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2.
Tumour Virus Res ; 14: 200247, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36100161

RESUMO

Persistent infection with Human Papillomavirus (HPV) is responsible for almost all cases of cervical cancers, and HPV16 and HPV18 associated with the majority of these. These types differ in the proportion of viral minor nucleotide variants (MNVs) caused by APOBEC3 mutagenesis as well as integration frequencies. Whether these traits extend to other types remains uncertain. This study aimed to investigate and compare genomic variability and chromosomal integration in the two phylogenetically distinct Alpha-7 and Alpha-9 clades of carcinogenic HPV types. The TaME-seq protocol was employed to sequence cervical cell samples positive for HPV31, HPV33 or HPV45 and combine these with data from a previous study on HPV16 and HPV18. APOBEC3 mutation signatures were found in Alpha-9 (HPV16/31/33) but not in Alpha-7 (HPV18/45). HPV45 had significantly more MNVs compared to the other types. Alpha-7 had higher integration frequency compared to Alpha-9. An increase in integration frequency with increased diagnostic severity was found for Alpha-7. The results highlight important differences and broaden our understanding of the molecular mechanisms behind cervical cancer induced by high-risk HPV types from the Alpha-7 and Alpha-9 clades.


Assuntos
Infecções por Papillomavirus , Neoplasias do Colo do Útero , Feminino , Humanos , Infecções por Papillomavirus/genética , Filogenia , Papillomavirus Humano 18/genética , Papillomavirus Humano 16/genética , Papillomaviridae/genética , Neoplasias do Colo do Útero/genética , Desaminases APOBEC/genética
3.
Tumour Virus Res ; 12: 200221, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34175494

RESUMO

Human papillomavirus (HPV) 16 and 18 are the most predominant types in cervical cancer. Only a small fraction of HPV infections progress to cancer, indicating that additional factors and genomic events contribute to the carcinogenesis, such as minor nucleotide variation caused by APOBEC3 and chromosomal integration. We analysed intra-host minor nucleotide variants (MNVs) and integration in HPV16 and HPV18 positive cervical samples with different morphology. Samples were sequenced using an HPV whole genome sequencing protocol TaME-seq. A total of 80 HPV16 and 51 HPV18 positive samples passed the sequencing depth criteria of 300× reads, showing the following distribution: non-progressive disease (HPV16 n = 21, HPV18 n = 12); cervical intraepithelial neoplasia (CIN) grade 2 (HPV16 n = 27, HPV18 n = 9); CIN3/adenocarcinoma in situ (AIS) (HPV16 n = 27, HPV18 n = 30); cervical cancer (HPV16 n = 5). Similar numbers of MNVs in HPV16 and HPV18 samples were observed for most viral genes, with the exception of HPV18 E4 with higher numbers across clinical categories. APOBEC3 signatures were observed in HPV16 lesions, while similar mutation patterns were not detected for HPV18. The proportion of samples with integration was 13% for HPV16 and 59% for HPV18 positive samples, with a noticeable portion located within or close to cancer-related genes.


Assuntos
Desaminases APOBEC/genética , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Colo do Útero , Feminino , Papillomavirus Humano 16 , Papillomavirus Humano 18 , Humanos , Infecções por Papillomavirus/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/virologia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/virologia
4.
PLoS One ; 16(4): e0250426, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33901223

