1
|
Yuan M, Shan Y, Xu F, Yang L, Sun C, Cheng R, Wu B, Zhang Z, Cao Y, Zhang R, Zhou W, Cheng G, Hu L. A newborn with a pathogenic variant in ASXL2 expanding the phenotype of SHAPNS: a case report and literature review. Transl Pediatr 2023; 12:86-96. [PMID: 36798937 PMCID: PMC9926125 DOI: 10.21037/tp-22-220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 12/02/2022] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Shashi-Pena syndrome (SHAPNS) is a developmental disorder caused by mutations in additional sex combs-like Protein 2 (ASXL2). Since 2016, only 12 cases from 10 families have been reported. However, neonatal period characteristics remain largely unknown. Herein, we report a case with a pathogenic variant in ASXL2 in a newborn. CASE DESCRIPTION A newborn was diagnosed with a previously unreported de novo truncating mutation in ASXL2 (NM_018263.6) at 21 days and the clinical characteristics of all probands with ASXL2-related SHAPNS was reported in the literature. He had persistent hypoglycemia caused by inappropriate insulin levels and achieved stable glucose levels after octreotide treatment. Magnetic resonance imaging (MRI) revealed a small cerebellum, and fundoscopy showed bilateral retinal paving-stone-like white lesions. The results of trio-based whole exome sequencing (WES) were returned on the 21st day of life, and a heterozygous de novo truncating pathogenic c.1792C>T (p.Gln598*) variant in exon 11 of the ASXL2 gene was identified. The clinical features of our patient and another 10 probands with ASXL2-related SHAPNS reported in the literature were included in this review. More than half shared recognizable clinical features, including hypertelorism (11/11), broad nasal tip (10/11), arched eyebrows (9/11), a large V-shaped glabellar nevus flammeus on the forehead (9/11), low-set ears (8/11), posteriorly rotated ears (7/11), proptosis (6/11) and deep palm creases (6/11). Major clinical issues included feeding difficulties (10/11), developmental delay (10/11), skeletal and/or extremity abnormalities (8/11), progressive macrocephaly (8/11), hypotonia (8/11), hypoglycemia (6/11) and seizures (6/11). Neurodevelopmental regression was possible in patients (2/11) with normal MRI findings who later developed nonfebrile seizures. CONCLUSIONS We present a newborn diagnosing the SHAPNS by trio-WES, which is the earliest age of diagnosis. The application of octreotide for hypoglycemia, the small cerebellum and bilateral paving-stone-like white lesions of the retinas are described for the first time in an individual with ASXL2-related SHAPNS. Additional clinical reports of neonates with damaging ASXL2 variants are necessary to verify the mechanism and optimal treatment of ASXL2-related hypoglycemia, neurological damage and optic impairment. Neurological, endocrinological, ophthalmological, and rehabilitative follow-ups of these patients are necessary and important.
Collapse
Affiliation(s)
- Meng Yuan
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Yuanyuan Shan
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Fanshu Xu
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Lin Yang
- Department of Endocrinology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.,Clinical Genetic Center, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.,Shanghai Key Laboratory of Birth Defects, The Translational Medicine Center of Children Development and Disease of Fudan University, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Chengjun Sun
- Department of Endocrinology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Ruoqian Cheng
- Department of Endocrinology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Bingbing Wu
- Shanghai Key Laboratory of Birth Defects, The Translational Medicine Center of Children Development and Disease of Fudan University, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Zhehuan Zhang
- Department of Ophthalmology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Yun Cao
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.,Key Laboratory of Neonatal Diseases, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Rong Zhang
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Wenhao Zhou
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.,Clinical Genetic Center, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.,Shanghai Key Laboratory of Birth Defects, The Translational Medicine Center of Children Development and Disease of Fudan University, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China.,Key Laboratory of Neonatal Diseases, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Guoqiang Cheng
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| | - Liyuan Hu
- Department of Neonatology, Children's Hospital of Fudan University, National Children's Medical Center, Shanghai, China
| |
Collapse
|
2
|
Li M, Xu L, Zhang R, Dong C. Epigenetic Regulator ASXL2: Structure, Function and its Predictive Value in Diseases. Curr Protein Pept Sci 2023; 24:22-30. [PMID: 36503466 DOI: 10.2174/1389203724666221208103516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 10/22/2022] [Accepted: 10/22/2022] [Indexed: 12/14/2022]
Abstract
ASXL2, as a transcription regulator, is a research hotspot for tumor detection. The aberrant expression of ASXL2 protein has been mainly implicated in malignant hematological and heart diseases. To further explore the predictive value of ASXL2 in diseases, we reviewed the structure and function of ASXL2 protein, the post-translational modification mechanism, and the expression of ASXL2 protein in the pathogenesis of different diseases to provide a theoretical basis and support for the development of future treatments.
