RESUMO
BACKGROUND: Cell-free DNA (cfDNA) profiles of 5-hydroxymethylcytosine (5-hmC), an epigenetic marker of open chromatin and active gene expression, are correlated with metastatic disease burden in patients with neuroblastoma. Neuroblastoma tumors are comprised of adrenergic (ADRN) and mesenchymal (MES) cells, and the relative abundance of each in tumor biopsies has prognostic implications. We hypothesized that ADRN and MES-specific signatures could be quantified in cfDNA 5-hmC profiles and would augment the detection of metastatic burden in patients with neuroblastoma. METHODS: We previously performed an integrative analysis to identify ADRN and MES-specific genes (n = 373 and n = 159, respectively). Purified DNA from cell lines was serial diluted with healthy donor cfDNA. Using Gene Set Variation Analysis (GSVA), ADRN and MES signatures were optimized. We then quantified signature scores, and our prior neuroblastoma signature, in cfDNA from 84 samples from 46 high-risk patients including 21 patients with serial samples. RESULTS: Samples from patients with higher metastatic burden had increased GSVA scores for both ADRN and MES gene signatures (p < .001). While ADRN and MES signature scores tracked together in serially collected samples, we identified instances of patients with increases in either MES or ADRN score at relapse. CONCLUSIONS: While it is feasible to identify ADRN and MES signatures using 5-hmC profiles of cfDNA from neuroblastoma patients and correlate these signatures to metastatic burden, additional data are needed to determine the optimal strategies for clinical implementation. Prospective evaluation in larger cohorts is ongoing.
Assuntos
Ácidos Nucleicos Livres , Segunda Neoplasia Primária , Neuroblastoma , Humanos , Criança , Ácidos Nucleicos Livres/genética , Recidiva Local de Neoplasia , Neuroblastoma/patologia , PrognósticoRESUMO
BACKGROUND: Array comparative genomic hybridization (CGH) analyses of frozen tumors have shown strong associations between the pattern of chromosomal aberrations and outcome in patients with advanced-stage neuroblastoma. New platforms for analyzing chromosomal aberrations using formalin-fixed paraffin-embedded (FFPE) tissue have recently been developed. We sought to determine whether chromosomal microarray analysis (CMA) using FFPE tumors is feasible and if segmental chromosomal aberrations were prognostic of recurrence in localized neuroblastoma. METHODS: Patients with MYCN nonamplified International Neuroblastoma Staging System stage 1 and 2 disease who recurred were identified. CMA was performed with diagnostic FFPE samples using OncoScan™ FFPE Express 2.0. The prognostic significance of chromosomal pattern was validated in 105 patients with available CGH results. RESULTS: In 26 evaluable patients, 11 recurred locally, nine had metastatic relapse, and six remained progression free >3 years from diagnosis. No chromosomal aberrations were identified in four tumors. Numerical chromosomal aberrations (NCAs) without segmental chromosomal aberration (SCA) were identified in 11 patients: six progressed locally, two had metastatic progression and 3 remained progression-free. Eleven patients had SCAs: four progressed locally, six developed metastatic progression and one remained progression-free. Five or more SCAs were only detected in tumors from patients who developed metastases (P = 0.0004). In the validation cohort, SCAs were associated with inferior event-free survival (EFS) compared to NCA (5-year EFS 68% ± 8.3% vs. 91% ± 3.6%, respectively; P = 0.0083). CONCLUSIONS: It is feasible to evaluate chromosomal aberrations using FFPE neuroblastoma tissue. SCA is associated with inferior EFS in localized neuroblastoma patients, and multiple SCAs may be predictive of metastatic relapse.
