RESUMEN
Approximately one-third of patients with diffuse large B-cell lymphoma (DLBCL) relapse and often require salvage chemotherapy followed by autologous stem cell transplantation. In most cases, the clonal relationship between the first diagnosis and subsequent relapse is not assessed, thereby potentially missing the identification of second primary lymphoma. In this study, the clonal relationship of 59 paired DLBCL diagnoses and recurrences was established by next-generation sequencing-based detection of immunoglobulin gene rearrangements. Among 50 patients with interpretable results, 43 patients (86%) developed clonally related relapsed disease. This was observed in 100% of early recurrences (<2 years), 80% of the recurrences with an interval between 2 and 5 years, and 73% of late recurrences (≥5 years). On the other hand, 7 (14%) out of 50 patients displayed different dominant clonotypes in primary DLBCL and clinical recurrences, confirming the occurrence of second primary DLBCL; 37% of DLBCL recurrences that occurred ≥4 years after diagnosis were shown to be second primary lymphomas. The clonally unrelated cases were Epstein-Barr virus positive in 43% of the cases, whereas this was only 5% in the relapsed DLBCL cases. In conclusion, next-generation sequencing-based clonality testing in late recurrences should be considered in routine diagnostics to distinguish relapse from second primary lymphoma, as this latter group of patients with DLBCL may benefit from less-intensive treatment strategies.
Asunto(s)
Infecciones por Virus de Epstein-Barr , Trasplante de Células Madre Hematopoyéticas , Linfoma de Células B Grandes Difuso , Humanos , Infecciones por Virus de Epstein-Barr/patología , Recurrencia Local de Neoplasia/patología , Herpesvirus Humano 4 , Trasplante Autólogo , Linfoma de Células B Grandes Difuso/diagnóstico , Linfoma de Células B Grandes Difuso/genética , Linfoma de Células B Grandes Difuso/tratamiento farmacológicoRESUMEN
Clonality analysis in classic Hodgkin lymphoma (cHL) is of added value for correctly diagnosing patients with atypical presentation or histology reminiscent of T cell lymphoma, and for establishing the clonal relationship in patients with recurrent disease. However, such analysis has been hampered by the sparsity of malignant Hodgkin and Reed-Sternberg (HRS) cells in a background of reactive immune cells. Recently, the EuroClonality-NGS Working Group developed a novel next-generation sequencing (NGS)-based assay and bioinformatics platform (ARResT/Interrogate) to detect immunoglobulin (IG) gene rearrangements for clonality testing in B-cell lymphoproliferations. Here, we demonstrate the improved performance of IG-NGS compared to conventional BIOMED-2/EuroClonality analysis to detect clonal gene rearrangements in 16 well-characterized primary cHL cases within the IG heavy chain (IGH) and kappa light chain (IGK) loci. This was most obvious in formalin-fixed paraffin-embedded (FFPE) tissue specimens, where three times more clonal cases were detected with IG-NGS (9 cases) compared to BIOMED-2 (3 cases). In total, almost four times more clonal rearrangements were detected in FFPE with IG-NGS (N = 23) as compared to BIOMED-2/EuroClonality (N = 6) as judged on identical IGH and IGK targets. The same clonal rearrangements were also identified in paired fresh frozen cHL samples. To validate the neoplastic origin of the detected clonotypes, IG-NGS clonality analysis was performed on isolated HRS cells, demonstrating identical clonotypes as detected in cHL whole-tissue specimens. Interestingly, IG-NGS and HRS single-cell analysis after DEPArray™ digital sorting revealed rearrangement patterns and copy number variation profiles indicating clonal diversity and intratumoral heterogeneity in cHL. Our data demonstrate improved performance of NGS-based detection of IG gene rearrangements in cHL whole-tissue specimens, providing a sensitive molecular diagnostic assay for clonality assessment in Hodgkin lymphoma.