Collapse
Affiliation(s)
- Mengru Li
- College of Marine and Environmental Sciences, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Lijun Xu
- College of Marine and Environmental Sciences, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Rui Zhang
- College of Marine and Environmental Sciences, Tianjin University of Science and Technology, Tianjin 300457, China
| | - Chunming Dong
- College of Marine and Environmental Sciences, Tianjin University of Science and Technology, Tianjin 300457, China
| |
Collapse
|
3
|
Wang G, Yang L, Gao J, Mu H, Song Y, Jiang X, Chen B, Cui R. Identification of Candidate Biomarker ASXL2 and Its Predictive Value in Pancreatic Carcinoma. Front Oncol 2021; 11:736694. [PMID: 34692512 PMCID: PMC8531590 DOI: 10.3389/fonc.2021.736694] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/20/2021] [Indexed: 12/15/2022] Open
Abstract
Pancreatic adenocarcinoma is one of the most lethal diseases with a 5-year survival rate of about 8%. ASXL2 is an epigenetic regulator associated with various tumors including colorectal cancer, breast cancer, and myeloid leukemia. However, the role of ASXL2 in pancreatic cancer remains unclear. This is the first research focusing on the prognostic value of ASXL2 in pancreatic cancer. In this research, we aimed to explore the correlation between ASXL2 and the prognosis, as well as other features in PAAD. We obtained gene expression profiles of PAAD and normal tissues from TCGA, GEO, and Xena databases. TIMER and CIBERSORT algorithms were employed to investigate the effect of ASXL2 on tumor microenvironment. GSEA along with GO and KEGG enrichment analyses were conducted to uncover the biological functions of ASXL2. The response to various chemotherapeutic drugs was estimated by algorithms in R package “pRRophetic”, while the sensitivity to immunotherapy was quantified by TIDE score. We found that ASXL2 was upregulated in the PAAD samples and elevated expression of ASXL2 was linked to poor overall survival. ASXL2 DNA methylation contributed to ASXL2 expression. Functional annotation indicated that ASXL2 was mainly involved in inflammatory response and epithelial mesenchymal transition. Patients with high ASXL2 expression were more likely to benefit from immune checkpoint blockade, gemcitabine, and mitomycin-C. Finally, external datasets and biospecimens were used and the results further validated the aberrant expression of ASXL2 in PAAD samples. In summary, our results highlight that ASXL2 is a potential prognostic and predictive biomarker in pancreatic cancer.
Collapse
Affiliation(s)
- Gaoming Wang
- Department of Hepatopancreatobiliary Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Ludi Yang
- Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Jinli Gao
- Department of Pathology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Huiling Mu
- Department of Pathology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Yanxiang Song
- Department of Pathology, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Xiaohua Jiang
- Department of Hepatopancreatobiliary Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Bo Chen
- Department of Hepatopancreatobiliary Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| | - Ran Cui
- Department of Hepatopancreatobiliary Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, China
| |
Collapse
|
4
|
Cuddapah VA, Dubbs HA, Adang L, Kugler SL, McCormick EM, Zolkipli-Cunningham Z, Ortiz-González XR, McCormack S, Zackai E, Licht DJ, Falk MJ, Marsh ED. Understanding the phenotypic spectrum of ASXL-related disease: Ten cases and a review of the literature. Am J Med Genet A 2021; 185:1700-1711. [PMID: 33751773 DOI: 10.1002/ajmg.a.62156] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 02/10/2021] [Accepted: 02/22/2021] [Indexed: 01/11/2023]
Abstract
Over the past decade, pathogenic variants in all members of the ASXL family of genes, ASXL1, ASXL2, and ASXL3, have been found to lead to clinically distinct but overlapping syndromes. Bohring-Opitz syndrome (BOPS) was first described as a clinical syndrome and later found to be associated with pathogenic variants in ASXL1. This syndrome is characterized by developmental delay, microcephaly, characteristic facies, hypotonia, and feeding difficulties. Subsequently, pathogenic variants in ASXL2 were found to lead to Shashi-Pena syndrome (SHAPNS) and in ASXL3 to lead to Bainbridge-Ropers syndrome (BRPS). While SHAPNS and BRPS share many core features with BOPS, there also seem to be emerging clear differences. Here, we present five cases of BOPS, one case of SHAPNS, and four cases of BRPS. By adding our cohort to the limited number of previously published patients, we review the overlapping features of ASXL-related diseases that bind them together, while focusing on the characteristics that make each neurodevelopmental syndrome unique. This will assist in diagnosis of these overlapping conditions and allow clinicians to more comprehensively counsel affected families.