RESUMO

BACKGROUND & AIM: Women with HIV/HPV coinfection and cervical lesions are at increased risk of developing HPV related anal cancer. Self-collection of anal swabs may facilitate HPV molecular testing in anal cancer screening, especially in high-risk groups, and yet it is not adequately studied. We evaluated level of agreement between self-collected anal swabs (SCAS) and clinician-collected anal swabs (CCAS) when used for HPV genotyping. We also described the anal HPV genotype distribution and HIV/HPV coinfection. METHODS: We performed a cross sectional study with participants from a visual-inspection-with-acetic-acid and cervicography (VIAC) clinic, in Harare, Zimbabwe. In a clinic setting, the women aged ≥18 years provided anal swabs in duplicate; first CCAS and then SCAS immediately after. HPV detection and genotyping were performed using next generation amplicon sequencing of a 450bp region of the HPV L1 gene. Level of agreement of HPV genotypes between CCAS and SCAS was calculated using the kappa statistic. McNemar tests were used to evaluate agreement in the proportion of genotypes detected by either method. RESULTS: Three-hundred women provided 600 samples for HPV genotyping. HPV genotypes were detected in 25% of SCAS and in 22% of CCAS. The most common genotypes with CCAS were HPV52, HPV62 and HPV70 and with SCAS were HPV62, HPV44, HPV52, HPV53 and HPV68. Total HPV genotypes detected in CCAS were more than those detected in SCAS, 32 versus 27. The agreement of HPV genotypes between the two methods was 0.55 in kappa value (k). The test of proportions using McNemar gave a Chi-square value of 0.75 (p = 0.39). Multiple HPV infections were detected in 28/75 and 29/67 women for CCAS and SCAS respectively. CONCLUSIONS: SCAS and CCAS anal swabs showed moderate agreement, with no statistically significant difference in the proportion of genotypes detected by either methods. Although the differences between the two methods were not statistically significant, CCAS detected more HPV genotypes than SCAS and more HPV infections were detected in SCAS than in CCAS. Our data suggest that self-collected anal swabs can be used as an alternative to clinician-collected anal swabs for HPV genotyping.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Neoplasias do Ânus/diagnóstico , Neoplasias do Ânus/epidemiologia , Coinfecção/epidemiologia , Detecção Precoce de Câncer/métodos , Genótipo , HIV , Programas de Rastreamento/métodos , Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Infecções por Papillomavirus/epidemiologia , Manejo de Espécimes/métodos , Infecções Oportunistas Relacionadas com a AIDS/virologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Canal Anal/virologia , Coinfecção/virologia , Estudos Transversais , DNA Viral/genética , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Adulto Jovem , Zimbábue/epidemiologia
5.
Cancers (Basel) ; 12(3)2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32188095

RESUMO

Peripheral T-cell lymphomas (PTCL) are a heterogeneous, and often aggressive group of non-Hodgkin lymphomas. Recent advances in the molecular and genetic characterization of PTCLs have helped to delineate differences and similarities between the various subtypes, and the JAK/STAT pathway has been found to play an important oncogenic role. Here, we aimed to characterize the JAK/STAT pathway in PTCL subtypes and investigate whether the activation of the pathway correlates with the frequency of STAT gene mutations. Patient samples from AITL (n = 30), ALCL (n = 21) and PTCL-NOS (n = 12) cases were sequenced for STAT3, STAT5B, JAK1, JAK3, and RHOA mutations using amplicon sequencing and stained immunohistochemically for pSTAT3, pMAPK, and pAKT. We discovered STAT3 mutations in 13% of AITL, 13% of ALK+ ALCL, 38% of ALK- ALCL and 17% of PTCL-NOS cases. However, no STAT5B mutations were found and JAK mutations were only present in ALK- ALCL (15%). Concurrent mutations were found in all subgroups except ALK+ ALCL where STAT3 mutations were always seen alone. High pY-STAT3 expression was observed especially in AITL and ALCL samples. When studying JAK-STAT pathway mutations, pY-STAT3 expression was highest in PTCLs harboring either JAK1 or STAT3 mutations and CD30+ phenotype representing primarily ALK- ALCLs. Further investigation is needed to elucidate the molecular mechanisms of JAK-STAT pathway activation in PTCL.

7.
Front Immunol ; 10: 2770, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31866997

RESUMO

Upon binding to pathogen or self-derived cytosolic nucleic acids cyclic GMP-AMP synthase (cGAS) triggers the production of cGAMP that further activates transmembrane protein STING. Upon activation STING translocates from ER via Golgi to vesicles. Monogenic STING gain-of-function mutations cause early-onset type I interferonopathy, with disease presentation ranging from fatal vasculopathy to mild chilblain lupus. Molecular mechanisms underlying the variable phenotype-genotype correlation are presently unclear. Here, we report a novel gain-of-function G207E STING mutation causing a distinct phenotype with alopecia, photosensitivity, thyroid dysfunction, and features of STING-associated vasculopathy with onset in infancy (SAVI), such as livedo reticularis, skin vasculitis, nasal septum perforation, facial erythema, and bacterial infections. Polymorphism in TMEM173 and IFIH1 showed variable penetrance in the affected family, implying contribution to varying phenotype spectrum. The G207E mutation constitutively activates inflammation-related pathways in vitro, and causes aberrant interferon signature and inflammasome activation in patient PBMCs. Treatment with Janus kinase 1 and 2 (JAK1/2) inhibitor baricitinib was beneficiary for a vasculitic ulcer, induced hair regrowth and improved overall well-being in one patient. Protein-protein interactions propose impaired cellular trafficking of G207E mutant. These findings reveal the molecular landscape of STING and propose common polymorphisms in TMEM173 and IFIH1 as likely modifiers of the phenotype.


