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2830 citation(s) found for "Js, Park".

The OncoArray Consortium: A Network for Understanding the Genetic Architecture of Common Cancers
Wang, Zhaoming , Schumacher, Fredrick R. , Gayther, Simon A. , Casey, Graham , Sellers, Thomas A. , Gruber, Stephen B., Dunning, Alison M. , Michailidou, Kyriaki , Fachal, Laura , Doheny, Kimberly F. , Li, Yafang , Xiao, Xiangjun , Romm, Jane, Pugh, Elizabeth, Coetzee, Gerhard A. , Hazelett, Dennis J. , Bojesen, Stig E. , Caga-Anan, Charlisse , Haiman, Christopher A. , Kamal, Ahsan , Luccarini, Craig , Tessier, Daniel C., Vincent, Daniel , Bacot, François, Berg, David Van Den , Nelson, Stefanie A. , Demetriades, Stephen, Goldgar, David E., Forman, Judith L., Conti, David V. , Bickeböller, Heike , Risch, Angela , Waldenberger, Mélanie , Brüske‐Hohlfeld, Irene, Hicks, Belynda , McGuffog, Lesley, Kuchenbaecker, Karoline , Soucy, Penny, Manz, Judith, Cunningham, Julie M. , Butterbach, Katja, Kote‐Jarai, Zsofia , Kraft, Peter , Lindström, Sara , Adams, Marcia, McKay, James , Phelan, Catherine M., Benlloch, Sara, Kelemen, Linda E., Brennan, Paul , Riggan, Marjorie J. , O’Mara, Tracy A. , Shen, Hongbing , Shi, Yongyong , Thompson, Deborah J. , Goodman, Marc T. , Nielsen, Sune F. , LaBoissière, Sylvie, Schmit, Stephanie L. , Shelford, Tameka, Edlund, Christopher K., Taylor, Jack A. , Field, John K. , Park, Sue K. , Offit, Kenneth , Thomassen, Mads , Schmutzler, Rita K., Ottini, Laura , Hung, Rayjean J., Olama, Ali Amin Al , Peters, Ulrike , Eeles, Rosalind A. , Seldin, Michael F., Gillanders, Elizabeth M. , Seminara, Daniela, Antoniou, Antonis C. , Chenevix‐Trench, Georgia , Simard, Jacques , Easton, Douglas F. , Durocher, Francine , Hung, Rayjean J. , Amos, Christopher I. , Dennis, Joe , Byun, Jinyoung , Hunter, David J. , Spurdle, Amanda B. , Couch, Fergus J. , Giles, Graham G. , Ling, Hua , Lee, Andrew , FitzGerald, Liesel M. , Berchuck, Andrew , Marchini, Jonathan , Pharoah, Paul D.P. , Chanock, Stephen Jacob , Hazelett, Dennis J , Eeles, Rosalind A , Van Den Berg, David J , Hung, Rayjean J , Wang, Zhaoming , O'Mara, Tracy A , Field, John K , Dunning, Alison M , Michailidou, Kyriaki , Taylor, Jack A , Kraft, Peter , Simard, Jacques , Chenevix-Trench, Georgia , Ottini, Laura , Conti, David V , Bojesen, Stig E , Risch, Angela , Bickeböller, Heike , Shen, Hongbing , Goodman, Marc T , Fachal, Laura

Cancer Epidemiology, Biomarkers & Prevention | October 3, 2016 | Volume: 26 | Issue: 1 | Pages: 126-135

