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1.
Blood ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38754046

RESUMO

Chronic lymphocytic leukemia (CLL) progression during Bruton tyrosine kinase (BTK) inhibitor treatment is typically characterized by emergent B-cell receptor pathway mutations. Using peripheral blood samples from relapsed/refractory CLL patients in ELEVATE-RR (NCT02477696) (median 2 prior therapies), we report clonal evolution data for patients progressing on acalabrutinib or ibrutinib (median follow-up 41 months). Paired (baseline and progression) samples were available for 47 (excluding 1 Richter) acalabrutinib-treated and 30 (excluding 6 Richter) ibrutinib-treated patients. At progression, emergent BTK mutations were observed in 31 (66%) acalabrutinib-treated and 11 (37%) ibrutinib-treated patients (median variant allele fraction [VAF]: 16.1% vs 15.6%). BTK C481S mutations were most common in both groups; T474I (n = 9; 8 co-occurring with C481) and the novel E41V mutation within the pleckstrin homology domain of BTK (n = 1) occurred with acalabrutinib, while neither mutation occurred with ibrutinib. L528W and A428D co-mutations presented in one ibrutinib-treated patient. Pre-existing TP53 mutations were present in 25 (53.2%) acalabrutinib-treated and 16 (53.3%) ibrutinib-treated patients at screening. Emergent TP53 mutations occurred with acalabrutinib and ibrutinib (13% vs 7%; median VAF: 6.0% vs 37.3%, respectively). Six acalabrutinib-treated patients and one ibrutinib-treated patient had emergent TP53/BTK co-mutations. Emergent PLCG2 mutations occurred in 3 (6%) acalabrutinib-treated and 6 (20%) ibrutinib-treated patients. One acalabrutinib-treated patient and 4 ibrutinib-treated patients had emergent BTK/PLCG2 co-mutations. While common BTK C481 mutations were observed with both treatments, patterns of mutation and co-mutation frequency, mutation VAF, and uncommon BTK variants varied with acalabrutinib (T474I and E41V) and ibrutinib (L528W, A428D) in this patient population.

2.
J Mol Diagn ; 26(2): 140-149, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38008285

RESUMO

Detection of cancer-associated gene fusions is crucial for diagnosis, prognosis, and treatment selection. Many bioinformatics tools are available for the detection of fusion transcripts by RNA sequencing, but there are fewer well-validated software tools for DNA next-generation sequencing (NGS). A 542-gene solid tumor NGS panel was designed, with exonic probes supplemented with intronic bait probes against genes commonly involved in oncogenic fusions, with a focus on lung cancer. Three software tools for the detecting gene fusions in this DNA-NGS panel were selected and evaluated. The performance of these tools was compared after a pilot study, and each was configured for optimal batch analysis and detection rate. A blacklist for filtering common tool-specific artifacts, and criteria for selecting clinically reportable fusions, were established. Visualization tools for annotating and confirming somatic fusions were applied. Subsequently, a full clinical validation was used for comparing the results to those from in situ hybridization and/or RNA sequencing. With JuLI, Factera, and GeneFuse, 94.1%, 88.2%, and 66.7% of expected fusions were detected, respectively. With a combinatorial pipeline (termed FindDNAFusion), developed by integrating fusion-calling tools with methods for fusion filtering, annotating, and flagging reportable calls, the accuracy of detection of intron-tiled genes was improved to 98.0%. FindDNAFusion is an accurate and efficient tool in detecting somatic fusions in DNA-NGS panels with intron-tiled bait probes when RNA is unavailable.