Collapse
Affiliation(s)
- Vishnu Anand Cuddapah
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Holly A Dubbs
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Departments of Neurology and Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,The Epilepsy Neurogenetics Initiative, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Laura Adang
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Steven L Kugler
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Elizabeth M McCormick
- Mitochondrial Medicine Frontier Program, Division of Human Genetics, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Zarazuela Zolkipli-Cunningham
- Mitochondrial Medicine Frontier Program, Division of Human Genetics, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Departments of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Xilma R Ortiz-González
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Departments of Neurology and Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,The Epilepsy Neurogenetics Initiative, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Shana McCormack
- Division of Endocrinology and Diabetes, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Elaine Zackai
- Departments of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,Division of Human Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Daniel J Licht
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| | - Marni J Falk
- Mitochondrial Medicine Frontier Program, Division of Human Genetics, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Departments of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - Eric D Marsh
- Division of Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.,Departments of Neurology and Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, USA.,The Epilepsy Neurogenetics Initiative, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
| |
Collapse
|
5
|
Cui R, Yang L, Wang Y, Zhong M, Yu M, Chen B. Elevated Expression of ASXL2 is Associated with Poor Prognosis in Colorectal Cancer by Enhancing Tumorigenesis and Inducing Cell Proliferation. Cancer Manag Res 2020; 12:10221-10228. [PMID: 33116876 PMCID: PMC7585280 DOI: 10.2147/cmar.s266083] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 09/21/2020] [Indexed: 12/24/2022] Open
Abstract
Objective Colorectal cancer is one of the most common malignant tumors worldwide. ASXL2 is an enhancer of the trithorax and polycomb genes, which have been proven to act in many tumor types. The role of ASXL2 in the occurrence and development of tumors has been extensively studied in recent years. However, the relationship between ASXL2 and the prognosis of CRC is still unclear. Materials and Methods In this study, quantitative real-time polymerase chain reaction (qRT-PCR), Western blot analysis and immunohistochemistry (IHC) were used to examine the expression of ASXL2 in CRC tissues. Cells were transfected with siRNAs or lentivirus to regulate the expression of ASXL2. The effects of ASXL2 on the proliferation of CRC cells were determined by CCK8 assay. Results This study demonstrated that ASXL2 was significantly more highly expressed in CRC specimens than in normal adjacent tissues. The upregulation of ASXL2 was related to advanced clinical stage. Patients who exhibited high expression levels of ASXL2 had poorer overall survival, whereas those with low expression of ASXL2 survived longer. Multivariate Cox regression analysis revealed that ASXL2 expression could be considered an independent prognostic factor for CRC. Inhibition or overexpression of ASXL2 markedly influenced the proliferation of CRC cells. Conclusion These results showed that ASXL2 could induce cell proliferation, which was associated with poor prognosis of CRC patients, suggesting that ASXL2 might be a new therapeutic target for CRC.
