Publications by authors named "Hiroo Ueno"

53 Publications

Clonal evidence for the development of neuroblastoma with extensive copy-neutral loss of heterozygosity arising in a mature teratoma.

Cancer Sci 2021 May 2. Epub 2021 May 2.

Department of Pediatrics, St. Luke's International Hospital, Tokyo, Japan.

Mature teratomas are usually benign tumors that rarely undergo malignant transformation. We report an advanced neuroblastoma arising in a mature teratoma of the ovary. Whole-exome sequencing identified extensive copy-neutral loss of heterozygosity (LOH) in both neuroblastoma and teratoma elements, suggesting that the neuroblastoma evolved from the teratoma. In addition, several truncating germline heterozygous variants in tumor suppressor genes, including RBL2 and FBXW12, became homozygous as a result of LOH. Collectively, we speculate that extensive LOH in teratoma cells may force heterozygous germline variants to become homozygous, which, in turn, may contribute to the development of neuroblastoma with the acquisition of additional chromosomal changes.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/cas.14931DOI Listing
May 2021

Landscape of driver mutations and their clinical impacts in pediatric B-cell precursor acute lymphoblastic leukemia.

Blood Adv 2020 10;4(20):5165-5173

Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan.

Recent genetic studies using high-throughput sequencing have disclosed genetic alterations in B-cell precursor acute lymphoblastic leukemia (B-ALL). However, their effects on clinical outcomes have not been fully investigated. To address this, we comprehensively examined genetic alterations and their prognostic impact in a large series of pediatric B-ALL cases. We performed targeted capture sequencing in a total of 1003 pediatric patients with B-ALL from 2 Japanese cohorts. Transcriptome sequencing (n = 116) and/or array-based gene expression analysis (n = 120) were also performed in 203 (84%) of 243 patients who were not categorized into any disease subgroup by panel sequencing or routine reverse transcription polymerase chain reaction analysis for major fusions in B-ALL. Our panel sequencing identified novel recurrent mutations in 2 genes (CCND3 and CIC), and both had positive correlations with ETV6-RUNX1 and hypodiploid ALL, respectively. In addition, positive correlations were also newly reported between TCF3-PBX1 ALL with PHF6 mutations. In multivariate Cox proportional hazards regression models for overall survival, TP53 mutation/deletion, hypodiploid, and MEF2D fusions were selected in both cohorts. For TP53 mutations, the negative effect on overall survival was confirmed in an independent external cohort (n = 466). TP53 mutation was frequently found in IGH-DUX4 (5 of 57 [9%]) ALL, with 4 cases having 17p LOH and negatively affecting overall survival therein, whereas TP53 mutation was not associated with poor outcomes among NCI (National Cancer Institute) standard risk (SR) patients. A conventional treatment approach might be enough, and further treatment intensification might not be necessary, for patients with TP53 mutations if they are categorized into NCI SR.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/bloodadvances.2019001307DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7594377PMC
October 2020

Fusion partner-specific mutation profiles and KRAS mutations as adverse prognostic factors in MLL-rearranged AML.

Blood Adv 2020 10;4(19):4623-4631

Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

Mixed-lineage leukemia (MLL) gene rearrangements are among the most frequent chromosomal abnormalities in acute myeloid leukemia (AML). MLL fusion patterns are associated with the patient's prognosis; however, their relationship with driver mutations is unclear. We conducted sequence analyses of 338 genes in pediatric patients with MLL-rearranged (MLL-r) AML (n = 56; JPLSG AML-05 study) alongside data from the TARGET study's pediatric cohorts with MLL-r AML (n = 104), non-MLL-r AML (n = 581), and adult MLL-r AML (n = 81). KRAS mutations were most frequent in pediatric patients with high-risk MLL fusions (MLL-MLLLT10, MLL-MLLT4, and MLL-MLLT1). Pediatric patients with MLL-r AML (n = 160) and a KRAS mutation (KRAS-MT) had a significantly worse prognosis than those without a KRAS mutation (KRAS-WT) (5-year event-free survival [EFS]: 51.8% vs 18.3%, P < .0001; 5-year overall survival [OS]: 67.3% vs 44.3%, P = .003). The adverse prognostic impact of KRAS mutations was confirmed in adult MLL-r AML. KRAS mutations were associated with adverse prognoses in pediatric patients with both high-risk (MLLT10+MLLT4+MLLT1; n = 60) and intermediate-to-low-risk (MLLT3+ELL+others; n = 100) MLL fusions. The prognosis did not differ significantly between patients with non-MLL-r AML with KRAS-WT or KRAS-MT. Multivariate analysis showed the presence of a KRAS mutation to be an independent prognostic factor for EFS (hazard ratio [HR], 2.21; 95% confidence interval [CI], 1.35-3.59; P = .002) and OS (HR, 1.85; 95% CI, 1.01-3.31; P = .045) in MLL-r AML. The mutation is a distinct adverse prognostic factor in MLL-r AML, regardless of risk subgroup, and is potentially useful for accurate treatment stratification. This trial was registered at the UMIN (University Hospital Medical Information Network) Clinical Trials Registry (UMIN-CTR; http://www.umin.ac.jp/ctr/index.htm) as #UMIN000000511.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/bloodadvances.2020002457DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7556160PMC
October 2020

Generation of a p16 Reporter Mouse and Its Use to Characterize and Target p16 Cells In Vivo.

