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Goldsmith J, Ordureau A, Wade Harper J, Holzbaur EL. Brain-derived autophagosome profiling reveals the engulfment of nucleoid-enriched mitochondrial fragments by basal autophagy in neurons. Neuron 2024; 112:520. [PMID: 38330901 PMCID: PMC10935664 DOI: 10.1016/j.neuron.2024.01.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2024]
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2
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Goldsmith J, Holzbaur ELF. Proteomic profiling shows mitochondrial nucleoids are autophagy cargo in neurons: implications for neuron maintenance and neurodegenerative disease. Autophagy 2022; 18:2003-2005. [PMID: 35343362 PMCID: PMC9450978 DOI: 10.1080/15548627.2022.2056865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 03/16/2022] [Accepted: 03/18/2022] [Indexed: 11/02/2022] Open
Abstract
Neurons depend on macroautophagy/autophagy to maintain cellular homeostasis, and loss of autophagy leads to neurodegeneration. To better understand the role of basal autophagy in neurons, we enriched autophagic vesicles from healthy adult mouse brain and performed mass spectrometry to identify cargos cleared by autophagy. We found that synaptic and mitochondrial proteins comprise nearly half of the unique AV cargos identified in brain. Similarly, synaptic and mitochondrial proteins are major cargos for basal autophagy in neurons. Strikingly, we noted a specific enrichment of mitochondrial nucleoids within neuronal autophagosomes, which occurs through a mechanism distinct from damage-associated mitophagy. Here, we discuss the implications of these findings for our understanding of homeostatic mechanisms in neurons and how the age-dependent decline of autophagy in neurons may contribute to the onset or progression of neurodegenerative disease.
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Affiliation(s)
- Juliet Goldsmith
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Erika L. F. Holzbaur
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
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3
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Goldsmith J, Ordureau A, Harper JW, Holzbaur ELF. Brain-derived autophagosome profiling reveals the engulfment of nucleoid-enriched mitochondrial fragments by basal autophagy in neurons. Neuron 2022; 110:967-976.e8. [PMID: 35051374 PMCID: PMC8930448 DOI: 10.1016/j.neuron.2021.12.029] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 10/18/2021] [Accepted: 12/16/2021] [Indexed: 12/20/2022]
Abstract
Neurons depend on autophagy to maintain cellular homeostasis, and defects in autophagy are pathological hallmarks of neurodegenerative disease. To probe the role of basal autophagy in the maintenance of neuronal health, we isolated autophagic vesicles from mouse brain tissue and used proteomics to identify the major cargos engulfed within autophagosomes, validating our findings in rodent primary and human iPSC-derived neurons. Mitochondrial proteins were identified as a major cargo in the absence of mitophagy adaptors such as OPTN. We found that nucleoid-associated proteins are enriched compared with other mitochondrial components. In the axon, autophagic engulfment of nucleoid-enriched mitochondrial fragments requires the mitochondrial fission machinery Drp1. We proposed that localized Drp1-dependent fission of nucleoid-enriched fragments in proximity to the sites of autophagosome biogenesis enhances their capture. The resulting efficient autophagic turnover of nucleoids may prevent accumulation of mitochondrial DNA in the neuron, thus mitigating activation of proinflammatory pathways that contribute to neurodegeneration.
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Affiliation(s)
- Juliet Goldsmith
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Alban Ordureau
- Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - J Wade Harper
- Department of Cell Biology, Blavatnik Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Erika L F Holzbaur
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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4
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Rudnick JA, Monkkonen T, Mar FA, Barnes JM, Starobinets H, Goldsmith J, Roy S, Bustamante Eguiguren S, Weaver VM, Debnath J. Autophagy in stromal fibroblasts promotes tumor desmoplasia and mammary tumorigenesis. Genes Dev 2021; 35:963-975. [PMID: 34168038 PMCID: PMC8247603 DOI: 10.1101/gad.345629.120] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 05/24/2021] [Indexed: 01/11/2023]
Abstract
In this study, Rudnick et al. use mouse mammary cancer models and syngeneic transplantation assays to demonstrate that genetic ablation of stromal fibroblast autophagy significantly impedes fundamental elements of the stromal desmoplastic response, including collagen and proinflammatory cytokine secretion, extracellular matrix stiffening, and neoangiogenesis. Their findings suggest the efficacy of autophagy inhibition is shaped by the ability of host stromal fibroblast autophagy to support tumor desmoplasia. Autophagy inhibitors are currently being evaluated in clinical trials for the treatment of diverse cancers, largely due to their ability to impede tumor cell survival and metabolic adaptation. More recently, there is growing interest in whether and how modulating autophagy in the host stroma influences tumorigenesis. Fibroblasts play prominent roles in cancer initiation and progression, including depositing type 1 collagen and other extracellular matrix (ECM) components, thereby stiffening the surrounding tissue to enhance tumor cell proliferation and survival, as well as secreting cytokines that modulate angiogenesis and the immune microenvironment. This constellation of phenotypes, pathologically termed desmoplasia, heralds poor prognosis and reduces patient survival. Using mouse mammary cancer models and syngeneic transplantation assays, we demonstrate that genetic ablation of stromal fibroblast autophagy significantly impedes fundamental elements of the stromal desmoplastic response, including collagen and proinflammatory cytokine secretion, extracellular matrix stiffening, and neoangiogenesis. As a result, autophagy in stromal fibroblasts is required for mammary tumor growth in vivo, even when the cancer cells themselves remain autophagy-competent . We propose the efficacy of autophagy inhibition is shaped by this ability of host stromal fibroblast autophagy to support tumor desmoplasia.
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Affiliation(s)
- Jenny A Rudnick
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA
| | - Teresa Monkkonen
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA
| | - Florie A Mar
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA.,Biomedical Sciences Graduate Program, University of California at San Francisco, San Francisco, California 94143, USA
| | - James M Barnes
- Department of Surgery, Center for Bioengineering and Tissue Regeneration, University of California at San Francisco, San Francisco, California 94143, USA
| | - Hanna Starobinets
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA.,Biomedical Sciences Graduate Program, University of California at San Francisco, San Francisco, California 94143, USA
| | - Juliet Goldsmith
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA.,Biomedical Sciences Graduate Program, University of California at San Francisco, San Francisco, California 94143, USA
| | - Srirupa Roy
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA
| | - Sofía Bustamante Eguiguren
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA
| | - Valerie M Weaver
- Department of Surgery, Center for Bioengineering and Tissue Regeneration, University of California at San Francisco, San Francisco, California 94143, USA.,Department of Anatomy, University of California at San Francisco, San Francisco, California 94143, USA.,Department of Bioengineering and Therapeutic Sciences, University of California at San Francisco, San Francisco, California 94143, USA
| | - Jayanta Debnath
- Department of Pathology, Helen Diller Family Comprehensive Cancer Center, University of California at San Francisco, San Francisco, California 94143, USA
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5
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Kaur J, Goldsmith J, Tankka A, Bustamante Eguiguren S, Gimenez AA, Vick L, Debnath J, Vlahakis A. Atg32-dependent mitophagy sustains spermidine and nitric oxide required for heat-stress tolerance in Saccharomycescerevisiae. J Cell Sci 2021; 134:jcs253781. [PMID: 34096604 PMCID: PMC8214763 DOI: 10.1242/jcs.253781] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 05/06/2021] [Indexed: 11/20/2022] Open
Abstract
In Saccharomyces cerevisiae, the selective autophagic degradation of mitochondria, termed mitophagy, is critically regulated by the adapter protein Atg32. Despite our knowledge about the molecular mechanisms by which Atg32 controls mitophagy, its physiological roles in yeast survival and fitness remains less clear. Here, we demonstrate a requirement for Atg32 in promoting spermidine production during respiratory growth and heat-induced mitochondrial stress. During respiratory growth, mitophagy-deficient yeast exhibit profound heat-stress induced defects in growth and viability due to impaired biosynthesis of spermidine and its biosynthetic precursor S-adenosyl methionine. Moreover, spermidine production is crucial for the induction of cytoprotective nitric oxide (NO) during heat stress. Hence, the re-addition of spermidine to Atg32 mutant yeast is sufficient to both enhance NO production and restore respiratory growth during heat stress. Our findings uncover a previously unrecognized physiological role for yeast mitophagy in spermidine metabolism and illuminate new interconnections between mitophagy, polyamine biosynthesis and NO signaling.
