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Molecular and histopathological analysis of melanoma subtypes has revealed distinct epidemiological, genetic, and clinical features. However, immunotherapy for advanced metastatic melanoma patients does not differ based on subtype. Response to immune checkpoint inhibitors (ICI) has been shown to vary, therefore, predictive biomarkers are needed in the design of precision treatments. Targeted sequencing and histopathological analysis (CD8 and CD20 immunohistochemistry) were performed on subtypes of metastatic melanoma (cutaneous melanoma (CM, n = 10); head and neck melanoma (HNM, n = 7); uveal melanoma (UM, n = 4); acral lentiginous melanoma (AM, n = 1) and mucosal melanoma (MM, n = 1) treated with ICI). Progression-free survival (PFS) was significantly associated with high CD8 expression (p = 0.025) and mutations in DNA damage repair (DDR) pathway genes (p = 0.012) in all subtypes but not with CD20 expression. Our study identified that immune cell infiltration and DDR gene mutations may have an impact in response to ICI treatment in metastatic melanoma but differs among subtypes. Therefore, a comprehensive understanding of the immune infiltration cells' role and DDR gene mutations in metastatic melanoma may identify prognostic biomarkers.
Assuntos
Melanoma , Segunda Neoplasia Primária , Neoplasias Cutâneas , Dano ao DNA , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Mutação , Segunda Neoplasia Primária/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/genética , Melanoma Maligno CutâneoRESUMO
The presence of contaminating non-tumor tissues in formalin-fixed paraffin-embedded (FFPE) tissues can greatly undermine genomic studies. Herein we describe macrodissection, a method designed to augment the percentage tumor content of a tissue specimen by removing and eliminating unwanted tissue prior to performing downstream nucleic acid extractions. FFPE tissue blocks were sectioned to produce 4-5 µm slide-mounted tissue sections. A representative section was submitted for hematoxylin and eosin (H&E) staining and subsequently reviewed by a board-certified pathologist. During the review, the pathologist identified and marked the regions of tumor tissue in the H&E. Once complete, the demarked H&E was used to guide resection of the serial unstained sections from the same tissue block. To demonstrate the effects of macrodissection, RNA extracted from matched macrodissected and non-dissected Diffuse Large B-Cell Lymphomas (DLBCL) were run on a digital gene expression assay capable of determining DLBCL subtype and BCL2 translocation status. The results showed that macrodissection changed the subtype or BCL2 translocation status calls in 60% of the samples examined. In conclusion, macrodissection is a simple and effective method for performing tumor enrichment prior to nucleic acid extractions, the product of which can then be confidently used in downstream genomic studies.
Assuntos
Neoplasias , Dissecação , Formaldeído , Genômica , Humanos , Inclusão em Parafina/métodos , RNA/genética , Fixação de Tecidos/métodosRESUMO
Epstein-Barr virus (EBV)-positive extranodal marginal zone lymphomas of mucosa-associated lymphoid tissue (MALT lymphomas) were initially described in solid organ transplant recipients, and, more recently, in other immunodeficiency settings. The overall prevalence of EBV-positive MALT lymphomas has not been established, and little is known with respect to their genomic characteristics. Eight EBV-positive MALT lymphomas were identified, including 1 case found after screening a series of 88 consecutive MALT lymphomas with EBER in situ hybridization (1%). The genomic landscape was assessed in 7 of the 8 cases with a targeted high throughput sequencing panel and array comparative genomic hybridization. Results were compared to published data for MALT lymphomas. Of the 8 cases, 6 occurred post-transplant, 1 in the setting of primary immunodeficiency, and 1 case was age-related. Single pathogenic/likely pathogenic mutations were identified in 4 of 7 cases, including mutations in IRF8, BRAF, TNFAIP3, and SMARCA4. Other than TNFAIP3, these genes are mutated in <3% of EBV-negative MALT lymphomas. Copy number abnormalities were identified in 6 of 7 cases with a median of 6 gains and 2 losses per case, including 4 cases with gains in regions encompassing several IRF family or interacting genes (IRF2BP2, IRF2, and IRF4). There was no evidence of trisomies of chromosomes 3 or 18. In summary, EBV-positive MALT lymphomas are rare and, like other MALT lymphomas, are usually genetically non-complex. Conversely, while EBV-negative MALT lymphomas typically show mutational abnormalities in the NF-κB pathway, other than the 1 TNFAIP3-mutated case, no other NF-κB pathway mutations were identified in the EBV-positive cases. EBV-positive MALT lymphomas often have either mutations or copy number abnormalities in IRF family or interacting genes, suggesting that this pathway may play a role in these lymphomas.
