Papers - Narumi, Satoshi

Methylome analysis of thyroid ectopy shows no disease-specific DNA methylation signature.

Narumi S, 責任著者, Matsubara K, Ishii T, Hasegawa T

Clinical Pediatric Endocrinology 27 ( 4 ) 235 - 238 2018

Accepted,  ISSN  0918-5739

• Access to Document (DOI)

Identification of compound heterozygous TSHR mutations (R109Q and R450H) in a patient with nonclassic TSH resistance and functional characterization of the mutant receptors

Sugisawa Chiho, Abe Kiyomi, Sunaga Yuka, Taniyama Matsuo, Hasegawa Tomonobu, Narumi Satoshi, 任著者

Clinical Pediatric Endocrinology 27 ( 3 ) 123 - 130 2018

Accepted,  ISSN  0918-5739

　View Summary

Genetic defects of the TSH receptor (TSHR) signaling pathway cause a form of congenital hypothyroidism (CH) known as TSH resistance. Consistent with the physiological understanding that thyroidal iodine uptake is up-regulated by TSHR signaling, most patients with TSH resistance have low to normal thyroidal 123I uptake representing the classic TSH resistance. However, paradoxically high 123I uptake was reported in four molecularly-confirmed patients indicating nonclassic TSH resistance. Here, we report the fifth patient with the nonclassic phenotype. He was a 12-yr-old CH patient and treated with levothyroxine. At the age 11 yr, he showed slightly small thyroid gland and elevated thyroidal 123I uptake. Genetic analysis showed that he was compound heterozygous for two known missense mutations (Arg109Gln and Arg450His) in the TSHR gene. Further, the signal transduction of Arg109Gln-TSHR was defective in both Gs- and Gq-coupled pathways, while Arg450His-TSHR showed Gq-dominant defect. 123I uptake was evaluated earlier in 16 patients with TSH resistance, and a correlation between TSH levels and 123I uptake was shown in patients with specific genotypes (Arg450His or Leu653Val). Collectively, we have re-confirmed that the emergence of the nonclassic phenotype requires two factors: mutant TSHR with Gq-dominant coupling defect and relatively high levels of serum TSH.

• Access to Document (DOI)

Functional Characterization of a Novel KLF11 Mutation Identified in a Family with Autoantibody-Negative Type 1 Diabetes

Ushijima Kikumi, Kawamura Tomoyuki, Ogata Tsutomu, Yokota Lchiro, Sugihar Shigetaka, Narumi Satoshi, Fukami Maki

HORMONE RESEARCH IN PAEDIATRICS 90   84 - 85 2018

Accepted,  ISSN  1663-2818

Novel compound heterozygous mutations identified by whole exome sequencing in a Japanese patient with geroderma osteodysplastica

Ryojun Takeda, Masaki Takagi, Hiroyuki Shinohara, Hiroshi Futagawa, Satoshi Narumi, Tomonobu Hasegawa, Gen Nishimura, Hiroshi Yoshihashi