Asunto(s)
Genes de Inmunoglobulinas , Enfermedad de Hodgkin , Variaciones en el Número de Copia de ADN , Reordenamiento Génico , Secuenciación de Nucleótidos de Alto Rendimiento , Enfermedad de Hodgkin/diagnóstico , Enfermedad de Hodgkin/genética , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genéticaRESUMEN
Motivation: The study of immunoglobulins and T cell receptors using next-generation sequencing has finally allowed exploring immune repertoires and responses in their immense variability and complexity. Unsurprisingly, their analysis and interpretation is a highly convoluted task. Results: We thus implemented ARResT/Interrogate, a web-based, interactive application. It can organize and filter large amounts of immunogenetic data by numerous criteria, calculate several relevant statistics, and present results in the form of multiple interconnected visualizations. Availability and Implementation: ARResT/Interrogate is implemented primarily in R, and is freely available at http://bat.infspire.org/arrest/interrogate/ Contact: nikos.darzentas@gmail.com Supplementary Information: Supplementary data are available at Bioinformatics online.
Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Inmunogenética/métodos , Inmunoglobulinas/genética , Receptores de Antígenos de Linfocitos T/metabolismo , Programas Informáticos , Variación Genética , Humanos , Receptores de Antígenos de Linfocitos T/genéticaRESUMEN
AIMS: To investigate the spectrum of mutations in 20 genes involved in B-cell receptor and/or Toll-like receptor signalling resulting in activation of nuclear factor-κB (NF-κB) in 20 nodal marginal zone lymphomas (NMZLs), 20 follicular lymphomas (FLs), and 11 cases of B-cell lymphoma, unclassifiable (BCL-u). METHODS AND RESULTS: Nodal marginal zone lymphomas were diagnosed according to strict criteria, including the expression of at least one putative marginal zone marker (MNDA and/or IRTA1). Cases that showed features of NMZL but did not fulfil all criteria were included as BCL-u. All FLs were required to have a BCL2 rearrangement. Mutations were found in: nine NMZLs, with recurrent mutations in TNFAIP3 and CD79B; 12 FLs, with recurrent mutations in TNFRSF14, TNFAIP3, and CARD11; and five cases of BCL-u, with recurrent mutations in TNFRSF14. TNFRSF14 mutations were present in FL and BCL-u, but not in any of the NMZLs. In the BCL-u group, TNFRSF14 mutations clustered with a FL immunophenotype. CONCLUSIONS: These results suggest that TNFRSF14 mutations point towards a diagnosis of FL, and can be used in the sometimes difficult distinction between NMZL and FL, but to apply this in diagnostics would require confirmation in an independent cohort. In addition, the presence or absence of specific mutations in pathways converging on NF-κB could be important for decisions regarding targeted treatment.
Asunto(s)
Biomarcadores de Tumor/genética , Linfoma de Células B de la Zona Marginal/genética , FN-kappa B/genética , Miembro 14 de Receptores del Factor de Necrosis Tumoral/genética , Anciano , Diagnóstico Diferencial , Supervivencia sin Enfermedad , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Linfoma de Células B de la Zona Marginal/diagnóstico , Linfoma Folicular/diagnóstico , Linfoma Folicular/genética , Masculino , Persona de Mediana Edad , Mutación , Transducción de Señal/genéticaRESUMEN
AIMS: For patients who have multiple lymphomas with discordant pathology, it is relevant to determine whether there is one disseminated lymphoma or two unrelated lymphomas. Patients with disseminated, clonally related lymphomas are usually treated with the most powerful drugs available, while patients with unrelated (primary) lymphomas receive mainly standard first-line therapies. METHODS AND RESULTS: We used next-generation sequencing on the Ion Torrent Personal Genome Machine to characterize the immunoglobulin heavy gene V-D-J rearrangements in two diagnostic tissue samples, including formalin-fixed and paraffin-embedded tissue, of two patients with iatrogenic immunodeficiency-associated Epstein-Barr virus lymphoproliferative disorder, with ulcerative colitis as underlying disease. The immunoglobulin rearrangement sequences obtained by next-generation sequencing revealed undoubtedly clonally related lesions in two tissue biopsies that were taken over time in the first patient, which is concordant with disseminated lymphoma. The other patient showed two clonally unrelated lesions, which is incompatible with clonal dissemination. This information was not inferred from evaluation of the heavy and light chain rearrangements by fragment analysis, which is currently the gold standard. CONCLUSION: Our study demonstrates the diagnostic application of next-generation sequencing of immunoglobulin rearrangement assessment in pathology for clinical decision-making in patients with several simultaneous or subsequent lymphoproliferations.
