1
|
Yamaguchi M, Sera Y, Toga-Yamaguchi H, Kanegane H, Iguchi Y, Fujimura K. Knockdown of the Shwachman-Diamond syndrome gene, SBDS, induces galectin-1 expression and impairs cell growth. Int J Hematol 2024; 119:383-391. [PMID: 38240987 DOI: 10.1007/s12185-024-03709-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 12/18/2023] [Accepted: 01/05/2024] [Indexed: 03/24/2024]
Abstract
Shwachman-Diamond syndrome (SDS) is an autosomal recessive disorder characterized by exocrine pancreatic insufficiency and bone marrow failure. The depletion of SBDS protein by RNA interference has been shown to cause inhibition of cell proliferation in several cell lines. However, the precise mechanism by which the loss of SBDS leads to inhibition of cell growth remains unknown. To evaluate the impaired growth of SBDS-knockdown cells, we analyzed Epstein-Barr virus-transformed lymphoblast cells (LCLs) derived from two patients with SDS (c. 183_184TA > CT and c. 258 + 2 T > C). After 3 days of culture, the growth of LCL-SDS cell lines was considerably less than that of control donor cells. By annealing control primer-based GeneFishing PCR screening, we found that galectin-1 (Gal-1) mRNA expression was elevated in LCL-SDS cells. Western blot analysis showed that the level of Gal-1 protein expression was also increased in LCL-SDS cells as well as in SBDS-knockdown 32Dcl3 murine myeloid cells. We confirmed that recombinant Gal-1 inhibited the proliferation of both LCL-control and LCL-SDS cells and induced apoptosis (as determined by annexin V-positive staining). These results suggest that the overexpression of Gal-1 contributes to abnormal cell growth in SBDS-deficient cells.
Collapse
Affiliation(s)
- Masafumi Yamaguchi
- Laboratory of Physiological Chemistry, Hiroshima International University, 5-1-1 Hirokoshingai, Kure-Shi, Hiroshima, 737-0112, Japan.
| | - Yukihiro Sera
- Laboratory of Physiological Chemistry, Hiroshima International University, 5-1-1 Hirokoshingai, Kure-Shi, Hiroshima, 737-0112, Japan
| | - Hanae Toga-Yamaguchi
- Laboratory of Physiological Chemistry, Hiroshima International University, 5-1-1 Hirokoshingai, Kure-Shi, Hiroshima, 737-0112, Japan
| | - Hirokazu Kanegane
- Department of Child Health and Development, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, BUnkyo-ku, Tokyo, 113-8519, Japan
| | - Yusuke Iguchi
- Laboratory of Physiological Chemistry, Hiroshima International University, 5-1-1 Hirokoshingai, Kure-Shi, Hiroshima, 737-0112, Japan
| | - Kingo Fujimura
- Department of Nursing, Yasuda Women's University, 6-13-1 Yasuhigashi, Asaminami-ku, Hiroshima, 731-0153, Japan
| |
Collapse
|
2
|
Oyarbide U, Shah AN, Staton M, Snyderman M, Sapra A, Calo E, Corey SJ. SBDS R126T rescues survival of sbds -/- zebrafish in a dose-dependent manner independently of Tp53. Life Sci Alliance 2023; 6:e202201856. [PMID: 37816584 PMCID: PMC10565674 DOI: 10.26508/lsa.202201856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 09/26/2023] [Accepted: 09/27/2023] [Indexed: 10/12/2023] Open
Abstract
Defects in ribosomal biogenesis profoundly affect organismal development and cellular function, and these ribosomopathies produce a variety of phenotypes. One ribosomopathy, Shwachman-Diamond syndrome (SDS) is characterized by neutropenia, pancreatic exocrine insufficiency, and skeletal anomalies. SDS results from biallelic mutations in SBDS, which encodes a ribosome assembly factor. Some individuals express a missense mutation, SBDS R126T , along with the common K62X mutation. We reported that the sbds-null zebrafish phenocopies much of SDS. We further showed activation of Tp53-dependent pathways before the fish died during the larval stage. Here, we expressed SBDS R126T as a transgene in the sbds -/- background. We showed that one copy of the SBDS R126T transgene permitted the establishment of maternal zygotic sbds-null fish which produced defective embryos with cdkn1a up-regulation, a Tp53 target involved in cell cycle arrest. None survived beyond 3 dpf. However, two copies of the transgene resulted in normal development and lifespan. Surprisingly, neutropenia persisted. The surviving fish displayed suppression of female sex differentiation, a stress response in zebrafish. To evaluate the role of Tp53 in the pathogenesis of sbds -/- fish phenotype, we bred the fish with a DNA binding deficient allele, tp53 M214K Expression of the loss-of-function tp53 M214K did not rescue neutropenia or survival in sbds-null zebrafish. Increased expression of cdkn1a was abrogated in the tp53 M214K/M214K ;sbds -/- fish. We conclude that the amount of SBDSR126T protein is important for development, inactivation of Tp53 fails to rescue neutropenia or survival in the sbds-null background, and cdkn1a up-regulation was dependent on WT tp53 We hypothesize that additional pathways are involved in the pathophysiology of SDS.
Collapse
Affiliation(s)
- Usua Oyarbide
- https://ror.org/03xjacd83 Departments of Cancer Biology and Pediatrics, Cleveland Clinic, Cleveland, OH, USA
| | - Arish N Shah
- Department of Biology and David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Morgan Staton
- https://ror.org/03xjacd83 Departments of Cancer Biology and Pediatrics, Cleveland Clinic, Cleveland, OH, USA
| | - Matthew Snyderman
- https://ror.org/03xjacd83 Departments of Cancer Biology and Pediatrics, Cleveland Clinic, Cleveland, OH, USA
| | - Adya Sapra
- https://ror.org/03xjacd83 Departments of Cancer Biology and Pediatrics, Cleveland Clinic, Cleveland, OH, USA
| | - Eliezer Calo
- Department of Biology and David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Seth J Corey
- https://ror.org/03xjacd83 Departments of Cancer Biology and Pediatrics, Cleveland Clinic, Cleveland, OH, USA
| |
Collapse
|
3
|
Al-Abri M, Kharousi KA, Hamrashdi AA, Toobi AGA, Salem MM. Genome wide association analysis for twinning ability in Jabal Akhdar Omani goats. Small Rumin Res 2023. [DOI: 10.1016/j.smallrumres.2023.106951] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
|
4
|
Counteracting the Common Shwachman-Diamond Syndrome-Causing SBDS c.258+2T>C Mutation by RNA Therapeutics and Base/Prime Editing. Int J Mol Sci 2023; 24:ijms24044024. [PMID: 36835434 PMCID: PMC9962285 DOI: 10.3390/ijms24044024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 02/09/2023] [Accepted: 02/11/2023] [Indexed: 02/19/2023] Open
Abstract
Shwachman-Diamond syndrome (SDS) represents one of the most common inherited bone marrow failure syndromes and is mainly caused by SBDS gene mutations. Only supportive treatments are available, with hematopoietic cell transplantation required when marrow failure occurs. Among all causative mutations, the SBDS c.258+2T>C variant at the 5' splice site (ss) of exon 2 is one of the most frequent. Here, we investigated the molecular mechanisms underlying aberrant SBDS splicing and showed that SBDS exon 2 is dense in splicing regulatory elements and cryptic splice sites, complicating proper 5'ss selection. Studies ex vivo and in vitro demonstrated that the mutation alters splicing, but it is also compatible with tiny amounts of correct transcripts, which would explain the survival of SDS patients. Moreover, for the first time for SDS, we explored a panel of correction approaches at the RNA and DNA levels and provided experimental evidence that the mutation effect can be partially counteracted by engineered U1snRNA, trans-splicing, and base/prime editors, ultimately leading to correctly spliced transcripts (from barely detectable to 2.5-5.5%). Among them, we propose DNA editors that, by stably reverting the mutation and potentially conferring positive selection to bone-marrow cells, could lead to the development of an innovative SDS therapy.
Collapse
|
5
|
Zhang M, Li K, Qu S, Guo Z, Wang Y, Yang X, Zhou J, Ouyang G, Weng R, Li F, Wu Y, Yang X. Integrative analyses of maternal plasma cell-free DNA nucleosome footprint differences reveal chromosomal aneuploidy fetuses gene expression profile. J Transl Med 2022; 20:536. [PMID: 36401256 PMCID: PMC9673457 DOI: 10.1186/s12967-022-03735-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 10/30/2022] [Indexed: 11/19/2022] Open
Abstract
Background Chromosomal aneuploidy is the most common birth defect. However, the developmental mechanism and gene expression profile of fetuses with chromosomal aneuploidy are relatively unknown, and the maternal immune changes induced by fetal aneuploidy remain unclear. The inability to obtain the placenta multiple times in real-time is a bottleneck in research on aneuploid pregnancies. Plasma cell-free DNA (cfDNA) carries the gene expression profile information of its source cells and may be used to evaluate the development of fetuses with aneuploidy and the immune changes induced in the mother owing to fetal aneuploidy. Methods Here, we carried out whole-genome sequencing of the plasma cfDNA of 101 pregnant women carrying a fetus with trisomy (trisomy 21, n = 42; trisomy 18, n = 28; trisomy 13, n = 31) based on non-invasive prenatal testing (NIPT) screening and 140 normal pregnant women to identify differential genes according to the cfDNA nucleosome profile in the region around the transcription start sites (TSSs). Results The plasma cfDNA promoter profiles were found to differ between aneuploid and euploid pregnancies. A total of 158 genes with significant differences were identified, of which 43 genes were upregulated and 98 genes were downregulated. Functional enrichment and signaling pathway analysis were performed based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases found that these signal pathways were mainly related to the coordination of developmental signals during embryonic development, the control of cell growth and development, regulation of neuronal survival, and immune regulation, such as the MAPK, Hippo, TGF-β, and Rap1 signaling pathways, which play important roles in the development of embryonic tissues and organs. Furthermore, based on the results of differential gene analysis, a total of 14 immune-related genes with significant differences from the ImmPort database were collected and analyzed. These significantly different immune genes were mainly associated with the maintenance of embryonic homeostasis and normal development. Conclusions These results suggest that the distribution characteristics of cfDNA nucleosomes in maternal plasma can be used to reflect the status of fetal development and changes of the immune responses in trisomic pregnancies. Overall, our findings may provide research ideas for non-invasive detection of the physiological and pathological states of other diseases. Supplementary Information The online version contains supplementary material available at 10.1186/s12967-022-03735-7.
Collapse
|
6
|
SBDS interacts with RNF2 and is degraded through RNF2-dependent ubiquitination. Biochem Biophys Res Commun 2022; 598:119-123. [DOI: 10.1016/j.bbrc.2022.02.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 02/05/2022] [Indexed: 11/20/2022]
|
7
|
Jaako P, Faille A, Tan S, Wong CC, Escudero-Urquijo N, Castro-Hartmann P, Wright P, Hilcenko C, Adams DJ, Warren AJ. eIF6 rebinding dynamically couples ribosome maturation and translation. Nat Commun 2022; 13:1562. [PMID: 35322020 PMCID: PMC8943182 DOI: 10.1038/s41467-022-29214-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 03/03/2022] [Indexed: 02/05/2023] Open
Abstract
Protein synthesis is a cyclical process consisting of translation initiation, elongation, termination and ribosome recycling. The release factors SBDS and EFL1—both mutated in the leukemia predisposition disorder Shwachman-Diamond syndrome — license entry of nascent 60S ribosomal subunits into active translation by evicting the anti-association factor eIF6 from the 60S intersubunit face. We find that in mammalian cells, eIF6 holds all free cytoplasmic 60S subunits in a translationally inactive state and that SBDS and EFL1 are the minimal components required to recycle these 60S subunits back into additional rounds of translation by evicting eIF6. Increasing the dose of eIF6 in mice in vivo impairs terminal erythropoiesis by sequestering post-termination 60S subunits in the cytoplasm, disrupting subunit joining and attenuating global protein synthesis. These data reveal that ribosome maturation and recycling are dynamically coupled by a mechanism that is disrupted in an inherited leukemia predisposition disorder. Jaako et al. discover a conserved tier of translational control that dynamically couples ribosome assembly and recycling. This mechanism is corrupted in an inherited bone marrow failure disorder associated with an increased risk of blood cancer.
