RESUMO
T-cell receptor gene beta (TCRß) gene rearrangement represents a complex, tightly regulated molecular mechanism involving excision, deletion and recombination of DNA during T-cell development. RUNX1, a well-known transcription factor for T-cell differentiation, has recently been described to act in addition as a recombinase cofactor for TCRδ gene rearrangements. In this work we employed a RUNX1 knock-out mouse model and demonstrate by deep TCRß sequencing, immunostaining and chromatin immunoprecipitation that RUNX1 binds to the initiation site of TCRß rearrangement and its homozygous inactivation induces severe structural changes of the rearranged TCRß gene, whereas heterozygous inactivation has almost no impact. To compare the mouse model results to the situation in Acute Lymphoblastic Leukemia (ALL) we analyzed TCRß gene rearrangements in T-ALL samples harboring heterozygous Runx1 mutations. Comparable to the Runx1+/- mouse model, heterozygous Runx1 mutations in T-ALL patients displayed no detectable impact on TCRß rearrangements. Furthermore, we reanalyzed published sequence data from recurrent deletion borders of ALL patients carrying an ETV6-RUNX1 translocation. RUNX1 motifs were significantly overrepresented at the deletion ends arguing for a role of RUNX1 in the deletion mechanism. Collectively, our data imply a role of RUNX1 as recombinase cofactor for both physiological and aberrant deletions.
Assuntos
Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Deleção de Genes , Rearranjo Gênico da Cadeia beta dos Receptores de Antígenos dos Linfócitos T/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas Proto-Oncogênicas c-ets/genética , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Proteínas Repressoras/genética , Animais , Linfócitos B , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Contagem de Linfócitos , Camundongos Knockout , Linfócitos T , Timo/patologia , Variante 6 da Proteína do Fator de Translocação ETSRESUMO
Depending on disease stage follicular lymphoma (FL) lack the t(14;18) in ~15-~50% of cases. Nevertheless, most of these cases express BCL2. To elucidate mechanisms triggering BCL2 expression and promoting pathogenesis in t(14;18)-negative FL, exonic single-nucleotide variant (SNV) profiles of 28 t(14;18)-positive and 13 t(14;18)-negative FL were analyzed, followed by the integration of copy-number changes, copy-neutral LOH and published gene-expression data as well as the assessment of immunoglobulin N-glycosylation sites. Typical FL mutations also affected t(14;18)-negative FL. Curated gene set/pathway annotation of genes mutated in either t(14;18)-positive or t(14;18)-negative FL revealed a strong enrichment of same or similar gene sets but also a more prominent or exclusive enrichment of immune response and N-glycosylation signatures in t(14;18)-negative FL. Mutated genes showed high BCL2 association in both subgroups. Among the genes mutated in t(14;18)-negative FL 555 were affected by copy-number alterations and/or copy-neutral LOH and 96 were differently expressed between t(14;18)-positive and t(14;18)-negative FL (P<0.01). N-glycosylation sites were detected considerably less frequently in t(14;18)-negative FL. These results suggest a diverse portfolio of genetic alterations that may induce or regulate BCL2 expression or promote pathogenesis of t(14;18)-negative FL as well as a less specific but increased crosstalk with the microenvironment that may compensate for the lack of N-glycosylation.