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6
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Boecker CA, Goldsmith J, Dou D, Cajka GG, Holzbaur ELF. Increased LRRK2 kinase activity alters neuronal autophagy by disrupting the axonal transport of autophagosomes. Curr Biol 2021; 31:2140-2154.e6. [PMID: 33765413 PMCID: PMC8154747 DOI: 10.1016/j.cub.2021.02.061] [Citation(s) in RCA: 78] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 12/14/2020] [Accepted: 02/26/2021] [Indexed: 10/21/2022]
Abstract
Parkinson's disease-causing mutations in the leucine-rich repeat kinase 2 (LRRK2) gene hyperactivate LRRK2 kinase activity and cause increased phosphorylation of Rab GTPases, important regulators of intracellular trafficking. We found that the most common LRRK2 mutation, LRRK2-G2019S, dramatically reduces the processivity of autophagosome transport in neurons in a kinase-dependent manner. This effect was consistent across an overexpression model, neurons from a G2019S knockin mouse, and human induced pluripotent stem cell (iPSC)-derived neurons gene edited to express the G2019S mutation, and the effect was reversed by genetic or pharmacological inhibition of LRRK2. Furthermore, LRRK2 hyperactivation induced by overexpression of Rab29, a known activator of LRRK2 kinase, disrupted autophagosome transport to a similar extent. Mechanistically, we found that hyperactive LRRK2 recruits the motor adaptor JNK-interacting protein 4 (JIP4) to the autophagosomal membrane, inducing abnormal activation of kinesin that we propose leads to an unproductive tug of war between anterograde and retrograde motors. Disruption of autophagosome transport correlated with a significant defect in autophagosome acidification, suggesting that the observed transport deficit impairs effective degradation of autophagosomal cargo in neurons. Our results robustly link increased LRRK2 kinase activity to defects in autophagosome transport and maturation, further implicating defective autophagy in the pathogenesis of Parkinson's disease.
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Affiliation(s)
- C Alexander Boecker
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Juliet Goldsmith
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Dan Dou
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Gregory G Cajka
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Erika L F Holzbaur
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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7
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Cason SE, Carman PJ, Van Duyne C, Goldsmith J, Dominguez R, Holzbaur ELF. Sequential dynein effectors regulate axonal autophagosome motility in a maturation-dependent pathway. J Cell Biol 2021; 220:212171. [PMID: 34014261 PMCID: PMC8142281 DOI: 10.1083/jcb.202010179] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 03/31/2021] [Accepted: 04/28/2021] [Indexed: 12/14/2022] Open
Abstract
Autophagy is a degradative pathway required to maintain homeostasis. Neuronal autophagosomes form constitutively at the axon terminal and mature via lysosomal fusion during dynein-mediated transport to the soma. How the dynein–autophagosome interaction is regulated is unknown. Here, we identify multiple dynein effectors on autophagosomes as they transit along the axons of primary neurons. In the distal axon, JIP1 initiates autophagosomal transport. Autophagosomes in the mid-axon require HAP1 and Huntingtin. We find that HAP1 is a dynein activator, binding the dynein–dynactin complex via canonical and noncanonical interactions. JIP3 is on most axonal autophagosomes, but specifically regulates the transport of mature autolysosomes. Inhibiting autophagosomal transport disrupts maturation, and inhibiting autophagosomal maturation perturbs the association and function of dynein effectors; thus, maturation and transport are tightly linked. These results reveal a novel maturation-based dynein effector handoff on neuronal autophagosomes that is key to motility, cargo degradation, and the maintenance of axonal health.
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Affiliation(s)
- Sydney E Cason
- Department of Physiology, University of Pennsylvania, Philadelphia, PA.,Neuroscience Graduate Group, University of Pennsylvania, Philadelphia, PA
| | - Peter J Carman
- Department of Physiology, University of Pennsylvania, Philadelphia, PA.,Biochemistry and Molecular Biophysics Graduate Group, University of Pennsylvania, Philadelphia, PA
| | - Claire Van Duyne
- Department of Physiology, University of Pennsylvania, Philadelphia, PA.,Vagelos Scholars Program, University of Pennsylvania, Philadelphia, PA
| | - Juliet Goldsmith
- Department of Physiology, University of Pennsylvania, Philadelphia, PA
| | - Roberto Dominguez
- Department of Physiology, University of Pennsylvania, Philadelphia, PA.,Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, PA
| | - Erika L F Holzbaur
- Department of Physiology, University of Pennsylvania, Philadelphia, PA.,Pennsylvania Muscle Institute, University of Pennsylvania, Philadelphia, PA
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8
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Goldsmith J, Marsh T, Asthana S, Leidal AM, Suresh D, Olshen A, Debnath J. Ribosome profiling reveals a functional role for autophagy in mRNA translational control. Commun Biol 2020; 3:388. [PMID: 32681145 PMCID: PMC7367890 DOI: 10.1038/s42003-020-1090-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 06/19/2020] [Indexed: 01/09/2023] Open
Abstract
Autophagy promotes protein degradation, and therefore has been proposed to maintain amino acid pools to sustain protein synthesis during metabolic stress. To date, how autophagy influences the protein synthesis landscape in mammalian cells remains unclear. Here, we utilize ribosome profiling to delineate the effects of genetic ablation of the autophagy regulator, ATG12, on translational control. In mammalian cells, genetic loss of autophagy does not impact global rates of cap dependent translation, even under starvation conditions. Instead, autophagy supports the translation of a subset of mRNAs enriched for cell cycle control and DNA damage repair. In particular, we demonstrate that autophagy enables the translation of the DNA damage repair protein BRCA2, which is functionally required to attenuate DNA damage and promote cell survival in response to PARP inhibition. Overall, our findings illuminate that autophagy impacts protein translation and shapes the protein landscape.
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Affiliation(s)
- Juliet Goldsmith
- Department of Pathology, University of California San Francisco, San Francisco, CA, 94143, USA
| | - Timothy Marsh
- Department of Pathology, University of California San Francisco, San Francisco, CA, 94143, USA
| | - Saurabh Asthana
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, 94158, USA
- Helen Diller Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Andrew M Leidal
- Department of Pathology, University of California San Francisco, San Francisco, CA, 94143, USA
| | - Deepthisri Suresh
- Department of Pathology, University of California San Francisco, San Francisco, CA, 94143, USA
| | - Adam Olshen
- Department of Epidemiology and Biostatistics, University of California San Francisco, San Francisco, CA, 94158, USA
- Helen Diller Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, 94158, USA
| | - Jayanta Debnath
- Department of Pathology, University of California San Francisco, San Francisco, CA, 94143, USA.
- Helen Diller Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, 94158, USA.
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9
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Goldsmith J, Holzbaur ELF. Presynaptic Homeostatic Plasticity Staves off Neurodegenerative Pathophysiology up to a Tipping Point. Neuron 2020; 107:6-8. [PMID: 32645308 DOI: 10.1016/j.neuron.2020.06.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this issue of Neuron, Orr et al. (2020) identify an evolutionarily conserved mechanism of presynaptic homeostatic plasticity induced by ALS-like motor neuron degeneration, which maintains excitatory potentials until a threshold of synaptic loss is reached. Past this tipping point, disease onset progresses rapidly.
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Affiliation(s)
- Juliet Goldsmith
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Erika L F Holzbaur
- Department of Physiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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10
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Leidal AM, Huang HH, Marsh T, Solvik T, Zhang D, Ye J, Kai F, Goldsmith J, Liu JY, Huang YH, Monkkonen T, Vlahakis A, Huang EJ, Goodarzi H, Yu L, Wiita AP, Debnath J. The LC3-conjugation machinery specifies the loading of RNA-binding proteins into extracellular vesicles. Nat Cell Biol 2020; 22:187-199. [PMID: 31932738 PMCID: PMC7007875 DOI: 10.1038/s41556-019-0450-y] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Accepted: 12/03/2019] [Indexed: 12/11/2022]
Abstract
Traditionally viewed as an autodigestive pathway, autophagy also facilitates cellular secretion; however, the mechanisms underlying these processes remain unclear. Here, we demonstrate that components of the autophagy machinery specify secretion within extracellular vesicles (EVs). Using a proximity-dependent biotinylation proteomics strategy, we identify 200 putative targets of LC3-dependent secretion. This secretome consists of a highly interconnected network enriched in RNA-binding proteins (RBPs) and EV cargoes. Proteomic and RNA profiling of EVs identifies diverse RBPs and small non-coding RNAs requiring the LC3-conjugation machinery for packaging and secretion. Focusing on two RBPs, heterogeneous nuclear ribonucleoprotein K (HNRNPK) and scaffold-attachment factor B (SAFB), we demonstrate that these proteins interact with LC3 and are secreted within EVs enriched with lipidated LC3. Furthermore, their secretion requires the LC3-conjugation machinery, neutral sphingomyelinase 2 (nSMase2) and LC3-dependent recruitment of factor associated with nSMase2 activity (FAN). Hence, the LC3-conjugation pathway controls EV cargo loading and secretion.
