1
|
Glickman JW, Dubin C, Dahabreh D, Han J, Del Duca E, Estrada YD, Zhang N, Kimmel GW, Singer G, Krueger JG, Pavel AB, Guttman‐Yassky E. An integrated scalp and blood biomarker approach suggests the systemic nature of alopecia areata. Allergy 2021; 76:3053-3065. [PMID: 33721346 DOI: 10.1111/all.14814] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [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: 10/28/2020] [Revised: 02/01/2021] [Accepted: 02/19/2021] [Indexed: 12/19/2022]
Abstract
BACKGROUND Alopecia areata (AA) is characterized by immune dysregulation in both scalp and blood, but a large-scale approach establishing biomarkers of AA incorporating both scalp tissue and serum compartments is lacking. We aimed to characterize the transcriptomic signature of AA lesional and nonlesional scalp compared to healthy scalp and determine its relationship with the blood proteome in the same individuals, with comparative correlations to clinical AA disease severity. METHODS We evaluated lesional and nonlesional scalp tissues and serum from patients with moderate-to-severe AA (n = 18) and healthy individuals (n = 8). We assessed 33,118 genes in AA scalp tissue using RNAseq transcriptomic evaluation and 340 inflammatory proteins in serum using OLINK high-throughput proteomics. Univariate and multivariate approaches were used to correlate disease biomarkers with Severity of Alopecia Tool (SALT). RESULTS A total of 608 inflammatory genes were differentially expressed in lesional AA scalp (fold change/FCH>1.5, false discovery rate/FDR<0.05) including Th1 (IFNG/IL12B/CXCL11), Th2 (IL13/CCL18), and T-cell activation-related (ICOS) products. Th1/Th2-related markers were significantly correlated with AA clinical severity in lesional/nonlesional tissue, while keratins (KRT35/KRT83/KRT81) were significantly downregulated in lesional compared to healthy scalp (p < .05). Expression of cardiovascular/atherosclerosis-related markers (MMP9/CCL2/IL1RL1/IL33R/ST2/AGER) in lesional scalp correlated with their corresponding serum expression (p < .05). AA scalp demonstrated significantly greater biomarker dysregulation compared to blood. An integrated multivariate approach combining scalp and serum biomarkers improved correlations with disease severity/SALT. CONCLUSION This study contributes a unique understanding of the phenotype of moderate-to-severe AA with an integrated scalp and serum biomarker model suggesting the systemic nature of the disease, advocating for the need for immune-based systemic treatment.
Collapse
Affiliation(s)
- Jacob W. Glickman
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Celina Dubin
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Dante Dahabreh
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Joseph Han
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Ester Del Duca
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Yeriel D. Estrada
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Ning Zhang
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Grace W. Kimmel
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - Giselle Singer
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| | - James G. Krueger
- Laboratory for Investigative Dermatology The Rockefeller University New York NY USA
| | - Ana B. Pavel
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
- Department of Biomedical Engineering The University of Mississippi University MS USA
| | - Emma Guttman‐Yassky
- Laboratory of Inflammatory Skin Diseases Department of Dermatology Icahn School of Medicine at Mount Sinai New York NY USA
| |
Collapse
|
2
|
Dubin C, Glickman JW, Del Duca E, Chennareddy S, Han J, Dahabreh D, Estrada YD, Zhang N, Kimmel GW, Singer G, Chowdhury M, Zheng AY, Angelov M, Gay-Mimbrera J, Ruano Ruiz J, Krueger JG, Pavel AB, Guttman-Yassky E. Scalp and serum profiling of frontal fibrosing alopecia reveals scalp immune and fibrosis dysregulation with no systemic involvement. J Am Acad Dermatol 2021; 86:551-562. [PMID: 34044102 DOI: 10.1016/j.jaad.2021.05.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 05/11/2021] [Indexed: 12/13/2022]
Abstract
BACKGROUND Frontal fibrosing alopecia (FFA) is a progressive, scarring alopecia of the frontotemporal scalp that poses a substantial burden on quality of life. Large-scale global profiling of FFA is lacking, preventing the development of effective therapeutics. OBJECTIVE To characterize FFA compared to normal and alopecia areata using broad molecular profiling and to identify biomarkers linked to disease severity. METHODS This cross-sectional study assessed 33,118 genes in scalp using RNA sequencing and 350 proteins in serum using OLINK high-throughput proteomics. Disease biomarkers were also correlated with clinical severity and a fibrosis gene set. RESULTS Genes differentially expressed in lesional FFA included markers related to Th1 (IFNγ/CXCL9/CXCL10), T-cell activation (CD2/CD3/CCL19/ICOS), fibrosis (CXCR3/FGF14/FGF22/VIM/FN1), T-regulatory (FOXP3/TGFB1/TGFB3), and Janus kinase/JAK (JAK3/STAT1/STAT4) (Fold changes [FCH]>1.5, FDR<.05 for all). Only one protein, ADM, was differentially expressed in FFA serum compared to normal (FCH>1.3, FDR<.05). Significant correlations were found between scalp biomarkers (IL-36RN/IL-25) and FFA severity, as well as between JAK/STAT and fibrosis gene-sets (r>.6; P <.05). LIMITATIONS This study was limited by a small sample size and predominantly female FFA patients. CONCLUSION Our data characterize FFA as an inflammatory condition limited to scalp, involving Th1/JAK skewing, with associated fibrosis and elevated T-regulatory markers, suggesting the potential for disease reversibility with JAK/STAT inhibition.