Collapse
Affiliation(s)
- Pekka Jaako
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust-Medical Research Council Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.,Department of Haematology, University of Cambridge School of Clinical Medicine, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.,Sahlgrenska Center for Cancer Research, Department of Microbiology and Immunology, Institute of Biomedicine, University of Gothenburg, 413 90, Gothenburg, Sweden
| | - Alexandre Faille
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust-Medical Research Council Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.,Department of Haematology, University of Cambridge School of Clinical Medicine, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK
| | - Shengjiang Tan
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust-Medical Research Council Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.,Department of Haematology, University of Cambridge School of Clinical Medicine, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK
| | - Chi C Wong
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Department of Pathology, Cambridge University Hospitals, Hills Road, Cambridge, CB2 0QQ, UK
| | - Norberto Escudero-Urquijo
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust-Medical Research Council Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.,Department of Haematology, University of Cambridge School of Clinical Medicine, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK
| | - Pablo Castro-Hartmann
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust-Medical Research Council Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.,Department of Haematology, University of Cambridge School of Clinical Medicine, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK
| | - Penny Wright
- Department of Pathology, Cambridge University Hospitals, Hills Road, Cambridge, CB2 0QQ, UK
| | - Christine Hilcenko
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK.,Wellcome Trust-Medical Research Council Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.,Department of Haematology, University of Cambridge School of Clinical Medicine, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK
| | - David J Adams
- Experimental Cancer Genetics, Wellcome Trust Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridgeshire, CB10 1SA, UK
| | - Alan J Warren
- Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Keith Peters Building, Hills Rd, Cambridge, CB2 0XY, UK. .,Wellcome Trust-Medical Research Council Stem Cell Institute, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK. .,Department of Haematology, University of Cambridge School of Clinical Medicine, Jeffrey Cheah Biomedical Centre, Puddicombe Way, Cambridge Biomedical Campus, Cambridge, CB2 0AW, UK.
| |
Collapse
|
8
|
Frattini A, Bolamperti S, Valli R, Cipolli M, Pinto RM, Bergami E, Frau MR, Cesaro S, Signo M, Bezzerri V, Porta G, Khan AW, Rubinacci A, Villa I. Enhanced p53 Levels Are Involved in the Reduced Mineralization Capacity of Osteoblasts Derived from Shwachman-Diamond Syndrome Subjects. Int J Mol Sci 2021; 22:ijms222413331. [PMID: 34948128 PMCID: PMC8707819 DOI: 10.3390/ijms222413331] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 11/25/2021] [Accepted: 12/09/2021] [Indexed: 12/12/2022] Open
Abstract
Shwachman-Diamond syndrome (SDS) is a rare autosomal recessive disorder characterized by bone marrow failure, exocrine pancreatic insufficiency, and skeletal abnormalities, caused by loss-of-function mutations in the SBDS gene, a factor involved in ribosome biogenesis. By analyzing osteoblasts from SDS patients (SDS-OBs), we show that SDS-OBs displayed reduced SBDS gene expression and reduced/undetectable SBDS protein compared to osteoblasts from healthy subjects (H-OBs). SDS-OBs cultured in an osteogenic medium displayed a lower mineralization capacity compared to H-OBs. Whole transcriptome analysis showed significant differences in the gene expression of SDS-OBs vs. H-OBs, particularly in the ossification pathway. SDS-OBs expressed lower levels of the main genes responsible for osteoblastogenesis. Of all downregulated genes, Western blot analyses confirmed lower levels of alkaline phosphatase and collagen type I in SDS-OBs than in H-OBs. Interestingly, SDS-OBs showed higher protein levels of p53, an inhibitor of osteogenesis, compared to H-OBs. Silencing of Tp53 was associated with higher collagen type I and alkaline phosphatase protein levels and an increase in SDS-OB mineralization capacity. In conclusion, our results show that the reduced capacity of SDS-OBs to mineralize is mediated, at least in part, by the high levels of p53 and highlight an important role of SBDS in osteoblast functions.
Collapse
Affiliation(s)
- Annalisa Frattini
- Institute for Genetic and Biomedical Research (IRGB), UOS Milano CNR, Via Fantoli, 15/16, 20138 Milano, Italy
- Department of Medicine and Surgery (DMC), Universita’ degli Studi dell’Insubria, Via J.H. Dunant, 5, 21100 Varese, Italy; (R.V.); (G.P.); (A.W.K.)
- Correspondence: ; Tel.: +39-0332217113
| | - Simona Bolamperti
- Bone Metabolism Unit, IRCCS Ospedale San Raffaele, Via Olgettina, 60, 20132 Milano, Italy; (S.B.); (M.S.); (A.R.); (I.V.)
| | - Roberto Valli
- Department of Medicine and Surgery (DMC), Universita’ degli Studi dell’Insubria, Via J.H. Dunant, 5, 21100 Varese, Italy; (R.V.); (G.P.); (A.W.K.)
| | - Marco Cipolli
- Cystic Fibrosis Center, Azienda Ospedaliera Universitaria Integrata di Verona, Piazzale Aristide Stefani, 1, 37126 Verona, Italy;
| | - Rita Maria Pinto
- Department of Onco-Hematology, Ospedale Bambino Gesù IRCCS, Piazza S.Onofrio, 4, 00165 Roma, Italy;
| | - Elena Bergami
- Pediatric Onco-Hematology, IRCCS Policlinico San Matteo, Viale Camillo Golgi, 19, 27100 Pavia, Italy;
| | - Maria Rita Frau
- Pediatrics and Intensive Neonatal Therapy, Ospedale San Francesco, Via Salvatore Mannironi, 08100 Nuoro, Italy;
| | - Simone Cesaro
- Pediatric Hematology Oncology, Ospedale Donna Bambino, Azienda Ospedaliera Universitaria Integrata, Piazzale Aristide Stefani, 1, 37126 Verona, Italy;
| | - Michela Signo
- Bone Metabolism Unit, IRCCS Ospedale San Raffaele, Via Olgettina, 60, 20132 Milano, Italy; (S.B.); (M.S.); (A.R.); (I.V.)
| | - Valentino Bezzerri
- Cystic Fibrosis Center, Azienda Ospedaliero Universitaria Ospedali Riuniti di Ancona, Via Conca, 71, 60126 Ancona, Italy;
| | - Giovanni Porta
- Department of Medicine and Surgery (DMC), Universita’ degli Studi dell’Insubria, Via J.H. Dunant, 5, 21100 Varese, Italy; (R.V.); (G.P.); (A.W.K.)
| | - Abdul Waheed Khan
- Department of Medicine and Surgery (DMC), Universita’ degli Studi dell’Insubria, Via J.H. Dunant, 5, 21100 Varese, Italy; (R.V.); (G.P.); (A.W.K.)
| | - Alessandro Rubinacci
- Bone Metabolism Unit, IRCCS Ospedale San Raffaele, Via Olgettina, 60, 20132 Milano, Italy; (S.B.); (M.S.); (A.R.); (I.V.)
| | - Isabella Villa
- Bone Metabolism Unit, IRCCS Ospedale San Raffaele, Via Olgettina, 60, 20132 Milano, Italy; (S.B.); (M.S.); (A.R.); (I.V.)
| |
Collapse
|
9
|
Hematologic Complications with Age in Shwachman-Diamond Syndrome. Blood Adv 2021; 6:297-306. [PMID: 34758064 PMCID: PMC8753194 DOI: 10.1182/bloodadvances.2021005539] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 10/06/2021] [Indexed: 11/20/2022] Open
Abstract
Severe bone marrow failure was primarily observed in early childhood in children with biallelic SBDS mutations. Absolute neutrophil counts were positively associated with age (P < .0001) in patients with biallelic SBDS mutations.
Shwachman-Diamond syndrome (SDS) is an inherited bone marrow failure syndrome with leukemia predisposition. An understanding of the hematologic complications of SDS with age could guide clinical management, but data are limited for this rare disease. We conducted a cohort study of 153 subjects from 143 families with confirmed biallelic SBDS mutations enrolled on the North American Shwachman Diamond Registry or Bone Marrow Failure Registry. The SBDS c.258 + 2T>C variant was present in all but 1 patient. To evaluate the association between blood counts and age, 2146 blood counts were analyzed for 119 subjects. Absolute neutrophil counts were positively associated with age (P < .0001). Hemoglobin was also positively associated with age up to 18 years (P < .0001), but the association was negative thereafter (P = .0079). Platelet counts and marrow cellularity were negatively associated with age (P < .0001). Marrow cellularity did not correlate with blood counts. Severe marrow failure necessitating transplant developed in 8 subjects at a median age of 1.7 years (range, 0.4-39.5), with 7 of 8 requiring transplant prior to age 8 years. Twenty-six subjects (17%) developed a myeloid malignancy (16 myelodysplasia and 10 acute myeloid leukemia) at a median age of 12.3 years (range, 0.5-45.0) and 28.4 years (range, 14.4-47.3), respectively. A lymphoid malignancy developed in 1 patient at the age of 16.9 years. Hematologic complications were the major cause of mortality (17/20 deaths; 85%). These data inform surveillance of hematologic complications in SDS.
Collapse
|
10
|
Kumar S, Nattamai KJ, Hassan A, Amoah A, Karns R, Zhang C, Liang Y, Shimamura A, Florian MC, Bissels U, Luevano M, Bosio A, Davies SM, Mulaw M, Geiger H, Myers KC. Repolarization of HSC attenuates HSCs failure in Shwachman-Diamond syndrome. Leukemia 2021; 35:1751-1762. [PMID: 33077869 DOI: 10.1038/s41375-020-01054-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 08/11/2020] [Accepted: 10/05/2020] [Indexed: 01/01/2023]
Abstract
Shwachman-Diamond syndrome (SDS) is a bone marrow failure (BMF) syndrome associated with an increased risk of myelodysplasia and leukemia. The molecular mechanisms of SDS are not fully understood. We report that primitive hematopoietic cells from SDS patients present with a reduced activity of the small RhoGTPase Cdc42 and concomitantly a reduced frequency of HSCs polar for polarity proteins. The level of apolarity of SDS HSCs correlated with the magnitude of HSC depletion in SDS patients. Importantly, exogenously provided Wnt5a or GDF11 that elevates the activity of Cdc42 restored polarity in SDS HSCs and increased the number of HSCs in SDS patient samples in surrogate ex vivo assays. Single cell level RNA-Seq analyses of SDS HSCs and daughter cells demonstrated that SDS HSC treated with GDF11 are transcriptionally more similar to control than to SDS HSCs. Treatment with GDF11 reverted pathways in SDS HSCs associated with rRNA processing and ribosome function, but also viral infection and immune function, p53-dependent DNA damage, spindle checkpoints, and metabolism, further implying a role of these pathways in HSC failure in SDS. Our data suggest that HSC failure in SDS is driven at least in part by low Cdc42 activity in SDS HSCs. Our data thus identify novel rationale approaches to attenuate HSCs failure in SDS.
Collapse
Affiliation(s)
- Sachin Kumar
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Research Foundation, Cincinnati, OH, 45229, USA
- Pharmacology Division, CSIR-Central Drug Research Institute, Lucknow, 226031, India
| | - Kalpana J Nattamai
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Research Foundation, Cincinnati, OH, 45229, USA
| | - Aishlin Hassan
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Research Foundation, Cincinnati, OH, 45229, USA
| | - Amanda Amoah
- Institute of Molecular Medicine, Ulm University, Ulm, Germany
| | - Rebekah Karns
- Division of Gastroenterology, Hepatology and Nutrition, Cincinnati Children's Hospital Medical Center and University of Cincinnati, Cincinnati, OH, USA
| | - Cuiping Zhang
- Department of Toxicology and Cancer Biology, University of Kentucky, Health Sciences Research Building, Room 340, 1095 V.A. Drive, Lexington, KY, 40536, USA
| | - Ying Liang
- Department of Toxicology and Cancer Biology, University of Kentucky, Health Sciences Research Building, Room 340, 1095 V.A. Drive, Lexington, KY, 40536, USA
| | - Akiko Shimamura
- Boston Children's Hospital, Dana Farber Cancer Institute, Boston, MA, USA
| | | | - Ute Bissels
- Miltenyi Biotec GmbH, Bergisch Gladbach, Germany
| | | | | | - Stella M Davies
- Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Medhanie Mulaw
- Institute of Experimental Cancer Research, Ulm University, Ulm, Germany
| | - Hartmut Geiger
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Research Foundation, Cincinnati, OH, 45229, USA.
| | - Kasiani C Myers
- Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.
| |
Collapse
|
11
|
Takai A, Chiyonobu T, Ueoka I, Tanaka R, Tozawa T, Yoshida H, Morimoto M, Hosoi H, Yamaguchi M. A novel Drosophila model for neurodevelopmental disorders associated with Shwachman-Diamond syndrome. Neurosci Lett 2020; 739:135449. [PMID: 33115644 DOI: 10.1016/j.neulet.2020.135449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 09/19/2020] [Accepted: 10/08/2020] [Indexed: 10/23/2022]
Abstract
Genetic defects in ribosome biogenesis result in a group of diseases called ribosomopathies. Patients with ribosomopathies manifest multiorgan phenotypes, including neurological impairments. A well-characterized ribosomopathy, Shwachman-Diamond syndrome (SDS), is mainly associated with loss-of-function mutations in the causal gene SBDS. Children with SDS have neurodevelopmental disorders; however, the neurological consequences of SBDS dysfunction remain poorly defined. In the present study, we investigated the phenotype of Drosophila melanogaster following knockdown of CG8549, the Drosophila ortholog of human SBDS, to provide evidence for the neurological consequences of reduction in physiological SBDS functions. The pan-neuron-specific knockdown of CG8549 was associated with locomotive disabilities, mechanically induced seizures, hyperactivity, learning impairments, and anatomical defects in presynaptic terminals. These results provide the first evidence of a direct link between a reduction in physiological SBDS function and neurological impairments.
