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1.
Blood ; 127(26): 3387-97, 2016 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-27121473

RESUMEN

Sézary syndrome (SS) is a leukemic variant of cutaneous T-cell lymphoma (CTCL) and represents an ideal model for study of T-cell transformation. We describe whole-exome and single-nucleotide polymorphism array-based copy number analyses of CD4(+) tumor cells from untreated patients at diagnosis and targeted resequencing of 101 SS cases. A total of 824 somatic nonsynonymous gene variants were identified including indels, stop-gain/loss, splice variants, and recurrent gene variants indicative of considerable molecular heterogeneity. Driver genes identified using MutSigCV include POT1, which has not been previously reported in CTCL; and TP53 and DNMT3A, which were also identified consistent with previous reports. Mutations in PLCG1 were detected in 11% of tumors including novel variants not previously described in SS. This study is also the first to show BRCA2 defects in a significant proportion (14%) of SS tumors. Aberrations in PRKCQ were found to occur in 20% of tumors highlighting selection for activation of T-cell receptor/NF-κB signaling. A complex but consistent pattern of copy number variants (CNVs) was detected and many CNVs involved genes identified as putative drivers. Frequent defects involving the POT1 and ATM genes responsible for telomere maintenance were detected and may contribute to genomic instability in SS. Genomic aberrations identified were enriched for genes implicated in cell survival and fate, specifically PDGFR, ERK, JAK STAT, MAPK, and TCR/NF-κB signaling; epigenetic regulation (DNMT3A, ASLX3, TET1-3); and homologous recombination (RAD51C, BRCA2, POLD1). This study now provides the basis for a detailed functional analysis of malignant transformation of mature T cells and improved patient stratification and treatment.


Asunto(s)
Reparación del ADN , Genoma Humano , Inestabilidad Genómica , Síndrome de Sézary/genética , Supervivencia Celular/genética , Epigénesis Genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Síndrome de Sézary/metabolismo , Transducción de Señal/genética
2.
Blood ; 116(7): 1105-13, 2010 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-20448109

RESUMEN

MicroRNAs are commonly aberrantly expressed in many cancers. Very little is known of their role in T-cell lymphoma, however. We therefore elucidated the complete miRNome of purified T cells from 21 patients diagnosed with Sézary Syndrome (SzS), a rare aggressive primary cutaneous T-cell (CD4(+)) lymphoma. Unsupervised cluster analysis of microarray data revealed that the microRNA expression profile was distinct from CD4(+) T-cell controls and B-cell lymphomas. The majority (104 of 114) of SzS-associated microRNAs (P < .05) were down-regulated and their expression pattern was largely consistent with previously reported genomic copy number abnormalities and were found to be highly enriched (P < .001) for aberrantly expressed target genes. Levels of miR-223 distinguished SzS samples (n = 32) from healthy controls (n = 19) and patients with mycosis fungoides (n = 11) in more than 90% of samples. Furthermore, we demonstrate that the down-regulation of intronically encoded miR-342 plays a role in the pathogenesis of SzS by inhibiting apoptosis, and describe a novel mechanism of regulation for this microRNA via binding of miR-199a* to its host gene. We also provide the first in vivo evidence for down-regulation of the miR-17-92 cluster in malignancy and demonstrate that ectopic miR-17-5p expression increases apoptosis and decreases cell proliferation in SzS cells.


Asunto(s)
Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/fisiología , Síndrome de Sézary/genética , Apoptosis , Western Blotting , Proliferación Celular , Perfilación de la Expresión Génica , Humanos , Luciferasas/metabolismo , Linfoma de Células B/sangre , Linfoma de Células B/diagnóstico , Linfoma de Células B/genética , MicroARNs/genética , Micosis Fungoide/sangre , Micosis Fungoide/diagnóstico , Micosis Fungoide/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Pronóstico , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Síndrome de Sézary/sangre , Síndrome de Sézary/diagnóstico , Linfocitos T/metabolismo
3.
Front Oncol ; 12: 1043254, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36505788

RESUMEN

Cutaneous T-cell lymphomas (CTCL) are a heterogeneous group of non-Hodgkin's lymphomas (NHL) characterised by the clonal proliferation of malignant, skin homing T-cells. Recent advances have been made in understanding the molecular pathogenesis of CTCL. Multiple deep sequencing studies have revealed a complex genomic landscape with large numbers of novel single nucleotide variants (SNVs) and copy number variations (CNVs). Commonly perturbed genes include those involved in T-cell receptor signalling, T-cell proliferation, differentiation and survival, epigenetic regulators as well as genes involved in genome maintenance and DNA repair. In addition, studies in CTCL have identified a dominant UV mutational signature in contrast to systemic T-cell lymphomas and this likely contributes to the high tumour mutational burden. As current treatment options for advanced stages of CTCL are associated with short-lived responses, targeting these deregulated pathways could provide novel therapeutic approaches for patients. In this review article we summarise the key pathways disrupted in CTCL and discuss the potential therapeutic implications of these findings.