Assuntos
Infecções por Vírus Epstein-Barr , Linfoma de Zona Marginal Tipo Células B , Hibridização Genômica Comparativa , DNA Helicases/metabolismo , Infecções por Vírus Epstein-Barr/patologia , Genômica , Herpesvirus Humano 4/genética , Humanos , Tecido Linfoide/patologia , Linfoma de Zona Marginal Tipo Células B/genética , Linfoma de Zona Marginal Tipo Células B/patologia , Mucosa/patologia , NF-kappa B/genética , Proteínas Nucleares/genética , Fatores de Transcrição/genéticaRESUMO
Background: Formalin-fixed, paraffin-embedded (FFPE) tissues are a valuable resource for clinical and basic science research. Paraffin blocks and the resulting unstained sections (USS) are often stored for years before being used. Previous studies have evaluated the effects of time, temperature, humidity, and inert gases on preservation of USS; however, no study has examined all four variables together. Methods: In the current work, we prospectively and blindly assessed time points from 0 to 24 months, room versus refrigerated temperature, and presence of a desiccant and/or nitrogen atmosphere on a variety of benign and malignant tissues from North America and Africa. End points included immunohistochemistry (IHC), in situ hybridization (ISH), extracted RNA and DNA quantity and quality, and messenger RNA performance in a novel, multiplexed digital gene expression profiling assay of both housekeeping and tumor-specific genes. Results: We found that using current methods of antigen retrieval, staining, and extraction, the end points of IHC, ISH, RNA, and DNA were well preserved under the various conditions tested, with implications that pre-embedding factors contribute to variability in subsequent tissue integrity. We also document that spectrophotometric estimations of nucleic acid concentrations were in general estimated to be higher than with fluorimetric methods, which may be pertinent to end assay development. We further describe a new multiplex assay, the PlexSet digital gene expression assay, suitable for evaluating RNA quality in FFPE tissues. Conclusion: Altogether, these results may provide helpful guidance with regard to approaches for long-term storage conditions for USS.
