Publications by authors named "Karoly Szuhai"

162 Publications

FOS Rearrangement and Expression in Cementoblastoma.

Am J Surg Pathol 2021 Mar 1. Epub 2021 Mar 1.

Departments of Pathology Radiology Cell and Chemical Biology, Leiden University Medical Center, Leiden Department of Oral and Maxillofacial Surgery/Head and Neck Surgery, Amsterdam University Medical Center/Antoni van Leeuwenhoek Hospital Department of Pathology, Academic Medical Center, Amsterdam Department of Pathology and Medical Biology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands Bone Tumour Reference Centre, Institute of Pathology, University Hospital Basel, University of Basel, Basel, Switzerland.

Cementoblastomas are rare odontogenic tumors developing in close proximity to the roots of teeth. Due to their striking morphologic resemblance to osteoblastomas of the peripheral skeleton, we set out to determine whether cementoblastomas harbor the same FOS rearrangements with overexpression of c-FOS as has recently been described for osteoblastomas. In total, 16 cementoblastomas were analyzed for FOS expression by immunohistochemistry and for FOS rearrangements by fluorescence in situ hybridization (FISH). We observed strong and diffuse staining of c-FOS in 71% of cementoblastomas and identified a FOS rearrangement in all cases (n=3) applicable for FISH. In the remaining cases, FISH failed due to decalcification. Cementoblastomas harbor similar FOS rearrangements and show overexpression of c-FOS like osteoblastomas, suggesting that both entities might represent parts of the spectrum of the same disease.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/PAS.0000000000001695DOI Listing
March 2021

Vascular Tumor Recapitulated in Endothelial Cells from hiPSCs Engineered to Express the Translocation.

Cell Rep Med 2020 Dec 22;1(9):100153. Epub 2020 Dec 22.

Department of Anatomy and Embryology, Leiden University Medical Center, 2333 ZA Leiden, the Netherlands.

Chromosomal translocations are prevalent among soft tissue tumors, including those of the vasculature such as pseudomyogenic hemangioendothelioma (PHE). PHE shows endothelial cell (EC) features and has a tumor-specific t(7;19)(q22;q13) SERPINE1-FOSB translocation, but is difficult to study as no primary tumor cell lines have yet been derived. Here, we engineer the PHE chromosomal translocation into human induced pluripotent stem cells (hiPSCs) using CRISPR/Cas9 and differentiate these into ECs (hiPSC-ECs) to address this. Comparison of parental with PHE hiPSC-ECs shows (1) elevated expression of FOSB, (2) higher proliferation and more tube formation but lower endothelial barrier function, (3) invasive growth and abnormal vessel formation in mice after transplantation, and (4) specific transcriptome alterations reflecting PHE and indicating PI3K-Akt and MAPK signaling pathways as possible therapeutic targets. The modified hiPSC-ECs thus recapitulate functional features of PHE and demonstrate how these translocation models can be used to understand tumorigenic mechanisms and identify therapeutic targets.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.xcrm.2020.100153DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7762773PMC
December 2020

Unraveling the Resistance of IGF-Pathway Inhibition in Ewing Sarcoma.

Cancers (Basel) 2020 Nov 29;12(12). Epub 2020 Nov 29.

Department of Medical Oncology, Leiden University Medical Center, P.O. Box 9600, 2300 RC Leiden, The Netherlands.

Insulin-like growth factor-1 receptor (IGF1R) inhibitors are effective in preclinical studies, but so far, no convincing benefit in clinical studies has been observed, except in some rare cases of sustained response in Ewing sarcoma patients. The mechanism of resistance is unknown, but several hypotheses are proposed. In this review, multiple possible mechanisms of resistance to IGF-targeted therapies are discussed, including activated insulin signaling, pituitary-driven feedback loops through growth hormone (GH) secretion and autocrine loops. Additionally, the outcomes of clinical trials of IGF1-targeted therapies are discussed, as well as strategies to overcome the possible resistance mechanisms. In conclusion, lowering the plasma insulin levels or blocking its activity could provide an additional target in cancer therapy in combination with IGF1 inhibition. Furthermore, because Ewing sarcoma cells predominantly express the insulin receptor A (IRA) and healthy tissue insulin receptor B (IRB), it may be possible to synthesize a specific IRA inhibitor.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3390/cancers12123568DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7759976PMC
November 2020

Translocase of the outer mitochondrial membrane complex subunit 20 (TOMM20) facilitates cancer aggressiveness and therapeutic resistance in chondrosarcoma.

Biochim Biophys Acta Mol Basis Dis 2020 12 10;1866(12):165962. Epub 2020 Sep 10.

Department of Medical Oncology, Sidney Kimmel Cancer Center, Thomas Jefferson University, Philadelphia, USA. Electronic address:

Chondrosarcoma is the second most common primary bone malignancy, representing one fourth of all primary bone sarcomas. It is typically resistant to radiation and chemotherapy treatments. However, the molecular mechanisms that contribute to cancer aggressiveness in chondrosarcomas remain poorly characterized. Here, we studied the role of mitochondrial transporters in chondrosarcoma aggressiveness including chemotherapy resistance. Histological grade along with stage are the most important prognostic biomarkers in chondrosarcoma. We found that high-grade human chondrosarcoma tumors have higher expression of the mitochondrial protein, translocase of the outer mitochondrial membrane complex subunit 20 (TOMM20), compared to low-grade tumors. TOMM20 overexpression in human chondrosarcoma cells induces chondrosarcoma tumor growth in vivo. TOMM20 drives proliferation, resistance to apoptosis and chemotherapy resistance. Also, TOMM20 induces markers of epithelial to mesenchymal transition (EMT) and metabolic reprogramming in these mesenchymal tumors. In conclusion, TOMM20 drives chondrosarcoma aggressiveness and resistance to chemotherapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.bbadis.2020.165962DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7680391PMC
December 2020

Loss of NF2 defines a genetic subgroup of non-FOS-rearranged osteoblastoma.

J Pathol Clin Res 2020 10 16;6(4):231-237. Epub 2020 Jun 16.