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Affiliation(s)
- Andrew M Leidal
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Hector H Huang
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Timothy Marsh
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Tina Solvik
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Dachuan Zhang
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Jordan Ye
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - FuiBoon Kai
- Department of Surgery, University of California San Francisco, San Francisco, CA, USA
| | - Juliet Goldsmith
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Jennifer Y Liu
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Yu-Hsin Huang
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Teresa Monkkonen
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Ariadne Vlahakis
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Eric J Huang
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA
| | - Hani Goodarzi
- Department of Biochemistry and Biophysics, Department of Urology, and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA, USA
| | - Li Yu
- State Key Laboratory of Membrane Biology, Tsinghua University-Peking University Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Arun P Wiita
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, USA.
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11
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Zheng Y, Sethi R, Mangala LS, Taylor C, Goldsmith J, Wang M, Masuda K, Karaminejadranjbar M, Mannion D, Miranda F, Herrero-Gonzalez S, Hellner K, Chen F, Alsaadi A, Albukhari A, Fotso DC, Yau C, Jiang D, Pradeep S, Rodriguez-Aguayo C, Lopez-Berestein G, Knapp S, Gray NS, Campo L, Myers KA, Dhar S, Ferguson D, Bast RC, Sood AK, von Delft F, Ahmed AA. Tuning microtubule dynamics to enhance cancer therapy by modulating FER-mediated CRMP2 phosphorylation. Nat Commun 2018; 9:476. [PMID: 29396402 PMCID: PMC5797184 DOI: 10.1038/s41467-017-02811-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 12/27/2017] [Indexed: 12/13/2022] Open
Abstract
Though used widely in cancer therapy, paclitaxel only elicits a response in a fraction of patients. A strong determinant of paclitaxel tumor response is the state of microtubule dynamic instability. However, whether the manipulation of this physiological process can be controlled to enhance paclitaxel response has not been tested. Here, we show a previously unrecognized role of the microtubule-associated protein CRMP2 in inducing microtubule bundling through its carboxy terminus. This activity is significantly decreased when the FER tyrosine kinase phosphorylates CRMP2 at Y479 and Y499. The crystal structures of wild-type CRMP2 and CRMP2-Y479E reveal how mimicking phosphorylation prevents tetramerization of CRMP2. Depletion of FER or reducing its catalytic activity using sub-therapeutic doses of inhibitors increases paclitaxel-induced microtubule stability and cytotoxicity in ovarian cancer cells and in vivo. This work provides a rationale for inhibiting FER-mediated CRMP2 phosphorylation to enhance paclitaxel on-target activity for cancer therapy. Some anticancer drugs target cell microtubules inhibiting mitosis and cell division. Here, the authors show that CRMP2 induces microtubule bundling and that this activity is regulated by the FER kinase, thus providing a rationale for targeting FER in combination with microtubule-targeting drugs.
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Affiliation(s)
- Yiyan Zheng
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Ritika Sethi
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK
| | - Lingegowda S Mangala
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.,Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Charlotte Taylor
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Juliet Goldsmith
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Ming Wang
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Kenta Masuda
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Mohammad Karaminejadranjbar
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - David Mannion
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Fabrizio Miranda
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Sandra Herrero-Gonzalez
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Karin Hellner
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Fiona Chen
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Abdulkhaliq Alsaadi
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Ashwag Albukhari
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK.,Biochemistry Department, Faculty of Science, King Abdulaziz University, Jeddah, 21551, Saudi Arabia
| | - Donatien Chedom Fotso
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK.,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - Christopher Yau
- Wellcome Trust Centre for Human Genetics and NIHR Biomedical Research Centre, Roosevelt Drive, Oxford, OX3 7BN, UK.,Department of Statistics, 1 South Parks Road, Oxford, OX1 3TG, UK
| | - Dahai Jiang
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.,Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Sunila Pradeep
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Cristian Rodriguez-Aguayo
- Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.,Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Gabriel Lopez-Berestein
- Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.,Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Stefan Knapp
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK.,Goethe-University Frankfurt, Institute for Pharmaceutical Chemistry and Buchmann Institute for Life Sciences, Riedberg Campus, Frankfurt am Main, 60438, Germany
| | - Nathanael S Gray
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, 02115, USA.,Department of Cancer Biology, Dana-Farber Cancer Institute, Boston, MA, 02215, USA
| | - Leticia Campo
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
| | - Kevin A Myers
- Department of Oncology, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, UK
| | - Sunanda Dhar
- Department of Histopathology, Oxford University Hospitals, Oxford, OX3 9DU, UK
| | - David Ferguson
- Nuffield Division of Clinical Laboratory Sciences, Radcliffe Department of Medicine University of Oxford, Oxford University Hospitals, Oxford, OX3 9DU, UK
| | - Robert C Bast
- Department of Experimental Therapeutics, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Anil K Sood
- Department of Gynecologic Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA.,Center for RNAi and Non-Coding RNA, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX, 77030, USA
| | - Frank von Delft
- Structural Genomics Consortium, Nuffield Department of Medicine, University of Oxford, Old Road Campus Research Building, Oxford, OX3 7DQ, UK.,Diamond Light Source Ltd, Harwell Science and Innovation Campus, Didcot, OX11 0QX, UK.,Department of Biochemistry, University of Johannesburg, Auckland Park, 2006, South Africa
| | - Ahmed Ashour Ahmed
- Ovarian Cancer Cell Laboratory, Weatherall Institute of Molecular Medicine, University of Oxford, Headington, Oxford, OX3 9DS, UK. .,Nuffield Department of Obstetrics & Gynaecology, University of Oxford, Women's Centre, John Radcliffe Hospital, Oxford, OX3 9DU, UK.
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12
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Starobinets H, Ye J, Broz M, Barry K, Goldsmith J, Marsh T, Rostker F, Krummel M, Debnath J. Antitumor adaptive immunity remains intact following inhibition of autophagy and antimalarial treatment. J Clin Invest 2016; 126:4417-4429. [PMID: 27775547 DOI: 10.1172/jci85705] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 09/15/2016] [Indexed: 01/05/2023] Open
Abstract
The rising success of cancer immunotherapy has produced immense interest in defining the clinical contexts that may benefit from this therapeutic approach. To this end, there is a need to ascertain how the therapeutic modulation of intrinsic cancer cell programs influences the anticancer immune response. For example, the role of autophagy as a tumor cell survival and metabolic fitness pathway is being therapeutically targeted in ongoing clinical trials that combine cancer therapies with antimalarial drugs for the treatment of a broad spectrum of cancers, many of which will likely benefit from immunotherapy. However, our current understanding of the interplay between autophagy and the immune response remains incomplete. Here, we have evaluated how autophagy inhibition impacts the antitumor immune response in immune-competent mouse models of melanoma and mammary cancer. We observed equivalent levels of T cell infiltration and function within autophagy-competent and -deficient tumors, even upon treatment with the anthracycline chemotherapeutic doxorubicin. Similarly, we found equivalent T cell responses upon systemic treatment of tumor-bearing mice with antimalarial drugs. Our findings demonstrate that antitumor adaptive immunity is not adversely impaired by autophagy inhibition in these models, allowing for the future possibility of combining autophagy inhibitors with immunotherapy in certain clinical contexts.
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13
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Kenific CM, Stehbens SJ, Goldsmith J, Leidal AM, Faure N, Ye J, Wittmann T, Debnath J. NBR1 enables autophagy-dependent focal adhesion turnover. J Cell Biol 2016; 212:577-90. [PMID: 26903539 PMCID: PMC4772495 DOI: 10.1083/jcb.201503075] [Citation(s) in RCA: 113] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 01/19/2016] [Indexed: 12/21/2022] Open
Abstract
The selective autophagy cargo receptor NBR1 enhances the disassembly of cell-matrix focal adhesions during cell migration. Autophagy is a catabolic pathway involving the sequestration of cellular contents into a double-membrane vesicle, the autophagosome. Although recent studies have demonstrated that autophagy supports cell migration, the underlying mechanisms remain unknown. Using live-cell imaging, we uncover that autophagy promotes optimal migratory rate and facilitates the dynamic assembly and disassembly of cell-matrix focal adhesions (FAs), which is essential for efficient motility. Additionally, our studies reveal that autophagosomes associate with FAs primarily during disassembly, suggesting autophagy locally facilitates the destabilization of cell-matrix contact sites. Furthermore, we identify the selective autophagy cargo receptor neighbor of BRCA1 (NBR1) as a key mediator of autophagy-dependent FA remodeling. NBR1 depletion impairs FA turnover and decreases targeting of autophagosomes to FAs, whereas ectopic expression of autophagy-competent, but not autophagy-defective, NBR1 enhances FA disassembly and reduces FA lifetime during migration. Our findings provide mechanistic insight into how autophagy promotes migration by revealing a requirement for NBR1-mediated selective autophagy in enabling FA disassembly in motile cells.
