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3.
Otol Neurotol ; 42(5): e521-e529, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33629826

RESUMEN

OBJECTIVE: To investigate whether the long-term presence of a patulous Eustachian tube (PET) is associated with sensorineural hearing loss (SNHL). STUDY DESIGN: Retrospective chart review. SETTING: Tertiary referral center. PATIENTS: Ears (n = 100) were classified into two groups based on duration of PET symptom(s), i.e., Short (≤3 mo; n = 47 ears) and Long (≥48 mo; n = 53 ears). Contralateral ears without PET (n = 28 ears) were classified as the Contralateral group. MAIN OUTCOME MEASURES: We used ISO 7029 to calculate the hearing thresholds of an age- and sex-matched population at a given frequency. Hearing loss was defined as >25% of these calculated values. RESULTS: At 4 kHz, the Long PET group showed a higher prevalence of hearing loss (47%) at 4 kHz than did the Contralateral (21%) and Short PET (19%) groups (p = 0.0280 and 0.0043, respectively). Ears with breathing autophony or a sonotubometric low probe tone level showed a higher prevalence of hearing loss at 4 kHz than those without this symptom or with a high probe tone level (p = 0.0329 or 0.0103, respectively). At low frequencies, ≥89% of the ears in all groups showed mild hearing loss. CONCLUSION: Chronic PET was associated with SNHL at 4 kHz. PET patients showed low-frequency hearing loss regardless of disease duration. Further studies are needed to better understand the pathophysiology of SNHL in patients with PET.


Asunto(s)
Trompa Auditiva , Pérdida Auditiva Sensorineural , Otitis Media , Trompa Auditiva/diagnóstico por imagen , Audición , Pérdida Auditiva Sensorineural/diagnóstico por imagen , Pérdida Auditiva Sensorineural/epidemiología , Pérdida Auditiva Sensorineural/etiología , Humanos , Estudios Retrospectivos
4.
Pediatr Blood Cancer ; 65(6): e26982, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29384263

RESUMEN

PURPOSE: Pericardial effusion (PE) is a potentially life-threatening complication following hematopoietic stem cell transplantation (HCT). A higher incidence of early-onset PE, unrelated to graft-versus-host disease, before day 100 after HCT has been reported in pediatric patients, but the pathogenic mechanism is poorly understood. Aiming to determine the pathogenesis of early-onset PE in pediatric patients, we analyzed the cytokine concentration and cell population in the pericardial fluid of four pediatric patients with PE. METHODS: Between January 2009 and December 2015, four patients requiring pericardiocentesis for clinically significant PE were identified in 60 patients. We evaluated the interleukin-6 (IL-6), interferon-γ, IL-1ß, and tumor necrosis factor-α levels in PE. Two patients were available for analysis with intracellular cytokine flow cytometry and a chimerism assay. RESULTS: All patients showed the accumulation of pericardial macrophages and high concentrations of IL-6 in PE. Notably, the accumulated pericardial macrophages were CD163+ CD15+ CD14+ cells of host origin that produced IL-6. CONCLUSION: These IL-6-producing tissue-resident macrophages may be key players in the pathogenesis of early-onset PE.


Asunto(s)
Enfermedades Hematológicas/terapia , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Interleucina-6/metabolismo , Macrófagos/metabolismo , Derrame Pericárdico/patología , Edad de Inicio , Preescolar , Femenino , Humanos , Lactante , Macrófagos/patología , Masculino , Derrame Pericárdico/etiología , Derrame Pericárdico/metabolismo , Pronóstico , Factores de Riesgo
5.
Urology ; 97: 200-203, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27211929

RESUMEN

This report describes an unusual case of sarcomatoid carcinoma of the bladder in a 3-year-old girl. Although saving the patient's life is most essential, it is also essential to consider quality of life. The patient underwent neoadjuvant chemotherapy with gemcitabine and cisplatin for bladder preservation. The tumor considerably decreased in size. After 4 courses of chemotherapy, the patient underwent a partial cystectomy followed by postoperative irradiation with 2 courses of chemotherapy. Seventy months after the operation, she remains alive, showing complete remission with normal bladder function. Chemotherapy resulted in tumor shrinkage and allowed for bladder preservation.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma/terapia , Tratamientos Conservadores del Órgano , Neoplasias de la Vejiga Urinaria/terapia , Carcinoma/patología , Quimioterapia Adyuvante , Preescolar , Cisplatino/administración & dosificación , Cistectomía/métodos , Desoxicitidina/administración & dosificación , Desoxicitidina/análogos & derivados , Femenino , Humanos , Terapia Neoadyuvante , Radioterapia Adyuvante , Neoplasias de la Vejiga Urinaria/patología , Gemcitabina
6.
J Med Virol ; 86(2): 301-5, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24026669