Cell Metab 2020 11 18;32(5):814-828.e6. Epub 2020 Sep 18.

Division of Molecular Regulation of Inflammatory and Immune Diseases, Research Institute of Biomedical Sciences, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-0022, Japan.

Cell senescence plays a key role in age-associated organ dysfunction, but the in vivo pathogenesis is largely unclear. Here, we generated a p16-Cre-tdTomato mouse model to analyze the in vivo characteristics of p16 cells at a single-cell level. We found tdTomato-positive p16 cells detectable in all organs, which were enriched with age. We also found that these cells failed to proliferate and had half-lives ranging from 2.6 to 4.2 months, depending on the tissue examined. Single-cell transcriptomics in the liver and kidneys revealed that p16 cells were present in various cell types, though most dominant in hepatic endothelium and in renal proximal and distal tubule epithelia, and that these cells exhibited heterogeneous senescence-associated phenotypes. Further, elimination of p16 cells ameliorated nonalcoholic steatohepatitis-related hepatic lipidosis and immune cell infiltration. Our new mouse model and single-cell analysis provide a powerful resource to enable the discovery of previously unidentified senescence functions in vivo.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.cmet.2020.09.006DOI Listing
November 2020

Whole-Exome Sequencing-Based Approach for Germline Mutations in Patients with Inborn Errors of Immunity.

J Clin Immunol 2020 07 6;40(5):729-740. Epub 2020 Jun 6.

Department of Pediatrics, Tokyo Medical and Dental University (TMDU), 1-5-45, Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.

Purpose: Owing to recent technological advancements, using next-generation sequencing (NGS) and the accumulation of clinical experiences worldwide, more than 420 genes associated with inborn errors of immunity (IEI) have been identified, which exhibit large genotypic and phenotypic variations. Consequently, NGS-based comprehensive genetic analysis, including whole-exome sequencing (WES), have become more valuable in the clinical setting and have contributed to earlier diagnosis, improved treatment, and prognosis. However, these approaches have the following disadvantages that need to be considered: a relatively low diagnostic rate, high cost, difficulties in the interpretation of each variant, and the risk of incidental findings. Thus, the objective of this study is to review our WES results of a large number of patients with IEI and to elucidate patient characteristics, which are related to the positive WES result.

Methods: We performed WES for 136 IEI patients with negative conventional screening results for candidate genes and classified these variants depending on validity of their pathogenicity.

Results: We identified disease-causing pathogenic mutations in 36 (26.5%) of the patients which were found in known IEI-causing genes. Although the overall diagnostic rate was not high and was not apparently correlated with the clinical subcategories and severity, we revealed that earlier onset with longer duration of diseases were associated with positive WES results, especially in pediatric cases.

Conclusions: Most of the disease-causing germline mutations were located in the known IEI genes which could be predicted using patients' clinical characteristics. These results may be useful when considering appropriate genetic approaches in the clinical setting.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10875-020-00798-3DOI Listing
July 2020

Genomic analysis of multiple myeloma using targeted capture sequencing in the Japanese cohort.

Br J Haematol 2020 12 9;191(5):755-763. Epub 2020 May 9.

Department of Hematology and Oncology, Nagoya City University Graduate School of Medical Sciences, Japan.

Previous genomic studies have revealed the genomic landscape of myeloma cells. Although some of the genomic abnormalities shown are believed to be correlated to the molecular pathogenesis of multiple myeloma and/or clinical outcome, these correlations are not fully understood. The aim of this study is to elucidate the correlation between genomic abnormalities and clinical characteristics by targeted capture sequencing in the Japanese multiple myeloma cohort. We analysed 154 patients with newly diagnosed multiple myeloma. The analysis revealed that the study cohort consisted of a less frequent hyperdiploid subtype (37·0%) with relatively high frequencies of KRAS mutation (36·4%) and IGH-CCND1 translocation (26·6%) compared with previous reports. Moreover, our targeted capture sequencing strategy was able to detect rare IGH-associated chromosomal translocations, such as IGH-CCND2 and IGH-MAFA. Interestingly, all 10 patients harboured MAX mutations accompanied by 14q23 deletion. The patients with del(17p) exhibited an unfavourable clinical outcome, and the presence of KRAS mutation was associated with shorter survival in patients with multiple myeloma, harbouring IGH-CCND1. Thus, our study provides a detailed landscape of genomic abnormalities, which may have potential clinical application for patients with multiple myeloma.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1111/bjh.16720DOI Listing
December 2020

Molecular pathogenesis of progression to myeloid leukemia from TET-insufficient status.

Blood Adv 2020 03;4(5):845-854

Department of Hematology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.