4.
Sci Rep ; 11(1): 3962, 2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33597573

RESUMEN

T-cell non-Hodgkin's lymphomas develop following transformation of tissue resident T-cells. We performed a meta-analysis of whole exome sequencing data from 403 patients with eight subtypes of T-cell non-Hodgkin's lymphoma to identify mutational signatures and associated recurrent gene mutations. Signature 1, indicative of age-related deamination, was prevalent across all T-cell lymphomas, reflecting the derivation of these malignancies from memory T-cells. Adult T-cell leukemia-lymphoma was specifically associated with signature 17, which was found to correlate with the IRF4 K59R mutation that is exclusive to Adult T-cell leukemia-lymphoma. Signature 7, implicating UV exposure was uniquely identified in cutaneous T-cell lymphoma (CTCL), contributing 52% of the mutational burden in mycosis fungoides and 23% in Sezary syndrome. Importantly this UV signature was observed in CD4 + T-cells isolated from the blood of Sezary syndrome patients suggesting extensive re-circulation of these T-cells through skin and blood. Analysis of non-Hodgkin's T-cell lymphoma cases submitted to the national 100,000 WGS project confirmed that signature 7 was only identified in CTCL strongly implicating UV radiation in the pathogenesis of cutaneous T-cell lymphoma.


Asunto(s)
Linfoma Cutáneo de Células T/etiología , Linfoma Cutáneo de Células T/genética , Rayos Ultravioleta/efectos adversos , Linfocitos T CD4-Positivos/metabolismo , Bases de Datos Genéticas , Humanos , Factores Reguladores del Interferón , Linfoma de Células T/etiología , Linfoma de Células T/genética , Linfoma de Células T/metabolismo , Linfoma de Células T/patología , Linfoma Cutáneo de Células T/patología , Mutación/genética , Síndrome de Sézary/sangre , Neoplasias Cutáneas/patología
5.
J Invest Dermatol ; 140(2): 380-389.e4, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31376383

RESUMEN

Phospholipase C Gamma 1 (PLCG1) is frequently mutated in primary cutaneous T-cell lymphoma (CTCL). This study functionally interrogated nine PLCG1 mutations (p.R48W, p.S312L, p.D342N, p.S345F, p.S520F, p.R1158H, p.E1163K, p.D1165H, and the in-frame indel p.VYEEDM1161V) identified in Sézary Syndrome, the leukemic variant of CTCL. The mutations were demonstrated in diagnostic samples and persisted in multiple tumor compartments over time, except in patients who achieved a complete clinical remission. In basal conditions, the majority of the mutations confer PLCγ1 gain-of-function activity through increased inositol phosphate production and the downstream activation of NFκB, AP-1, and NFAT transcriptional activity. Phosphorylation of the p.Y783 residue is essential for the proximal activity of wild-type PLCγ1, but we provide evidence that activating mutations do not require p.Y783 phosphorylation to stimulate downstream NFκB, NFAT, and AP-1 transcriptional activity. Finally, the gain-of-function effects associated with the p.VYEEDM1161V indel suggest that the C2 domain may have a role in regulating PLCγ1 activity. These data provide compelling evidence to support the development of therapeutic strategies targeting mutant PLCγ1.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Fosfolipasa C gamma/genética , Síndrome de Sézary/genética , Transducción de Señal/genética , Neoplasias Cutáneas/genética , Animales , Células COS , Chlorocebus aethiops , Mutación con Ganancia de Función , Células HEK293 , Humanos , Mutación INDEL , Células Jurkat , Modelos Moleculares , Mutagénesis Sitio-Dirigida , FN-kappa B/metabolismo , Factores de Transcripción NFATC/metabolismo , Fosforilación/genética , Dominios Proteicos/genética , Síndrome de Sézary/patología , Neoplasias Cutáneas/patología , Factor de Transcripción AP-1/metabolismo
6.
J Invest Dermatol ; 139(9): 1975-1984.e2, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30910759

