51
|
Wang P, Fiaschi-Taesch NM, Vasavada RC, Scott DK, García-Ocaña A, Stewart AF. Diabetes mellitus--advances and challenges in human β-cell proliferation. Nat Rev Endocrinol 2015; 11:201-12. [PMID: 25687999 DOI: 10.1038/nrendo.2015.9] [Citation(s) in RCA: 157] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The treatment of diabetes mellitus represents one of the greatest medical challenges of our era. Diabetes results from a deficiency or functional impairment of insulin-producing β cells, alone or in combination with insulin resistance. It logically follows that the replacement or regeneration of β cells should reverse the progression of diabetes and, indeed, this seems to be the case in humans and rodents. This concept has prompted attempts in many laboratories to create new human β cells using stem-cell strategies to transdifferentiate or reprogramme non-β cells into β cells or to discover small molecules or other compounds that can induce proliferation of human β cells. This latter approach has shown promise, but has also proven particularly challenging to implement. In this Review, we discuss the physiology of normal human β-cell replication, the molecular mechanisms that regulate the cell cycle in human β cells, the upstream intracellular signalling pathways that connect them to cell surface receptors on β cells, the epigenetic mechanisms that control human β-cell proliferation and unbiased approaches for discovering novel molecules that can drive human β-cell proliferation. Finally, we discuss the potential and challenges of implementing strategies that replace or regenerate β cells.
Collapse
Affiliation(s)
- Peng Wang
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Nathalie M Fiaschi-Taesch
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Rupangi C Vasavada
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Donald K Scott
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Adolfo García-Ocaña
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| | - Andrew F Stewart
- Diabetes, Obesity and Metabolism Institute, Icahn School of Medicine at Mount Sinai, Atran 5, Box 1152, 1 Gustave L. Levy Place, New York, NY 10029, USA
| |
Collapse
|
52
|
Capurso G, Archibugi L, Delle Fave G. Molecular pathogenesis and targeted therapy of sporadic pancreatic neuroendocrine tumors. JOURNAL OF HEPATO-BILIARY-PANCREATIC SCIENCES 2015; 22:594-601. [PMID: 25619712 DOI: 10.1002/jhbp.210] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Accepted: 12/11/2014] [Indexed: 12/11/2022]
Abstract
Over the past few years, knowledge regarding the molecular pathology of sporadic pancreatic neuroendocrine tumors (PNETs) has increased substantially, and a number of targeted agents have been tested in clinical trials in this tumor type. For some of these agents there is a strong biological rationale. Among them, the mammalian target of rapamycin inhibitor Everolimus and the antiangiogenic agent Sunitinib have both been approved for the treatment of PNETs. However, there is lack of knowledge regarding biomarkers able to predict their efficacy, and mechanisms of resistance. Other angiogenesis inhibitors, such as Pazopanib, inhibitors of Src, Hedgehog or of PI3K might all be useful in association or sequence with approved agents. On the other hand, the clinical significance, and potential for treatment of the most common mutations occurring in sporadic PNETs, in the MEN-1 gene and in ATRX and DAXX, remains uncertain. The present paper reviews the main molecular changes occurring in PNETs and how they might be linked with treatment options.
Collapse
Affiliation(s)
- Gabriele Capurso
- Digestive and Liver Disease Unit, Faculty of Medicine and Psychology, Sapienza University of Rome at S. Andrea Hospital, Rome, Italy
| | - Livia Archibugi
- Digestive and Liver Disease Unit, Faculty of Medicine and Psychology, Sapienza University of Rome at S. Andrea Hospital, Rome, Italy
| | - Gianfranco Delle Fave
- Digestive and Liver Disease Unit, Faculty of Medicine and Psychology, Sapienza University of Rome at S. Andrea Hospital, Rome, Italy
| |
Collapse
|
53
|
Kidd M, Modlin IM, Bodei L, Drozdov I. Decoding the Molecular and Mutational Ambiguities of Gastroenteropancreatic Neuroendocrine Neoplasm Pathobiology. Cell Mol Gastroenterol Hepatol 2015; 1:131-153. [PMID: 28210673 PMCID: PMC5301133 DOI: 10.1016/j.jcmgh.2014.12.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 12/19/2014] [Indexed: 02/08/2023]
Abstract
Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN), considered a heterogeneous neoplasia, exhibit ill-defined pathobiology and protean symptomatology and are ubiquitous in location. They are difficult to diagnose, challenging to manage, and outcome depends on cell type, secretory product, histopathologic grading, and organ of origin. A morphologic and molecular genomic review of these lesions highlights tumor characteristics that can be used clinically, such as somatostatin-receptor expression, and confirms features that set them outside the standard neoplasia paradigm. Their unique pathobiology is useful for developing diagnostics using somatostatin-receptor targeted imaging or uptake of radiolabeled amino acids specific to secretory products or metabolism. Therapy has evolved via targeting of protein kinase B signaling or somatostatin receptors with drugs or isotopes (peptide-receptor radiotherapy). With DNA sequencing, rarely identified activating mutations confirm that tumor suppressor genes are relevant. Genomic approaches focusing on cancer-associated genes and signaling pathways likely will remain uninformative. Their uniquely dissimilar molecular profiles mean individual tumors are unlikely to be easily or uniformly targeted by therapeutics currently linked to standard cancer genetic paradigms. The prevalence of menin mutations in pancreatic NEN and P27KIP1 mutations in small intestinal NEN represents initial steps to identifying a regulatory commonality in GEP-NEN. Transcriptional profiling and network-based analyses may define the cellular toolkit. Multianalyte diagnostic tools facilitate more accurate molecular pathologic delineations of NEN for assessing prognosis and identifying strategies for individualized patient treatment. GEP-NEN remain unique, poorly understood entities, and insight into their pathobiology and molecular mechanisms of growth and metastasis will help identify the diagnostic and therapeutic weaknesses of this neoplasia.