Assuntos
Alelos , Estudos de Associação Genética , Predisposição Genética para Doença , Helicase IFIH1 Induzida por Interferon/genética , Proteínas de Membrana/genética , Mutação , Estudos de Casos e Controles , Consanguinidade , Feminino , Perfilação da Expressão Gênica , Ligação Genética , Humanos , Masculino , Linhagem , Transcriptoma , Sequenciamento Completo do Genoma
8.
J Clin Virol ; 119: 24-30, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31446251

RESUMO

BACKGROUND: Chronic infections by one of the oncogenic human papillomaviruses (HPVs) are responsible for near 5% of the global cancer burden and HPV16 is the type most often found in cancers. HPV genomes display unexpected levels of variation when deep-sequenced. Minor nucleotide variations (MNVs) may reveal HPV genomic instability and HPV-related carcinogenic transformation of host cells. OBJECTIVES: The objective of this study was to investigate HPV16 genome variation at the minor variant level on persisting HPV16 cervical infections from a population of young Dutch women. STUDY DESIGN: 15 HPV16 infections were sequenced using a whole-HPV genome deep sequencing protocol (TaME-seq). One infection was followed over a three-year period, eight were followed over a two-year period, three were followed over a one-year period and three infections had a single sampling point. RESULTS AND CONCLUSIONS: Using a 1% variant frequency cutoff, we find on average 48 MNVs per HPV16 genome and 1717 MNVs in total when sequencing coverage was >100 × . We find the transition mutation T > C to be the most common, in contrast to other studies detecting APOBEC-related C > T mutation profiles in pre-cancerous and cancer samples. Our results suggest that the relative mutagenic footprint of HPV16 genomes may differ between the infections in this study and transforming lesions. In addition, we identify a number of MNVs that have previously been associated with higher incidence of high-grade lesions (CIN3+) in a population study. These findings may provide a starting point for future studies exploring causality between emerging HPV minor genomic variants and cancer development.


Assuntos
Genoma Viral/genética , Papillomavirus Humano 16/genética , Infecções por Papillomavirus/virologia , Adolescente , Adulto , Colo do Útero/virologia , DNA Viral/genética , Feminino , Variação Genética , Papillomavirus Humano 16/isolamento & purificação , Humanos , Estudos Longitudinais , Mutação , Países Baixos/epidemiologia , Estudos Retrospectivos , Carga Viral , Adulto Jovem
9.
Sci Rep ; 9(1): 524, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30679491

RESUMO

HPV genomic variability and chromosomal integration are important in the HPV-induced carcinogenic process. To uncover these genomic events in an HPV infection, we have developed an innovative and cost-effective sequencing approach named TaME-seq (tagmentation-assisted multiplex PCR enrichment sequencing). TaME-seq combines tagmentation and multiplex PCR enrichment for simultaneous analysis of HPV variation and chromosomal integration, and it can also be adapted to other viruses. For method validation, cell lines (n = 4), plasmids (n = 3), and HPV16, 18, 31, 33 and 45 positive clinical samples (n = 21) were analysed. Our results showed deep HPV genome-wide sequencing coverage. Chromosomal integration breakpoints and large deletions were identified in HPV positive cell lines and in one clinical sample. HPV genomic variability was observed in all samples allowing identification of low frequency variants. In contrast to other approaches, TaME-seq proved to be highly efficient in HPV target enrichment, leading to reduced sequencing costs. Comprehensive studies on HPV intra-host variability generated during a persistent infection will improve our understanding of viral carcinogenesis. Efficient identification of both HPV variability and integration sites will be important for the study of HPV evolution and adaptability and may be an important tool for use in cervical cancer diagnostics.