10.1158/1055-9965.epi-16-0106 | PMID 27697780 Get It

Abstract Background: Common cancers develop through a multistep process often including inherited susceptibility. Collaboration among multiple institutions, and funding from multiple sources, has allowed the development of an inexpensive genotyping microarray, the OncoArray. The array includes a genome-wide backbone, comprising 230,000 SNPs tagging most common genetic variants, together with dense mapping of known susceptibility regions, rare variants from sequencing experiments, pharmacogenetic markers, and cancer-related traits. Methods: The OncoArray can be genotyped using a novel technology developed by Illumina to facilitate efficient genotyping. The consortium developed standard approaches for selecting SNPs for study, for quality control of markers, and for ancestry analysis. The array was genotyped at selected sites and with prespecified replicate samples to permit evaluation of genotyping accuracy among centers and by ethnic background. Results: The OncoArray consortium genotyped 447,705 samples. A total of 494,763 SNPs passed quality control steps with a sample success rate of 97% of the samples. Participating sites performed ancestry analysis using a common set of markers and a scoring algorithm based on principal components analysis. Conclusions: Results from these analyses will enable researchers to identify new susceptibility loci, perform fine-mapping of new or known loci associated with either single or multiple cancers, assess the degree of overlap in cancer causation and pleiotropic effects of loci that have been identified for disease-specific risk, and jointly model genetic, environmental, and lifestyle-related exposures. Impact: Ongoing analyses will shed light on etiology and risk assessment for many types of cancer. Cancer Epidemiol Biomarkers Prev; 26(1); 126–35. ©2016 AACR.
A Case of Simultaneous Benign Metastasizing Leiomyomas and Disseminated Peritoneal Leiomyomatosis Following Endoscopic Power Morcellation for Uterine Disease
Park, Beau Y., Leslie, Kevin O., Vaszar, Laszlo T. , Cornella, Jeffrey L. , Chen, Longwen

Female Pelvic Medicine & Reconstructive Surgery | September 30, 2016 | Volume: 23 | Issue: 1 | Pages: e1-e3