RESUMEN

FK228 (romidepsin) and suberoylanilide hydroxamic acid (vorinostat) are histone deacetylase inhibitors (HDACi) approved by the US Food and Drug Administration for cutaneous T-cell lymphoma (CTCL), including the leukemic subtype Sézary syndrome. This study investigates RAD23B and STAT3 gene perturbations in a large cohort of primary Sézary cells and the effect of FK228 treatment on tyrosine phosphorylation of STAT3 (pYSTAT3) and RAD23B expression. We report RAD23B copy number variation in 10% (12/119, P ≤ 0.01) of SS patients, associated with reduced mRNA expression (P = 0.04). RAD23B knockdown in a CTCL cell line led to a reduction in FK228-induced apoptosis. Histone deacetylase inhibitor treatment significantly reduced pYSTAT3 in primary Sézary cells and was partially mediated by RAD23B. A distinct pattern of RAD23B-pYSTAT3 co-expression in primary Sézary cells was detected. Critically, Sézary cells harboring the common STAT3 Y640F variant were less sensitive to FK228-induced apoptosis and exogenous expression of STAT3 Y640F, and D661Y conferred partial resistance to STAT3 transcriptional inhibition by FK228 (P ≤ 0.0024). These findings suggest that RAD23B and STAT3 gene perturbations could reduce sensitivity to histone deacetylase inhibitors in SS patients.


Asunto(s)
Enzimas Reparadoras del ADN/genética , Proteínas de Unión al ADN/genética , Depsipéptidos/farmacología , Resistencia a Antineoplásicos/genética , Inhibidores de Histona Desacetilasas/farmacología , Factor de Transcripción STAT3/genética , Síndrome de Sézary/genética , Neoplasias Cutáneas/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Apoptosis/genética , Linfocitos T CD4-Positivos , Variaciones en el Número de Copia de ADN , Enzimas Reparadoras del ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Depsipéptidos/uso terapéutico , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Inhibidores de Histona Desacetilasas/uso terapéutico , Humanos , Células Neoplásicas Circulantes , Fosforilación/efectos de los fármacos , Polimorfismo de Nucleótido Simple , Cultivo Primario de Células , Factor de Transcripción STAT3/metabolismo , Síndrome de Sézary/sangre , Síndrome de Sézary/tratamiento farmacológico , Síndrome de Sézary/patología , Piel/citología , Piel/patología , Neoplasias Cutáneas/sangre , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Células Tumorales Cultivadas , Tirosina/metabolismo
7.
J Cutan Pathol ; 35(8): 770-3, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18422691

RESUMEN

Genital herpes simplex virus (HSV) infection is usually a straightforward clinical diagnosis, rarely requiring histological confirmation. We report two cases of immunosuppressed patients in which the clinical and pathological features were initially suspicious for cutaneous lymphoma with a T-cell clone detected in one case. A diagnosis of HSV infection was eventually made on the basis of histological features and confirmed with immunohistochemistry.


Asunto(s)
Herpes Genital/patología , Huésped Inmunocomprometido , Linfoma Cutáneo de Células T/patología , Adulto , Diagnóstico Diferencial , Herpes Genital/inmunología , Humanos , Inmunohistoquímica/métodos , Linfoma Cutáneo de Células T/inmunología , Masculino
8.
J Cutan Pathol ; 35(10): 899-910, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18494816

RESUMEN

Activator protein 1 (AP-1) consists of a group of transcription factors including the JUN and FOS family proteins with diverse biological functions. This study assessed the genomic and expression status of the AP-1 transcription factors in primary cutaneous T-cell lymphoma (CTCL) by using immunohistochemistry (IHC), Affymetrix expression microarray, real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and fluorescent in situ hybridization (FISH). IHC showed JUNB protein expression in tumor cells from 17 of 33 cases of Sezary syndrome (SS) and JUND protein expression in 16 of 23 mycosis fungoides cases. There was no correlation between JUNB and CD30 expression. However, 7 of 12 JUNB-positive SS cases expressed both phosphorylated and total extracellular signal-regulated kinase (ERK) 1/2 mitogen-activated protein kinase (MAPK) proteins. Expression microarray showed over threefold increased expression of JUNB in three of six SS patients and similar findings were also noted after re-analysis of previously published data. Real-time RT-PCR confirmed the overexpression of JUNB in four SS cases and of JUND in three of four cases. FISH showed increased JUNB copy number in four of seven SS cases. These findings suggest that deregulation of AP-1 expression in CTCL is the result of aberrant expression of JUNB and possible JUND resulting from genomic amplification and constitutive activation of ERK1/2 MAPK in this type of lymphoma.


Asunto(s)
Micosis Fungoide/metabolismo , Proteínas Proto-Oncogénicas c-jun/biosíntesis , Síndrome de Sézary/metabolismo , Neoplasias Cutáneas/metabolismo , Factor de Transcripción AP-1/biosíntesis , Expresión Génica , Perfilación de la Expresión Génica , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Micosis Fungoide/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteínas Proto-Oncogénicas c-jun/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Síndrome de Sézary/genética , Neoplasias Cutáneas/genética , Factor de Transcripción AP-1/genética
9.
Am J Dermatopathol ; 30(5): 462-5, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18806490

RESUMEN

Granulomatous slack skin disease (GSS) is a very rare form of T-cell lymphoma, with only 52 cases reported in the literature. In the recent World Health Organization-European Organization for Research and Treatment of Cancer consensus classification GSS is considered to be a variant of mycosis fungoides. We describe a patient with GSS and histologic evidence of necrobiosis, which has not been previously reported.