Collapse
Affiliation(s)
- Akari Takai
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Tomohiro Chiyonobu
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
| | - Ibuki Ueoka
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Ryo Tanaka
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Takenori Tozawa
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Hideki Yoshida
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
| | - Masafumi Morimoto
- Department of Medical Science, School of Nursing, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan
| | - Hajime Hosoi
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Masamitsu Yamaguchi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| |
Collapse
|
12
|
Hamabata T, Umeda K, Kouzuki K, Tanaka T, Daifu T, Nodomi S, Saida S, Kato I, Baba S, Hiramatsu H, Osawa M, Niwa A, Saito MK, Kamikubo Y, Adachi S, Hashii Y, Shimada A, Watanabe H, Osafune K, Okita K, Nakahata T, Watanabe K, Takita J, Heike T. Pluripotent stem cell model of Shwachman-Diamond syndrome reveals apoptotic predisposition of hemoangiogenic progenitors. Sci Rep 2020; 10:14859. [PMID: 32908229 PMCID: PMC7481313 DOI: 10.1038/s41598-020-71844-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 08/11/2020] [Indexed: 11/09/2022] Open
Abstract
Shwachman-Diamond syndrome (SDS), an autosomal recessive disorder characterized by bone marrow failure, exocrine pancreatic insufficiency, and skeletal abnormalities, is caused by mutations in the Shwachman-Bodian-Diamond syndrome (SBDS) gene, which plays a role in ribosome biogenesis. Although the causative genes of congenital disorders frequently involve regulation of embryogenesis, the role of the SBDS gene in early hematopoiesis remains unclear, primarily due to the lack of a suitable experimental model for this syndrome. In this study, we established induced pluripotent stem cells (iPSCs) from patients with SDS (SDS-iPSCs) and analyzed their in vitro hematopoietic and endothelial differentiation potentials. SDS-iPSCs generated hematopoietic and endothelial cells less efficiently than iPSCs derived from healthy donors, principally due to the apoptotic predisposition of KDR+CD34+ common hemoangiogenic progenitors. By contrast, forced expression of SBDS gene in SDS-iPSCs or treatment with a caspase inhibitor reversed the deficiency in hematopoietic and endothelial development, and decreased apoptosis of their progenitors, mainly via p53-independent mechanisms. Patient-derived iPSCs exhibited the hematological abnormalities associated with SDS even at the earliest hematopoietic stages. These findings will enable us to dissect the pathogenesis of multiple disorders associated with ribosomal dysfunction.
Collapse
Affiliation(s)
- Takayuki Hamabata
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Katsutsugu Umeda
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan.
| | - Kagehiro Kouzuki
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Takayuki Tanaka
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Tomoo Daifu
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Seishiro Nodomi
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Satoshi Saida
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Itaru Kato
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Shiro Baba
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Hidefumi Hiramatsu
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Mitsujiro Osawa
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, Kyoto, 606-8507, Japan
| | - Akira Niwa
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, Kyoto, 606-8507, Japan
| | - Megumu K Saito
- Department of Clinical Application, Center for iPS Cell Research and Application, Kyoto University, Kyoto, 606-8507, Japan
| | - Yasuhiko Kamikubo
- Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Souichi Adachi
- Department of Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, 606-8507, Japan
| | - Yoshiko Hashii
- Department of Cancer Immunotherapy, Osaka University School of Medicine, Suita, 565-0871, Japan
| | - Akira Shimada
- Department of Pediatric Hematology/Oncology, Okayama University, Okayama, 700-8558, Japan
| | - Hiroyoshi Watanabe
- Department of Pediatrics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima, 770-8501, Japan
| | - Kenji Osafune
- Department of Cell Growth and Differentiation, Center for iPS Cell Research and Application, Kyoto University, Kyoto, 606-8507, Japan
| | - Keisuke Okita
- Department of Life Science Frontiers, Center for iPS Cell Research and Application, Kyoto University, Kyoto, 606-8507, Japan
| | - Tatsutoshi Nakahata
- Drug Discovery Technology Development Office, Center for iPS Cell Research and Application, Kyoto University, Kyoto, 606-8507, Japan
| | - Kenichiro Watanabe
- Department of Hematology and Oncology, Shizuoka Children's Hospital, Shizuoka, 420-8660, Japan
| | - Junko Takita
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| | - Toshio Heike
- Department of Pediatrics, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto, 606-8507, Japan
| |
Collapse
|
13
|
Oyarbide U, Shah AN, Amaya-Mejia W, Snyderman M, Kell MJ, Allende DS, Calo E, Topczewski J, Corey SJ. Loss of Sbds in zebrafish leads to neutropenia and pancreas and liver atrophy. JCI Insight 2020; 5:134309. [PMID: 32759502 PMCID: PMC7526460 DOI: 10.1172/jci.insight.134309] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 07/29/2020] [Indexed: 01/29/2023] Open
Abstract
Shwachman-Diamond syndrome (SDS) is characterized by exocrine pancreatic insufficiency, neutropenia, and skeletal abnormalities. Biallelic mutations in SBDS, which encodes a ribosome maturation factor, are found in 90% of SDS cases. Sbds–/– mice are embryonic lethal. Using CRISPR/Cas9 editing, we created sbds-deficient zebrafish strains. Sbds protein levels progressively decreased and became undetectable at 10 days postfertilization (dpf). Polysome analysis revealed decreased 80S ribosomes. Homozygous mutant fish developed normally until 15 dpf. Mutant fish subsequently had stunted growth and showed signs of atrophy in pancreas, liver, and intestine. In addition, neutropenia occurred by 5 dpf. Upregulation of tp53 mRNA did not occur until 10 dpf, and inhibition of proliferation correlated with death by 21 dpf. Transcriptome analysis showed tp53 activation through upregulation of genes involved in cell cycle arrest, cdkn1a and ccng1, and apoptosis, puma and mdm2. However, elimination of Tp53 function did not prevent lethality. Because of growth retardation and atrophy of intestinal epithelia, we studied the effects of starvation on WT fish. Starved WT fish showed intestinal atrophy, zymogen granule loss, and tp53 upregulation — similar to the mutant phenotype. In addition, there was reduction in neutral lipid storage and ribosomal protein amount, similar to the mutant phenotype. Thus, loss of Sbds in zebrafish phenocopies much of the human disease and is associated with growth arrest and tissue atrophy, particularly of the gastrointestinal system, at the larval stage. A variety of stress responses, some associated with Tp53, contribute to pathophysiology of SDS. Loss of ribosome maturation factor sbds in the zebrafish phenocopies human Shwachman-Diamond syndrome and is associated with p53 activation, but lethality cannot be rescued by p53 mutation.
Collapse
Affiliation(s)
- Usua Oyarbide
- Departments of Pediatrics, Immunology, and Human and Molecular Genetics, Children's Hospital of Richmond and Massey Cancer Center at Virginia Commonwealth University, Richmond, Virginia, USA.,Department of Pediatrics, Stanley Manne Children's Research Institute, Northwestern University School of Medicine, Chicago, Illinois, USA.,Departments of Pediatrics, Cancer Biology, and Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, Ohio, USA
| | - Arish N Shah
- Department of Biology and David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Wilmer Amaya-Mejia
- Departments of Pediatrics, Immunology, and Human and Molecular Genetics, Children's Hospital of Richmond and Massey Cancer Center at Virginia Commonwealth University, Richmond, Virginia, USA
| | - Matthew Snyderman
- Departments of Pediatrics, Cancer Biology, and Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, Ohio, USA
| | - Margaret J Kell
- Department of Pediatrics, Stanley Manne Children's Research Institute, Northwestern University School of Medicine, Chicago, Illinois, USA
| | | | - Eliezer Calo
- Department of Biology and David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Jacek Topczewski
- Department of Pediatrics, Stanley Manne Children's Research Institute, Northwestern University School of Medicine, Chicago, Illinois, USA.,Department of Biochemistry and Molecular Biology, Medical University of Lublin, Lublin, Poland
| | - Seth J Corey
- Departments of Pediatrics, Immunology, and Human and Molecular Genetics, Children's Hospital of Richmond and Massey Cancer Center at Virginia Commonwealth University, Richmond, Virginia, USA.,Department of Pediatrics, Stanley Manne Children's Research Institute, Northwestern University School of Medicine, Chicago, Illinois, USA.,Departments of Pediatrics, Cancer Biology, and Translational Hematology and Oncology Research, Cleveland Clinic, Cleveland, Ohio, USA
| |
Collapse
|
14
|
Lou F, Zhang Y, Song N, Ji D, Gao T. Comprehensive Transcriptome Analysis Reveals Insights into Phylogeny and Positively Selected Genes of Sillago Species. Animals (Basel) 2020; 10:ani10040633. [PMID: 32272562 PMCID: PMC7222750 DOI: 10.3390/ani10040633] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 03/31/2020] [Accepted: 04/01/2020] [Indexed: 01/09/2023] Open
Abstract
Sillago species lives in the demersal environments and face multiple stressors, such as localized oxygen depletion, sulfide accumulation, and high turbidity. In this study, we performed transcriptome analyses of seven Sillago species to provide insights into the phylogeny and positively selected genes of this species. After de novo assembly, 82,024, 58,102, 63,807, 85,990, 102,185, 69,748, and 102,903 unigenes were generated from S. japonica, S. aeolus, S. sp.1, S. sihama, S. sp.2, S. parvisquamis, and S. sinica, respectively. Furthermore, 140 shared orthologous exon markers were identified and then applied to reconstruct the phylogenetic relationships of the seven Sillago species. The reconstructed phylogenetic structure was significantly congruent with the prevailing morphological and molecular biological view of Sillago species relationships. In addition, a total of 44 genes were identified to be positively selected, and these genes were potential participants in the stress response, material (carbohydrate, amino acid and lipid) and energy metabolism, growth and differentiation, embryogenesis, visual sense, and other biological processes. We suspected that these genes possibly allowed Sillago species to increase their ecological adaptation to multiple environmental stressors.
Collapse
Affiliation(s)
- Fangrui Lou
- Fishery College, Zhejiang Ocean University, Zhoushan 316022, Zhejiang, China;
| | - Yuan Zhang
- Fishery College, Ocean University of China, Qingdao 266003, Shandong, China; (Y.Z.); (N.S.)
| | - Na Song
- Fishery College, Ocean University of China, Qingdao 266003, Shandong, China; (Y.Z.); (N.S.)
| | - Dongping Ji
- Agricultural Machinery Service Center, Fangchenggang 538000, Guangxi, China;
| | - Tianxiang Gao
- Fishery College, Zhejiang Ocean University, Zhoushan 316022, Zhejiang, China;
- Correspondence: ; Tel.: +86-580-2089-333
| |
Collapse
|
15
|
Hao Q, Wang J, Chen Y, Wang S, Cao M, Lu H, Zhou X. Dual regulation of p53 by the ribosome maturation factor SBDS. Cell Death Dis 2020; 11:197. [PMID: 32198344 PMCID: PMC7083877 DOI: 10.1038/s41419-020-2393-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 02/25/2020] [Accepted: 02/26/2020] [Indexed: 02/06/2023]
Abstract
The Shwachman-Bodian Diamond syndrome (SBDS)-associated gene, SBDS, is involved in rRNA synthesis and ribosome maturation, but the role of SBDS in cancer is largely elusive. In this study, we found that SBDS is often overexpressed or amplified in human cancers, and high level of endogenous SBDS is significantly associated with unfavorable prognosis. Conversely, knockdown of SBDS leads to p53 stabilization and activation through the ribosomal stress-RPL5/RPL11-MDM2 pathway, resulting in the repression of cancer cell proliferation and invasion. Interestingly, ectopic SBDS in the nucleoplasm also suppresses tumor cell growth and proliferation in vitro and in vivo. Mechanistically, ectopically expressed SBDS triggered by, for example, ribosomal stress binds to the transactivation domain of p53 and perturbs the MDM2-p53 interaction, consequently leading to impaired p53 ubiquitination and proteasomal degradation. Altogether, our finding for the first time demonstrates the dual functions of SBDS in cancer development by coordinating ribosome biogenesis and p53 activity.