10.1097/spv.0000000000000342 | PMID 27748666 Get It

Abstract Extrauterine spread of leiomyomas is rare and most commonly occurs in the lungs. We present a case of simultaneous metastatic leiomyomatosis to the lungs and peritoneal cavity following laparoscopic myomectomy with power morcellation. The patient presented to our institution for further management where she underwent a robotically assisted hysterectomy with bilateral salpingo-oophorectomy. Leiomyomatous implants measuring up to 2.4 cm were resected from bowel mesentery and bladder peritoneum. Subsequent serial computed tomography imaging confirmed stable pulmonary nodules without new intraperitoneal lesions. Increasing number of cases involving extrauterine spread of leiomyomas has been reported with the introduction of power morcellation. The exact pathogenesis is unknown but is likely multifactorial. We emphasize that although the incidence of spread of benign disease is low, it is important to recognize this phenomenon as we will likely continue to encounter similar cases in the coming years.
No Evidence That Genetic Variation in the Myeloid-Derived Suppressor Cell Pathway Influences Ovarian Cancer Survival
Sucheston‐Campbell, Lara, Cannioto, Rikki , Clay‐Gilmour, Alyssa , Etter, John Lewis , Eng, Kevin H., Liu, Song , Battaglia, Sebastiano , Szender, J. Brian, Minlikeeva, Albina N. , Joseph, Janine M. , Mayor, Paul , Abrams, Scott I. , Wallace, Paul K. , Soh, Kah Teong , Zsíros, Emese , Beckmann, Matthias W. , Bruegl, Amanda , Campbell, Ian , Campbell, Shawn, Chenevix‐Trench, Georgia , Diergaarde, Brenda , Doerk, Thilo, Eccles, Diana , Engelholm, Svend Aage, Fasching, Peter A. , Gayther, Simon A. , Goodman, Marc T. , Harter, Philipp , Hein, Alexander , Heitz, Florian , Hillemmanns, Peter, Høgdall, Claus , Høgdall, Estrid , Huzarski, Tomasz , Jensen, Allan , Johnatty, Sharon E. , Jung, Audrey , Klapdor, Reudiger, Kluz, Tomasz , Konopka, Bożena , Kupryjańczyk, Jolanta , Lambrechts, Diether , Lester, Jenny, Lubiński, Jan , Levine, Douglas A. , Lundvall, Lene, McGuire, Valerie , McNeish, Iain A. , Menon, Usha , Ness, Roberta B., Oršulić, Sandra , Pearce, Celeste Leigh, Ramus, Susan J. , Rothstein, Joseph H. , Rossing, Mary Anne, Rübner, Matthias, Schildkraut, Joellen M. , Schmalfeldt, Barbara , Schwaab, Ira, Sieh, Weiva , Sobiczewski, Piotr , Song, Honglin , Terry, Kathryn L. , Nieuwenhuysen, Els Van , Vanderstichele, Adriaan , Vergote, Ignace , Walsh, Christine , Webb, Penelope M. , Wentzensen, Nicolas , Whittemore, Alice S. , Wu, Anna H. , Odunsi, Kunle , Chang‐Claude, Jenny , Goode, Ellen L. , Moysich, Kirsten B. , Dörk, Thilo , Bowtell, David D.L. , Lambrechts, Diether , Clay, Alyssa I, Hu, Qiang , Segal, Brahm H. , Anton‐Culver, Hoda , Bandera, Elisa V. , Berchuck, Andrew , Bjørge, Line , Cramer, Daniel W. , Dansonka‐Mieszkowska, Agnieszka , Dao, Fanny , Doherty, Jennifer A. , Bois, Andreas du , Gentry‐Maharaj, Aleksandra , Glasspool, Rosalind , Gronwald, Jacek , Karlan, Beth Y. , Kjær, Susanne K. , Modugno, Francesmary , Paul, James , Pejovic, Tanja B. , Pharoah, Paul D.P. , Siddiqui, Nadeem , Ziogas, Argyrios , Dörk, Thilo , Lambrechts, Diether , McNeish, Iain A , Ramus, Susan J , Vanderstichele, Adriaan , Webb, Penelope M , Hein, Alexander , Jensen, Allan , Eccles, Diana , Menon, Usha , Moysich, Kirsten , Campbell, Ian G , Heitz, Florian , Kupryjanczyk, Jolanta , Lambrechts, Diether , Sieh, Weiva , Chenevix-Trench, Georgia , Høgdall, Estrid , Høgdall, Claus K , Huzarski, Tomasz , Jung, Audrey Y , Bowtell, David D , Diergaarde, Brenda , Lubinski, Jan , Kluz, Tomasz , Goodman, Marc T

Cancer Epidemiology, Biomarkers & Prevention | September 28, 2016 | Volume: 26 | Issue: 3 | Pages: 420-424

10.1158/1055-9965.epi-16-0631 | PMID 27677730 Get It

Abstract Background: The precise mechanism by which the immune system is adversely affected in cancer patients remains poorly understood, but the accumulation of immunosuppressive/protumorigenic myeloid-derived suppressor cells (MDSCs) is thought to be a prominent mechanism contributing to immunologic tolerance of malignant cells in epithelial ovarian cancer (EOC). To this end, we hypothesized genetic variation in MDSC pathway genes would be associated with survival after EOC diagnoses. Methods: We measured the hazard of death due to EOC within 10 years of diagnosis, overall and by invasive subtype, attributable to SNPs in 24 genes relevant in the MDSC pathway in 10,751 women diagnosed with invasive EOC. Versatile Gene-based Association Study and the admixture likelihood method were used to test gene and pathway associations with survival. Results: We did not identify individual SNPs that were significantly associated with survival after correction for multiple testing (P < 3.5 × 10−5), nor did we identify significant associations between the MDSC pathway overall, or the 24 individual genes and EOC survival. Conclusions: In this well-powered analysis, we observed no evidence that inherited variations in MDSC-associated SNPs, individual genes, or the collective genetic pathway contributed to EOC survival outcomes. Impact: Common inherited variation in genes relevant to MDSCs was not associated with survival in women diagnosed with invasive EOC. Cancer Epidemiol Biomarkers Prev; 26(3); 420–4. ©2016 AACR.
Regional Colonic Transit Pattern Does Not Conclusively Identify Evacuation Disorders in Constipated Patients with Delayed Colonic Transit
Burton, Duane D. , Busciglio, Irene, Eckert, Deborah J., Camilleri, Michael , Burton, Duane, Eckert, Deborah, Park, Seon‐Young

