A Comprehensive High-Resolution Genomic Analysis of Primary Central Nervous System Lymphomas Shows a Highly Complex Karyotype Characterized by Abnormalities Affecting Multiple Genes Involved in Critical Pathways Associated with Lymphocyte Maturation and Survival.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 4637-4637
Author(s):  
Esteban Braggio ◽  
Mark Law ◽  
W.R Macon ◽  
Brian Patrick O'Neill ◽  
Rafael Fonseca

Abstract Abstract 4637 Primary central nervous system lymphoma (PCNSL) is an aggressive form of extra-nodal, high-grade, non-Hodgkin B-cell neoplasm. It originates in the brain, leptomeninges, spinal cord or eyes and typically remains confined to the CNS. Further immunophenotypic characterization has revealed that these tumors have overlapping features of germinal center and activated B-cell differentiation. Although the cells of origin are lymphocytes, PCNSL should be considered a brain tumor because its therapeutic challenges resemble those of other brain tumors. Regarding the molecular pathogenesis of PCNSL, there is significantly less information in comparison with systemic lymphomas. The aim of this study was to perform a comprehensive high-resolution genomic analysis in a cohort of PCNSL cases to better characterize the disease at chromosomal and gene level. Copy-number abnormalities were analyzed in seven PCNSL by array-based comparative genomic hybridization (aCGH) using SurePrint G3 (1 million probes, ∼4 Kb resolution) microarray (Agilent). Overall, PCNSL cases were characterized by highly complex genomes with a median of 23 copy-number abnormalities per patient (range 16-49). The whole genomic regions affected in abnormalities correspond to areas between 3% and 29% of the human genome. Globally, 43 chromosomal regions were affected in a recurrent fashion (24 areas involved in recurrent deletions and 19 in copy-number gains). Gain of 12q12-q24.33 and losses of 9p21.3 and 6q were the most common abnormalities found in 71% patients each (5 out of 7). There was not a unique deleted region on 6q to all patients, with 6q14.1-q14.3, 6q16.3-q22.2 and 6q25.3-q26 losses being found in 4 out of 5 cases with 6q deletions. None of these regions include PTPRK, which has been previously proposed as a potential modulator of PCNSL progression. CDKN2A was the sole gene included in all cases with 9p21.3, being biallelically deleted in two out of 5 cases. Minimal deleted genes were also delineated in 3p21.1 (minimal affected area of 0.03Mb) and 3q26.32 (0.27Mb) in 44% of cases each. Those regions included PRKCD (inhibits B-cell growth through transcriptional regulation of IL-6) and TBL1XR1 (corepressor of nuclear hormone receptor), respectively. Overall, a total of 22 genes were included in homozygous deletions in at least one case. Besides CDKN2A (cell cycle), other genes of interest associated with the development and activation of T cells (TOX, CD58) were biallelically affected. Focal monoallelic deletions affecting negative regulators of the NFkB signaling pathway (MAP4K1, TANK, TAX1BP1, TRIB3), cell cycle (RB1) and immune-cell regulation (SIRPB1, CBLB, NFATC2) were also identified. Of interest, no copy-number abnormalities were identified affecting TP53 in any patient. Several chromosomal breakpoints were identified inside genes that encodes transcription factors previously identified as being part of fusion protein in other hematological malignancies (FOXP1, ETV6 and NCOA2) thus suggesting the potential existence of fusion proteins including these genes. Cytogenetic and genetic approaches are being currently used to validate this hypothesis. This is the first study characterizing a cohort of PCNSL cases by using this comprehensive high-resolution approach. Regarding the small number of cases analyzed so far, we can confirm the existence of a highly complex genome, mainly characterized by abnormalities affecting a plethora of genes involved in lymphocyte development, activation and NF-kB signaling pathways regulation. Molecular analyses are ongoing to validate these findings in a larger cohort of PCNSL patients. Disclosures: Fonseca: Otsuka: Consultancy; BMS: Consultancy; Amgen: Consultancy; Medtronic : Consultancy; Genzyme: Consultancy.

Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 2687-2687
Author(s):  
Kenichi Yoshida ◽  
Rie Nakamoto-Matsubara ◽  
Kenichi Chiba ◽  
Yusuke Okuno ◽  
Nobuyuki Kakiuchi ◽  
...  