EUROPEAN JOURNAL OF MEDICAL GENETICS (ELSEVIER SCIENCE BV)  60 ( 12 ) 635 - 638 2017.12

Accepted,  ISSN  1769-7212

　View Summary

Geroderma osteodysplastica (GO) is a subtype of cutis laxa syndrome characterized by congenital wrinkly skin, a prematurely aged face, extremely short stature, and osteoporosis leading to recurrent fractures. GO exhibits an autosomal recessive inheritance pattern and is caused by loss-of-function mutations in GORAB, which encodes a protein important for Golgi-related transport. Using whole exome sequencing, we identified novel compound heterozygous nonsense mutations in the GORAB in a GO patient.
The patient was a 14-year-old Japanese boy. Wrinkled skin and joint laxity were present at birth. At 1 year of age, he was clinically diagnosed with cutis laxa syndrome based on recurrent long bone fractures and clinical features, including wrinkled skin, joint laxity, and a distinctive face. He did not show retarded gross motor and cognitive development. At 11 years of age, he was treated with oral bisphosphonate and vitamin D owing to recurrent multiple spontaneous fractures of the vertebral and extremity bones associated with a low bone mineral density (BMD). Bisphosphonate treatment improved his BMD and fracture rate. Whole exome sequencing revealed two novel compound heterozygous nonsense mutations in the GORAB gene (p. Arg60* and p. Gln124*), and the diagnosis of GO was established. GO is a rare connective tissue disorder. Approximately 60 cases have been described to date, and this is the first report of a patient from Japan. Few studies have reported the effects of bisphosphonate treatment in GO patients with recurrent spontaneous fractures. Based on this case study, we hypothesize that oral bisphosphonate and vitamin D are effective and safe treatment options for the management of recurrent fractures in GO patients. It is important to establish a precise diagnosis of GO to prevent recurrent fractures and optimize treatment plans. (C) 2017 Elsevier Masson SAS. All rights reserved.

• Access to Document (DOI)

PTEN胚細胞変異を同定した4歳発症の機能性甲状腺結節の1例

長崎 啓祐, 入月 浩美, 鳴海 覚志, 小飼 貴彦, 菱沼 昭

日本内分泌学会雑誌 ((一社)日本内分泌学会)  93 ( 4 ) 1126 - 1126 2017.12

ISSN  0029-0661

Mild thyroid peroxidase deficiency caused by TPO mutations with residual activity: Correlation between clinical phenotypes and enzymatic activity

Satoshi Narumi, Larry A. Fox, Keisuke Fukudome, Zenichi Sakaguchi, Chiho Sugisawa, Kiyomi Abe, Kaori Kameyama, Tomonobu Hasegawa

ENDOCRINE JOURNAL (JAPAN ENDOCRINE SOC)  64 ( 11 ) 1087 - 1097 2017.11

Accepted,  ISSN  0918-8959

　View Summary

Thyroid peroxidase (TPO) deficiency, caused by biallelic TPO mutations, is a well-established genetic form of congenital hypothyroidism (CH). More than 100 patients have been published, and the patients have been diagnosed mostly in the frame of newborn screening (NBS) programs. Correlation between clinical phenotypes and TPO activity remains unclear. Here, we report clinical and molecular findings of two unrelated TPO mutation-carrying mildly hypothyroid patients. The two patients were born at term after an uneventful pregnancy and delivery, and were NBS negative. They sought medical attention due to goiter at age 8 years. Evaluation of the thyroid showed mild elevation of serum TSH levels, normal or slightly low serum T-4 levels, high serum T-3 to T-4 molar ratio, high serum thyroglobulin levels, and high thyroidal I-123 uptake. We performed next-generation sequencing-based genetic screening, and found that one patient was compound heterozygous for two novel TPO mutations (p.Asp224del; c.820-2A>G), and the other was homozygous for a previously known mutation (p.Trp527Cys). In vitro functional analyses using HEK293 cells showed that the two amino acid-altering mutations (p.Asp224del and p.Trp527Cys) caused partial loss of the enzymatic activity. In conclusion, we report that TPO mutations with residual activity are associated with mild TPO deficiency, which is clinically characterized by marked goiter, mild TSH elevation, high serum T-3 to T-4 molar ratio, and high serum thyroglobulin levels. Our findings illuminate the hitherto under-recognized correlation between clinical phenotypes and residual enzymatic activity among patients with TPO deficiency.

• Access to Document (DOI)

Next generation sequencing-based mutation screening of 86 patients with idiopathic short stature.

