of 36 genes on HR+/HER2- node-positive early BC patients treated with chemotherapy from the PACS04 trial. We built a two-gene genomic score (GS) associated with distant disease-free survival (DDFS), whose prognostic value was assessed on the external METABRIC data (n = 1413) using overall survival (OS) and breast cancer-specific survival (BCSS). RESULTS: In the PACS04 trial (n = 327), the median follow-up for DDFS (65 events) was 9.6 years. FGFR1 amplifications ([Formula: see text] = 2.44, 95% CI [1.25; 4.76], p = 0.009) and MAP3K1 mutations ([Formula: see text] = 0.10, [0.01; 0.78], p = 0.03) were associated with DDFS beyond CP characteristics. A prognostic GS combining FGFR1 amplifications and MAP3K1 mutations added more information to CP model ([Formula: see text] = 12.97, [Formula: see text] < 0.001 and [Formula: see text] = 11.52, [Formula: see text] < 0.001). In the METABRIC study (n = 1413), FGFR1 amplifications ([Formula: see text] = 2.00 [1.40; 2.87], p < 0.001) and MAP3K1 mutations ([Formula: see text] = 0.58 [0.41; 0.83], p = 0.003) were significantly associated with BCSS beyond CP characteristics. The prognostic GS added significant prognostic information to CP model ([Formula: see text] = 15.39, [Formula: see text] < 0.001 and [Formula: see text] = 5.62, [Formula: see text] = 0.02). CONCLUSION: In axillary node-positive, HR+, and HER2- early BC, amplifications of FGFR1 gene were strongly associated with increased risk for distant disease, while mutations of MAP3K1 gene were significantly associated with decreased risk.


Assuntos
Biomarcadores Tumorais , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Variações do Número de Cópias de DNA , MAP Quinase Quinase Quinase 1/genética , Mutação , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/genética , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Axila/patologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Ensaios Clínicos Fase III como Assunto , Feminino , Humanos , Linfonodos/patologia , Metástase Linfática , MAP Quinase Quinase Quinase 1/metabolismo , Estadiamento de Neoplasias , Prognóstico , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Resultado do Tratamento
11.
Curr Biol ; 28(15): 2420-2428.e10, 2018 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-30033331

RESUMO

Salmonella enterica serovar Paratyphi C causes enteric (paratyphoid) fever in humans. Its presentation can range from asymptomatic infections of the blood stream to gastrointestinal or urinary tract infection or even a fatal septicemia [1]. Paratyphi C is very rare in Europe and North America except for occasional travelers from South and East Asia or Africa, where the disease is more common [2, 3]. However, early 20th-century observations in Eastern Europe [3, 4] suggest that Paratyphi C enteric fever may once have had a wide-ranging impact on human societies. Here, we describe a draft Paratyphi C genome (Ragna) recovered from the 800-year-old skeleton (SK152) of a young woman in Trondheim, Norway. Paratyphi C sequences were recovered from her teeth and bones, suggesting that she died of enteric fever and demonstrating that these bacteria have long caused invasive salmonellosis in Europeans. Comparative analyses against modern Salmonella genome sequences revealed that Paratyphi C is a clade within the Para C lineage, which also includes serovars Choleraesuis, Typhisuis, and Lomita. Although Paratyphi C only infects humans, Choleraesuis causes septicemia in pigs and boar [5] (and occasionally humans), and Typhisuis causes epidemic swine salmonellosis (chronic paratyphoid) in domestic pigs [2, 3]. These different host specificities likely evolved in Europe over the last ∼4,000 years since the time of their most recent common ancestor (tMRCA) and are possibly associated with the differential acquisitions of two genomic islands, SPI-6 and SPI-7. The tMRCAs of these bacterial clades coincide with the timing of pig domestication in Europe [6].