Collapse
Affiliation(s)
- Ran Cui
- Department of Hepatopancreatobiliary Surgery, East Hospital Affiliated Tongji University, Tongji University School of Medicine, Shanghai 200120, People's Republic of China
| | - Ludi Yang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Yiwei Wang
- State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Shanghai Jiao Tong University, Shanghai 200240, People's Republic of China
| | - Ming Zhong
- Department of Gastrointestinal Surgery, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China
| | - Minhao Yu
- Department of Gastrointestinal Surgery, Ren Ji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200127, People's Republic of China
| | - Bo Chen
- Department of Hepatopancreatobiliary Surgery, East Hospital Affiliated Tongji University, Tongji University School of Medicine, Shanghai 200120, People's Republic of China
| |
Collapse
|
6
|
Dinan AM, Atkins JF, Firth AE. ASXL gain-of-function truncation mutants: defective and dysregulated forms of a natural ribosomal frameshifting product? Biol Direct 2017; 12:24. [PMID: 29037253 PMCID: PMC5644247 DOI: 10.1186/s13062-017-0195-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 10/04/2017] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Programmed ribosomal frameshifting (PRF) is a gene expression mechanism which enables the translation of two N-terminally coincident, C-terminally distinct protein products from a single mRNA. Many viruses utilize PRF to control or regulate gene expression, but very few phylogenetically conserved examples are known in vertebrate genes. Additional sex combs-like (ASXL) genes 1 and 2 encode important epigenetic and transcriptional regulatory proteins that control the expression of homeotic genes during key developmental stages. Here we describe an ~150-codon overlapping ORF (termed TF) in ASXL1 and ASXL2 that, with few exceptions, is conserved throughout vertebrates. RESULTS Conservation of the TF ORF, strong suppression of synonymous site variation in the overlap region, and the completely conserved presence of an EH[N/S]Y motif (a known binding site for Host Cell Factor-1, HCF-1, an epigenetic regulatory factor), all indicate that TF is a protein-coding sequence. A highly conserved UCC_UUU_CGU sequence (identical to the known site of +1 ribosomal frameshifting for influenza virus PA-X expression) occurs at the 5' end of the region of enhanced synonymous site conservation in ASXL1. Similarly, a highly conserved RG_GUC_UCU sequence (identical to a known site of -2 ribosomal frameshifting for arterivirus nsp2TF expression) occurs at the 5' end of the region of enhanced synonymous site conservation in ASXL2. CONCLUSIONS Due to a lack of appropriate splice forms, or initiation sites, the most plausible mechanism for translation of the ASXL1 and 2 TF regions is ribosomal frameshifting, resulting in a transframe fusion of the N-terminal half of ASXL1 or 2 to the TF product, termed ASXL-TF. Truncation or frameshift mutants of ASXL are linked to myeloid malignancies and genetic diseases, such as Bohring-Opitz syndrome, likely at least in part as a result of gain-of-function or dominant-negative effects. Our hypothesis now indicates that these disease-associated mutant forms represent overexpressed defective versions of ASXL-TF. REVIEWERS This article was reviewed by Laurence Hurst and Eugene Koonin.
Collapse
Affiliation(s)
- Adam M Dinan
- Department of Pathology, Division of Virology, University of Cambridge, Cambridge, CB2 1QP, UK
| | - John F Atkins
- School of Biochemistry and Cell Biology, University College Cork, T12 YT57, Cork, Ireland.,Department of Human Genetics, University of Utah, Salt Lake City, UT, 84112, USA
| | - Andrew E Firth
- Department of Pathology, Division of Virology, University of Cambridge, Cambridge, CB2 1QP, UK.
| |
Collapse
|
7
|