Assuntos
Biomarcadores Tumorais , Linfoma Folicular/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Glicosilação , Humanos , Região Variável de Imunoglobulina/genética , Linfoma Folicular/metabolismo , Mutação , Polimorfismo de Nucleotídeo Único , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Translocação Genética , Sequenciamento do ExomaAssuntos
Carcinoma Pulmonar de Células não Pequenas/complicações , Pé/fisiologia , Mãos/patologia , Ceratodermia Palmar e Plantar/diagnóstico , Neoplasias Pulmonares/complicações , Mastocitose Sistêmica/patologia , Idoso , Biópsia , Feminino , Humanos , Ceratodermia Palmar e Plantar/complicações , Ceratodermia Palmar e Plantar/patologia , Mastocitose Sistêmica/complicaçõesRESUMO
Approximately 15% of follicular lymphomas (FLs) lack breaks in the BCL2 locus. The aim of this study was to better define molecular and clinical features of BCL2-breakpoint/t(14;18)-negative FLs. We studied the presence of BCL2, BCL6 and MYC breaks by fluorescence in situ hybridization and the expression of BCL2, MUM1, CD10, P53 and Ki67 in large clinical trial cohorts of 540 advanced-stage FL cases and 116 early-stage disease FL patients treated with chemotherapy regimens and radiation, respectively. A total of 86% and 53% of advanced- and early-stage FLs were BCL2-breakpoint-positive, respectively. BCL2 was expressed in almost all FLs with BCL2 break and also in 86% and 69% of BCL2-breakpoint-negative advanced- and early-stage FLs, respectively. CD10 expression was significantly reduced in BCL2-breakpoint-negative FLs of all stages and MUM1 and Ki67 expression were significantly increased in BCL2-break-negative early-stage FLs. Patient characteristics did not differ between FLs with and without BCL2 breaks and neither did survival times in advanced-stage FLs. These results suggest that the molecular profile differs to some extent between FLs with and without BCL2 breaks and support the notion that FLs with and without BCL2 breaks belong to the same lymphoma entity.
Assuntos
Quebra Cromossômica , Regulação Neoplásica da Expressão Gênica , Linfoma Folicular/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Cromossomos Humanos Par 14/genética , Cromossomos Humanos Par 18/genética , Estudos de Coortes , Feminino , Seguimentos , Humanos , Linfoma Folicular/genética , Linfoma Folicular/mortalidade , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fenótipo , Prognóstico , Taxa de Sobrevida , Translocação Genética/genéticaRESUMO
In April 2013 our group published a review on predictive molecular pathology in this journal. Although only 2 years have passed many new facts and stimulating developments have happened in diagnostic molecular pathology rendering it worthwhile to present an up-date on this topic. A major technical improvement is certainly given by the introduction of next-generation sequencing (NGS; amplicon, whole exome, whole genome) and its application to formalin-fixed paraffin-embedded (FFPE) tissue in routine diagnostics. Based on this 'revolution' the analyses of numerous genetic alterations in parallel has become a routine approach opening the chance to characterize patients' malignant tumors much more deeply without increasing turn-around time and costs. In the near future this will open new strategies to apply 'off-label' targeted therapies, e.g. for rare tumors, otherwise resistant tumors etc. The clinically relevant genetic aberrations described in this review include mutation analyses of RAS (KRAS and NRAS), BRAF and PI3K in colorectal cancer, KIT or PDGFR alpha as well as BRAF, NRAS and KIT in malignant melanoma. Moreover, we present several recent advances in the molecular characterization of malignant lymphoma. Beside the well-known mutations in NSCLC (EGFR, ALK) a number of chromosomal aberrations (KRAS, ROS1, MET) have become relevant. Only very recently has the clinical need for analysis of BRCA1/2 come up and proven as a true challenge for routine diagnostics because of the genes' special structure and hot-spot-free mutational distribution. The genetic alterations are discussed in connection with their increasingly important role in companion diagnostics to apply targeted drugs as efficient as possible. As another aspect of the increasing number of druggable mutations, we discuss the challenges personalized therapies pose for the design of clinical studies to prove optimal efficacy particularly with respect to combination therapies of multiple targeted drugs and conventional chemotherapy. Such combinations would lead to an extremely high complexity that would hardly be manageable by applying conventional study designs for approval, e.g. by the FDA or EMA. Up-coming challenges such as the application of methylation assays and proteomic analyses on FFPE tissue will also be discussed briefly to open the door towards the ultimate goal of reading a patients' tissue as 'deeply' as possible. Although it is yet to be shown, which levels of biological information are most informative for predictive pathology, an integrated molecular characterization of tumors will likely offer the most comprehensive view for individualized therapy approaches. To optimize cancer treatment we need to understand tumor biology in much more detail on morphological, genetic, proteomic as well as epigenetic grounds. Finally, the complex challenges on the level of drug design, molecular diagnostics, and clinical trials make necessary a close collaboration among academic institutions, regulatory authorities and pharmaceutical companies.
