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Fitzgerald KC, Kim K, Smith MD, Aston SA, Fioravante N, Rothman AM, Krieger S, Cofield SS, Kimbrough DJ, Bhargava P, Saidha S, Whartenby KA, Green AJ, Mowry EM, Cutter GR, Lublin FD, Baranzini SE, De Jager PL, Calabresi PA. Early complement genes are associated with visual system degeneration in multiple sclerosis. Brain 2020; 142:2722-2736. [PMID: 31289819 DOI: 10.1093/brain/awz188] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 04/17/2019] [Accepted: 04/28/2019] [Indexed: 11/12/2022] Open
Abstract
Multiple sclerosis is a heterogeneous disease with an unpredictable course and a wide range of severity; some individuals rapidly progress to a disabled state whereas others experience only mild symptoms. Though genetic studies have identified variants that are associated with an increased risk of developing multiple sclerosis, no variants have been consistently associated with multiple sclerosis severity. In part, the lack of findings is related to inherent limitations of clinical rating scales; these scales are insensitive to early degenerative changes that underlie disease progression. Optical coherence tomography imaging of the retina and low-contrast letter acuity correlate with and predict clinical and imaging-based outcomes in multiple sclerosis. Therefore, they may serve as sensitive phenotypes to discover genetic predictors of disease course. We conducted a set of genome-wide association studies of longitudinal structural and functional visual pathway phenotypes in multiple sclerosis. First, we assessed genetic predictors of ganglion cell/inner plexiform layer atrophy in a discovery cohort of 374 patients with multiple sclerosis using mixed-effects models adjusting for age, sex, disease duration, optic neuritis and genetic ancestry and using a combination of single-variant and network-based analyses. For candidate variants identified in discovery, we conducted a similar set of analyses of ganglion cell/inner plexiform layer thinning in a replication cohort (n = 376). Second, we assessed genetic predictors of sustained loss of 5-letters in low-contrast letter acuity in discovery (n = 582) using multivariable-adjusted Cox proportional hazards models. We then evaluated candidate variants/pathways in a replication cohort. (n = 253). Results of both studies revealed novel subnetworks highly enriched for connected genes in early complement activation linked to measures of disease severity. Within these networks, C3 was the gene most strongly associated with ganglion cell/inner plexiform layer atrophy (P = 0.004) and C1QA and CR1 were top results in analysis of sustained low-contrast letter acuity loss. Namely, variant rs158772, linked to C1QA, and rs61822967, linked to CR1, were associated with 71% and 40% increases in risk of sustained LCLA loss, respectively, in meta-analysis pooling discovery and replication cohorts (rs158772: hazard ratio: 1.71; 95% confidence interval 1.30-2.25; P = 1.3 × 10-4; rs61822967: hazard ratio: 1.40; 95% confidence interval: 1.16-1.68; P = 4.1 × 10-4). In conclusion, early complement pathway gene variants were consistently associated with structural and functional measures of multiple sclerosis severity. These results from unbiased analyses are strongly supported by several prior reports that mechanistically implicated early complement factors in neurodegeneration.
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Affiliation(s)
| | - Kicheol Kim
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Matthew D Smith
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Sean A Aston
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Nicholas Fioravante
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Alissa M Rothman
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Stephen Krieger
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Stacey S Cofield
- Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL, USA
| | | | - Pavan Bhargava
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Shiv Saidha
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Katharine A Whartenby
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Ari J Green
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA.,Department of Ophthalmology, University of California San Francisco, San Francisco, CA, USA
| | - Ellen M Mowry
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Gary R Cutter
- Department of Biostatistics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Fred D Lublin
- Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Sergio E Baranzini
- Department of Neurology, University of California San Francisco, San Francisco, CA, USA
| | - Philip L De Jager
- Center for Translational and Computational Neuroimmunology, Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA.,Cell Circuits Program, Broad Institute, Cambridge, MA, USA
| | - Peter A Calabresi
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA.,Solomon Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Shahin Y, Rothman AM. Commentary on: evaluation of a newly developed 2D parametric parenchymal blood flow technique with an automated vessel suppression algorithm in patients with chronic thromboembolic pulmonary hypertension undergoing balloon pulmonary angioplasty. Clin Radiol 2019; 74:435-436. [PMID: 30910170 DOI: 10.1016/j.crad.2019.02.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Accepted: 02/12/2019] [Indexed: 11/25/2022]
Affiliation(s)
- Y Shahin
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK; Department of Clinical Radiology, Sheffield Teaching Hospitals, Sheffield, UK; INSIGNEO, Institute for in Silico Medicine, University of Sheffield, UK.
| | - A M Rothman
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK; INSIGNEO, Institute for in Silico Medicine, University of Sheffield, UK
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Thiel KW, Hernandez LI, Dassie JP, Thiel WH, Liu X, Stockdale KR, Rothman AM, Hernandez FJ, McNamara JO, Giangrande PH. Delivery of chemo-sensitizing siRNAs to HER2+-breast cancer cells using RNA aptamers. Nucleic Acids Res 2012; 40:6319-37. [PMID: 22467215 PMCID: PMC3401474 DOI: 10.1093/nar/gks294] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [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] [Indexed: 11/14/2022] Open
Abstract
Human epidermal growth factor receptor 2 (HER2) expression in breast cancer is associated with an aggressive phenotype and poor prognosis, making it an appealing therapeutic target. Trastuzumab, an HER2 antibody-based inhibitor, is currently the leading targeted treatment for HER2(+)-breast cancers. Unfortunately, many patients inevitably develop resistance to the therapy, highlighting the need for alternative targeted therapeutic options. In this study, we used a novel, cell-based selection approach for isolating 'cell-type specific', 'cell-internalizing RNA ligands (aptamers)' capable of delivering therapeutic small interfering RNAs (siRNAs) to HER2-expressing breast cancer cells. RNA aptamers with the greatest specificity and internalization potential were covalently linked to siRNAs targeting the anti-apoptotic gene, Bcl-2. We demonstrate that, when applied to cells, the HER2 aptamer-Bcl-2 siRNA conjugates selectively internalize into HER2(+)-cells and silence Bcl-2 gene expression. Importantly, Bcl-2 silencing sensitizes these cells to chemotherapy (cisplatin) suggesting a potential new therapeutic approach for treating breast cancers with HER2(+)-status. In summary, we describe a novel cell-based selection methodology that enables the identification of cell-internalizing RNA aptamers for targeting therapeutic siRNAs to HER2-expressing breast cancer cells. The future refinement of this technology may promote the widespread use of RNA-based reagents for targeted therapeutic applications.
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Affiliation(s)
- Kristina W Thiel
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA
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