| 1. |
- Schulte, Johannes H, et al.
(författare)
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Lysine-Specific Demethylase 1 Is Strongly Expressed in Poorly Differentiated Neuroblastoma: Implications for Therapy.
- 2009
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Ingår i: Cancer Research. - 1538-7445. ; 69, s. 2065-2071
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Tidskriftsartikel (refereegranskat)abstract
- Aberrant epigenetic changes in DNA methylation and histone acetylation are hallmarks of most cancers, whereas histone methylation was previously considered to be irreversible and less versatile. Recently, several histone demethylases were identified catalyzing the removal of methyl groups from histone H3 lysine residues and thereby influencing gene expression. Neuroblastomas continue to remain a clinical challenge despite advances in multimodal therapy. Here, we address the functional significance of the chromatin-modifying enzyme lysine-specific demethylase 1 (LSD1) in neuroblastoma. LSD1 expression correlated with adverse outcome and was inversely correlated with differentiation in neuroblastic tumors. Differentiation of neuroblastoma cells resulted in down-regulation of LSD1. Small interfering RNA-mediated knockdown of LSD1 decreased cellular growth, induced expression of differentiation-associated genes, and increased target gene-specific H3K4 methylation. Moreover, LSD1 inhibition using monoamine oxidase inhibitors resulted in an increase of global H3K4 methylation and growth inhibition of neuroblastoma cells in vitro. Finally, targeting LSD1 reduced neuroblastoma xenograft growth in vivo. Here, we provide the first evidence that a histone demethylase, LSD1, is involved in maintaining the undifferentiated, malignant phenotype of neuroblastoma cells. We show that inhibition of LSD1 reprograms the transcriptome of neuroblastoma cells and inhibits neuroblastoma xenograft growth. Our results suggest that targeting histone demethylases may provide a novel option for cancer therapy. [Cancer Res 2009;69(5):2065-71].
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| 2. |
- Schulte, Johannes H., et al.
(författare)
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The low-affinity neurotrophin receptor, p75, is upregulated in ganglioneuroblastoma/ganglioneuroma and reduces tumorigenicity of neuroblastoma cells in vivo
- 2009
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 124:10, s. 2488-2494
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Tidskriftsartikel (refereegranskat)abstract
- Neuroblastoma, the most common extracranial tumor of childhood, is derived from neural crest progenitor cells that fail to differentiate along their predefined route to sympathetic neurons or sympatho-adrenergic adrenal cells. Although expression of the high-affinity neurotrophin receptors, TrkA and TrkB, is of major importance in neuroblastoma, the significance of the expression of the low-affinity neurotrophin receptor, p75, is unclear. Here, we analyzed immunohistochemically expression of p75 on a tissue microarray of 93 primary neuroblastic tumors and assessed the functional consequences of p75 expression in neuroblastoma cell lines. We found the p75 receptor protein to be expressed in neuroblastic cells of ganglioneuromas/ganglioneuroblastomas as well as differentiating neuroblastomas, but not in poorly differentiated neuroblastomas. In an unrelated cohort of 110 neuroblastic tumors, p75 mRNA expression levels correlated with differentiation, and patients with tumors that expressed p75 at high levels had an increased event-free and overall survival. In addition, we did not detect p75 expression in 8 established neuroblastoma cell lines examined with FACS analysis. These cell lines exhibited an undifferentiated morphology, and were all derived from aggressive, high-stage neuroblastomas. Ectopic p75 expression in the SH-SY5Y neuroblastoma cell line significantly reduced proliferation, increased the fraction of apoptotic cells in vitro and resulted in a loss of tumorigenicity in nude mice. Taken together, our data suggest that expression of the p75 low-affinity neurotrophin receptor is correlated with a reduced level of tumorigenicity, and that induction of p75 expression may be an option to revert features of an aggressive tumor phenotype. (C) 2008 Wiley-Liss, Inc.
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| 3. |
- Thunnissen, Erik, et al.
(författare)
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The Use of Immunohistochemistry Improves the Diagnosis of Small Cell Lung Cancer and Its Differential Diagnosis. An International Reproducibility Study in a Demanding Set of Cases
- 2017
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Ingår i: Journal of Thoracic Oncology. - : Elsevier BV. - 1556-0864 .- 1556-1380. ; 12:2, s. 334-346
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: The current WHO classification of lung cancer states that a diagnosis of SCLC can be reliably made on routine histological and cytological grounds but immunohistochemistry (IHC) may be required, particularly (1) in cases in which histologic features are equivocal and (2) in cases in which the pathologist wants to increase confidence in diagnosis. However, reproducibility studies based on hematoxylin and eosin-stained slides alone for SCLC versus large cell neuroendocrine carcinoma (LCNEC) have shown pairwise K scores ranging from 0.35 to 0.81. This study examines whether judicious use of IHC improves diagnostic reproducibility for SCLC.Methods: Nineteen lung pathologists studied interactive digital images of 79 tumors, predominantly neuroendocrine lung tumors. Images of resection and biopsy specimens were used to make diagnoses solely on the basis of morphologic features (level 1), morphologic features along with requested IHC staining results (level 2), and all available IHC staining results (level 3).Results: For the 19 pathologists reading all 79 cases, the rate of agreement for level 1 was 64.7%, and it increased to 73.2% and 77.5% in levels 2 and 3, respectively. With IHC, K scores for four tumor categories (SCLC, LCNEC, carcinoid tumors, and other) increased in resection samples from 0.43 to 0.60 and in biopsy specimens from 0.43 to 0.64.Conclusions: Diagnosis using hematoxylin and eosin staining alone showeds moderate agreement among pathologists in tumors with neuroendocrine morphology, but agreement improved to good in most cases with the judicious use of IHC, especially in the diagnosis of SCLC. An approach for IHC in the differential diagnosis of SCLC is provided. (C) 2017 International Association for the Study of Lung Cancer.
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| 4. |
- Yang, Rongxi, et al.
(författare)
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Genome-wide analysis associates familial colorectal cancer with increases in copy number variations and a rare structural variation at 12p12.3
- 2014
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Ingår i: Carcinogenesis. - : Oxford University Press (OUP). - 0143-3334 .- 1460-2180. ; 35:2, s. 315-323
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Tidskriftsartikel (refereegranskat)abstract
- Colorectal cancer (CRC) is one of the most common cancer worldwide. However, a large number of genetic risk factors involved in CRC have not been understood. Copy number variations (CNVs) might partly contribute to the missing heritability of CRC. An increased overall burden of CNV has been identified in several complex diseases, whereas the association between the overall CNV burden and CRC risk is largely unknown. We performed a genome-wide investigation of CNVs on genomic DNA from 384 familial CRC cases and 1285 healthy controls by the Affymetrix 6.0 array. An increase of overall CNV burden was observed in familial CRC patients compared with healthy controls, especially for CNVs larger than 50kb (case/control ratio 1.66, P 0.025). In addition, we discovered for the first time a novel structural variation at 12p12.3 and determined the breakpoints by strategic PCR and sequencing. This 12p12.3 structural variation was found in four of 2862 CRC cases but not in 6243 healthy controls (P 0.0098). RERGL gene (RERG/RAS-like), the only gene influenced by the 12p12.3 structural variation, sharing most of the conserved regions with its close family member RERG tumor suppressor gene (RAS-like, estrogen-regulated, growth inhibitor), might be a novel CRC-related gene. In conclusion, this is the first study to reveal the contribution of the overall burden of CNVs to familial CRC risk and identify a novel rare structural variation at 12p12.3 containing RERGL gene to be associated with CRC.
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