Collapse
Affiliation(s)
- Qian Hao
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China. .,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.
| | - Jieqiong Wang
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China.,Department of Biochemistry & Molecular Biology, Tulane University School of Medicine, New Orleans, LA, 70112, USA
| | - Yajie Chen
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Shanshan Wang
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Mingming Cao
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China.,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China
| | - Hua Lu
- Department of Biochemistry & Molecular Biology and Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA, 70112, USA
| | - Xiang Zhou
- Fudan University Shanghai Cancer Center and Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China. .,Department of Oncology, Shanghai Medical College, Fudan University, Shanghai, 200032, China. .,The Shanghai Key Laboratory of Medical Epigenetics and the International Co-laboratory of Medical Epigenetics and Metabolism, Institutes of Biomedical Sciences, Fudan University, Shanghai, 200032, China. .,Key Laboratory of Breast Cancer in Shanghai, Fudan University Shanghai Cancer Center, Fudan University, Shanghai, 200032, China.
| |
Collapse
|
16
|
On-chip recapitulation of clinical bone marrow toxicities and patient-specific pathophysiology. Nat Biomed Eng 2020; 4:394-406. [PMID: 31988457 PMCID: PMC7160021 DOI: 10.1038/s41551-019-0495-z] [Citation(s) in RCA: 138] [Impact Index Per Article: 34.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2018] [Accepted: 11/22/2019] [Indexed: 12/27/2022]
Abstract
The inaccessibility of living bone marrow hampers the study of its pathophysiology under myelotoxic stress induced by drugs, radiation or genetic mutations. Here, we show that a vascularized human bone-marrow-on-a-chip supports the differentiation and maturation of multiple blood-cell lineages over 4 weeks while improving CD34+ cell maintenance, and that it recapitulates aspects of marrow injury, including myeloerythroid toxicity after clinically relevant exposures to chemotherapeutic drugs and ionizing radiation as well as marrow recovery after drug-induced myelosuppression. The chip comprises a fluidic channel filled with a fibrin gel in which CD34+ cells and bone-marrow-derived stromal cells are co-cultured, a parallel channel lined by human vascular endothelium and perfused with culture medium, and a porous membrane separating the two channels. We also show that bone-marrow chips containing cells from patients with the rare genetic disorder Shwachman–Diamond syndrome reproduced key haematopoietic defects and led to the discovery of a neutrophil-maturation abnormality. As an in vitro model of haematopoietic dysfunction, the bone-marrow-on-a-chip may serve as a human-specific alternative to animal testing for the study of bone-marrow pathophysiology.
Collapse
|
17
|
Bezzerri V, Cipolli M. Shwachman-Diamond Syndrome: Molecular Mechanisms and Current Perspectives. Mol Diagn Ther 2019; 23:281-290. [PMID: 30413969 DOI: 10.1007/s40291-018-0368-2] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Shwachman-Diamond syndrome (SDS) is a rare inherited disease mainly caused by mutations in the Shwachman-Bodian-Diamond Syndrome (SBDS) gene. However, it has recently been reported that other genes, including DnaJ heat shock protein family (Hsp40) member C21 (DNAJC21), elongation factor-like 1 (EFL1) and signal recognition particle 54 (SRP54) are also associated with an SDS-like phenotype. Interestingly, SBDS, DNAJC21, EFL1 and SRP54 are involved in ribosome biogenesis: SBDS, through direct interaction with EFL1, promotes the release of the eukaryotic initiation factor 6 (eIF6) during ribosome maturation, DNAJC21 stabilizes the 80S ribosome, and SRP54 facilitates protein trafficking. These findings strengthen the postulate that SDS is a ribosomopathy. SDS is a multiple-organ disease mainly characterized by bone marrow failure, bone malformations, pancreatic insufficiency and cognitive disorders. Almost 15-20% of patients with SDS present myelodysplastic syndrome with a high risk of acute myeloid leukemia (AML) transformation. Unfortunately, besides bone marrow transplantation, no gene-based therapy for SDS has yet been developed. This review aims to recapitulate the recent findings on the molecular mechanisms of SDS underlying bone marrow failure, hematopoiesis and AML development and to draw a realistic picture of current perspectives.
Collapse
Affiliation(s)
- Valentino Bezzerri
- Cystic Fibrosis Center, Azienda Ospedaliero Universitaria Ospedali Riuniti di Ancona, Via Conca 71, 60126, Torrette, Ancona, Italy
| | - Marco Cipolli
- Cystic Fibrosis Center, Azienda Ospedaliero Universitaria Ospedali Riuniti di Ancona, Via Conca 71, 60126, Torrette, Ancona, Italy.
| |
Collapse
|
18
|
Oyarbide U, Topczewski J, Corey SJ. Peering through zebrafish to understand inherited bone marrow failure syndromes. Haematologica 2018; 104:13-24. [PMID: 30573510 PMCID: PMC6312012 DOI: 10.3324/haematol.2018.196105] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Accepted: 11/14/2018] [Indexed: 12/22/2022] Open
Abstract
Inherited bone marrow failure syndromes are experiments of nature characterized by impaired hematopoiesis with cancer and leukemia predisposition. The mutations associated with inherited bone marrow failure syndromes affect fundamental cellular pathways, such as DNA repair, telomere maintenance, or proteostasis. How these disturbed pathways fail to produce sufficient blood cells and lead to leukemogenesis are not understood. The rarity of inherited cytopenias, the paucity of affected primary human hematopoietic cells, and the sometime inadequacy of murine or induced pluripotential stem cell models mean it is difficult to acquire a greater understanding of them. Zebrafish offer a model organism to study gene functions. As vertebrates, zebrafish share with humans many orthologous genes involved in blood disorders. As a model organism, zebrafish provide advantages that include rapid development of transparent embryos, high fecundity (providing large numbers of mutant and normal siblings), and a large collection of mutant and transgenic lines useful for investigating the blood system and other tissues during development. Importantly, recent advances in genomic editing in zebrafish can speedily validate the new genes or novel variants discovered in clinical investigation as causes for marrow failure. Here we review zebrafish as a model organism that phenocopies Fanconi anemia, Diamond-Blackfan anemia, dyskeratosis congenita, Shwachman-Diamond syndrome, congenital amegakaryocytic thrombocytopenia, and severe congenital neutropenia. Two important insights, provided by modeling inherited cytopenias in zebrafish, widen understanding of ribosome biogenesis and TP53 in mediating marrow failure and non-hematologic defects. They suggest that TP53-independent pathways contribute to marrow failure. In addition, zebrafish provide an attractive model organism for drug development.
Collapse
Affiliation(s)
- Usua Oyarbide
- Department of Pediatrics, Children's Hospital of Richmond and Massey Cancer Center at Virginia Commonwealth University, Richmond, VA, USA
| | - Jacek Topczewski
- Department of Pediatrics, Stanley Manne Children's Research Institute, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.,Department of Biochemistry and Molecular Biology, Medical University of Lublin, Poland
| | - Seth J Corey
- Department of Pediatrics, Children's Hospital of Richmond and Massey Cancer Center at Virginia Commonwealth University, Richmond, VA, USA .,Department of Microbiology/Immunology, Virginia Commonwealth University, USA.,Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, USA
| |
Collapse
|
19
|
Nelson AS, Myers KC. Diagnosis, Treatment, and Molecular Pathology of Shwachman-Diamond Syndrome. Hematol Oncol Clin North Am 2018; 32:687-700. [DOI: 10.1016/j.hoc.2018.04.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
|
20
|
Bezzerri V, Bardelli D, Morini J, Vella A, Cesaro S, Sorio C, Biondi A, Danesino C, Farruggia P, Assael BM, D'amico G, Cipolli M. Ataluren-driven restoration of Shwachman-Bodian-Diamond syndrome protein function in Shwachman-Diamond syndrome bone marrow cells. Am J Hematol 2018; 93:527-536. [PMID: 29285795 DOI: 10.1002/ajh.25025] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 12/21/2017] [Accepted: 12/26/2017] [Indexed: 12/31/2022]
Abstract
Shwachman-Diamond syndrome (SDS) is a rare inherited recessive disease mainly caused by mutations in the Shwachman-Bodian-Diamond syndrome (SBDS) gene, which encodes for the homonymous protein SBDS, whose function still remains to be fully established. SDS affects several organs causing bone marrow failure, exocrine pancreatic insufficiency, skeletal malformations, and cognitive disorders. About 15% of SDS patients develop myelodysplastic syndrome (MDS) and are at higher risk of developing acute myeloid leukemia (AML). Deficiency in SBDS expression has been associated with increased apoptosis and lack of myeloid differentiation in bone marrow hematopoietic progenitors. Importantly, most SDS patients carry nonsense mutations in SBDS. Since ataluren is a well-characterized small molecule inhibitor that can suppress nonsense mutations, here, we have assessed the efficacy of this drug in restoring SBDS expression in hematopoietic cells obtained from a cohort of SDS patients. Remarkably, we show that ataluren treatment readily restores SBDS protein expression in different cell types, particularly bone marrow stem cells. Furthermore, ataluren promotes myeloid differentiation in hematopoietic progenitors, reduces apoptotic rate in primary PBMCs, and brings mammalian target of rapamycin phosphorylation levels back to normal in both lymphoblasts and bone marrow mesenchymal stromal cells (BM-MSCs). Since a specific therapy against SDS is currently lacking, these results provide the rationale for ataluren repurposing clinical trials.
Collapse
Affiliation(s)
| | - Donatella Bardelli
- Unit of Immunology and Immunotherapy, Centro Ricerca Tettamanti, Pediatric Department; University of Milano Bicocca, Fondazione MBBM; Italy
| | | | - Antonio Vella
- Unit of Immunology; Azienda Ospedaliera Universitaria Integrata di Verona; Italy
| | - Simone Cesaro
- Unit of Pediatric Hematology Oncology; Azienda Ospedaliera Universitaria Integrata di Verona; Italy
| | | | - Andrea Biondi
- School of Medicine and Surgery; University of Milano-Bicocca; Italy
| | - Cesare Danesino
- Department of Molecular Medicine; University of Pavia; Italy
| | - Piero Farruggia
- Department of Oncology; ARNAS Ospedale Civico Palermo; Italy
| | - Baroukh Maurice Assael
- Department of Pulmonology; Adult CF center, IRCCS Fondazione Cà Granda; Policlinico Milano Italy
| | - Giovanna D'amico
- Unit of Immunology and Immunotherapy, Centro Ricerca Tettamanti, Pediatric Department; University of Milano Bicocca, Fondazione MBBM; Italy
| | - Marco Cipolli
- Cystic Fibrosis Center; Azienda Ospedaliero Universitaria Ospedali Riuniti; Ancona Italy
| |
Collapse
|
21
|
Sulima SO, Hofman IJF, De Keersmaecker K, Dinman JD. How Ribosomes Translate Cancer. Cancer Discov 2017; 7:1069-1087. [PMID: 28923911 PMCID: PMC5630089 DOI: 10.1158/2159-8290.cd-17-0550] [Citation(s) in RCA: 111] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 07/18/2017] [Accepted: 07/31/2017] [Indexed: 12/13/2022]
Abstract
A wealth of novel findings, including congenital ribosomal mutations in ribosomopathies and somatic ribosomal mutations in various cancers, have significantly increased our understanding of the relevance of ribosomes in oncogenesis. Here, we explore the growing list of mechanisms by which the ribosome is involved in carcinogenesis-from the hijacking of ribosomes by oncogenic factors and dysregulated translational control, to the effects of mutations in ribosomal components on cellular metabolism. Of clinical importance, the recent success of RNA polymerase inhibitors highlights the dependence on "onco-ribosomes" as an Achilles' heel of cancer cells and a promising target for further therapeutic intervention.Significance: The recent discovery of somatic mutations in ribosomal proteins in several cancers has strengthened the link between ribosome defects and cancer progression, while also raising the question of which cellular mechanisms such defects exploit. Here, we discuss the emerging molecular mechanisms by which ribosomes support oncogenesis, and how this understanding is driving the design of novel therapeutic strategies. Cancer Discov; 7(10); 1069-87. ©2017 AACR.
Collapse
Affiliation(s)
- Sergey O Sulima
- Department of Oncology, KU Leuven, University of Leuven, LKI, Leuven Cancer Institute, Leuven, Belgium
| | - Isabel J F Hofman
- Department of Oncology, KU Leuven, University of Leuven, LKI, Leuven Cancer Institute, Leuven, Belgium
| | - Kim De Keersmaecker
- Department of Oncology, KU Leuven, University of Leuven, LKI, Leuven Cancer Institute, Leuven, Belgium.
| | - Jonathan D Dinman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland.
| |
Collapse
|
22
|
Warren AJ. Molecular basis of the human ribosomopathy Shwachman-Diamond syndrome. Adv Biol Regul 2017; 67:109-127. [PMID: 28942353 PMCID: PMC6710477 DOI: 10.1016/j.jbior.2017.09.002] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 09/05/2017] [Indexed: 01/05/2023]
Abstract
Mutations that target the ubiquitous process of ribosome assembly paradoxically cause diverse tissue-specific disorders (ribosomopathies) that are often associated with an increased risk of cancer. Ribosomes are the essential macromolecular machines that read the genetic code in all cells in all kingdoms of life. Following pre-assembly in the nucleus, precursors of the large 60S and small 40S ribosomal subunits are exported to the cytoplasm where the final steps in maturation are completed. Here, I review the recent insights into the conserved mechanisms of ribosome assembly that have come from functional characterisation of the genes mutated in human ribosomopathies. In particular, recent advances in cryo-electron microscopy, coupled with genetic, biochemical and prior structural data, have revealed that the SBDS protein that is deficient in the inherited leukaemia predisposition disorder Shwachman-Diamond syndrome couples the final step in cytoplasmic 60S ribosomal subunit maturation to a quality control assessment of the structural and functional integrity of the nascent particle. Thus, study of this fascinating disorder is providing remarkable insights into how the large ribosomal subunit is functionally activated in the cytoplasm to enter the actively translating pool of ribosomes.