Abstract Introduction Primary central nervous system lymphoma (PCNSL) is a rare subtype of non-Hodgkin lymphoma, of which approximately 95% are diffuse large B-cell lymphomas (DLBCLs). Despite the substantial development of intensive chemotherapy during the past two decades, overall clinical outcome of PCNSL has been poorly improved especially in elderly and so has been our knowledge about the molecular pathogenesis of PCNSL, in terms of driver alterations that are relevant to the development of PCNSL. Method To delineate the genetic basis of PCNSL pathogenesis, we performed a comprehensive genetic study. We first analyzed paired tumor/normal DNA from 35 PCNSL cases by whole-exome sequencing (WES). Significantly mutated genes identified by WES and previously known mutational targets in PCNSL and systemic DLBCL were further screened for mutations using SureSelect-based targeted deep sequencing (Agilent) in an extended cohort of PCNSL cases (N = 90). Copy number alterations (CNAs) have been also investigated using SNP array-karyotyping (N =54). We also analyzed WES and SNP array data of systemic DLBCL cases (N = 49) generated by the Cancer Genome Atlas Network (TCGA) to unravel the genetic difference between PCNSL and systemic DLBCL. Results The mean number of nonsynonymous mutations identified by WES was 183 per sample, which was comparable to the figure in systemic DLBCL and characterized by frequent somatic hypermutations (SHMs) involving non-Ig genes. A higher representation of C>T transition involving CpG dinucleotides and hotspot mutations within the WRCY motif targeted by SHM further suggested the involvement of activation-induced cytidine deaminase (AID) in the pathogenesis of PCNSL. We found 12 genes significantly mutated in PCNSL (q < 0.1), including MYD88, PIM1, HLA-A, TMEM30A, B2M, PRDM1, UBE2A, HIST1H1C, as well as several previously unreported mutational targets in systemic DLBCL or PCNSL, such as SETD1B, GRB2, ITPKB, EIF4A2. Copy number analysis identified recurrent genomic segments affected by focal deletions (N = 27) and amplifications (N = 10), most of which included driver genes targeted by recurrent somatic mutations or known targets of focal CNAs such as CDKN2A and FHIT. Subsequent targeted sequencing finally identified a total of 107 significantly mutated genes, of which 43 were thought to be targeted by SHM according to their mutational signature and genomic distribution. Most cases with PCNSL (98%) had mutations and CNAs involving genes that are relevant to constitutive NF-KB/Toll-like receptor (TLR)/BCR activity, including those in MYD88 (80%), CD79B/A (60%), CARD11 (18%), TNFAIP3 (26%), GRB2 (24%) and ITPKB (23%). Genetic alterations implicated in escape from immunosurveillance were also frequently identified in as many as 76% of cases. Mutations of HLA-B (64%), HLA-A (36%), HLA-C (28%), B2M (14%) and CD58 (12%) were commonly detected in addition to CNAs in 6p21.32 (HLA class II), 1p13.1 (CD58) and 15q15.2 (B2M), suggesting the importance of immune escape in the pathogenesis of PCNSL. SHMs were also seen in most cases (98%), which affected not only known targets of AID including PIM1, IGLL5 and BTG2 but also previously unreported genes involved in cell proliferation, apoptosis, or B cell development. The pattern of frequently mutated genes in PNCSL was more uniform compared with that in systemic DLBCL, and similar to that found in the activated B cell subtype of DLBCL (ABC-DLBCL), which was in accordance with the previous report of immunophenotypic analysis of PCNSL. On the other hand, mutations of HLA class I genes (HLA-B, HLA-A) were more frequently mutated in PCNSL compared with ABC-type DLBCL. Conclusion WES, SNP array karyotyping and follow-up targeted sequencing of a large cohort of PCNSL cases revealed the genetic landscape of PCNSL, which were more homogeneous than that of systemic DLBCL, and thought to be involved in activation of constitutive NF-KB/TLR/BCR signaling, escape from immunosurveillance, as well as highly frequent SHMs. Disclosures No relevant conflicts of interest to declare.


Blood ◽  
2011 ◽  
Vol 117 (4) ◽  
pp. 1291-1300 ◽  
Author(s):  
Chang Ohk Sung ◽  
Sang Cheol Kim ◽  
Sivasundaram Karnan ◽  
Kennosuke Karube ◽  
Hyung Jin Shin ◽  
...  