Atsushi Hattori, Yuko Katoh-Fukui, Akie Nakamura, Keiko Matsubara, Tsutomu Kamimaki, Hiroyuki Tanaka, Sumito Dateki, Masanori Adachi, Koji Muroya, Shinobu Yoshida, Shinobu Ida, Marie Mitani, Keisuke Nagasaki, Tsutomu Ogata, Erina Suzuki, Kenichiro Hata, Kazuhiko Nakabayashi, Yoichi Matsubara, Satoshi Narumi, Toshiaki Tanaka, Maki Fukami

Endocrine journal 64 ( 10 ) 947 - 954 2017.10

Accepted,  ISSN  0918-8959

　View Summary

Although mutations in ACAN, FGFR3, NPR2, and SHOX typically lead to skeletal dysplasia, and mutations in GHRHR, GH1, GHR, STAT5B, IGF1, IGFALS, and IGF1R usually underlie hormonal defects of the growth hormone (GH)-insulin-like growth factor 1 (IGF1) axis, such mutations have also been identified in patients with idiopathic short stature (ISS). Of these, SHOX abnormalities are known to account for a certain percentage of ISS cases, whereas the frequency of mutations in the other 10 genes in ISS cohorts remains unknown. Here, we performed next-generation sequencing-based mutation screening of the 10 genes in 86 unrelated Japanese ISS patients without SHOX abnormalities. We searched for rare protein-altering variants. The functional significance of the identified variants was assessed by in silico analyses. Consequently, we identified 18 heterozygous rare variants in 19 patients, including four probable damaging variants in ACAN, six pathogenicity-unknown variants in FGFR3, GHRHR, GHR, and IGFALS, and eight possible benign variants. Pathogenic variants in NPR2, GH1, and IGF1 were absent from our cohort. Unlike previously reported patients with ACAN mutations, our four patients with ACAN variants manifested non-specific short stature with age-appropriate or mildly delayed bone ages, and had parents of normal stature. These results indicate that ACAN mutations can underlie ISS without characteristic skeletal features, and that such mutations are possibly associated with de novo occurrence or low penetrance. In addition, our data imply that mutations in FGFR3, NPR2, and GH-IGF1 axis genes play only limited roles in the etiology of ISS.

• Access to Document (DOI)

Paradoxical gain-of-function mutant of the G-protein-coupled receptor PROKR2 promotes early puberty

Maki Fukami, Erina Suzuki, Yoko Izumi, Tomohiro Torii, Satoshi Narumi, Maki Igarashi, Mami Miyado, Momori Katsumi, Yasuko Fujisawa, Kazuhiko Nakabayashi, Kenichiro Hata, Akihiro Umezawa, Yoichi Matsubara, Junji Yamauchi, Tsutomu Ogata

JOURNAL OF CELLULAR AND MOLECULAR MEDICINE (WILEY)  21 ( 10 ) 2623 - 2626 2017.10

Accepted,  ISSN  1582-4934

　View Summary

The human genome encodes -750 G-protein-coupled receptors (GPCRs), including prokineticin receptor 2 (PROKR2) involved in the regulation of sexual maturation. Previously reported pathogenic gain-of-function mutations of GPCR genes invariably encoded aberrant receptors with excessive signal transduction activity. Although in vitro assays demonstrated that an artificially created inactive mutant of PROKR2 exerted paradoxical gain-of-function effects when co-transfected with wild-type proteins, such a phenomenon has not been observed in vivo. Here, we report a heterozygous frameshift mutation of PROKR2 identified in a 3.5-year-old girl with central precocious puberty. The mutant mRNA escaped nonsense-mediated decay and generated a GPCR lacking two transmembrane domains and the carboxyl-terminal tail. The mutant protein had no in vitro signal transduction activity; however, cells co-expressing the mutant and wild-type PROKR2 exhibited markedly exaggerated ligand-induced Ca2+ responses. The results indicate that certain inactive PROKR2 mutants can cause early puberty by enhancing the functional property of coexisting wild-type proteins. Considering the structural similarity among GPCRs, this paradoxical gain-of-function mechanism may underlie various human disorders.