RESUMEN

Epstein-Barr virus (EBV) has many strains; however, it remains unclear whether a causal relationship exists between different regions and viral genetic variants in healthy persons. This study was designed to examine the relationship between EBV strains in tonsils and adenoids and peripheral blood lymphocytes of the same individuals using different measurements of EBV strain polymorphism. This study examined whether EBV contains two or three copies of a tandem repeat sequence in the first intron of the BZLF-1 gene. The genotype of the virus from P3HR-1, designated Z*, yielded a 415-bp product, and this was distinguished from the smaller, 386-bp product obtained with the B95-8 virus, designated the Z genotype. Simultaneous sequence infections with Z and Z* genotypes were also detected in one of the tonsils examined, suggesting that more than one strain or variant of EBV genotype may be present in a specimen from the same subject. Co-infection with Z and Z* was recognized in two subjects, so variation of the EBV gene may be seen in at least two different strains of EBV. It was seen that Z and Z* strain-infected cells are constantly in flux through lymph nodes and/or the blood stream in healthy persons; therefore, these results indicated that EBV genome variants probably show no specific tissue distribution.


Asunto(s)
Infecciones por Virus de Epstein-Barr/virología , Variación Genética , Herpesvirus Humano 4/clasificación , Herpesvirus Humano 4/genética , Transactivadores/genética , Tonsila Faríngea/virología , Coinfección/virología , Voluntarios Sanos , Herpesvirus Humano 4/aislamiento & purificación , Humanos , Intrones , Linfocitos/virología , Tonsila Palatina/virología
8.
Chemotherapy ; 56(6): 453-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-21088397

RESUMEN

BACKGROUND: Cisplatin plus fluorouracil is widely used for the treatment of head and neck cancer. However, the cisplatin plus fluorouracil regimen necessitates hospitalization. Therefore, we planned to develop a new regimen that can be administered on an outpatient basis and performed a phase I study of S-1 + nedaplatin. METHODS: S-1 was given orally at a fixed dose for 14 days, and nedaplatin was administered intravenously on day 8 of S-1 administration. The dose of nedaplatin was increased in 10-mg/m(2) steps to find the maximum tolerated dose, depending on the appearance of dose-limiting toxicities. RESULTS: A total of 14 patients were registered. The maximum tolerated dose of nedaplatin was determined to be 90 mg/m(2). The main toxicities were neutropenia and thrombocytopenia. The response rate was 57.1%. CONCLUSION: The recommended dose of nedaplatin for a phase II study was determined to be 80 mg/m(2). We concluded that our regimen was well tolerated and that the response rate was acceptable.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Compuestos Organoplatinos/administración & dosificación , Ácido Oxónico/administración & dosificación , Tegafur/administración & dosificación , Anciano , Carcinoma/tratamiento farmacológico , Carcinoma de Células Escamosas , Cisplatino/administración & dosificación , Cisplatino/uso terapéutico , Progresión de la Enfermedad , Combinación de Medicamentos , Femenino , Fluorouracilo/administración & dosificación , Fluorouracilo/uso terapéutico , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Neoplasias de Células Escamosas/tratamiento farmacológico , Compuestos Organoplatinos/efectos adversos , Compuestos Organoplatinos/uso terapéutico , Ácido Oxónico/efectos adversos , Ácido Oxónico/uso terapéutico , Carcinoma de Células Escamosas de Cabeza y Cuello , Tegafur/efectos adversos , Tegafur/uso terapéutico
9.
Blood ; 2010 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-20071663

