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1.
Afr Health Sci ; 23(2): 256-264, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38223583

RESUMO

Background: Ovarian cancer (OC) is the third most common cancer in women and the leading cause of death associated with gynecologic tumors. Because this disease is asymptomatic in the early stages, most patients are not diagnosed until the late stages. This highlights the need for the development of diagnostic biomarkers. MicroRNAs (miRNAs), small non-coding RNAs, are currently being explored as potential biomarkers for the early detection of various malignancies in humans. However, their expression and diagnostic value in OC have not been well studied. Materials and Methods: the plasma levels of miR-21, miR-200a, miR-200b, miR-200c, miR-205 and miR-125b were determined in epithelial ovarian cancer (EOC) patients and healthy controls by Reverse Transcription Quantitative Realtime Polymerase Chain Reaction (RT-qPCR). The expression levels of the deregulated microRNAs were analysed according to clinical characteristics. Results: It was found that miR-21 and miR-125b were upregulated in EOC compared with healthy controls. Moreover, decreased miR-125b was associated with resistance to platinum-based chemotherapy. Conclusions: Our data suggest that miR-21 and miR-125b in plasma may serve as potential circulating biomarkers for the early detection of EOC. MiR-125b may also be useful for predicting chemosensitivity in EOC patients.


Assuntos
MicroRNAs , Neoplasias Epiteliais e Glandulares , Neoplasias Ovarianas , Humanos , Feminino , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/genética , Medicina de Precisão , Biomarcadores Tumorais/genética , Neoplasias Epiteliais e Glandulares/diagnóstico , Neoplasias Epiteliais e Glandulares/genética , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , MicroRNAs/genética
2.
Clin Epigenetics ; 11(1): 138, 2019 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-31601247

RESUMO

BACKGROUND: Bisphenol A (BPA), an estrogen-like endocrine disruptor used in plastics, has been associated with development and promotion of breast cancer, so plastic manufacturers shifted towards less-studied analogs, BPF and BPS. Studying the associated DNA methylome-wide mechanisms of these derivatives is timely, particularly in comparison with BPA. METHODS: We assessed proliferation, cell cycle, and migration of breast cancer cells (estrogen receptor (ER)-positive: MCF-7 and ER-negative: MDA-MB-231) treated with BPF and BPS ± estrogen receptor inhibitor (ERI) in comparison to BPA ± ERI. RNA expression and activity of DNA (de)methylation enzymes and LINE-1 methylation were quantified. DNA methylome-wide analysis was evaluated in bisphenol-exposed cells and compared to clinical breast cancer data. RESULTS: The three bisphenols caused ER-dependent increased proliferation and migration of MCF-7 but not MDA-MB-231 cells, with BPS being 10 times less potent than BPA and BPF. Although they have similar chemical structures, the three bisphenols induced differential DNA methylation alterations at several genomic clusters of or single CpG sites, with the majority of these being ER-dependent. At equipotent doses, BPA had the strongest effect on the methylome, followed by BPS then BPF. No pathways were enriched for BPF while BPA- and BPS-induced methylome alterations were enriched in focal adhesion, cGMP-PKG, and cancer pathways, which were also dysregulated in methylome-wide alterations comparing ER-positive breast cancer samples to adjacent normal tissues. CONCLUSIONS: The three bisphenols have important epigenetic effects in breast cell lines, with those of BPA and BPS overlapping with cancer-related pathways in clinical breast cancer models. Hence, further investigation of their safety is warranted.