Abstract Of the genetic changes in primary central nervous system lymphoma (PCNSL), little is known. To detect copy number alterations and differentially expressed genes in PCNSL, we analyzed a total of 12 PCNSL samples with high-resolution array-based comparative genomic hybridization and performed expression profiling in 7 of the 12 samples. The most frequent deletion found in 8 patients (66.7%) occurred in 9p21.3 containing CDKN2A. We compiled the top 96 genes (family-wise error rate, P < .05) showing the greatest differential expression between PCNSL and normal lymph node tissues. From these, we selected 8 candidate genes (NPFFR2, C4orf7, OSMR, EMCN, TPO, FNDC1, COL12A1, and MSC) in which expression changes were associated with copy number aberrations. All 8 genes showed both down-regulation in expression microarray and deletion in array-based comparative genomic hybridization analyses. These genes participate in cell signaling or cell adhesion. In addition, low mRNA expression of C4orf7 was significantly associated with poor survival (P = .0425). Using gene set enrichment analysis, we identified several signal transduction pathways, such as Janus kinase-signal transducers and activators of transcription pathway and adhesion-related pathways, which may be involved in pathogenesis of PCNSL. In conclusion, this study identified novel tumor suppressor genes that may serve as therapeutic targets of PCNSL.


2020 ◽  
Vol 19 (3) ◽  
pp. 165-173
Author(s):  
Xiaowei Zhang ◽  
Yuanbo Liu

Primary Central Nervous System Lymphoma (PCNSL) is a rare invasive extranodal non- Hodgkin lymphoma, a vast majority of which is Diffuse Large B-Cell Lymphoma (DLBCL). Although high-dose methotrexate-based immunochemotherapy achieves a high remission rate, the risk of relapse and related death remains a crucial obstruction to long-term survival. Novel agents for the treatment of lymphatic malignancies have significantly broadened the horizons of therapeutic options for PCNSL. The PI3K/AKT/mTOR signaling pathway is one of the most important pathways for Bcell malignancy growth and survival. Novel therapies that target key components of this pathway have shown antitumor effects in many B-cell malignancies, including DLBCL. This review will discuss the aberrant status of the PI3K/AKT/mTOR signaling pathways in PCNSL and the application prospects of inhibitors in hopes of providing alternative clinical therapeutic strategies and improving prognosis.


2020 ◽  
pp. 194187442096756
Author(s):  
Prashant Anegondi Natteru ◽  
Shashank Shekhar ◽  
Lakshmi Ramachandran Nair ◽  
Hartmut Uschmann

Primary central nervous system lymphoma (PCNSL) is an uncommon variant of extra-nodal non-Hodgkin’s lymphoma. Three regions can be involved in PCNSL: the brain, the spine, or the vitreus and retina. Spinal PCNSL is rare. It can mimic neoplasm, infection, and inflammation. Diagnostic confirmation is by tissue biopsy, and even then, tissue corroboration may be altered by an inflammatory overlay. We report a 59-year-old woman who we saw after she had 4 weeks of ascending tetraparesis plus bowel and bladder incontinence. Upon presentation, the patient was ventilator-dependent and locked-in. She reported normal sensation through eye-blinking. Magnetic resonance imaging (MRI) brain revealed signal intensity in the bilateral corona radiata and restricted diffusion in the right thalamus, whereas, MRI cervical, and thoracic spine showed T2 prolongation in the anterior medulla and upper cervical cord, with enhancement to C2-C3, and long segment hyperintensity from T1-T9 levels, respectively, suggestive of neuromyelitis optica spectrum disorder. Cerebrospinal fluid cytomorphology and flow cytometry were inconclusive for lymphoma/leukemia, but oligoclonal bands were present. Serum aquaporin-4 (AQP-4) antibodies were negative. MR spectroscopy demonstrated NAA reduction, mild lipid lactate peak, and relative reduction of choline on the side of the lesion, favoring demyelination. She received 5-days of intravenous methylprednisolone, followed by 7 sessions of plasma exchange without clinical improvement. Stereotactic biopsy of the right thalamic lesion revealed diffuse large B-cell lymphoma. PCNSL can mimic a demyelinating process early on, as steroid treatment could disrupt B-cell lymphoma cells, thus masking the correct diagnosis.


Rare Tumors ◽  
2015 ◽  
Vol 7 (4) ◽  
pp. 160-162 ◽  
Author(s):  
Pooja Advani ◽  
Jason Starr ◽  
Abhisek Swaika ◽  
Liuyan Jiang ◽  
Yushi Qiu ◽  
...  

Blood ◽  
2008 ◽  
Vol 111 (6) ◽  
pp. 3200-3210 ◽  
Author(s):  
Han W. Tun ◽  
David Personett ◽  
Karen A. Baskerville ◽  
David M. Menke ◽  
Kurt A. Jaeckle ◽  
...  