Asunto(s)
Colitis Ulcerosa/genética , Cadenas Pesadas de Inmunoglobulina/genética , Linfoma/genética , Trastornos Linfoproliferativos/genética , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/patología , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Linfoma/complicaciones , Linfoma/patología , Trastornos Linfoproliferativos/complicaciones , Trastornos Linfoproliferativos/patología , Persona de Mediana Edad , Adulto JovenRESUMEN
OBJECTIVE: The aim of this study was to evaluate a series of primary melanomas of the female urogenital tract for oncogenic mutations in KIT, NRAS and BRAF in order to identify patients who may be amenable to targeted therapy. METHODS: We reviewed twenty-four cases of female urogenital tract melanomas and used Sanger sequencing analysis for the detection of oncogenic mutations in exons 9, 11, 13, and 17 of KIT; exons 2 and 3 of NRAS; and exon 15 of BRAF. RESULTS: Twenty-four patients were included: fourteen vaginal melanomas, four cervical melanomas, five urethral melanomas and one vulvar melanoma. NRAS mutations (4/24, 21%) were more prevalent than KIT mutations (1/24, 4%), while BRAF mutations were absent. Three of four NRAS mutations were present in vaginal melanomas (21%), mainly affecting codon 61 (3/4). They were mutually exclusive with the KIT mutation. The KIT mutation was present in a vaginal melanoma and affected exon 17. CONCLUSIONS: Melanomas of the female urogenital tract relatively commonly harbor mutations in NRAS; this makes NRAS an interesting therapeutic target for these patients in the advanced setting. KIT mutations were rare in our study in contrast to some previous reports. We cannot exclude that anatomical site-related differences and/or population related differences in KIT mutation frequency exist within urogenital tract melanomas.
Asunto(s)
GTP Fosfohidrolasas/genética , Neoplasias de los Genitales Femeninos/genética , Melanoma/genética , Proteínas de la Membrana/genética , Mutación , Neoplasias Ureterales/genética , Adulto , Anciano , Anciano de 80 o más Años , Exones , Femenino , Formaldehído , Neoplasias de los Genitales Femeninos/enzimología , Neoplasias de los Genitales Femeninos/epidemiología , Humanos , Sistema de Señalización de MAP Quinasas , Melanoma/enzimología , Melanoma/epidemiología , Persona de Mediana Edad , Epidemiología Molecular , Países Bajos/epidemiología , Adhesión en Parafina , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas c-kit/genética , Estudios Retrospectivos , Fijación del TejidoRESUMEN
The histopathological diagnosis of diffuse gliomas often lacks the precision that is needed for tailored treatment of individual patients. Assessment of the molecular aberrations will probably allow more robust and prognostically relevant classification of these tumors. Markers that have gained a lot of interest in this respect are co-deletion of complete chromosome arms 1p and 19q, (hyper)methylation of the MGMT promoter and IDH1 mutations. The aim of this study was to assess the prognostic significance of complete 1p/19q co-deletion, MGMT promoter methylation and IDH1 mutations in patients suffering from diffuse gliomas. The presence of these molecular aberrations was investigated in a series of 561 diffuse astrocytic and oligodendroglial tumors (low grade n=110, anaplastic n=118 and glioblastoma n=333) and correlated with age at diagnosis and overall survival. Complete 1p/19q co-deletion, MGMT promoter methylation and/or IDH1 mutation generally signified a better prognosis for patients with a diffuse glioma including glioblastoma. However, in all 10 patients with a histopathological diagnosis of glioblastoma included in this study complete 1p/19q co-deletion was not associated with improved survival. Furthermore, in glioblastoma patients >50 years of age the favorable prognostic significance of IDH1 mutation and MGMT promoter methylation was absent. In conclusion, molecular diagnostics is a powerful tool to obtain prognostically relevant information for glioma patients. However, for individual patients the molecular information should be interpreted with caution and weighed in the context of parameters such as age and histopathological diagnosis.
Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Encefálicas/genética , Deleción Cromosómica , Cromosomas Humanos Par 19 , Cromosomas Humanos Par 1 , Glioma/genética , Adulto , Neoplasias Encefálicas/clasificación , Neoplasias Encefálicas/mortalidad , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 19/genética , Metilación de ADN , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Femenino , Eliminación de Gen , Glioma/clasificación , Glioma/mortalidad , Humanos , Isocitrato Deshidrogenasa/genética , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Mutación , Patología Molecular , Pronóstico , Regiones Promotoras Genéticas , Proteínas Supresoras de Tumor/genéticaRESUMEN
Introduction: Activated B cells play a key role in the pathogenesis of primary Sjögren's syndrome (pSS) through the production of autoantibodies and the development of ectopic germinal centers in the salivary glands and other affected sites. Around 5-10% of pSS patients develop B-cell lymphoma, usually extranodal marginal zone lymphomas (eMZL) of the mucosa-associated lymphoid tissue (MALT). The aim of the current study is to investigate if the eMZL clonotype is detectable in prediagnostic blood and tissue biopsies of pSS patients. Methods/Results: We studied prediagnostic tissue biopsies of three pSS patients diagnosed with eMZL and four pSS controls through immunoglobulin (IG) gene repertoire sequencing. In all three cases, we observed the eMZL clonotype in prediagnostic tissue biopsies. Among controls, we observed transient elevation of clonotypes in two pSS patients. To evaluate if eMZL clonotypes may also be detected in the circulation, we sequenced a peripheral blood mononuclear cell (PBMC) sample drawn at eMZL diagnosis and two years prior to eMZL relapse in two pSS patients. The eMZL clonotype was detected in the peripheral blood prior to diagnosis in both cases. Next, we selected three pSS patients who developed eMZL lymphoma and five additional pSS patients who remained lymphoma-free. We sequenced the IG heavy chain (IGH) gene repertoire in PBMC samples taken a median of three years before eMZL diagnosis. In two out of three eMZL patients, the dominant clonotype in the prediagnostic PBMC samples matched the eMZL clonotype in the diagnostic biopsy. The eMZL clonotypes observed consisted of stereotypic IGHV gene combinations (IGHV1-69/IGHJ4 and IGHV4-59/IGHJ5) associated with rheumatoid factor activity, a previously reported feature of eMZL in pSS. Discussion: In conclusion, our results indicate that eMZL clonotypes in pSS patients are detectable prior to overt eMZL diagnosis in both tissue biopsies and peripheral blood through immunogenetic sequencing, paving the way for the development of improved methods of early detection of eMZL.