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Affiliation(s)
- Candia M Kenific
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143 Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Samantha J Stehbens
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143
| | - Juliet Goldsmith
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143 Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Andrew M Leidal
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Nathalie Faure
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Jordan Ye
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
| | - Torsten Wittmann
- Department of Cell and Tissue Biology, University of California, San Francisco, San Francisco, CA 94143
| | - Jayanta Debnath
- Department of Pathology and Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94143
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14
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Abstract
BACKGROUND Residency recruitment is a high-stakes activity for all participants, yet there is limited information about how applicants choose among programs. OBJECTIVE This study evaluated the importance applicants place on various residency program attributes; whether applicant priorities vary by sex, race/ethnicity, or specialty choice; and whether the importance of these factors changes over time. METHODS Highly ranked applicants to residency programs at 2 academic medical centers were surveyed annually from 2004 to 2012 regarding the importance of 26 characteristics in selecting a program. Mean ratings of importance for each factor were analyzed to assess priority for the overall applicant group, and whether priorities differed for subgroups (by sex, race/ethnicity, and specialty). RESULTS Of 9669 applicants surveyed, 6285 (65%) responded. The 5 factors with highest rating of importance (overall and across all subgroups) were the program's ability to prepare residents for future training or position, resident esprit de corps, faculty availability and involvement in teaching, depth and breadth of faculty, and variety of patients and clinical resources. Small but significant differences in the ratings of some factors by sex and/or specialty group were identified. Institution-level characteristics, such as call rooms, salary, and benefits, were relatively unimportant. Applicant priorities were stable over the 9-year study period. CONCLUSIONS Highly ranked applicants to competitive residency programs value educational aspects of the program most highly, along with resident morale. Top factors were consistent across subgroups and over the 9 years of the study. These findings have implications for resident recruitment strategies.
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15
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Townley HE, Zheng Y, Goldsmith J, Zheng YY, Stratford MRL, Dobson PJ, Ahmed AA. A novel biosensor for quantitative monitoring of on-target activity of paclitaxel. Nanoscale 2015; 7:1127-1135. [PMID: 25483994 DOI: 10.1039/c4nr01105h] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
This study describes a system for quantifying paclitaxel activity using the C-terminus of α-tubulin as a biomarker. Following stabilization of microtubules with paclitaxel, a specific detyrosination reaction occurs at the C-terminus of α-tubulin which could be used to assess efficacy. A fluorescence resonance energy transfer (FRET) based biosensor was synthesized comprising a short peptide that corresponded to the C-terminus of α-tubulin, a fluorophore (Abz), and a quencher (Dnp). The fluorophore added to the end of the peptide can be released upon enzymatic detyrosination. In addition, a single fluorophore-tagged peptide was also conjugated to mesoporous silica nanoparticles to examine the feasibility of combining the drug with the peptide biomarker. As a proof of concept, we found that the degree of peptide cleavage, and therefore enzymatic activity, was directly correlated with exogenous bovine carboxypeptidase (CPA) an enzyme that mimics endogenous detyrosination. In addition, we show that cell lysates obtained from paclitaxel-treated cancer cells competed with exogenous CPA for biosensor cleavage in a paclitaxel dose-dependent manner. Our work provides strong evidence for the feasibility of combining paclitaxel with a novel biosensor in a multi-load nanoparticle.
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Affiliation(s)
- H E Townley
- Department of Engineering Sciences, Parks Road, Oxford, OX1 3PJ, UK.
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16
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Sleath B, Blalock S, Muir K, Carpenter D, Giangiacomo A, Lawrence S, Slota C, Hartnett M, Goldsmith J, Robin A. Self-efficacy, outcome expectations, depressive symptoms, and glaucoma medication adherence. Res Social Adm Pharm 2014. [DOI: 10.1016/j.sapharm.2014.07.133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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17
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Abstract
Functional principal components (FPC) analysis is widely used to decompose and express functional observations. Curve estimates implicitly condition on basis functions and other quantities derived from FPC decompositions; however these objects are unknown in practice. In this article, we propose a method for obtaining correct curve estimates by accounting for uncertainty in FPC decompositions. Additionally, pointwise and simultaneous confidence intervals that account for both model- and decomposition-based variability are constructed. Standard mixed model representations of functional expansions are used to construct curve estimates and variances conditional on a specific decomposition. Iterated expectation and variance formulas combine model-based conditional estimates across the distribution of decompositions. A bootstrap procedure is implemented to understand the uncertainty in principal component decomposition quantities. Our method compares favorably to competing approaches in simulation studies that include both densely and sparsely observed functions. We apply our method to sparse observations of CD4 cell counts and to dense white-matter tract profiles. Code for the analyses and simulations is publicly available, and our method is implemented in the R package refund on CRAN.
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Affiliation(s)
- J Goldsmith
- Department of Biostatistics, Columbia University, New York, New York 10032, USA.
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18
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Shinohara RT, Goldsmith J, Mateen FJ, Crainiceanu C, Reich DS. Predicting breakdown of the blood-brain barrier in multiple sclerosis without contrast agents. AJNR Am J Neuroradiol 2012; 33:1586-90. [PMID: 22442041 DOI: 10.3174/ajnr.a2997] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND PURPOSE Disruption of the BBB in MS is associated with the development of new lesions and clinical relapses and signifies the presence of active inflammation. It is most commonly detected as enhancement on MR imaging performed with contrast agents that are costly and occasionally toxic. We investigated whether the BBB status in white matter lesions may be indirectly ascertained via examination of features on T1- and T2-weighted images obtained before the injection of a contrast agent. MATERIALS AND METHODS We considered 93 brain MR imaging studies on 16 patients that included T1-, T2-, and T2-weighted FLAIR images and predicted voxel wise enhancement after intravenous injection of a gadolinium chelate. We then used these voxel-level predictions to determine the presence or absence of abnormal enhancement anywhere in the brain. RESULTS On a voxel-by-voxel basis, enhancement can be predicted by using contrast-free measures with an AUC of 0.83 (95% CI, 0.80-0.87). At the whole-brain level, enhancement can be predicted with an AUC of 0.72 (95% CI, 0.62-0.82). CONCLUSIONS In many cases, breakdown of the BBB in acute MS lesions may be inferred without the need to inject an MR imaging contrast agent. The inference relies on intrinsic properties of tissue damage in acute lesions. Although contrast studies are more accurate, they may sometimes be unnecessary.
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Affiliation(s)
- R T Shinohara
- Department of Biostatistics, Johns Hopkins University, Baltimore, MD 21205, USA.
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19
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Kipling R, Amos V, Goldsmith J. User involvement in establishing a new young people's hospice. BMJ Support Palliat Care 2011. [DOI: 10.1136/bmjspcare-2011-000100.8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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20
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Ahmed AA, Wang X, Lu Z, Goldsmith J, Le XF, Grandjean G, Bartholomeusz G, Broom B, Bast RC. Modulating microtubule stability enhances the cytotoxic response of cancer cells to Paclitaxel. Cancer Res 2011; 71:5806-17. [PMID: 21775522 DOI: 10.1158/0008-5472.can-11-0025] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The extracellular matrix protein TGFBI enhances the cytotoxic response of cancer cells to paclitaxel by affecting integrin signals that stabilize microtubules. Extending the implications of this knowledge, we tested the more general hypothesis that cancer cell signals which increase microtubule stability before exposure to paclitaxel may increase its ability to stabilize microtubules and thereby enhance its cytotoxicity. Toward this end, we carried out an siRNA screen to evaluate how genetic depletion affected microtubule stabilization, cell viability, and apoptosis. High content microscopic analysis was carried out in the absence or presence of paclitaxel. Kinase knockdowns that stabilized microtubules strongly enhanced the effects of paclitaxel treatment. Conversely, kinase knockdowns that enhanced paclitaxel-mediated cytotoxicity sensitized cells to microtubule stabilization by paclitaxel. The siRNA screen identified several genes that have not been linked previously to microtubule regulation or paclitaxel response. Gene shaving and Bayesian resampling used to classify these genes suggested three pathways of paclitaxel-induced cell death related to apoptosis and microtubule stability, apoptosis alone, or neither process. Our results offer a functional classification of the genetic basis for paclitaxel sensitivity and they support the hypothesis that stabilizing microtubules prior to therapy could enhance antitumor responses to paclitaxel treatment.
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Affiliation(s)
- Ahmed Ashour Ahmed
- Department of Experimental Therapeutics, MD Anderson Cancer Center, University of Texas, Houston, Texas, USA.