Assuntos
Bancos de Espécimes Biológicos , RNA , Humanos , Fixação de Tecidos/métodos , Proteínas , Perfilação da Expressão Gênica , DNA , Inclusão em Parafina/métodos , FormaldeídoRESUMO
Even in the era of highly active combination antiretroviral therapy (cART), patients with HIV have a disproportionate risk of developing aggressive lymphomas that are frequently Epstein-Barr virus (EBV)-related. Here, we investigate HIV-associated diffuse large B-cell lymphoma (HIV-DLBCL) and compare EBV-positive and EBV-negative cases. HIV-DLBCL were identified from two academic medical centres and characterised by immunohistochemistry, EBV status, fluorescence in situ hybridisation, cell of origin determination by gene expression profiling, and targeted deep sequencing using a custom mutation panel of 334 genes. We also applied the Lymphgen tool to determine the genetic subtype of each case. Thirty HIV-DLBCL were identified, with a median patient age of 46 years and male predominance (5:1). Thirteen cases (48%) were EBV-positive and 14 (52%) EBV-negative. Nine of the 16 tested cases (56%) had MYC rearrangement, three (19%) had BCL6 (two of which were double hit MYC/BCL6) and none had BCL2 rearrangements. Using the Lymphgen tool, half of the cases (15) were classified as other. All HIV-DLBCL showed mutational abnormalities, the most frequent being TP53 (37%), MYC (30%), STAT3 (27%), HIST1H1E (23%), EP300 (20%), TET2 (20%), SOCS1 (17%) and SGK1 (17%). EBV-negative cases were mostly of germinal centre B-cell (GCB) origin (62%), showed more frequent mutations per case (a median of 13·5/case) and significant enrichment of TP53 (57% vs. 15%; P = 0·046), SGK1 (36% vs. 0%; P = 0·04), EP300 (43% vs. 0%; P = 0·02) and histone-modifying gene (e.g. HIST1H1E, HIST1H1D, 79% vs. 31%; P = 0·02) mutations. EBV-positive cases were mostly of non-GCB origin (70%), with fewer mutations per case (median 8/case; P = 0·007), and these tumours were enriched for STAT3 mutations (P = 0·10). EBV-positive cases had a higher frequency of MYC mutations but the difference was not significant (36% vs. 15%; P = 0·38). EBV-association was more frequent in HIV-DLBCLs, arising in patients with lower CD4 counts at diagnosis (median 46·5 vs. 101, P = 0·018). In the era of cART, approximately half of HIV-DLBCL are EBV-related. HIV-DLBCL are enriched for MYC rearrangements, MYC mutations and generally lack BCL2 rearrangements, regardless of EBV status. Among HIV-DLBCL, tumours that are EBV-negative and EBV-positive appear to have important differences, the latter arising in context of lower CD4 count, showing frequent non-GCB origin, lower mutation burden and recurrent STAT3 mutations.
Assuntos
Infecções por Vírus Epstein-Barr/complicações , Infecções por HIV/complicações , Janus Quinases/genética , Linfoma Difuso de Grandes Células B/virologia , Fatores de Transcrição STAT/genética , Adulto , Infecções por Vírus Epstein-Barr/genética , Infecções por Vírus Epstein-Barr/metabolismo , Feminino , Infecções por HIV/genética , Infecções por HIV/metabolismo , Herpesvirus Humano 4/isolamento & purificação , Humanos , Janus Quinases/metabolismo , Linfoma Difuso de Grandes Células B/etiologia , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/metabolismo , Masculino , Pessoa de Meia-Idade , Mutação , Fatores de Transcrição STAT/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de SinaisRESUMO
Mantle cell lymphoma (MCL) is a clinically heterogeneous B cell malignancy for which a variety of prognostic factors have been proposed. Previously, a digital gene expression profiling "proliferation signature" capable of risk stratifying MCL was identified and subsequently developed into a multi-analyte prognostic assay, known as the "MCL35" assay. In this study, we sought to explore the performance characteristics of the MCL35 assay in a clinical laboratory and compare results with the Ki67 proliferation marker. The results describe the clinical validation of the MCL35 assay for molecular risk stratification of MCL including accuracy, sensitivity, specificity, use in acid-decalcified bone marrow core biopsies, fixatives, lower limit of RNA input, quality metrics, and other laboratory parameters. The resulting data indicate that this is a robust technique with outstanding reproducibility. Overall, the data support the concept of molecular signatures, as assessed with digital gene expression profiling, for improved standardization and reproducibility for proliferation assessment in MCL.