RESUMEN

Adult T-cell leukemia (ATL) is a T-cell malignancy etiologically associated with human T-cell leukemia virus type 1 (HTLV-1). Twist, a highly conserved basic helix-loop-helix transcription factor, is a newly identified oncogene. However, there are no reports on Twist expression in ATL. To define the role of Twist in leukemogenesis of ATL, we examined its expression in T-cell lines and PBMC. HTLV-1-infected T-cell lines and ATL cells expressed high levels of Twist compared with uninfected T-cell lines and normal PBMC. Immunohistochemistry showed immunostaining for Twist in ATL cells in ATL lymph nodes and skin lesions. Infection of normal PBMC with HTLV-1 induced Twist expression. Induction of the viral protein Tax in a human T-cell line led to upregulation of Twist. Tax-induced Twist expression involved the NF-kappaB and CREB signaling pathways. Twist augmented Tax-mediated HTLV-1 LTR and NF-kappaB activation. Short interfering RNA against Twist inhibited cell growth of HTLV-1-infected T-cell lines and downregulation of Twist expression in an HTLV-1-infected T-cell line inhibited the expression of Akt1, interleukin-2 receptor alpha chain, and Tax as well as the known target genes of Twist, YB-1 and Akt2. In conclusion, the results suggest that Tax-induced induction of Twist contributes to leukemogenesis of ATL.

10.
Oncol Rep ; 22(5): 1163-7, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19787235

RESUMEN

Preservation of the larynx is the most critical factor influencing quality of life in the treatment of head and neck cancer. This clinical study focuses on laryngeal function-preserving chemoradiotherapy for locally advanced hypopharyngeal and laryngeal cancer. Thirty-two resectable cases with histologically proven squamous cell carcinoma undergoing function-preserving therapy were examined. Induction chemotherapy comprised cisplatin and 5-fluorouracil, and another cycle of chemotherapy was performed for responders. Chemoradiotherapy comprised conventional irradiation and weekly chemotherapy (nedaplatin plus docetaxel). Non-responder patients were excluded from further chemotherapy and were changed to other surgical treatment. Three patients were non-responders for induction chemotherapy, and 29 patients were treated with chemoradiotherapy. Thus, 21 out of 29 patients obtained preserved laryngeal function. Initial larynx preservation rate with these treatment strategies was 93.8%. This study provides a new concept for laryngeal function-preserving treatment that should be considered for locally advanced laryngeal and hypopharyngeal cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/terapia , Neoplasias Hipofaríngeas/terapia , Neoplasias Laríngeas/terapia , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Cisplatino/administración & dosificación , Terapia Combinada , Femenino , Fluorouracilo/administración & dosificación , Humanos , Neoplasias Hipofaríngeas/tratamiento farmacológico , Neoplasias Hipofaríngeas/radioterapia , Neoplasias Laríngeas/tratamiento farmacológico , Neoplasias Laríngeas/radioterapia , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento
11.
Int J Cancer ; 124(11): 2607-15, 2009 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-19230025

RESUMEN

Human T-cell leukemia virus type 1 (HTLV-1) is the etiologic agent for adult T-cell leukemia (ATL). Aurora A, a mitotic checkpoint protein, is overexpressed in human cancer cells. The cell cycle-dependent turnover of Aurora A is regulated by E3 ubiquitin ligases such as checkpoint with fork head-associated and ring finger (CHFR). Here, we found overexpression of Aurora A protein in HTLV-1-infected T-cell lines and primary ATL cells. The expression of CHFR mRNA was reduced in these cells by abnormal methylation of CHFR promoter region. Knockdown of Aurora A using small interfering RNA suppressed the growth of HTLV-1-infected T-cell line. Transfection of Aurora A expression plasmid enhanced Tax-induced nuclear factor-kappaB (NF-kappaB) reporter activity. Transfection of CHFR expression plasmid into an HTLV-1-infected T-cell line reduced cell growth, Aurora A protein level and constitutive NF-kappaB reporter activity. Aurora kinase inhibitor suppressed the growth and survival of HTLV-1-infected T-cell lines and primary ATL cells. It also reduced constitutive NF-kappaB activity in an HTLV-1-infected T-cell line by reducing IkappaB kinase beta phosphorylation and the expression of antiapoptotic protein survivin. Our results suggested that loss of CHFR expression resulted to accumulation of Aurora A, which increased NF-kappaB activity. These findings highlight the critical role of Aurora A in HTLV-1-infected T cells, making this molecule a potentially suitable target for future therapies for ATL.