Assuntos
Terapia de Alvo Molecular , Neoplasias/terapia , Antineoplásicos/uso terapêutico , Aberrações Cromossômicas , DNA de Neoplasias/genética , Desenho de Fármacos , Genes Neoplásicos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Técnicas de Diagnóstico Molecular , Terapia de Alvo Molecular/métodos , Terapia de Alvo Molecular/tendências , Mutação , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Neoplasias/diagnóstico , Neoplasias/genética , Neoplasias/patologia , Medicina de Precisão , Proteômica , Análise de Sequência de DNA/métodos , Terapias em EstudoRESUMO
Delayed reconstitution of the T cell compartment in recipients of allogeneic stem cell grafts is associated with an increase of reactivation of latent viruses. Thereby, the transplanted T cell repertoire appears to be one of the factors that affect T cell reconstitution. Therefore, we studied the T cell receptor beta (TCRß) gene rearrangements of flow cytometry-sorted CD4(+) and CD8(+) T cells from the peripheral blood of 23 allogeneic donors before G-CSF administration and on the day of apheresis. For this purpose, TCRß rearrangements were amplified by multiplex PCR followed by high-throughput amplicon sequencing. Overall, CD4(+) T cells displayed a significantly higher TCRß diversity compared to CD8(+) T cells irrespective of G-CSF administration. In line, no significant impact of G-CSF treatment on the TCR Vß repertoire usage was found. However, correlation of the donor T cell repertoire with clinical outcomes of the recipient revealed that a higher CD4(+) TCRß diversity after G-CSF treatment is associated with lower reactivation of cytomegalovirus and Epstein-Barr virus. By contrast, no protecting correlation was observed for CD8(+) T cells. In essence, our deep TCRß analysis identifies the importance of the CD4(+) T cell compartment for the control of latent viruses after allogeneic stem cell transplantation.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Antígenos HLA/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Transplante de Células-Tronco , Doadores de Tecidos , Ativação Viral , Adulto , Estudos de Casos e Controles , Feminino , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Transplante HomólogoRESUMO
Prognostically relevant risk factors in patients with diffuse large B-cell lymphoma (DLBCL) have predominantly been evaluated in elderly populations. We tested whether previously described risk factors are also valid in younger, poor-prognosis DLBCL patients. Paraffin-embedded samples from 112 patients with de novo DLBCL, enrolled in the R-MegaCHOEP trial of the German High Grade Non-Hodgkin Lymphoma Study Group (DSHNHL) were investigated using immunohistochemistry (MYC, FOXP1, LMO2, GCET1, CD5, CD10, BCL2, BCL6, IRF4/MUM1) and fluorescence in situ hybridization (MYC, BCL2, BCL6). MYC, BCL2 and BCL6 breaks occurred in 14, 21 and 31%, respectively. In the majority of cases, MYC was simultaneously rearranged with BCL2 and/or BCL6. The adverse impact of MYC rearrangements was confirmed, but the sole presence of BCL2 breaks emerged as a novel prognostic marker associated with inferior overall survival (OS) (P=0.002). Combined overexpression of MYC and BCL2 showed only limited association with inferior OS. All immunohistochemical cell of origin classifiers applied failed to predict survival time. DLBCL tumors with significant proportion of immunoblastic and/or immunoblastic-plasmacytoid cells had inferior OS, independently from from BCL2 break. Younger, poor-prognosis DLBCL patients, therefore, display different biological risk factors compared with an elderly population, with BCL2 translocations emerging as a powerful negative prognostic marker.