Assuntos
Compostos Benzidrílicos/farmacologia , Neoplasias da Mama/genética , Metilação de DNA/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Fenóis/farmacologia , Receptores de Estrogênio/metabolismo , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ilhas de CpG/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Feminino , Adesões Focais/efeitos dos fármacos , Fulvestranto/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Elementos Nucleotídeos Longos e Dispersos/efeitos dos fármacos , Células MCF-7 , Receptores de Estrogênio/antagonistas & inibidores
4.
Int J Lab Hematol ; 37(4): 503-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25537026

RESUMO

BACKGROUND: Glanzmann thrombasthenia (GT) is a rare inherited platelet disorder that is characterized by spontaneous or postprocedural bleeding. The diagnosis of GT depends on identifying the dysfunction of the platelets. AIM: The aim of this study was to compare a whole blood impedance Multiplate analyzer (MEA) with the standard method, light transmission aggregometry (LTA) in diagnosis of GT. METHODS: Fifteen patients with GT were assessed on MEA and LTA using arachidonic acid (ASPI: 15 mm), (TRAP: 1 mm), collagen (100 µg/mL), ADP (0.2 mm), and ristocetin (Risto: 10 mg/mL). Whole blood samples were collected in sodium citrate and hirudin vacuum, blood collection tubes and tested within 4 h. Platelet-rich plasma was used for LTA using platelet agonists (ristocetin 1.5 mg/mL) (arachidonic acid 0.5 mg/mL) (ADP 2.5 mg/mL) and (collagen 1 mg/mL). RESULTS: The platelet count and PFA-100 results were (average and SD) 319 ± 93 × 10(9) L and 252 ± 34 s, respectively. Flow cytometry analysis showed that all samples are positive for CD42a and CD42b, whereas 9/15 samples were negative for CD61 and CD41. The other six patients had either partial or full expression of CD61/CD41. Aggregation analysis using both methods showed that all samples had no aggregation response to any of the agonists used apart from six samples which, using only the MEA, showed minimal aggregation in response to collagen (average = 14.3 ± 7 µg, which may suggest ability to detect qualitative abnormality of GPIIb/IIIa). CONCLUSION: These results suggest that the MEA is sensitive for the detection of Glanzmann thrombasthenia. Furthermore, MEA may also be able to differentiate between the subtypes of Glanzmann thrombasthenia.


Assuntos
Plaquetas/patologia , Testes de Função Plaquetária/instrumentação , Trombastenia/diagnóstico , Trifosfato de Adenosina/farmacologia , Adolescente , Adulto , Antígenos CD/genética , Antígenos CD/metabolismo , Ácido Araquidônico/farmacologia , Biomarcadores/metabolismo , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Criança , Pré-Escolar , Colágeno/farmacologia , Impedância Elétrica , Expressão Gênica , Humanos , Luz , Nefelometria e Turbidimetria/instrumentação , Nefelometria e Turbidimetria/normas , Agregação Plaquetária/efeitos dos fármacos , Contagem de Plaquetas , Testes de Função Plaquetária/métodos , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/genética , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Plasma Rico em Plaquetas/citologia , Receptores de Trombina/química , Ristocetina/farmacologia , Trombastenia/sangue
5.
Pathol Biol (Paris) ; 60(4): 239-45, 2012 Aug.
Artigo em Francês | MEDLINE | ID: mdl-22743097

RESUMO

Chronic myeloid leukemia (CML) is a chronic blood disorder characterized by a reciprocal translocation between chromosomes 9 and 22, leading to the creation of a chimeric gene encoding the BCR-ABL fusion protein with a constitutive tyrosine kinase activity. Although long known as a disease with an inexorable progression to acute leukemia, CML history has been significantly improved by the use of imatinib, a tyrosine kinase inhibitor. Imatinib has revolutionized the treatment of CML by transforming it from an invariably fatal disease to a chronic but manageable condition. In fact, the discovery of this class of targeted therapy had an impact not only on the survival of CML patients but also on other scientific and medical fields. This review illustrates the impact of imatinib, the first example of tyrosine kinase inhibitors on the treatment of CML, on the treatment of other cancers, the impact on health systems and on the scientific research in general.