Assuntos
Alphapapillomavirus/genética , Reação em Cadeia da Polimerase Multiplex/métodos , Infecções por Papillomavirus/virologia , Alphapapillomavirus/fisiologia , Pontos de Quebra do Cromossomo , Feminino , Variação Genética , Genoma Viral , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/fisiologia , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/fisiologia , Humanos , Infecções por Papillomavirus/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/virologia , Integração Viral
10.
Papillomavirus Res ; 5: 180-191, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29723682

RESUMO

Human papillomaviruses (HPVs) co-evolve slowly with the human host and each HPV genotype displays epithelial tropisms. We assessed the evolution of intra HPV genotype variants within samples, and their association to anogenital site, cervical cytology and HIV status. Variability in the L1 gene of 35 HPV genotypes was characterized phylogenetically using maximum likelihood, and portrayed by phenotype. Up to a thousand unique variants were identified within individual samples. In-depth analyses of the most prevalent genotypes, HPV16, HPV18 and HPV52, revealed that the high diversity was dominated by a few abundant variants. This suggests high intra-host mutation rates. Clades of HPV16, HPV18 and HPV52 were associated to anatomical site and HIV co-infection. Particularly, we observed that one HPV16 clade was specific to vaginal cells and one HPV52 clade was specific to anal cells. One major HPV52 clade, present in several samples, was strongly associated with cervical neoplasia. Overall, our data suggest that tissue tropism and HIV immunosuppression are strong shapers of HPV evolution.


Assuntos
Alphapapillomavirus/genética , Variação Genética , Tropismo Viral/genética , Adulto , Alphapapillomavirus/classificação , Canal Anal/citologia , Canal Anal/virologia , Proteínas do Capsídeo/genética , Colo do Útero/citologia , Colo do Útero/virologia , Coinfecção/virologia , Evolução Molecular , Feminino , Genótipo , Infecções por HIV/complicações , Humanos , Mutação , Proteínas Oncogênicas Virais/genética , Infecções por Papillomavirus/virologia , Filogenia , Vagina/citologia , Vagina/virologia , Adulto Jovem
12.
Lung ; 194(1): 125-35, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26463840

RESUMO

BACKGROUND: Asbestos is a carcinogen linked to malignant mesothelioma (MM) and lung cancer. Some gene aberrations related to asbestos exposure are recognized, but many associated mutations remain obscure. We performed exome sequencing to determine the association of previously known mutations (driver gene mutations) with asbestos and to identify novel mutations related to asbestos exposure in lung adenocarcinoma (LAC) and MM. METHODS: Exome sequencing was performed on DNA from 47 tumor tissues of MM (21) and LAC (26) patients, 27 of whom had been asbestos-exposed (18 MM, 9 LAC). In addition, 9 normal lung/blood samples of LAC were sequenced. Novel mutations identified from exome data were validated by amplicon-based deep sequencing. Driver gene mutations in BRAF, EGFR, ERBB2, HRAS, KRAS, MET, NRAS, PIK3CA, STK11, and ephrin receptor genes (EPHA1-8, 10 and EPHB1-4, 6) were studied for both LAC and MM, and in BAP1, CUL1, CDKN2A, and NF2 for MM. RESULTS: In asbestos-exposed MM patients, previously non-described NF2 frameshift mutation (one) and BAP1 mutations (four) were detected. Exome data mining revealed some genes potentially associated with asbestos exposure, such as MRPL1 and SDK1. BAP1 and COPG1 mutations were seen exclusively in MM. Pathogenic KRAS mutations were common in LAC patients (42 %), both in non-exposed (n = 5) and exposed patients (n = 6). Pathogenic BRAF mutations were found in two LACs. CONCLUSION: BAP1 mutations occurred in asbestos-exposed MM. MRPL1, SDK1, SEMA5B, and INPP4A could possibly serve as candidate genes for alterations associated with asbestos exposure. KRAS mutations in LAC were not associated with asbestos exposure.