Collapse
MESH Headings
- Bone Marrow Diseases/metabolism
- Bone Marrow Diseases/pathology
- Cryoelectron Microscopy
- Exocrine Pancreatic Insufficiency/metabolism
- Exocrine Pancreatic Insufficiency/pathology
- Humans
- Lipomatosis/metabolism
- Lipomatosis/pathology
- Mutation
- Proteins/genetics
- Proteins/metabolism
- Ribosome Subunits, Large, Eukaryotic/genetics
- Ribosome Subunits, Large, Eukaryotic/metabolism
- Ribosome Subunits, Large, Eukaryotic/ultrastructure
- Ribosome Subunits, Small, Eukaryotic/genetics
- Ribosome Subunits, Small, Eukaryotic/metabolism
- Ribosome Subunits, Small, Eukaryotic/ultrastructure
- Shwachman-Diamond Syndrome
Collapse
Affiliation(s)
- Alan J Warren
- Cambridge Institute for Medical Research, Cambridge, UK; The Department of Haematology, University of Cambridge, Cambridge, UK; Wellcome Trust-Medical Research Council Stem Cell Institute, University of Cambridge, Cambridge, UK.
| |
Collapse
|
23
|
Affiliation(s)
- Roberto Valli
- Medical Genetic Unit, Department of Medicine and Surgery, University of Insubria, Varese, Italy
| | - Annalisa Frattini
- UOS Milano, Institute of Genetics and Biomedical Research, National Research Council, Milano, Italy
- Department of Medicine and Surgery, University of Insubria, Milano, Italy
| | - Antonella Minelli
- Medical Genetic Unit, Department of Molecular Medicine, University of Pavia, Pavia, Italy
| |
Collapse
|
24
|
Adam S, Melguizo Sanchis D, El-Kamah G, Samarasinghe S, Alharthi S, Armstrong L, Lako M. Concise Review: Getting to the Core of Inherited Bone Marrow Failures. Stem Cells 2016; 35:284-298. [PMID: 27870251 PMCID: PMC5299470 DOI: 10.1002/stem.2543] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Revised: 10/15/2016] [Accepted: 10/28/2016] [Indexed: 12/20/2022]
Abstract
Bone marrow failure syndromes (BMFS) are a group of disorders with complex pathophysiology characterized by a common phenotype of peripheral cytopenia and/or hypoplastic bone marrow. Understanding genetic factors contributing to the pathophysiology of BMFS has enabled the identification of causative genes and development of diagnostic tests. To date more than 40 mutations in genes involved in maintenance of genomic stability, DNA repair, ribosome and telomere biology have been identified. In addition, pathophysiological studies have provided insights into several biological pathways leading to the characterization of genotype/phenotype correlations as well as the development of diagnostic approaches and management strategies. Recent developments in bone marrow transplant techniques and the choice of conditioning regimens have helped improve transplant outcomes. However, current morbidity and mortality remain unacceptable underlining the need for further research in this area. Studies in mice have largely been unable to mimic disease phenotype in humans due to difficulties in fully replicating the human mutations and the differences between mouse and human cells with regard to telomere length regulation, processing of reactive oxygen species and lifespan. Recent advances in induced pluripotency have provided novel insights into disease pathogenesis and have generated excellent platforms for identifying signaling pathways and functional mapping of haplo‐insufficient genes involved in large‐scale chromosomal deletions–associated disorders. In this review, we have summarized the current state of knowledge in the field of BMFS with specific focus on modeling the inherited forms and how to best utilize these models for the development of targeted therapies. Stem Cells2017;35:284–298
Collapse
Affiliation(s)
- Soheir Adam
- Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.,Hematology Department, Medical School, King Abdulaziz University, Jeddah, KSA
| | | | - Ghada El-Kamah
- Division of Human Genetics & Genome Research, National Research Center, Cairo, Egypt
| | - Sujith Samarasinghe
- Department of Hematology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
| | - Sameer Alharthi
- Princess Al Jawhara Al-Brahim Center of Excellence in Research of Hereditary Disorders, King Abdulaziz University, KSA
| | - Lyle Armstrong
- Institute of Genetic Medicine, Newcastle University, United Kingdom
| | - Majlinda Lako
- Institute of Genetic Medicine, Newcastle University, United Kingdom
| |
Collapse
|
25
|
Ravera S, Dufour C, Cesaro S, Bottega R, Faleschini M, Cuccarolo P, Corsolini F, Usai C, Columbaro M, Cipolli M, Savoia A, Degan P, Cappelli E. Evaluation of energy metabolism and calcium homeostasis in cells affected by Shwachman-Diamond syndrome. Sci Rep 2016; 6:25441. [PMID: 27146429 PMCID: PMC4857091 DOI: 10.1038/srep25441] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 04/12/2016] [Indexed: 02/07/2023] Open
Abstract
Isomorphic mutation of the SBDS gene causes Shwachman-Diamond syndrome (SDS). SDS is a rare genetic bone marrow failure and cancer predisposition syndrome. SDS cells have ribosome biogenesis and their protein synthesis altered, which are two high-energy consuming cellular processes. The reported changes in reactive oxygen species production, endoplasmic reticulum stress response and reduced mitochondrial functionality suggest an energy production defect in SDS cells. In our work, we have demonstrated that SDS cells display a Complex IV activity impairment, which causes an oxidative phosphorylation metabolism defect, with a consequent decrease in ATP production. These data were confirmed by an increased glycolytic rate, which compensated for the energetic stress. Moreover, the signalling pathways involved in glycolysis activation also appeared more activated; i.e. we reported AMP-activated protein kinase hyper-phosphorylation. Notably, we also observed an increase in a mammalian target of rapamycin phosphorylation and high intracellular calcium concentration levels ([Ca(2+)]i), which probably represent new biochemical equilibrium modulation in SDS cells. Finally, the SDS cell response to leucine (Leu) was investigated, suggesting its possible use as a therapeutic adjuvant to be tested in clinical trials.
Collapse
Affiliation(s)
- Silvia Ravera
- DIFAR-Biochemistry Lab., Department of Pharmacy, University of Genova, 16132 Genova, Italy
| | - Carlo Dufour
- Haematology Unit, Istituto Giannina Gaslini, 16148 Genova, Italy
| | - Simone Cesaro
- Oncoematologia Pediatrica, Azienda Ospedaleira universitaria Integrata, Verona, Italy
| | - Roberta Bottega
- Department of Medical Sciences, University of Trieste, Trieste, Italy
| | - Michela Faleschini
- Institute for Maternal and Child Health – IRCCS Burlo Garofolo, Trieste, Italy
| | - Paola Cuccarolo
- S. C. Mutagenesis, IRCCS AOU San Martino – IST (Istituto Nazionale per la Ricerca sul Cancro), CBA Torre A2, 16123 Genova, Italy
| | - Fabio Corsolini
- Centro Diagnostica Genetica e Biochimica Malattie Metaboliche, Istituto Giannina Gaslini, 16148 Genova, Italy
| | - Cesare Usai
- Institute of Biophysics, National Research Council, 16149 Genova, Italy
| | - Marta Columbaro
- SC Laboratory of Musculoskeletal Cell Biology, IOR, Bologna, Italy
| | - Marco Cipolli
- Cystic Fibrosis Centre, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| | - Anna Savoia
- Institute for Maternal and Child Health – IRCCS Burlo Garofolo, Trieste, Italy
- Department of Medical Sciences, University of Trieste, Trieste, Italy
| | - Paolo Degan
- S. C. Mutagenesis, IRCCS AOU San Martino – IST (Istituto Nazionale per la Ricerca sul Cancro), CBA Torre A2, 16123 Genova, Italy
| | - Enrico Cappelli
- Haematology Unit, Istituto Giannina Gaslini, 16148 Genova, Italy
| |
Collapse
|
26
|
De Keersmaecker K. A novel mouse model provides insights into the neutropenia associated with the ribosomopathy Shwachman-Diamond syndrome. Haematologica 2016; 100:1237-9. [PMID: 26432381 DOI: 10.3324/haematol.2015.133777] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Kim De Keersmaecker
- KU Leuven Department of Oncology, Leuven, Belgium VIB Center for the Biology of Disease, Leuven, Belgium
| |
Collapse
|
27
|
In K, Zaini MA, Müller C, Warren AJ, von Lindern M, Calkhoven CF. Shwachman-Bodian-Diamond syndrome (SBDS) protein deficiency impairs translation re-initiation from C/EBPα and C/EBPβ mRNAs. Nucleic Acids Res 2016; 44:4134-46. [PMID: 26762974 PMCID: PMC4872075 DOI: 10.1093/nar/gkw005] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 12/31/2015] [Indexed: 01/24/2023] Open
Abstract
Mutations in the Shwachman–Bodian–Diamond Syndrome (SBDS) gene cause Shwachman–Diamond Syndrome (SDS), a rare congenital disease characterized by bone marrow failure with neutropenia, exocrine pancreatic dysfunction and skeletal abnormalities. The SBDS protein is important for ribosome maturation and therefore SDS belongs to the ribosomopathies. It is unknown, however, if loss of SBDS functionality affects the translation of specific mRNAs and whether this could play a role in the development of the clinical features of SDS. Here, we report that translation of the C/EBPα and -β mRNAs, that are indispensible regulators of granulocytic differentiation, is altered by SBDS mutations or knockdown. We show that SBDS function is specifically required for efficient translation re-initiation into the protein isoforms C/EBPα-p30 and C/EBPβ-LIP, which is controlled by a single cis-regulatory upstream open reading frame (uORF) in the 5′ untranslated regions (5′ UTRs) of both mRNAs. Furthermore, we show that as a consequence of the C/EBPα and -β deregulation the expression of MYC is decreased with associated reduction in proliferation, suggesting that failure of progenitor proliferation contributes to the haematological phenotype of SDS. Therefore, our study provides the first indication that disturbance of specific translation by loss of SBDS function may contribute to the development of the SDS phenotype.
Collapse
Affiliation(s)
- Kyungmin In
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstrasse 11, D-07745 Jena, Germany
| | - Mohamad A Zaini
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstrasse 11, D-07745 Jena, Germany European Institute for the Biology of Ageing (ERIBA), University Medical Center Groningen, University of Groningen, 9700 AD, Groningen, The Netherlands
| | - Christine Müller
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstrasse 11, D-07745 Jena, Germany European Institute for the Biology of Ageing (ERIBA), University Medical Center Groningen, University of Groningen, 9700 AD, Groningen, The Netherlands
| | - Alan J Warren
- Cambridge Institute for Medical Research, Wellcome Trust-Medical Research Council Stem Cell Institute, the Department of Haematology, University of Cambridge, CB2 0XY, Cambridge, UK
| | - Marieke von Lindern
- Sanquin Research and Landsteiner Laboratory, Department of Hematopoiesis, 1066 CX Amsterdam, The Netherlands
| | - Cornelis F Calkhoven
- Leibniz Institute on Aging - Fritz Lipmann Institute, Beutenbergstrasse 11, D-07745 Jena, Germany European Institute for the Biology of Ageing (ERIBA), University Medical Center Groningen, University of Groningen, 9700 AD, Groningen, The Netherlands
| |
Collapse
|
28
|
Zambetti NA, Bindels EMJ, Van Strien PMH, Valkhof MG, Adisty MN, Hoogenboezem RM, Sanders MA, Rommens JM, Touw IP, Raaijmakers MHGP. Deficiency of the ribosome biogenesis gene Sbds in hematopoietic stem and progenitor cells causes neutropenia in mice by attenuating lineage progression in myelocytes. Haematologica 2015; 100:1285-93. [PMID: 26185170 DOI: 10.3324/haematol.2015.131573] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 07/06/2015] [Indexed: 01/10/2023] Open
Abstract
Shwachman-Diamond syndrome is a congenital bone marrow failure disorder characterized by debilitating neutropenia. The disease is associated with loss-of-function mutations in the SBDS gene, implicated in ribosome biogenesis, but the cellular and molecular events driving cell specific phenotypes in ribosomopathies remain poorly defined. Here, we established what is to our knowledge the first mammalian model of neutropenia in Shwachman-Diamond syndrome through targeted downregulation of Sbds in hematopoietic stem and progenitor cells expressing the myeloid transcription factor CCAAT/enhancer binding protein α (Cebpa). Sbds deficiency in the myeloid lineage specifically affected myelocytes and their downstream progeny while, unexpectedly, it was well tolerated by rapidly cycling hematopoietic progenitor cells. Molecular insights provided by massive parallel sequencing supported cellular observations of impaired cell cycle exit and formation of secondary granules associated with the defect of myeloid lineage progression in myelocytes. Mechanistically, Sbds deficiency activated the p53 tumor suppressor pathway and induced apoptosis in these cells. Collectively, the data reveal a previously unanticipated, selective dependency of myelocytes and downstream progeny, but not rapidly cycling progenitors, on this ubiquitous ribosome biogenesis protein, thus providing a cellular basis for the understanding of myeloid lineage biased defects in Shwachman-Diamond syndrome.