Assuntos
Formaldeído , Neuroblastoma/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Inclusão em Parafina , Fixação de Tecidos , Criança , Pré-Escolar , Aberrações Cromossômicas , Intervalo Livre de Doença , Feminino , Humanos , Lactente , Recém-Nascido , Estimativa de Kaplan-Meier , Masculino , Neuroblastoma/mortalidadeRESUMO
PURPOSE: Neuroblastoma is the most common extracranial solid tumor in childhood. We previously showed that circulating cell-free DNA (cfDNA) and tumor biopsy derived 5-hydroxymethylcytosime (5-hmC) profiles identified patients with neuroblastoma who experienced subsequent relapse. Here, we hypothesized that 5-hmC modifications selectively enriched in cfDNA compared with tumor biopsy samples would identify epigenetic changes associated with aggressive tumor behavior and identify novel biomarkers of outcome in patients with high-risk neuroblastoma. METHODS: 5-hmC profiles from cfDNA (n = 64) and tumor biopsies (n = 48) were compared. Two neuroblastoma cell lines underwent chromatin immunoprecipitation followed by sequencing (ChIP-Seq) for H3K27me3, H3K4me3, and H3K27ac; kethoxal-associated single-stranded DNA sequencing; hmC-Seal for 5-hmC; and RNA-sequencing (RNA-Seq). Genes enriched for both H3K27me3 and H3K4me3 in the included cell lines were defined as bivalent. Using bivalent genes defined in vitro, a bivalent signature was established in three publicly available cohorts of patients with neuroblastoma through gene set variation analysis. Differences between tumors with high or low bivalent signatures were assessed by the Kaplan-Meier method and Cox proportional hazards models. RESULTS: In cfDNA compared with tumor biopsy derived 5-hmC profiles, we found increased 5-hmC deposition on Polycomb Repressive Complex 2 target genes, a finding previously described in the context of bivalent genes. We identified 313 genes that bore bivalent chromatin marks, were enriched for mediators of neuronal differentiation, and were transcriptionally repressed across a panel of heterogeneous neuroblastoma cell lines. In three distinct clinical cohorts, low bivalent signature was significantly and independently associated with worse clinical outcome in patients with high-risk neuroblastoma. CONCLUSION: Low expression of bivalent genes is a biomarker of worse outcome in patients with high-risk neuroblastoma.
Assuntos
5-Metilcitosina/análogos & derivados , Ácidos Nucleicos Livres , Neuroblastoma , Humanos , Histonas/genética , Histonas/metabolismo , Prognóstico , Neuroblastoma/genéticaRESUMO
Recent insights have identified adrenergic (ADRN) and mesenchymal (MES) cell lineages as distinct biologic cell types and T-cell inflammation as a prognostic marker in neuroblastoma. We hypothesized that elucidating unique and overlapping aspects of these biologic features could serve as novel biomarkers for informing ongoing efforts to improve therapeutic approaches for children with high-risk neuroblastoma. We identified lineage-specific, single-stranded super-enhancers to define ADRN and MES specific genes. Publicly available RNA-seq of diagnostic tumor biopsies was used in Discovery and Validation cohorts. Each tumor was assigned a relative MES score and T-cell inflammation (TCI) score. Survival was assessed using the Kaplan-Meier method, and differences were assessed by the log-rank test. Inflammation scores were correlated with MES scores and anticorrelated with MYCN-amplification in both cohorts. Among patients with high-risk, ADRN tumors, those with TCI tumors had superior overall survival to those with non-inflamed tumors. A similar, but nonsignificant, trend was observed in the Validation cohort. Conversely, there was no difference according to TCI status in the MES cohort in either the Discover or Validation cohorts. High-inflammation scores were correlated with improved survival in some patients with high-risk, ADRN but not MES neuroblastoma. Our findings bolster support for further developing T-cell-based and immunotherapy-based approaches for children with high-risk neuroblastoma of varying MES and ADRN expression. SIGNIFICANCE: Adrenergic (ADRN) and mesenchymal (MES) lineages are distinct biologic cell types in neuroblastoma. We defined ADRN and MES specific genes and found that high-risk, ADRN tumors harboring elevated T-cell inflammation signatures had superior overall survival. Our findings bolster support for further developing immunotherapy-based approaches for children with high-risk neuroblastoma.
Assuntos
Inflamação , Neuroblastoma , Linfócitos T , Humanos , Neuroblastoma/mortalidade , Neuroblastoma/patologia , Neuroblastoma/imunologia , Neuroblastoma/genética , Inflamação/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Prognóstico , Masculino , Feminino , Pré-Escolar , Biomarcadores Tumorais/genética , Lactente , Criança , Regulação Neoplásica da Expressão GênicaRESUMO
The N6-methyladenosine (m6A) RNA modification is an important regulator of gene expression. m6A is deposited by a methyltransferase complex that includes methyltransferase-like 3 (METTL3) and methyltransferase-like 14 (METTL14). High levels of METTL3/METTL14 drive the growth of many types of adult cancer, and METTL3/METTL14 inhibitors are emerging as new anticancer agents. However, little is known about the m6A epitranscriptome or the role of the METTL3/METTL14 complex in neuroblastoma, a common pediatric cancer. Here, we show that METTL3 knockdown or pharmacologic inhibition with the small molecule STM2457 leads to reduced neuroblastoma cell proliferation and increased differentiation. These changes in neuroblastoma phenotype are associated with decreased m6A deposition on transcripts involved in nervous system development and neuronal differentiation, with increased stability of target mRNAs. In preclinical studies, STM2457 treatment suppresses the growth of neuroblastoma tumors in vivo. Together, these results support the potential of METTL3/METTL14 complex inhibition as a therapeutic strategy against neuroblastoma.