• Access to Document (DOI)

Paradoxical gain-of-function mutant of the G-protein-coupled receptor PROKR2 promotes early puberty.

Fukami M, Suzuki E, Izumi Y, Torii T, Narumi S, Igarashi M, Miyado M, Katsumi M, Fujisawa Y, Nakabayashi K, Hata K, Umezawa A, Matsubara Y, Yamauchi J, Ogata T

Journal of cellular and molecular medicine 21 ( 10 ) 2623 - 2626 2017.10

ISSN  1582-1838

• Access to Document (DOI)

Paradoxical gain-of-function mutant of the G-protein-coupled receptor PROKR2 promotes early puberty.

Maki Fukami, Erina Suzuki, Yoko Izumi, Tomohiro Torii, Satoshi Narumi, Maki Igarashi, Mami Miyado, Momori Katsumi, Yasuko Fujisawa, Kazuhiko Nakabayashi, Kenichiro Hata, Akihiro Umezawa, Yoichi Matsubara, Junji Yamauchi, Tsutomu Ogata

Journal of cellular and molecular medicine (Wiley-Blackwell)  21 ( 10 ) 2623 - 2626 2017.10

Accepted,  ISSN  1582-1838

　View Summary

The human genome encodes ~750 G-protein-coupled receptors (GPCRs), including prokineticin receptor 2 (PROKR2) involved in the regulation of sexual maturation. Previously reported pathogenic gain-of-function mutations of GPCR genes invariably encoded aberrant receptors with excessive signal transduction activity. Although in vitro assays demonstrated that an artificially created inactive mutant of PROKR2 exerted paradoxical gain-of-function effects when co-transfected with wild-type proteins, such a phenomenon has not been observed in vivo. Here, we report a heterozygous frameshift mutation of PROKR2 identified in a 3.5-year-old girl with central precocious puberty. The mutant mRNA escaped nonsense-mediated decay and generated a GPCR lacking two transmembrane domains and the carboxyl-terminal tail. The mutant protein had no in vitro signal transduction activity; however, cells co-expressing the mutant and wild-type PROKR2 exhibited markedly exaggerated ligand-induced Ca2+ responses. The results indicate that certain inactive PROKR2 mutants can cause early puberty by enhancing the functional property of coexisting wild-type proteins. Considering the structural similarity among GPCRs, this paradoxical gain-of-function mechanism may underlie various human disorders.

• Access to Document (DOI)

Homozygous DUOXA2 mutation (p.Tyr138*) in a girl with congenital hypothyroidism and her apparently unaffected brother: Case report and review of the literature

Chiho Sugisawa, Shinji Higuchi, Masaki Takagi, Yukihiro Hasegawa, Matsuo Taniyama, Kiyomi Abe, Tomonobu Hasegawa, Satoshi Narumi

ENDOCRINE JOURNAL (JAPAN ENDOCRINE SOC)  64 ( 8 ) 807 - 812 2017.08

Accepted,  ISSN  0918-8959

　View Summary

Mutations in DUOXA2, encoding dual oxidase maturation factor 2, is a rare genetic cause of congenital hypothyroidism. Only four biallelic DUOXA2 mutation carriers have been described to date. This study was conducted to report the clinical and genetic findings of a DUOXA2 mutation-carrying family, and to review the previously reported cases. The proband was a 4-year-old girl, who was diagnosed as having congenital hypothyroidism in the frame of newborn screening. She had a high serum TSH level (138 mU/L) and a low free T4 level (0.4 ng/dL). Ultrasonography revealed goiter. She was immediately treated with levothyroxine. At age 3 years, reevaluation of her thyroid function showed a slightly elevated serum TSH level (11.0 mU/L) with normal free T4 level. Screening of the eleven congenital hypothyroidism-related genes demonstrated a previously reported nonsense DUOXA2 mutation (p.Tyr138*) in the homozygous state. Unexpectedly, we also found that the elder brother of the proband, who had no significant past medical history, had the identical homozygous mutation. Using expression experiments with HEK293 cells, we confirmed that p. Tyr138* was a loss-of-function mutation. In the literature, clinical courses of three patients were described, showing characteristic age-dependent improvement of the thyroid function. In conclusion, The proband showed comparable clinical phenotype to previously reported cases, while her brother was unaffected. The phenotypic spectrum of DUOXA2 mutations could be broader than currently accepted.