Asunto(s)
Proteínas de Ciclo Celular/genética , Virus Linfotrópico T Tipo 1 Humano/fisiología , Leucemia-Linfoma de Células T del Adulto/patología , FN-kappa B/metabolismo , Proteínas de Neoplasias/genética , Proteínas Serina-Treonina Quinasas/fisiología , Linfocitos T/virología , Apoptosis , Aurora Quinasas , Ciclo Celular , Línea Celular , Proliferación Celular , Supervivencia Celular , Metilación de ADN , Humanos , Leucemia-Linfoma de Células T del Adulto/enzimología , Proteínas de Unión a Poli-ADP-Ribosa , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Transducción de Señal , Linfocitos T/fisiología , Ubiquitina-Proteína Ligasas
12.
Biochem J ; 406(2): 317-23, 2007 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-17576198

RESUMEN

HTLV-1 (human T-cell leukaemia virus type 1) is the causative agent for ATL (adult T-cell leukaemia). HTLV-1 Tax can activate the PI3K (phosphoinositide 3-kinase)/Akt signalling pathway, which is responsible for survival of HTLV-1-infected T-cells. HIFs (hypoxia-inducible factors) are transcriptional regulators that play a central role in the response to hypoxia. Overexpression of HIF-1alpha in many cancers is associated with a poor response to treatment and increased patient mortality. Our objectives in the present study were to investigate whether HIF-1 was activated in HTLV-1-infected T-cells and to elucidate the molecular mechanisms of HIF-1 activation by focusing on the PI3K/Akt signalling pathway. We detected a potent pathway that activated HIF-1 in the HTLV-1-infected T-cells under a normal oxygen concentration. Enhanced HIF-1alpha protein expression and HIF-1 DNA-binding activity were exhibited in HTLV-1-infected T-cell lines. Knockdown of HIF-1alpha by siRNA (small interfering RNA) suppressed the growth and VEGF (vascular endothelial growth factor) expression of the HTLV-1-infected T-cell line. HIF-1 protein accumulation and transcriptional activity were enhanced by Tax, which was inhibited by dominant-negative Akt. Importantly, mutant forms of Tax that are defective in activation of the PI3K/Akt pathway failed to induce HIF-1 transcriptional activity. The PI3K inhibitor LY294002 suppressed HIF-1alpha protein expression, HIF-1 DNA-binding and HIF-1 transcriptional activity in HTLV-1-infected T-cell lines. In primary ATL cells, HIF-1alpha protein levels were strongly correlated with levels of phosphorylated Akt. The results of the present study suggest that PI3K/Akt activation induced by Tax leads to activation of HIF-1. As HIF-1 plays a major role in tumour progression, it may represent a molecular target for the development of novel ATL therapeutics.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano/fisiología , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Leucemia de Células T/metabolismo , Adulto , ADN/metabolismo , Activación Enzimática , Regulación Neoplásica de la Expresión Génica , Productos del Gen tax/farmacología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Leucemia de Células T/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosforilación , Unión Proteica , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Interferente Pequeño/genética , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas
13.
Int J Cancer ; 120(10): 2251-61, 2007 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-17278100

RESUMEN

ATL is a fatal malignancy of T lymphocytes caused by HTLV-I infection and remains incurable. Galectins are a family of animal lectins that function both extracellularly (by interacting with cell surface and extracellular matrix glycoproteins and glycolipids) and intracellularly (by interacting with cytoplasmic and nuclear proteins) to modulate signaling pathways. We found that protease-resistant galectin-9 by modification of its linker peptide, hG9NC(null), prevented cell growth of HTLV-I-infected T-cell lines and primary ATL cells. The suppression of cell growth was inhibited by lactose, but not by sucrose, indicating that beta-galactoside binding is essential for hG9NC(null)-induced cell growth suppression. hG9NC(null) induced cell cycle arrest by reducing the expression of cyclin D1, cyclin D2, cyclin B1, Cdk1, Cdk4, Cdk6, Cdc25C and c-Myc, and apoptosis by reducing the expression of XIAP, c-IAP2 and survivin. Most of these genes are regulated by NF-kappaB, which plays a critical role in oncogenesis by HTLV-I. hG9NC(null) suppressed IkappaBalpha phosphorylation, resulting in suppression of NF-kappaB. Most importantly, treatment with hG9NC(null) (6.7 mg/kg injected intraperitoneally every day) reduced tumor formation from an HTLV-I-infected T-cell line when these cells were inoculated subcutaneously into SCID mice. Our results suggest that hG9NC(null) could be a suitable agent for the management of ATL.