Journal of Neurogastroenterology and Motility | September 26, 2016 | Volume: 23 | Issue: 1 | Pages: 92-100

10.5056/jnm16066 | PMID 27667753 Get It

Exploring hypotheses and rationale for causes of infantile colic
Camilleri, M., Park, S.‐Y., Scarpato, Elena , Staiano, Annamaria

Neurogastroenterology & Motility | September 20, 2016 | Volume: 29 | Issue: 2 | Pages: No page available

10.1111/nmo.12943 | PMID 27647578 Get It

AbstractBackgroundInfantile colic is a frequent problem in neonates and infants. This review addresses current management including the results for nutrient modifications; soy‐based formulas; and prebiotics, probiotics, and synbiotics.PurposeGiven the evidence that there is still an unmet clinical need, as current treatments are incompletely efficacious, we have examined the evidence around three hypothetical mechanisms that could potentially be involved in etiopathogenesis of infantile colic: immaturity of bile acid mechanisms that alter intraluminal and absorptive mechanisms, immaturity in motility and alterations in the microbiome. Understanding these potential mechanisms may lead to the introduction of diagnostic procedures that should enhance the selection or individualization of therapy for infantile colic.
Alcohol consumption and prostate cancer incidence and progression: A Mendelian randomisation study
Brunner, Clair , Davies, Neil M , Martin, Richard M. , Eeles, Rosalind A. , Easton, Doug , Olama, Ali Amin Al , Benlloch, Sara, Muir, Kenneth , Grönberg, Henrik , Haiman, Christopher A. , Schleutker, Johanna , Nordestgaard, Børge G. , Travis, Ruth C. , Neal, David E. , Donovan, Jenny , Hamdy, Freddie C. , Pashayan, Nora , Stanford, Janet L. , Blot, William J. , Thibodeau, Stephen N. , Maier, Christiane, Kibel, Adam S. , Brenner, Hermann , Kaneva, Radka , Batra, Jyotsna , Teixeira, Manuel R. , Pandha, Hardev , Zuccolo, Luisa , Thibodeau, Stephen, Easton, Douglas F. , Kote‐Jarai, Zsofia , Giles, Graham G. , Wiklund, Fredrik E. , Khaw, Kay‐Tee , Cybulski, Cezary , Cannon‐Albright, Lisa , Park, Jong Y. , Teixeira, Manuel R , Eeles, Rosalind A , Donovan, Jenny L , Muir, Kenneth , Schleutker, Johanna , Travis, Ruth C , Pashayan, Nora , Brenner, Hermann , Martin, Richard M , Batra, Jyotsna

International Journal of Cancer | September 19, 2016 | Volume: 140 | Issue: 1 | Pages: 75-85

