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2.
Int J Tuberc Lung Dis ; 27(6): 471-477, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37231607

RESUMO

BACKGROUND: New tools for diagnosis and treatment of rifampicin-resistant (RR-) and multidrug-resistant (MDR-) TB have become available in the last decade, including better tests confirming transmission.OBJECTIVE: To analyse transmission risks of MDR/RR-TB in the Netherlands.METHODS: Analysis of national data of patients with MDR/RR-TB notified in 2010-2019, including contact investigation and genotyping data.RESULTS: Patients with MDR/RR-TB (n = 121) were more often female (adjusted odds ratio [aOR] 1.5), foreign-born, previously treated for TB (aOR 5.2) and co-infected with HIV (aOR 2.3) than patients with no MDR/RR-TB. Treatment outcomes were satisfactory, with at least 79% completing treatment. After additional whole-genome sequencing (WGS), five molecular clusters of 16 patients remained. Patients in three clusters could not be epidemiologically linked and were unlikely to have been infected in the Netherlands. The remaining eight (6.6%) patients with MDR/RR-TB belonged to two clusters, and were likely the result of transmission in the Netherlands. Among close contacts of patients with smear-positive pulmonary MDR/RR-TB, 13.4% (n = 38) had TB infection and 1.1% (n = 3) had TB disease. Only six contacts with TB infection were treated with a quinolone-based preventive treatment regimen.CONCLUSION: MDR/RR-TB is effectively controlled in the Netherlands. Preventive treatment options could be considered more frequently in contacts clearly infected by an index patient with MDR-TB.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Tuberculose Pulmonar , Humanos , Feminino , Rifampina/uso terapêutico , Rifampina/farmacologia , Antituberculosos/farmacologia , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Países Baixos/epidemiologia , Tuberculose Pulmonar/diagnóstico , Mycobacterium tuberculosis/genética
5.
Cancer Res ; 83(11): 1917-1927, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-36971477

RESUMO

Large B-cell lymphoma of immune-privileged sites (LBCL-IP) arise in immune sanctuaries including the testis and central nervous system (CNS). After initially reaching complete response, relapses occur in almost 50% of patients, typically at other immune-privileged sites. Resolution of the clonal relationships and evolutionary patterns of LBCL-IP is required to understand the unique clinical behavior. We collected a unique set of 33 primary-relapse LBCL-IP sample pairs and performed next-generation sequencing for copy number, mutation, translocation, and immunoglobulin clonality analysis. All LBCL-IP sample pairs were clonally related, and both tumors developed from a common progenitor cell (CPC) with MYD88 and TBL1XR1 mutations and/or BCL6 translocations in 30/33 cases, indicating that these are early genetic events. This was succeeded by intermediate genetic events including shared, as well as unique alterations in targets of aberrant somatic hypermutation (aSHM), CD79B mutations, and 9p21.3/CDKN2A loss. Genetic alterations in genes involved in immune escape (HLA, CD274/PDCD1LG2) were predominantly unique in primary and relapse samples and thus considered late genetic events. Together, this study indicates that primary and relapsed LBCL-IP follow an early parallel evolutionary pattern where the CPC contains genetic alterations that support prolonged survival/proliferation and retention in a memory B-cell state, followed by germinal center reentry, aSHM and immune escape. SIGNIFICANCE: Genomic analyses reveal that primary and relapse LBCL-IP originate from a common progenitor cell with a small set of genetic alterations, followed by extensive parallel diversification, elucidating the clonal evolution of LBCL-IP.


Assuntos
Linfoma Difuso de Grandes Células B , Células Precursoras de Linfócitos B , Masculino , Humanos , Células Precursoras de Linfócitos B/patologia , Recidiva Local de Neoplasia/genética , Linfoma Difuso de Grandes Células B/genética , Mutação , Evolução Clonal/genética
6.
Front Oncol ; 12: 970063, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36387143

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is a widely heterogeneous disease in presentation, treatment response and outcome that results from a broad biological heterogeneity. Various stratification approaches have been proposed over time but failed to sufficiently capture the heterogeneous biology and behavior of the disease in a clinically relevant manner. The most recent DNA-based genomic subtyping studies are a major step forward by offering a level of refinement that could serve as a basis for exploration of personalized and targeted treatment for the years to come. To enable consistent trial designs and allow meaningful comparisons between studies, harmonization of the currently available knowledge into a single genomic classification widely applicable in daily practice is pivotal. In this review, we investigate potential avenues for harmonization of the presently available genomic subtypes of DLBCL inspired by consensus molecular classifications achieved for other malignancies. Finally, suggestions for laboratory techniques and infrastructure required for successful clinical implementation are described.