Assuntos
Adenocarcinoma/genética , Exoma/genética , Neoplasias Pulmonares/genética , Mesotelioma/genética , Neoplasias Peritoneais/genética , Neoplasias Pleurais/genética , Amianto/efeitos adversos , Moléculas de Adesão Celular/genética , Proteína Coatomer/genética , Análise Mutacional de DNA , Receptores ErbB/genética , Feminino , Humanos , Masculino , Glicoproteínas de Membrana/genética , Mesotelioma Maligno , Proteínas Mitocondriais/genética , Peptídeo Sintases/genética , Monoéster Fosfórico Hidrolases/genética , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptores da Família Eph/genética , Proteínas Ribossômicas/genética , Semaforinas/genética , Proteínas Supressoras de Tumor/genética , Ubiquitina Tiolesterase/genética
13.
Haematologica ; 100(1): 91-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25281507

RESUMO

T-cell large granular lymphocytic leukemia and chronic lymphoproliferative disorder of natural killer cells are intriguing entities between benign and malignant lymphoproliferation. The molecular pathogenesis has partly been uncovered by the recent discovery of somatic activating STAT3 and STAT5b mutations. Here we show that 43% (75/174) of patients with T-cell large granular lymphocytic leukemia and 18% (7/39) with chronic lymphoproliferative disorder of natural killer cells harbor STAT3 mutations when analyzed by quantitative deep amplicon sequencing. Surprisingly, 17% of the STAT3-mutated patients carried multiple STAT3 mutations, which were located in different lymphocyte clones. The size of the mutated clone correlated well with the degree of clonal expansion of the T-cell repertoire analyzed by T-cell receptor beta chain deep sequencing. The analysis of sequential samples suggested that current immunosuppressive therapy is not able to reduce the level of the mutated clone in most cases, thus warranting the search for novel targeted therapies. Our findings imply that the clonal landscape of large granular lymphocytic leukemia is more complex than considered before, and a substantial number of patients have multiple lymphocyte subclones harboring different STAT3 mutations, thus mimicking the situation in acute leukemia.


Assuntos
Artrite Reumatoide/genética , Biomarcadores/análise , Evolução Clonal/genética , Leucemia Linfocítica Granular Grande/genética , Mutação/genética , Fator de Transcrição STAT3/genética , Linfócitos T/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Seguimentos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/metabolismo , Células Matadoras Naturais/patologia , Leucemia Linfocítica Granular Grande/tratamento farmacológico , Leucemia Linfocítica Granular Grande/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Adulto Jovem
14.
Genes Chromosomes Cancer ; 52(12): 1141-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24123310

RESUMO

Non-small cell lung carcinoma (NSCLC) is the most common subtype of lung cancer. The oncogenic potential of receptor tyrosine kinases (RTKs) is widely known and they are potential targets for tailored therapy. Ephrin receptors (Ephs) form the largest group of RTKs. Nevertheless, Ephs are not widely studied in NSCLC so far. The aim of our study was to investigate novel mutations of Eph genes (EPHA1-8, EPHB1-4, EPHB6) and their association with clinically relevant mutations in BRAF, EML4-ALK, EGFR, INSR, KDR, KRAS, MET, PDGFRA, PDGFRB, PIK3, PTEN, RET, and TP53 in NSCLC patients. Targeted resequencing was conducted on 81 formalin-fixed, paraffin-embedded NSCLC tumor specimens. We analyzed missense and nonsense mutations harbored in the coding regions of the selected genes. We found 18 novel mutations of Ephs in 20% (16 of 81) of the patients. Nearly half of these mutations occurred in the protein kinase domain. The mutations were not mutually exclusive with other clinically relevant mutations. Our study shows that Ephs are frequently mutated in NSCLC patients, and occur together with other known mutations relevant to the pathogenicity of NSCLC.


Assuntos
Adenocarcinoma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , Receptores da Família Eph/genética , Adenocarcinoma/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Códon sem Sentido , Fixadores , Formaldeído , Humanos , Neoplasias Pulmonares/patologia , Mutação de Sentido Incorreto , Inclusão em Parafina , Receptores da Família Eph/metabolismo
15.
Cancer Discov ; 3(12): 1416-29, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24056683