Assuntos
Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Terapia de Alvo Molecular , Piperazinas/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Antineoplásicos/uso terapêutico , Benzamidas , Resistencia a Medicamentos Antineoplásicos , Proteínas de Fusão bcr-abl/genética , Humanos , Mesilato de Imatinib , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Translocação Genética
6.
Leukemia ; 26(3): 451-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21869839

RESUMO

The vitamin E derivative (+)α-tocopheryl succinate (α-TOS) exerts pro-apoptotic effects in a wide range of tumors and is well tolerated by normal tissues. Previous studies point to a mitochondrial involvement in the action mechanism; however, the early steps have not been fully elucidated. In a model of acute promyelocytic leukemia (APL) derived from hCG-PML-RARα transgenic mice, we demonstrated that α-TOS is as effective as arsenic trioxide or all-trans retinoic acid, the current gold standards of therapy. We also demonstrated that α-TOS induces an early dissipation of the mitochondrial membrane potential in APL cells and studies with isolated mitochondria revealed that this action may result from the inhibition of mitochondrial respiratory chain complex I. Moreover, α-TOS promoted accumulation of reactive oxygen species hours before mitochondrial cytochrome c release and caspases activation. Therefore, an in vivo antileukemic action and a novel mitochondrial target were revealed for α-TOS, as well as mitochondrial respiratory complex I was highlighted as potential target for anticancer therapy.


Assuntos
Arsenicais/uso terapêutico , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Leucemia Promielocítica Aguda/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Óxidos/uso terapêutico , Tretinoína/uso terapêutico , alfa-Tocoferol/farmacologia , alfa-Tocoferol/uso terapêutico , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Apoptose/efeitos dos fármacos , Trióxido de Arsênio , Caspases/metabolismo , Linhagem Celular Tumoral , Citocromos c/metabolismo , Modelos Animais de Doenças , Complexo II de Transporte de Elétrons/antagonistas & inibidores , Humanos , Leucemia Promielocítica Aguda/mortalidade , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Proteínas de Fusão Oncogênica/metabolismo , Estabilidade Proteica/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo , Transplante Isogênico
7.
Br J Surg ; 97(11): 1659-65, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20799288

RESUMO

BACKGROUND: The exact anatomical location of the sentinel lymph node (SLN) in the axilla has not ascertained clinically, but could be useful both for teaching purposes and to reduce the morbidity of SLN biopsy. The aim of the study was to determine the position of the SLN in the axilla and to demonstrate that this location is not random. METHODS: A consecutive series of 242 patients with stage I breast cancer (T1/T2 N0) or ductal carcinoma in situ who underwent SLN localization by peritumoral injection were included in a prospective study to map the location of the SLN in the axilla. A new anatomical classification of the lower part of the axilla based on the intersection of two anatomical landmarks, the lateral thoracic vein (LTV) and the second intercostobrachial nerve (ICBN), is described. These two constant elements form the basis of four axillary zones (A, B, C and D). RESULTS: In 98.2 per cent of patients the axillary SLN was located medially, alongside the LTV, either below the second ICBN (zone A, 86.8 per cent) or above it (zone B, 11.5 per cent). In only four patients (1.8 per cent) was the SLN located laterally in the axilla. CONCLUSION: Regardless of the site of the tumour in the breast, 98.2 per cent of SLNs were found in the medial part of the axilla, alongside the LTV. This information should help to avoid unnecessary lateral dissections.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/secundário , Linfonodos/patologia , Biópsia de Linfonodo Sentinela , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Neoplasias da Mama/cirurgia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Intraductal não Infiltrante/cirurgia , Feminino , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Estudos Prospectivos
8.
Oncogene ; 27(12): 1665-76, 2008 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-17891179

RESUMO

Constitutive activation of the NF-kappaB pathway by the Tax oncoprotein plays a crucial role in the proliferation and transformation of HTLV-I infected T lymphocytes. We have previously shown that Tax ubiquitylation on C-terminal lysines is critical for binding of Tax to IkappaB kinase (IKK) and its subsequent activation. Here, we report that ubiquitylated Tax is not associated with active cytosolic IKK subunits, but binds endogenous IKK-alpha, -beta, -gamma, targeting them to the centrosome. K63-ubiquitylated Tax colocalizes at the centrosome with IKK-gamma, while K48-ubiquitylated Tax is stabilized upon proteasome inhibition. Altogether, these results support a model in which K63-ubiquitylated Tax activates IKK in a centrosome-associated signalosome, leading to the production of Tax-free active cytoplasmic IKK. These observations highlight an unsuspected link between Tax-induced IKK activation and the centrosome.