10.1002/ijc.30436 | PMID 27643404 Get It

Prostate cancer is the most common cancer in men in developed countries, and is a target for risk reduction strategies. The effects of alcohol consumption on prostate cancer incidence and survival remain unclear, potentially due to methodological limitations of observational studies. In this study, we investigated the associations of genetic variants in alcohol‐metabolising genes with prostate cancer incidence and survival. We analysed data from 23,868 men with prostate cancer and 23,051 controls from 25 studies within the international PRACTICAL Consortium. Study‐specific associations of 68 single nucleotide polymorphisms (SNPs) in 8 alcohol‐metabolising genes (Alcohol Dehydrogenases (ADHs) and Aldehyde Dehydrogenases (ALDHs)) with prostate cancer diagnosis and prostate cancer‐specific mortality, by grade, were assessed using logistic and Cox regression models, respectively. The data across the 25 studies were meta‐analysed using fixed‐effect and random‐effects models. We found little evidence that variants in alcohol metabolising genes were associated with prostate cancer diagnosis. Four variants in two genes exceeded the multiple testing threshold for associations with prostate cancer mortality in fixed‐effect meta‐analyses. SNPs within ALDH1A2 associated with prostate cancer mortality were rs1441817 (fixed effects hazard ratio, HRfixed = 0.78; 95% confidence interval (95%CI):0.66,0.91; p values = 0.002); rs12910509, HRfixed = 0.76; 95%CI:0.64,0.91; p values = 0.003); and rs8041922 (HRfixed = 0.76; 95%CI:0.64,0.91; p values = 0.002). These SNPs were in linkage disequilibrium with each other. In ALDH1B1, rs10973794 (HRfixed = 1.43; 95%CI:1.14,1.79; p values = 0.002) was associated with prostate cancer mortality in men with low‐grade prostate cancer. These results suggest that alcohol consumption is unlikely to affect prostate cancer incidence, but it may influence disease progression.
Three new pancreatic cancer susceptibility signals identified on chromosomes 1q32.1, 5p15.33 and 8q24.21
Wang, Zhaoming , Obazee, Ofure , Jia, Jinping , Childs, Erica J., Hoskins, Jason W. , Figlioli, Gisella , Collins, Irene , Chung, Charles C., Hautman, Christopher, Arslan, Alan A. , Bracci, Paige M. , Buring, Julie E. , Gallinger, Steven , Goodman, Gary E. , Goodman, Phyllis J. , Kamineni, Aruna , Kolonel, Laurence N. , Kulke, Matthew H. , Malats, Núria , Olson, Sara H. , Sesso, Howard D. , Visvanathan, Kala , Zheng, Wei , Abnet, Christian C. , Andreotti, Gabriella , Bueno-de-Mesquita, H. Bas, Basso, Daniela , Berndt, Sonja I. , Brenner, Hermann , Burdette, Laurie , Campa, Daniele , Caporaso, Neil E. , Capurso, Gabriele , Cavestro, Giulia Martina , Costello, Eithne , Elena, Joanne W. , Boggi, Ugo , Gaziano, J. Michael , Giovannucci, Edward L. , Gross, Myron D., Haiman, Christopher A. , Hassan, Manal M. , Helzlsouer, Kathy J., Hu, Nan , Hunter, David J., Iskierka‐Jazdzewska, Elżbieta , Jenab, Mazda , Klein, Eric A. , Krogh, Vittorio , Kupčinskas, Juozas , Kurtz, Robert C. , Landi, Maria Teresa , Mambrini, Andrea , Neale, Rachel Ε. , Oberg, Ann L. , Patel, Alpa V. , Peeters, Petra H., Peters, Ulrike , Pezzilli, Raffaele , Porta, Miquel , Purdue, Mark P. , Quirós, J. Ramón , Ríboli, Elio , Rothman, Nathaniel , Scarpa, Aldo , Scélo, Ghislaine , Strobel, Oliver , Małecka‐Panas, Ewa , Tavano, Francesca , Travis, Ruth C. , Thornquist, Mark, Tjønneland, Anne , Trichopoulos, Dimitrios, Vashist, Yogesh K. , Vodička, Pavel , Wactawski‐Wende, Jean , Wentzensen, Nicolas , Yu, Kai , Zeleniuch‐Jacquotte, Anne , Jacobs, Eric J. , Li, Donghui , Fuchs, Charles S. , Hoover, Robert N. , Hartge, Patricia, Petersen, Gloria M. , Stolzenberg-Solomon, Rachael S., Wolpin, Brian M. , Kraft, Peter , Canzian, Federico , Ámundadóttir, Laufey T. , Zhang, Mingfeng , Mocci, Evelina , Freeman, Laura E. Beane , Duell, Eric J. , Giles, Graham G. , White, Emily , Albanes, Demetrius , Brais, Lauren K , Boutron‐Ruault, Marie‐Christine , Bijlsma, Maarten F. , Cotterchio, Michelle , Gazouli, Maria , Goggins, Michael , Kaaks, Rudolf , Key, Tim , Khaw, Kay‐Tee , Kogevinas, Manolis , Kupcinskas, Juozas , Landi, Stefano , Marchand, Loı̈c Le , Männistö, Satu , Milne, Roger L. , Panico, Salvatore , Shu, Xiao‐Ou , Silverman, Debra T. , Souček, Pavel , Sund, Malin , Taylor, Philip R. , Tobias, Geoffrey S. , Yu, Kai , Kooperberg, Charles , Risch, Harvey A. , Chanock, Stephen Jacob , Klein, Alison P. , Amundadottir, Laufey , Malats, Nuria , Arslan, Alan A , Canzian, Federico , Tjønneland, Anne , Wactawski-Wende, Jean , Travis, Ruth C , Wang, Zhaoming , Abnet, Christian C , Visvanathan, Kala , Klein, Eric A , Brenner, Hermann , Strobel, Oliver , Jenab, Mazda , Kraft, Peter , Zheng, Wei , Iskierka-Jazdzewska, Elżbieta , Riboli, Elio , Vodicka, Pavel , Neale, Rachel E , Porta, Miquel , Zeleniuch-Jacquotte, Anne , Hoskins, Jason W , Tavano, Francesca