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21
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Ahmed AA, Bast RC, Bowtell D, Goldsmith J. Abstract 4822: Nonsense mediated decay defines deleterious TP53 mutations and tumor aggressiveness in ovarian cancer. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-4822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Genetic mutations leading to premature termination of protein translation, nonsense mutations, result in aberrant precursor mRNA processing and subsequent UPF1-dependent exosomal degradation of mRNA. The significance of this surveillance mechanism in controlling the expression of key mutated tumor suppressor genes in cancer in vivo has remained unclear. We have recently shown that TP53 mutations are almost invariably present in high-grade serous ovarian cancers (Ahmed at al., Journal of Pathology, 2010;221:49) and that about one third of such mutations are nonsense. We have now tested the hypothesis that nonsense mutations induce nonsense mediated decay resulting in TP53 mRNA depletion. We analyzed microarray expression profiling data from 136 epithelial ovarian cancers with known TP53 mutation status and found a strikingly statistically significant underexpression of TP53 mRNA transcript in cancers with truncating mutations (p<0.0001) compared to other types of mutations. This effect allowed the identification of a class of TP53-non-expressing serous epithelial cancers that comprised all TP53 truncating mutations. We next conducted a systematic analysis of 18 publically available expression profiling ovarian cancer studies published at the Gene Expression Omnibus database. We validated the results by showing that cancers that had nonsense mutations had a significantly lower TP53 expression irrespective of stage. Importantly, this systematic analysis of multiple independent data set established that lack of TP53 expression was, almost exclusively, a feature of high grade serous cancers and invasion as opposed to low grade disease or tumors of low malignant potential (p<0.0001 and p=0.002, respectively). Expression profiling analysis revealed that cancers with truncating mutations had a distinct gene expression signature compared to those with missense mutations. This signature was enriched for genes that regulated angiogenesis such as CSPG4 and metabolism. Surprisingly, however, the magnitude of expression differences was not high. Based on these results, we propose a model for the biogenesis of a subset of high-grade serous ovarian cancers that is defined by nonsense mediated decay of nonsense TP53 mutations.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4822. doi:10.1158/1538-7445.AM2011-4822
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Affiliation(s)
| | | | - David Bowtell
- 3Peter MacCallum Cancer Centre, Melbourne, Australia
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22
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Ahmed AA, Goldsmith J, Fokt I, Le XF, Krzysko KA, Lesyng B, Bast RC, Priebe W. A genistein derivative, ITB-301, induces microtubule depolymerization and mitotic arrest in multidrug-resistant ovarian cancer. Cancer Chemother Pharmacol 2011; 68:1033-44. [PMID: 21340606 PMCID: PMC3180612 DOI: 10.1007/s00280-011-1575-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Accepted: 01/27/2011] [Indexed: 12/31/2022]
Abstract
Purpose To investigate the mechanistic basis of the anti-tumor effect of the compound ITB-301. Methods Chemical modifications of genistein have been introduced to improve its solubility and efficacy. The anti-tumor effects were tested in ovarian cancer cells using proliferation assays, cell cycle analysis, immunofluorescence, and microscopy. Results In this work, we show that a unique glycoside of genistein, ITB-301, inhibits the proliferation of SKOv3 ovarian cancer cells. We found that the 50% growth inhibitory concentration of ITB-301 in SKOv3 cells was 0.5 μM. Similar results were obtained in breast cancer, ovarian cancer, and acute myelogenous leukemia cell lines. ITB-301 induced significant time- and dose-dependent microtubule depolymerization. This depolymerization resulted in mitotic arrest and inhibited proliferation in all ovarian cancer cell lines examined including SKOv3, ES2, HeyA8, and HeyA8-MDR cells. The cytotoxic effect of ITB-301 was dependent on its induction of mitotic arrest as siRNA-mediated depletion of BUBR1 significantly reduced the cytotoxic effects of ITB-301, even at a concentration of 10 μM. Importantly, efflux-mediated drug resistance did not alter the cytotoxic effect of ITB-301 in two independent cancer cell models of drug resistance. Conclusion These results identify ITB-301 as a novel anti-tubulin agent that could be used in cancers that are multidrug resistant. We propose a structural model for the binding of ITB-301 to α- and β-tubulin dimers on the basis of molecular docking simulations. This model provides a rationale for future work aimed at designing of more potent analogs. Electronic supplementary material The online version of this article (doi:10.1007/s00280-011-1575-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ahmed Ashour Ahmed
- Department of Experimental Therapeutics, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd, Unit 422, Houston, TX 77030, USA
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23
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Abstract
We investigate the computational complexity of testing dominance and consistency in CP-nets. Previously, the complexity of dominance has been determined for restricted classes in which the dependency graph of the CP-net is acyclic. However, there are preferences of interest that define cyclic dependency graphs; these are modeled with general CP-nets. In our main results, we show here that both dominance and consistency for general CP-nets are PSPACE-complete. We then consider the concept of strong dominance, dominance equivalence and dominance incomparability, and several notions of optimality, and identify the complexity of the corresponding decision problems. The reductions used in the proofs are from STRIPS planning, and thus reinforce the earlier established connections between both areas.
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24
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Buxbaum JD, Cai G, Nygren G, Chaste P, Delorme R, Goldsmith J, Råstam M, Silverman JM, Hollander E, Gillberg C, Leboyer M, Betancur C. Mutation analysis of the NSD1 gene in patients with autism spectrum disorders and macrocephaly. BMC Med Genet 2007; 8:68. [PMID: 18001468 PMCID: PMC2248565 DOI: 10.1186/1471-2350-8-68] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Accepted: 11/14/2007] [Indexed: 11/10/2022]
Abstract
Background Sotos syndrome is an overgrowth syndrome characterized by macrocephaly, advanced bone age, characteristic facial features, and learning disabilities, caused by mutations or deletions of the NSD1 gene, located at 5q35. Sotos syndrome has been described in a number of patients with autism spectrum disorders, suggesting that NSD1 could be involved in other cases of autism and macrocephaly. Methods We screened the NSD1 gene for mutations and deletions in 88 patients with autism spectrum disorders and macrocephaly (head circumference 2 standard deviations or more above the mean). Mutation analysis was performed by direct sequencing of all exons and flanking regions. Dosage analysis of NSD1 was carried out using multiplex ligation-dependent probe amplification. Results We identified three missense variants (R604L, S822C and E1499G) in one patient each, but none is within a functional domain. In addition, segregation analysis showed that all variants were inherited from healthy parents and in two cases were also present in unaffected siblings, indicating that they are probably nonpathogenic. No partial or whole gene deletions/duplications were observed. Conclusion Our findings suggest that Sotos syndrome is a rare cause of autism spectrum disorders and that screening for NSD1 mutations and deletions in patients with autism and macrocephaly is not warranted in the absence of other features of Sotos syndrome.
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Affiliation(s)
- Joseph D Buxbaum
- Laboratory of Molecular Neuropsychiatry, Mount Sinai School of Medicine, New York, USA.
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25
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Buxbaum JD, Cai G, Chaste P, Nygren G, Goldsmith J, Reichert J, Anckarsäter H, Rastam M, Smith CJ, Silverman JM, Hollander E, Leboyer M, Gillberg C, Verloes A, Betancur C. Mutation screening of the PTEN gene in patients with autism spectrum disorders and macrocephaly. Am J Med Genet B Neuropsychiatr Genet 2007; 144B:484-91. [PMID: 17427195 PMCID: PMC3381648 DOI: 10.1002/ajmg.b.30493] [Citation(s) in RCA: 223] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Mutations in the PTEN gene are associated with a broad spectrum of disorders, including Cowden syndrome (CS), Bannayan-Riley-Ruvalcaba syndrome, Proteus syndrome, and Lhermitte-Duclos disease. In addition, PTEN mutations have been described in a few patients with autism spectrum disorders (ASDs) and macrocephaly. In this study, we screened the PTEN gene for mutations and deletions in 88 patients with ASDs and macrocephaly (defined as >or=2 SD above the mean). Mutation analysis was performed by direct sequencing of all exons and flanking regions, as well as the promoter region. Dosage analysis of PTEN was carried out using multiplex ligation-dependent probe amplification (MLPA). No partial or whole gene deletions were observed. We identified a de novo missense mutation (D326N) in a highly conserved amino acid in a 5-year-old boy with autism, mental retardation, language delay, extreme macrocephaly (+9.6 SD) and polydactyly of both feet. Polydactyly has previously been described in two patients with Lhermitte-Duclos disease and CS and is thus likely to be a rare sign of PTEN mutations. Our findings suggest that PTEN mutations are a relatively infrequent cause of ASDs with macrocephaly. Screening of PTEN mutations is warranted in patients with autism and pronounced macrocephaly, even in the absence of other features of PTEN-related tumor syndromes.