RESUMEN
Patients with lymphoplasmacytic lymphoma/Waldenström macroglobulinemia (LPL/WM) occasionally develop diffuse large B-cell lymphoma (DLBCL). This mostly results from LPL/WM transformation, although clonally unrelated DLBCL can also arise. LPL/WM is characterized by activating MYD88L265P (>95%) and CXCR4 mutations (~30%), but the genetic drivers of transformation remain to be identified. Here, in thirteen LPL/WM patients who developed DLBCL, the clonal relationship of LPL and DLBCL together with mutations contributing to transformation were investigated. In 2 LPL/WM patients (15%), high-throughput sequencing of immunoglobulin gene rearrangements showed evidence of >1 clonal B-cell population in LPL tissue biopsies. In the majority of LPL/WM patients, DLBCL presentations were clonally related to the dominant clone in LPL, providing evidence of transformation. However, in 3 patients (23%), DLBCL was clonally unrelated to the major malignant B-cell clone in LPL, of which 2 patients developed de novo DLBCL. In this study cohort, LPL displayed MYD88L265P mutation in 8 out of eleven patients analyzed (73%), while CXCR4 mutations were observed in 6 cases (55%). MYD88WT LPL biopsies present in 3 patients (27%) were characterized by CD79B and TNFAIP3 mutations. Upon transformation, DLBCL acquired novel mutations targeting BTG1, BTG2, CD79B, CARD11, TP53, and PIM1. Together, we demonstrate variable clonal B-cell dynamics in LPL/WM patients developing DLBCL, and the occurrence of clonally unrelated DLBCL in about one-quarter of LPL/WM patients. Moreover, we identified commonly mutated genes upon DLBCL transformation, which together with preserved mutations already present in LPL characterize the mutational landscape of DLBCL occurrences in LPL/WM patients.
RESUMEN
Despite high cure rates in classic Hodgkin lymphoma (cHL), relapses are observed. Whether relapsed cHL represents second primary lymphoma or an underlying T-cell lymphoma (TCL) mimicking cHL is underinvestigated. To analyze the nature of cHL recurrences, in-depth clonality testing of immunoglobulin (Ig) and T-cell receptor (TCR) rearrangements was performed in paired cHL diagnoses and recurrences among 60 patients, supported by targeted mutation analysis of lymphoma-associated genes. Clonal Ig rearrangements were detected by next-generation sequencing (NGS) in 69 of 120 (58%) diagnoses and recurrence samples. The clonal relationship could be established in 34 cases, identifying clonally related relapsed cHL in 24 of 34 patients (71%). Clonally unrelated cHL was observed in 10 of 34 patients (29%) as determined by IG-NGS clonality assessment and confirmed by the identification of predominantly mutually exclusive gene mutations in the paired cHL samples. In recurrences of >2 years, â¼60% of patients with cHL for whom the clonal relationship could be established showed a second primary cHL. Clonal TCR gene rearrangements were identified in 14 of 125 samples (11%), and TCL-associated gene mutations were detected in 7 of 14 samples. Retrospective pathology review with integration of the molecular findings were consistent with an underlying TCL in 5 patients aged >50 years. This study shows that cHL recurrences, especially after 2 years, sometimes represent a new primary cHL or TCL mimicking cHL, as uncovered by NGS-based Ig/TCR clonality testing and gene mutation analysis. Given the significant therapeutic consequences, molecular testing of a presumed relapse in cHL is crucial for subsequent appropriate treatment strategies adapted to the specific lymphoma presentation.
Asunto(s)
Enfermedad de Hodgkin , Linfoma de Células T , Linfoma , Humanos , Enfermedad de Hodgkin/diagnóstico , Enfermedad de Hodgkin/genética , Enfermedad de Hodgkin/patología , Estudios Retrospectivos , Recurrencia Local de Neoplasia , InmunoglobulinasAsunto(s)
Neoplasias del Sistema Nervioso Central/genética , Melanoma/genética , Melanosis/genética , Síndromes Neurocutáneos/genética , Neoplasias del Sistema Nervioso Central/diagnóstico , Variaciones en el Número de Copia de ADN , Humanos , Melanoma/diagnóstico , Melanosis/diagnóstico , Síndromes Neurocutáneos/diagnósticoRESUMEN
Clonality assessment of the Ig heavy- and light-chain genes (IGH and IGK) using GeneScan analysis is an important supplemental assay in diagnostic testing for lymphoma. Occasionally cases with an IGK rearrangement pattern that cannot readily be assigned to a monoclonal lymphoma are encountered, whereas the occurrence of biclonal lymphomas is rare, and the result of the IGH locus of these cases is in line with monoclonality. Three such ambiguous cases were assessed for clonality using next-generation sequencing. Information on the sequences of the rearrangements, combined with knowledge of the complex organization of the IGK locus, pointed to two explanations that can attribute seemingly biclonal IGK rearrangements to a single clone. In two cases, this explanation involved inversion rearrangements on the IGK locus, whereas in the third case, the cross-reactivity of primers generated an additional clonal product. In conclusion, next-generation sequencing-based clonality assessment allows for the detection of both inversion rearrangements and the cross-reactivity of primers, and can therefore facilitate the interpretation of cases of lymphoma with complex IGK rearrangement patterns.