Department of Laboratory Medicine, Division of Clinical Genetics, Lund University, Lund, Sweden.

Osteoblastoma is a locally aggressive tumour of bone. Until recently, its underlying genetic features were largely unknown. During the past two years, reports have demonstrated that acquired structural variations affect the transcription factor FOS in a high proportion of cases. These rearrangements modify the terminal exon of the gene and are believed to stabilise both the FOS transcript and the encoded protein, resulting in high expression levels. Here, we applied in-depth genetic analyses to a series of 29 osteoblastomas, including five classified as epithelioid osteoblastoma. We found recurrent homozygous deletions of the NF2 gene in three of the five epithelioid cases and in one conventional osteoblastoma. These events were mutually exclusive from FOS mutations. Structural variations were determined by deep whole genome sequencing and the number of FOS-rearranged cases was less than previously reported (10/23, 43%). One conventional osteoblastoma displayed a novel mechanism of FOS upregulation; bringing the entire FOS gene under the control of the WNT5A enhancer that is itself activated by FOS. Taken together, we show that NF2 loss characterises a subgroup of osteoblastomas, distinct from FOS-rearranged cases. Both NF2 and FOS are involved in regulating bone homeostasis, thereby providing a mechanistic link to the excessive bone growth of osteoblastoma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cjp2.172DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7578308PMC
October 2020

Attenuated isolated 3' signal: A highly challenging therapy relevant ALK FISH pattern in NSCLC.

Lung Cancer 2020 05 10;143:80-85. Epub 2020 Mar 10.

Department of Pathology, Medical School and Clinical Center, University of Pécs, Hungary. Electronic address:

Objectives: Targeted therapies in the management of patients with lung cancer provide significantly better outcome compared to chemotherapy. Detection of the anaplastic lymphoma kinase (ALK) gene rearrangement has great predictive value for treatment with small molecule tyrosine kinase inhibitor (crizotinib and alectinib commonly). Fluorescent in situ hybridisation (FISH) assay is a basic diagnostic test designed for detecting ALK gene rearrangements. Although being considered as gold standard method by IASLC's guideline, it is often regarded as difficult and error prone. Our aim was to examine a unique atypical ALK FISH pattern, revealed during a systematic large-scale monitoring, which carries the great risk of misinterpretation, hence may result in loss of patients eligible for targeted therapy.

Materials And Methods: Tissue and cytology samples from nearly one thousand patients with advanced stage non-small cell lung cancer (NSCLC, n = 996) were routinely examined by ALK FISH and immunohistochemistry (Ventana ALK-D5F3-CDx assay). Anchored Multiplex PCR based Next Generation Sequencing (AMP-NGS) was used to detect fusion gene transcripts in ambiguous cases.

Results: Fifty-nine (5,9%) of the cases were positive with ALK FISH test. Three cases showed atypical pattern with a significantly reduced sized red (3') signal and complete loss of green signals. Digital signal measurement confirmed this finding, showing consistent attenuation of 3' signals throughout the tumours. In all three cases AMP-NGS and ALK IHC verified the presence of a fusion gene and expressed oncoprotein, respectively.

Conclusion: Approximately 5% of the 59 ALK positive cases exhibited atypical attenuated isolated 3' signal pattern. The immunohistochemistry and AMP-NGS examinations helped to clarify the presence of oncoprotein and the fusion gene, respectively. Our results emphasize the importance of extensive exploration of the genetic background of any unexpected FISH finding to avoid false diagnosis. This enables clinicians to indicate the adequate therapy with higher efficiency for patients suffering from NSCLC.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.lungcan.2020.03.007DOI Listing
May 2020

Comprehensive profiling of disease-relevant copy number aberrations for advanced clinical diagnostics of pediatric acute lymphoblastic leukemia.

Mod Pathol 2020 05 19;33(5):812-824. Epub 2019 Dec 19.

MTA-SE Momentum Molecular Oncohematology Research Group, 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary.

Acute lymphoblastic leukemia is the most common pediatric cancer characterized by a heterogeneous genomic landscape with copy number aberrations occurring at various stages of pathogenesis, disease progression, and treatment resistance. In this study, disease-relevant copy number aberrations were profiled in bone marrow samples of 91 children with B- or T-cell precursor acute lymphoblastic leukemia using digital multiplex ligation-dependent probe amplification (digitalMLPA). Whole chromosome gains and losses, subchromosomal copy number aberrations, as well as unbalanced alterations conferring intrachromosomal gene fusions were simultaneously identified with results available within 36 hours. Aberrations were observed in 96% of diagnostic patient samples, and increased numbers of copy number aberrations were detected at the time of relapse as compared with diagnosis. Comparative scrutiny of 24 matching diagnostic and relapse samples from 11 patients revealed three different patterns of clonal relationships with (i) one patient displaying identical copy number aberration profiles at diagnosis and relapse, (ii) six patients showing clonal evolution with all lesions detected at diagnosis being present at relapse, and (iii) four patients displaying conserved as well as lost or gained copy number aberrations at the time of relapse, suggestive of the presence of a common ancestral cell compartment giving rise to clinically manifest leukemia at different time points during the disease course. A newly introduced risk classifier combining cytogenetic data with digitalMLPA-based copy number aberration profiles allowed for the determination of four genetic subgroups of B-cell precursor acute lymphoblastic leukemia with distinct event-free survival rates. DigitalMLPA provides fast, robust, and highly optimized copy number aberration profiling for the genomic characterization of acute lymphoblastic leukemia samples, facilitates the decipherment of the clonal origin of relapse and provides highly relevant information for clinical prognosis assessment.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41379-019-0423-5DOI Listing
May 2020

Expanding the editable genome and CRISPR-Cas9 versatility using DNA cutting-free gene targeting based on in trans paired nicking.

Nucleic Acids Res 2020 01;48(2):974-995

Leiden University Medical Center, Department of Cell and Chemical Biology, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands.