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Affiliation(s)
- Joseph D. Buxbaum
- Laboratory of Molecular Neuropsychiatry, Mount Sinai School of Medicine, New York, New York
- Department of Psychiatry and Seaver Autism Research Center, Mount Sinai School of Medicine, New York, New York
| | - Guiqing Cai
- Laboratory of Molecular Neuropsychiatry, Mount Sinai School of Medicine, New York, New York
- Department of Psychiatry and Seaver Autism Research Center, Mount Sinai School of Medicine, New York, New York
| | - Pauline Chaste
- INSERM U513, Créteil, France
- Service de Psychopathologie de l’Enfant et de l’Adolescent, AP-HP, Hôpital Robert Debré, Paris, France
| | - Gudrun Nygren
- Department of Child and Adolescent Psychiatry, Goteborg University, Goteborg, Sweden
| | - Juliet Goldsmith
- Laboratory of Molecular Neuropsychiatry, Mount Sinai School of Medicine, New York, New York
- Department of Psychiatry and Seaver Autism Research Center, Mount Sinai School of Medicine, New York, New York
| | - Jennifer Reichert
- Laboratory of Molecular Neuropsychiatry, Mount Sinai School of Medicine, New York, New York
- Department of Psychiatry and Seaver Autism Research Center, Mount Sinai School of Medicine, New York, New York
| | - Henrik Anckarsäter
- Department of Child and Adolescent Psychiatry, Goteborg University, Goteborg, Sweden
| | - Maria Rastam
- Department of Child and Adolescent Psychiatry, Goteborg University, Goteborg, Sweden
| | - Christopher J. Smith
- Department of Psychiatry and Seaver Autism Research Center, Mount Sinai School of Medicine, New York, New York
| | - Jeremy M. Silverman
- Department of Psychiatry and Seaver Autism Research Center, Mount Sinai School of Medicine, New York, New York
| | - Eric Hollander
- Department of Psychiatry and Seaver Autism Research Center, Mount Sinai School of Medicine, New York, New York
| | - Marion Leboyer
- INSERM U513, Créteil, France
- Department of Psychiatry, AP-HP, Hôpital Henri Mondor et Hôpital Albert Chenevier, Créteil, France
| | - Christopher Gillberg
- Department of Child and Adolescent Psychiatry, Goteborg University, Goteborg, Sweden
- Department of Psychiatry, Saint George’s Hospital Medical School, London, United Kingdom
| | - Alain Verloes
- Department of Genetics, AP-HP, Hôpital Robert Debré, Paris, France
| | - Catalina Betancur
- INSERM U513, Créteil, France
- Correspondence to: Dr. Catalina Betancur, INSERM U513, Faculté de Médecine, 8 rue du Général Sarrail, 94010 Créteil, Cedex, France.
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Buxbaum J, Barreto M, Cai G, Goldsmith J, Hollander E, Ramoz N, Reichert J, Sakurai T, Silverman J, Smith C. [P28]: Linkage and association analysis across an autism susceptibility locus on chromosome 2q in autism: Functional analysis of AGC1/SLC25A12. Int J Dev Neurosci 2006. [DOI: 10.1016/j.ijdevneu.2006.09.092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
| | | | - G. Cai
- Mount Sinai Medical CenterUSA
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Patti ME, McMahon G, Mun EC, Bitton A, Holst JJ, Goldsmith J, Hanto DW, Callery M, Arky R, Nose V, Bonner-Weir S, Goldfine AB. Severe hypoglycaemia post-gastric bypass requiring partial pancreatectomy: evidence for inappropriate insulin secretion and pancreatic islet hyperplasia. Diabetologia 2005; 48:2236-40. [PMID: 16195867 DOI: 10.1007/s00125-005-1933-x] [Citation(s) in RCA: 292] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Accepted: 06/13/2005] [Indexed: 01/09/2023]
Abstract
AIMS/HYPOTHESIS Postprandial hypoglycaemia following gastric bypass for obesity is considered a late manifestation of the dumping syndrome and can usually be managed with dietary modification. We investigated three patients with severe postprandial hypoglycaemia and hyperinsulinaemia unresponsive to diet, octreotide and diazoxide with the aim of elucidating the pathological mechanisms involved. METHODS Glucose, insulin, and C-peptide were measured in the fasting and postprandial state, and insulin secretion was assessed following selective intra-arterial calcium injection. Pancreas histopathology was assessed in all three patients. RESULTS All three patients had evidence of severe postprandial hyperinsulinaemia and hypoglycaemia. In one patient, reversal of gastric bypass was ineffective in reversing hypoglycaemia. All three patients ultimately required partial pancreatectomy for control of neuroglycopenia; pancreas pathology of all patients revealed diffuse islet hyperplasia and expansion of beta cell mass. CONCLUSIONS/INTERPRETATION These findings suggest that gastric bypass-induced weight loss may unmask an underlying beta cell defect or contribute to pathological islet hyperplasia, perhaps via glucagon-like peptide 1-mediated pathways.
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Affiliation(s)
- M E Patti
- Research Division, Joslin Diabetes Center, Boston, MA 02215, USA.
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Colquhoun DM, Jackson R, Walters M, Hicks BJ, Goldsmith J, Young P, Strakosch C, Kostner KM. Effects of simvastatin on blood lipids, vitamin E, coenzyme Q10 levels and left ventricular function in humans. Eur J Clin Invest 2005; 35:251-8. [PMID: 15816994 DOI: 10.1111/j.1365-2362.2005.01486.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND As statin therapy has been reported to reduce antioxidants such as vitamin E and coenzyme Q10 and there are indications that this reduction may cause impairment of left ventricular function (LVF), we studied the influence of simvastatin on LVF and serum vitamin E and coenzyme Q10 levels in humans. MATERIAL AND METHODS We assessed the effect of simvastatin on left ventricular function and coenzyme Q10 levels in 21 (11 male, 10 female) hypercholesterolaemic subjects (mean age = 56 years) with normal LVF, over a period of 6 months. Subjects were re-tested after a 1-month wash-out period (7 months). Echocardiography was performed on all subjects before commencement of simvastatin (20 mg day(-1)), and at 1, 3, 6 and 7 months after initiation of treatment. Fasting blood samples were also collected at these intervals to assess lipids, apoproteins, vitamin E and coenzyme Q10. RESULTS Serum lipids showed the expected reductions. Plasma vitamin E and coenzyme Q10 levels were reduced by 17 +/- 4% (P < 0.01) and 12 +/- 4% (P < 0.03) at 6 months. However, the coenzyme Q10/LDL-cholesterol ratio and vitamin E/LDL-cholesterol ratio increased significantly. Left ventricular ejection fraction (EF) decreased transiently after 1 month, while no significant change was observed at 3 and 6 months. Other markers of left ventricular function did not change significantly at any time point. CONCLUSION Despite reduced plasma vitamin E and coenzyme Q10, 20 mg of simvastatin therapy is associated with a significantly increased coenzyme Q10/LDL-cholesterol ratio and vitamin E/LDL-cholesterol ratio. Simvastatin treatment is not associated with impairment in left ventricular systolic or diastolic function in hypercholesterolaemic subjects after 6 months of treatment.
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Affiliation(s)
- D M Colquhoun
- Greenslopes Private Hospital and The Wesley Hospital, Brisbane, Australia.
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29
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Goldsmith J, McKnight C, Dickson S, Heenan M, Berezowski R. Miconazole and clobazam; a useful interaction in Dravet's syndrome? Arch Dis Child 2004; 89:89. [PMID: 14709525 PMCID: PMC1755892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/03/2023]
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Atkinson T, Hall C, Skoda-Smith S, Goldsmith J, Kirkham P. Splice variant in T-cell receptor ξ chain occurs in a region with homology to G-protein γ chain. J Allergy Clin Immunol 2003. [DOI: 10.1016/s0091-6749(03)81015-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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31
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Lessem J, Drisko C, Greenwell H, Persson R, Newman H, Smart G, Hopkins L, Parameshwar J, Fishbein D, Partridge C, Bhat G, Goldsmith J. Are cardiac transplant patients more likely to have periodontitis? A case record study. J Int Acad Periodontol 2002; 4:95-100. [PMID: 12670088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
In several large epidemiological studies chronic periodontitis has been implicated as an additional risk factor, independent of other risk factors, for the development of ischaemic heart disease. The underlying mechanism is thought to be a localised infection giving rise to an inflammatory host response, and some experimental data agree with this hypothesis. Recently, however, some studies have questioned the post dated relationship between the two diseases. The current case-record study was undertaken to evaluate the prevalence of chronic periodontitis and the severity of such periodontal disease in a heart transplant population, assuming the latter represented a relatively severely compromised cardiovascular patient population. The study demonstrated that 76% of the patients had various degrees of periodontal disease prior to undergoing a heart transplant. Thus, it is possible that a relationship between cardiovascular disease and periodontal disease exists, but further, large intervention studies will be needed to confirm such a conclusion.
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Affiliation(s)
- Jan Lessem
- OraPharma Inc, Warminster, PA 18974, USA.
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Moch SD, Goldsmith J. Clinicians use group-wise effort for innovations. Reflect Nurs Leadersh 2002; 26:32-4, 45. [PMID: 11987258] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Affiliation(s)
- S D Moch
- University of Wisconsin-Eau Claire, Eau Claire, Wis., USA
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McDonald A, Goldsmith J. Strategizing your career. Reflect Nurs Leadersh 2002; 26:15-9, 43. [PMID: 11987338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
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Goldsmith J. He connects health care's dots along information superhighway. Interview by Patrick Mullen. Manag Care 2001; 10:53-5, 59-61. [PMID: 11392729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
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Abstract
We show that for several variations of partially observable Markov decision processes, polynomial-time algorithms for finding control policies are unlikely to or simply don't have guarantees of finding policies within a constant factor or a constant summand of optimal. Here ``unlikely'' means ``unless some complexity classes collapse,'' where the collapses considered are P=NP, P=PSPACE, or P=EXP. Until or unless these collapses are shown to hold, any control-policy designer must choose between such performance guarantees and efficient computation.