Asunto(s)
Linfocitos B/inmunología , Células Clonales/inmunología , Reordenamiento Génico , Genes de Inmunoglobulinas , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Cadenas kappa de Inmunoglobulina/genética , Linfoma de Células B/genética , Linfoma Folicular/genética , Sitios Genéticos , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Intrones , Fenotipo , Inversión de SecuenciaRESUMEN
Ig gene (IG) clonality analysis has an important role in the distinction of benign and malignant B-cell lymphoid proliferations and is mostly performed with the conventional EuroClonality/BIOMED-2 multiplex PCR protocol and GeneScan fragment size analysis. Recently, the EuroClonality-NGS Working Group developed a method for next-generation sequencing (NGS)-based IG clonality analysis. Herein, we report the results of an international multicenter biological validation of this novel method compared with the gold standard EuroClonality/BIOMED-2 protocol, based on 209 specimens of reactive and neoplastic lymphoproliferations. NGS-based IG clonality analysis showed a high interlaboratory concordance (99%) and high concordance with conventional clonality analysis (98%) for the molecular conclusion. Detailed analysis of the individual IG heavy chain and kappa light chain targets showed that NGS-based clonality analysis was more often able to detect a clonal rearrangement or yield an interpretable result. NGS-based and conventional clonality analysis detected a clone in 96% and 95% of B-cell neoplasms, respectively, and all but one of the reactive cases were scored polyclonal. We conclude that NGS-based IG clonality analysis performs comparable to conventional clonality analysis. We provide critical parameters for interpretation and discuss a first step toward a quantitative scoring approach for NGS clonality results. Considering the advantages of NGS-based clonality analysis, including its high sensitivity and possibilities for accurate clonal comparison, this supports implementation in diagnostic practice.
Asunto(s)
Linfocitos B/inmunología , Células Clonales/inmunología , Reordenamiento Génico , Genes de Inmunoglobulinas , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Linfoma de Células B/genética , Linfoma Folicular/genética , Exactitud de los Datos , Humanos , Reacción en Cadena de la Polimerasa Multiplex/métodos , Fenotipo , Sensibilidad y EspecificidadAsunto(s)
Linfocitos B/metabolismo , Evolución Clonal/genética , Infecciones por Virus de Epstein-Barr/complicaciones , Herpesvirus Humano 4 , Inmunoglobulinas/genética , Trastornos Linfoproliferativos/etiología , Linfocitos B/patología , Linfocitos B/virología , Humanos , Inmunoglobulinas/inmunología , Trastornos Linfoproliferativos/diagnóstico , Estadificación de Neoplasias , Evaluación del Resultado de la Atención al PacienteRESUMEN
One of the hallmarks of B lymphoid malignancies is a B cell clone characterized by a unique footprint of clonal immunoglobulin (IG) gene rearrangements that serves as a diagnostic marker for clonality assessment. The EuroClonality/BIOMED-2 assay is currently the gold standard for analyzing IG heavy chain (IGH) and κ light chain (IGK) gene rearrangements of suspected B cell lymphomas. Here, the EuroClonality-NGS Working Group presents a multicentre technical feasibility study of a novel approach involving next-generation sequencing (NGS) of IGH and IGK loci rearrangements that is highly suitable for detecting IG gene rearrangements in frozen and formalin-fixed paraffin-embedded tissue specimens. By employing gene-specific primers for IGH and IGK amplifying smaller amplicon sizes in combination with deep sequencing technology, this NGS-based IG clonality analysis showed robust performance, even in DNA samples of suboptimal DNA integrity, and a high clinical sensitivity for the detection of clonal rearrangements. Bioinformatics analyses of the high-throughput sequencing data with ARResT/Interrogate, a platform developed within the EuroClonality-NGS Working Group, allowed accurate identification of clonotypes in both polyclonal cell populations and monoclonal lymphoproliferative disorders. This multicentre feasibility study is an important step towards implementation of NGS-based clonality assessment in clinical practice, which will eventually improve lymphoma diagnostics.