Loss-of-function mutations in ten-eleven translocation-2 (TET2) are recurrent events in acute myeloid leukemia (AML) as well as in preleukemic hematopoietic stem cells (HSCs) of age-related clonal hematopoiesis. TET3 mutations are infrequent in AML, but the level of TET3 expression in HSCs has been found to decline with age. We examined the impact of gradual decrease of TET function in AML development by generating mice with Tet deficiency at various degrees. Tet2f/f and Tet3f/f mice were crossed with mice expressing Mx1-Cre to generate Tet2f/wtTet3f/fMx-Cre+ (T2ΔT3), Tet2f/fTet3f/wtMx-Cre+ (ΔT2T3), and Tet2f/fTet3f/fMx-Cre+ (ΔT2ΔT3) mice. All ΔT2ΔT3 mice died of aggressive AML at a median survival of 10.7 weeks. By comparison, T2ΔT3 and ΔT2T3 mice developed AML at longer latencies, with a median survival of ∼27 weeks. Remarkably, all 9 T2ΔT3 and 8 ΔT2T3 mice with AML showed inactivation of the remaining nontargeted Tet2 or Tet3 allele, respectively, owing to exonic loss in either gene or stop-gain mutations in Tet3. Recurrent mutations other than Tet3 were not noted in any mice by whole-exome sequencing. Spontaneous inactivation of residual Tet2 or Tet3 alleles is a recurrent genetic event during the development of AML with Tet insufficiency.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/bloodadvances.2019001324DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7065477PMC
March 2020

Molecular heterogeneity in peripheral T-cell lymphoma, not otherwise specified revealed by comprehensive genetic profiling.

Leukemia 2019 12 15;33(12):2867-2883. Epub 2019 May 15.

Department of Hematology, Kobe City Medical Center General Hospital, Kobe, Japan.

Peripheral T-cell lymphoma, not otherwise specified (PTCL, NOS) is a diagnosis of exclusion, being the most common entity in mature T-cell neoplasms, and its molecular pathogenesis remains significantly understudied. Here, combining whole-exome and targeted-capture sequencing, gene-expression profiling, and immunohistochemical analysis of tumor samples from 133 cases, we have delineated the entire landscape of somatic alterations, and discovered frequently affected driver pathways in PTCL, NOS, with and without a T-follicular helper (TFH) cell phenotype. In addition to previously reported mutational targets, we identified a number of novel recurrently altered genes, such as KMT2C, SETD1B, YTHDF2, and PDCD1. We integrated these genetic drivers using hierarchical clustering and identified a previously undescribed molecular subtype characterized by TP53 and/or CDKN2A mutations and deletions in non-TFH PTCL, NOS. This subtype exhibited different prognosis and unique genetic features associated with extensive chromosomal instability, which preferentially affected molecules involved in immune escape and transcriptional regulation, such as HLA-A/B and IKZF2. Taken together, our findings provide novel insights into the molecular pathogenesis of PTCL, NOS by highlighting their genetic heterogeneity. These results should help to devise a novel molecular classification of PTCLs and to exploit a new therapeutic strategy for this group of aggressive malignancies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41375-019-0473-1DOI Listing
December 2019

Intimal regeneration after coronary endarterectomy and onlay grafting in coronary artery bypass grafting.

Gen Thorac Cardiovasc Surg 2019 Aug 21;67(8):677-683. Epub 2019 Feb 21.

Department of Stem Cell Pathology, Kansai Medical University, Osaka, Japan.

Objectives: Coronary onlay grafting, with or without endarterectomy, has been widely used for the treatment of diffuse lesions. Recent studies have demonstrated excellent long-term patency and favorable remodeling of onlay anastomosis; however, the underlying mechanisms remain unknown. Here, we describe the mechanism of intimal regeneration based on postmortem pathological evaluation of a patient who had undergone onlay grafting with coronary endarterectomy.

Methods: The onlay anastomosis was analyzed using a combination of immunohistological stainings, namely, H&E, vimentin, α-SMA, factor VIII, and Ki-67, to identify the source and mechanism of intimal regeneration after onlay grafting with endarterectomy.

Results: Our results suggest that the regenerated endothelium derives from the smooth muscle cells of the endarterectomized media of the coronary artery and that it circumferentially covers the internal lumen of the arterial graft.

Conclusions: Intimal regeneration, derived from the smooth muscle cells of the endarterectomized coronary artery that proliferate toward the graft lumen, may be a key mechanism that underlies the observed favorable remodeling after onlay grafting during coronary endarterectomy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11748-019-01083-wDOI Listing
August 2019

Novel neuroblastoma amplified sequence () mutations in a Japanese boy with fever-triggered recurrent acute liver failure.

Hum Genome Var 2019 7;6. Epub 2019 Jan 7.

1Department of Pediatrics, Kawasaki Medical School, Okayama, 701-0192 Japan.

Biallelic mutations in the neuroblastoma amplified sequence () gene have been reported to cause two different clinical spectra: short stature with optic nerve atrophy and Pelger-Huët anomaly (SOPH) syndrome and infantile liver failure syndrome 2 (ILFS2). Here, we describe a case of a 3-year-old Japanese boy who presented with fever-triggered recurrent acute liver failure (ALF). The clinical characteristics were considerable elevation of liver enzymes, severe coagulopathy, and acute renal failure. In addition to the liver phenotype, he had short stature and Pelger-Huët anomaly in the peripheral granulocytes. Whole-exome and Sanger sequencing of the patient and his parents revealed that he carried novel compound heterozygous missense mutations in , c.1018G>C (p.Gly340Arg) and c.2674 G>T (p.Val892Phe). Both mutations affect evolutionarily conserved amino acid residues and are predicted to be highly damaging. Immunoblot analysis of the patient's skin fibroblasts showed a normal NBAS protein level but a reduced protein level of its interaction partner, p31, involved in Golgi-to-endoplasmic reticulum retrograde vesicular trafficking. We recommend gene analysis in children with unexplained fever-triggered recurrent ALF or liver dysfunction. Early antipyretic therapy may prevent further episodes of ALF.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41439-018-0035-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6323122PMC
January 2019

Discovery of a Small Molecule to Increase Cardiomyocytes and Protect the Heart After Ischemic Injury.