Shashi V, Pena LD, Kim K, Burton B, Hempel M, Schoch K, Walkiewicz M, McLaughlin HM, Cho M, Stong N, Hickey SE, Shuss CM, Freemark MS, Bellet JS, Keels MA, Bonner MJ, El-Dairi M, Butler M, Kranz PG, Stumpel CT, Klinkenberg S, Oberndorff K, Alawi M, Santer R, Petrovski S, Kuismin O, Korpi-Heikkilä S, Pietilainen O, Aarno P, Kurki MI, Hoischen A, Need AC, Goldstein DB, Kortüm F, Bacino A, Lee BH, Balasubramanyam A, Burrage LC, Clark GD, Craigen WJ, Dhar SU, Emrick LT, Graham BH, Jain M, Lalani SR, Lewis RA, Moretti PM, Nicholas SK, Orange JS, Posey JE, Potocki L, Rosenfeld JA, Scott DA, Hanchard NA, Alyssa TA, Mercedes AE, Mashid AS, Bellen HJ, Yamamoto S, Wangler MF, Westerfield M, Postlethwait JH, Eng CM, Yang Y, Muzny DM, Ward PA, Ramoni RB, McCray AT, Kohane IS, Holm IA, Might M, Mazur P, Splinter K, Esteves C, Shashi V, Jiang YH, Pena LD, McConkie-Rosell A, Schoch K, Spillmann RC, Sullivan JA, Walley NM, Goldstein DB, Stong N, Beggs AH, Loscalzo J, MacRae CA, Silverman EK, Stoler JM, Sweetser DA, Maas RL, Krier JB, Rodan LH, Walsh CA, Cooper CM, Pallais JC, Donnell-Fink LA, Krieg EL, Lincoln SA, Briere LC, Jacob HJ, Worthey EA, Lazar J, Strong KA, Handley LH, Newberry JS, Bick DP, Schroeder MC, Brown DM, Birch CL, Levy SE, Boone BE, Dorset DC, Jones AL, Manolio TA, Mulvihill JJ, Wise AL, Dayal JG, Eckstein DJ, Krasnewich DM, Loomis CR, Mamounas LA, Iglesias B, Martin C, Koeller DM, Metz TO, Ashley EA, Fisher PG, Bernstein JA, Wheeler MT, Zornio PA, Waggott DM, Dries AM, Kohler JN, Dipple KM, Nelson SF, Palmer CG, Vilain E, Allard P, Dell Angelica EC, Lee H, Sinsheimer JS, Papp JC, Dorrani N, Herzog MR, Barseghyan H, Adams DR, Adams CJ, Burke EA, Chao KR, Davids M, Draper DD, Estwick T, Frisby TS, Frost K, Gahl WA, Gartner V, Godfrey RA, Goheen M, Golas GA, Gordon MG, Groden CA, Gropman AL, Hackbarth ME, Hardee I, Johnston JM, Koehler AE, Latham L, Latour YL, Lau CYC, Lee PR, Levy DJ, Liebendorder AP, Macnamara EF, Maduro VV, Malicdan MV, Markello TC, McCarty AJ, Murphy JL, Nehrebecky ME, Novacic D, Pusey BN, Sadozai S, Schaffer KE, Sharma P, Soldatos AG, Thomas SP, Tifft CJ, Tolman NJ, Toro C, Valivullah ZM, Wahl CE, Warburton M, Weech AA, Wolfe LA, Yu G, Hamid R, Newman JH, Phillips JA, Cogan JD. De Novo Truncating Variants in ASXL2 Are Associated with a Unique and Recognizable Clinical Phenotype. Am J Hum Genet 2016; 99:991-999. [PMID: 27693232 PMCID: PMC5065681 DOI: 10.1016/j.ajhg.2016.08.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 08/24/2016] [Indexed: 12/14/2022] Open
Abstract
The ASXL genes (ASXL1, ASXL2, and ASXL3) participate in body patterning during embryogenesis and encode proteins involved in epigenetic regulation and assembly of transcription factors to specific genomic loci. Germline de novo truncating variants in ASXL1 and ASXL3 have been respectively implicated in causing Bohring-Opitz and Bainbridge-Ropers syndromes, which result in overlapping features of severe intellectual disability and dysmorphic features. ASXL2 has not yet been associated with a human Mendelian disorder. In this study, we performed whole-exome sequencing in six unrelated probands with developmental delay, macrocephaly, and dysmorphic features. All six had de novo truncating variants in ASXL2. A careful review enabled the recognition of a specific phenotype consisting of macrocephaly, prominent eyes, arched eyebrows, hypertelorism, a glabellar nevus flammeus, neonatal feeding difficulties, hypotonia, and developmental disabilities. Although overlapping features with Bohring-Opitz and Bainbridge-Ropers syndromes exist, features that distinguish the ASXL2-associated condition from ASXL1- and ASXL3-related disorders are macrocephaly, absence of growth retardation, and more variability in the degree of intellectual disabilities. We were also able to demonstrate with mRNA studies that these variants are likely to exert a dominant-negative effect, given that both alleles are expressed in blood and the mutated ASXL2 transcripts escape nonsense-mediated decay. In conclusion, de novo truncating variants in ASXL2 underlie a neurodevelopmental syndrome with a clinically recognizable phenotype. This report expands the germline disorders that are linked to the ASXL genes.