Asunto(s)
Linfoma Cutáneo de Células T/complicaciones , Linfoma Cutáneo de Células T/diagnóstico , Trastornos Necrobióticos/complicaciones , Trastornos Necrobióticos/diagnóstico , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/diagnóstico , Biopsia , Linfocitos T CD4-Positivos/metabolismo , Linfocitos T CD4-Positivos/patología , Humanos , Antígenos Comunes de Leucocito/metabolismo , Linfoma Cutáneo de Células T/patología , Masculino , Persona de Mediana Edad , Trastornos Necrobióticos/patología , Neoplasias Cutáneas/patología , Organización Mundial de la Salud
10.
Cancer Treat Rev ; 33(2): 146-60, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17275192

RESUMEN

Primary cutaneous T-cell lymphomas are a heterogenous group of non-Hodgkin lymphomas. The characteristic clinicopathologic and immunophenotypic features and prognoses of the various cutaneous lymphomas have been recently described by the World Health Organization and European Organization for Research and Treatment of Cancer. Cutaneous T-cell lymphoma variants include mycosis fungoides and Sezary syndrome, which are generally associated, respectively, with indolent and aggressive clinical courses and are the subject of this review. Currently utilized treatments for cutaneous T-cell lymphoma include skin-directed therapies (topical agents such as corticosteroids, mechlorethamine, carmustine, and retinoids, phototherapy, superficial radiotherapy, and total skin electron beam therapy), systemic therapies (photophoresis, retinoids, denileukin diftitox, interferons, and chemotherapy), and stem cell transplantation (autologous and allogeneic). This review will describe recent advances in our understanding of the biology (immunologic, cytogenetic, and genetic) of cutaneous T-cell lymphomas and discuss the efficacy and tolerability of the current therapeutic options for cutaneous T-cell lymphomas. Disease progression in over 20% of patients with early stages of disease and the current lack of a definitive treatment which produces durable responses in advanced stages of disease indicates a critical unmet need in CTCL. New insights into the molecular and immunologic changes associated with cutaneous T-cell lymphomas should ultimately lead to the identification of novel therapeutic targets and the development of improved therapeutic options for patients with these malignancies.


Asunto(s)
Micosis Fungoide/terapia , Síndrome de Sézary/terapia , Neoplasias Cutáneas/terapia , Humanos , Resultado del Tratamiento
11.
J Invest Dermatol ; 126(10): 2217-23, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16741512

RESUMEN

Mycosis fungoides and its leukemic variant, Sezary syndrome, are the most common primary cutaneous T-cell lymphomas (CTCLs). In an ex vivo study, we investigated the percentage, phenotype, and suppressive function of CD4+CD25+ regulatory T cells (Tregs) from peripheral blood of CTCL patients. The percentage of Tregs did not differ significantly between patients and controls. Functional assays demonstrated a dichotomy in Treg function: in four out of 10 patients CD4+CD25+ T cells were incapable of suppressing autologous CD4+CD25- T-cell proliferation, whereas suppressive function was intact in the other six patients. Suppressive activity of Tregs inversely correlated with the peripheral blood tumor burden. T-plastin gene expression, used as a Sezary cell marker, confirmed that Sezary cells were heterogeneous for CD25 expression. Mixed lymphocyte reactions demonstrated that CD4+CD25- T cells from patients who lacked functional Tregs were susceptible to suppression by Tregs from healthy controls, and had not become suppressive themselves. Furthermore, we found reduced expression of Foxp3 in the CD4+CD25+ Tregs of these patients relative to the other six CTCL patients and controls. Our findings thus indicate a dysfunction of peripheral Tregs in certain CTCL patients, which correlates with tumor burden.