Assuntos
Neoplasias Pulmonares , Software , Humanos , Projetos Piloto , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Fusão Gênica , DNA , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Genômica/métodos
3.
Bioorg Chem ; 82: 109-116, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30312865

RESUMO

Various 1,2,4 trisubstituted imidazolin-5-one derivatives were synthesized and evaluated for their inhibitory activity against p38 mitogen-activated protein kinase (p38MAPK) and carbonic anhydrase (CA) enzymes aiming to explore potential dual inhibitors. Results revealed that compounds 3c, 3g, 3h, 4a, 6c and 6d were the most effective derivatives against p38αMAPK (IC50 = 0.14, 0.14, 0.056, 0.14, 0.13 and 0.14 µM, respectively) compared to sorafenib (IC50 = 1.58 µM) as standard drug. On the other hand, compound 4a revealed the best inhibitory activity against all the tested carbonic anhydrase isoforms CA I, II, IV and IX with Ki values of 95.0, 0.83, 6.90 and 12.4 nM, respectively compared to acetazolamide with Ki values 250, 12.1, 74 and 12.8 nM, respectively. Therefore, compound 4a can be considered as a potent dual p38αMAPK/CA inhibitor.


Assuntos
Inibidores da Anidrase Carbônica/química , Imidazolinas/química , Inibidores de Proteínas Quinases/química , Sulfonamidas/química , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Inibidores da Anidrase Carbônica/síntese química , Anidrases Carbônicas/metabolismo , Ensaios Enzimáticos , Humanos , Imidazolinas/síntese química , Isoenzimas/metabolismo , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Relação Estrutura-Atividade , Sulfonamidas/síntese química
4.
Neuro Oncol ; 19(1): 31-42, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27416954

RESUMO

BACKGROUND: Astroblastomas (ABs) are rare glial tumors showing overlapping features with astrocytomas, ependymomas, and sometimes other glial neoplasms, and may be challenging to diagnose. METHODS: We examined clinical, histopathological, and molecular features in 28 archival formalin-fixed, paraffin-embedded AB cases and performed survival analyses using Cox proportional hazards and Kaplan-Meier methods. RESULTS: Unlike ependymomas and angiocentric gliomas, ABs demonstrate abundant distinctive astroblastic pseudorosettes and are usually Olig2 immunopositive. They also frequently exhibit rhabdoid cells, multinucleated cells, and eosinophilic granular material. They retain immunoreactivity to alpha thalassemia/mental retardation syndrome X-linked, are immunonegative to isocitrate dehydrogenase-1 R132H mutation, and only occasionally show MGMT promoter hypermethylation differentiating them from many diffuse gliomas. Like pleomorphic xanthoastrocytoma, ganglioglioma, supratentorial pilocytic astrocytoma, and other predominantly cortical-based glial tumors, ABs often harbor the BRAFV600E mutation, present in 38% of cases tested (n = 21), further distinguishing those tumors from ependymomas and angiocentric gliomas. Factors correlating with longer patient survival included age less than 30 years, female gender, absent BRAFV600E , and mitotic index less than 5 mitoses/10 high-power fields; however, only the latter was significant by Cox and Kaplan-Meier analyses (n = 24; P = .024 and .012, respectively). This mitotic cutoff is therefore currently the best criterion to stratify tumors into low-grade ABs and higher-grade anaplastic ABs. CONCLUSIONS: In addition to their own characteristic histological features, ABs share some molecular and histological findings with other, possibly ontologically related, cortical-based gliomas of mostly children and young adults. Importantly, the presence of BRAFV600E mutations in a subset of ABs suggests potential clinical utility of targeted anti-BRAF therapy.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/patologia , Córtex Cerebral/patologia , Mutação/genética , Neoplasias Neuroepiteliomatosas/patologia , Proteínas Proto-Oncogênicas B-raf/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/genética , Córtex Cerebral/metabolismo , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias Neuroepiteliomatosas/genética , Prognóstico , Taxa de Sobrevida , Adulto Jovem
5.
Int J Environ Res Public Health ; 11(9): 9491-502, 2014 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-25222473