7.
Int J Tuberc Lung Dis ; 26(11): 1050-1057, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36281056

RESUMO

BACKGROUND: One of the challenges of TB elimination in low-incidence countries is the relatively high incidence of TB in migrants in these countries, even after multiple years of residence.OBJECTIVE: To describe and compare TB incidence and characteristics of migrant TB patients residing in the Netherlands for at least (≥)5 years at diagnosis with non-foreign-born TB patients in order to identify additional strategies that could reduce TB incidence in the former group.METHODS: A retrospective cohort study was conducted in migrants from Somalia, Morocco, Suriname, Turkey and Indonesia who were diagnosed with TB in the Netherlands in 2003-2018. TB incidences were calculated and multivariate logistic regression was used to identify differences in characteristics of TB patients per country of birth compared to non-foreign-born patients.RESULTS: TB incidence was highest in individuals from Somalia (162.5/100,000 population in 2018), followed by individuals from Morocco (37.1/100,000). In the non-foreign-born population, TB incidence was 1.2/100,000. Differences in characteristics of TB patients compared to non-foreign-born patients varied by country of birth.CONCLUSION: Our findings underline the importance of being aware of the heterogeneity of TB incidence and characteristics of patients in the migrant population residing ≥5 years in the Netherlands.


Assuntos
Migrantes , Tuberculose , Humanos , Incidência , Países Baixos/epidemiologia , Estudos Retrospectivos , Turquia , Tuberculose/epidemiologia
8.
Int J Tuberc Lung Dis ; 26(10): 942-948, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36163670

RESUMO

INTRODUCTION The WHO End TB Strategy emphasises early diagnosis and screening of TB in high-risk groups, including migrants. We analysed TB yield data from four large migrant TB screening programmes to inform TB policy.METHODS We pooled routinely collected individual TB screening episode data from Italy, the Netherlands, Sweden and the United Kingdom under the European Union Commission E-DETECT.TB grant, described characteristics of the screened population, and analysed TB case yield.RESULTS We collected data on 2,302,260 screening episodes among 2,107,016 migrants, mostly young adults aged 18-44 years (77.8%) from Asia (78%) and Africa (18%). There were 1,658 TB cases detected through screening, with substantial yield variation (per 100,000): 201.1 for Sweden (95% confidence intervals CI 111.4-362.7), 68.9 (95% CI 65.4-72.7) for the United Kingdom, 83.2 (95% CI 73.3-94.4) for the Netherlands and 653.6 (95% CI 445.4-958.2) in Italy. Most TB cases were notified among migrants from Asia (n = 1,206, 75/100,000) or Africa (n = 370, 76.4/100,000), and among asylum seekers (n = 174, 131.5/100,000), migrants to the Netherlands (n = 101, 61.9/100,000) and settlement visa migrants to the United Kingdom (n = 590, 120.3/100,000).CONCLUSIONS We found considerable variations in yield across programmes, types of migrants and country of origin. These variations may be partly explained by differences in migration patterns and programmatic characteristics.