Assuntos
Centrossomo/metabolismo , Produtos do Gene tax/metabolismo , Quinase I-kappa B/metabolismo , Transdução de Sinais/fisiologia , Ubiquitina/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Transformada , Ativação Enzimática/fisiologia , Células HeLa , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Humanos , Ligação Proteica , Subunidades Proteicas/metabolismo , Fatores de Elongação da Transcrição
9.
Virologie (Montrouge) ; 11(3): 195-205, 2007 Jun 01.
Artigo em Francês | MEDLINE | ID: mdl-37012847

RESUMO

HTLV-1 is a human retrovirus responsible for adult T-cell leukemialymphoma, a monoclonal proliferation of CD4 + T lymphocytes. In addition to the genes encoding the structural proteins and enzymes, the HTLV-1 genome encodes non structural proteins that regulate viral expression as well as various cellular machineries.Among them, Tax has rapidly been identified as the protein responsible for HTLV-1 transforming properties. Tax promotes cell proliferation by activating or repressing cellular genes and by disturbing the mechanisms that control cell division, DNA integrity and apoptosis. These multiple functions rely on the ability of Tax to recruit cytoplasmic and nuclear proteins. The mechanisms involved in the targeting of Tax toward these subcellular sites are still incompletely understood. This review describes the recent data concerning the intracellular maturation of Tax and the control of its functions through posttranslational modifications.

11.
Leukemia ; 18(3): 607-15, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14712289

RESUMO

N-(4-hydroxyphenyl)retinamide (HPR) is a synthetic retinoid that inhibits growth and induces apoptosis in many human cell lines. We explored the effects of HPR on human T-cell lymphotropic virus type I (HTLV-I)-positive and HTLV-I-negative malignant T-cell lines, most of which are resistant to all-trans retinoic acid. Clinically achievable concentrations of HPR caused a dramatic inhibition of cell proliferation, G(0)/G(1) arrest, and massive apoptosis in all tested malignant T cells, while no effect was observed on resting or activated normal lymphocytes. Interestingly, HTLV-I-negative cell lines were significantly more sensitive to HPR compared to HTLV-I-positive and Tax-transfected cells. In HTLV-I-negative cells only, HPR-induced apoptosis was associated with ceramide accumulation, sharp decrease in mitochondrial membrane potential, and activation of caspases 8, 9 and 3, and could be partially reverted by the caspase inhibitor z-VAD suggesting that Tax protects infected cells from ceramide accumulation and caspase-mediated apoptosis. In HTLV-I-positive cells, HPR treatment rapidly induced proteasomal-mediated degradation of p21, downregulated cyclin D(1), and upregulated bax protein levels. These findings support a potential therapeutic role for HPR in both HTLV-I-associated adult T-cell leukemia/lymphoma (ATL) and HTLV-I-negative peripheral T-cell lymphomas.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Transformação Celular Viral , Fenretinida/farmacologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2 , Linfócitos T/patologia , Caspases/metabolismo , Divisão Celular/efeitos dos fármacos , Linhagem Celular Transformada , Ciclina D , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Humanos , Proteínas Proto-Oncogênicas/metabolismo , Linfócitos T/metabolismo , Linfócitos T/virologia , Células Tumorais Cultivadas , Proteína X Associada a bcl-2
12.
Leuk Lymphoma ; 42(5): 1023-31, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11697619

RESUMO

We report four cases of a "T-cell-rich B-cell chronic lymphoproliferative disorder" involving the bone marrow and not extramedullary sites. The neoplastic B-cell proliferation in these cases was composed predominantly of small lymphoid cells with features of both hairy cell leukemia and lymphoplasmacytoid lymphoma. All cases presented with neutropenia and with difficulty in diagnosis. We present the clinical, morphologic, cytochemical, and immunophenotypic findings in these cases and discuss this entity.