RESUMO
OBJECTIVE: The increased risk for persons living with HIV to develop diffuse large B-cell lymphoma (DLBCL) even in the post-antiretroviral therapy eras suggests a role beyond immunosuppression in lymphoma development. However, the mechanisms leading to lymphoma in the HIV setting are not fully understood. HIV is known to induce activation-induced cytidine deaminase (AID) levels in nonneoplastic B cells in vitro and chronic AID expression may play an important role in lymphomagenesis. Although AID expression is observed in B-cell lymphoma, studies in HIV-associated DLBCL are limited. DESIGN: In this study, we conducted a retrospective review of DLBCL tissues from patients with and without HIV infection to compare expression of AID and B-cell receptors potentially involved in HIV and B-cell interaction. METHODS: We evaluated DLBCL formalin-fixed paraffin-embedded tissues from 72 HIV-seropositive and 58 HIV-seronegative patients for AID, DC-SIGN, and CD40 protein expression. BCL2 and MYC, two well established prognostically significant oncoproteins in DLBCL, were also assessed at the protein and mRNA levels. Subset analysis was performed according to DLBCL subtype and EBV status. RESULTS: Of note, AID expression was more frequent in HIV-associated DLBCL compared with non-HIV-associated DLBCL regardless of cell-of-origin subtype, and also displayed significantly less BCL2 expression. Despite no direct correlation with AID expression, the HIV-DLBCL tissues also exhibited high levels of the DC-SIGN receptor. CONCLUSION: Collectively, these findings support a potential role for AID in the pathogenesis of HIV-associated lymphomas and suggest the need of further investigations into the involvement of the DC-SIGN receptor-signaling pathway.
Assuntos
Biomarcadores Tumorais/análise , Citidina Desaminase/metabolismo , Infecções por HIV/complicações , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/análise , Linfócitos B , Moléculas de Adesão Celular , Citidina Desaminase/genética , Genes myc , Soronegatividade para HIV/fisiologia , Soropositividade para HIV/sangue , Humanos , Lectinas Tipo C , Linfoma de Células B/genética , Linfoma Difuso de Grandes Células B/genética , RNA Mensageiro , Receptores de Superfície Celular , Estudos Retrospectivos , Fator 3 Associado a Receptor de TNFRESUMO
Trastuzumab has significantly improved the overall survival of patients with HER2+ metastatic breast cancer (MBC). However, outcomes can vary, with patients progressing within 1 year of treatment or exceptional cases of complete response to trastuzumab for ≥10 years. Identification of the underlying genomic aberrations of "exceptional responders (ExRs)" compared to "rapid non-responders (NRs)" increases our understanding of the mechanisms involved in MBC progression and identification of biomarkers of trastuzumab response and resistance. Whole-exome sequencing was performed on six ExRs compared to five NR. The overall fraction of genome copy number alteration (CNA) burden was higher in NR patients (P = 0.07), while more significantly pronounced in copy number gains (P = 0.03) in NR compared to ExRs. Delineation of the distribution of CNA burden across the genome identified a greater degree of CNA burden in NR within Chr8 (P = 0.02) and in Chr17 (P = 0.06) and conferred a statistically significant benefit in overall survival. Clinical trial number: NCT01722890 [ICORG 12/09].
Assuntos
Neoplasias da Mama/tratamento farmacológico , Sequenciamento do Exoma/métodos , Receptor ErbB-2/análise , Trastuzumab/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Variações do Número de Cópias de DNA , Feminino , Humanos , Metástase Neoplásica , Estudos RetrospectivosRESUMO
Tissue microarrays (TMAs) are important tools to conserve precious tissue resources from increasingly smaller biopsies and to control experimental costs and variation across sample sets. The quality assurance assessment of TMA materials created at centralized biobanks has not been standardized. Herein, we outline 2 processes for the construction of TMAs ("recipient block" and "tape" methods) and the associated preconstruction quality control measures (pathology review, protein and RNA assessment, map creation, and storage conditions) developed by the AIDS Cancer Specimen Resource (ACSR) Network's Science and Technology Core. These steps provide a suggested framework for quality assessment that allows end-users, receiving materials from tissue banks, confidence in their experimental results.