Assuntos
Refugiados , Migrantes , Tuberculose , Europa (Continente)/epidemiologia , Humanos , Programas de Rastreamento/métodos , Tuberculose/epidemiologia , Adulto Jovem
9.
Blood Adv ; 6(18): 5482-5493, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-35816682

RESUMO

Although the genomic and immune microenvironmental landscape of follicular lymphoma (FL) has been extensively investigated, little is known about the potential biological differences between stage I and stage III/IV disease. Using next-generation sequencing and immunohistochemistry, 82 FL nodal stage I cases were analyzed and compared with 139 FL stage III/IV nodal cases. Many similarities in mutations, chromosomal copy number aberrations, and microenvironmental cell populations were detected. However, there were also significant differences in microenvironmental and genomic features. CD8+ T cells (P = .02) and STAT6 mutations (false discovery rate [FDR] <0.001) were more frequent in stage I FL. In contrast, programmed cell death protein 1-positive T cells, CD68+/CD163+ macrophages (P < .001), BCL2 translocation (BCL2trl+) (P < .0001), and KMT2D (FDR = 0.003) and CREBBP (FDR = 0.04) mutations were found more frequently in stage III/IV FL. Using clustering, we identified 3 clusters within stage I, and 2 clusters within stage III/IV. The BLC2trl+ stage I cluster was comparable to the BCL2trl+ cluster in stage III/IV. The two BCL2trl- stage I clusters were unique for stage I. One was enriched for CREBBP (95%) and STAT6 (64%) mutations, without BLC6 translocation (BCL6trl), whereas the BCL2trl- stage III/IV cluster contained BCL6trl (64%) with fewer CREBBP (45%) and STAT6 (9%) mutations. The other BCL2trl- stage I cluster was relatively heterogeneous with more copy number aberrations and linker histone mutations. This exploratory study shows that stage I FL is genetically heterogeneous with different underlying oncogenic pathways. Stage I FL BCL2trl- is likely STAT6 driven, whereas BCL2trl- stage III/IV appears to be more BCL6trl driven.


Assuntos
Linfoma Folicular , Genômica , Histonas/genética , Humanos , Linfoma Folicular/genética , Receptor de Morte Celular Programada 1/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Translocação Genética
10.
Sleep Breath ; 26(3): 1399-1407, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34561757

RESUMO

PURPOSE: Data from large patient registry studies suggested an increased incidence and increased mortality in coronavirus disease-2019 (COVID-19) in patients with a history of obstructive sleep apnea (OSA). This study aimed to compare the prevalence of OSA in patients with and without COVID-19 among patients admitted to the same hospital in the same time period. In addition, the impact of OSA on clinical outcomes of COVID-19 infection was investigated. METHODS: Observational cohort study. Clinical data were collected retrospectively from the complete medical records for each patient individually from March 1st 2020 to May 16th 2020. RESULTS: A total of 723 patients were diagnosed with COVID-19 and 1161 with non-COVID-19 disease. The prevalence of OSA did not differ between these groups (n = 49; 6.8% versus n = 66; 5.7%; p = 0.230). In patients with COVID-19, mortality was increased in the group of 49 patients with OSA (n = 17; 34.7%) compared to 674 COVID-19 patients without OSA (n = 143; 21.2%; p = 0.028). This increased risk of mortality in COVID-19 patients with OSA (OR = 2.590; 95%CI 1.218-5.507) was independent from Body Mass Index (BMI), male gender, age, diabetes, cardiovascular disease, and obstructive lung disease. Presence of OSA in COVID-19 disease was further associated with an increased length of hospital stay (12.6 ± 15.7 days versus 9.6 ± 9.9 days; p = 0.049). CONCLUSION: The prevalence of OSA did not differ between patients with or without COVID-19, but mortality and hospital length of stay were increased in patients with OSA and comorbid COVID-19. Hence, OSA should be included in COVID-19 risk factor analyses, Clinicians should be aware of the association and the mechanism should be further explored.


Assuntos
COVID-19 , Apneia Obstrutiva do Sono , Hospitalização , Humanos , Tempo de Internação , Masculino , Estudos Retrospectivos , Fatores de Risco
11.
Nat Commun ; 12(1): 3361, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099699