Collapse
Affiliation(s)
- Noemi A Zambetti
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Eric M J Bindels
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Paulina M H Van Strien
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Marijke G Valkhof
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands Current address: Laboratory for Cell Therapy, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
| | - Maria N Adisty
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Remco M Hoogenboezem
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Mathijs A Sanders
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Johanna M Rommens
- Program in Genetics & Genome Biology, Peter Gilgan Centre for Research and Learning, The Hospital for Sick Children, Department of Molecular Genetics, University of Toronto, ON, Canada
| | - Ivo P Touw
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| | - Marc H G P Raaijmakers
- Department of Hematology, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands
| |
Collapse
|
29
|
Tourlakis ME, Zhang S, Ball HL, Gandhi R, Liu H, Zhong J, Yuan JS, Guidos CJ, Durie PR, Rommens JM. In Vivo Senescence in the Sbds-Deficient Murine Pancreas: Cell-Type Specific Consequences of Translation Insufficiency. PLoS Genet 2015; 11:e1005288. [PMID: 26057580 PMCID: PMC4461263 DOI: 10.1371/journal.pgen.1005288] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 05/18/2015] [Indexed: 01/01/2023] Open
Abstract
Genetic models of ribosome dysfunction show selective organ failure, highlighting a gap in our understanding of cell-type specific responses to translation insufficiency. Translation defects underlie a growing list of inherited and acquired cancer-predisposition syndromes referred to as ribosomopathies. We sought to identify molecular mechanisms underlying organ failure in a recessive ribosomopathy, with particular emphasis on the pancreas, an organ with a high and reiterative requirement for protein synthesis. Biallelic loss of function mutations in SBDS are associated with the ribosomopathy Shwachman-Diamond syndrome, which is typified by pancreatic dysfunction, bone marrow failure, skeletal abnormalities and neurological phenotypes. Targeted disruption of Sbds in the murine pancreas resulted in p53 stabilization early in the postnatal period, specifically in acinar cells. Decreased Myc expression was observed and atrophy of the adult SDS pancreas could be explained by the senescence of acinar cells, characterized by induction of Tgfβ, p15Ink4b and components of the senescence-associated secretory program. This is the first report of senescence, a tumour suppression mechanism, in association with SDS or in response to a ribosomopathy. Genetic ablation of p53 largely resolved digestive enzyme synthesis and acinar compartment hypoplasia, but resulted in decreased cell size, a hallmark of decreased translation capacity. Moreover, p53 ablation resulted in expression of acinar dedifferentiation markers and extensive apoptosis. Our findings indicate a protective role for p53 and senescence in response to Sbds ablation in the pancreas. In contrast to the pancreas, the Tgfβ molecular signature was not detected in fetal bone marrow, liver or brain of mouse models with constitutive Sbds ablation. Nevertheless, as observed with the adult pancreas phenotype, disease phenotypes of embryonic tissues, including marked neuronal cell death due to apoptosis, were determined to be p53-dependent. Our findings therefore point to cell/tissue-specific responses to p53-activation that include distinction between apoptosis and senescence pathways, in the context of translation disruption. Growth of all living things relies on protein synthesis. Failure of components of the complex protein synthesis machinery underlies a growing list of inherited and acquired multi—organ syndromes referred to as ribosomopathies. While ribosomes, the critical working components of the protein synthesis machinery, are required in all cell types to translate the genetic code, only certain organs manifest clinical symptoms in ribosomopathies, indicating specific cell-type features of protein synthesis control. Further, many of these diseases result in cancer despite an inherent deficit in growth. Here we report a range of consequences of protein synthesis insufficiency with loss of a broadly expressed ribosome factor, leading to growth impairment and cell cycle arrest at different stages. Apparent induction of p53-dependent cell death and arrest pathways included apoptosis in the fetal brain and senescence in the mature exocrine pancreas. The senescence, considered a tumour suppression mechanism, was accompanied by the expression of biomarkers associated with early stages of malignant transformation. These findings inform how cancer may initiate when growth is compromised and provide new insights into cell-type specific consequences of protein synthesis insufficiency.
Collapse
Affiliation(s)
- Marina E. Tourlakis
- Program in Genetics & Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Siyi Zhang
- Program in Genetics & Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Heather L. Ball
- Program in Genetics & Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
| | - Rikesh Gandhi
- Program in Genetics & Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
| | - Hongrui Liu
- Program in Genetics & Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Jian Zhong
- Program in Genetics & Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
| | - Julie S. Yuan
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Department of Immunology, University of Toronto, Toronto, Canada
| | - Cynthia J. Guidos
- Program in Developmental and Stem Cell Biology, Research Institute, The Hospital for Sick Children, Department of Immunology, University of Toronto, Toronto, Canada
| | - Peter R. Durie
- Program in Physiology & Experimental Medicine, Research Institute, Division of Gastroenterology & Nutrition, The Hospital for Sick Children, Department of Paediatrics, University of Toronto, Toronto, Canada
| | - Johanna M. Rommens
- Program in Genetics & Genome Biology, Research Institute, The Hospital for Sick Children, Toronto, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
- * E-mail:
| |
Collapse
|
30
|
Yelick PC, Trainor PA. Ribosomopathies: Global process, tissue specific defects. Rare Dis 2015; 3:e1025185. [PMID: 26442198 PMCID: PMC4590025 DOI: 10.1080/21675511.2015.1025185] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2014] [Revised: 02/18/2015] [Accepted: 02/26/2015] [Indexed: 01/01/2023] Open
Abstract
Disruptions in ribosomal biogenesis would be expected to have global and in fact lethal effects on a developing organism. However, mutations in ribosomal protein genes have been shown in to exhibit tissue specific defects. This seemingly contradictory finding - that globally expressed genes thought to play fundamental housekeeping functions can in fact exhibit tissue and cell type specific functions - provides new insight into roles for ribosomes, the protein translational machinery of the cell, in regulating normal development and disease. Furthermore it illustrates the surprisingly dynamic nature of processes regulating cell type specific protein translation. In this review, we discuss our current knowledge of a variety of ribosomal protein mutations associated with human disease, and models to better understand the molecular mechanisms associated with each. We use specific examples to emphasize both the similarities and differences between the effects of various human ribosomal protein mutations. Finally, we discuss areas of future study that are needed to further our understanding of the role of ribosome biogenesis in normal development, and possible approaches that can be used to treat debilitating ribosomopathy diseases.
Collapse
Affiliation(s)
| | - Paul A Trainor
- Stowers Institute ; Kansas City, MO USA ; University of Kansas Medical Center ; Kansas City, KS USA
| |
Collapse
|
31
|
Zhou X, Liao WJ, Liao JM, Liao P, Lu H. Ribosomal proteins: functions beyond the ribosome. J Mol Cell Biol 2015; 7:92-104. [PMID: 25735597 DOI: 10.1093/jmcb/mjv014] [Citation(s) in RCA: 404] [Impact Index Per Article: 44.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 12/05/2014] [Indexed: 01/05/2023] Open
Abstract
Although ribosomal proteins are known for playing an essential role in ribosome assembly and protein translation, their ribosome-independent functions have also been greatly appreciated. Over the past decade, more than a dozen of ribosomal proteins have been found to activate the tumor suppressor p53 pathway in response to ribosomal stress. In addition, these ribosomal proteins are involved in various physiological and pathological processes. This review is composed to overview the current understanding of how ribosomal stress provokes the accumulation of ribosome-free ribosomal proteins, as well as the ribosome-independent functions of ribosomal proteins in tumorigenesis, immune signaling, and development. We also propose the potential of applying these pieces of knowledge to the development of ribosomal stress-based cancer therapeutics.
Collapse
Affiliation(s)
- Xiang Zhou
- Department of Biochemistry & Molecular Biology and Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Wen-Juan Liao
- Department of Biochemistry & Molecular Biology and Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Jun-Ming Liao
- Department of Biochemistry & Molecular Biology and Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Peng Liao
- Department of Biochemistry & Molecular Biology and Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Hua Lu
- Department of Biochemistry & Molecular Biology and Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| |
Collapse
|
32
|
Perobelli S, Alessandrini F, Zoccatelli G, Nicolis E, Beltramello A, Assael BM, Cipolli M. Diffuse alterations in grey and white matter associated with cognitive impairment in Shwachman-Diamond syndrome: evidence from a multimodal approach. NEUROIMAGE-CLINICAL 2015; 7:721-31. [PMID: 25844324 PMCID: PMC4375735 DOI: 10.1016/j.nicl.2015.02.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 02/05/2015] [Accepted: 02/22/2015] [Indexed: 12/01/2022]
Abstract
Shwachman-Diamond syndrome is a rare recessive genetic disease caused by mutations in SBDS gene, at chromosome 7q11. Phenotypically, the syndrome is characterized by exocrine pancreatic insufficiency, bone marrow dysfunction, skeletal dysplasia and variable cognitive impairments. Structural brain abnormalities (smaller head circumference and decreased brain volume) have also been reported. No correlation studies between brain abnormalities and neuropsychological features have yet been performed. In this study we investigate neuroanatomical findings, neurofunctional pathways and cognitive functioning of Shwachman-Diamond syndrome subjects compared with healthy controls. To be eligible for inclusion, participants were required to have known SBDS mutations on both alleles, no history of cranial trauma or any standard contraindication to magnetic resonance imaging. Appropriate tests were used to assess cognitive functions. The static images were acquired on a 3 × 0 T magnetic resonance scanner and blood oxygen level-dependent functional magnetic resonance imaging data were collected both during the execution of the Stroop task and at rest. Diffusion tensor imaging was used to assess brain white matter. The Tract-based Spatial Statistics package and probabilistic tractography were used to characterize white matter pathways. Nine participants (5 males), half of all the subjects aged 9-19 years included in the Italian Shwachman-Diamond Syndrome Registry, were evaluated and compared with nine healthy subjects, matched for sex and age. The patients performed less well than norms and controls on cognitive tasks (p = 0.0002). Overall, cortical thickness was greater in the patients, both in the left (+10%) and in the right (+15%) hemisphere, significantly differently increased in the temporal (left and right, p = 0.04), and right parietal (p = 0.03) lobes and in Brodmann area 44 (p = 0.04) of the right frontal lobe. The greatest increases were observed in the left limbic-anterior cingulate cortex (≥43%, p < 0.0004). Only in Broca's area in the left hemisphere did the patients show a thinner cortical thickness than that of controls (p = 0.01). Diffusion tensor imaging showed large, significant difference increases in both fractional anisotropy (+37%, p < 0.0001) and mean diffusivity (+35%, p < 0.005); the Tract-based Spatial Statistics analysis identified six abnormal clusters of white matter fibres in the fronto-callosal, right fronto-external capsulae, left fronto-parietal, right pontine, temporo-mesial and left anterior-medial-temporal regions. Brain areas activated during the Stroop task and those active during the resting state, are different, fewer and smaller in patients and correlate with worse performance (p = 0.002). Cognitive impairment in Shwachman-Diamond syndrome subjects is associated with diffuse brain anomalies in the grey matter (verbal skills with BA44 and BA20 in the right hemisphere; perceptual skills with BA5, 37, 20, 21, 42 in the left hemisphere) and white matter connectivity (verbal skills with alterations in the fronto-occipital fasciculus and with the inferior-longitudinal fasciculus; perceptual skills with the arcuate fasciculus, limbic and ponto-cerebellar fasciculus; memory skills with the arcuate fasciculus; executive functions with the anterior cingulated and arcuate fasciculus).
Collapse
Key Words
- BA, Brodmann area
- BOLD, blood oxygen level-dependent
- CTA, cortical thickness analysis
- Cognitive impairment
- DTI, diffusion tensor imaging
- Diffusion tensor imaging
- EPI, Echo-planar Imaging
- FA, fractional anisotropy
- FDT, Diffusion Toolbox
- Functional MRI
- GLM, General Linear Model
- ICA, independent component analysis
- MD, mean diffusivity
- PD, parallel diffusivity
- PT, probabilistic tractography
- RD, radial diffusivity
- SDS, Shwachman–Diamond syndrome
- Shwachman–Diamond syndrome
- Structural MRI
- TBSS, Tract-based Spatial Statistics.