Collapse
Affiliation(s)
- Celina Dubin
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jacob W Glickman
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Ester Del Duca
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Dermatology, University of Magna Graecia, Catanzaro, Italy
| | - Sumanth Chennareddy
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Joseph Han
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Dante Dahabreh
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Yeriel D Estrada
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Ning Zhang
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Grace W Kimmel
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Giselle Singer
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Mashkura Chowdhury
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Andrew Y Zheng
- Macaulay Honors College at City University of New York (CUNY) Hunter College, New York, New York
| | - Michael Angelov
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jesús Gay-Mimbrera
- Immune-Mediated Inflammatory Skin Diseases Research Group, IMIBIC/Reina Sofia University Hospital/University of Cordoba, Cordoba, Spain
| | - Juan Ruano Ruiz
- Department of Dermatology, Reina Sofia University Hospital, Cordoba, Spain
| | - James G Krueger
- Laboratory of Investigative Dermatology, Rockefeller University, New York, New York
| | - Ana B Pavel
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York; Department of Biomedical Engineering, The University of Mississippi, Oxford, Mississippi.
| | - Emma Guttman-Yassky
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York; Laboratory of Investigative Dermatology, Rockefeller University, New York, New York.
| |
Collapse
|
3
|
Glickman JW, Dubin C, Renert-Yuval Y, Dahabreh D, Kimmel GW, Auyeung K, Estrada YD, Singer G, Krueger JG, Pavel AB, Guttman-Yassky E. Cross-sectional study of blood biomarkers of patients with moderate to severe alopecia areata reveals systemic immune and cardiovascular biomarker dysregulation. J Am Acad Dermatol 2020; 84:370-380. [PMID: 32376430 DOI: 10.1016/j.jaad.2020.04.138] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Revised: 04/23/2020] [Accepted: 04/27/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Although there is increased understanding of the alopecia areata (AA) pathogenesis based on studies in scalp tissues, little is known about its systemic profile. OBJECTIVE To evaluate the blood proteomic signature of AA and determine biomarkers associated with increased disease severity. METHODS In a cross-sectional study, we assessed 350 inflammatory and cardiovascular proteins using OLINK high-throughput proteomics in patients with moderate to severe AA (n = 35), as compared with healthy individuals (n = 36), patients with moderate to severe psoriasis (n = 19), and those with atopic dermatitis (n = 49). RESULTS Seventy-four proteins were significantly differentially expressed between AA and control individuals (false discovery rate, <.05) including innate immunity (interleukin [IL] 6/IL-8), T helper (Th) type 1 (interferon [IFN] γ/CXCL9/CXCL10/CXCL11), Th2 (CCL13/CCL17/CCL7), Th17 (CCL20/PI3/S100A12), and cardiovascular-risk proteins (OLR1/OSM/MPO/PRTN3). Eighty-six biomarkers correlated with AA clinical severity (P < .05), including Th1/Th2, and cardiovascular/atherosclerosis-related proteins, including SELP/PGLYRP1/MPO/IL-18/OSM (P < .05). Patients with AA totalis/universalis showed the highest systemic inflammatory tone, including cardiovascular risk biomarkers, compared to control individuals and even to patients with atopic dermatitis and those with psoriasis. The AA profile showed some Th1/Th2 differences in the setting of concomitant atopy. LIMITATIONS Our analysis was limited to 350 proteins. CONCLUSION This study defined the abnormalities of moderate to severe AA and associated circulatory biomarkers. It shows that AA has systemic immune, cardiovascular, and atherosclerosis biomarker dysregulation, suggesting the need for systemic treatment approaches.