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Goldsmith J, Grimaldi P, Coile RJ, Nowicki M. Healthcare Financial Management's healthcare outlook. Healthc Financ Manage 2001; Suppl:7-11. [PMID: 11155282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Affiliation(s)
- J Goldsmith
- Health Futures, Inc., Charlottesville, Virginia, USA
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Frenkel LM, Capparelli EV, Dankner WM, Xu J, Smith IL, Ballow A, Culnane M, Read JS, Thompson M, Mohan KM, Shaver A, Robinson CA, Stempien MJ, Burchett SK, Melvin AJ, Borkowsky W, Petru A, Kovacs A, Yogev R, Goldsmith J, McFarland EJ, Spector SA. Oral ganciclovir in children: pharmacokinetics, safety, tolerance, and antiviral effects. The Pediatric AIDS Clinical Trials Group. J Infect Dis 2000; 182:1616-24. [PMID: 11069232 DOI: 10.1086/317600] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2000] [Revised: 09/12/2000] [Indexed: 11/03/2022] Open
Abstract
The pharmacokinetics, safety, tolerance, and antiviral effects of ganciclovir (Gcv) administered orally were evaluated in 36 children infected with cytomegalovirus (CMV) who were severely immunocompromised by infection with human immunodeficiency virus type 1. In this dose-escalation study, 30 mg/kg of Gcv administered every 8 h produced serum levels similar to the dose (1 g/8 h) effective for maintenance treatment of CMV retinitis in adults. In older children, serum Gcv concentrations were similar after the administration of capsules and suspension. All doses (10-50 mg/kg/8 h) studied were safe and, except for the volume of suspension or number of pills, were well tolerated. Oral Gcv was associated with a decrease in the detection of CMV by culture or polymerase chain reaction. CMV disease occurred in 3 children during the study: one developed Gcv resistance, another had harbored resistant virus at study entry, and a third had wild-type CMV
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Affiliation(s)
- L M Frenkel
- Divisions of Infectious Diseases and Virology, Dept. of Pediatrics and Laboratory Medicine, University of Washington, Seattle, WA 98105, USA.
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Fleming DR, Goldsmith J, Goldsmith GH, Stevens DA, Herzig RH. Mobilization of peripheral blood stem cells in high-risk breast cancer patients using G-CSF after standard dose docetaxel. J Hematother Stem Cell Res 2000; 9:855-60. [PMID: 11177597 DOI: 10.1089/152581600750062282] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Chemotherapy, in addition to recombinant growth factors, has been effective in mobilizing stem cells. Unfortunately, the use of chemotherapy for this purpose has resulted in profound myelosuppression and increased morbidity. Docetaxel, the single most active agent in the treatment of advanced breast cancer, was evaluated for its potential to mobilize stem cells when given at conventional doses followed by granulocyte colony-stimulating factor (G-CSF). Sixteen high-risk breast cancer patients were mobilized with a regimen consisting of docetaxel (100 mg/m2) followed by daily G-CSF (10 microg/kg), beginning 72 h after the docetaxel, and continuing until completion of the apheresis. The median white blood cell count (WBC) nadir was 1,000/microl (range 500 to 4000/microl ) occurring a median of 6 days (range 4 to 9 days) after the docetaxel. No patient experienced a neutropenic febrile episode due to the mobilization regimen. The median time interval for initiating the apheresis was 8 days (range 6 to 11 days) following the docetaxel. The median number of apheresis was 2 (range 1 to 3) in each patient. Stem cell recovery as measured by the CD34 cell count x 10(6)/kg was a median of 5.2 (range 1.4 to 15.1). A significant correlation was found between CFU-GM, BFU-E, and CFU-GEMM/kg and CD34 cells/kg (r = 0.891, 0.945, and 0.749, respectively, p < 0.001). When our results were compared to a matched cohort receiving G-CSF alone, the docetaxel group demonstrated a superior CD34 cells/kg yield (p = <0.001). Following myeloablative chemotherapy consisting of thiotepa and cyclophosphamide with or without carboplatinum, the hematopoetic recovery determined by an absolute neutrophil count (ANC) of greater than 500/microl and an unsupported platelet count of > or =20,000/microl for 48 h, was a median of 10 days (range 9 to 14 days) and 10 days (range 8 to 30 days), respectively. The results demonstrate that conventional dose docetaxel, combined with G-CSF, is an effective mobilization regimen with minimal toxicity in high-risk breast cancer patients.
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Affiliation(s)
- D R Fleming
- University of Louisville Blood and Marrow Transplant Program, James Graham Brown Cancer Center, Room 230, 529 South Jackson Street, Louisville, KY 40202, USA.
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Abstract
Managed care firms have been under siege in the political system and the marketplace for the past few years. The rise of the Internet has brought into being powerful new electronic tools for automating administrative and financial processes in health insurance. These tools may enable new firms or employers to create custom-designed networks connecting their workers and providers, bypassing health plans altogether. Alternatively, health plans may use these tools to create a new consumer-focused business model. While some disintermediation of managed care plans may occur, the barriers to adoption of Internet tools by established plans are quite low. Network computing may provide important leverage for health plans not only to retain their franchises but also to improve their profitability and customer service.
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Affiliation(s)
- J Goldsmith
- Health Futures, Charlottesville, Virginia, USA.
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40
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Affiliation(s)
- J Goldsmith
- Health Futures, Inc., Charlottesville, Virginia, USA
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Wain RA, Veith FJ, Marin ML, Ohki T, Suggs WD, Cynamon J, Goldsmith J, Sanchez LA. Analysis of endovascular graft treatment for aortoiliac occlusive disease: what is its role based on midterm results? Ann Surg 1999; 230:145-51. [PMID: 10450727 PMCID: PMC1420856 DOI: 10.1097/00000658-199908000-00003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To analyze the authors' midterm results (up to 4 years) using endovascular grafts to treat aortoiliac occlusive disease in patients with limb-threatening ischemia. SUMMARY BACKGROUND DATA Endovascular grafts are being used to manage some aortoiliac lesions formerly treated by aortofemoral or extraanatomic bypass grafts. However, widespread acceptance of these new grafts depends on their late patency and clinical utility. METHODS Between January 1993 and December 1997, 52 patients with aortoiliac occlusive disease were treated with endovascular grafts. The primary indication for treatment was gangrene or ulceration in 42 patients (81%) and rest pain in 10 patients (19%). Sixteen patients had symptomatic contralateral limbs that were also treated, and 27 (52%) patients required a synchronous infrainguinal bypass. Results up to 4 years were evaluated by life table analysis. RESULTS Forty-six (88%) of the patients had complete follow-up of 3 to 57 months (median 22 months). Six patients were lost to follow-up at a mean of 20 months after surgery. The 4-year primary and secondary patency rates for the endovascular grafts were 66.1% and 72.3% respectively. Six patients required a major amputation, and the limb salvage rate was 88.7%. Four-year patient survival was 37%, with 23 patients dying during this follow-up period. CONCLUSIONS Endovascular grafts can often be used when conventional procedures are contraindicated or technically impractical. These grafts are a valuable alternative to extraanatomic and aortofemoral bypasses in high-risk patients with aortoiliac occlusive disease and critical ischemia.
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Affiliation(s)
- R A Wain
- Department of Surgery, Montefiore Medical Center, Bronx, New York 10467, USA
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Carel R, Levitas-Langman A, Kordysh E, Goldsmith J, Friger M. Case-referent study on occupational risk factors for bladder cancer in southern Israel. Int Arch Occup Environ Health 1999; 72:304-8. [PMID: 10447660 DOI: 10.1007/s004200050379] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
OBJECTIVE To evaluate the possible association between occupational exposures (risk factors) and male bladder cancer in the Negev region (southern Israel) to enable preventive strategies to be applied. METHODS A total of 92 male bladder cancer patients, diagnosed at a regional medical center between 1989 and 1993, were studied by interview and compared with 92 males without oncological disease after matching by age and country of origin. A special questionnaire was developed to gather information on demography, life-time occupational history, smoking habits, coffee consumption, and health status. Statistical analysis of the case-referent data was done using the SPSS-5 package for performance of the chi-square test, conditional logistic regression, and multiple classification analysis. RESULTS Significant associations were found between bladder cancer occurrence and (1) three different groups of occupational exposures [a - solvents (P = 0.002, OR not computed due to the lack of exposed persons among referents), b - dusts (P = 0. 02; OR = 4.67), and c - exposure to multiple chemicals (P < 0.001, OR = 6.25); (2) nephrolithiasis (P = 0.02, OR = 11.00); and (3) cigarette smoking (P = 0.01, OR = 1.87). CONCLUSIONS Certain types of occupational exposure, different from that to aromatic amines and dyes, may be considered as contributing factors in the epidemiology of bladder cancer. Better identification of these chemicals and the work processes where they are used may help in abating such exposures, thus leading to a reduction in the risk for this relatively common cancer.