Assuntos
Diferenciação Celular , Proliferação de Células , Metiltransferases , Neuroblastoma , Metiltransferases/metabolismo , Metiltransferases/antagonistas & inibidores , Neuroblastoma/patologia , Neuroblastoma/metabolismo , Neuroblastoma/tratamento farmacológico , Neuroblastoma/genética , Humanos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Animais , Camundongos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Adenosina/análogos & derivados , Adenosina/metabolismo , Adenosina/farmacologiaRESUMO
Neuroblastoma (NB), a childhood neoplasm arising from neural crest cells, is characterized by a diversity of clinical behaviors ranging from spontaneous remission to rapid tumor progression and death. In addition to genetic abnormalities, recent studies have indicated that epigenetic aberrations also contribute toward NB pathogenesis. However, the epigenetic mechanisms underlying the pathogenesis of NB are largely unknown. Inhibition of euchromatic histone-lysine N-methyltransferase 2 (EHMT2) was evaluated through the measurement of H3K9Me2 levels. Cell proliferation was examined by cell counting in human NB cell lines (LA1-55n, IMR-5, and NMB). The RNA expression of EHMT2, MYCN, and p21 was measured by real-time PCR. The expression of PCNA, MYCN, p53, cyclinD1, H3, H3K27M2, and H3K9Me2 was examined by western blot analysis. In-vitro invasion and the effects of the EHMT2 inhibitor (BIX-01294) were assessed in the Transwell chamber assay. Caspase 3 and 8 activities were measured using a Caspase-Glo assay kit. The level of overall DNA methylation was measured by liquid chromatography-mass spectroscopy. BIX-01294, a specific inhibitor of EHMT2 (a key enzyme for histone H3 dimethylation at lysine-9), specifically decreases the overall H3K9Me2 level but not H3K27Me2. The inhibition of EHMT2 decreased the proliferation of NB cells and induced apoptosis by increasing caspase 8/caspase 3 activity. BIX-01294 inhibited NB cell mobility and invasion. This was accompanied by a decreased expression of the MYCN oncogene. Inhibition of EHMT2 enhanced a doxorubicin-induced inhibitory effect on cell proliferation. Finally, EHMT2 inhibition modulated overall DNA methylation levels in NB cells. Our results show that histone-lysine methylation is involved in cell proliferation, apoptosis, cell invasion, and overall DNA methylation in human NB cells. Further understanding of this mechanism may provide an insight into the pathogenesis of NB progression and lead to novel treatment strategies.
Assuntos
Metilação de DNA , Antígenos de Histocompatibilidade/metabolismo , Histona-Lisina N-Metiltransferase/metabolismo , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Apoptose/genética , Azepinas/farmacologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ciclina D1/metabolismo , Metilação de DNA/efeitos dos fármacos , Doxorrubicina/farmacologia , Inibidores Enzimáticos/farmacologia , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Antígenos de Histocompatibilidade/genética , Histona-Lisina N-Metiltransferase/antagonistas & inibidores , Histona-Lisina N-Metiltransferase/genética , Humanos , Proteína Proto-Oncogênica N-Myc , Neuroblastoma/tratamento farmacológico , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Quinazolinas/farmacologiaRESUMO
Background: Cell free DNA (cfDNA) profiles of 5-hydroxymethylcytosine (5-hmC), an epigenetic marker of open chromatin and active gene expression, are correlated with metastatic disease burden in patients with neuroblastoma. Neuroblastoma tumors are comprised of adrenergic (ADRN) and mesenchymal (MES) cells, and the relative abundance of each in tumor biopsies has prognostic implications. We hypothesized that ADRN and MES specific signatures could be quantified in cfDNA 5-hmC profiles and would augment the detection of metastatic burden in patients with neuroblastoma. Methods: We previously performed an integrative analysis to identify ADRN and MES specific genes (n=373 and n=159, respectively). Purified DNA from cell lines was serial diluted with healthy donor cfDNA. Using Gene Set Variation Analysis (GSVA), ADRN and MES signatures were optimized. We then quantified signature scores, and our prior neuroblastoma signature, in cfDNA from 84 samples from 46 high-risk patients including 21 patients with serial samples. Results: Samples from patients with higher metastatic burden had increased GSVA scores for both ADRN and MES gene signatures (p < 0.001). While ADRN and MES signature scores tracked together in serially collected samples, we identified instances of patients with increases in either MES or ADRN score at relapse. Conclusions: While it is feasible to identify ADRN and MES signatures using 5-hmC profiles of cfDNA from neuroblastoma patients and correlate these signatures to metastatic burden, additional data are needed to determine the optimal strategies for clinical implementation. Prospective evaluation in larger cohorts is ongoing.