RESUMO

Cigarette smoking is one of the most significant public health issues and the most common environmental cause of preventable cancer deaths worldwide. EGFR (Epidermal Growth Factor Receptor)-targeted therapy has been used in the treatment of LC (lung cancer), mainly caused by the carcinogens in cigarette smoke, with variable success. Presence of mutations in the KRAS (Kirsten rat sarcoma viral oncogene homolog) driver oncogene may confer worse prognosis and resistance to treatment for reasons not fully understood. NQO1 (NAD(P)H:quinone oxidoreductase), also known as DT-diaphorase, is a major regulator of oxidative stress and activator of mitomycins, compounds that have been targeted in over 600 pre-clinical trials for treatment of LC. We sequenced KRAS and investigated expression of NQO1 and five clinically relevant proteins (DNMT1, DNMT3a, ERK1/2, c-MET, and survivin) in 108 patients with non-small cell lung carcinoma (NSCLC). NQO1, ERK1/2, DNMT1, and DNMT3a but not c-MET and survivin expression was significantly more frequent in patients with KRAS mutations than those without, suggesting the following: (1) oxidative stress may play an important role in the pathogenesis, worse prognosis, and resistance to treatment reported in NSCLC patients with KRAS mutations, (2) selecting patients based on their KRAS mutational status for future clinical trials may increase success rate, and (3) since oxidation of nucleotides also specifically induces transversion mutations, the high rate of KRAS transversions in lung cancer patients may partly be due to the increased oxidative stress in addition to the known carcinogens in cigarette smoke.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Regulação da Expressão Gênica , NAD(P)H Desidrogenase (Quinona)/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Idoso , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , NAD(P)H Desidrogenase (Quinona)/metabolismo , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Fumar , Proteínas ras/metabolismo
6.
Int J Environ Res Public Health ; 11(9): 8645-60, 2014 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-25158139

RESUMO

Lung cancer (LC) and colorectal cancer (CRC) are the first and second deadliest types of cancer worldwide. EGFR-based therapy has been used in the treatment of these cancers with variable success. Presence of mutations in the KRAS driver oncogene, possibly induced by environmental factors such as carcinogens in diet and cigarette smoke, may confer worse prognosis and resistance to treatment for reasons not fully understood. Data on possible associations between KRAS mutational status and clinical and metabolic parameters, which may help in clinical management, as well as in identifying risk factors for developing these cancers, are limited in the current literature. We sequenced the KRAS gene and investigated the associations of variations in 108 patients with non-small cell lung carcinoma (NSCLC), the most common form of LC, and in 116 patients with CRC. All of the mutations originated from the guanosine nucleotide and over half of all transversions in NSCLC and CRC were c.34 G>T and c.35 G>T, respectively. c.35 G>A was the most frequent type of transition in both cancers. Excluding smoking, the clinical and metabolic parameters in patients carrying mutant and wild type KRAS were similar except that the CRC patients with transversion mutations were 8.6 years younger than those carrying the transitions (P < 0.01). Dyslipidemia, hypertension, family cancer history, and age of diagnosis older than 60 years were more frequent in NSCLC than CRC (P ≤ 0.04). These results suggest that most of the clinical and metabolic parameters investigated in this study are probably not associated with the more aggressive phenotype and differences in response to EGFR-based treatment previously reported in patients with KRAS mutations. However, the increased rates of abnormal metabolic parameters in patients with NSCLC in comparison to CRC indicate that these parameters may be more important in the management of NSCLC. CRC patients carrying transition mutations are older than those carrying transversions, suggesting that age may determine the type of KRAS mutation in CRC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Colorretais/patologia , Neoplasias Colorretais/fisiopatologia , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/etiologia , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas p21(ras) , Proteínas ras/metabolismo
8.
Int J Cancer ; 125(3): 603-11, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19405126