RESUMO

UNLABELLED: We present an individualized systems medicine (ISM) approach to optimize cancer drug therapies one patient at a time. ISM is based on (i) molecular profiling and ex vivo drug sensitivity and resistance testing (DSRT) of patients' cancer cells to 187 oncology drugs, (ii) clinical implementation of therapies predicted to be effective, and (iii) studying consecutive samples from the treated patients to understand the basis of resistance. Here, application of ISM to 28 samples from patients with acute myeloid leukemia (AML) uncovered five major taxonomic drug-response subtypes based on DSRT profiles, some with distinct genomic features (e.g., MLL gene fusions in subgroup IV and FLT3-ITD mutations in subgroup V). Therapy based on DSRT resulted in several clinical responses. After progression under DSRT-guided therapies, AML cells displayed significant clonal evolution and novel genomic changes potentially explaining resistance, whereas ex vivo DSRT data showed resistance to the clinically applied drugs and new vulnerabilities to previously ineffective drugs. SIGNIFICANCE: Here, we demonstrate an ISM strategy to optimize safe and effective personalized cancer therapies for individual patients as well as to understand and predict disease evolution and the next line of therapy. This approach could facilitate systematic drug repositioning of approved targeted drugs as well as help to prioritize and de-risk emerging drugs for clinical testing.


Assuntos
Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Medicina de Precisão/métodos , Antineoplásicos/farmacologia , Progressão da Doença , Reposicionamento de Medicamentos , Perfilação da Expressão Gênica , Genoma Humano , Humanos , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
16.
Blood ; 122(14): 2453-9, 2013 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23926297

RESUMO

Large granular lymphocyte leukemia (LGL) is often associated with immune cytopenias and can cooccur in the context of aplastic anemia (AA) and myelodysplastic syndromes (MDS). We took advantage of the recent description of signal transducer and activator of transcription 3 (STAT3) mutations in LGL clonal expansions to test, using sensitive methods, for the presence of these mutations in a large cohort of 367 MDS and 140 AA cases. STAT3 clones can be found not only in known LGL concomitant cases, but in a small proportion of unsuspected ones (7% AA and 2.5% MDS). In STAT3-mutated AA patients, an interesting trend toward better responses of immunosuppressive therapy and an association with the presence of human leukocyte antigen-DR15 were found. MDSs harboring a STAT3 mutant clone showed a lower degree of bone marrow cellularity and a higher frequency of developing chromosome 7 abnormalities. STAT3-mutant LGL clones may facilitate a persistently dysregulated autoimmune activation, responsible for the primary induction of bone marrow failure in a subset of AA and MDS patients.


Assuntos
Anemia Aplástica/genética , Leucemia Linfocítica Granular Grande/genética , Mutação , Síndromes Mielodisplásicas/genética , Fator de Transcrição STAT3/genética , Adulto , Anemia Aplástica/complicações , Anemia Aplástica/mortalidade , Separação Celular , Feminino , Citometria de Fluxo , Humanos , Estimativa de Kaplan-Meier , Leucemia Linfocítica Granular Grande/complicações , Leucemia Linfocítica Granular Grande/mortalidade , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/complicações , Síndromes Mielodisplásicas/mortalidade , Modelos de Riscos Proporcionais , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Blood ; 121(22): 4541-50, 2013 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-23596048

RESUMO

Large granular lymphocytic (LGL) leukemia is characterized by clonal expansion of cytotoxic T cells or natural killer cells. Recently, somatic mutations in the signal transducer and activator of transcription 3 (STAT3) gene were discovered in 28% to 40% of LGL leukemia patients. By exome and transcriptome sequencing of 2 STAT3 mutation-negative LGL leukemia patients, we identified a recurrent, somatic missense mutation (Y665F) in the Src-like homology 2 domain of the STAT5b gene. Targeted amplicon sequencing of 211 LGL leukemia patients revealed 2 additional patients with STAT5b mutations (N642H), resulting in a total frequency of 2% (4 of 211) of STAT5b mutations across all patients. The Y665F and N642H mutant constructs increased the transcriptional activity of STAT5 and tyrosine (Y694) phosphorylation, which was also observed in patient samples. The clinical course of the disease in patients with the N642H mutation was aggressive and fatal, clearly different from typical LGL leukemia with a relatively favorable outcome. This is the first time somatic STAT5 mutations are discovered in human cancer and further emphasizes the role of STAT family genes in the pathogenesis of LGL leukemia.