Genome editing typically involves recombination between donor nucleic acids and acceptor genomic sequences subjected to double-stranded DNA breaks (DSBs) made by programmable nucleases (e.g. CRISPR-Cas9). Yet, nucleases yield off-target mutations and, most pervasively, unpredictable target allele disruptions. Remarkably, to date, the untoward phenotypic consequences of disrupting allelic and non-allelic (e.g. pseudogene) sequences have received scant scrutiny and, crucially, remain to be addressed. Here, we demonstrate that gene-edited cells can lose fitness as a result of DSBs at allelic and non-allelic target sites and report that simultaneous single-stranded DNA break formation at donor and acceptor DNA by CRISPR-Cas9 nickases (in trans paired nicking) mostly overcomes such disruptive genotype-phenotype associations. Moreover, in trans paired nicking gene editing can efficiently and precisely add large DNA segments into essential and multiple-copy genomic sites. As shown herein by genotyping assays and high-throughput genome-wide sequencing of DNA translocations, this is achieved while circumventing most allelic and non-allelic mutations and chromosomal rearrangements characteristic of nuclease-dependent procedures. Our work demonstrates that in trans paired nicking retains target protein dosages in gene-edited cell populations and expands gene editing to chromosomal tracts previously not possible to modify seamlessly due to their recurrence in the genome or essentiality for cell function.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1093/nar/gkz1121DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6954423PMC
January 2020

Utility of FOS as diagnostic marker for osteoid osteoma and osteoblastoma.

Virchows Arch 2020 Mar 25;476(3):455-463. Epub 2019 Nov 25.

Department of Pathology, Leiden University Medical Center, Albinusdreef 2, 2333, ZA, Leiden, The Netherlands.

Osteoid osteoma and osteoblastoma are bone-forming tumors shown to harbor FOS (87%) and FOSB (3%) rearrangements. The aim was to evaluate the immunohistochemical expression of FOS and FOSB in these tumors in comparison to other bone tumors, to evaluate the influence of decalcification, and to correlate immunohistochemical findings with the underlying genetic alteration using fluorescence in situ hybridization (FISH). Immunohistochemistry using whole sections was performed on osteoid osteoma (n=23), osteoblastoma (n=22), osteoblastoma-like osteosarcoma (n=3), reactive (n=3), and proliferative (n=11) bone lesions. Immunoreactivity in giant cell tumor of bone (n=74), aneurysmal bone cyst (n=6), chondromyxoid fibroma (n=20), osteosarcoma (n=85), chondroblastoma (n=17), and clear cell chondrosarcoma (n=20) was assessed using tissue micro arrays. Strong nuclear expression of FOS in > 50% of the tumor cells was observed in all osteoid osteomas (22/22), in 57% of osteoblastomas (12/21) and in 3/197 control cases. FOS immunoreactivity disappeared after > 3 days decalcification. FOS rearrangements were present in 94% of osteoid osteomas and osteoblastomas, with a concordance of 86% between FISH and immunohistochemistry. Two osteoblastomas (5%) were positive for FOSB, as opposed to 8/177 control cases. Additional FISH revealed no FOSB rearrangements in these cases. To conclude, in short decalcified biopsies, FOS immunohistochemistry can be used to diagnose osteoid osteoma and osteoblastoma, as overexpression is seen in the majority, being rare in their mimics. FOS immunohistochemistry should not be used after long decalcification. Moreover, low level of focal expression found in other lesions and tissues might cause diagnostic problems, in which case FISH could be employed.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00428-019-02684-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7085481PMC
March 2020

Mutation-driven epigenetic alterations as a defining hallmark of central cartilaginous tumours, giant cell tumour of bone and chondroblastoma.

Virchows Arch 2020 Jan 14;476(1):135-146. Epub 2019 Nov 14.

Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands.

Recently, specific driver mutations were identified in chondroblastoma, giant cell tumour of bone and central cartilaginous tumours (specifically enchondroma and central chondrosarcoma), sharing the ability to induce genome-wide epigenetic alterations. In chondroblastoma and giant cell tumour of bone, the neoplastic mononuclear stromal-like cells frequently harbour specific point mutations in the genes encoding for histone H3.3 (H3F3A and H3F3B). The identification of these driver mutations has led to development of novel diagnostic tools to distinguish between chondroblastoma, giant cell tumour of bone and other giant cell containing tumours. From a biological perspective, these mutations induce several global and local alterations of the histone modification marks. Similar observations are made for central cartilaginous tumours, which frequently harbour specific point mutations in the metabolic enzymes IDH1 or IDH2. Besides an altered methylation pattern on histones, IDH mutations also induce a global DNA hypermethylation phenotype. In all of these tumour types, the mutation-driven epigenetic alterations lead to a highly altered transcriptome, resulting for instance in alterations in differentiation. These genomic alterations have diagnostic impact. Further research is needed to identify the genes and signalling pathways that are affected by the epigenetic alterations, which will hopefully lead to a better understanding of the biological mechanism underlying tumourigenesis.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00428-019-02699-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6968983PMC
January 2020

[Molecular cytogenetic analyses of patients with plasma cell myeloma in Tolna and Baranya counties in Hungary].

Orv Hetil 2019 Jun;160(24):944-951

Pathologiai Intézet, Pécsi Tudományegyetem, Általános Orvostudományi Kar, Klinikai Központ Pécs, Szigeti út 12., 7624.

Plasma cell myeloma is a hematological malignancy with heterogeneous genomic landscape and diverse clinical course. Recurrent chromosomal and subchromosomal aberrations commonly occur in this entity and are associated with the pathogenesis and progression of the disease. The identification of these alterations aids genetic characterization, classification and prognostication of patients. Molecular cytogenetic investigations of plasma cell myeloma patients treated at the University of Pécs Clinical Center and János Balassa County Hospital of Tolna County, Szekszárd, between 2005 and 2018 were evaluated in our study. 231 patients were screened for genetic aberrations using fluorescence hybridization. Translocations involving the immunoglobulin heavy chain gene, losses of 1p and 17p chromosome arms, gains of 1q chromosome arm and unbalanced aberrations of chromosome 13 were investigated. Losses and gains of 1p, 1q, 5q, 12p, 13q, 16q and 17p chromosome arms were analyzed using multiplex ligation-dependent probe amplification in 42 patients. During the investigated period, 116 bone marrow karyotyping was also performed. In total, 233 genetic aberrations were identified using our targeted approaches; the frequency of specific aberrations correlated with data of the recent literature. Concordance of results gained by fluorescence hybridization and multiplex ligation-dependent probe amplification was 96.2% by analyzing the same chromosome arms. The latter technique revealed 21 additional genetic aberrations in 16/42 patient samples (38%) as compared to fluorescence hybridization. Our results suggest that the combined application of the two molecular cytogenetic methods may facilitate a more detailed characterization of genetic aberrations of plasma cell myeloma patients in Hungary. Orv Hetil. 2019; 160(24): 944-951.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1556/650.2019.31357DOI Listing
June 2019

DNA methylation profiling distinguishes Ewing-like sarcoma with EWSR1-NFATc2 fusion from Ewing sarcoma.