Collapse
|
8
|
Shiba N, Yoshida K, Shiraishi Y, Okuno Y, Yamato G, Hara Y, Nagata Y, Chiba K, Tanaka H, Terui K, Kato M, Park MJ, Ohki K, Shimada A, Takita J, Tomizawa D, Kudo K, Arakawa H, Adachi S, Taga T, Tawa A, Ito E, Horibe K, Sanada M, Miyano S, Ogawa S, Hayashi Y. Whole-exome sequencing reveals the spectrum of gene mutations and the clonal evolution patterns in paediatric acute myeloid leukaemia. Br J Haematol 2016; 175:476-489. [PMID: 27470916 DOI: 10.1111/bjh.14247] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2016] [Accepted: 05/30/2016] [Indexed: 01/31/2023]
Abstract
Acute myeloid leukaemia (AML) is a molecularly and clinically heterogeneous disease. Targeted sequencing efforts have identified several mutations with diagnostic and prognostic values in KIT, NPM1, CEBPA and FLT3 in both adult and paediatric AML. In addition, massively parallel sequencing enabled the discovery of recurrent mutations (i.e. IDH1/2 and DNMT3A) in adult AML. In this study, whole-exome sequencing (WES) of 22 paediatric AML patients revealed mutations in components of the cohesin complex (RAD21 and SMC3), BCORL1 and ASXL2 in addition to previously known gene mutations. We also revealed intratumoural heterogeneities in many patients, implicating multiple clonal evolution events in the development of AML. Furthermore, targeted deep sequencing in 182 paediatric AML patients identified three major categories of recurrently mutated genes: cohesion complex genes [STAG2, RAD21 and SMC3 in 17 patients (8·3%)], epigenetic regulators [ASXL1/ASXL2 in 17 patients (8·3%), BCOR/BCORL1 in 7 patients (3·4%)] and signalling molecules. We also performed WES in four patients with relapsed AML. Relapsed AML evolved from one of the subclones at the initial phase and was accompanied by many additional mutations, including common driver mutations that were absent or existed only with lower allele frequency in the diagnostic samples, indicating a multistep process causing leukaemia recurrence.
Collapse
Affiliation(s)
- Norio Shiba
- Department of Haematology/Oncology, Gunma Children's Medical Centre, Shibukawa, Japan.,Department of Paediatrics, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Kenichi Yoshida
- Department of Pathology and Tumour Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yuichi Shiraishi
- Laboratory of DNA Information Analysis, Human Genome Centre, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Yusuke Okuno
- Department of Paediatrics, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Genki Yamato
- Department of Haematology/Oncology, Gunma Children's Medical Centre, Shibukawa, Japan.,Department of Paediatrics, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Yusuke Hara
- Department of Haematology/Oncology, Gunma Children's Medical Centre, Shibukawa, Japan.,Department of Paediatrics, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Yasunobu Nagata
- Department of Pathology and Tumour Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Kenichi Chiba
- Laboratory of DNA Information Analysis, Human Genome Centre, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Hiroko Tanaka
- Laboratory of Sequence Analysis, Human Genome Centre, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Kiminori Terui
- Department of Paediatrics, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Motohiro Kato
- Department of Paediatrics Haematology and Oncology Research, National Centre for Child Health and Development, Tokyo, Japan
| | - Myoung-Ja Park
- Department of Haematology/Oncology, Gunma Children's Medical Centre, Shibukawa, Japan
| | - Kentaro Ohki
- Department of Paediatrics Haematology and Oncology Research, National Centre for Child Health and Development, Tokyo, Japan
| | - Akira Shimada
- Department of Paediatrics, Okayama University Graduate School of Medicine, Okayama, Japan
| | - Junko Takita
- Department of Paediatrics, The University of Tokyo, Tokyo, Japan
| | - Daisuke Tomizawa
- Division of Leukaemia and Lymphoma, Children's Cancer Centre, National Centre for Child Health and Development, Tokyo, Japan
| | - Kazuko Kudo
- Department of Paediatrics, Fujita Health University School of Medicine, Toyoake, Japan
| | - Hirokazu Arakawa
- Department of Paediatrics, Gunma University Graduate School of Medicine, Maebashi, Japan
| | - Souichi Adachi
- Human Health Sciences, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takashi Taga
- Department of Paediatrics, Shiga University of Medical Science, Ohtsu, Japan
| | - Akio Tawa
- Department of Paediatrics, National Hospital Organization Osaka National Hospital, Osaka, Japan
| | - Etsuro Ito
- Department of Paediatrics, Hirosaki University Graduate School of Medicine, Hirosaki, Japan
| | - Keizo Horibe
- Clinical Research Centre, National Hospital Organization Nagoya Medical Centre, Nagoya, Japan
| | - Masashi Sanada
- Clinical Research Centre, National Hospital Organization Nagoya Medical Centre, Nagoya, Japan
| | - Satoru Miyano
- Laboratory of DNA Information Analysis, Human Genome Centre, Institute of Medical Science, The University of Tokyo, Tokyo, Japan.,Laboratory of Sequence Analysis, Human Genome Centre, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Seishi Ogawa
- Department of Pathology and Tumour Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yasuhide Hayashi
- Department of Haematology/Oncology, Gunma Children's Medical Centre, Shibukawa, Japan. .,Japanese Red Cross Gunma Blood Centre, Maebashi, Japan.