- Tract-based Spatial Statistics
- rs-fMRI, resting state fMRI
Collapse
Affiliation(s)
- Sandra Perobelli
- Cystic Fibrosis Centre, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| | - Franco Alessandrini
- Neuroradiology Department, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| | - Giada Zoccatelli
- Neuroradiology Department, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| | - Elena Nicolis
- Laboratory of Molecular Pathology, Laboratory of Clinical Chemistry and Haematology, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| | - Alberto Beltramello
- Neuroradiology Department, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| | - Baroukh M Assael
- Cystic Fibrosis Centre, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| | - Marco Cipolli
- Cystic Fibrosis Centre, Azienda Ospedaliera Universitaria, Piazzale Stefani, 1-37126 Verona, Italy
| |
Collapse
|
33
|
Mercuri A, Cannata E, Perbellini O, Cugno C, Balter R, Zaccaron A, Tridello G, Pizzolo G, De Bortoli M, Krampera M, Cipolli M, Cesaro S. Immunophenotypic analysis of hematopoiesis in patients suffering from Shwachman-Bodian-Diamond Syndrome. Eur J Haematol 2015; 95:308-15. [DOI: 10.1111/ejh.12490] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/11/2014] [Indexed: 01/18/2023]
Affiliation(s)
- Angela Mercuri
- Pediatric Hematology; University of Verona; Verona Italy
| | - Elisa Cannata
- Pediatric Hematology; University of Verona; Verona Italy
| | - Omar Perbellini
- Section of Hematology; Department of Medicine; University of Verona; Verona Italy
| | - Chiara Cugno
- Pediatric Hematology; University of Verona; Verona Italy
| | - Rita Balter
- Pediatric Hematology; University of Verona; Verona Italy
| | - Ada Zaccaron
- Pediatric Hematology; University of Verona; Verona Italy
| | | | - Giovanni Pizzolo
- Section of Hematology; Department of Medicine; University of Verona; Verona Italy
| | | | - Mauro Krampera
- Section of Hematology; Department of Medicine; University of Verona; Verona Italy
| | - Marco Cipolli
- Cystic Fibrosis Center; University of Verona; Verona Italy
| | - Simone Cesaro
- Pediatric Hematology; University of Verona; Verona Italy
| |
Collapse
|
34
|
Ruggero D, Shimamura A. Marrow failure: a window into ribosome biology. Blood 2014; 124:2784-92. [PMID: 25237201 PMCID: PMC4215310 DOI: 10.1182/blood-2014-04-526301] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2014] [Accepted: 05/27/2014] [Indexed: 12/16/2022] Open
Abstract
Diamond-Blackfan anemia, Shwachman-Diamond syndrome, and dyskeratosis congenita are inherited syndromes characterized by marrow failure, congenital anomalies, and cancer predisposition. Genetic and molecular studies have uncovered distinct abnormalities in ribosome biogenesis underlying each of these 3 disorders. How defects in ribosomes, the essential organelles required for protein biosynthesis in all cells, cause tissue-specific abnormalities in human disease remains a question of fundamental scientific and medical importance. Here we review the overlapping and distinct clinical features of these 3 syndromes and discuss current knowledge regarding the ribosomal pathways disrupted in each of these disorders. We also explore the increasing complexity of ribosome biology and how this informs our understanding of developmental biology and human disease.
Collapse
Affiliation(s)
- Davide Ruggero
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA
| | - Akiko Shimamura
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA; Pediatric Hematology/Oncology, Seattle Children's Hospital, Seattle, WA; and Department of Pediatrics, University of Washington, Seattle, WA
| |
Collapse
|
35
|
Trainor PA, Merrill AE. Ribosome biogenesis in skeletal development and the pathogenesis of skeletal disorders. Biochim Biophys Acta Mol Basis Dis 2013; 1842:769-78. [PMID: 24252615 DOI: 10.1016/j.bbadis.2013.11.010] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Revised: 11/05/2013] [Accepted: 11/08/2013] [Indexed: 02/06/2023]
Abstract
The skeleton affords a framework and structural support for vertebrates, while also facilitating movement, protecting vital organs, and providing a reservoir of minerals and cells for immune system and vascular homeostasis. The mechanical and biological functions of the skeleton are inextricably linked to the size and shape of individual bones, the diversity of which is dependent in part upon differential growth and proliferation. Perturbation of bone development, growth and proliferation, can result in congenital skeletal anomalies, which affect approximately 1 in 3000 live births [1]. Ribosome biogenesis is integral to all cell growth and proliferation through its roles in translating mRNAs and building proteins. Disruption of any steps in the process of ribosome biogenesis can lead to congenital disorders termed ribosomopathies. In this review, we discuss the role of ribosome biogenesis in skeletal development and in the pathogenesis of congenital skeletal anomalies. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease.
Collapse
Affiliation(s)
- Paul A Trainor
- Stowers Institute for Medical Research, Kansas City, MO, USA; Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, KS, USA.
| | - Amy E Merrill
- Center for Craniofacial Molecular Biology, Ostrow School of Dentistry, University of Southern California, Los Angeles, CA, USA; Department of Biochemistry and Molecular Biology, Keck School of Medicine, University of Southern California, Los Angeles, CA, USA.
| |
Collapse
|
36
|
Raiser DM, Narla A, Ebert BL. The emerging importance of ribosomal dysfunction in the pathogenesis of hematologic disorders. Leuk Lymphoma 2013; 55:491-500. [DOI: 10.3109/10428194.2013.812786] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
|
37
|
Tulpule A, Kelley JM, Lensch MW, McPherson J, Park IH, Hartung O, Nakamura T, Schlaeger TM, Shimamura A, Daley GQ. Pluripotent stem cell models of Shwachman-Diamond syndrome reveal a common mechanism for pancreatic and hematopoietic dysfunction. Cell Stem Cell 2013; 12:727-36. [PMID: 23602541 DOI: 10.1016/j.stem.2013.04.002] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 02/24/2013] [Accepted: 04/02/2013] [Indexed: 11/18/2022]
Abstract
Shwachman-Diamond syndrome (SDS), a rare autosomal-recessive disorder characterized by exocrine pancreatic insufficiency and hematopoietic dysfunction, is caused by mutations in the Shwachman-Bodian-Diamond syndrome (SBDS) gene. We created human pluripotent stem cell models of SDS through knockdown of SBDS in human embryonic stem cells (hESCs) and generation of induced pluripotent stem cell (iPSC) lines from two patients with SDS. SBDS-deficient hESCs and iPSCs manifest deficits in exocrine pancreatic and hematopoietic differentiation in vitro, enhanced apoptosis, and elevated protease levels in culture supernatants, which could be reversed by restoring SBDS protein expression through transgene rescue or by supplementing culture media with protease inhibitors. Protease-mediated autodigestion provides a mechanistic link between the pancreatic and hematopoietic phenotypes in SDS, highlighting the utility of hESCs and iPSCs in obtaining novel insights into human disease.
Collapse
Affiliation(s)
- Asmin Tulpule
- Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Boston, MA 02115, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
38
|
Sezgin G, Henson AL, Nihrane A, Singh S, Wattenberg M, Alard P, Ellis SR, Liu JM. Impaired growth, hematopoietic colony formation, and ribosome maturation in human cells depleted of Shwachman-Diamond syndrome protein SBDS. Pediatr Blood Cancer 2013; 60:281-6. [PMID: 22997148 DOI: 10.1002/pbc.24300] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Accepted: 08/06/2012] [Indexed: 12/14/2022]
Abstract
BACKGROUND Shwachman-Diamond syndrome (SDS), associated with SBDS mutations, is characterized by pancreatic exocrine dysfunction and marrow failure. Sdo1, the yeast ortholog of SBDS, is implicated in maturation of the 60S ribosomal subunit, with delayed export of 60S-like particles from the nucleoplasm when depleted. Sdo1 is needed for release of the anti-subunit association factor Tif6 from 60S subunits, and Tif6 may not be recycled to the nucleus when Sdo1 is absent. METHODS To clarify the role of SBDS in human ribosome function, TF-1 erythroleukemia and A549 lung carcinoma cells were transfected with vectors expressing RNAi against SBDS. RESULTS Growth and hematopoietic colony forming potential of TF-1 knockdown cells were markedly hindered when compared to controls. To analyze the effect of SBDS on 60S subunit maturation in A549 cells, subunit localization was assessed by transfection with a vector expressing a fusion between human RPL29 and GFP: we found a higher percentage of SBDS-depleted cells with nuclear localization of 60S subunits. Polysome analysis of TF-1 knockdown cells showed a decrease in free 60S and 80S subunits. We also analyzed the levels of eIF6 (human ortholog of Tif6) following near-complete knockdown of SBDS in TF-1 cells and found an approximately 20% increase in the amount of eIF6 associated with the 60S subunit. CONCLUSIONS We conclude that knockdown of SBDS leads to growth inhibition and defects in ribosome maturation, suggesting a role for wild-type SBDS in nuclear export of pre-60S subunits. Furthermore, knockdown of SBDS may interfere with eIF6 recycling.
Collapse
Affiliation(s)
- Gulay Sezgin
- The Feinstein Institute for Medical Research, Manhasset, New York, USA
| | | | | | | | | | | | | | | |
Collapse
|
39
|
Abstract
Shwachman-Diamond syndrome (SDS) is an autosomal-recessive marrow failure syndrome with a predisposition to leukemia. SDS patients harbor biallelic mutations in the SBDS gene, resulting in low levels of SBDS protein. Data from nonhuman models demonstrate that the SBDS protein facilitates the release of eIF6, a factor that prevents ribosome joining. The complete abrogation of Sbds expression in these models results in severe cellular and lethal physiologic abnormalities that differ from the human disease phenotype. Because human SDS cells are characterized by partial rather than complete loss of SBDS expression, we interrogated SDS patient cells for defects in ribosomal assembly. SDS patient cells exhibit altered ribosomal profiles and impaired association of the 40S and 60S subunits. Introduction of a wild-type SBDS cDNA into SDS patient cells corrected the ribosomal association defect, while patient-derived SBDS point mutants only partially improved subunit association. Knockdown of eIF6 expression improved ribosomal subunit association but did not correct the hematopoietic defect of SBDS-deficient cells. In summary, we demonstrate an SBDS-dependent ribosome maturation defect in SDS patient cells. The role of ribosomal subunit joining in marrow failure warrants further investigation.
Collapse
|
40
|
Provost E, Wehner KA, Zhong X, Ashar F, Nguyen E, Green R, Parsons MJ, Leach SD. Ribosomal biogenesis genes play an essential and p53-independent role in zebrafish pancreas development. Development 2012; 139:3232-41. [PMID: 22872088 DOI: 10.1242/dev.077107] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mutations in the human Shwachman-Bodian-Diamond syndrome (SBDS) gene cause defective ribosome assembly and are associated with exocrine pancreatic insufficiency, chronic neutropenia and skeletal defects. However, the mechanism underlying these phenotypes remains unclear. Here we show that knockdown of the zebrafish sbds ortholog fully recapitulates the spectrum of developmental abnormalities observed in the human syndrome, and further implicate impaired proliferation of ptf1a-expressing pancreatic progenitor cells as the basis for the observed pancreatic phenotype. It is thought that diseases of ribosome assembly share a p53-dependent mechanism. However, loss of p53 did not rescue the developmental defects associated with loss of zebrafish sbds. To clarify the molecular mechanisms underlying the observed organogenesis defects, we performed transcriptional profiling to identify candidate downstream mediators of the sbds phenotype. Among transcripts displaying differential expression, functional group analysis revealed marked enrichment of genes related to ribosome biogenesis, rRNA processing and translational initiation. Among these, ribosomal protein L3 (rpl3) and pescadillo (pes) were selected for additional analysis. Similar to knockdown of sbds, knockdown or mutation of either rpl3 or pes resulted in impaired expansion of pancreatic progenitor cells. The pancreatic phenotypes observed in rpl3- and pes-deficient embryos were also independent of p53. Together, these data suggest novel p53-independent roles for ribosomal biogenesis genes in zebrafish pancreas development.