RESUMO
Neuroblastoma is the most common extra-cranial solid tumor in childhood and epigenetic dysregulation is a key driver of this embryonal disease. In cell-free DNA from neuroblastoma patients with high-risk disease, we found increased 5-hydroxymethylcytosine (5-hmC) deposition on Polycomb Repressive Complex 2 (PRC2) target genes, a finding previously described in the context of bivalent genes. As bivalent genes, defined as genes bearing both activating (H3K4me3) and repressive (H3K27me3) chromatin modifications, have been shown to play an important role in development and cancer, we investigated the potential role of bivalent genes in maintaining a de-differentiated state in neuroblastoma and their potential use as a biomarker. We identified 313 genes that bore bivalent chromatin marks, were enriched for mediators of neuronal differentiation, and were transcriptionally repressed across a panel of heterogenous neuroblastoma cell lines. Through gene set variance analysis, we developed a clinically implementable bivalent signature. In three distinct clinical cohorts, low bivalent signature was significantly and independently associated with worse clinical outcome in high-risk neuroblastoma patients. Thus, low expression of bivalent genes is a biomarker of ultra-high-risk disease and may represent a therapeutic opportunity in neuroblastoma.
RESUMO
Purpose: T-cell inflammation (TCI) has been shown to be a prognostic marker in neuroblastoma, a tumor comprised of cells that can exist in two epigenetic states, adrenergic (ADRN) and mesenchymal (MES). We hypothesized that elucidating unique and overlapping aspects of these biologic features could serve as novel biomarkers. Patients and Methods: We detected lineage-specific, single-stranded super-enhancers defining ADRN and MES specific genes. Publicly available neuroblastoma RNA-seq data from GSE49711 (Cohort 1) and TARGET (Cohort 2) were assigned MES, ADRN, and TCI scores. Tumors were characterized as MES (top 33%) or ADRN (bottom 33%), and TCI (top 67% TCI score) or non-inflamed (bottom 33% TCI score). Overall survival (OS) was assessed using the Kaplan-Meier method, and differences were assessed by the log-rank test. Results: We identified 159 MES genes and 373 ADRN genes. TCI scores were correlated with MES scores (R=0.56, p<0.001 and R=0.38, p<0.001) and anticorrelated with MYCN -amplification (R=-0.29, p<0.001 and -0.18, p=0.03) in both cohorts. Among Cohort 1 patients with high-risk, ADRN tumors (n=59), those with TCI tumors (n=22) had superior OS to those with non-inflammed tumors (n=37) (p=0.01), though this comparison did not reach significance in Cohort 2. TCI status was not associated with survival in patients with high-risk MES tumors in either cohort. Conclusions: High inflammation scores were correlated with improved survival in some high-risk patients with, ADRN but not MES neuroblastoma. These findings have implications for approaches to treating high-risk neuroblastoma.
RESUMO
SPARC is a matricellular glycoprotein that mediates interactions between cells and their microenvironment. It is produced at sites of tissue remodeling, where it regulates matrix deposition and turnover, cell adhesion, and signaling by extracellular factors, exerting profound effects on tissue architecture and cell physiology. During extensive matrix remodeling in neoplastic progression, SPARC is expressed in cancer-associated stroma and in malignant cells of some types, affecting tumor development, invasion, metastases, angiogenesis and inflammation. SPARC-induced changes in the tumor microenvironment can suppress or promote progression of different cancers depending on the tissue and cell type. Understanding the mechanism of matrix remodeling and its regulation by SPARC is essential for the development of new treatment strategies for highly aggressive cancers.
Assuntos
Matriz Extracelular/metabolismo , Neoplasias , Osteonectina/metabolismo , Sequência de Aminoácidos , Animais , Transformação Celular Neoplásica , Modelos Animais de Doenças , Progressão da Doença , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Dados de Sequência Molecular , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/fisiopatologia , Osteonectina/genética , Receptores de Superfície Celular/metabolismo , Alinhamento de Sequência , Transdução de Sinais/fisiologia , Células Estromais/metabolismo , Células Estromais/patologiaRESUMO
Epigenetic aberrations and a CpG island methylator phenotype are associated with poor outcome in children with neuroblastoma (NB). Previously, we have shown that valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, exerts antitumor effects in an NB xenograft model. However, the underlying antitumor molecular mechanisms are largely unknown. In this study, we examined the role of HDAC in cell proliferation, cell cycle progression, gene expression patterns, and epigenome in NB. Cell proliferation, cell cycle progression, caspase activity, RNA and protein expression, quantitative methylation, and global DNA methylation were examined in NBL-W-N and LA1-55n NB cell lines. Our studies showed that inhibition of HDAC decreased NB proliferation, and induced caspase activity and G1 growth arrest. Expression patterns of cancer-related genes were modulated by VPA. The expression of THBS1, CASP8, SPARC, CDKN1A, HIC1, CDKN1B, and HIN1 was upregulated, and that of MYCN and TIG1 was downregulated. HDAC inhibition decreased methylation levels of THBS1 and RASSF1A promoters. Inhibition of HDAC increased acetylation of histone 4 and overall DNA methylation levels. Our studies showed that inhibition of HDAC blocked cell proliferation and cell cycle progression in relation to alteration in cancer-related genes, increased overall DNA methylation, and decreased methylation of tumor suppressor genes. Further studies examining the antitumor effects of VPA in NB are warranted.