• Access to Document (DOI)

SOX2 nonsense mutation in a patient clinically diagnosed with non-syndromic hypogonadotropic hypogonadism

Hirohito Shima, Akira Ishii, Yasunori Wada, Junya Kizawa, Tadashi Yokoi, Noriyuki Azuma, Yoichi Matsubara, Erina Suzuki, Akie Nakamura, Satoshi Narumi, Maki Fukami

ENDOCRINE JOURNAL (JAPAN ENDOCRINE SOC)  64 ( 8 ) 813 - 817 2017.08

Accepted,  ISSN  0918-8959

　View Summary

Hypogonadotropic hypogonadism (HH) is a genetically heterogeneous condition that occurs either as an isolated disorder or as a component of congenital malformation syndromes. SOX2 is a causative gene of syndromic HH characterized by anophthalmia, microphthalmia, or coloboma and other neurological defects such as epilepsy. To date, the causal relationship between SOX2 abnormalities and non-syndromic HH remains speculative. Here, we identified a nonsense mutation of SOX2 in a male patient clinically diagnosed with non-syndromic HH. The patient had epilepsy but no additional clinical features. Ophthalmological examination revealed no abnormalities except for decreased thickness of the retinal nerve fiber layer. Audiometry showed mild sensorineural hearing impairment of both ears. Hormonal evaluation suggested isolated gonadotropin deficiency. Next-generation sequencing-based mutation screening of 13 major causative genes for HH identified a p.Lys35* mutation in SOX2 and excluded pathogenic mutations in other tested genes. The p.Lys35* mutation appeared to encode a non-functioning SOX2 protein that lacks 283 of 317 amino acids. The SOX2 mutation was absent in the maternal DNA sample, while a paternal sample was unavailable for sequence analysis. These results expand the clinical consequences of SOX2 haploinsufficiency to include non-syndromic HH. Systematic mutation screening using a next-generation sequencer and detailed evaluation of nonspecific ocular/neurological features may help identify SOX2 mutation-positive individuals among HH patients.

• Access to Document (DOI)

Genetic defects in pediatric-onset adrenal insufficiency in Japan

Amano N, Narumi S, Hayashi M, Takagi M, Imai K, Nakamura T, Hachiya R, Sasaki G, Homma K, Ishii T, Hasegawa T

European Journal of Endocrinology 177 ( 2 ) 187 - 194 2017.08

Accepted,  ISSN  0804-4643

• Access to Document (DOI)

部分型TPO異常症 新生児マススクリーニングが陰性であったTPO変異の2例

鳴海 覚志, 阿部 清美, Fox Larry A., 福留 啓祐, 坂口 善市, 深見 真紀, 長谷川 奉延

日本内分泌学会雑誌 ((一社)日本内分泌学会)  93 ( 1 ) 261 - 261 2017.04

ISSN  0029-0661

A Novel De Novo Germline Mutation Glu40Lys in AKT3 Causes Megalencephaly with Growth Hormone Deficiency

Masaki Takagi, Kazushige Dobashi, Keiko Nagahara, Mitsuhiro Kato, Gen Nishimura, Ryuji Fukuzawa, Satoshi Narumi, Tomonobu Hasegawa

AMERICAN JOURNAL OF MEDICAL GENETICS PART A (WILEY)  173 ( 4 ) 1071 - 1076 2017.04

Accepted,  ISSN  1552-4825

　View Summary

Germline or somatic gain-of-function mutations in the v-akt murine thymoma viral oncogene homolog 3 (AKT3) have been reported to cause syndromic megalencephaly. We describe a novel germline mutation, p.Glu40Lys, in AKT3. Phenotypically, the patient presented with megalencephaly with hypotonia, apparent connective tissue laxity, and growth hormone (GH) deficiency. To our knowledge, this is the first instance of a patient with megalencephaly with GH deficiency, harboring a germline de novo mutation in AKT3. (C) 2017 Wiley Periodicals, Inc.