RESUMO

In routine diagnostic pathology, cancer biopsies are preserved by formalin-fixed, paraffin-embedding (FFPE) procedures for examination of (intra-) cellular morphology. Such procedures inadvertently induce DNA fragmentation, which compromises sequencing-based analyses of chromosomal rearrangements. Yet, rearrangements drive many types of hematolymphoid malignancies and solid tumors, and their manifestation is instructive for diagnosis, prognosis, and treatment. Here, we present FFPE-targeted locus capture (FFPE-TLC) for targeted sequencing of proximity-ligation products formed in FFPE tissue blocks, and PLIER, a computational framework that allows automated identification and characterization of rearrangements involving selected, clinically relevant, loci. FFPE-TLC, blindly applied to 149 lymphoma and control FFPE samples, identifies the known and previously uncharacterized rearrangement partners. It outperforms fluorescence in situ hybridization (FISH) in sensitivity and specificity, and shows clear advantages over standard capture-NGS methods, finding rearrangements involving repetitive sequences which they typically miss. FFPE-TLC is therefore a powerful clinical diagnostics tool for accurate targeted rearrangement detection in FFPE specimens.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/métodos , Linfoma de Células B/genética , Linfoma não Hodgkin/genética , Inclusão em Parafina/métodos , Fixação de Tecidos/métodos , Translocação Genética , Biologia Computacional/métodos , Rearranjo Gênico , Genes bcl-2/genética , Genes myc/genética , Humanos , Hibridização in Situ Fluorescente/métodos , Linfoma de Células B/diagnóstico , Linfoma não Hodgkin/diagnóstico , Proteínas Proto-Oncogênicas c-bcl-6/genética , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
14.
J Clin Tuberc Other Mycobact Dis ; 23: 100222, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33598570

RESUMO

BACKGROUND: Rifampicin resistant tuberculosis (RR-TB) was frequently detected in Suriname after the introduction of Xpert MTB/RIF in 2012. Subsequent phenotypic drug-susceptibility testing (DST) was not conclusive at that moment, while RR-TB patients treated with first-line tuberculostatics had good treatment outcome. In our study, we analysed this interesting observation. METHODS: We collected demographic and clinical characteristics and treatment outcome of TB patients from May 2012-December 2018 and performed a univariate and multivariate analysis to assess possible associations with resistance to rifampicin. Secondly, we conducted whole genome sequencing on all available Mycobacterium tuberculosis isolates that had a rifampicin resistance in the Xpert MTB/RIF test and performed phenotypic DST on selected isolates. FINDINGS: RR-TB was detected in 59 (9.6%) patients confirmed by Xpert. These patients were treated with rifampicin-containing regimens in most (88%) of the cases. In all 32 samples examined, a D435Y mutation in the rpoB gene was identified; only one isolate revealed an additional isoniazid mutation. Phenotypic DST indicated low-level rifampicin resistance. In multivariate analysis, the Creole ethnicity was a factor associated with rifampicin resistance (aOR 3.5; 95%CI 1.9-6.4). The treatment success rate for patients with RR-TB (78.0%) was comparable to the treatment outcome in non-RR-TB patients 77.8%. INTERPRETATION: This study confirms a low-level rifampicin mono-resistance in TB patients of Suriname. These patients could benefit from a first-line regimen with high dose rifampicin (or rifabutin), rather than from the lengthy treatment regimens for rifampicin-resistant and multi-drug resistant TB, a concept of stratified medicine also advocated for the treatment of TB. FUNDING: None.

15.
Blood ; 136(25): 2927-2932, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33331925

RESUMO

Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a very rare type of T-cell lymphoma that is uniquely caused by a single environmental stimulus. Here, we present a comprehensive genetic analysis of a relatively large series of BIA-ALCL (n = 29), for which genome-wide chromosomal copy number aberrations (CNAs) and mutational profiles for a subset (n = 7) were determined. For comparison, CNAs for anaplastic lymphoma kinase (ALK)- nodal anaplastic large cell lymphomas (ALCLs; n = 24) were obtained. CNAs were detected in 94% of BIA-ALCLs, with losses at chromosome 20q13.13 in 66% of the samples. Loss of 20q13.13 is characteristic of BIA-ALCL compared with other classes of ALCL, such as primary cutaneous ALCL and systemic type ALK+ and ALK- ALCL. Mutational patterns confirm that the interleukin-6-JAK1-STAT3 pathway is deregulated. Although this is commonly observed across various types of T-cell lymphomas, the extent of deregulation is significantly higher in BIA-ALCL, as indicated by phosphorylated STAT3 immunohistochemistry. The characteristic loss of chromosome 20 in BIA-ALCL provides further justification to recognize BIA-ALCL as a separate disease entity. Moreover, CNA analysis may serve as a parameter for future diagnostic assays for women with breast implants to distinguish seroma caused by BIA-ALCL from other causes of seroma accumulation, such as infection or trauma.