Assuntos
Biomarcadores Tumorais/metabolismo , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Adolescente , Adulto , Biomarcadores Tumorais/genética , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Hibridização in Situ Fluorescente , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-myc/genética , Fatores de Risco , Taxa de Sobrevida , Adulto JovemAssuntos
Regulação Neoplásica da Expressão Gênica , Doença de Hodgkin/metabolismo , Interleucina-15/metabolismo , Células de Reed-Sternberg/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Doença de Hodgkin/mortalidade , Humanos , Inflamação , Células Matadoras Naturais/citologia , Sistema de Sinalização das MAP Quinases , Fenótipo , Receptores de Interleucina-15/metabolismo , Transdução de Sinais , Resultado do TratamentoRESUMO
Recently published studies suggest a weak positive correlation between increased dietary acrylamide intake and the increased risk of endometrial and ovarian cancer. However, risk assessment of acrylamide remains difficult because the carcinogenic mechanisms are still unknown and in particular the molecular effects of low level acrylamide exposure as seen by dietary intake are not well understood. Therefore, we analyzed in ovarian and endometrial cancer cell lines as well as in primary hepatocytes the expression of genes involved in cancer development and xenobiotic metabolism after high and low dose exposure (1-0.001mM) of acrylamide and its metabolite glycidamide. In conclusion our in vitro results demonstrate that exposure to high doses of glycidamide/acrylamide - exceeding the dietary exposure of the general population by far - can induce genes with growth promoting potential like the oncogene cMYC and genes involved in the MAPK pathway. However, low-dose exposure seems to activate primarily genes involved in the elimination of the toxicant.
Assuntos
Acrilamida/toxicidade , Neoplasias do Endométrio/induzido quimicamente , Compostos de Epóxi/toxicidade , Hepatócitos/efeitos dos fármacos , Neoplasias Ovarianas/induzido quimicamente , Western Blotting , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Neoplasias do Endométrio/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Neoplasias Ovarianas/genética , RNA Neoplásico/química , RNA Neoplásico/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
The diagnostic differentiation between canine fibrosarcomas and peripheral nerve sheath tumours (PNSTs) is based on histopathological phenotype. Histological differentiation of these tumours can, however, be challenging and there is a lack of immunohistochemical markers to prove their histogenic origin. To identify possible PNST markers and to further characterize their histogenic origin we compared histologically well-defined canine fibrosarcomas and PNSTs by cDNA microarray analysis. Forty-five annotated gene products were significantly differentially expressed between both tumour types. Seven of these gene products, known to be specifically expressed in neuroectodermal tissues, had higher expression levels in PNSTs: FMN2, KIF1B, GLI1, ROBO1, NMUR2, DOK4 and HMG20B. Conversely, eight genes associated with carcinogenesis had higher expression in fibrosarcomas: FHL2, PLAGL1, FNBP1L, BAG2, HK1, CSK and Cox5A. Comparison of the fibrosarcoma and PNST transcriptome therefore identified PNST phenotype-associated genes involved in neuroectodermal differentiation, which may be useful as diagnostic markers. Furthermore, the genes associated with the fibrosarcoma phenotype may serve as markers to differentiate fibrosarcomas from other tumour types.