Assuntos
Inclusão em Parafina , Controle de Qualidade , Análise Serial de Tecidos , Humanos , Análise Serial de Tecidos/métodos , Análise Serial de Tecidos/normasRESUMO
Pediatric large B-cell lymphomas (LBCLs) share morphological and phenotypic features with adult types but have better prognosis. The higher frequency of some subtypes such as LBCL with IRF4 rearrangement (LBCL-IRF4) in children suggests that some age-related biological differences may exist. To characterize the genetic and molecular heterogeneity of these tumors, we studied 31 diffuse LBCLs (DLBCLs), not otherwise specified (NOS); 20 LBCL-IRF4 cases; and 12 cases of high-grade B-cell lymphoma (HGBCL), NOS in patients ≤25 years using an integrated approach, including targeted gene sequencing, copy-number arrays, and gene expression profiling. Each subgroup displayed different molecular profiles. LBCL-IRF4 had frequent mutations in IRF4 and NF-κB pathway genes (CARD11, CD79B, and MYD88), losses of 17p13 and gains of chromosome 7, 11q12.3-q25, whereas DLBCL, NOS was predominantly of germinal center B-cell (GCB) subtype and carried gene mutations similar to the adult counterpart (eg, SOCS1 and KMT2D), gains of 2p16/REL, and losses of 19p13/CD70. A subset of HGBCL, NOS displayed recurrent alterations of Burkitt lymphoma-related genes such as MYC, ID3, and DDX3X and homozygous deletions of 9p21/CDKN2A, whereas other cases were genetically closer to GCB DLBCL. Factors related to unfavorable outcome were age >18 years; activated B-cell (ABC) DLBCL profile, HGBCL, NOS, high genetic complexity, 1q21-q44 gains, 2p16/REL gains/amplifications, 19p13/CD70 homozygous deletions, and TP53 and MYC mutations. In conclusion, these findings further unravel the molecular heterogeneity of pediatric and young adult LBCL, improve the classification of this group of tumors, and provide new parameters for risk stratification.
Assuntos
Fatores Reguladores de Interferon/genética , Linfoma Difuso de Grandes Células B/genética , Mutação , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/patologia , Masculino , Prognóstico , Transcriptoma , Adulto JovemAssuntos
Biomarcadores Tumorais/genética , Neoplasias do Sistema Nervoso Central/patologia , Perfilação da Expressão Gênica , Infecções por HIV/virologia , Linfoma não Hodgkin/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/genética , Terapia Combinada , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , HIV/isolamento & purificação , Humanos , Linfoma não Hodgkin/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
Diffuse large B-cell lymphoma (DLBCL) is up to 17-fold more likely to occur, follows a more aggressive clinical course and frequently presents at advanced stages in HIV infected (+) individuals compared to HIV negative (-) individuals. However, the molecular pathology underpinning the clinical features of DLBCL in HIV(+) patients relative to the general population is poorly understood. We performed a retrospective study examining the transcriptional, genomic and protein expression differences between HIV(+) and HIV(-) germinal center B-cell (GCB) DLBCL cases using digital gene expression analysis, array comparative genomic hybridization (CGH) and immunohistochemistry (IHC). Genes associated with cell cycle progression (CCNA2, CCNB1, CDC25A, E2F1), DNA replication (MCM2, MCM4, MCM7) and DNA damage repair, including eight Fanconi anemia genes (FANCA, FANCD1/BRCA2, FANCE, FANCG, FANCR/RAD51, FANCS/BRCA1, FANCT/UBE2T, FANCV/MAD2L2), were significantly increased in HIV(+) GCB-DLBCL tumors compared to HIV(-) tumors. In contrast, genes associated with cell cycle inhibition (CDKN1A, CDKN1B) as well as apoptosis regulating BCL2 family members (BCL2, BAX, BIM, BMF, PUMA) were significantly decreased in the HIV(+) cohort. BCL2 IHC confirmed this expression. Array CGH data revealed that HIV(+) GCB-DLBCL tumors have fewer copy number variations than their HIV(-) counterparts, indicating enhanced genomic stability. Together, the results show that HIV(+) GCB-DLBCL is a distinct molecular malignancy from HIV(-) GCB-DLBCL; with an increased proliferative capacity, confirmed by Ki67 IHC staining, and enhanced genomic stability, the latter of which is likely related to the enhanced expression of DNA repair genes.