Asunto(s)
Factores de Transcripción Forkhead/análisis , Linfoma Cutáneo de Células T/inmunología , Neoplasias Cutáneas/inmunología , Linfocitos T Reguladores/fisiología , Anciano , Antígenos CD , Antígenos de Diferenciación/genética , Antígeno CTLA-4 , Femenino , Factores de Transcripción Forkhead/genética , Humanos , Linfoma Cutáneo de Células T/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , ARN Mensajero/análisis , Neoplasias Cutáneas/patología
12.
J Invest Dermatol ; 126(8): 1893-9, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16741518

RESUMEN

Molecular characterization of T-cell receptor junctional region sequences in cutaneous T-cell lymphoma had not been previously reported. We have examined in detail the features of the T-cell receptor beta (TCRB) gene rearrangements in 20 individuals with well-defined stages of cutaneous T-cell lymphoma (CTCL) comprising 10 cases with early-stage mycosis fungoides (MF) and 10 cases with late-stage MF or Sezary syndrome. Using BIOMED-2 PCR primers, we detected a high frequency of clonally rearranged TCR gamma and TCRB genes (17/20 and 15/20 cases, respectively). We carried out sequencing analysis of each complete clonal variable (V)beta-diversity (D)beta-joining(J)beta fingerprint generated by PCR amplification, and determined the primary structure of the Vbeta-Dbeta-Jbeta junctional regions. We observed considerable diversity in the T-cell receptor Vbeta gene usage and complementarity-determining region 3 loops. Although we found that TCRB gene usage in CTCL and normal individuals share common features, our analysis also revealed preferential usage of Jbeta1 genes in all cases with advanced stages of disease.


Asunto(s)
Reordenamiento Génico de la Cadena beta de los Receptores de Antígenos de los Linfocitos T/genética , Genes Codificadores de la Cadena beta de los Receptores de Linfocito T/genética , Linfoma de Células T/genética , Neoplasias Cutáneas/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Linfoma de Células T/inmunología , Micosis Fungoide/genética , Micosis Fungoide/inmunología , Análisis de Secuencia de ADN , Síndrome de Sézary/genética , Síndrome de Sézary/inmunología , Neoplasias Cutáneas/inmunología
13.
J Invest Dermatol ; 126(6): 1388-95, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-16614728

RESUMEN

Upregulation of cyclin D1/B-cell leukemia/lymphoma 1 (CCND1/BCL1) is present in most mantle cell lymphomas with the t(11;14)(q13;q32) translocation. However, little is known about the abnormalities of CCND1 and its regulator RB1 in primary cutaneous T-cell lymphomas (CTCL). We analyzed CCND and RB status in CTCL using fluorescent in situ hybridization (FISH), immunohistochemistry (IHC), and Affymetrix expression microarray. FISH revealed loss of CCND1/BCL1 in five of nine Sézary syndrome (SS) cases but gain in two cases, and RB1 loss in four of seven SS cases. IHC showed absent CCND1/BCL1 expression in 18 of 30 SS, 10 of 23 mycosis fungoides (MF), and three of 10 primary cutaneous CD30+ anaplastic large-cell lymphoma (C-ALCL). Increased CCND1/BCL1 expression was seen in nine MF, seven C-ALCL, and six SS cases. Absent RB1 expression was detected in 8 of 12 MF and 7 of 9 SS cases, and raised RB1 expression in 7 of 8 C-ALCL. Affymetrix revealed increased gene expression of CCND2 in four of eight CTCL cases, CCND3 in three cases, and CDKN2C in two cases with a normal expression of CCND1 and RB1. These findings suggest heterogeneous abnormalities of CCND and RB in CTCL, in which dysregulated CCND and RB1 may lead to impaired cell cycle control.


Asunto(s)
Deleción Cromosómica , Ciclina D1/genética , Regulación Neoplásica de la Expresión Génica , Linfoma Cutáneo de Células T/genética , Proteína de Retinoblastoma/genética , Neoplasias Cutáneas/genética , Núcleo Celular/química , Núcleo Celular/genética , Aberraciones Cromosómicas , Cromosomas Humanos Par 11/genética , Cromosomas Humanos Par 14/genética , Ciclina D1/análisis , Femenino , Humanos , Hibridación Fluorescente in Situ , Linfoma Anaplásico de Células Grandes/química , Linfoma Anaplásico de Células Grandes/genética , Linfoma Cutáneo de Células T/química , Masculino , Micosis Fungoide/química , Micosis Fungoide/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Proteína de Retinoblastoma/análisis , Síndrome de Sézary/química , Síndrome de Sézary/genética , Neoplasias Cutáneas/química , Regulación hacia Arriba
14.
Cancer Res ; 63(24): 9048-54, 2003 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-14695224