Assuntos
Medula Óssea/patologia , Leucemia Linfocítica Crônica de Células B/diagnóstico , Linfoma de Células B/diagnóstico , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Leucemia de Células Pilosas/diagnóstico , Leucemia de Células Pilosas/patologia , Leucemia Linfocítica Crônica de Células B/patologia , Leucemia Linfocítica Crônica de Células B/terapia , Linfoma de Células B/patologia , Pessoa de Meia-Idade , Neutropenia/etiologia , Linfócitos T/citologia
13.
Can J Urol ; 8(4): 1306-13, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11564273

RESUMO

Prostate specific antigen (PSA) has been proven to be a valuable tool in the diagnosis and staging of early prostate cancer and as a sensitive marker of residual or recurrent cancer after curative therapy. In 1998, 200 000 new cases of prostate cancer were reported in the SEER database. Two-thirds of these, or 134 000 men, underwent definitive therapy for localized cancer, including approximately 75 000 radical prostatectomies. It has been reported that 20%-50% of radical prostatectomy patients will have a PSA only recurrence. One can therefore estimate that every year 15 000 to 38 000 men will have a rising PSA following definitive surgical therapy. This elevation of PSA often precedes clinical failure by many years and poses a difficult management problem for which there are not, as yet, definitive management guidelines. This paper will review the definition of PSA recurrence, the natural history, diagnostic options and the therapeutic choices, as illustrated by several genuine cases.


Assuntos
Recidiva Local de Neoplasia/diagnóstico , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/cirurgia , Adenocarcinoma/sangue , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Adenocarcinoma/terapia , Idoso , Terapia Combinada , Humanos , Imunoensaio/métodos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Estadiamento de Neoplasias , Complicações Pós-Operatórias , Prostatectomia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/terapia , Qualidade de Vida , Resultado do Tratamento
14.
Can J Urol ; 8(3): 1290-2, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11423017

RESUMO

INTRODUCTION: The traditional criteria for selecting suitability of male patients with bladder cancer for othtopic neobladder substitution includes: patient motivation, negative transurethral (TUR) prostate biopsy prior to cystectomy, and/or tumor-free biopsy of the urethral margin at the time of cystectomy. In this report we evaluate the value of these preoperative and intraoperative biopsies in the cystoscopically normal prostatic urethra. METHODS: During a 5-year period, cystectomies were performed on 54 men and 13 women with invasive bladder cancer. Prior to this procedure, all of the men had TUR biopsy of the prostate. Forty men with cystoscopically normal prostatic fossa had negative prostatic biopsies, and. had orthotopic neobladder substitution. RESULTS: Pathological examination showed that 3 out of these 40 men had transitional cell carcinoma (TCC) involving the prostate. In all 40 patients, the prostatic apical resection margin was negative. To date, none of the patients developed urethro-neobladder recurrence. CONCLUSION: TUR biopsy of the prostatic urethra prior to cystectomy, or biopsy of the prostatic urethral margin at the time of cystectomy in patients with cystoscopically normal, tumor free prostatic urethra has limited value in selecting candidates for orthotopic neobladder substitution.


Assuntos
Cistoscopia , Cuidados Pré-Operatórios , Próstata/patologia , Uretra/patologia , Neoplasias da Bexiga Urinária/cirurgia , Coletores de Urina , Adulto , Idoso , Biópsia , Feminino , Secções Congeladas , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias da Bexiga Urinária/patologia
15.
Hematol J ; 2(2): 127-35, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11424005