Asunto(s)
Apoptosis/efectos de los fármacos , Galectinas/farmacología , Infecciones por HTLV-I/tratamiento farmacológico , Virus Linfotrópico T Tipo 1 Humano/crecimiento & desarrollo , Leucemia-Linfoma de Células T del Adulto/terapia , Linfocitos T/patología , Linfocitos T/virología , Animales , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Ciclo Celular/fisiología , Línea Celular Tumoral , Femenino , Galactósidos/metabolismo , Galectinas/biosíntesis , Galectinas/genética , Inhibidores de Crecimiento/farmacología , Infecciones por HTLV-I/inmunología , Infecciones por HTLV-I/patología , Receptor 2 Celular del Virus de la Hepatitis A , Humanos , Leucemia-Linfoma de Células T del Adulto/inmunología , Leucemia-Linfoma de Células T del Adulto/patología , Proteínas de la Membrana , Ratones , Ratones SCID , FN-kappa B/genética , FN-kappa B/inmunología , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Receptores Virales/biosíntesis , Linfocitos T/inmunología , beta-Galactosidasa/metabolismo
14.
Int J Cancer ; 120(8): 1811-20, 2007 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-17230513

RESUMEN

The molecular chaperone Hsp90 is involved in the stabilization and conformational maturation of many signaling proteins that are deregulated in cancers. The geldanamycin derivative 17-AAG is currently tested in clinical trials and known to inhibit the function of Hsp90 and promote the proteasomal degradation of its misfolded client proteins. ATL is a fatal malignancy of T lymphocytes caused by HTLV-I infection and remains incurable. Since Hsp90 is overexpressed in HTLV-I-infected T-cell lines and primary ATL cells, we analyzed the effects of 17-AAG on cell survival, apoptosis and expression of signal transduction proteins. HTLV-I-infected T-cell lines and primary ATL cells were significantly more sensitive to 17-AAG in cell survival assays than normal PBMCs. 17-AAG induced the inhibition of cell cycle and apoptosis. These effects could be mediated by inactivation of NF-kappaB, AP-1 and PI3K/Akt pathways, as well as reduction of expression of proteins involved in the G1-S cell cycle transition and apoptosis. Proteasome inhibition interfered with 17-AAG-mediated signaling proteins depletion. Collectively, our results indicate that 17-AAG suppresses ATL cell survival through, at least in part, destabilization of several client proteins and suggest that 17-AAG is a potentially useful chemotherapeutic agent for ATL.


Asunto(s)
Apoptosis/efectos de los fármacos , Benzoquinonas/uso terapéutico , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Virus Linfotrópico T Tipo 1 Humano/efectos de los fármacos , Lactamas Macrocíclicas/uso terapéutico , Leucemia de Células T/tratamiento farmacológico , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , Linfocitos T/virología , Adulto , Ciclo Celular/efectos de los fármacos , Humanos , Leucemia de Células T/virología , Leucemia-Linfoma de Células T del Adulto/virología , FN-kappa B/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Linfocitos T/efectos de los fármacos , Factor de Transcripción AP-1/metabolismo , Células Tumorales Cultivadas
15.
Br J Haematol ; 136(3): 424-32, 2007 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17233845

RESUMEN

Anti-resorptive bisphosphonates are used for the treatment of hypercalcaemia and bone complications associated with malignancies and osteoporosis, but also have been shown to have anti-tumour effects in various cancers. Adult T-cell leukaemia (ATL) is a fatal T-cell malignancy caused by infection with human T-cell leukaemia virus type I (HTLV-I), and remains incurable. ATL is associated with osteolytic bone lesions and hypercalcaemia, both of which are major factors in the morbidity of ATL. Thus, the search for anti-ATL agents that have both anti-tumour and anti-resorptive activity is warranted. The bisphosphonate agent, incadronate, prevented cell growth of HTLV-I-infected T-cell lines and primary ATL cells, but not of non-infected T-cell lines or normal peripheral blood mononuclear cells. Incadronate induced S-phase cell cycle arrest and apoptosis in HTLV-I-infected T-cell lines, and treatment of these cells with substrates of the mevalonate pathway blocked the incadronate-mediated growth suppression. Incadronate also prevented the prenylation of Rap1A protein. These results demonstrated that incadronate-induced growth suppression occurs by interfering with the mevalonate pathway. Importantly, treatment with incadronate reduced tumour formation from an HTLV-I-infected T-cell line when these cells were inoculated subcutaneously into severe combined immunodeficient mice. These findings suggest that incadronate could be potentially useful for the treatment of ATL.