JACC Basic Transl Sci 2018 Oct 12;3(5):639-653. Epub 2018 Nov 12.

Department of Cardiovascular Medicine, The University of Tokyo Hospital, Tokyo, Japan.

Accumulating data suggest that new cardiomyocytes in adults are generated from existing cardiomyocytes throughout life. To enhance the endogenous cardiac regeneration, we performed chemical screenings to identify compounds that activate pro-proliferative YES-associated protein and transcriptional enhancer factor domain activities in cardiomyocytes. We synthesized a novel fluorine-containing TT-10 (CHFNOS) from the biologically hit compound. TT-10 promoted cardiomyocyte proliferation and simultaneously exerted antioxidant and antiapoptotic effects in vitro. TT-10 treatment in mice ameliorated myocardial infarction-induced cardiac dysfunction at least in part via enhancing clonal expansion of existing cardiomyocytes with nuclear YES-associated protein expression. Stimulating cardiomyocyte proliferation and/or protection with TT-10 might complement current therapies for myocardial infarction.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jacbts.2018.07.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6234526PMC
October 2018

Recurrent mutations in -rearranged acute myeloid leukemia.

Blood Adv 2018 11;2(21):2879-2889

Division of Leukemia and Lymphoma, Children's Cancer Center, National Center for Child Health and Development, Tokyo, Japan.

In acute myeloid leukemia (AML), () rearrangements are among the most frequent chromosomal abnormalities; however, knowledge of the genetic landscape of -rearranged AML is limited. In this study, we performed whole-exome sequencing (n = 9) and targeted sequencing (n = 56) of samples from pediatric -rearranged AML patients enrolled in the Japanese Pediatric Leukemia/Lymphoma Study Group AML-05 study. Additionally, we analyzed 105 pediatric t(8;21) AML samples and 30 adult -rearranged AML samples. RNA-sequencing data from 31 patients published in a previous study were also reanalyzed. As a result, we identified 115 mutations in pediatric -rearranged AML patients (2.1 mutations/patient), with mutations in signaling pathway genes being the most frequently detected (60.7%). Mutations in genes associated with epigenetic regulation (21.4%), transcription factors (16.1%), and the cohesin complex (8.9%) were also commonly detected. Novel mutations were identified in 5 pediatric -rearranged AML patients (8.9%) and 2 adult -rearranged AML patients (3.3%). Recurrent mutations of (n = 3, 2.9%) and (n = 8, 7.6%) were found in pediatric t(8;21) AML patients, whereas no mutations were found, suggesting that D-type cyclins exhibit a subtype-specific mutation pattern in AML. Treatment of -rearranged AML cell lines with CDK4/6 inhibitors (abemaciclib and palbociclib) blocked G1 to S phase cell-cycle progression and impaired proliferation. Pediatric -rearranged AML patients with coexisting mutations (n = 16) had significantly reduced relapse-free survival and overall survival compared with those without coexisting mutations (n = 9) ( = .048 and .046, respectively). These data provide insights into the genetics of -rearranged AML and suggest therapeutic strategies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/bloodadvances.2018019398DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6234363PMC
November 2018

Two siblings with familial neuroblastoma with distinct clinical phenotypes harboring an ALK germline mutation.

Genes Chromosomes Cancer 2018 12 22;57(12):665-669. Epub 2018 Oct 22.

Department of Pediatrics, Hirosaki University Graduate School of Medicine, Hirosaki, Japan.

The authors report two siblings with familial neuroblastoma with a germline R1275Q mutation of the tyrosine kinase domain of ALK. Whole exome sequencing and copy number variation assay were performed to investigate genetic alterations in the two cases. No common somatic mutations or gene polymorphisms related to the tumorigenesis of neuroblastoma were detected. A distinct pattern involving both segmental chromosomal alteration and MYCN amplification was detected. The diversity of biological behavior of familial neuroblastoma harboring a germline ALK mutation may depend on conventional prognostic factors, such as segmental chromosomal alterations and MYCN amplification, rather than additional acquired mutations.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/gcc.22676DOI Listing
December 2018

Molecular pathogenesis of disease progression in MLL-rearranged AML.

Leukemia 2019 03 12;33(3):612-624. Epub 2018 Sep 12.

Department of Pathology and Tumor Biology, Kyoto University, Kyoto, Japan.