RESUMO

INTRODUCTION: Adult T-cell leukemia/lymphoma, caused by the human T-cell lymphotropic virus type I, is an aggressive neoplasm of mature activated T cells that is generally resistant to conventional therapy. While arsenic trioxide (As) inhibits the growth and induces apoptosis in HTLV-I-infected T cells, synergistically, when combined with interferon-alpha, variable effects on growth with all trans retinoic acid treatment have been reported in ATL-derived cell lines and fresh ATL cells. In this study, we investigate the effects of ATRA alone or in combination with As in HTLV-I-transformed cells. MATERIALS AND METHODS: Four HTLV-I-transformed cell lines (HuT-102, MT2, C8166 and C91PL) were treated with different doses of ATRA alone or in combination with As for one to three days. Cell growth was assessed by cell count with 3H-thymidine incorporation. Cell cycle distribution was assessed by propidium iodine-labeled DNA content by flow cytometry. Apoptosis was evaluated by Hoechst nuclear staining and annexin-V binding assays. Expression of retinoid receptors, the viral transactivator Tax, and the proteins bcl-2 and IkappaB-alpha proteins, was analysed by Western blot. RESULTS: Only C8166 cells were sensitive to the ATRA-induced growth inhibitory effect while HuT-102, MT2, and C91PL were resistant to ATRA treatment (up to 10(-5) M). The retinoid X receptor alpha and the retinoic acid receptor gamma (RARgamma) proteins were expressed in all four cell lines, while RARalpha protein was only detected in the HuT-102 and C8166 cells. The combination ATRA/As showed a highly synergistic effect on HuT-102 cells, and, to a lesser extent, on C8166 cells and resulted in a dramatic inhibition of cell proliferation and induction of massive apoptosis in HuT-102 cells, associated with caspase activation. While ATRA alone had no effect on Tax and IkappaB-alpha protein levels, ATRA increased the As-induced Tax degradation and the up-regulation of IkappaB-alpha protein. In contrast, the expression of bcl-2 protein was not significantly affected by any of the treatments. CONCLUSION: Our data provide a rationale for combined ATRA and As-therapies in ATL patients refractory to conventional therapy and expressing RARalpha in their leukemic cells.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Arsenicais/farmacologia , Vírus Linfotrópico T Tipo 1 Humano , Leucemia-Linfoma de Células T do Adulto/metabolismo , Óxidos/farmacologia , Linfócitos T/metabolismo , Tretinoína/farmacologia , Antineoplásicos/uso terapêutico , Trióxido de Arsênio , Arsenicais/uso terapêutico , Linhagem Celular Transformada , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Humanos , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Óxidos/uso terapêutico , Receptores do Ácido Retinoico/metabolismo , Receptor alfa de Ácido Retinoico , Linfócitos T/patologia , Linfócitos T/virologia , Tretinoína/uso terapêutico
16.
Leukemia ; 15(1): 57-61, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11243400

RESUMO

Patients with normal-karyotype acute myelogenous leukemia (NKAML) may have undetected genetic abnormalities that could affect prognosis. Screening for known AML-specific genetic abnormalities using the reverse transcription polymerase chain reaction (RT-PCR) may help in arriving at a more definitive prognosis. To test this hypothesis, 104 patients without translocation (8;21) and inversion(16), as shown by standard cytogenetic (SC) analysis, were screened for these two genetic abnormalities using RT-PCR. Western blot analysis for the AML1/ETO fusion protein and fluorescent in situ hybridization (FISH) analysis for t(8;21) were performed in patients for whom we had samples. The characteristics and outcome after high-dose cytarabine containing treatments in five patients with t(8;21) shown by RT-PCR alone were then compared to 21 patients with t(8;21) detected using SC analysis. Eight of the 104 patients had masked t(8;21) and none had masked inv(16), as shown by RT-PCR. Five of 54 patients with NKAML had a detectable AML1/ETO fusion RNA transcript. Western blot analysis showed the AML1/ETO fusion protein in four of the seven patients for whom we had samples among the eight with masked t(8;21) shown by RT-PCR. All patients with t(8;21) shown by RT-PCR had negative FISH results. Ninety percent (n=19) of the patients with t(8;21) shown by SC analysis and 40% (n= 2) of the patients with t(8;21) shown by RT-PCR alone achieved a complete remission (P value 0.03). These data suggest that the outcome of NKAML patients with t(8;21) shown by RT-PCR is not equivalent to patients with t(8;21) by SC studies.