RESUMO

Gene amplification, a common mechanism for oncogene activation in cancers, has been used in the discovery of novel oncogenes. Low-level copy number gains are frequently observed in head and neck squamous cell carcinomas (HNSCCs) where numerous amplification events and potential oncogenes have already been reported. Recently, we applied restriction landmark genome scanning to study gene amplifications in HNSCC and located novel and uncharacterized regions in primary tumor samples. Gain on chromosome 8q22.3, the location of YWHAZ (14-3-3zeta), is found in 30-40% HNSCC cases. Data obtained from fluorescence in situ hybridization and immunohistochemistry on HNSCC tissue microarrays confirmed frequent low-level YWHAZ copy number gain and protein overexpression. YWHAZ mRNA was frequently upregulated in patients' tumor tissues. Furthermore, YWHAZ RNAi significantly suppressed the growth rate of HNSCC cell lines, and overexpression of YWHAZ in HaCaT immortalized human skin keratinocytes promotes overgrowth, as well as morphological changes. Reduced YWHAZ levels increased the G1/G0-phase proportion, decreased the S-phase proportion and the rate of DNA synthesis. Based on this evidence, we suggest that YWHAZ is a candidate proto-oncogene and deserves further investigation into its role in HNSCC carcinogenesis.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias de Cabeça e Pescoço/genética , Chaperonas Moleculares/genética , Proteínas 14-3-3 , Adulto , Idoso , Western Blotting , DNA de Neoplasias/metabolismo , Feminino , Dosagem de Genes , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Regulação para Cima
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 68(5): 1244-9, 2007 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-17376736

RESUMO

A simple and rapid spectrophotometric method has been developed for the determination of tricyclic anti-depressant drugs such as trazodone (TZH), amineptine (APH) and amitriptyline (ATPH) hydrochlorides in pure form and in different pharmaceutical preparations. The charge transfer (CT) reaction between TZH, APH and ATPH as electron donors and TCNQ as electron acceptor was utilized for their spectrophotometric determination. The optimum experimental conditions, like time, temperature, stoichiometry, solvents, for the CT complex formation are established. The method permits the determination of TZH, APH and ATPH over a concentration range of 10-400, 10-440 and 10-300 microg ml(-1), respectively. The sensitivity (S) is found to be 0.09, 0.087 and 0.069 g cm(-2) for TZH, APH and ATPH, respectively. The SD values are found to be 0.146-0.293, 0.154-0.285 and 0.091-0.212 and RSD values are 0.142-1.92, 0.297-1.92 and 0.212-0.915 for TZH, APH and ATPH, respectively. The low values of the relative standard deviation indicate the high accuracy and precision of the method. The mean recovery values obtained together with a high correlation coefficient values, amount in the range 98-101.5, 98.7-102.9 and 93-101.9 for TZH, APH and ATPH, respectively. The method is applicable for the assay of the investigated drugs in different dosage forms and the results are in good agreement with those obtained by the official method.


Assuntos
Amitriptilina/análise , Antidepressivos Tricíclicos/análise , Dibenzocicloeptenos/análise , Nitrilas/química , Trazodona/análise , Amitriptilina/química , Antidepressivos Tricíclicos/química , Dibenzocicloeptenos/química , Preparações Farmacêuticas/química , Solventes , Espectrofotometria , Temperatura , Fatores de Tempo , Trazodona/química
10.
Artigo em Inglês | MEDLINE | ID: mdl-16829178

RESUMO

Extraction spectrophotometric method has been developed for the determination of tricyclic drugs such as trazodone (TZH), amineptine (APH) and amitriptyline (ATPH) hydrochlorides in pure form and in the dosage forms coming from different Egyptian markets. The method based on the formation of ion-pairs between these drugs under investigation and inorganic complex of Mo(V)-thiocyanate followed by its extraction with methylene chloride. The optimum conditions for the ion-pairs formation are established. The method permits the determination of TZH, APH and ATPH over the concentration range of 2-28, 2-32 and 1-30 microg ml(-1), respectively. The Sandell sensitivity (S) is found to be 0.105, 0.138 and 0.118 g cm(-2) for TZH, APH and ATPH, respectively. The SD is found to be 0.16-0.377, 0.12-0.259 and 0.091-0.286 and the R.S.D. are 0.14-0.55, 0.12-0.399 and 0.095-0.485 for TZH, APH and ATPH, respectively. The method is applicable for the assay of the investigated drugs in different dosage forms and the results are in good agreement with those obtained by the official method.