Asunto(s)
Reordenamiento Génico/genética , Genes de Inmunoglobulinas/genética , Estudios de Factibilidad , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas kappa de Inmunoglobulina/genética , Linfoma de Células B/genética , Trastornos Linfoproliferativos/genéticaRESUMEN
Assessment of clonality, marker identification and measurement of minimal residual disease (MRD) of immunoglobulin (IG) and T cell receptor (TR) gene rearrangements in lymphoid neoplasms using next-generation sequencing (NGS) is currently under intensive development for use in clinical diagnostics. So far, however, there is a lack of suitable quality control (QC) options with regard to standardisation and quality metrics to ensure robust clinical application of such approaches. The EuroClonality-NGS Working Group has therefore established two types of QCs to accompany the NGS-based IG/TR assays. First, a central polytarget QC (cPT-QC) is used to monitor the primer performance of each of the EuroClonality multiplex NGS assays; second, a standardised human cell line-based DNA control is spiked into each patient DNA sample to work as a central in-tube QC and calibrator for MRD quantification (cIT-QC). Having integrated those two reference standards in the ARResT/Interrogate bioinformatic platform, EuroClonality-NGS provides a complete protocol for standardised IG/TR gene rearrangement analysis by NGS with high reproducibility, accuracy and precision for valid marker identification and quantification in diagnostics of lymphoid malignancies.
Asunto(s)
Marcadores Genéticos/genética , Inmunoglobulinas/genética , Receptores de Antígenos de Linfocitos T/genética , Biología Computacional/métodos , Reordenamiento Génico/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Neoplasia Residual/genética , Control de Calidad , Reproducibilidad de los ResultadosRESUMEN
Tumors are complex tissues composed of neoplastic cells, soluble and insoluble matrix components and stromal cells. Here we report that in melanoma, turn-over of type I collagen (Col(I)), the predominant matrix protein in dermal stroma affects melanoma progression. Fibroblasts juxtaposed to melanoma cell nests within the papillary dermis display high levels of Col(I) mRNA expression. These nests are enveloped by collagen fibers. In contrast, melanoma-associated fibroblasts within the reticular dermis express Col(I) mRNA at a level that is comparable to its expression in uninvolved dermis and reduced amount of collagen protein can be observed. To determine the significance of Col(I) expression in melanoma, we pharmacologically inhibited its transcription in a porcine cutaneous melanoma model by oral administration of halofuginone. When administered before melanoma development, it reduced melanoma incidence and diminished the transition from microinvasive toward deeply invasive growth by limiting the development of a tumor vasculature. Whereas invasive melanoma growth has been correlated with increased blood vessel density previously, our data for the first time demonstrate that the proangiogenic effect of Col(I) expression by fibroblasts and vascular cells precedes the development of invasive melanomas in a de novo tumor model.