Assuntos
Antineoplásicos/farmacologia , Metilação de DNA/efeitos dos fármacos , Neuroblastoma/genética , Ácido Valproico/farmacologia , Acetilação/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fase G1/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genes Supressores de Tumor/efeitos dos fármacos , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Neuroblastoma/tratamento farmacológico , Neuroblastoma/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacosRESUMO
BACKGROUND: More effective therapy for children with high-risk neuroblastoma is desperately needed. Preclinical studies have shown that neuroblastoma tumor growth can be inhibited by agents that block angiogenesis. We hypothesized that drugs which target both neuroblastoma cells and tumor angiogenesis would have potent anti-tumor activity. In this study we tested the effects of sorafenib, a multi-kinase inhibitor, on neuroblastoma cell proliferation and signaling, and in mice with subcutaneous human neuroblastoma xenografts or orthotopic adrenal tumors. PROCEDURE: Mice with subcutaneous neuroblastoma xenografts or orthotopic adrenal tumors were treated with sorafenib, and tumor growth rates were measured. Blood vessel architecture and vascular density were evaluated histologically in treated and control neuroblastoma tumors. The in vitro effects of sorafenib on neuroblastoma proliferation, cell cycle, and signaling were also evaluated. RESULTS: Sorafenib inhibited tumor growth in mice with subcutaneous and orthotopic adrenal tumors. Decreased numbers of cycling neuroblastoma cells and tumor blood vessels were seen in treated versus control tumors, and the blood vessels in the treated tumors had more normal architecture. Sorafenib treatment also decreased neuroblastoma cell proliferation, attenuated ERK signaling, and enhanced G(1) /G(0) cell cycle arrest in vitro. CONCLUSIONS: Our results demonstrate that sorafenib inhibits the growth of neuroblastoma tumors by targeting both neuroblastoma cells and tumor blood vessels. Single agent sorafenib should be evaluated in future phase II neuroblastoma studies.
Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Benzenossulfonatos/farmacologia , Proliferação de Células/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neuroblastoma/patologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , Animais , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neovascularização Patológica/patologia , Neuroblastoma/irrigação sanguínea , Neuroblastoma/fisiopatologia , Niacinamida/análogos & derivados , Compostos de Fenilureia , SorafenibeRESUMO
Tumors depend upon angiogenesis for growth and metastasis. It is therefore critical to understand the inhibitory signaling mechanisms in endothelial cells that control angiogenesis. Epac is a cyclic adenosine 5'-monophosphate-activated guanine nucleotide exchange factor for Rap1. In this study, we show that activation of Epac or Rap1 leads to potent inhibition of angiogenesis in vivo. Epac/Rap1 activation down-regulates inhibitor of differentiation 1 (Id1), which negatively regulates thrombospondin-1 (TSP1), an inhibitor of angiogenesis. Consistent with this mechanism, activation of Epac/Rap 1 induces expression of TSP1; conversely, depletion of Epac reduces TSP1 levels in endothelial cells. Blockade of TSP1 binding to its receptor, CD36, rescues inhibition of chemotaxis or angiogenesis by activated Epac/Rap1. Mitogen-activated protein kinase kinase 5, a downstream mediator of vascular endothelial growth factor, antagonizes the effects of Epac/Rap1 by inducing Id1 and suppressing TSP1 expression. Finally, TSP1 is also secreted by fibroblasts in response to Epac/Rap1 activation. These results identify Epac and Rap1 as inhibitory regulators of the angiogenic process, implicate Id1 and TSP1 as downstream mediators of Epac/Rap1, and highlight a novel interplay between pro- and antiangiogenic signaling cascades involving multiple cell types within the angiogenic microenvironment.