Collapse
Affiliation(s)
- Jacob W Glickman
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Celina Dubin
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Yael Renert-Yuval
- Laboratory for Investigative Dermatology, The Rockefeller University, New York, New York
| | - Dante Dahabreh
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Grace W Kimmel
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Kelsey Auyeung
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Yeriel D Estrada
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Giselle Singer
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - James G Krueger
- Laboratory for Investigative Dermatology, The Rockefeller University, New York, New York
| | - Ana B Pavel
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Emma Guttman-Yassky
- Department of Dermatology and Laboratory of Inflammatory Skin Diseases, Icahn School of Medicine at Mount Sinai, New York, New York.
| |
Collapse
|
4
|
Hashim PW, Chima M, Kim HJ, Bares J, Yao CJ, Singer G, Chen T, Genece J, Baum D, Kimmel GW, Nia JK, Gagliotti M, Lebwohl MG. Crisaborole 2% ointment for the treatment of intertriginous, anogenital, and facial psoriasis: A double-blind, randomized, vehicle-controlled trial. J Am Acad Dermatol 2019; 82:360-365. [PMID: 31279028 DOI: 10.1016/j.jaad.2019.06.1288] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [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: 05/07/2019] [Revised: 06/24/2019] [Accepted: 06/28/2019] [Indexed: 11/16/2022]
Abstract
BACKGROUND Psoriasis of the intertriginous, anogenital, and facial regions remains a therapeutic challenge, with current algorithms lacking a topical agent that exhibits both high efficacy and minimal side effects. OBJECTIVE To assess the safety and efficacy of crisaborole 2% ointment-a nonsteroidal phosphodiesterase 4 inhibitor-in the treatment of intertriginous, anogenital, and facial psoriasis. METHODS A double-blind, randomized, vehicle-controlled trial was conducted in 21 participants. Participants were randomized 2:1 to receive 4 weeks of twice-daily treatment with either crisaborole 2% ointment (n = 14) or vehicle ointment (n = 7), followed by 4 weeks of open-label treatment with crisaborole 2% ointment. Disease severity was measured by using the Target Lesion Severity Scale (TLSS). RESULTS After 4 weeks, participants in the crisaborole group demonstrated 66% improvement compared with 9% in the vehicle group (P = .0011). Participants in the crisaborole group continued to experience improvement through the open-label phase, demonstrating 81% lesional improvement by week 8, with 71% of these participants achieving clinical clearance. There were no adverse events. LIMITATIONS The study was limited to a single tertiary care center and small sample size. CONCLUSION Treatment with crisaborole 2% ointment was well-tolerated and led to clinical improvement in participants with intertriginous, anogenital, or facial psoriasis.
Collapse
Affiliation(s)
- Peter W Hashim
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Margot Chima
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Hee J Kim
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jennifer Bares
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Christopher J Yao
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Giselle Singer
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Tinley Chen
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Jordan Genece
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Danielle Baum
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Grace W Kimmel
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - John K Nia
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Matthew Gagliotti
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York
| | - Mark G Lebwohl
- Department of Dermatology, The Icahn School of Medicine at Mount Sinai, New York, New York.
| |
Collapse
|
5
|
Abstract
Psoriasis is a chronic, common, inflammatory skin disease. The classic skin lesions can be described as sharply demarcated, scaly, erythematous plaques often found on the extensor surfaces. Several variants of psoriasis have also been described, including palmoplantar, pustular, erythrodermic, and guttate forms. Although psoriasis is usually diagnosed clinically, characteristic histologic findings include hyperkeratosis, parakeratosis, and acanthosis of the epidermis with dilated blood vessels and a lymphocytic infiltrate. Psoriasis is an immune-mediated disease, and although the etiology is not fully understood, genetic and environmental factors have been implicated. Importantly, psoriasis is associated with a number of systemic complications and comorbidities that have a high impact on affected patients.