J Cancer Res Clin Oncol 2019 May 20;145(5):1273-1281. Epub 2019 Mar 20.

Department of Neuropathology, Institute of Pathology, University Hospital Heidelberg, Im Neuenheimer Feld 224, 69120, Heidelberg, Germany.

Purpose: Recent studies revealed divergent gene expression patterns in Ewing sarcoma (EwS) with canonical EWSR1-ETS gene fusions and undifferentiated round cell sarcomas (URCS) with EWSR1 rearrangements fused to the non-ETS gene NFATc2. Thus, the question arises whether the latter tumors really belong to EwS.

Methods: We collected five cases matching the group of URCS with EWSR1-NFATc2 fusion and performed DNA methylation and copy number profiling. Results were compared to methylation data of 30 EwS with various EWSR1-ETS fusions and one EwS with FUS-ERG fusion, 16 URCS with CIC rearrangement and 10 URCS with BCOR alteration and a total of 81 EWSR1-associated soft tissue sarcomas including 7 angiomatoid fibrous histiocytomas, 7 clear cell sarcomas of the soft tissue, 28 desmoplastic small round cell tumors, 10 extraskeletal myxoid chondrosarcomas and 29 myxoid liposarcomas.

Results: Unsupervised hierarchical clustering and t-distributed stochastic neighbor embedding analysis of DNA methylation data revealed a homogeneous methylation cluster for URCS with EWSR1-NFATc2 fusion, which clearly segregated from EwS and the other subtypes. Copy number profiles of EWSR1-NFATc2 cases showed recurrent losses on chromosome 9q and segmental gains on 20q13 and 22q12 involving the EWSR1 and NFATc2 loci, respectively.

Conclusion: In summary, URCS with EWSR1-NFATc2 fusion share a distinct DNA methylation signature and carry characteristic copy number alterations, which emphasizes that these sarcomas should be considered separately from EwS.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00432-019-02895-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7607515PMC
May 2019

Human melanoma brain metastases cell line MUG-Mel1, isolated clones and their detailed characterization.

Sci Rep 2019 03 11;9(1):4096. Epub 2019 Mar 11.

Department for Biomedical Research, Medical University of Graz, Graz, Austria.

Melanoma is a leading cause of high mortality that frequently spreads to the brain and is associated with deterioration in quality and quantity of life. Treatment opportunities have been restricted until now and new therapy options are urgently required. Our focus was to reveal the potential heterogeneity of melanoma brain metastasis. We succeeded to establish a brain melanoma metastasis cell line, namely MUG-Mel1 and two resulting clones D5 and C8 by morphological variety, differences in lipidome, growth behavior, surface, and stem cell markers. Mutation analysis by next-generation sequencing, copy number profiling, and cytogenetics demonstrated the different genetic profile of MUG-Mel1 and clones. Tumorigenicity was unsuccessfully tested in various mouse systems and finally established in a zebra fish model. As innovative treatment option, with high potential to pass the blood-brain barrier a peptide isolated from lactoferricin was studied in potential toxicity. Brain metastases are a major clinical challenge, therefore the development of relevant in vitro and in vivo models derived from brain melanoma metastases provides valuable information about tumor biology and offers great potential to screen for new innovative therapies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-019-40570-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6411871PMC
March 2019

Machine learning analysis of gene expression data reveals novel diagnostic and prognostic biomarkers and identifies therapeutic targets for soft tissue sarcomas.

PLoS Comput Biol 2019 02 20;15(2):e1006826. Epub 2019 Feb 20.

Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands.

Based on morphology it is often challenging to distinguish between the many different soft tissue sarcoma subtypes. Moreover, outcome of disease is highly variable even between patients with the same disease. Machine learning on transcriptome sequencing data could be a valuable new tool to understand differences between and within entities. Here we used machine learning analysis to identify novel diagnostic and prognostic markers and therapeutic targets for soft tissue sarcomas. Gene expression data was used from the Cancer Genome Atlas, the Genotype-Tissue Expression project and the French Sarcoma Group. We identified three groups of tumors that overlap in their molecular profiles as seen with unsupervised t-Distributed Stochastic Neighbor Embedding clustering and a deep neural network. The three groups corresponded to subtypes that are morphologically overlapping. Using a random forest algorithm, we identified novel diagnostic markers for soft tissue sarcoma that distinguished between synovial sarcoma and MPNST, and that we validated using qRT-PCR in an independent series. Next, we identified prognostic genes that are strong predictors of disease outcome when used in a k-nearest neighbor algorithm. The prognostic genes were further validated in expression data from the French Sarcoma Group. One of these, HMMR, was validated in an independent series of leiomyosarcomas using immunohistochemistry on tissue micro array as a prognostic gene for disease-free interval. Furthermore, reconstruction of regulatory networks combined with data from the Connectivity Map showed, amongst others, that HDAC inhibitors could be a potential effective therapy for multiple soft tissue sarcoma subtypes. A viability assay with two HDAC inhibitors confirmed that both leiomyosarcoma and synovial sarcoma are sensitive to HDAC inhibition. In this study we identified novel diagnostic markers, prognostic markers and therapeutic leads from multiple soft tissue sarcoma gene expression datasets. Thus, machine learning algorithms are powerful new tools to improve our understanding of rare tumor entities.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.pcbi.1006826DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6398862PMC
February 2019

Molecular Pathology of Bone Tumors.