Collapse
Key Words
- 5-HT, serotonin, 5-hydroxytryptamine
- Akt, protein kinase B
- BRAF, gene encoding serine/threonine-protein kinase B-Raf
- Blood
- CGH, comparative genomic hybridization
- CREB, cAMP response element-binding protein
- Carcinoid
- CgA, chromogranin A
- D cell, somatostatin
- DAG, diacylglycerol
- EC, enterochromaffin
- ECL, enterochromaffin-like
- EGFR, epidermal growth factor receptor
- ERK, extracellular-signal-regulated kinase
- G cell, gastrin
- GABA, γ-aminobutyric acid
- GEP-NEN, gastroenteropancreatic neuroendocrine neoplasms
- GPCR, G-protein coupled receptor
- Gastroenteropancreatic Neuroendocrine Neoplasms
- IGF-I, insulin-like growth factor-I
- ISG, immature secretory vesicles
- Ki-67
- LOH, loss of heterozygosity
- MAPK, mitogen-activated protein kinase
- MEN-1/MEN1, multiple endocrine neoplasia type 1
- MSI, microsatellite instability
- MTA, metastasis associated-1
- NEN, neuroendocrine neoplasms
- NFκB, nuclear factor κB
- PET, positron emission tomography
- PI3, phosphoinositide-3
- PI3K, phosphoinositide-3 kinase
- PKA, protein kinase A
- PKC, protein kinase C
- PTEN, phosphatase and tensin homolog deleted on chromosome 10
- Proliferation
- SD-208, 2-(5-chloro-2-fluorophenyl)-4-[(4-pyridyl)amino]p-teridine
- SNV, single-nucleotide variant
- SSA, somatostatin analog
- SST, somatostatin
- Somatostatin
- TGF, transforming growth factor
- TGN, trans-Golgi network
- TSC2, tuberous sclerosis complex 2 (tuberin)
- Transcriptome
- VMAT, vesicular monoamine transporters
- X/A-like cells, ghrelin
- cAMP, adenosine 3′,5′-cyclic monophosphate
- mTOR, mammalian target of rapamycin
- miR/miRNA, micro-RNA
Collapse
Affiliation(s)
| | - Irvin M. Modlin
- Correspondence Address correspondence to: Irvin M. Modlin, MD, PhD, The Gnostic Consortium, Wren Laboratories, 35 NE Industrial Road, Branford, Connecticut, 06405.
| | | | | |
Collapse
|
54
|
De Jesus DF, Kulkarni RN. Epigenetic modifiers of islet function and mass. Trends Endocrinol Metab 2014; 25:628-36. [PMID: 25246382 DOI: 10.1016/j.tem.2014.08.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 08/22/2014] [Accepted: 08/25/2014] [Indexed: 01/28/2023]
Abstract
Type 2 diabetes (T2D) is associated with insulin resistance in target tissues including the β-cell, leading to significant β-cell loss and secretory dysfunction. T2D is also associated with aging, and the underlying mechanisms that increase susceptibility of an individual to develop the disease implicate epigenetics: interactions between susceptible loci and the environment. In this review, we discuss the effects of aging on β-cell function and adaptation, besides the significance of mitochondria in islet bioenergetics and epigenome. We highlight three important modulators of the islet epigenome, namely: metabolites, hormones, and the nutritional state. Unraveling the signaling pathways that regulate the islet epigenome during aging will help to better understand the development of disease progression and to design novel therapies for diabetes prevention.
Collapse
Affiliation(s)
- Dario F De Jesus
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA; Graduate Program in Areas of Basic and Applied Biology (GABBA), Abdel Salazar Biomedical Sciences Institute, University of Porto, 5000 Porto, Portugal
| | - Rohit N Kulkarni
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, MA 02215, USA; Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
55
|
García-Ocaña A, Stewart AF. "RAS"ling β cells to proliferate for diabetes: why do we need MEN? J Clin Invest 2014; 124:3698-700. [PMID: 25133422 DOI: 10.1172/jci77764] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Adult human pancreatic β cells are refractory to current therapeutic approaches to enhance proliferation. This reluctance to expand is problematic, especially for people with diabetes who lack sufficient numbers of functional insulin-producing β cells and could therefore benefit from therapies for β cell expansion. In this issue of the JCI, Chamberlain et al. describe a surprising series of observations that involve two downstream arms of the RAS signaling pathway, MAPK and RASSF proteins, which also involve the tumor suppressor menin. The findings of this study may help explain the difficulty of inducing β cell proliferation and may provide leads for therapeutic expansion of human β cells.
Collapse
|