Collapse
|
6
|
Boardman LA, Litzelman K, Seo S, Johnson RA, Vanderboom RJ, Kimmel GW, Cunningham JM, Gangnon RE, Engelman CD, Riegert-Johnson DL, Potter J, Haile R, Buchanan D, Jenkins MA, Rider DN, Thibodeau SN, Petersen GM, Skinner HG. The association of telomere length with colorectal cancer differs by the age of cancer onset. Clin Transl Gastroenterol 2014; 5:e52. [PMID: 24598784 PMCID: PMC3972691 DOI: 10.1038/ctg.2014.3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 01/03/2014] [Accepted: 01/08/2014] [Indexed: 12/30/2022] Open
Abstract
OBJECTIVES: Telomeres are nucleoprotein structures that cap the end of chromosomes and shorten with sequential cell divisions in normal aging. Short telomeres are also implicated in the incidence of many cancers, but the evidence is not conclusive for colorectal cancer (CRC). Therefore, the aim of this study was to assess the association of CRC and telomere length. METHODS: In this case–control study, we measured relative telomere length from peripheral blood leukocytes (PBLs) DNA with quantitative PCR in 598 CRC patients and 2,212 healthy controls. RESULTS: Multivariate analysis indicated that telomere length was associated with risk for CRC, and this association varied in an age-related manner; younger individuals (≤50 years of age) with longer telomeres (80–99 percentiles) had a 2–6 times higher risk of CRC, while older individuals (>50 years of age) with shortened telomeres (1–10 percentiles) had 2–12 times the risk for CRC. The risk for CRC varies with extremes in telomere length in an age-associated manner. CONCLUSIONS: Younger individuals with longer telomeres or older individuals with shorter telomeres are at higher risk for CRC. These findings indicate that the association of PBL telomere length varies according to the age of cancer onset and that CRC is likely associated with at minimum two different mechanisms of telomere dynamics.
Collapse
Affiliation(s)
- Lisa A Boardman
- Department of Gastroenterology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Kristin Litzelman
- Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Songwon Seo
- National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
| | - Ruth A Johnson
- Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | | | | | - Julie M Cunningham
- Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Ronald E Gangnon
- Department of Biostatistics and Medical Informatics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | - Corinne D Engelman
- Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| | | | - John Potter
- Public Health Sciences Division, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Robert Haile
- Department of Oncology, Stanford School of Medicine, The Stanford Cancer Institute, Stanford, California, USA
| | - Daniel Buchanan
- Queensland Institute of Medical Research, Clive Berghofer Cancer Research Centre, Brisbane, Queensland, Australia
| | - Mark A Jenkins
- Melbourne School of Population Health, The University of Melbourne, Melbourne, Victoria, Australia
| | - David N Rider
- Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Stephen N Thibodeau
- Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Gloria M Petersen
- Department of Health Sciences Research, Mayo Clinic College of Medicine, Rochester, Minnesota, USA
| | - Halcyon G Skinner
- Department of Population Health Sciences, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin, USA
| |
Collapse
|
7
|
Cunningham JM, Johnson RA, Litzelman K, Skinner HG, Seo S, Engelman CD, Vanderboom RJ, Kimmel GW, Gangnon RE, Riegert-Johnson DL, Baron JA, Potter JD, Haile R, Buchanan DD, Jenkins MA, Rider DN, Thibodeau SN, Petersen GM, Boardman LA. Telomere length varies by DNA extraction method: implications for epidemiologic research. Cancer Epidemiol Biomarkers Prev 2013; 22:2047-54. [PMID: 24019396 DOI: 10.1158/1055-9965.epi-13-0409] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [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] Open
Abstract
BACKGROUND Both shorter and longer telomeres in peripheral blood leukocyte (PBL) DNA have been associated with cancer risk. However, associations remain inconsistent across studies of the same cancer type. This study compares DNA preparation methods to determine telomere length from patients with colorectal cancer. METHODS We examined PBL relative telomere length (RTL) measured by quantitative PCR (qPCR) in 1,033 patients with colorectal cancer and 2,952 healthy controls. DNA was extracted with phenol/chloroform, PureGene, or QIAamp. RESULTS We observed differences in RTL depending on DNA extraction method (P < 0.001). Phenol/chloroform-extracted DNA had a mean RTL (T/S ratio) of 0.78 (range 0.01-6.54) compared with PureGene-extracted DNA (mean RTL of 0.75; range 0.00-12.33). DNA extracted by QIAamp yielded a mean RTL of 0.38 (range 0.02-3.69). We subsequently compared RTL measured by qPCR from an independent set of 20 colorectal cancer cases and 24 normal controls in PBL DNA extracted by each of the three extraction methods. The range of RTL measured by qPCR from QIAamp-extracted DNA (0.17-0.58) was less than from either PureGene or phenol/chloroform (ranges, 0.04-2.67 and 0.32-2.81, respectively). CONCLUSIONS RTL measured by qPCR from QIAamp-extracted DNA was less than from either PureGene or phenol/chloroform (P < 0.001). IMPACT Differences in DNA extraction method may contribute to the discrepancies between studies seeking to find an association between the risk of cancer or other diseases and RTL.