Leukemic relapse is frequently accompanied by progressively aggressive clinical course. To understand the molecular mechanism of leukemic relapse, MLL/AF9-transformed mouse leukemia cells were serially transplanted in C57BL/6 mice (N = 96) by mimicking repeated recurrences, where mutations were monitored by exome sequencing (N = 42). The onset of leukemia was progressively promoted with advanced transplants, during which increasing numbers of somatic mutations were acquired (P < 0.005). Among these, mutations in Ptpn11 (p.G60R) and Braf (p.V637E) corresponded to those identified in human MLL-AML, while recurrent mutations affecting Msn (p.R295C) were observed only in mouse but not in human MLL-AML. Another mutated gene of interest was Gnb2 which was reported to be recurrently mutated in various hematological neoplasms. Gnb2 mutations (p.G77R) were significantly increased in clone size (P = 0.007) and associated with earlier leukemia onset (P = 0.011). GNB2 transcripts were significantly upregulated in human MLL-AML compared to MLL-negative AML (P < 0.05), which was supported by significantly increased Gnb2 transcript induced by MLL/AF9 overexpression (P < 0.001). In in vivo model, both mutation and overexpression of GNB2 caused leukemogenesis, and downregulation of GNB2 expression reduced proliferative potential and survival benefit, suggesting a driver role of GNB2. In conclusion, alterations of driver genes over time may play an important role in the progression of MLL-AML.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41375-018-0253-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6462875PMC
March 2019

Early detection and evolution of preleukemic clones in therapy-related myeloid neoplasms following autologous SCT.

Blood 2018 04 8;131(16):1846-1857. Epub 2018 Jan 8.

Department of Laboratory Medicine, Laboratory of Hematology, Radboud University Medical Center, Nijmegen, The Netherlands.

Therapy-related myeloid neoplasms (tMNs) are severe adverse events that can occur after treatment with autologous hematopoietic stem cell transplantation (ASCT). This study aimed to investigate the development of tMNs following ASCT at the molecular level by whole-exome sequencing (WES) and targeted deep sequencing (TDS) in sequential (pre-) tMN samples. WES identified a significantly higher number of mutations in tMNs as compared with de novo myelodysplastic syndrome (MDS) (median 27 vs 12 mutations; = .001). The mutations found in tMNs did not carry a clear aging-signature, unlike the mutations found in de novo MDS, indicating a different mutational mechanism. In some patients, tMN mutations were identified in both myeloid and T cells, suggesting that tMNs may originate from early hematopoietic stem cells (HSCs). However, the mutational spectra of tMNs and the preceding malignancies did not overlap, excluding common ancestry for these malignancies. By use of TDS, tMN mutations were identified at low variant allele frequencies (VAFs) in transplant material in 70% of the patients with tMNs. Reconstruction of clonal patterns based on VAFs revealed that premalignant clones can be present more than 7 years preceding a tMN diagnosis, a finding that was confirmed by immunohistochemistry on bone marrow biopsies. Our results indicate that tMN development after ASCT originates in HSCs bearing (pre-)tMN mutations that are present years before disease onset and that post-ASCT treatment can influence the selection of these clones. Early detection of premalignant clones and monitoring of their evolutionary trajectory may help to predict the development of tMNs and guide early intervention in the future.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/blood-2017-09-805879DOI Listing
April 2018

Genetic heterogeneity of uncharacterized childhood autoimmune diseases with lymphoproliferation.

Pediatr Blood Cancer 2018 Feb 29;65(2). Epub 2017 Sep 29.

Department of Pediatrics and Developmental Biology, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.

Autoimmune diseases in children are rare and can be difficult to diagnose.  Single causative genes have been identified for some pediatric autoimmune diseases. Such orphan diseases may not be diagnosed properly due to the variability of patients' phenotypes. Guidelines for the diagnostic process need to be developed. Fifteen patients with uncharacterized childhood autoimmune diseases with lymphoproliferation that had negative testing for autoimmune lymphoproliferative syndrome were subjected to whole-exome sequencing to identify genes associated with these conditions. Five causative genes, CTLA4, STAT3, TNFAIP3, IKZF1, and PSTPIP1, were identified. These genes should be considered as candidates for uncharacterized childhood autoimmune diseases with lymphoproliferation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1002/pbc.26831DOI Listing
February 2018

Intestinal stem cells contribute to the maturation of the neonatal small intestine and colon independently of digestive activity.

Sci Rep 2017 08 31;7(1):9891. Epub 2017 Aug 31.

Department of Stem Cell Pathology, Kansai Medical University, 2-5-1 Shin-machi, Hirakata, Osaka, 573-1010, Japan.

The murine intestine, like that of other mammalians, continues to develop after birth until weaning; however, whether this occurs in response to an intrinsic developmental program or food intake remains unclear. Here, we report a novel system for the allotransplantation of small intestine and colon harvested from Lgr5 ; Rosa26 mice immediately after birth into the subrenal capsule of wild-type mice. By histological and immunohistochemical analysis, the developmental process of transplanted small intestine and colon was shown to be comparable with that of the native tissues: mature intestines equipped with all cell types were formed, indicating that these organs do not require food intake for development. The intestinal stem cells in transplanted tissues were shown to self-renew and produce progeny, resulting in the descendants of the stem cells occupying the crypt-villus unit of the small intestine or the whole crypt of the colon. Collectively, these findings indicate that neonatal intestine development follows an intrinsic program even in the absence of food stimuli.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-017-09927-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5578958PMC
August 2017

Recurrent SPI1 (PU.1) fusions in high-risk pediatric T cell acute lymphoblastic leukemia.