Asunto(s)
Colágeno Tipo I/metabolismo , Melanoma/metabolismo , Invasividad Neoplásica , Neovascularización Patológica/metabolismo , Neoplasias Cutáneas/metabolismo , Inhibidores de la Angiogénesis/farmacología , Animales , Colágeno Tipo I/efectos de los fármacos , Humanos , Inmunohistoquímica , Hibridación in Situ , Melanoma/irrigación sanguínea , Melanoma/patología , Invasividad Neoplásica/fisiopatología , Piperidinas/farmacología , Quinazolinonas/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Cutáneas/irrigación sanguínea , Neoplasias Cutáneas/patología , Porcinos , Porcinos EnanosRESUMEN
To further elucidate the genetic underpinnings of uveal melanoma (UM) and identify new markers that correlate with disease outcome, archival formalin-fixed, paraffin-embedded enucleation specimens from 25 patients with UM and a mean follow-up of 14 years were analyzed for whole-genome copy-number alterations using OncoScan analysis. Copy-number alterations of chromosomes 1, 3, 6, and 8 were also analyzed in these tumors using multiplex ligation-dependent probe-amplification, and mutations in GNAQ, GNA11, and BAP1 were searched for by Sanger sequencing. Our study confirms the previously reported GNAQ and GNA11 mutation frequencies in UMs as well as the presence of monosomy 3 as a factor strongly indicating poor prognosis. Two cases with metastatic disease, but without monosomy of chromosome 3, showed loss of a small region in the distal part of chromosome 2p. Also, UMs leading to metastatic disease had more chromosomal aberrations than those without metastases. Three UMs lacking a GNAQ or a GNA11 mutation showed a gain of chromosome 8q; one of these cases showed extensive chromothripsis. Another case (with suspect lung metastasis) showed focal chromothripsis. Our whole-genome copy-number analysis shows that focal loss of chromosome 2p may be involved in the metastatic spread of UMs without monosomy 3; metastatic UMs carry more chromosomal aberrations than those without metastases; and chromothripsis may play a role in the oncogenesis of UMs, but does not necessarily indicate a poor prognosis. The clinical and particularly diagnostic utility of these findings needs to be corroborated in a larger set of patients with UM.
Asunto(s)
Carcinogénesis , Aberraciones Cromosómicas , Variaciones en el Número de Copia de ADN , Melanoma/genética , Modelos Genéticos , Neoplasias de la Úvea/genética , Centros Médicos Académicos , Adulto , Anciano , Coroides/metabolismo , Coroides/patología , Cuerpo Ciliar/metabolismo , Cuerpo Ciliar/patología , Femenino , Estudios de Seguimiento , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Melanoma/diagnóstico , Melanoma/metabolismo , Melanoma/patología , Melanoma/secundario , Persona de Mediana Edad , Mutación , Países Bajos , Pronóstico , Estudios Retrospectivos , Translocación Genética , Neoplasias de la Úvea/diagnóstico , Neoplasias de la Úvea/metabolismo , Neoplasias de la Úvea/patologíaRESUMEN
Limited data is available on the genetic features of primary leptomeningeal melanocytic neoplasms (LMNs). Similarities with uveal melanoma were recently suggested as both entities harbor oncogenic mutations in GNAQ and GNA11. Whether primary LMNs share additional genetic alterations with uveal melanoma including copy number variations is unknown. Twenty primary LMNs ranging from benign and intermediate-grade melanocytomas to melanomas were tested by direct sequencing for hotspot mutations in the genes GNA11, GNAQ, BRAF, NRAS and HRAS. Furthermore, the lesions were tested for copy number variations of chromosomes frequently present in uveal melanoma (1p, 3, 6 and 8q) by multiplex ligation-dependent probe amplification (MLPA). Genome-wide analyses of copy number alterations of two leptomeningeal melanocytic neoplasms were performed using the OncoScan SNP-array. GNAQ(Q209) mutations were present in eleven LMNs, while two of 20 cases carried a GNA11(Q209) mutation. No BRAF, HRAS or NRAS hotspot mutations were detected. Monosomy 3 and gain of 8q were present in one leptomeningeal melanoma, and one intermediate-grade melanocytoma harbored a gain of chromosome 6. With MLPA, the melanocytomas did not show any further gross chromosomal variations. Our data shows that primary LMNs, like uveal melanoma, harbor oncogenic mutations in GNAQ and GNA11 but lack mutations in BRAF, NRAS and HRAS. This finding may help in the differential diagnosis between a primary LMN and a metastasis from a cutaneous melanoma to the central nervous system. Copy number variations in some aggressive LMNs resemble those present in uveal melanoma but their prognostic significance is unclear.