Assuntos
Fatores de Troca do Nucleotídeo Guanina/metabolismo , MAP Quinase Quinase 5/metabolismo , Proteína Quinase 7 Ativada por Mitógeno/metabolismo , Neovascularização Patológica/metabolismo , Trombospondinas/metabolismo , Proteínas rap1 de Ligação ao GTP/metabolismo , Animais , Western Blotting , Células Endoteliais/metabolismo , Humanos , Proteína 1 Inibidora de Diferenciação/metabolismo , Camundongos , Camundongos Nus , Transdução de Sinais/fisiologia , TransfecçãoRESUMO
The quinoxaline anti-tumor agent (R+)XK469 mediates its effects by topoisomerase IIB inhibition. This report describes a 14-year old with relapsed neuroblastoma who experienced disease stabilization for 14 months while receiving (R+)XK469 monotherapy. Due to this favorable response, laboratory studies were undertaken to determine efficacy in the preclinical setting. (R+)XK469 inhibited proliferation, caused G(2) cell cycle arrest of neuroblastoma cells in vitro, and inhibited growth of neuroblastoma xenograft tumors. These preclinical results, coupled with the favorable clinical response, demonstrate that (R+)XK469 and similar anti-tumor agents may be effective in the treatment of high-risk neuroblastoma and warrant further testing.
Assuntos
Proliferação de Células/efeitos dos fármacos , Neuroblastoma/tratamento farmacológico , Quinoxalinas/farmacologia , Adolescente , Antineoplásicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Evolução Fatal , Humanos , Metástase Neoplásica , Neuroblastoma/patologia , Quinoxalinas/uso terapêutico , Resultado do Tratamento , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: New, more effective strategies are needed to treat highly aggressive neuroblastoma. Our laboratory has previously shown that full-length Secreted Protein Acidic and Rich in Cysteine (SPARC) and a SPARC peptide corresponding to the follistatin domain of the protein (FS-E) potently block angiogenesis and inhibit the growth of neuroblastoma tumors in preclinical models. Peptide FS-E is structurally complex and difficult to produce, limiting its potential as a therapeutic in the clinic. RESULTS: In this study, we synthesized two smaller and structurally more simple SPARC peptides, FSEN and FSEC, that respectively correspond to the N-and C-terminal loops of peptide FS-E. We show that both peptides FSEN and FSEC have anti-angiogenic activity in vitro and in vivo, although FSEC is more potent. Peptide FSEC also significantly inhibited the growth of neuroblastoma xenografts. Histologic examination demonstrated characteristic features of tumor angiogenesis with structurally abnormal, tortuous blood vessels in control neuroblastoma xenografts. In contrast, the blood vessels observed in tumors, treated with SPARC peptides, were thin walled and structurally more normal. Using a novel method to quantitatively assess blood vessel abnormality we demonstrated that both SPARC peptides induced changes in blood vessel architecture that are consistent with blood vessel normalization. CONCLUSION: Our results demonstrate that SPARC peptide FSEC has potent anti-angiogenic and anti-tumorigenic effects in neuroblastoma. Its simple structure and ease of production indicate that it may have clinical utility in the treatment of high-risk neuroblastoma and other types of pediatric and adult cancers, which depend on angiogenesis.
Assuntos
Inibidores da Angiogênese/farmacologia , Neuroblastoma/tratamento farmacológico , Osteonectina/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Progressão da Doença , Células Endoteliais/efeitos dos fármacos , Imunofluorescência , Humanos , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Neuroblastoma/irrigação sanguínea , Peptídeos , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: Epigenetic aberrations and a CpG island methylator phenotype have been shown to be associated with poor outcomes in children with neuroblastoma (NB). Seven cancer related genes (THBS-1, CASP8, HIN-1, TIG-1, BLU, SPARC, and HIC-1) that have been shown to have epigenetic changes in adult cancers and play important roles in the regulation of angiogenesis, tumor growth, and apoptosis were analyzed to investigate the role epigenetic alterations play in determining NB phenotype. METHODS: Two NB cell lines (tumorigenic LA1-55n and non-tumorigenic LA1-5s) that differ in their ability to form colonies in soft agar and tumors in nude mice were used. Quantitative RNA expression analyses were performed on seven genes in LA1-5s, LA1-55n and 5-Aza-dC treated LA1-55n NB cell lines. The methylation status around THBS-1, HIN-1, TIG-1 and CASP8 promoters was examined using methylation specific PCR. Chromatin immunoprecipitation assay was used to examine histone modifications along the THBS-1 promoter. Luciferase assay was used to determine THBS-1 promoter activity. Cell proliferation assay was used to examine the effect of 5-Aza-dC on NB cell growth. The soft agar assay was used to determine the tumorigenicity. RESULTS: Promoter methylation values for THBS-1, HIN-1, TIG-1, and CASP8 were higher in LA1-55n cells compared to LA1-5s cells. Consistent with the promoter methylation status, lower levels of gene expression were detected in the LA1-55n cells. Histone marks associated with repressive chromatin states (H3K9Me3, H3K27Me3, and H3K4Me3) were identified in the THBS-1 promoter region in the LA1-55n cells, but not the LA1-5s cells. In contrast, the three histone codes associated with an active chromatin state (acetyl H3, acetyl H4, and H3K4Me3) were present in the THBS-1 promoter region in LA1-5s cells, but not the LA1-55n cells, suggesting that an accessible chromatin structure is important for THBS-1 expression. We also show that 5-Aza-dC treatment of LA1-55n cells alters the DNA methylation status and the histone code in the THBS-1 promoter modifies cell morphology, and inhibits their ability to form colonies in soft agar. CONCLUSION: Our results suggest that epigenetic aberrations contribute to NB phenotype, and that tumorigenic properties can be inhibited by reversing the epigenetic changes with 5-Aza-dC.