Oncotarget | September 16, 2016 | Volume: 7 | Issue: 41 | Pages: 66328-66343

10.18632/oncotarget.11041 | PMID 27579533 Get It

Late acute graft-versus-host disease: a prospective analysis of clinical outcomes and circulating angiogenic factors
Holtan, Shernan G. , Khera, Nandita , Levine, John E. , Chai, Xiaoyu , Storer, Barry E. , Liu, Hien , Inamoto, Yoshihiro , Mayer, Sebastian , Arora, Mukta , Palmer, Jeanne , Lukez, Alexander , Arai, Sally , Lazaryan, Aleksandr , Newell, Laura F. , Krupski, Christa , Jagasia, Madan , Pusic, Iskra , Wood, William A. , Renteria, Anne S. , Yanik, Gregory A. , Ayuk, Francis , Holler, Ernst , Watanaboonyongcharoen, Phandee , Efebera, Yvonne A. , Ferrara, James L.M. , Weisdorf, Daniel J. , Lee, Stephanie J. , Pidala, Joseph, Chen, George L. , Flowers, Mary E.D. , Cutler, Corey S. , Hogan, William J. , Hexner, Elizabeth O. , Panoskaltsis‐Mortari, Angela , Weisdorf, Dan , Levine, John E , Holtan, Shernan , Lee, Stephanie J , Wood, William A

Blood | September 14, 2016 | Volume: 128 | Issue: 19 | Pages: 2350-2358

10.1182/blood-2015-09-669846 | PMID 27625357 Get It

Key Points Under current treatment approaches, patients with LA GVHD have poor overall and failure-free survival. Levels of AREG are elevated in LA GVHD, and the AREG/EGF ratio is predictive of overall survival and nonrelapse mortality in LA GVHD.
Efficacy of (S)-lacosamide in preclinical models of cephalic pain
Moutal, Aubin , Eyde, Nathan, Telemi, Edwin, Xie, Jennifer Y. , Park, Ki Duk , Dodick, David W. , Porreca, Frank , Khanna, Rajesh