Assuntos
DNA Antigo/análise , DNA Bacteriano/análise , Instabilidade Genômica , Salmonella enterica/genética , Febre Tifoide/microbiologia , Feminino , Ilhas Genômicas , Humanos , Noruega
12.
Lancet Infect Dis ; 18(2): 207-214, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29198740

RESUMO

BACKGROUND: Ampicillin, the first semi-synthetic penicillin active against Enterobacteriaceae, was released onto the market in 1961. The first outbreaks of disease caused by ampicillin-resistant strains of Salmonella enterica serotype Typhimurium were identified in the UK in 1962 and 1964. We aimed to date the emergence of this resistance in historical isolates of S enterica serotype Typhimurium. METHODS: In this retrospective, whole-genome sequencing study, we analysed 288 S enterica serotype Typhimurium isolates collected between 1911 and 1969 from 31 countries on four continents and from various sources including human beings, animals, feed, and food. All isolates were tested for antimicrobial drug susceptibility with the disc diffusion method, and isolates shown to be resistant to ampicillin underwent resistance-transfer experiments. To provide insights into population structure and mechanisms of ampicillin resistance, we did whole-genome sequencing on a subset of 225 isolates, selected to maximise source, spatiotemporal, and genetic diversity. FINDINGS: 11 (4%) of 288 isolates were resistant to ampicillin because of acquisition of various ß lactamase genes, including blaTEM-1, carried by various plasmids, including the virulence plasmid of S enterica serotype Typhimurium. These 11 isolates were from three phylogenomic groups. One isolate producing TEM-1 ß lactamase was isolated in France in 1959 and two isolates producing TEM-1 ß lactamase were isolated in Tunisia in 1960, before ampicillin went on sale. The vectors for ampicillin resistance were different from those reported in the strains responsible for the outbreaks in the UK in the 1960s. INTERPRETATION: The association between antibiotic use and selection of resistance determinants is not as direct as often presumed. Our results suggest that the non-clinical use of narrow-spectrum penicillins (eg, benzylpenicillin) might have favoured the diffusion of plasmids carrying the blaTEM-1 gene in S enterica serotype Typhimurium in the late 1950s. FUNDING: Institut Pasteur, Santé publique France, the French Government's Investissement d'Avenir programme, the Fondation Le Roch-Les Mousquetaires.


Assuntos
Resistência a Ampicilina , Microbiologia de Alimentos , Transferência Genética Horizontal , Plasmídeos , Salmonelose Animal/microbiologia , Infecções por Salmonella/microbiologia , Salmonella typhimurium/efeitos dos fármacos , Ampicilina/uso terapêutico , Animais , Antibacterianos/uso terapêutico , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , França , Técnicas de Transferência de Genes , Saúde Global , História do Século XX , Humanos , Estudos Retrospectivos , Infecções por Salmonella/história , Salmonelose Animal/história , Salmonella typhimurium/classificação , Salmonella typhimurium/genética , Salmonella typhimurium/isolamento & purificação , Tunísia , Reino Unido , Sequenciamento Completo do Genoma
14.
Nat Microbiol ; 1: 16027, 2016 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-27572446

RESUMO

Together with plague, smallpox and typhus, epidemics of dysentery have been a major scourge of human populations for centuries(1). A previous genomic study concluded that Shigella dysenteriae type 1 (Sd1), the epidemic dysentery bacillus, emerged and spread worldwide after the First World War, with no clear pattern of transmission(2). This is not consistent with the massive cyclic dysentery epidemics reported in Europe during the eighteenth and nineteenth centuries(1,3,4) and the first isolation of Sd1 in Japan in 1897(5). Here, we report a whole-genome analysis of 331 Sd1 isolates from around the world, collected between 1915 and 2011, providing us with unprecedented insight into the historical spread of this pathogen. We show here that Sd1 has existed since at least the eighteenth century and that it swept the globe at the end of the nineteenth century, diversifying into distinct lineages associated with the First World War, Second World War and various conflicts or natural disasters across Africa, Asia and Central America. We also provide a unique historical perspective on the evolution of antibiotic resistance over a 100-year period, beginning decades before the antibiotic era, and identify a prevalent multiple antibiotic-resistant lineage in South Asia that was transmitted in several waves to Africa, where it caused severe outbreaks of disease.


Assuntos
Disenteria Bacilar/epidemiologia , Disenteria Bacilar/microbiologia , Evolução Molecular , Filogeografia , Sorogrupo , Shigella dysenteriae/classificação , Shigella dysenteriae/isolamento & purificação , Farmacorresistência Bacteriana , Disenteria Bacilar/história , Genoma Bacteriano , Saúde Global , História do Século XIX , História do Século XX , História do Século XXI , Humanos , Epidemiologia Molecular , Análise de Sequência de DNA , Shigella dysenteriae/genética
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