RESUMEN

Sezary Syndrome (SzS) is a leukemic variant of cutaneous T-cell lymphoma characterized by the accumulation of clonal neoplastic CD4+ T cells. The signal transducers and activators of transcription (STAT) family members, Stat5a and Stat5b, play an important role in regulating T-cell activation. Recent studies have shown that inappropriate activation of STATs occurs frequently in a wide variety of human cancers. Here we examine the functional status of Stat5 proteins in SzS as compared with healthy donors. Western blotting demonstrates that in cytoplasmic extracts of unstimulated T cells from healthy controls two isoforms of Stat5, full-length and a COOH-terminal truncated isoform, termed Stat5(t), are present. However, bandshift assays demonstrate that only Stat5(t) translocates to the nucleus and binds DNA on IL-2 stimulation. In contrast, preactivated T cells express only full-length Stat5, which is functionally activated on IL-2 stimulation. Analysis of Stat5 protein isoforms from five of five SzS patients revealed predominant aberrant expression of Stat5(t) in preactivated peripheral blood mononuclear cell. Furthermore, patients showed preferential IL-2-induced DNA binding of Stat5(t). Consistent with the inappropriate activation of Stat5(t) in SzS patients, real-time PCR revealed that IL-2-induced mRNA expression of the Stat5 target genes, Bcl-2, PIM-1, and CISH were markedly reduced. These data indicate that functional Stat5 isoform expression is regulated by T-cell activation status and that dysregulated expression of Stat5(t) in malignant T cells in SzS can suppress Stat5-dependent gene expression. Thus, aberrant expression of Stat5(t) may be one mechanism that contributes to the cellular transformation of T cells in this disease.


Asunto(s)
Proteínas de Unión al ADN/biosíntesis , Regulación Neoplásica de la Expresión Génica , Interleucina-2/farmacología , Proteínas de la Leche , Síndrome de Sézary/sangre , Transactivadores/biosíntesis , Adulto , Núcleo Celular/metabolismo , ADN de Neoplasias/metabolismo , Proteínas de Unión al ADN/sangre , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Leucocitos Mononucleares/metabolismo , Leucocitos Mononucleares/fisiología , Factor de Transcripción STAT5 , Síndrome de Sézary/genética , Transactivadores/sangre , Transactivadores/genética , Proteínas Supresoras de Tumor
15.
J Invest Dermatol ; 136(6): 1238-1246, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26872600

RESUMEN

Methylthioadenosine phosphorylase (MTAP) and the tumor suppressor genes CDKN2A-CDKN2B are frequently deleted in malignancies. The specific role of MTAP in cutaneous T-cell lymphoma subgroups, mycosis fungoides (MF) and Sézary syndrome (SS), is unknown. In 213 skin samples from patients with MF/SS, MTAP copy number loss (34%) was more frequent than CDKN2A (12%) in all cutaneous T-cell lymphoma stages using quantitative reverse transcription PCR. Importantly, in early stage MF, MTAP loss occurred independently of CDKN2A loss in 37% of samples. In peripheral blood mononuclear cells from patients with SS, codeletion with CDKN2A occurred in 18% of samples but loss of MTAP alone was uncommon. In CD4(+) cells from SS, reduced MTAP mRNA expression correlated with MTAP copy number loss (P < 0.01) but reduced MTAP expression was also detected in the absence of copy number loss. Deep sequencing of MTAP/CDKN2A-CDKN2B loci in 77 peripheral blood mononuclear cell DNA samples from patients with SS did not show any nonsynonymous mutations, but read-depth analysis suggested focal deletions consistent with MTAP and CDKN2A copy number loss detected with quantitative reverse transcription PCR. In a cutaneous T-cell lymphoma cell line, promoter hypermethylation was shown to downregulate MTAP expression and may represent a mechanism of MTAP inactivation. In conclusion, our findings suggest that there may be selection in early stages of MF for MTAP deletion within the cutaneous tumor microenvironment.


Asunto(s)
Eliminación de Gen , Regulación Neoplásica de la Expresión Génica , Linfoma Cutáneo de Células T/genética , Purina-Nucleósido Fosforilasa/genética , Neoplasias Cutáneas/genética , Adulto , Estudios de Cohortes , Metilación de ADN/genética , Femenino , Genes p16 , Humanos , Linfoma Cutáneo de Células T/patología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Neoplasias Cutáneas/patología , Células Tumorales Cultivadas , Microambiente Tumoral/genética
16.
J Invest Dermatol ; 118(6): 941-8, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12060387