Asunto(s)
Antimetabolitos/uso terapéutico , Difosfonatos/uso terapéutico , Virus Linfotrópico T Tipo 1 Humano , Leucemia de Células T/tratamiento farmacológico , Ácido Mevalónico/metabolismo , Linfocitos T/metabolismo , Anciano , Animales , Antimetabolitos/farmacología , Apoptosis/efectos de los fármacos , Biomarcadores/análisis , Western Blotting/métodos , Caspasas/metabolismo , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Difosfonatos/farmacología , Femenino , Humanos , Proteínas Inhibidoras de la Apoptosis , Células Jurkat , Leucemia de Células T/metabolismo , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , Leucemia-Linfoma de Células T del Adulto/metabolismo , Masculino , Ratones , Ratones SCID , Proteínas Asociadas a Microtúbulos/análisis , Proteínas Asociadas a Microtúbulos/metabolismo , Persona de Mediana Edad , Proteínas de Neoplasias/análisis , Proteínas de Neoplasias/metabolismo , Trasplante de Neoplasias , Transducción de Señal/efectos de los fármacos , Survivin , Linfocitos T/virología
16.
Retrovirology ; 3: 22, 2006 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-16603085

RESUMEN

BACKGROUND: Human T-cell leukemia virus type 1 (HTLV-1), the etiologic agent for adult T-cell leukemia (ATL), induces cytokine-independent proliferation of T-cells, associated with the acquisition of constitutive activation of Janus kinases (Jak) and signal transducers and activators of transcription (Stat) proteins. Our purposes in this study were to determine whether activation of Jak-Stat pathway is responsible for the proliferation and survival of ATL cells, and to explore mechanisms by which inhibition of Jak-Stat pathway kills ATL cells. RESULTS: Constitutive activation of Stat3 and Stat5 was observed in HTLV-1-infected T-cell lines and primary ATL cells, but not in HTLV-1-negative T-cell lines. Using AG490, a Jak-specific inhibitor, we demonstrated that the activation of Stat3 and Stat5 was mediated by the constitutive phosphorylation of Jak proteins. AG490 inhibited the growth of HTLV-1-infected T-cell lines and primary ATL cells by inducing G1 cell-cycle arrest mediated by altering the expression of cyclin D2, Cdk4, p53, p21, Pim-1 and c-Myc, and by apoptosis mediated by the reduced expression of c-IAP2, XIAP, survivin and Bcl-2. Importantly, AG490 did not inhibit the growth of normal peripheral blood mononuclear cells. CONCLUSION: Our results indicate that activation of Jak-Stat pathway is responsible for the proliferation and survival of ATL cells. Inhibition of this pathway may provide a new approach for the treatment of ATL.


Asunto(s)
Virus Linfotrópico T Tipo 1 Humano/genética , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT5/metabolismo , Linfocitos T/virología , Secuencia de Bases , Línea Celular , Línea Celular Tumoral , Cartilla de ADN , Inhibidores Enzimáticos/farmacología , Humanos , Leucemia-Linfoma de Células T del Adulto , Fosforilación , Proteínas Tirosina Quinasas/metabolismo , Factores de Transcripción STAT/metabolismo , Factor de Transcripción STAT3/genética , Factor de Transcripción STAT5/genética , Transducción de Señal , Linfocitos T/enzimología , Tirfostinos/farmacología
17.
Cancer Sci ; 97(4): 322-7, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16630125