Assuntos
Implantes de Mama/efeitos adversos , Neoplasias da Mama , Deleção Cromossômica , Cromossomos Humanos Par 20 , Linfoma Anaplásico de Células Grandes , Mutação , Proteínas de Neoplasias , Neoplasias da Mama/etiologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Cromossomos Humanos Par 20/genética , Cromossomos Humanos Par 20/metabolismo , Feminino , Humanos , Linfoma Anaplásico de Células Grandes/etiologia , Linfoma Anaplásico de Células Grandes/genética , Linfoma Anaplásico de Células Grandes/metabolismo , Linfoma Anaplásico de Células Grandes/patologia , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Estudos Retrospectivos
16.
Radiography (Lond) ; 26 Suppl 2: S94-S99, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32291123

RESUMO

INTRODUCTION: With the introduction of digital radiography, the feedback between image quality and over-exposure has been partly lost which in some cases has led to a steady increase in dose. Over the years the introduction of exposure index (EI) has been used to resolve this phenomenon referred to as 'dose creep'. Even though EI is often vendor specific it is always a related of the radiation exposure to the detector. Due to the nature of this relationship EI can also be used as a patient dose indicator, however this is not widely investigated in literature. METHODS: A total of 420 dose-area-product (DAP) and EI measurements were taken whilst varying kVp, mAs and body habitus on two different anthropomorphic phantoms (pelvis and chest). Using linear regression, the correlation between EI and DAP were examined. Additionally, two separate region of interest (ROI) placements/per phantom where examined in order to research any effect on EI. RESULTS: When dividing the data into subsets, a strong correlation between EI and DAP was shown with all R-squared values > 0.987. Comparison between the ROI placements showed a significant difference between EIs for both placements. CONCLUSION: This research shows a clear relationship between EI and radiation dose which is dependent on a wide variety of factors such as ROI placement, body habitus. In addition, pathology and manufacturer specific EI's are likely to be of influence as well. IMPLICATIONS FOR PRACTICE: The combination of DAP and EI might be used as a patient dose indicator. However, the influencing factors as mentioned in the conclusion should be considered and examined before implementation.


Assuntos
Doses de Radiação , Exposição à Radiação , Intensificação de Imagem Radiográfica , Humanos , Imagens de Fantasmas , Reprodutibilidade dos Testes
17.
Radiography (Lond) ; 26(3): e134-e139, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32052753

RESUMO

INTRODUCTION: In the Netherlands, Diagnostic Reference Levels (DRLs) have not been based on a national survey as proposed by ICRP. Instead, local exposure data, expert judgment and the international scientific literature were used as sources. This study investigated whether the current DRLs are reasonable for Dutch radiological practice. METHODS: A national project was set up, in which radiography students carried out dose measurements in hospitals supervised by medical physicists. The project ran from 2014 to 2017 and dose values were analysed for a trend over time. In the absence of such a trend, the joint yearly data sets were considered a single data set and were analysed together. In this way the national project mimicked a national survey. RESULTS: For six out of eleven radiological procedures enough data was collected for further analysis. In the first step of the analysis no trend was found over time for any of these procedures. In the second step the joint analysis lead to suggestions for five new DRL values that are far below the current ones. The new DRLs are based on the 75 percentile values of the distributions of all dose data per procedure. CONCLUSION: The results show that the current DRLs are too high for five of the six procedures that have been analysed. For the other five procedures more data needs to be collected. Moreover, the mean weights of the patients are higher than expected. This introduces bias when these are not recorded and the mean weight is assumed to be 77 kg. IMPLICATIONS FOR PRACTICE: The current checking of doses for compliance with the DRLs needs to be changed. Both the procedure (regarding weights) and the values of the DRLs should be updated.