RESUMEN

Primary cutaneous B cell lymphomas represent a distinct group of lymphoproliferative disorders that can be distinguished from systemic lymphoma by their good response to local treatment and favorable prognosis. In systemic B cell lymphoma, inactivation of p15(INK4b) and p16(INK4a) is frequently observed and may be associated with a poor prognosis. There have been no comprehensive studies in primary cutaneous B cell lymphomas, however. Mechanisms of p15/p16 inactivation include loss of heterozygosity, homozygous deletion, promotor region hypermethylation, and point mutation. We analyzed DNA from 36 cases of primary cutaneous B cell lymphomas, four systemic B cell lymphomas, and six benign B cell lymphoproliferative infiltrates for abnormalities of p15 and p16 using microsatellite markers for 9p21, methylation specific polymerase chain reaction, and polymerase chain reaction/single stranded conformational polymorphism analysis with exon specific primers. Expression of both p15 and p16 protein was assessed by immunohistochemistry. Loss of heterozygosity at 9p21 was identified in 2 out of 36 primary cutaneous B cell lymphomas. Hypermethylation of p15 and p16 promotor regions was identified in 8 of 35 (23%) and 15 of 35 (43%) cases, respectively. In two cases p16 hypermethylation was identified in recurrent disease but not in the initial tumor. No point mutations were identified. In seven patients, however, a polymorphism was observed in exon 3 of the p16 gene. In primary cutaneous B cell lymphomas with allelic loss or promotor hypermethylation of either p15 or p16, loss of expression in tumor cells was identified in 5 of 8 and 9 of 10 cases, respectively. Our findings suggest that p15(INK4b) and p16(INK4a) biallelic gene abnormalities are common in primary cutaneous B cell lymphomas, most frequently as a result of promotor hypermethylation. The presence of abnormalities in recurrent disease in some cases suggests that inactivation of p15 and p16 may be involved in disease progression.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Linfoma de Células B/genética , Linfoma de Células B/fisiopatología , Proteínas Supresoras de Tumor , Adulto , Anciano , Anciano de 80 o más Años , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Inhibidor p15 de las Quinasas Dependientes de la Ciclina , Metilación de ADN , Femenino , Eliminación de Gen , Regulación Neoplásica de la Expresión Génica , Humanos , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Mutación Puntual , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Regiones Promotoras Genéticas/fisiología
17.
J Invest Dermatol ; 121(4): 894-901, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14632210

RESUMEN

Fifty-one mycosis fungoides samples were analyzed for microsatellite instability (MSI) using the panel of markers recommended for hereditary nonpolyposis colorectal cancer kindred and a panel we designed for cutaneous T cell lymphoma in order to compare detection rates and determine if MSI is a genome-wide phenomenon. Samples demonstrating MSI were analyzed for abnormalities of the hMLH1 gene including loss of heterozygosity, mutations, and promoter hypermethylation. MSI was detected in 16% using the hereditary nonpolyposis colorectal cancer panel and 22% with the cutaneous T cell lymphoma panel. Overall, 27% demonstrated MSI and 73% had a stable phenotype. hMLH1 gene studies did not detect loss of heterozygosity or reveal any mutations. Promoter hypermethylation was detected in nine of 14 patients with MSI, however (64%). In addition hMLH1 and hMSH2 protein expression was studied using immunohistochemical techniques. Five of nine patients with MSI and hMLH1 promoter methylation showed abnormal hMLH1 protein expression with normal hMSH2 gene expression. All other patients tested demonstrated normal hMLH1 and hMSH2 protein expression. MSI was found to be more prevalent in tumor stage mycosis fungoides (47%) than early stage disease (20%) and was associated with an older age of onset of mycosis fungoides. MSI may be a consequence of hMLH1 promoter hypermethylation in mycosis fungoides patients and may prevent transcription in a subset of patients. This suggests that the development of a mutator phenotype may contribute to disease progression in mycosis fungoides.


Asunto(s)
Metilación de ADN , Proteínas de Unión al ADN , Repeticiones de Microsatélite/fisiología , Micosis Fungoide/fisiopatología , Proteínas de Neoplasias/genética , Neoplasias Cutáneas/fisiopatología , Proteínas Adaptadoras Transductoras de Señales , Proteínas Portadoras , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Homólogo 1 de la Proteína MutL , Proteína 2 Homóloga a MutS , Micosis Fungoide/metabolismo , Micosis Fungoide/mortalidad , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares , Fenotipo , Regiones Promotoras Genéticas/fisiología , Proteínas Proto-Oncogénicas/genética , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/mortalidad , Tasa de Supervivencia
18.
J Invest Dermatol ; 118(3): 493-9, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11874489

RESUMEN

There are few data on the molecular pathogenesis of cutaneous T cell lymphomas. A recent allelotyping study by our group identified frequent allelic loss on 9p, 10q, and 17p including losses on 9p21 in 16% of patients with mycosis fungoides and 46% with Sezary syndrome. The P15 and P16 genes are intricately linked on 9p21 and can be inactivated in melanoma and non-Hodgkin's lymphoma. We have therefore studied 76 patients with either mycosis fungoides or Sezary syndrome for abnormalities of these genes. DNA samples were analyzed for loss of heterozygosity, homozygous deletion, intragenic mutations, and promoter methylation. In addition P15 and P16 protein expression was assessed. Microsatellite analysis was informative in 73 of 76 cases: allelic loss on 9p21 was identified in 18 patients (25%), including 12 of 57 with mycosis fungoides (21%) and six of 16 with Sezary syndrome (37%). Single strand conformation polymorphism analysis of the entire coding regions of both genes did not identify any mutations, although two polymorphisms were identified including C613A, which has not previously been described. P15 and P16 gene promoter methylation was found in 45% and 29% of patients, respectively. Furthermore aberrant P15 protein expression was detected in 85% of patients analyzed with P15 gene abnormalities and abnormal P16 expression in 59% with P16 gene abnormalities. These abnormalities were not dependent on cutaneous stage of disease. This study suggests that abnormalities of the P15 and P16 genes are common in both early and advanced stages of mycosis fungoides and Sezary syndrome and that these genes may be inactivated by allelic loss and aberrant promoter methylation.