Assuntos
Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Neuroblastoma/genética , Acetilação , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Forma Celular , Imunoprecipitação da Cromatina , Metilação de DNA , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/metabolismo , Decitabina , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Epigênese Genética/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Genótipo , Inibidores de Histona Desacetilases/farmacologia , Histonas/metabolismo , Humanos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Fenótipo , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Trombospondina 1/genética , Transfecção , Ácido Valproico/farmacologiaRESUMO
PURPOSE: 5-Hydroxymethylcytosine (5-hmC) is an epigenetic marker of open chromatin and active gene expression. We profiled 5-hmC with Nano-hmC-Seal technology using 10 ng of plasma-derived cell-free DNA (cfDNA) in blood samples from patients with neuroblastoma to determine its utility as a biomarker. EXPERIMENTAL DESIGN: For the Discovery cohort, 100 5-hmC profiles were generated from 34 well children and 32 patients (27 high-risk, 2 intermediate-risk, and 3 low-risk) at various time points during the course of their disease. An independent Validation cohort encompassed 5-hmC cfDNA profiles (n = 29) generated from 21 patients (20 high-risk and 1 intermediate-risk). Metastatic burden was classified as high, moderate, low, or none per Curie metaiodobenzylguanidine scores and percentage of tumor cells in bone marrow. Genes with differential 5-hmC levels between samples according to metastatic burden were identified using DESeq2. RESULTS: Hierarchical clustering using 5-hmC levels of 347 genes identified from the Discovery cohort defined four clusters of samples that were confirmed in the Validation cohort and corresponded to high, high-moderate, moderate, and low/no metastatic burden. Samples from patients with increased metastatic burden had increased 5-hmC deposition on genes in neuronal stem cell maintenance and epigenetic regulatory pathways. Further, 5-hmC cfDNA profiles generated with 1,242 neuronal pathway genes were associated with subsequent relapse in the cluster of patients with predominantly low or no metastatic burden (sensitivity 65%, specificity 75.6%). CONCLUSIONS: cfDNA 5-hmC profiles in children with neuroblastoma correlate with metastatic burden and warrants development as a biomarker of treatment response and outcome.
Assuntos
5-Metilcitosina/análogos & derivados , Biomarcadores Tumorais/análise , Ácidos Nucleicos Livres/sangue , Metilação de DNA , Epigenômica , Neuroblastoma/patologia , 5-Metilcitosina/metabolismo , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Metástase Neoplásica , Neuroblastoma/sangue , Neuroblastoma/genética , Prognóstico , Adulto JovemRESUMO
Stromal cells have a central function in the regulation of tumor angiogenesis. Recent studies have shown that stromal myofibroblasts (cancer-associated fibroblasts) actively promote tumor growth and enhance tumor angiogenesis in many types of adult carcinomas. To evaluate the function cancer-associated fibroblasts have in neuroblastoma angiogenesis and investigate their relationship to stromal Schwann cells, we quantified cancer-associated fibroblasts in 60 primary neuroblastoma tumors and in a novel neuroblastoma xenograft model in which murine Schwann cells were induced to infiltrate into the tumor stroma. Tumor sections were examined for presence of microvascular proliferation, a hallmark of tumor angiogenesis. Cancer-associated fibroblasts were characterized by positive immunostaining for alpha-smooth muscle actin (alpha-SMA) and were distinguished from pericytes by staining negatively for high-molecular-weight caldesmon. alpha-SMA-positive cells were quantified and their number was defined as high when >1.0% of the area was positive. Associations between high cancer-associated fibroblast number, microvascular proliferation and established prognosticators were analyzed. High numbers of cancer-associated fibroblasts were associated with Schwannian stroma-poor histopathology and microvascular proliferation. Thirty-seven (80%) of the 46 Schwannian stroma-poor tumors had high numbers of cancer-associated fibroblasts in the tumor stroma compared to only 2 (14%) of the 14 Schwannian stroma-rich/dominant tumors (P<0.001). Thirty-three (89%) of 37 tumors with microvascular proliferation had high numbers of cancer-associated fibroblasts compared to 9 (40%) of 22 tumors without microvascular proliferation (P<0.001). In the xenografts with infiltrating Schwann cells (n=10), the number of cancer-associated fibroblasts per mm(2) was approximately sevenfold less than in the control xenografts without stromal Schwann cells (n=9) (mean of 51+/-30 vs 368+/-105, respectively; P<0.001). Thus, cancer-associated fibroblasts were inversely associated with presence of Schwann cells, suggesting that Schwann cells may prevent the activation of fibroblasts. A deeper understanding of the function cancer-associated fibroblasts have in neuroblastoma angiogenesis may guide future development of stroma-directed therapeutic strategies.