Nat Genet 2017 Aug 3;49(8):1274-1281. Epub 2017 Jul 3.

Department of Pediatrics, Kyoto Prefectural University of Medicine, Graduate School of Medical Science, Kyoto, Japan.

The outcome of treatment-refractory and/or relapsed pediatric T cell acute lymphoblastic leukemia (T-ALL) is extremely poor, and the genetic basis for this is not well understood. Here we report comprehensive profiling of 121 cases of pediatric T-ALL using transcriptome and/or targeted capture sequencing, through which we identified new recurrent gene fusions involving SPI1 (STMN1-SPI1 and TCF7-SPI1). Cases positive for fusions involving SPI1 (encoding PU.1), accounting for 3.9% (7/181) of the examined pediatric T-ALL cases, showed a double-negative (DN; CD4CD8) or CD8 single-positive (SP) phenotype and had uniformly poor overall survival. These cases represent a subset of pediatric T-ALL distinguishable from the known T-ALL subsets in terms of expression of genes involved in T cell precommitment, establishment of T cell identity, and post-β-selection maturation and with respect to mutational profile. PU.1 fusion proteins retained transcriptional activity and, when constitutively expressed in mouse stem/progenitor cells, induced cell proliferation and resulted in a maturation block. Our findings highlight a unique role of SPI1 fusions in high-risk pediatric T-ALL.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/ng.3900DOI Listing
August 2017

Identification of mouse cochlear progenitors that develop hair and supporting cells in the organ of Corti.

Nat Commun 2017 05 11;8:15046. Epub 2017 May 11.

Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York 10029, USA.

The adult mammalian cochlear sensory epithelium houses two major types of cells, mechanosensory hair cells and underlying supporting cells, and lacks regenerative capacity. Recent evidence indicates that a subset of supporting cells can spontaneously regenerate hair cells after ablation only within the first week postparturition. Here in vivo clonal analysis of mouse inner ear cells during development demonstrates clonal relationship between hair and supporting cells in sensory organs. We report the identification in mouse of a previously unknown population of multipotent stem/progenitor cells that are capable of not only contributing to the hair and supporting cells but also to other cell types, including glia, in cochlea undergoing development, maturation and repair in response to damage. These multipotent progenitors originate from Eya1-expressing otic progenitors. Our findings also provide evidence for detectable regenerative potential in the postnatal cochlea beyond 1 week of age.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/ncomms15046DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5437288PMC
May 2017

Non-equivalence of Wnt and R-spondin ligands during Lgr5 intestinal stem-cell self-renewal.

Nature 2017 05 3;545(7653):238-242. Epub 2017 May 3.

Department of Molecular and Cellular Physiology, Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California 94305, USA.

The canonical Wnt/β-catenin signalling pathway governs diverse developmental, homeostatic and pathological processes. Palmitoylated Wnt ligands engage cell-surface frizzled (FZD) receptors and LRP5 and LRP6 co-receptors, enabling β-catenin nuclear translocation and TCF/LEF-dependent gene transactivation. Mutations in Wnt downstream signalling components have revealed diverse functions thought to be carried out by Wnt ligands themselves. However, redundancy between the 19 mammalian Wnt proteins and 10 FZD receptors and Wnt hydrophobicity have made it difficult to attribute these functions directly to Wnt ligands. For example, individual mutations in Wnt ligands have not revealed homeostatic phenotypes in the intestinal epithelium-an archetypal canonical, Wnt pathway-dependent, rapidly self-renewing tissue, the regeneration of which is fueled by proliferative crypt Lgr5 intestinal stem cells (ISCs). R-spondin ligands (RSPO1-RSPO4) engage distinct LGR4-LGR6, RNF43 and ZNRF3 receptor classes, markedly potentiate canonical Wnt/β-catenin signalling, and induce intestinal organoid growth in vitro and Lgr5 ISCs in vivo. However, the interchangeability, functional cooperation and relative contributions of Wnt versus RSPO ligands to in vivo canonical Wnt signalling and ISC biology remain unknown. Here we identify the functional roles of Wnt and RSPO ligands in the intestinal crypt stem-cell niche. We show that the default fate of Lgr5 ISCs is to differentiate, unless both RSPO and Wnt ligands are present. However, gain-of-function studies using RSPO ligands and a new non-lipidated Wnt analogue reveal that these ligands have qualitatively distinct, non-interchangeable roles in ISCs. Wnt proteins are unable to induce Lgr5 ISC self-renewal, but instead confer a basal competency by maintaining RSPO receptor expression that enables RSPO ligands to actively drive and specify the extent of stem-cell expansion. This functionally non-equivalent yet cooperative interaction between Wnt and RSPO ligands establishes a molecular precedent for regulation of mammalian stem cells by distinct priming and self-renewal factors, with broad implications for precise control of tissue regeneration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/nature22313DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5641471PMC
May 2017

Genetic abnormalities in myelodysplasia and secondary acute myeloid leukemia: impact on outcome of stem cell transplantation.