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Affiliation(s)
- R Carel
- Department of Occupational Medicine, Division of Community Medicine, Faculty of Health Sciences, Ben-Gurion University, Beer-Sheva, 84120, Israel.
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Bichara J, Greenwell H, Drisko C, Wittwer JW, Vest TM, Yancey J, Goldsmith J, Rebitski G. The effect of postsurgical naproxen and a bioabsorbable membrane on osseous healing in intrabony defects. J Periodontol 1999; 70:869-77. [PMID: 10476894 DOI: 10.1902/jop.1999.70.8.869] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Previous reports in the literature have shown that non-steroidal anti-inflammatory drugs (NSAID) may affect osseous tissues by either stimulating or inhibiting bone formation. This effect can be drug specific and different NSAIDs may produce opposite results. There are also reports showing that NSAIDs inhibit bone loss due to inflammatory disease process. The purpose of this randomized, controlled, blinded, clinical investigation was to determine the effect of a one week course of postsurgical naproxen on the osseous healing in intrabony defects. METHODS Twenty-four vertical osseous defects in 24 patients were treated with either a bioabsorbable membrane plus twice daily postsurgical naproxen 500 mg for one week (test or GPN group) or with a polylactide bioabsorbable membrane alone (control or GA group). Twelve patients were included in each group. Treatment was performed on either 2- or 3-wall or combination defects. All measurements were taken from a stent by a calibrated, blinded examiner and open measurements were repeated at the 9-month second stage surgery. Power analysis to determine superiority of naproxen treatment showed that a 12 per group sample size would yield 87% power to detect a 2.0 mm difference and 64% power to detect a 1.5 mm difference. RESULTS Open defect measurements from baseline to 9 months showed a statistically significant (P < 0.05) mean defect fill of 1.96 +/- 1.27 mm and 2.04 +/- 1.71 for the GPN and GA groups, respectively. This corresponded to a mean defect fill of 42% and a mean defect resolution of approximately 75% for both groups. The differences between GPN and GA groups were not statistically significant (P > 0.05). Defect fill of > or = 50% was seen in 6 defects (50%) in the GPN group and in 5 defects (42%) in the GA group. CONCLUSIONS The administration of postsurgical naproxen failed to produce osseous healing that was statistically superior to that obtained with polylactide bioabsorbable membranes alone.
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Affiliation(s)
- J Bichara
- Department of Periodontics, Endodontics and Dental Hygiene, School of Dentistry, University of Louisville, KY 40292, USA
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Vest TM, Greenwell H, Drisko C, Wittwer JW, Bichara J, Yancey J, Goldsmith J, Rebitski G. The effect of postsurgical antibiotics and a bioabsorbable membrane on regenerative healing in Class II furcation defects. J Periodontol 1999; 70:878-87. [PMID: 10476895 DOI: 10.1902/jop.1999.70.8.878] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND The purpose of this randomized, controlled, blinded, clinical investigation was to determine the effect of postsurgical antibiotics on osseous healing in Class II furcation defects. METHODS Twenty-four Class II furcation defects in 24 patients were treated with either a polylactide bioabsorbable membrane, demineralized freeze-dried bone allograft (DFDBA) plus antibiotics (GBA or test group) or with a polylactide membrane and DFDBA alone (GB or control group). Twelve patients were included in each group. The antibiotic regimen consisted of ciprofloxacin 250 mg twice daily and metronidazole 250 mg tid for 1 week followed by a 7-week regimen of doxycycline hyclate 50 mg daily. Treatment was performed on either mandibular buccal or lingual, or maxillary buccal Class II furcation defects. Defects were randomly selected by a coin toss for treatment and all open and closed measurements were performed by a blinded examiner. Final open and closed measures from a stent were repeated at the 9-month second stage surgery. Power analysis to determine superiority of antibiotic treatment showed that a 12 per group sample size would yield 93% power to detect a 1.5 mm difference and 64% power to detect a 1 mm difference. RESULTS Mean open horizontal probing depth reductions at 9 months were greater for the GBA group than for the GB group (2.92+/-1.78 versus 2.50+/-1.62 mm); however, these differences were not statistically significant. Seven of 12 furcations (58%) in the GBA group demonstrated >50% vertical defect fill at 9 months compared to 8 of 12 furcations (67%) in the GB group. There were no significant differences in mean open horizontal probing depth reduction between smokers and non-smokers in either the GBA or GB groups. Membrane exposure did not appear to affect regenerative healing in either the GBA or GB groups. CONCLUSIONS The administration of postsurgical antibiotics did not produce statistically superior osseous healing of Class II furcation defects. This result may be attributable to membrane design which facilitates connective tissue ingrowth, thereby preventing bacterial downgrowth and contamination of the newly regenerated tissues.
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Affiliation(s)
- T M Vest
- Department of Periodontics, Endodontics and Dental Hygiene, School of Dentistry, University of Louisville, KY 40292, USA
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Goldsmith J. WHO looks at Dr. Kim's community model. Reflections 1999; 24:13. [PMID: 10214327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Affiliation(s)
- J Goldsmith
- Health Futures, Inc., Charlottesville, VA, USA
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Goldsmith J. Are HMOs really a dying breed? Healthc Forum J 1998; 41:52-3; author reply 54. [PMID: 10346620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/13/2023]
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Goldsmith J. Three predictable crises in the health system and what to do about them. Healthc Forum J 1998; 41:42-4, 46. [PMID: 10346618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Affiliation(s)
- J Goldsmith
- Health Futures, Inc., Charlottesville, VA, USA
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Avnon L, Oryan I, Kordysh E, Goldsmith J, Sobel R, Friger M. Cancer incidence and risks in selected agricultural settlements in the Negev of Israel. Arch Environ Health 1998; 53:336-43. [PMID: 9766478 DOI: 10.1080/00039899809605718] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Medical staff of two Negev kibbutzim invited epidemiologists to help them investigate cancer rates among their members. Our objectives were (a) to determine whether the cancer rate in the kibbutzim was elevated or abnormal and (b) to determine the role of agricultural and other relevant exposures if cancer incidence was elevated. We validated cases of cancer by kibbutz records and by surveying other information; we computed expected values on the basis of the age-sex-calendar period and site-specific cancer incidence rates reported by the Israel Cancer Registry for the entire population; and we compared the data for the 2 kibbutzim with data derived for similar age and sex groups in 2 other kibbutzim, which were assumed not to have increased cancer rates. In addition, we planned and conducted a case-referent study, including the design, pretest, and use of questionnaires, including data about lifetime exposures (i.e., type of work and its duration, agricultural and industrial chemicals, smoking and alcohol use, demographic variables, health experiences, and family history). In only one of the kibbutzim, for which high cancer rates were suspected, was there significant excess for all sites in persons who were less than 40 y of age. In one of the "comparison" kibbutzim, we found increased cancer rates overall. Much of the excess in the high cancer kibbutzim was in hematological cancer (i.e., leukemia and lymphoma). Multiple years of work in fields, orchards, and landscape, as well as orchard work that commenced before 1960, were associated with increased risk of cancer (p < .08). We also found an association between cancer rate and numbers of industrial chemicals used (p < .08). Pipe and cigarette smoking were also associated with increased cancer incidence. In the multivariate analysis, the association with calendar year in which orchard work was started and multiple exposures to industrial chemicals was stronger than associations noted in the univariate analyses. Although duration of agricultural work or multiple industrial exposures were clearly associated with increase in cancer risk, we were unable to identify the causal role of specific agent(s). Nonetheless, educational programs for cancer prevention can be based, in part, on the results of such a study.
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Affiliation(s)
- L Avnon
- Department of Medicine, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel
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Abstract
We examine the computational complexity of testing and finding small plans in probabilistic planning domains with both flat and propositional representations. The complexity of plan evaluation and existence varies with the plan type sought; we examine totally ordered plans, acyclic plans, and looping plans, and partially ordered plans under three natural definitions of plan value. We show that problems of interest are complete for a variety of complexity classes: PL, P, NP, co-NP, PP, NP^PP, co-NP^PP, and PSPACE. In the process of proving that certain planning problems are complete for NP^PP, we introduce a new basic NP^PP-complete problem, E-MAJSAT, which generalizes the standard Boolean satisfiability problem to computations involving probabilistic quantities; our results suggest that the development of good heuristics for E-MAJSAT could be important for the creation of efficient algorithms for a wide variety of problems.
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