Assuntos
Fibroblastos/patologia , Neovascularização Patológica/patologia , Neuroblastoma/patologia , Células de Schwann/patologia , Células Estromais/patologia , Actinas/metabolismo , Animais , Biomarcadores/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Feminino , Fibroblastos/metabolismo , Humanos , Lactente , Masculino , Camundongos , Camundongos Nus , Transplante de Neoplasias , Neuroblastoma/irrigação sanguínea , Neuroblastoma/mortalidade , Pericitos/metabolismo , Pericitos/patologia , Nervo Isquiático/patologia , Nervo Isquiático/cirurgiaRESUMO
In the pediatric cancer neuroblastoma, clinically aggressive disease is associated with increased levels of angiogenesis stimulators and high vascular index. We and others have hypothesized that blocking angiogenesis may be effective treatment for this pediatric malignancy. However, little is known about the efficacy of antiangiogenic agents in pediatric malignancies. Recently, promising results have been reported in an adult phase I study of ABT-510, a peptide derivative of the natural angiogenic inhibitor thrombospondin-1. Histone deacetylase inhibitors, such as valproic acid (VPA), have also been shown to have antiangiogenic activity in several cancer models. In this study, we evaluated the effects of ABT-510 and VPA on neuroblastoma tumor growth and angiogenesis. Although only VPA was capable of blocking the proliferation of neuroblastoma cells and inducing neuroblastoma cell apoptosis in vitro, treatment with VPA or ABT-510 alone significantly suppressed the growth of neuroblastoma xenografts established from two different MYCN-amplified cell lines. Combination therapy more effectively inhibited the growth of small neuroblastoma xenografts than single-agent treatment, and in animals with large xenografts, total cessation of tumor growth was achieved with this treatment approach. The microvascular density was significantly reduced in the xenografts treated with combination therapy compared with controls or tumors treated with single agents. In addition, the number of structurally abnormal vessels was reduced, suggesting that these agents may "normalize" the tumor vasculature. Our results indicate that ABT-510 combined with VPA may be an effective antiangiogenic treatment strategy for children with high-risk neuroblastoma.
Assuntos
Inibidores da Angiogênese/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neuroblastoma/irrigação sanguínea , Neuroblastoma/tratamento farmacológico , Oligopeptídeos/farmacologia , Ácido Valproico/farmacologia , Animais , Apoptose/efeitos dos fármacos , Permeabilidade Capilar/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Feminino , Fator 2 de Crescimento de Fibroblastos/antagonistas & inibidores , Humanos , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Neuroblastoma/patologia , Oligopeptídeos/administração & dosagem , Ácido Valproico/administração & dosagem , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Expression of 14q32-encoded miRNAs is a favorable prognostic factor in patients with metastatic cancer. In this study, we used genomic inhibition of DNA methylation through disruption of DNA methyltransferases DNMT1 and DNMT3B and pharmacologic inhibition with 5-Aza-2'-deoxycytidine (5-Aza-dC, decitabine) to demonstrate that DNA methylation predominantly regulates expression of metastasis-suppressive miRNAs in the 14q32 cluster. DNA demethylation facilitated CCCTC-binding factor (CTCF) recruitment to the maternally expressed gene 3 differentially methylated region (MEG3-DMR), which acts as a cis-regulatory element for 14q32 miRNA expression. 5-Aza-dC activated demethylation of the MEG3-DMR and expression of 14q32 miRNAs, which suppressed adhesion, invasion, and migration (AIM) properties of metastatic tumor cells. Cancer cells with MEG3-DMR hypomethylation exhibited constitutive expression of 14q32 miRNAs and resistance to 5-Aza-dC-induced suppression of AIM. Expression of methylation-dependent 14q32 miRNAs suppressed metastatic colonization in preclinical models of lung and liver metastasis and correlated with improved clinical outcomes in patients with metastatic cancer. These findings implicate epigenetic modification via DNA methylation in the regulation of metastatic propensity through miRNA networks and identify a previously unrecognized action of decitabine on the activation of metastasis-suppressive miRNAs. SIGNIFICANCE: This study investigates epigenetic regulation of metastasis-suppressive miRNAs and the effect on metastasis.