Blood 2017 04 21;129(17):2347-2358. Epub 2017 Feb 21.

Department of Advanced Diagnosis, Clinical Research Center, Nagoya Medical Center, Nagoya, Japan.

Genetic alterations, including mutations and copy-number alterations, are central to the pathogenesis of myelodysplastic syndromes and related diseases (myelodysplasia), but their roles in allogeneic stem cell transplantation have not fully been studied in a large cohort of patients. We enrolled 797 patients who had been diagnosed with myelodysplasia at initial presentation and received transplantation via the Japan Marrow Donor Program. Targeted-capture sequencing was performed to identify mutations in 69 genes, together with copy-number alterations, whose effects on transplantation outcomes were investigated. We identified 1776 mutations and 927 abnormal copy segments among 617 patients (77.4%). In multivariate modeling using Cox proportional-hazards regression, genetic factors explained 30% of the total hazards for overall survival; clinical characteristics accounted for 70% of risk. and RAS-pathway mutations, together with complex karyotype (CK) as detected by conventional cytogenetics and/or sequencing-based analysis, negatively affected posttransplant survival independently of clinical factors. Regardless of disease subtype, -mutated patients with CK were characterized by unique genetic features and associated with an extremely poor survival with frequent early relapse, whereas outcomes were substantially better in -mutated patients without CK. By contrast, the effects of RAS-pathway mutations depended on disease subtype and were confined to myelodysplastic/myeloproliferative neoplasms (MDS/MPNs). Our results suggest that and RAS-pathway mutations predicted a dismal prognosis, when associated with CK and MDS/MPNs, respectively. However, for patients with mutated or CK alone, long-term survival could be obtained with transplantation. Clinical sequencing provides vital information for accurate prognostication in transplantation.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1182/blood-2016-12-754796DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5409449PMC
April 2017

Intestinal cancer stem cells marked by Bmi1 or Lgr5 expression contribute to tumor propagation via clonal expansion.

Sci Rep 2017 02 8;7:41838. Epub 2017 Feb 8.

Department of Stem Cell Pathology, Kansai Medical University, 2-5-1 Shin-machi, Hirakata, Osaka 573-1010, Japan.

Although the existence of cancer stem cells in intestine tumors has been suggested, direct evidence has not been yet provided. Here, we showed, using the multicolor lineage-tracing method and mouse models of intestinal adenocarcinoma and adenoma that Bmi1- or Lgr5- positive tumorigenic cells clonally expanded in proliferating tumors. At tumor initiation and during tumor propagation in the colon, the descendants of Lgr5-positive cells clonally proliferated to form clusters. Clonal analysis using ubiquitous multicolor lineage tracing revealed that colon tumors derived from Lgr5-positive cells were monoclonal in origin but eventually merged with neighboring tumors, producing polyclonal tumors at the later stage. In contrast, the origin of small intestine tumors was likely polyclonal, and during cancer progression some clones were eliminated, resulting in the formation of monoclonal tumors, which could merge similar to colon tumors. These results suggest that in proliferating intestinal neoplasms, Bmi1- or Lgr5-positive cells represent a population of cancer stem cells, whereas Lgr5-positive cells also function as cells-of-origin for intestinal tumors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/srep41838DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5296906PMC
February 2017

Bmi1-positive cells in the lingual epithelium could serve as cancer stem cells in tongue cancer.

Sci Rep 2016 12 22;6:39386. Epub 2016 Dec 22.

Department of Stem Cell Pathology, Kansai Medical University, 2-5-1 Shin-machi, Hirakata, Osaka 573-1010, Japan.

We recently reported that the polycomb complex protein Bmi1 is a marker for lingual epithelial stem cells (LESCs), which are involved in the long-term maintenance of lingual epithelial tissue in the physiological state. However, the precise role of LESCs in generating tongue tumors and Bmi1-positive cell lineage dynamics in tongue cancers are unclear. Here, using a mouse model of chemically (4-nitroquinoline-1-oxide: 4-NQO) induced tongue cancer and the multicolor lineage tracing method, we found that each unit of the tumor was generated by a single cell and that the assembly of such cells formed a polyclonal tumor. Although many Bmi1-positive cells within the tongue cancer specimens failed to proliferate, some proliferated continuously and supplied tumor cells to the surrounding area. This process eventually led to the formation of areas derived from single cells after 1-3 months, as determined using the multicolor lineage tracing method, indicating that such cells could serve as cancer stem cells. These results indicate that LESCs could serve as the origin for tongue cancer and that cancer stem cells are present in tongue tumors.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/srep39386DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5177893PMC
December 2016

Abnormal hematopoiesis and autoimmunity in human subjects with germline IKZF1 mutations.

J Allergy Clin Immunol 2017 Jul 6;140(1):223-231. Epub 2016 Dec 6.

Department of Pediatrics and Developmental Biology, Perinatal and Maternal Medicine, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan. Electronic address:

Background: Ikaros, which is encoded by IKZF1, is a transcriptional factor that play a critical role in hematopoiesis. Somatic IKZF1 alterations are known to be involved in the pathogenesis of leukemia in human subjects. Recently, immunodeficiency caused by germline IKZF1 mutation has been described.