J Mol Diagn 2019 03 18;21(2):171-182. Epub 2018 Dec 18.

Department of Pathology, Leiden University Medical Center, Leiden, the Netherlands. Electronic address:

Although classic histomorphology is the cornerstone of bone tumor diagnostics, this field has rapidly evolved since the advancement of new molecular techniques. The identification of novel genetic alterations in bone tumors has led to more insight into the genetic background of these tumors, which has resulted in a more prominent role of molecular pathology in daily practice. Numerous studies have been conducted in the past few decades and illustrated that based on molecular alterations, bone tumors can be roughly classified as tumors with simple karyotypes and those with complex karyotypes. The first group can be subclassified as tumors that carry specific translocations, somatic gene mutations, or more or less specific amplifications. On the other hand, sarcomas with complex karyotypes usually lack specific alterations. Many techniques are available for the detection of recurrent genetic alterations, now also including IHC analysis, and this review focuses on assays routinely performed in molecular diagnostics. Subsequently, tumor classes with distinct genetic abnormalities are discussed and illustrated by more specific examples, and the usefulness of molecular pathology in routine diagnostics is highlighted.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmoldx.2018.11.002DOI Listing
March 2019

PRAME and HLA Class I expression patterns make synovial sarcoma a suitable target for PRAME specific T-cell receptor gene therapy.

Oncoimmunology 2018;7(12):e1507600. Epub 2018 Sep 11.

Department of Hematology, Leiden University Medical Center, Leiden, The Netherlands.

Synovial sarcoma expresses multiple cancer testis antigens that could potentially be targeted by T-cell receptor (TCR) gene therapy. In this study we investigated whether PRAME-TCR-gene therapy could be an effective treatment for synovial sarcoma by investigating the potential of PRAME-specific T-cells to recognize sarcoma cells and by evaluating the expression patterns of and HLA class I (HLA-I) in synovial sarcoma tumor samples. All expressing sarcoma cell lines, including 2 primary synovial sarcoma cell cultures (passage < 3), were efficiently recognized by PRAME-specific T-cells. mRNA FISH demonstrated that was expressed in all synovial sarcoma samples, mostly in an homogeneous pattern. Immunohistochemistry demonstrated low HLA-I baseline expression in synovial sarcoma, but its expression was elevated in specific areas of the tumors, especially in biphasic components of biphasic synovial sarcoma. In 5/11 biphasic synovial sarcoma patients and in 1/17 monophasic synovial sarcoma patients, elevated HLA-I on tumor cells was correlated with infiltration of T-cells in these specific areas. In conclusion, low-baseline expression of HLA-I in synovial sarcoma is elevated in biphasic areas and in areas with densely infiltrating T-cells, which, in combination with homogeneous and high expression, makes synovial sarcoma potentially a suitable candidate for PRAME-specific TCR-gene therapy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/2162402X.2018.1507600DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6279314PMC
September 2018

Does CSF1 overexpression or rearrangement influence biological behaviour in tenosynovial giant cell tumours of the knee?

Histopathology 2019 Jan 11;74(2):332-340. Epub 2018 Nov 11.

Department of Cell and Chemical biology, Leiden University Medical Center, Leiden, the Netherlands.

Aims: Localised- and diffuse-type tenosynovial giant cell tumours (TGCT) are regarded as different clinical and radiological TGCT types. However, genetically and histopathologically they seem indistinguishable. We aimed to correlate CSF1 expression and CSF1 rearrangement with the biological behaviour of different TGCT-types with clinical outcome (recurrence).

Methods And Results: Along a continuum of extremes, therapy-naive knee TGCT patients with >3-year follow-up, mean age 43 (range = 6-71) years and 56% females were selected. Nine localised (two recurrences), 16 diffuse-type (nine recurrences) and four synovitis as control were included. Rearrangement of the CSF1 locus was evaluated with split-apart fluorescence in-situ hybridisation (FISH) probes. Regions were selected to score after identifying CSF1-expressing regions, using mRNA ISH with the help of digital correlative microscopy. CSF1 rearrangement was considered positive in samples containing >2 split signals/100 nuclei. Irrespective of TGCT-subtype, all cases showed CSF1 expression and in 76% CSF1 rearrangement was detected. Quantification of CSF1-expressing cells was not informative, due to the extensive intratumour heterogeneity. Of the four synovitis cases, two also showed CSF1 expression without CSF1 rearrangement. No correlation between CSF1 expression or rearrangement with clinical subtype and local recurrence was detected. Both localised and diffuse TGCT cases showed a scattered distribution in the tissue of CSF1-expressing cells.

Conclusion: In diagnosing TGCT, CSF1 mRNA-ISH, in combination with CSF1 split-apart FISH using digital correlative microscopy, is an auxiliary diagnostic tool to identify rarely occurring neoplastic cells. This combined approach allowed us to detect CSF1 rearrangement in 76% of the TGCT cases. Neither CSF1 expression nor presence of CSF1 rearrangement could be associated with the difference in biological behaviour of TGCT.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/his.13744DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7379608PMC
January 2019

Genomic analysis reveals recurrent deletion of JAK-STAT signaling inhibitors HNRNPK and SOCS1 in mycosis fungoides.

Genes Chromosomes Cancer 2018 12 25;57(12):653-664. Epub 2018 Oct 25.

Department of Dermatology, Leiden University Medical Center, Leiden, The Netherlands.