Asunto(s)
Proteínas de Ciclo Celular/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Genes p16/fisiología , Micosis Fungoide/genética , Síndrome de Sézary/genética , Proteínas Supresoras de Tumor , Proteínas de Ciclo Celular/metabolismo , Inhibidor p15 de las Quinasas Dependientes de la Ciclina , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Metilación de ADN , Análisis Mutacional de ADN , Eliminación de Gen , Frecuencia de los Genes , Homocigoto , Humanos , Inmunohistoquímica , Pérdida de Heterocigocidad , Micosis Fungoide/metabolismo , Polimorfismo Genético , Síndrome de Sézary/metabolismo
19.
Hematol Oncol Clin North Am ; 17(6): 1277-311, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14710885

RESUMEN

There is emerging evidence that genomic and chromosomal instability are features of CTCL, including variants such as MF, Sézary syndrome, and primary cutaneous CD30+ LCAL, and that specific chromosomal abnormalities are common. Additional resolution of specific regions of chromosomal loss and gain are required to define putative genes that may be of fundamental pathogenetic importance in CTCL. Inactivation of well-defined cell cycle and TSG are common as for other types of NHL. The prognostic significance of these abnormalities in CTCL has yet to be determined. The dysregulation of specific transcription factors is of interest, but requires further study. It is hoped that greater understanding of these molecular abnormalities will permit the development of CTCL-specific therapies that alleviate suffering and prolong survival.


Asunto(s)
Linfoma Cutáneo de Células T/patología , Neoplasias Cutáneas/patología , Aberraciones Cromosómicas , Cromosomas Humanos/genética , Cromosomas Humanos/ultraestructura , Técnicas Genéticas , Humanos , Inmunofenotipificación , Células Asesinas Naturales/patología , Linfoma de Células B/diagnóstico , Linfoma de Células B/patología , Linfoma Cutáneo de Células T/clasificación , Linfoma Cutáneo de Células T/diagnóstico , Linfoma Cutáneo de Células T/genética , Micosis Fungoide/diagnóstico , Micosis Fungoide/patología , Estadificación de Neoplasias , Transducción de Señal/genética , Neoplasias Cutáneas/clasificación , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/genética , Subgrupos de Linfocitos T/patología
20.
Arch Dermatol ; 140(4): 449-54, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15096373

RESUMEN

BACKGROUND: Chronic atopic eczema is not regarded as a precursor of malignancy, and, to our knowledge, there has been only one previous case report of CD30(+) cutaneous lymphoma in association with atopic dermatitis. OBSERVATIONS: We report 4 cases of CD30(+) lymphoproliferative disease in young adult patients with active atopic eczema dating from early childhood. Three patients developed primary cutaneous anaplastic large cell lymphoma, of whom 2 developed systemic disease and 1 died. The other patient developed lymphomatoid papulosis type A, which resolved after withdrawal of cyclosporine therapy. No other patient had received immunosuppressive therapy. Three had been treated with phototherapy, and 2 of these patients exhibited positive immunostaining for p53 within a proportion of the tumor cell population. CONCLUSIONS: Although we have not been able to establish a causative link, we believe that the association of these 2 conditions has not occurred by chance. Biopsies of lesional skin from subjects with atopic eczema exhibit a proportion of CD30 cells, and clonal transformation of this subpopulation might account for the CD30(+) lymphomas in our patients.


Asunto(s)
Dermatitis Atópica/complicaciones , Antígeno Ki-1/inmunología , Linfoma Cutáneo de Células T/complicaciones , Linfoma Cutáneo de Células T/patología , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/patología , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores/análisis , Biopsia con Aguja , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/patología , Fármacos Dermatológicos/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Inmunosupresores/uso terapéutico , Linfoma Cutáneo de Células T/tratamiento farmacológico , Masculino , Medición de Riesgo , Muestreo , Índice de Severidad de la Enfermedad , Neoplasias Cutáneas/tratamiento farmacológico , Resultado del Tratamiento
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