RESUMEN

The Akt signaling pathway is important for survival and growth of cancer cells. In the present paper we show that the Akt signaling pathway is constitutively activated in human T-cell leukemia virus type I (HTLV-I)-infected T-cell lines and in primary adult T-cell leukemia (ATL) cells. Curcumin, a natural compound present in turmeric, has been studied vigorously as a potent chemopreventive agent for cancer therapy because of its inhibitory effect on proliferation and induction of apoptosis in several tumor cell lines. We investigated the effect of curcumin on Akt activity in HTLV-I-infected T-cell lines and primary ATL cells. Phosphorylated PDK1 is an activator of Akt by phosphorylating Akt. Curcumin reduced phosphorylation of PDK1 and inhibited constitutive activation of Akt. Curcumin activated glycogen synthase kinase (GSK)-3beta, a downstream target of Akt kinase, by inhibiting phosphorylation of this protein. Curcumin reduced the expression of cell cycle regulators, cyclin D1 and c-Myc proteins, which are both degraded by activated GSK-3beta. Our results suggest that activation of the Akt signaling pathway plays an important role in ATL cell survival, and that curcumin may have anti-ATL properties mediated, at least in part, by inhibiting Akt activity. We propose that Akt-targeting agents could be useful for the treatment of ATL. In this regard, curcumin is a potentially promising compound for the treatment of ATL.


Asunto(s)
Antineoplásicos/farmacología , Supervivencia Celular/efectos de los fármacos , Curcumina/farmacología , Virus Linfotrópico T Tipo 1 Humano/efectos de los fármacos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal , Linfocitos T/virología , Glucógeno Sintasa Quinasa 3/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Humanos , Fosforilación/efectos de los fármacos , Linfocitos T/efectos de los fármacos , Células Tumorales Cultivadas/virología
18.
Mol Cancer Ther ; 5(3): 704-12, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16546985

RESUMEN

Adult T-cell leukemia (ATL) is caused by human T-cell leukemia virus type I (HTLV-I) and remains incurable. NIK-333, a novel synthetic retinoid, prevents the recurrence of human hepatoma after surgical resection of primary tumors. We explored the effects of NIK-333 on HTLV-I-infected T-cell lines and ATL cells. NIK-333 inhibited cell proliferation, induced G1 arrest, and resulted in massive apoptosis in all tested HTLV-I-infected T-cell lines and ATL cells, whereas little effect was observed on normal peripheral blood mononuclear cells. NIK-333 treatment decreases the levels of cyclin D1, cyclin D2, cIAP2, and XIAP proteins. Further analysis showed that NIK-333 inactivated nuclear factor-kappaB in HTLV-I-infected T-cell lines. In animal studies, treatment with NIK-333 (100 mg/kg given orally every other day) produced partial inhibition of growth of tumors of a HTLV-I-infected T-cell line transplanted s.c. in severe combined immunodeficient mice. Our results indicate that NIK-333 is a potentially useful therapeutic agent for patients with ATL.


Asunto(s)
Infecciones por HTLV-I/tratamiento farmacológico , Virus Linfotrópico T Tipo 1 Humano , Leucemia de Células T/tratamiento farmacológico , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , FN-kappa B/antagonistas & inhibidores , Retinoides/uso terapéutico , Animales , Apoptosis , Línea Celular Transformada , Línea Celular Tumoral , Ciclina D1/metabolismo , Ciclina D2 , Ciclinas/metabolismo , Regulación hacia Abajo , Femenino , Infecciones por HTLV-I/virología , Humanos , Proteínas Inhibidoras de la Apoptosis/metabolismo , Leucemia de Células T/virología , Leucemia-Linfoma de Células T del Adulto/virología , Ratones , Ratones Endogámicos , Transducción de Señal , Linfocitos T/virología , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo
19.
Br J Haematol ; 132(3): 293-302, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16409294

RESUMEN

CCL20 is expected to play a crucial role in the initiation of immune responses and tumour growth. However, expression of CCL20 in Epstein-Barr virus (EBV)-associated diseases has not been studied. We examined the contribution of EBV infection and EBV-encoded latent membrane protein (LMP)-1 to CCL20 expression. EBV infection and LMP-1 induced CCL20 mRNA expression in the EBV-negative Burkitt lymphoma (BL) cell lines and the embryonic kidney cell line. Histone deacetylase inhibitor-stimulated endogenous LMP-1 also induced CCL20 expression in an EBV-positive BL cell line. Analysis of the CCL20 promoter showed that it was activated by LMP-1 C-terminal activation region (CTAR)-1 and CTAR-2. Co-expression of IkappaB alpha, IkappaB beta, IkappaB kinase (IKK)alpha, IKKbeta, IKKgamma, nuclear factor (NF)-kappaB-inducing kinase and tumour necrosis factor receptor-associated factor 2 dominant-negative constructs with LMP-1 inhibited the activation of the CCL20 promoter by LMP-1, suggesting that LMP-1 induces CCL20 via NF-kappaB signalling. The requirement for the NF-kappaB-binding site in the CCL20 promoter in LMP-1 responsiveness was established. Our results indicate that activation of the NF-kappaB pathway by LMP-1 is required for the activation of CCL20 expression.