Mycosis fungoides (MF) is the most common cutaneous T-cell lymphoma (CTCL). Causative genetic alterations in MF are unknown. The low recurrence of pathogenic small-scale mutations (ie, nucleotide substitutions, indels) in the disease, calls for the study of additional aspects of MF genetics. Here, we investigated structural genomic alterations in tumor-stage MF by integrating whole-genome sequencing and RNA-sequencing. Multiple genes with roles in cell physiology (n = 113) and metabolism (n = 92) were found to be impacted by genomic rearrangements, including 47 genes currently implicated in cancer. Fusion transcripts involving genes of interest such as DOT1L, KDM6A, LIFR, TP53, and TP63 were also observed. Additionally, we identified recurrent deletions of genes involved in cell cycle control, chromatin regulation, the JAK-STAT pathway, and the PI-3-K pathway. Remarkably, many of these deletions result from genomic rearrangements. Deletion of tumor suppressors HNRNPK and SOCS1 were the most frequent genetic alterations in MF after deletion of CDKN2A. Notably, SOCS1 deletion could be detected in early-stage MF. In agreement with the observed genomic alterations, transcriptome analysis revealed up-regulation of the cell cycle, JAK-STAT, PI-3-K and developmental pathways. Our results position inactivation of HNRNPK and SOCS1 as potential driver events in MF development.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/gcc.22679DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6282857PMC
December 2018

Molecular Analysis of Gene Fusions in Bone and Soft Tissue Tumors by Anchored Multiplex PCR-Based Targeted Next-Generation Sequencing.

J Mol Diagn 2018 09 20;20(5):653-663. Epub 2018 Aug 20.

Department of Pathology, Leiden University Medical Center, Leiden, the Netherlands. Electronic address:

Molecular assays for translocation detection in bone and soft tissue tumors have gradually been incorporated into routine diagnostics. However, conventional methods such as fluorescence in situ hybridization (FISH) and reverse transcriptase-PCR come with several drawbacks. In this study, the applicability of a novel technique termed anchored multiplex PCR (AMP) for next-generation sequencing (NGS), using the Archer FusionPlex Sarcoma kit, aimed at 26 genes, was evaluated and compared with FISH and reverse transcriptase-PCR. In case of discrepant results, further analysis occurred with a third independent technique. Eighty-one samples were subjected to AMP-based targeted NGS, and 86% (n = 70) were successfully conducted and were either fusion positive (n = 48) or fusion negative, but met all criteria for good quality (n = 22). A concordance of 90% was found between NGS and conventional techniques. AMP-based targeted NGS showed superior results, as in four cases reverse transcriptase-PCR and FISH were false negative. Moreover, because the assay targets one partner of a gene fusion, novel or rare fusion partners can be identified. Indeed, it revealed COL1A1 and SEC31A as novel fusion partners for USP6 in nodular fasciitis. Despite the fact that fusions involving genes outside the selectively captured region cannot be detected and false-negative results due to poor quality samples can be encountered, this method has demonstrated excellent diagnostic utility for translocation detection in sarcomas.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmoldx.2018.05.007DOI Listing
September 2018

High-Throughput Copy Number Profiling by Digital Multiplex Ligation-Dependent Probe Amplification in Multiple Myeloma.

J Mol Diagn 2018 11 8;20(6):777-788. Epub 2018 Aug 8.

MTA-SE Lendület Molecular Oncohematology Research Group, 1st Department of Pathology and Experimental Cancer Research, Semmelweis University, Budapest, Hungary; Department of Pathology, University of Pecs Medical School, Pecs, Hungary. Electronic address:

Multiple myeloma (MM) is a genetically heterogeneous disease with a diverse clinical outcome. Copy number alterations (CNAs), including whole chromosome and subchromosomal gains and losses, are common contributors of the pathogenesis and have demonstrated prognostic impact in MM. We tested the performance of digital multiplex ligation-dependent probe amplification (digitalMLPA), a novel technique combining MLPA and next-generation sequencing, to detect disease-related CNAs. Copy number status at 371 genomic loci was simultaneously analyzed in 56 diagnostic bone marrow samples, which were also examined by conventional MLPA and interphase fluorescence in situ hybridization (iFISH). On average, digitalMLPA identified 4.4 subchromosomal CNAs per patient. The increased number of probes compared with conventional MLPA allowed a detailed mapping of CNAs, especially on chromosome 1, where 24 different patterns were observed in 38 patients harboring loss(1p) and/or gain(1q). iFISH, MLPA, and digitalMLPA results at loci investigated by multiple methods showed a congruency of 95%. Besides precise characterization of hyperdiploid karyotypes not efficiently achievable by iFISH or MLPA, digitalMLPA unraveled 156 CNAs not detected by the other two methods in 45 patients (80%). In addition, we provide proof of principle that digitalMLPA can detect known point mutations, in this case the BRAF. Our study demonstrates the robustness of digitalMLPA to profile CNAs and to screen point mutations in MM, which could efficiently be used in myeloma diagnostics.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmoldx.2018.06.004DOI Listing
November 2018

Bioorthogonally Applicable Fluorescence Deactivation Strategy for Receptor Kinetics Study and Theranostic Pretargeting Approaches.

Chembiochem 2018 Jun 4. Epub 2018 Jun 4.

Interventional Molecular Imaging Laboratory, Department of Radiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA, Leiden, The Netherlands.

The availability of a receptor for theranostic pretargeting approaches was assessed by use of a new click-chemistry-based deactivatable fluorescence-quenching concept. The efficacy was evaluated in a cell-based model system featuring both membranous (available) and internalized (unavailable) receptor fractions of the clinically relevant receptor chemokine receptor 4 (CXCR4). Proof of concept was achieved with a deactivatable tracer consisting of a CXCR4-specific peptide functionalized with a Cy5 dye bearing a chemoselective azide handle (N -Cy5-AcTZ14011). Treatment with a Cy7 quencher dye (Cy7-DBCO) resulted in optically silent Cy7-[click]-Cy5-AcTZ14011. In situ, a >90 % FRET-based reduction of the signal intensity of N -Cy5-AcTZ14011 [K =(222.4±25.2) nm] was seen within minutes after quencher addition. In cells, discrimination between the membranous and the internalized receptor fraction could be achieved through quantitative assessment of quenching/internalization kinetics. Similar evaluation of an activatable tracer variant based on the same targeting moiety (Cy5-S-S-Cy3-AcTZ14011) was unsuccessful in vitro. As such, using the described deactivatable approach to screen membrane receptors and their applicability in receptor-(pre-)targeted theranostics can become straightforward.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/cbic.201800229DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6120557PMC
June 2018

[Multiplex ligation-dependent probe amplification in oncohematological diagnostics and research].