Assuntos
Cromossomos Humanos Par 21 , Cromossomos Humanos Par 8 , Leucemia Mieloide Aguda/genética , Proteínas de Fusão Oncogênica/genética , Fatores de Transcrição/genética , Translocação Genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Subunidade alfa 2 de Fator de Ligação ao Core , Citogenética/métodos , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/fisiopatologia , Pessoa de Meia-Idade , Proteínas de Fusão Oncogênica/análise , Reação em Cadeia da Polimerase/métodos , Prognóstico , Proteína 1 Parceira de Translocação de RUNX1 , Fatores de Transcrição/análise
17.
J Med Liban ; 48(2): 59-62, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11028151

RESUMO

INTRODUCTION AND OBJECTIVES: The percentage of free over total prostate specific antigen (%F/T PSA) seems to enhance the predictive value of PSA in diagnosing prostate cancer. We evaluated the value of F/T PSA in 50 consecutive patients who underwent prostate needle biopsy, its relationship to the Gleason score and number of positive cores. MATERIAL AND METHODS: 50 patients underwent prostate needle biopsy for abnormal PSA and/or abnormal digital rectal examination (DRE). There were 8 patients with PSA equal or less than 4 ng/ml, 6 with F/T PSA < 20%, group I (GI). 27 patients with PSA between 4.1 ng/ml and 10.0 ng/ml, 20 with F/T PSA < 20%, group II (GII) and 15 patients with PSA > 10.1 ng/ml (13 with F/T PSA < 20%), group III (GIII). At least six needle biopsies were obtained guided by transrectal ultrasound selectively or randomly. Pathological evaluation included Gleason grade and number of cores involved. RESULTS: 21/50 patients (42%) had positive biopsies, 3/8 in GI, 8/27 in GII (6 had negative DRE) and 10/15 in GIII (9 had positive DRE). 19/21 patients with positive biopsies had F/T PSA < 20%. The sensitivity, specificity and positive predictive value of PSA between 4-10 ng/ml and F/T PSA < 20% was 87.5%, 31% and 35% respectively. Stratifying patients with positive biopsies to F/T PSA < 10%, F/T PSA > 10% and the three PSA groups, there was no relationship to either Gleason score or number of positive cores. CONCLUSION: With a cutoff of 20%, F/T PSA seems to be an important parameter in selecting patients with abnormal PSA for biopsy. It will be helpful mostly with PSA 4-10 ng/ml. No relationship was observed between the level of F/T PSA, grade or number of positive cores.


Assuntos
Antígeno Prostático Específico/sangue , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Biópsia por Agulha , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Neoplasias da Próstata/patologia
18.
Blood ; 96(8): 2849-55, 2000 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11023521

RESUMO

Human T-cell lymphotropic virus type I (HTLV-I)-associated adult T-cell leukemia/lymphoma (ATL) is a malignancy of mature activated T cells resistant to conventional chemotherapy. The viral transactivator protein Tax plays a critical role in HTLV-I-induced transformation and apoptosis resistance by inducing I kappa B-alpha degradation, resulting in the activation of the NF-kappa Bpathway. In these HTLV-I-transformed cells, arsenic trioxide (As) and interferon (IFN)-alpha synergize to induce cell cycle arrest and apoptosis. We demonstrate that cell death induction is only partly dependent upon caspase activation and is not associated with modulation of bcl-2, bax, or p53 expression. However, combined As and IFN induce the degradation of Tax, associated with an up-regulation of I kappa B-alpha resulting in a sharp decrease in RelA DNA binding nuclear factor (NF)-kappa B complexes because of the cytoplasmic retention of RelA. Taken the role of Tax in HTLV-I-induced transformation, its down-regulation probably accounts for cell death induction through inactivation of the NF-kappa B pathway. Such specific targeting of the viral oncoprotein by As-IFN treatment, reminiscent of As targeting of promyelocytic leukemia/retinoic acid receptor-alpha in acute promyelocytic leukemia, provides strong rational for combined As-IFN therapy in ATL patients. (Blood. 2000;96:2849-2855)