Assuntos
Amitriptilina/química , Dibenzocicloeptenos/química , Ácido Clorídrico/química , Molibdênio/química , Tiocianatos/química , Trazodona/química , Absorção/efeitos dos fármacos , Antidepressivos Tricíclicos/química , Ácido Ascórbico/farmacologia , Relação Dose-Resposta a Droga , Concentração de Íons de Hidrogênio , Modelos Biológicos , Molibdênio/farmacologia , Solventes/farmacologia , Espectrofotometria/métodos , Temperatura , Tiocianatos/farmacologia , Fatores de Tempo
11.
Artigo em Inglês | MEDLINE | ID: mdl-16527524

RESUMO

A simple and rapid extraction spectrophotometric procedure has been developed for the determination of tricyclic anti-depressant drugs such as trazodone (TZH), amineptine (APH) and amitriptyline (ATPH) hydrochlorides in pure form and in different dosage forms. The method involves the formation of intense yellow ion-pairs between these drugs under investigation and methyl orange (MO) and bromocresol green (BCG) reagents followed by their extraction with 1,2-dichloroethane and quantitative microdetermination at 420 and 410 nm using MO or BCG, respectively. The optimum experimental conditions for the ion-pairs formation are established. The method permits the determination of TZH, APH and ATPH over a concentration range of 2-50, 2-50 and 1-25 microg ml(-1) for TZH, APH and ATPH, using MO and 1-25 microg ml(-1) for TZH, APH and ATPH, using BCG, respectively. The Sandell sensitivity (S) is found to be 0.106, 0.1071 and 0.0907 g cm(-2) for TZH, APH and ATPH, respectively, using MO reagent and 0.0788, 0.0661 and 0.0494 g cm(-2) for TZH, APH and ATPH, respectively, using BCG. The method is applicable for the assay of the investigated drugs in different dosage forms and the results are in good agreement with those obtained by the official method.


Assuntos
Amitriptilina/química , Compostos Azo/química , Verde de Bromocresol/química , Dibenzocicloeptenos/química , Trazodona/química , Concentração de Íons de Hidrogênio , Indicadores e Reagentes/química , Estrutura Molecular , Preparações Farmacêuticas/química , Solventes/química , Espectrofotometria , Temperatura , Fatores de Tempo
12.
Proc Natl Acad Sci U S A ; 101(11): 3915-20, 2004 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-15007164

RESUMO

Molecular mechanisms of leukemogenesis have been successfully unraveled by studying genes involved in simple rearrangements including balanced translocations and inversions. In contrast, little is known about genes altered in complex karyotypic abnormalities. We studied acute myeloid leukemia (AML) patients with complex karyotypes and abnormal chromosome 21. High-resolution bacterial artificial chromosome (BAC) array-based comparative genomic hybridization disclosed amplification predominantly in the 25- to 30-megabase (MB) region that harbors the APP gene (26.3 MB) and at position 38.7-39.1 MB that harbors the transcription factors ERG and ETS2. Using oligonucleotide arrays, APP was by far the most overexpressed gene (mean fold change 19.74, P = 0.0003) compared to a control group of AML with normal cytogenetics; ERG and ETS2 also ranked among the most highly expressed chromosome 21 genes. Overexpression of APP and ETS2 correlated with genomic amplification, but high APP expression occurred even in a subset of AML patients with normal cytogenetics (10 of 64, 16%). APP encodes a glycoprotein of unknown function previously implicated in Alzheimer's disease, but not in AML. We hypothesize that APP and the transcription factors ERG and ETS2 are altered by yet unknown molecular mechanisms involved in leukemogenesis. Our results highlight the value of molecularly dissecting leukemic cells with complex karyotypes.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 21 , Proteínas de Ligação a DNA , Leucemia Mieloide/genética , Proteínas Repressoras , Doença Aguda , Precursor de Proteína beta-Amiloide/biossíntese , Precursor de Proteína beta-Amiloide/genética , Dosagem de Genes , Humanos , Leucemia Mieloide/metabolismo , Proteínas Oncogênicas/biossíntese , Proteínas Oncogênicas/genética , Proteína Proto-Oncogênica c-ets-2 , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transativadores/biossíntese , Transativadores/genética , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Regulador Transcricional ERG
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