Orv Hetil 2018 Apr;159(15):583-592

I. Patológiai és Kísérleti Rákkutató Intézet, MTA-SE Lendület Molekuláris Onkohematológia Kutatócsoport, Semmelweis Egyetem, Általános Orvostudományi Kar Budapest, Üllői út 26., 1085.

Genetic abnormalities associated with the development, progression and treatment resistance of hematological malignancies are extensively characterized. Rapid, reliable and cost-efficient techniques are needed to screen the clinically relevant aberrations in routine diagnostics. Multiplex ligation-dependent probe amplification is an efficient tool to analyze genomic copy number aberrations at 55-60 different genomic loci. The method allows the profiling of prognostic and predictive markers; thus, it can efficiently be combined with karyotyping and fluorescence in situ hybridization, the most commonly used diagnostic techniques to detect cytogenetic lesions. Furthermore, the method can interrogate methylation status and unravel point mutations at specific sites, providing results in 24 hours. Here, we describe the technical background of multiplex ligation-dependent probe amplification, summarize its advantages and limitations as well as discuss its role in oncohematological diagnostics and research. Finally, future outlook is provided, with emphasis on recent technological advances related to next-generation sequencing. Orv Hetil. 2018; 159(15): 583-592.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1556/650.2018.31053DOI Listing
April 2018

Tissue Damage Caused by Myeloablative, but Not Non-Myeloablative, Conditioning before Allogeneic Stem Cell Transplantation Results in Dermal Macrophage Recruitment without Active T-Cell Interaction.

Front Immunol 2018 27;9:331. Epub 2018 Feb 27.

Department of Hematology, Leiden University Medical Center, Leiden, Netherlands.

Introduction: Conditioning regimens preceding allogeneic stem cell transplantation (alloSCT) can cause tissue damage and acceleration of the development of graft-versus-host disease (GVHD). T-cell-depleted alloSCT with postponed donor lymphocyte infusion (DLI) may reduce GVHD, because tissue injury can be restored at the time of DLI. In this study, we investigated the presence of tissue injury and inflammation in skin during the period of hematologic recovery and immune reconstitution after alloSCT.

Methods: Skin biopsies were immunohistochemically stained for HLA class II, CD1a, CD11c, CD40, CD54, CD68, CD86, CD206, CD3, and CD8. HLA class II-expressing cells were characterized as activated T-cells, antigen-presenting cells (APCs), or tissue repairing macrophages. In sex-mismatched patient and donor couples, origin of cells was determined by multiplex analysis combining XY-FISH and fluorescent immunohistochemistry.

Results: No inflammatory environment due to pretransplant conditioning was detected at the time of alloSCT, irrespective of the conditioning regimen. An increase in HLA class II-positive macrophages and CD3 T-cells was observed 12-24 weeks after myeloablative alloSCT, but these macrophages did not show signs of interaction with the co-localized T-cells. In contrast, during GVHD, an increase in HLA class II-expressing cells coinciding with T-cell interaction was observed, resulting in an overt inflammatory reaction with the presence of activated APC, activated donor T-cells, and localized upregulation of HLA class II expression on epidermal cells. In the absence of GVHD, patient derived macrophages were gradually replaced by donor-derived macrophages although patient-derived macrophages were detectable even 24 weeks after alloSCT.

Conclusion: Conditioning regimens cause tissue damage in the skin, but this does not result in a local increase of activated APC. In contrast to the inflamed situation in GVHD, when interaction takes place between activated APC and donor T-cells, the tissue damage caused by myeloablative alloSCT results in dermal recruitment of HLA class II-positive tissue repairing macrophages co-existing with increased numbers of patient- and donor-derived T-cells, but without signs of specific interaction and initiation of an immune response. Thus, the local skin damage caused by the conditioning regimen appears to be insufficient as single factor to provoke GVHD induction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fimmu.2018.00331DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5835032PMC
March 2019

Telatinib Is an Effective Targeted Therapy for Pseudomyogenic Hemangioendothelioma.

Clin Cancer Res 2018 06 6;24(11):2678-2687. Epub 2018 Mar 6.

Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands.

Pseudomyogenic hemangioendothelioma (PHE) is an extremely rare locally aggressive neoplasm with endothelial differentiation, which often presents with multiple lesions. These tumors have characteristic SERPINE1-FOSB fusions. We report a 17 years old patient with advanced unresectable PHE with a durable complete remission to the multi-tyrosine kinase inhibitor telatinib. The aim of this study was to generate an model for PHE, to study the functional consequences of SERPINE1-FOSB in endothelial cells, and its interaction with telatinib, to biologically substantiate the complete response to telatinib. As the fusion results in overexpression of a truncated form of FOSB, we overexpressed truncated FOSB in normal endothelial cells. Truncated FOSB significantly affected tumor growth in three-dimensional (3D) on matrigel with increased and sustained sprouting. Moreover, truncated FOSB acted as an active transcription factor capable to regulate its own transcription, as well as to upregulate and expression (four-fold). Telatinib decreased proliferation and tumor growth in 3D and induced apoptosis. As expected, telatinib blocked VEGF signaling as phosphorylation of ERK was abolished. Interestingly, in FOSB overexpressing cells, telatinib specifically affected PDGFRA, FLT1, and FLT4 signaling and downregulated SERPINE1, thereby affecting the self-regulation of the fusion gene. We provide a biological substantiation of a complete clinical remission that was seen in a patient with PHE, showing that telatinib indirectly interferes with the self-regulated expression of the fusion product. Thus, telatinib or any other currently available VEGFR1-4/PDGFRA inhibitor could be a highly specific treatment option for patients with multifocal unresectable PHE. .
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1158/1078-0432.CCR-17-3512DOI Listing
June 2018

Coronaviruses and arteriviruses display striking differences in their cyclophilin A-dependence during replication in cell culture.

Virology 2018 04 15;517:148-156. Epub 2017 Dec 15.