Collapse
Affiliation(s)
- Julie M Cunningham
- Authors' Affiliations: Departments of Laboratory Medicine and Pathology, Health Sciences Research, and Gastroenterology, Mayo Clinic College of Medicine; Mayo Clinic Cancer Center, Biomedical Statistics and Informatics, Mayo Clinic College of Medicine, Rochester, Minnesota; Departments of Population Health Sciences, and Biostatistics and Medical Informatics, School of Medicine and Public Health, University of Wisconsin, Madison, Wisconsin; University of Michigan, Ann Arbor, Michigan; Division of Gastroenterology, Mayo Clinic, Jacksonville, Florida; Biostatistics & Epidemiology, Geisel School of Medicine, Dartmouth University, Hanover, New Hampshire; Public Health Sciences Division, Cancer Prevention Program, Fred Hutchinson Cancer Research Center, Seattle, Washington; The Stanford Cancer Institute and Stanford School of Medicine, Department of Medicine, Stanford, California; Queensland Institute of Medical Research, Clive Berghofer Cancer Research Centre, Brisbane, Queensland; and Melbourne School of Population Health, The University of Melbourne, Parkville, Victoria, Australia
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Klein CJ, Kimmel GW, Pittock SJ, Engelstad JE, Cunningham JM, Wu Y, Dyck PJ. Large kindred evaluation of mitofusin 2 novel mutation, extremes of neurologic presentations, and preserved nerve mitochondria. ACTA ACUST UNITED AC 2011; 68:1295-302. [PMID: 21987543 DOI: 10.1001/archneurol.2011.225] [Citation(s) in RCA: 22] [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: 11/14/2022]
Abstract
BACKGROUND Mitofusin 2 (MFN2) is a mitochondrial membrane protein mediating mitochondrial fusion and function. Mutated MFN2 is responsible for Charcot-Marie-Tooth type 2A2. In small kindreds, specific MFN2 mutations have been reported to associate with severity of axonal neuropathy, optic atrophy, and involvement of the central nervous system. The results of the nerve biopsy specimens suggested that the mitochondria are structurally abnormal in patients with MFN2 mutations. OBJECTIVE To study a newly identified MFN2 mutation, Leu146Phe, and the associated phenotypes in a large kindred. PATIENTS An American kindred of Northern European and Cherokee American Indian descent. RESULTS Genetic analysis revealed a novel GTPase domain MFN2 mutation Leu146Phe that associated with clinical status of 15 studied persons (10 affected and 5 unaffected) and not found in 800 control persons. Clinical manifestations were markedly different. In 1 affected person, optic atrophy and brain magnetic resonance imaging abnormalities led to multiple sclerosis diagnosis and interferon β-1a treatment when neuropathy was initially unrecognized. Age of onset ranged from 1 to 45 years. In some affected family members, severe and rapid-onset motor sensory neuropathy led to early loss of ambulation, whereas other family members experienced minimal neuropathic sensory symptoms. Despite histologically significant loss of nerve fibers, the mitochondria were not distinguishable from diseased sural nerve biopsy specimens and healthy controls. CONCLUSIONS Novel MFN2 mutation Leu146Phe causes Charcot-Marie-Tooth type 2A2. Intrafamilial clinical phenotype variability is emphasized and has important implications in genetic counseling. The clinical phenotype may mimic multiple sclerosis when optic atrophy and the characteristic brain lesions of MFN2 on magnetic resonance imaging are present and neuropathy is mild or unrecognized. The predicted molecular pathogenesis may occur without evident histological abnormalities of mitochondria in nerve.
Collapse
Affiliation(s)
- Christopher J Klein
- Division of Neuroimmunology, Department of Medical Genetics, Mayo Clinic, Rochester, MN 55905, USA.
| | | | | | | | | | | | | |
Collapse
|