Assuntos
Doenças do Cão/diagnóstico , Doenças do Cão/genética , Fibrossarcoma/veterinária , Genes Neoplásicos/genética , Neoplasias de Bainha Neural/veterinária , Neoplasias Cutâneas/veterinária , Transcriptoma/genética , Animais , Biomarcadores Tumorais/genética , Diagnóstico Diferencial , Doenças do Cão/patologia , Cães , Fibrossarcoma/diagnóstico , Fibrossarcoma/genética , Regulação Neoplásica da Expressão Gênica/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias de Bainha Neural/diagnóstico , Neoplasias de Bainha Neural/genética , Proteínas do Tecido Nervoso/genética , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Receptores de Neurotransmissores/genética , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/genéticaRESUMO
The discovery of microRNA (miR) represents a novel paradigm in RNA-based regulation of gene expression and their dysregulation has become a hallmark of many a tumor. In virally associated cancers, the host-pathogen interaction could involve alteration in miR expression. Epstein-Barr virus (EBV)-encoded EBNA2 is indispensable for the capacity of the virus to transform B cells in vitro. Here, we studied how it affects cellular miRs. Extensive miR profiling of the virus-infected and EBNA2-transfected B lymphoma cells revealed that oncomiR miR-21 is positively regulated by this viral protein. Conversely, Burkitt's lymphoma (BL) cell lines infected with EBNA2 lacking P3HR1 strain did not show any increase in miR-21. EBNA2 increased phosphorylation of AKT and this was directly correlated with increased miR-21. In contrast, miR-146a was downregulated by EBNA2 in B lymphoma cells. Low miR-146a expression correlates with an elevated level of IRAK1 and type I interferon in EBNA2 transfectants. Taken together, the present data suggest that EBNA2 might contribute to EBV-induced B-cell transformation by altering miR expression and in particular by increasing oncomiR-like miR-21 and by affecting the antiviral responses of the innate immune system through downregulation of its key regulator miR-146a.
Assuntos
Antígenos Nucleares do Vírus Epstein-Barr/fisiologia , Herpesvirus Humano 4/genética , MicroRNAs/fisiologia , Proteínas Virais/fisiologia , Northern Blotting , Western Blotting , Linhagem Celular Tumoral , Antígenos Nucleares do Vírus Epstein-Barr/genética , Técnicas de Silenciamento de Genes , Humanos , MicroRNAs/genética , Proteínas Virais/genéticaRESUMO
The presence of circulating tumour cells (CTCs) in the peripheral blood is a prognostic factor for survival of human breast cancer patients. CTCs in the peripheral blood of dogs with mammary tumours have not been reported definitively. The present pilot study identifies mRNA markers for CTCs by comparing the transcriptome of canine mammary carcinoma cell lines CMM26 and CMM115 and peripheral blood leucocytes (PBLs). Genes with a 200-fold or higher mRNA expression in carcinoma cell lines were tested for specificity and sensitivity to detect CTCs using reverse transcriptase polymerase chain reaction (PCR). Six mRNA markers, AGR2, ATP8B1, CRYAB, F3 IRX3 and SLC1A1 were expressed in cell lines, but not PBL. All PCRs were able to detect one carcinoma cell admixed in 10(6) or more PBLs. The six mRNA markers may be suitable for detection of canine mammary CTCs and allow the analysis of their spatiotemporal distribution in dogs with mammary tumours.
Assuntos
Biomarcadores Tumorais/sangue , Doenças do Cão/diagnóstico , Neoplasias Mamárias Animais/diagnóstico , Células Neoplásicas Circulantes/metabolismo , Animais , Linhagem Celular Tumoral , Doenças do Cão/metabolismo , Cães , Feminino , Neoplasias Mamárias Animais/metabolismo , Análise em Microsséries , Sensibilidade e EspecificidadeRESUMO
Sporadic Burkitt lymphoma (sBL) can be delineated from diffuse large B-cell lymphoma (DLBCL) by a very homogeneous mRNA expression signature. However, it remained unclear whether all three BL variants-sBL, endemic BL (eBL) and human immunodeficiency virus-associated BL (HIV-BL)-represent a uniform biological entity despite their differences in geographical occurrence, association with immunodeficiency and/or incidence of Epstein-Barr virus (EBV) infection. To address this issue, we generated micro RNA (miRNA) profiles from 18 eBL, 31 sBL and 15 HIV-BL cases. In addition, we analyzed the miRNA expression of 86 DLBCL to determine whether miRNA profiles recapitulate the molecular differences between BL and DLBCL evidenced by mRNA profiling. A signature of 38 miRNAs containing MYC regulated and nuclear factor-kB pathway-associated miRNAs was obtained that differentiated BL from DLBCL. The miRNA profiles of sBL and eBL displayed only six differentially expressed miRNAs, whereas HIV and EBV infection had no impact on the miRNA profile of BL. In conclusion, miRNA profiling confirms that BL and DLBCL represent distinct lymphoma categories and demonstrates that the three BL variants are representatives of the same biological entity with only marginal miRNA expression differences between eBL and sBL.