Molecular Virology Laboratory, Department of Medical Microbiology, Leiden University Medical Center, Leiden, The Netherlands. Electronic address:

Cyclophilin A (CypA) is an important host factor in the replication of a variety of RNA viruses. Also the replication of several nidoviruses was reported to depend on CypA, although possibly not to the same extent. These prior studies are difficult to compare, since different nidoviruses, cell lines and experimental set-ups were used. Here, we investigated the CypA dependence of three distantly related nidoviruses that can all replicate in Huh7 cells: the arterivirus equine arteritis virus (EAV), the alphacoronavirus human coronavirus 229E (HCoV-229E), and the betacoronavirus Middle East respiratory syndrome coronavirus (MERS-CoV). The replication of these viruses was compared in the same parental Huh7 cells and in CypA-knockout Huh7 cells generated using CRISPR/Cas9-technology. CypA depletion reduced EAV yields by ~ 3-log, whereas MERS-CoV progeny titers were modestly reduced (3-fold) and HCoV-229E replication was unchanged. This study reveals that the replication of nidoviruses can differ strikingly in its dependence on cellular CypA.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.virol.2017.11.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7112125PMC
April 2018

Functional analyses of a human vascular tumor FOS variant identify a novel degradation mechanism and a link to tumorigenesis.

J Biol Chem 2017 12 17;292(52):21282-21290. Epub 2017 Nov 17.

Molecular Cell Biology, Leiden University Medical Center (LUMC), 2300 RC Leiden, The Netherlands

Epithelioid hemangioma is a locally aggressive vascular neoplasm, found in bones and soft tissue, whose cause is currently unknown, but may involve oncogene activation. FOS is one of the earliest viral oncogenes to be characterized, and normal cellular FOS forms part of the activator protein 1 (AP-1) transcription factor complex, which plays a pivotal role in cell growth, differentiation, and survival as well as the DNA damage response. Despite this, a causal link between aberrant FOS function and naturally occurring tumors has not yet been established. Here, we describe a thorough molecular and biochemical analysis of a mutant FOS protein we identified in these vascular tumors. The mutant protein lacks a highly conserved helix consisting of the C-terminal four amino acids of FOS, which we show is indispensable for fast, ubiquitin-independent FOS degradation via the 20S proteasome. Our work reveals that FOS stimulates endothelial sprouting and that perturbation of normal FOS degradation could account for the abnormal vessel growth typical of epithelioid hemangioma. To the best of our knowledge, this is the first functional characterization of mutant FOS proteins found in tumors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1074/jbc.C117.815845DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5766951PMC
December 2017

DNA methylation and transcriptional trajectories during human development and reprogramming of isogenic pluripotent stem cells.

Nat Commun 2017 10 13;8(1):908. Epub 2017 Oct 13.

Department of Anatomy and Embryology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands.

Determining cell identity and maturation status of differentiated pluripotent stem cells (PSCs) requires knowledge of the transcriptional and epigenetic trajectory of organs during development. Here, we generate a transcriptional and DNA methylation atlas covering 21 organs during human fetal development. Analysis of multiple isogenic organ sets shows that organ-specific DNA methylation patterns are highly dynamic between week 9 (W9) and W22 of gestation. We investigate the impact of reprogramming on organ-specific DNA methylation by generating human induced pluripotent stem cell (hiPSC) lines from six isogenic organs. All isogenic hiPSCs acquire DNA methylation patterns comparable to existing hPSCs. However, hiPSCs derived from fetal brain retain brain-specific DNA methylation marks that seem sufficient to confer higher propensity to differentiate to neural derivatives. This systematic analysis of human fetal organs during development and associated isogenic hiPSC lines provides insights in the role of DNA methylation in lineage commitment and epigenetic reprogramming in humans.While DNA methylation and gene expression data are widely available for animal models, comprehensive data from human development is rarer. Here, the authors generated transcriptional and DNA methylation data from 21 organs during human development and 6 isogenic induced pluripotent stem cell lines.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41467-017-01077-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5640655PMC
October 2017

Notochordal Tumors: An Update on Molecular Pathology with Therapeutic Implications.

Surg Pathol Clin 2017 Sep 29;10(3):637-656. Epub 2017 Jun 29.

Department of Molecular Cell Biology, Leiden University Medical Center, PO Box: 9600, Post Zone: R-01-P, Leiden 2300 RC, The Netherlands.

Recent molecular investigations of chordoma show common expression of various receptor tyrosine kinases and activation of downstream signaling pathways contributing to tumor growth and progression. The transcription factor brachyury (also known as T) is important in notochord differentiation, and germline duplication of the gene is often found in familial chordomas. Nuclear expression of brachyury is consistent in chordoma and in benign notochordal cell tumor. Based on the molecular evidence, targeting of several kinds of molecular agents has been attempted for the treatment of uncontrolled chordomas and achieved partial response or stable condition in many cases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.path.2017.04.008DOI Listing
September 2017

Actomyosin drives cancer cell nuclear dysmorphia and threatens genome stability.

Nat Commun 2017 07 24;8:16013. Epub 2017 Jul 24.

Cell Division and Aneuploidy Laboratory, Cancer Research UK London Research Institute, Clare Hall Laboratories, South Mimms, Hertfordshire EN6 3LD, UK.

Altered nuclear shape is a defining feature of cancer cells. The mechanisms underlying nuclear dysmorphia in cancer remain poorly understood. Here we identify PPP1R12A and PPP1CB, two subunits of the myosin phosphatase complex that antagonizes actomyosin contractility, as proteins safeguarding nuclear integrity. Loss of PPP1R12A or PPP1CB causes nuclear fragmentation, nuclear envelope rupture, nuclear compartment breakdown and genome instability. Pharmacological or genetic inhibition of actomyosin contractility restores nuclear architecture and genome integrity in cells lacking PPP1R12A or PPP1CB. We detect actin filaments at nuclear envelope rupture sites and define the Rho-ROCK pathway as the driver of nuclear damage. Lamin A protects nuclei from the impact of actomyosin activity. Blocking contractility increases nuclear circularity in cultured cancer cells and suppresses deformations of xenograft nuclei in vivo. We conclude that actomyosin contractility is a major determinant of nuclear shape and that unrestrained contractility causes nuclear dysmorphia, nuclear envelope rupture and genome instability.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/ncomms16013DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5527285PMC
July 2017