Assuntos
Reparo do DNA , Perfilação da Expressão Gênica/métodos , Instabilidade Genômica , Infecções por HIV/genética , Linfoma Difuso de Grandes Células B/genética , Adulto , Idoso , Hibridização Genômica Comparativa , Feminino , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Imuno-Histoquímica , Linfoma Difuso de Grandes Células B/virologia , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
Molecular profiling of lymphoma samples has contributed enormously to our understanding of disease biology leading to detailed descriptions of diagnostic categories. These studies have also helped the field to recognize different subtypes of disease, different diseases that share similar cellular pathway perturbations, different immune responses, and different prognostic groups. While nearly all of these discoveries were made using unfixed, snap-frozen materials, with few exceptions, clinical biopsy materials are comprised of formalin-fixed and paraffin-embedded (FFPE) tissues. Here, we describe the impact of molecular profiling on the field of lymphoma, the challenges associated with using FFPE tissues for downstream molecular diagnostic testing, the various molecular profiling techniques, and also provide an example of the clinical application of a molecular profiling test of lymphoma using FFPE tissues.
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Linfoma/patologia , Inclusão em Parafina/métodos , Fixação de Tecidos/métodos , HumanosRESUMO
PURPOSE: The objective of this study was to investigate whether cell culture medium is a biologically relevant exposure medium that can be employed in non-ionising photobiological investigations. METHODS: The effect of solar-simulated irradiation on cell culture medium and its ability to elicit cell death was studied. The role of reactive oxygen species (ROS), cell secreted factors, and the contribution of individual components of the medium were investigated. RESULTS: Cell death was found to be primarily mediated through the formation of ROS via riboflavin photosensitisation and degradation in the cell culture medium. Phenol red was found to significantly reduce the cell killing ability of riboflavin. Exposures in riboflavin-free medium resulted in significantly increased cell survival compared to identical exposures in riboflavin containing medium. CONCLUSIONS: This study has shown that solar radiation toxicity is augmented by cell culture medium due to the presence of riboflavin. Results suggest that exposures performed in phenol red-free medium may serve to increase phototoxic effects if riboflavin is present. Riboflavin-free media is recommended for solar radiation investigations to eliminate concerns regarding riboflavin photosensitisation and nutrient deprivation.
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Morte Celular/efeitos da radiação , Queratinócitos/efeitos da radiação , Luz Solar/efeitos adversos , Antioxidantes/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos da radiação , Ensaio de Unidades Formadoras de Colônias , Meios de Cultura/química , Meios de Cultura/efeitos da radiação , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Fenolsulfonaftaleína/química , Fenolsulfonaftaleína/efeitos da radiação , Fármacos Fotossensibilizantes/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Riboflavina/metabolismo , Riboflavina/efeitos da radiação , EspectrofotometriaRESUMO
Photo-biological investigations are dependent on calibration and characterisation to determine the relevance of an artificial irradiator to the study at hand. The importance of this has been voiced in the literature. However, the importance of output delivery is relatively unknown. The biological relevance of a high-energy, rapidly pulsing solar simulator was investigated using the clonogenic assay and was found to be reciprocity law compliant despite an exaggerated ultraviolet (UV) irradiance in excess of 1600 W m(-2) delivered per pulse. In fact, it was found to be the least cytotoxic irradiator compared with a second solar simulator and a UVB fluorescent lamp with continuous UV irradiances of 55 and 6.4 W m(-2), respectively. The reduced survival observed with the continuous irradiators is attributed to differences in spectral irradiance and distribution, particularly in the UVB, which in the absence of thorough calibration and characterisation may have resulted in erroneous conclusions.