Assuntos
Apoptose/efeitos dos fármacos , Arsenicais/farmacologia , Transformação Celular Viral/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Regulação Viral da Expressão Gênica/efeitos dos fármacos , Produtos do Gene tax/fisiologia , Vírus Linfotrópico T Tipo 1 Humano/fisiologia , Proteínas I-kappa B , Interferon-alfa/farmacologia , Leucemia-Linfoma de Células T do Adulto/genética , NF-kappa B/metabolismo , Proteínas de Neoplasias/fisiologia , Óxidos/farmacologia , Ativação Transcricional/efeitos dos fármacos , Trióxido de Arsênio , Caspases/fisiologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Transformada , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Sinergismo Farmacológico , Ativação Enzimática , Humanos , Leucemia-Linfoma de Células T do Adulto/patologia , Ligases/metabolismo , Substâncias Macromoleculares , Inibidor de NF-kappaB alfa , Linfócitos T/metabolismo , Linfócitos T/virologia , Células Tumorais Cultivadas
19.
Eur J Haematol ; 65(3): 207-9, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11007058

RESUMO

The efficacy of interferon-alpha (IFN) was reported in three patients with congenital dyserythropoietic anaemia (CDA) type I. We describe two additional cases treated with IFN, which normalized the haemoglobin level in both patients with a dramatic decrease in the size of the spleen in one. Haemoglobin remained stable more than 6 months after discontinuation of treatment. IFN induced more than 50% decrease in the number of BFU-E in both patients' bone marrow cultures, suggesting an indirect effect of IFN on erythropoiesis in vivo. We conclude that a trial of IFN therapy should be considered in patients with CDA type I.


Assuntos
Anemia Diseritropoética Congênita/tratamento farmacológico , Interferon-alfa/uso terapêutico , Adulto , Células da Medula Óssea/patologia , Contagem de Células , Células Cultivadas , Células Precursoras Eritroides/patologia , Eritropoese , Feminino , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade
20.
Leukemia ; 14(4): 716-21, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10764160

RESUMO

The combination of the anti-viral agents, zidovudine (AZT) and interferon-alpha (IFN), is a potent treatment of HTLV-I-associated adult T cell leukemia/lymphoma (ATL). In this study we investigate the possible mechanism of action of this combination by examining several cellular parameters including cell proliferation, cell cycle distribution and apoptosis. The ATL-derived T cell lines HuT-102 and MT-2 served as models. HTLV-I negative T cell lines (CEM and Jurkat) were used as controls. No significant modification of cell growth was observed except at suprapharmacological doses of AZT and IFN. Moreover, these effects were less pronounced in HTLV-I-infected cell lines compared to control cell lines. AZT and IFN treatment did not induce any significant modification of the expression of bcl-2 and p53. Interestingly no in vitro cytotoxic effect of AZT/IFN combination was observed on fresh leukemic cells derived from an acute ATL patient at diagnosis despite achievement of in vivo complete remission using the same therapy. These results suggest that the therapeutic effect of AZT and IFN is not through a direct cytotoxic effect of these drugs on the leukemic cells.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Fatores Imunológicos/farmacologia , Interferon-alfa/farmacologia , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Zidovudina/farmacologia , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/análise , Sobrevivência Celular/efeitos dos fármacos , Terapia Combinada , DNA de Neoplasias/análise , Sinergismo Farmacológico , Feminino , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Humanos , Fatores Imunológicos/uso terapêutico , Interferon-alfa/uso terapêutico , Células Jurkat/efeitos dos fármacos , Leucemia-Linfoma de Células T do Adulto/patologia , Indução de Remissão , Células Tumorais Cultivadas/efeitos dos fármacos , Zidovudina/uso terapêutico
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