Assuntos
Leucemia Linfocítica Granular Grande/genética , Fator de Transcrição STAT5/genética , Domínios de Homologia de src/genética , Idoso , Estudos de Coortes , Dimerização , Exoma/genética , Feminino , Testes Genéticos , Células HeLa , Humanos , Masculino , Pessoa de Meia-Idade , Mutagênese , Mutação , Fosforilação/genética , Estrutura Terciária de Proteína , Fator de Transcrição STAT5/química , Fator de Transcrição STAT5/metabolismo , Transcrição Gênica/genética , Proteínas Supressoras de Tumor/genética
18.
Genes Chromosomes Cancer ; 52(5): 503-11, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23362162

RESUMO

The development of tyrosine kinase inhibitor treatments has made it important to test cancer patients for clinically significant gene mutations that influence the benefit of treatment. Targeted next-generation sequencing (NGS) provides a promising method for diagnostic purposes by enabling the simultaneous detection of multiple mutations in various genes in a single test. The aim of our study was to screen EGFR, KRAS, and BRAF mutations by targeted NGS and commonly used real-time polymerase chain reaction (PCR) methods to evaluate the feasibility of targeted NGS for the detection of the mutations. Furthermore, we aimed to identify potential novel mutations by targeted NGS. We analyzed formalin-fixed, paraffin-embedded (FFPE) tumor tissue specimens from 81 non-small cell lung carcinoma patients. We observed a significant concordance (from 96.3 to 100%) of the EGFR, KRAS, and BRAF mutation detection results between targeted NGS and real-time PCR. Moreover, targeted NGS revealed seven nonsynonymous single-nucleotide variations and one insertion-deletion variation in EGFR not detectable by the real-time PCR methods. The potential clinical significance of these variants requires elucidation in future studies. Our results support the use of targeted NGS in the screening of EGFR, KRAS, and BRAF mutations in FFPE tissue material.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA/métodos , Feminino , Fixadores/química , Formaldeído/química , Estudos de Associação Genética , Testes Genéticos/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mutação INDEL , Masculino , Pessoa de Meia-Idade , Técnicas de Diagnóstico Molecular , Inclusão em Parafina , Proteínas Proto-Oncogênicas p21(ras) , Reação em Cadeia da Polimerase em Tempo Real
19.
N Engl J Med ; 366(20): 1905-13, 2012 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-22591296

RESUMO

BACKGROUND: T-cell large granular lymphocytic leukemia is a rare lymphoproliferative disorder characterized by the expansion of clonal CD3+CD8+ cytotoxic T lymphocytes (CTLs) and often associated with autoimmune disorders and immune-mediated cytopenias. METHODS: We used next-generation exome sequencing to identify somatic mutations in CTLs from an index patient with large granular lymphocytic leukemia. Targeted resequencing was performed in a well-characterized cohort of 76 patients with this disorder, characterized by clonal T-cell-receptor rearrangements and increased numbers of large granular lymphocytes. RESULTS: Mutations in the signal transducer and activator of transcription 3 gene (STAT3) were found in 31 of 77 patients (40%) with large granular lymphocytic leukemia. Among these 31 patients, recurrent mutational hot spots included Y640F in 13 (17%), D661V in 7 (9%), D661Y in 7 (9%), and N647I in 3 (4%). All mutations were located in exon 21, encoding the Src homology 2 (SH2) domain, which mediates the dimerization and activation of STAT protein. The amino acid changes resulted in a more hydrophobic protein surface and were associated with phosphorylation of STAT3 and its localization in the nucleus. In vitro functional studies showed that the Y640F and D661V mutations increased the transcriptional activity of STAT3. In the affected patients, downstream target genes of the STAT3 pathway (IFNGR2, BCL2L1, and JAK2) were up-regulated. Patients with STAT3 mutations presented more often with neutropenia and rheumatoid arthritis than did patients without these mutations. CONCLUSIONS: The SH2 dimerization and activation domain of STAT3 is frequently mutated in patients with large granular lymphocytic leukemia; these findings suggest that aberrant STAT3 signaling underlies the pathogenesis of this disease. (Funded by the Academy of Finland and others.).


Assuntos
Leucemia Linfocítica Granular Grande/genética , Fator de Transcrição STAT3/genética , Idoso , Exoma , Expressão Gênica , Humanos , Masculino , Mutação , Receptores de Antígenos de Linfócitos T , Análise de Sequência de RNA , Transcrição Gênica , Regulação para Cima
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