Abstract Primary central nervous system (CNS) lymphoma (PCNSL) is a diffuse large B-cell lymphoma (DLBCL) confined to the CNS. A genome-wide gene expression comparison between PCNSL and non-CNS DLBCL was performed, the latter consisting of both nodal and extranodal DLBCL (nDLBCL and enDLBCL), to identify a “CNS signature.” Pathway analysis with the program SigPathway revealed that PCNSL is characterized notably by significant differential expression of multiple extracellular matrix (ECM) and adhesion-related pathways. The most significantly up-regulated gene is the ECM-related osteopontin (SPP1). Expression at the protein level of ECM-related SPP1 and CHI3L1 in PCNSL cells was demonstrated by immunohistochemistry. The alterations in gene expression can be interpreted within several biologic contexts with implications for PCNSL, including CNS tropism (ECM and adhesion-related pathways, SPP1, DDR1), B-cell migration (CXCL13, SPP1), activated B-cell subtype (MUM1), lymphoproliferation (SPP1, TCL1A, CHI3L1), aggressive clinical behavior (SPP1, CHI3L1, MUM1), and aggressive metastatic cancer phenotype (SPP1, CHI3L1). The gene expression signature discovered in our study may represent a true “CNS signature” because we contrasted PCNSL with wide-spectrum non-CNS DLBCL on a genomic scale and performed an in-depth bioinformatic analysis.


2020 ◽  
Author(s):  
Haoyu Ruan ◽  
Zhe Wang ◽  
Yue Zhai ◽  
Ying Xu ◽  
Linyu Pi ◽  
...  

AbstractDiffuse large B-cell lymphoma (DLBCL) is the predominant type of central nervous system lymphoma (CNSL) including primary CNSL and secondary CNSL. Diffuse large B cells in cerebrospinal fluid (CSF-DLBCs) have offered great promise for the diagnostics and therapeutics of CNSL leptomeningeal involvement. To explore the distinct phenotypic states of CSF-DLBCs, we analyzed the transcriptomes of 902 CSF-DLBCs from six CNSL-DLBCL patients using single-cell RNA sequencing technology. We defined CSF-DLBCs based on abundant expression of B-cell markers, as well as the enrichment of cell proliferation and energy metabolism pathways. CSF-DLBCs within individual patients exhibited monoclonality with similar variable region of light chains (VL) expression. It is noteworthy that we observed some CSF-DLBCs have double classes of VL (lambda and kappa) transcripts. We identified substantial heterogeneity in CSF-DLBCs, and found significantly greater among-patient heterogeneity compared to among-cell heterogeneity within a given patient. The transcriptional heterogeneity across CSF-DLBCs is manifested in cell cycle state and cancer-testis antigens expression. Our results will provide insight into the mechanism research and new diagnostic direction of CNSL-DLBCL leptomeningeal involvement.


2020 ◽  
Vol 18 (11) ◽  
pp. 1571-1578
Author(s):  
Matthias Holdhoff ◽  
Maciej M. Mrugala ◽  
Christian Grommes ◽  
Thomas J. Kaley ◽  
Lode J. Swinnen ◽  
...  

Primary central nervous system lymphomas (PCNSLs) are rare cancers of the central nervous system (CNS) and are predominantly diffuse large B-cell lymphomas of the activated B-cell (ABC) subtype. They typically present in the sixth and seventh decade of life, with the highest incidence among patients aged >75 years. Although many different regimens have demonstrated efficacy in newly diagnosed and relapsed or refractory PCNSL, there have been few randomized prospective trials, and most recommendations and treatment decisions are based on single-arm phase II trials or even retrospective studies. High-dose methotrexate (HD-MTX; 3–8 g/m2) is the backbone of preferred standard induction regimens. Various effective regimens with different toxicity profiles can be considered that combine other chemotherapies and/or rituximab with HD-MTX, but there is currently no consensus for a single preferred regimen. There is controversy about the role of various consolidation therapies for patients who respond to HD-MTX–based induction therapy. For patients with relapsed or refractory PCNSL who previously experienced response to HD-MTX, repeat treatment with HD-MTX–based therapy can be considered depending on the timing of recurrence. Other more novel and less toxic regimens have been developed that show efficacy in recurrent disease, including ibrutinib, or lenalidomide ± rituximab. There is uniform agreement to delay or avoid whole-brain radiation therapy due to concerns for significant neurotoxicity if a reasonable systemic treatment option exists. This article aims to provide a clinically practical approach to PCNSL, including special considerations for older patients and those with impaired renal function. The benefits and risks of HD-MTX or high-dose chemotherapy with autologous stem cell transplantation versus other, better tolerated strategies are also discussed. In all settings, the preferred treatment is always enrollment in a clinical trial if one is available.


2019 ◽  
Vol 25 (4) ◽  
pp. 239-242
Author(s):  
Asuman Ali ◽  
Cemile Haki ◽  
Fatma Öz Atalay ◽  
Ramazan Yalçın

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