Asunto(s)
Quimiocinas CC/análisis , Infecciones por Virus de Epstein-Barr/genética , Proteínas Inflamatorias de Macrófagos/análisis , Proteínas de la Matriz Viral/genética , Linfoma de Burkitt/genética , Linfoma de Burkitt/inmunología , Línea Celular , Quimiocina CCL20 , Infecciones por Virus de Epstein-Barr/inmunología , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/inmunología , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/inmunología , Histona Desacetilasa 1 , Histona Desacetilasas/inmunología , Humanos , Riñón/inmunología , FN-kappa B/genética , FN-kappa B/inmunología , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/inmunología , Regiones Promotoras Genéticas/genética , Regiones Promotoras Genéticas/inmunología , ARN Mensajero/análisis , Transducción de Señal/genética , Transducción de Señal/inmunología , Activación Transcripcional/genética , Activación Transcripcional/inmunología , Regulación hacia Arriba/genética , Regulación hacia Arriba/inmunología , Proteínas de la Matriz Viral/inmunología
20.
Int J Cancer ; 118(3): 765-72, 2006 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-16106398

RESUMEN

Adult T-cell leukemia (ATL) is a fatal malignancy of T lymphocytes caused by infection with human T-cell leukemia virus type I (HTLV-I) and remains incurable. Curcumin (diferuloylmethane), the major pigment of the spice turmeric, can be potentially effective by promoting cell apoptosis. Here we examined whether curcumin is effective in the treatment of ATL. Curcumin prevented cell growth of HTLV-I-infected T-cell lines and primary ATL cells but not of normal peripheral blood mononuclear cells. Curcumin induced cell cycle arrest by reducing the expression of cyclin D1, Cdk1 and Cdc25C and apoptosis by reducing the expression of XIAP and survivin. Most of these genes are known to be regulated by NF-kappaB, which plays a critical role in oncogenesis by HTLV-I. Curcumin suppressed constitutive active NF-kappaB of HTLV-I-infected T-cell lines and primary ATL cells by inhibiting phosphorylation of IkappaBalpha. Curcumin also inhibited Tax-induced NF-kappaB transcriptional activity. However, curcumin-induced suppression of cell growth did not correlate with Tax expression level. Curcumin inhibited the growth of HTLV-I-infected T-cell tumors implanted subcutaneously in SCID mice. Our results indicate that curcumin has tumor-suppressive activity against ATL.


Asunto(s)
Antineoplásicos/uso terapéutico , Proliferación Celular/efectos de los fármacos , Curcumina/uso terapéutico , Leucemia de Células T/tratamiento farmacológico , Leucemia-Linfoma de Células T del Adulto/tratamiento farmacológico , FN-kappa B/metabolismo , Linfocitos T , Adulto , Animales , Apoptosis/efectos de los fármacos , Proteína Quinasa CDC2/metabolismo , Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/metabolismo , Ciclina D1/metabolismo , Femenino , Productos del Gen tax/farmacología , Virus Linfotrópico T Tipo 1 Humano/efectos de los fármacos , Humanos , Proteínas Inhibidoras de la Apoptosis , Ratones , Ratones Endogámicos ICR , Ratones SCID , Proteínas Asociadas a Microtúbulos/metabolismo , FN-kappa B/antagonistas & inhibidores , FN-kappa B/genética , Proteínas de Neoplasias/metabolismo , Survivin , Linfocitos T/efectos de los fármacos , Linfocitos T/virología , Células Tumorales Cultivadas , Proteína Inhibidora de la Apoptosis Ligada a X/metabolismo , Fosfatasas cdc25/metabolismo
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