• Access to Document (DOI)

Luscan-Lumish症候群による巨人症の機序の解析

隅田 健太郎, 福岡 秀規, 井口 元三, 小武 由紀子, 吉田 健一, 松本 隆作, 坂東 弘教, 西澤 衡, 高橋 路子, 鳴海 覚志, 小川 渉, 長谷川 奉延, 高橋 裕

日本内分泌学会雑誌 ((一社)日本内分泌学会)  93 ( 1 ) 263 - 263 2017.04

ISSN  0029-0661

同胞間で異なる経過をたどる先天性甲状腺機能低下症 病型診断結果と遺伝子診断結果

小泉 美紀子, 川井 正信, 大沼 真輔, 中長 摩利子, 庄司 保子, 阿部 清美, 佐藤 武志, 鳴海 覚志, 長谷川 奉延, 惠谷 ゆり, 位田 忍

日本内分泌学会雑誌 ((一社)日本内分泌学会)  93 ( 1 ) 343 - 343 2017.04

ISSN  0029-0661

サイログロブリン遺伝子異常による先天性甲状腺機能低下症4例の臨床的比較検討

川北 葵, 山本 幸代, 久保 和泰, 江口 真美, 齋藤 玲子, 後藤 元秀, 川越 倫子, 河田 泰定, 鳴海 覚志, 長谷川 奉延, 楠原 浩一

日本内分泌学会雑誌 ((一社)日本内分泌学会)  93 ( 1 ) 261 - 261 2017.04

ISSN  0029-0661

新規遺伝子変異を同定したアンドロゲン不応症の1例

岩橋 めぐみ, 小澤 綾子, 佐藤 武志, 鳴海 覚志, 長谷川 奉延, 宮田 市郎

日本内分泌学会雑誌 ((一社)日本内分泌学会)  93 ( 1 ) 381 - 381 2017.04

ISSN  0029-0661

A novel heterozygous intronic mutation in POU1F1 is associated with combined pituitary hormone deficiency

Masaki Takagi, Hotaka Kamasaki, Hiroko Yagi, Ryuji Fukuzawa, Satoshi Narumi, Tomonobu Hasegawa

ENDOCRINE JOURNAL (JAPAN ENDOCRINE SOC)  64 ( 2 ) 229 - 234 2017.02

Accepted,  ISSN  0918-8959

　View Summary

POU class 1 homeobox 1 (POUlFi) regulates pituitary cell- specific gene expression of somatotropes, lactotropes, and thyrotropes. In humans, two POUlF1 isoforms (long and short isoform), which are generated by the alternative use of the splice acceptor site for exon 2, have been identified. To date, more than 30 POU1F1 mutations in patients with combined pituitary hormone deficiency (CPHD) have been described. All POU1F1 variants reported to date affect both the short and long isoforms of the POUlF I protein; therefore, it is unclear at present whether a decrease in the function of only one of these two isoforms is sufficient for disease onset in humans. Here, we described a sibling case of CPHD carrying a heterozygous mutation in intron 1 of POU1F1. In vitro experiments showed that this mutation resulted in exon 2- skipping of only in the short isoform of POU1F1, while the long isoform remained intact. This result strongly suggests the possibility, for the first time, that isolated mutations in the short isoform of POU1Fi could be sufficient for induction of POU1Fl- related CPHD. This finding improves our understanding of the molecular mechanisms, and developmental course associated with mutations in POU1F1.

• Access to Document (DOI)