Assuntos
Doses de Radiação , Exposição à Radiação/estatística & dados numéricos , Radiografia/estatística & dados numéricos , Níveis de Referência de Diagnóstico , Hospitais , Humanos , Países Baixos
19.
Br J Anaesth ; 121(1): 58-65, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29935595

RESUMO

BACKGROUND: Clinical risk factors for postoperative nausea and vomiting (PONV) are evaluated with the Apfel score, however patients with low Apfel scores still experience PONV suggesting a genetic predisposition. PONV risk associates with specific M3 muscarinic acetylcholine receptor (CHRM3) rs 2165870 polymorphism. We investigated whether the Apfel score and this genetic variation independently contribute to PONV risk and whether prophylaxis reduces PONV in patients with low Apfel score but at high genetic risk. METHODS: In a prospective, controlled study, 454 subjects undergoing elective surgery were genotyped for rs2165870 and its association with PONV was investigated with log-binomial regression analysis. Subjects were randomised to receive acustimulation/dexamethasone, acustimulation/vehicle, sham acustimulation/dexamethasone, or sham acustimulation/vehicle to investigate their effects on PONV risk. RESULTS: Early PONV occurred in 37% of subjects. The rs2165870 genotype distribution was GG in 191, GA in 207, and AA in 56 subjects. The CHRM3 polymorphism was associated with a relative risk (RR) of 1.5 for GA vs GG [95% confidence interval (CI): 1.1-1.9; P=0.003] and 1.6 for AA vs GG (95% CI: 1.1-2.2; P=0.009) genotypes to develop PONV, and this was independent from the Apfel score (RR per Apfel point: 1.3, 95% CI: 1.2-1.5; P<0.0001). While dexamethasone and acustimulation each reduced the PONV risk by 30% in AA genotype carriers with low Apfel score, combined therapy reduced the risk by 86% (P=0.015). CONCLUSIONS: The CHRM3 polymorphism and the Apfel score independently predict PONV susceptibility. Dexamethasone/acustimulation should be considered in patients with low Apfel score but at high genetic risk. CLINICAL TRIAL REGISTRATION: DRKS00005664.


Assuntos
Polimorfismo Genético/genética , Náusea e Vômito Pós-Operatórios/epidemiologia , Náusea e Vômito Pós-Operatórios/genética , Receptor Muscarínico M3/genética , Terapia por Acupuntura , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral , Antieméticos , Terapia Combinada , Dexametasona , Procedimentos Cirúrgicos Eletivos , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Náusea e Vômito Pós-Operatórios/prevenção & controle , Valor Preditivo dos Testes , Estudos Prospectivos , Risco , Adulto Jovem
20.
Cell ; 173(6): 1413-1425.e14, 2018 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-29754815

RESUMO

BRAF(V600E) mutant melanomas treated with inhibitors of the BRAF and MEK kinases almost invariably develop resistance that is frequently caused by reactivation of the mitogen activated protein kinase (MAPK) pathway. To identify novel treatment options for such patients, we searched for acquired vulnerabilities of MAPK inhibitor-resistant melanomas. We find that resistance to BRAF+MEK inhibitors is associated with increased levels of reactive oxygen species (ROS). Subsequent treatment with the histone deacetylase inhibitor vorinostat suppresses SLC7A11, leading to a lethal increase in the already-elevated levels of ROS in drug-resistant cells. This causes selective apoptotic death of only the drug-resistant tumor cells. Consistently, treatment of BRAF inhibitor-resistant melanoma with vorinostat in mice results in dramatic tumor regression. In a study in patients with advanced BRAF+MEK inhibitor-resistant melanoma, we find that vorinostat can selectively ablate drug-resistant tumor cells, providing clinical proof of concept for the novel therapy identified here.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Sistema y+ de Transporte de Aminoácidos/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Humanos , MAP Quinase Quinase 1/metabolismo , Sistema de Sinalização das MAP Quinases , Melanoma/genética , Camundongos , Mutação , Transplante de Neoplasias , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Cutâneas/genética , Resultado do Tratamento , Vorinostat/farmacologia
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