Assuntos
Biomarcadores Tumorais/genética , Linfoma de Burkitt/genética , Perfilação da Expressão Gênica , Linfoma Difuso de Grandes Células B/genética , MicroRNAs/genética , Biomarcadores Tumorais/metabolismo , Linfoma de Burkitt/epidemiologia , Linfoma de Burkitt/metabolismo , Alemanha/epidemiologia , Humanos , Técnicas Imunoenzimáticas , Itália/epidemiologia , Quênia/epidemiologia , Linfoma Difuso de Grandes Células B/epidemiologia , Linfoma Difuso de Grandes Células B/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Proliferation, dedifferentiation and loss of cell-cell contacts are amongst the first steps of the metastatic cascade. The complex molecular pathways and gene expression changes associated with these events in canine mammary tumors are still largely undetermined. In this study, the transcriptome of 13 lymph node positive canine mammary carcinomas and corresponding non-neoplastic mammary glands were compared to identify the molecular pathways associated with metastatic progression. Differential gene expression was analyzed using gene set enrichment and pathway analysis and compared with gene expression data from human breast cancer. Metastatic canine carcinomas had 1312 significantly differentially expressed genes compared to normal mammary glands. This expression profile included a significant up-regulation of cell division and matrix invasion genes (MMP, SERPINE1, TIMP3). In contrast, genes associated with epithelial differentiation (EGF, EGFR, MAP2K6, STAT 5), cell adhesion (CLDN5, CTNNAL1, MUC1, PECAM1) and angiogenesis (ANGPT 2, ANGPTL1-4, FIGF, TIE1) were mostly down-regulated. Tumors had a significant decrease in membrane receptors and pathway gene expression (EGFR, FGFR1, GHR, PDGFR, TGFBR, TIE1) indicating a tendency towards independence from these proliferative stimuli. A number of the identified deregulated pathways overlapped with gene expression profiles of human breast cancer. Gene expression profiling of metastatic carcinomas, therefore, identified molecular pathways and functional gene families that are deregulated during malignant progression in canine mammary tumors.
Assuntos
Doenças do Cão/genética , Metástase Linfática/genética , Neoplasias Mamárias Animais/genética , Transcriptoma , Animais , Neoplasias da Mama/genética , Doenças do Cão/metabolismo , Doenças do Cão/patologia , Cães , Feminino , Perfilação da Expressão Gênica/veterinária , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Mamárias Animais/metabolismo , Neoplasias Mamárias Animais/patologia , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , RNA Mensageiro/genética , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismoRESUMO
BACKGROUND: Cellular senescence is a terminal cell-cycle arrest that occurs in response to activated oncogenes and DNA-damaging chemotherapy. Whether cancer cell senescence at diagnosis might be predictive for treatment outcome is unknown. METHODS: A senescence index (SI) was developed and used to retrospectively correlate the treatment outcome of 30 UICC stage IV colorectal cancer (CRC) patients with their SI at diagnosis. RESULTS: 5-Fluorouracil/leucovorin-treated CRC patients achieved a significantly longer progression-free survival when presenting with SI-positive tumours before therapy (median 12.0 vs 6.0 months; P=0.044). CONCLUSION: Cancer cell senescence predicts treatment outcome in metastasised CRC. Prospective analyses of larger patient cohorts are needed.