Objective: We sought to describe the clinical and immunologic phenotypes of Japanese patients with heterozygous IKZF1 mutations.

Methods: We performed whole-exome sequencing in patients from a dysgammaglobulinemia or autoimmune disease cohort and used a candidate gene approach in 4 patients. Functional and laboratory studies, including detailed lymphopoiesis/hematopoiesis analysis in the bone marrow, were performed.

Results: Nine patients from 6 unrelated families were identified to have heterozygous germline mutations in IKZF1. Age of onset was 0 to 20 years (mean, 7.4 years). Eight of 9 patients presented with dysgammaglobulinemia accompanied by B-cell deficiency. Four of 9 patients had autoimmune disease, including immune thrombocytopenic purpura, IgA vasculitis, and systemic lupus erythematosus. Nonautoimmune pancytopenia was observed in 1 patient. All of the mutant Ikaros protein demonstrated impaired DNA binding to the target sequence and abnormal diffuse nuclear localization. Flow cytometric analysis of bone marrow revealed reduced levels of common lymphoid progenitors and normal development of pro-B to pre-B cells.

Conclusions: Germline heterozygous IKZF1 mutations cause dysgammaglobulinemia; hematologic abnormalities, including B-cell defect; and autoimmune diseases.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2016.09.029DOI Listing
July 2017

Diagnostic challenge of Diamond-Blackfan anemia in mothers and children by whole-exome sequencing.

Int J Hematol 2017 Apr 23;105(4):515-520. Epub 2016 Nov 23.

Department of Pediatrics, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-kogushi, Ube, Yamaguchi, 755-8505, Japan.

Diamond-Blackfan anemia (DBA) is a pure red cell aplasia that arises from defective ribosomal proteins (RPs). Patients with this rare ribosomopathy present with neonatal anemia and occasional dysmorphism. Clinical heterogeneity and clusters of causative RP genes hamper the diagnosis and perinatal management. We report three mother-and-child pairs of anemia who were finally diagnosed by whole-exome sequencing. Each pair showed distinct disease severity and response to anemia treatment. Only one mother had the diagnostic dysmorphism, including short stature, webbed neck, and thenar hypoplasia. This mother had a frame-shift mutation of RPL11 (exon 3, c.58_59del). Her infant showed transient neonatal anemia, but had no mutations of RP genes. The other mother-child pairs had a missense mutation of RPS19 (exon 4, c.185G>A), and a splicing error of RPS7 (exon 3, c.76-1G>T), respectively. Other than the reported mutations, there were no variants in genes significantly associated with anemia. Our results suggested that whole-exome sequencing (WES) is effective for achieving a prompt and correct diagnosis of human ribosomopathy.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s12185-016-2151-7DOI Listing
April 2017

Efficacy of Ifosfamide-Cisplatin-Etoposide (ICE) Chemotherapy for a CNS Germinoma in a Child With Down Syndrome.

J Pediatr Hematol Oncol 2017 01;39(1):e39-e42

Departments of *Pediatrics †Neurosurgery ‡Radiation Oncology and Image-Applied Therapy §Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan.

Intracranial germ cell tumor is sometimes associated with Down syndrome; however, no optimal treatment has been developed due to the high risk of recurrence and treatment-related mortality. Here, we report on a patient with an intracranial germinoma in the bilateral basal ganglia. The patient received 3 courses of ifosfamide-cisplatin-etoposide in combination with whole-brain irradiation (24 Gy), with no serious complications. The patient is alive and disease free 16 months after the initial diagnosis. This regimen is a feasible treatment for intracranial germ cell tumor associated with Down syndrome, although careful attention must be paid to the increased risk for severe infection.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/MPH.0000000000000711DOI Listing
January 2017

Haploinsufficiency of TNFAIP3 (A20) by germline mutation is involved in autoimmune lymphoproliferative syndrome.

J Allergy Clin Immunol 2017 Jun 12;139(6):1914-1922. Epub 2016 Nov 12.

Department of Pediatrics and Developmental Biology, Tokyo Medical and Dental University, Tokyo, Japan.

Background: Autoimmune diseases in children are rare and can be difficult to diagnose. Autoimmune lymphoproliferative syndrome (ALPS) is a well-characterized pediatric autoimmune disease caused by mutations in genes associated with the FAS-dependent apoptosis pathway. In addition, various genetic alterations are associated with the ALPS-like phenotype.

Objective: The aim of the present study was to elucidate the genetic cause of the ALPS-like phenotype.

Methods: Candidate genes associated with the ALPS-like phenotype were screened by using whole-exome sequencing. The functional effect of the identified mutations was examined by analyzing the activity of related signaling pathways.

Results: A de novo heterozygous frameshift mutation of TNF-α-induced protein 3 (TNFAIP3, A20), a negative regulator of the nuclear factor κB pathway, was identified in one of the patients exhibiting the ALPS-like phenotype. Increased activity of the nuclear factor κB pathway was associated with haploinsufficiency of TNFAIP3 (A20).

Conclusion: Haploinsufficiency of TNFAIP3 (A20) by a germline heterozygous mutation leads to the ALPS phenotype.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jaci.2016.09.038DOI Listing
June 2017