PAIN Reports | September 9, 2016 | Volume: 1 | Issue: 1 | Pages: e565

10.1097/pr9.0000000000000565 | PMID 27917413 Get It

AbstractMigraine is one of the world's most common neurological disorders. Current acute migraine treatments have suboptimal efficacy, and new therapeutic options are needed. Approaches targeting calcitonin gene related peptide (CGRP) signaling are clinically effective, but small molecule antagonists have not been advanced because of toxicity. In this study, we explored the axonal growth/specification collapsin response mediator protein 2 (CRMP2) as a novel “druggable” target for inhibiting CGRP release and for potential relevance for treatment of migraine pain. Collapsin response mediator protein 2 has been demonstrated to regulate N-type voltage-gated Ca2+channel activity and Ca2+-dependent CGRP release in sensory neurons. The coexpression of CRMP2 with N-type voltage-gated Ca2+channel and CGRP in trigeminal ganglia (TGs) sensory neurons suggested the possibility of a novel approach to regulate CGRP release in the trigeminal system. Screening protocols surprisingly revealed that (S)-lacosamide ((S)-LCM), an inactive analog of the clinically approved small molecule antiepileptic drug (R)-lacosamide (Vimpat), inhibited CRMP2 phosphorylation by cyclin-dependent kinase 5 in rat TG slices and decreased depolarization-evoked Ca2+influx in TG cells in culture. (S)-LCM significantly blocked capsaicin-evoked CGRP release from dural nerve terminals in the rat in ex vivo cranial cup preparation. Additionally, cephalic and extracephalic cutaneous allodynia induced in rats by activation of dural nociceptors with a cocktail of inflammatory mediators, was inhibited by oral administration of (S)-LCM. The confirmation of CRMP2 as an upstream mediator of CGRP release, together with the brain penetrance of this molecule suggests (S)-LCM as a potential therapy for acute migraine.
Dysregulation of protein phosphatase 2A in parkinson disease and dementia with lewy bodies
Park, Hyejin , Lee, Kang‐Woo, Park, Eun Su , Oh, Stephanie , Yan, Run , Zhang, Jie , Beach, Thomas G. , Voronkov, Michael , Braithwaite, Steven P. , Stock, Jeffry B. , Adler, Charles H. , Mouradian, M. Maral

Annals of Clinical and Translational Neurology | September 8, 2016 | Volume: 3 | Issue: 10 | Pages: 769-780

10.1002/acn3.337 | PMID 27752512 Get It

AbstractObjectiveProtein phosphatase 2A (PP2A) is a heterotrimeric holoenzyme composed of a catalytic C subunit, a structural A subunit, and one of several regulatory B subunits that confer substrate specificity. The assembly and activity of PP2A are regulated by reversible methylation of the C subunit. α‐Synuclein, which aggregates in Parkinson disease (PD) and dementia with Lewy bodies (DLB), is phosphorylated at Ser129, and PP2A containing a B55α subunit is a major phospho‐Ser129 phosphatase. The objective of this study was to investigate PP2A in α‐synucleinopathies.MethodsWe compared the state of PP2A methylation, as well as the expression of its methylating enzyme, leucine carboxyl methyltransferase (LCMT‐1), and demethylating enzyme, protein phosphatase methylesterase (PME‐1), in postmortem brains from PD and DLB cases as well as age‐matched Controls. Immunohistochemical studies and quantitative image analysis were employed.ResultsLCMT‐1 was significantly reduced in the substantia nigra (SN) and frontal cortex in both PD and DLB. PME‐1, on the other hand, was elevated in the PD SN. In concert with these changes, the ratio of methylated PP2A to demethylated PP2A was markedly decreased in PD and DLB brains in both SN and frontal cortex. No changes in total PP2A or total B55α subunit were detected.InterpretationThese findings support the hypothesis that PP2A dysregulation in α‐synucleinopathies may contribute to the accumulation of hyperphosphorylated α‐synuclein and to the disease process, raising the possibility that pharmacological means to enhance PP2A phosphatase activity may be a useful disease‐modifying therapeutic approach.