Collapse
Affiliation(s)
- Elayne Provost
- Department of Surgery, Johns Hopkins University, Baltimore, MD 21205, USA
| | | | | | | | | | | | | | | |
Collapse
|
41
|
Tourlakis ME, Zhong J, Gandhi R, Zhang S, Chen L, Durie PR, Rommens JM. Deficiency of Sbds in the mouse pancreas leads to features of Shwachman-Diamond syndrome, with loss of zymogen granules. Gastroenterology 2012; 143:481-92. [PMID: 22510201 DOI: 10.1053/j.gastro.2012.04.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2011] [Revised: 04/01/2012] [Accepted: 04/10/2012] [Indexed: 12/02/2022]
Abstract
BACKGROUND & AIMS Shwachman-Diamond syndrome (SDS) is the second leading cause of hereditary exocrine pancreatic dysfunction. More than 90% of patients with SDS have biallelic loss-of-function mutations in the Shwachman-Bodian Diamond syndrome (SBDS) gene, which encodes a factor involved in ribosome function. We investigated whether mutations in Sbds lead to similar pancreatic defects in mice. METHODS Pancreas-specific knock-out mice were generated using a floxed Sbds allele and bred with mice carrying a null or disease-associated missense Sbds allele. Cre recombinase, regulated by the pancreatic transcription factor 1a promoter, was used to disrupt Sbds specifically in the pancreas. Models were assessed for pancreatic dysfunction and growth impairment. RESULTS Disruption of Sbds in the mouse pancreas was sufficient to recapitulate SDS phenotypes. Pancreata of mice with Sbds mutations had decreased mass, fat infiltration, but general preservation of ductal and endocrine compartments. Pancreatic extracts from mutant mice had defects in formation of the 80S ribosomal complex. The exocrine compartment of mutant mice was hypoplastic and individual acini produced few zymogen granules. The null Sbds allele resulted in an earlier onset of phenotypes as well as endocrine impairment. Mutant mice had reduced serum levels of digestive enzymes and overall growth impairment. CONCLUSIONS We developed a mouse model of SDS with pancreatic phenotypes similar to those of the human disease. This model could be used to investigate organ-specific consequences of Sbds-associated ribosomopathy. Sbds genotypes correlated with phenotypes. Defects developed specifically in the pancreata of mice, reducing growth of mice and production of digestive enzymes. SBDS therefore appears to be required for normal pancreatic development and function.
Collapse
Affiliation(s)
- Marina E Tourlakis
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | | | | | | | | | | | | |
Collapse
|
42
|
Perobelli S, Nicolis E, Assael BM, Cipolli M. Further characterization of Shwachman-Diamond syndrome: Psychological functioning and quality of life in adult and young patients. Am J Med Genet A 2012; 158A:567-73. [DOI: 10.1002/ajmg.a.35211] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Accepted: 11/17/2011] [Indexed: 11/07/2022]
|
43
|
Abstract
Diamond Blackfan anemia (DBA) is a genetic syndrome characterized by red blood cell aplasia in association with developmental abnormalities such as growth retardation, orofacial, hand or limb malformations, urogenital anomalies, and heart defects. The only known cause is heterozygosity for mutations in genes encoding ribosomal proteins. Understanding how defective ribosome biogenesis and function, important for all cells, causes defects in erythropoiesis and tissue-specific phenotypes during development is paramount to the evolution of effective treatment protocols. Here, we discuss how animal models based on mammals, insects, and fish replicate genetic or developmental aspects of DBA and have led to the identification of pathways and candidate molecules that are important in the pathogenesis of the disease. A recurring theme in many of these models suggests that defective ribosome biogenesis induces a p53-dependent cell cycle checkpoint in cells that require high levels of ribosome production and leads to cell type-specific, whole animal phenotypes.
Collapse
Affiliation(s)
- Kelly A McGowan
- Department of Genetics, Stanford University, Stanford, CA 94305, USA.
| | | |
Collapse
|
44
|
Burwick N, Shimamura A, Liu JM. Non-Diamond Blackfan anemia disorders of ribosome function: Shwachman Diamond syndrome and 5q- syndrome. Semin Hematol 2011; 48:136-43. [PMID: 21435510 DOI: 10.1053/j.seminhematol.2011.01.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A number of human disorders, dubbed ribosomopathies, are linked to impaired ribosome biogenesis or function. These include but are not limited to Diamond Blackfan anemia (DBA), Shwachman Diamond syndrome (SDS), and the 5q- myelodysplastic syndrome (MDS). This review focuses on the latter two non-DBA disorders of ribosome function. Both SDS and 5q- syndrome lead to impaired hematopoiesis and a predisposition to leukemia. SDS, due to bi-allelic mutations of the SBDS gene, is a multi-system disorder that also includes bony abnormalities, and pancreatic and neurocognitive dysfunction. SBDS associates with the 60S subunit in human cells and has a role in subunit joining and translational activation in yeast models. In contrast, 5q- syndrome is associated with acquired haplo-insufficiency of RPS14, a component of the small 40S subunit. RPS14 is critical for 40S assembly in yeast models, and depletion of RPS14 in human CD34(+) cells is sufficient to recapitulate the 5q- erythroid defect. Both SDS and the 5q- syndrome represent important models of ribosome function and may inform future treatment strategies for the ribosomopathies.
Collapse
Affiliation(s)
- Nicholas Burwick
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | | | | |
Collapse
|
45
|
Abstract
Shwachman-Diamond syndrome (SDS), a recessive leukemia predisposition disorder characterized by bone marrow failure, exocrine pancreatic insufficiency, skeletal abnormalities and poor growth, is caused by mutations in the highly conserved SBDS gene. Here, we test the hypothesis that defective ribosome biogenesis underlies the pathogenesis of SDS. We create conditional mutants in the essential SBDS ortholog of the ancient eukaryote Dictyostelium discoideum using temperature-sensitive, self-splicing inteins, showing that mutant cells fail to grow at the restrictive temperature because ribosomal subunit joining is markedly impaired. Remarkably, wild type human SBDS complements the growth and ribosome assembly defects in mutant Dictyostelium cells, but disease-associated human SBDS variants are defective. SBDS directly interacts with the GTPase elongation factor-like 1 (EFL1) on nascent 60S subunits in vivo and together they catalyze eviction of the ribosome antiassociation factor eukaryotic initiation factor 6 (eIF6), a prerequisite for the translational activation of ribosomes. Importantly, lymphoblasts from SDS patients harbor a striking defect in ribosomal subunit joining whose magnitude is inversely proportional to the level of SBDS protein. These findings in Dictyostelium and SDS patient cells provide compelling support for the hypothesis that SDS is a ribosomopathy caused by corruption of an essential cytoplasmic step in 60S subunit maturation.
Collapse
|
46
|
Johnson AW, Ellis SR. Of blood, bones, and ribosomes: is Swachman-Diamond syndrome a ribosomopathy? Genes Dev 2011; 25:898-900. [PMID: 21536731 DOI: 10.1101/gad.2053011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Mutations in the human SBDS (Shwachman-Bodian-Diamond syndrome) gene are the most common cause of Shwachman-Diamond syndrome, an inherited bone marrow failure syndrome. In this issue of Genes & Development, Finch and colleagues (pp. 917-929) establish that SBDS functions in ribosome synthesis by promoting the recycling of eukaryotic initiation factor 6 (eIF6) in a GTP-dependent manner. This work supports the idea that a ribosomopathy may underlie this syndrome.
Collapse
Affiliation(s)
- Arlen W Johnson
- Section of Molecular Genetics and Microbiology, The University of Texas at Austin, Texas 78712, USA.
| | | |
Collapse
|
47
|
Mislocalization or low expression of mutated Shwachman–Bodian–Diamond syndrome protein. Int J Hematol 2011; 94:54-62. [DOI: 10.1007/s12185-011-0880-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2010] [Revised: 05/17/2011] [Accepted: 05/19/2011] [Indexed: 11/27/2022]
|
48
|
Leung R, Cuddy K, Wang Y, Rommens J, Glogauer M. Sbds is required for Rac2-mediated monocyte migration and signaling downstream of RANK during osteoclastogenesis. Blood 2011; 117:2044-53. [PMID: 21084708 DOI: 10.1182/blood-2010-05-282574] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Shwachman-Diamond syndrome (SDS) results from mutations in the SBDS gene, characterized by exocrine pancreatic insufficiency and hematologic and skeletal abnormalities. Neutropenia and neutrophil dysfunction are hallmark features of SDS; however, causes for the bone defects are unknown. Dysfunction of bone-resorbing osteoclasts, formed by the fusion of monocytic progenitors derived from the same granulocytic precursors as neutrophils, could be responsible. We report that Sbds is required for in vitro and in vivo osteoclastogenesis (OCG). Sbds-null murine monocytes formed osteoclasts of reduced number and size because of impaired migration and fusion required for OCG. Phenotypically, Sbds-null mice exhibited low-turnover osteoporosis consistent with findings in SDS patients. Western blotting of Rho GTPases that control actin dynamics and migration showed a 5-fold decrease in Rac2, whereas Rac1, Cdc42, and RhoA were unchanged or only mildly reduced. Although migration was rescued on Rac2 supplementation, OCG was not. This was attributed to impaired signaling downstream of receptor activator of nuclear factor-κB (RANK) and reduced expression of the RANK-ligand-dependent fusion receptor DC-STAMP. We conclude that Sbds is required for OCG by regulating monocyte migration via Rac2 and osteoclast differentiation signaling downstream of RANK. Impaired osteoclast formation could disrupt bone homeostasis, resulting in skeletal abnormalities seen in SDS patients.
Collapse
Affiliation(s)
- Roland Leung
- Matrix Dynamics Group, University of Toronto, Toronto, ON, Canada
| | | | | | | | | |
Collapse
|
49
|
Ambekar C, Das B, Yeger H, Dror Y. SBDS-deficiency results in deregulation of reactive oxygen species leading to increased cell death and decreased cell growth. Pediatr Blood Cancer 2010; 55:1138-44. [PMID: 20979173 DOI: 10.1002/pbc.22700] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Shwachman-Diamond syndrome (SDS) is characterized by reduced hematopoietic and exocrine pancreatic cell numbers and a marked propensity for leukemia. Most patients have mutations in the SBDS gene. We previously reported that SBDS-deficient cells overexpress Fas, undergo accelerated spontaneous and Fas-mediated apoptosis and grow slowly. However the mechanism of how SBDS regulates apoptosis remains unknown. Several studies have shown that reactive oxygen species (ROS) regulate cell growth and spontaneous and Fas-mediated cell death. Therefore, we hypothesized that SBDS-deficiency disrupts ROS regulation and subsequently increases sensitivity to Fas stimulation and reduced cell growth. PROCEDURE SBDS was knocked down in HeLa cervical cancer cells and TF-1 myeloid cells using short hairpin RNA. ROS levels were evaluated by oxidation of 2',7'-dichlorodihydrofluorescein diacetate. Apoptosis and cell growth were evaluated with and without antioxidants by annexin V/propidium iodide and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, respectively. RESULTS We found that shRNA mediated SBDS-knockdown resulted in a significant increase in ROS levels compared to control cells. Fas stimulation further increased ROS levels in the SBDS-knockdown HeLa cells more than in the controls. Importantly, balancing ROS levels by antioxidants rescued SBDS-deficient cells from spontaneous and Fas-mediated apoptosis and reduced cell growth. CONCLUSIONS ROS levels are increased in SBDS-deficient cells, which leads to increased apoptosis and decreased cell growth. Increased baseline and Fas-mediated ROS levels in SBDS-deficient cells can enhance the sensitivity to Fas stimulation. By balancing ROS levels, antioxidants can improve cell growth and survival in SBDS-deficient cells.
Collapse
Affiliation(s)
- Chhaya Ambekar
- Cell Biology Program, Research Institute, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | | | | | | |
Collapse
|
50
|
Abstract
BACKGROUND : Because the acinar cells of the exocrine pancreas in patients with Shwachman-Diamond syndrome (SDS) are severely depleted, we hypothesized that a similar deficiency may be present in acinar cells of the parotid gland. PATIENTS AND METHODS : We determined serum pancreatic isoamylase and parotid amylase activities in 16 patients with SDS, 13 healthy controls, and 13 disease controls (cystic fibrosis or fibrosing pancreatitis). Parotid amylase and electrolyte concentrations were measured in stimulated parotid gland secretions. Starch digestion was assessed by breath hydrogen testing in patients with SDS (with and without enzyme supplements) and healthy controls. RESULTS : Serum pancreatic and parotid isoamylase values were lower in the patients with SDS than in the healthy controls (P < 0.0001 and P = 0.0002, respectively). Serum pancreatic isoamylase, but not parotid isoamylase, was significantly lower in the disease controls than in the healthy controls (P < 0.0001 and P = 0.17, respectively). Secreted parotid gland amylase concentration (units per milligram of protein) in patients with SDS was lower than that in the healthy controls (P = 0.04), whereas the disease controls were comparable to the healthy subjects (P = 0.09). Secreted parotid chloride concentration was inversely correlated with amylase concentration in the patients with SDS (P = 0.01), but no correlation was seen in the healthy controls or disease controls. When patients with SDS ingested starch without enzyme supplementation, their breath hydrogen excretion was significantly higher than that in the healthy controls (P = 0.009). Following starch ingestion with enzymes, breath hydrogen in the patients with SDS was lower (P < 0.05) than with no enzyme treatment, and no different from controls (P = 0.37). CONCLUSIONS : Mutations in the SBDS gene cause a generalized functional abnormality of exocrine acinar cells.
Collapse
|