| |
Collapse
|
9
|
Khan FF, Li Y, Balyan A, Wang QT. WTIP interacts with ASXL2 and blocks ASXL2-mediated activation of retinoic acid signaling. Biochem Biophys Res Commun 2014; 451:101-6. [PMID: 25065743 DOI: 10.1016/j.bbrc.2014.07.080] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 07/16/2014] [Indexed: 10/25/2022]
Abstract
The Asx-like (ASXL) family proteins are chromatin factors that play dual roles in transcriptional activation and repression. ASXL2 is highly expressed in the heart and is required for proper heart development and function. Here, we identify a novel ASXL2-binding partner, the LIM domain-containing protein WTIP. Genetic and biochemical assays show a direct interaction between ASXL2 and WTIP. In HeLa cells, ASXL2 enhances retinoic acid-dependent luciferase activity, while WTIP represses it. Furthermore, WTIP blocks ASXL2's stimulatory effect on transcription. In addition, we found that ASXL2 and WTIP are expressed in mouse embryonic epicardial cells, a tissue that is regulated by retinoic acid signaling. Together, these results implicate ASXL2 and WTIP in regulation of retinoic acid signaling during heart development.
Collapse
Affiliation(s)
- Farida F Khan
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Yanyang Li
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Arjun Balyan
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA
| | - Q Tian Wang
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Ave., Chicago, IL 60607, USA.
| |
Collapse
|
10
|
Park UH, Seong MR, Kim EJ, Hur W, Kim SW, Yoon SK, Um SJ. Reciprocal regulation of LXRα activity by ASXL1 and ASXL2 in lipogenesis. Biochem Biophys Res Commun 2013; 443:489-94. [PMID: 24321552 DOI: 10.1016/j.bbrc.2013.11.124] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2013] [Accepted: 11/27/2013] [Indexed: 11/29/2022]
Abstract
Liver X receptor alpha (LXRα), a member of the nuclear receptor superfamily, plays a pivotal role in hepatic cholesterol and lipid metabolism, regulating the expression of genes associated with hepatic lipogenesis. The additional sex comb-like (ASXL) family was postulated to regulate chromatin function. Here, we investigate the roles of ASXL1 and ASXL2 in regulating LXRα activity. We found that ASXL1 suppressed ligand-induced LXRα transcriptional activity, whereas ASXL2 increased LXRα activity through direct interaction in the presence of the ligand. Chromatin immunoprecipitation (ChIP) assays showed ligand-dependent recruitment of ASXLs to ABCA1 promoters, like LXRα. Knockdown studies indicated that ASXL1 inhibits, while ASXL2 increases, lipid accumulation in H4IIE cells, similar to their roles in transcriptional regulation. We also found that ASXL1 expression increases under fasting conditions, and decreases in insulin-treated H4IIE cells and the livers of high-fat diet-fed mice. Overall, these results support the reciprocal role of the ASXL family in lipid homeostasis through the opposite regulation of LXRα.
Collapse
Affiliation(s)
- Ui-Hyun Park
- Department of Bioscience & Biotechnology, Institute of Bioscience, BK21 Graduate Program, Sejong University, Seoul 143-747, South Korea
| | - Mi-ran Seong
- Department of Bioscience & Biotechnology, Institute of Bioscience, BK21 Graduate Program, Sejong University, Seoul 143-747, South Korea
| | - Eun-Joo Kim
- Department of Molecular Biology, BK21 Graduate Program, Dankook University, Gyeonggi-do 448-701, South Korea
| | - Wonhee Hur
- Department of Molecular Biology, BK21 Graduate Program, Dankook University, Gyeonggi-do 448-701, South Korea
| | - Sung Woo Kim
- Department of Molecular Biology, BK21 Graduate Program, Dankook University, Gyeonggi-do 448-701, South Korea
| | - Seung Kew Yoon
- The Catholic University Liver Research Center & WHO Collaborating Center of Viral Hepatitis, The Catholic University, College of Medicine, Seoul 137-701, South Korea
| | - Soo-Jong Um
- Department of Bioscience & Biotechnology, Institute of Bioscience, BK21 Graduate Program, Sejong University, Seoul 143-747, South Korea.
| |
Collapse
|