Assuntos
Senescência Celular , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/fisiopatologia , Neoplasias Colorretais/secundário , Intervalo Livre de Doença , Fluoruracila/uso terapêutico , Humanos , Leucovorina/uso terapêutico , Valor Preditivo dos Testes , Prognóstico , Resultado do TratamentoRESUMO
Deregulation of cell signaling pathways controlling cell growth and cell survival is a common feature of all cancers. Although a core repertoire of oncogenic mechanisms is widely conserved between various malignancies, the constellation of pathway activities can vary even in patients with the same malignant disease. Modern molecularly targeted cancer drugs intervene in cell signaling compensating for pathway deregulation. Hence characterizing tumors with respect to pathway activation will become crucial for treatment decisions. Here we have used semi-supervised machine learning methodology to generate signatures of eight oncogene-inducible pathways, which are conserved across epithelial and lymphoid tissues. We combined them to patterns of pathway activity called PAPs for pathway activation patterns and searched for them in 220 morphologically, immunohistochemically and genetically well-characterized mature aggressive B-cell lymphomas including 134 cases with clinical data available. Besides Burkitt lymphoma, which was characterized by a unique pattern, the PAPs identified four distinct groups of mature aggressive B-cell lymphomas across independent gene expression studies with distinct biological characteristics, genetic aberrations and prognosis. We confirmed our findings through cross-platform analysis in an independent data set of 303 mature aggressive B-cell lymphomas.
Assuntos
Biologia Computacional/métodos , Linfoma Difuso de Grandes Células B/metabolismo , Transdução de Sinais , Bases de Dados de Ácidos Nucleicos , Epitélio/metabolismo , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Linfonodos/metabolismo , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologiaRESUMO
A unique feature of the tumor cells (Hodgkin/Reed-Sternberg (HRS)) of classical Hodgkin lymphoma (cHL) is the loss of their B-cell phenotype despite their B-cell origin. Several lines of evidence suggest that epigenomic events, especially promoter DNA methylation, are involved in this silencing of many B-cell-associated genes. Here, we show that DNA demethylation alone or in conjunction with histone acetylation is not able to reconstitute the B-cell-gene expression program in cultured HRS cells. Instead, combined DNA demethylation and histone acetylation of B-cell lines induce an almost complete extinction of their B-cell-expression program and a tremendous upregulation of numerous Hodgkin-characteristic genes, including key players such as Id2 known to be involved in the suppression of the B-cell phenotype. Since the upregulation of Hodgkin-characteristic genes and the extinction of the B-cell-expression program occurred simultaneously, epigenetic changes may also be responsible for the malignant transformation of cHL. The epigenetic upregulation of Hodgkin-characteristic genes thus plays--in addition to promoter DNA hypermethylation of B-cell-associated genes--a pivotal role for the reprogramming of HRS cells and explains why DNA demethylation alone is unable to reconstitute the B-cell-expression program in HRS cells.
Assuntos
Linfócitos B/metabolismo , Metilação de DNA , Histonas/metabolismo , Doença de Hodgkin/patologia , Acetilação , Linfócitos B/patologia , Transformação Celular Neoplásica , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Doença de Hodgkin/genética , FenótipoRESUMO
PURPOSE: This study was undertaken to identify and compare the prognostic value of gene expression, chromosomal, and clinico-pathological data for the prediction of subsequent metastases in patients with primary uveal melanoma. PATIENTS AND METHODS: For comparison of different sets of predictor variables diagonal linear discriminant analysis was used. Chromosomal events were assessed by comparative genomic hybridization and gene expression profiling by microarray. Twenty-eight patients with a median follow-up of 68 months were analyzed, of whom 12 had developed subsequent metastases. RESULTS: Diagonal linear discriminant analysis with crossvalidation of gene expression data detected 42 genes as differentially expressed in metastasizing vsnon-metastasizing uveal melanomas in all 28 cases. Comparing quantitative scores of discriminant analysis, grouping precision was significant better with gene expression profiling compared to comparative genomic hybridization (P=0.01) and to clinical data (P=0.001). Two published gene lists associated with monosomy 3 and metastatic tumor growth were used as classifier for discriminant analysis and yielded superior classification in patients with and without subsequent metastases than chromosomal or clinico-pathological data. CONCLUSION: In our patient cohort gene expression profiling of primary uveal melanoma tissue was superior to clinical-pathological and chromosomal analysis to assess for the risk of subsequent metastases.