Browsing by Subject "DNA METHYLATION"

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  • Kahila, Hanna; Marjonen, Heidi; Auvinen, Pauliina; Avela, Kristiina; Riikonen, Raili; Kaminen-Ahola, Nina (2020)
    Abstract Background A pair of dizygotic twins discordantly affected by heavy prenatal alcohol exposure (PAE) was reported previously by Riikonen, suggesting the role of genetic risk or protective factors in the etiology of alcohol-induced developmental disorders. Now, we have re-examined these 25-year-old twins and explored genetic origin of the phenotypic discordancy reminiscent with fetal alcohol syndrome (FAS). Furthermore, we explored alterations in DNA methylation profile of imprinting control region at growth-related insulin-like growth factor 2 (IGF2)/H19 locus in twins' white blood cells (WBC), which have been associated earlier with alcohol-induced genotype-specific changes in placental tissue. Methods Microarray-based comparative genomic hybridization (aCGH) was used to detect potential submicroscopic chromosomal abnormalities, and developmental as well as phenotypic information about twins were collected. Traditional bisulfite sequencing was used for DNA methylation analysis. Results Microarray-based comparative genomic hybridization revealed a microdeletion 18q12.3-q21.1. in affected twin, residing in a known 18q deletion syndrome region. This syndrome has been associated with growth restriction, developmental delay or intellectual deficiency, and abnormal facial features in previous studies, and thus likely explains the phenotypic discordancy between the twins. We did not observe association between WBCs? DNA methylation profile and PAE, but interestingly, a trend of decreased DNA methylation at the imprinting control region was seen in the twin with prenatal growth retardation at birth. Conclusions The microdeletion emphasizes the importance of adequate chromosomal testing in examining the etiology of complex alcohol-induced developmental disorders. Furthermore, the genotype-specific decreased DNA methylation at the IGF2/H19 locus cannot be considered as a biological mark for PAE in adult WBCs.
  • Loukola, Anu; Buchwald, Jadwiga; Gupta, Richa; Palviainen, Teemu; Hallfors, Jenni; Tikkanen, Emmi; Korhonen, Tellervo; Ollikainen, Miina; Sarin, Antti-Pekka; Ripatti, Samuli; Lehtimaki, Terho; Raitakari, Olli; Salomaa, Veikko; Rose, Richard J.; Tyndale, Rachel F.; Kaprio, Jaakko (2015)
    Individuals with fast nicotine metabolism typically smoke more and thus have a greater risk for smoking-induced diseases. Further, the efficacy of smoking cessation pharmacotherapy is dependent on the rate of nicotine metabolism. Our objective was to use nicotine metabolite ratio (NMR), an established biomarker of nicotine metabolism rate, in a genome-wide association study (GWAS) to identify novel genetic variants influencing nicotine metabolism. A heritability estimate of 0.81 (95% CI 0.70-0.88) was obtained for NMR using monozygotic and dizygotic twins of the FinnTwin cohort. We performed a GWAS in cotinine-verified current smokers of three Finnish cohorts (FinnTwin, Young Finns Study, FIN-RISK2007), followed by a meta-analysis of 1518 subjects, and annotated the genome-wide significant SNPs with methylation quantitative loci (meQTL) analyses. We detected association on 19q13 with 719 SNPs exceeding genome-wide significance within a 4.2 Mb region. The strongest evidence for association emerged for CYP2A6 (min p = 5.77E-86, in intron 4), the main metabolic enzyme for nicotine. Other interesting genes with genome-wide significant signals included CYP2B6, CYP2A7, EGLN2, and NUMBL. Conditional analyses revealed three independent signals on 19q13, all located within or in the immediate vicinity of CYP2A6. A genetic risk score constructed using the independent signals showed association with smoking quantity (p = 0.0019) in two independent Finnish samples. Our meQTL results showed that methylation values of 16 CpG sites within the region are affected by genotypes of the genome-wide significant SNPs, and according to causal inference test, for some of the SNPs the effect on NMR is mediated through methylation. To our knowledge, this is the first GWAS on NMR. Our results enclose three independent novel signals on 19q13.2. The detected CYP2A6 variants explain a strikingly large fraction of variance (up to 31%) in NMR in these study samples. Further, we provide evidence for plausible epigenetic mechanisms influencing NMR.
  • Hebbar, Prashantha; Abubaker, Jehad Ahmed; Abu-Farha, Mohamed; Tuomilehto, Jaakko; Al-Mulla, Fahd; Thanaraj, Thangavel Alphonse (2019)
    Despite dedicated nation-wide efforts to raise awareness against the harmful effects of fast-food consumption and sedentary lifestyle, the Arab population continues to struggle with an increased risk for metabolic disorders. Unlike the European population, the Arab population lacks well-established genetic risk determinants for metabolic disorders, and the transferability of established risk loci to this population has not been satisfactorily demonstrated. The most recent findings have identified over 240 genetic risk loci (with similar to 400 independent association signals) for type 2 diabetes, but thus far only 25 risk loci (ADAMTS9, ALX4, BCL11A, CDKAL1, CDKN2A/B, COL8A1, DUSP9, FTO, GCK, GNPDA2, HMG20A, HNF1A, HNF1B, HNF4A, IGF2BP2, JAZF1, KCNJ11 , KCNQ1, MC4R, PPAR gamma, SLC30A8, TCF7L2, TFAP2B, TP53INP1, and WFS1) have been replicated in Arab populations. To our knowledge, large-scale population- or family-based association studies are non-existent in this region. Recently, we conducted genome-wide association studies on Arab individuals from Kuwait to delineate the genetic determinants for quantitative traits associated with anthropometry, lipid profile, insulin resistance, and blood pressure levels. Although these studies led to the identification of novel recessive variants, they failed to reproduce the established loci. However, they provided insights into the genetic architecture of the population, the applicability of genetic models based on recessive mode of inheritance, the presence of genetic signatures of inbreeding due to the practice of consanguinity, and the pleiotropic effects of rare disorders on complex metabolic disorders. This perspective presents analysis strategies and study designs for identifying genetic risk variants associated with diabetes and related traits in Arab populations.
  • Wehkalampi, Karoliina; Muurinen, Mari; Wirta, Sara Bruce; Hannula-Jouppi, Katariina; Hovi, Petteri; Järvenpää, Anna-Liisa; Eriksson, Johan G.; Andersson, Sture; Kere, Juha; Kajantie, Eero (2013)
  • Knight, Anna K.; Craig, Jeffrey M.; Theda, Christiane; Baekvad-Hansen, Marie; Bybjerg-Grauholm, Jonas; Hansen, Christine S.; Hollegaard, Mads V.; Hougaard, David M.; Mortensen, Preben B.; Weinsheimer, Shantel M.; Werge, Thomas M.; Brennan, Patricia A.; Cubells, Joseph F.; Newport, D. Jeffrey; Stowe, Zachary N.; Cheong, Jeanie L. Y.; Dalach, Philippa; Doyle, Lex W.; Loke, Yuk J.; Baccarelli, Andrea A.; Just, Allan C.; Wright, Robert O.; Tellez-Rojo, Mara M.; Svensson, Katherine; Trevisi, Letizia; Kennedy, Elizabeth M.; Binder, Elisabeth B.; Iurato, Stella; Räikkönen, Katri; Lahti, Jari M. T.; Pesonen, Anu-Katriina; Kajantie, Eero; Villa, Pia M.; Laivuori, Hannele; Hämäläinen, Esa; Park, Hea Jin; Bailey, Lynn B.; Parets, Sasha E.; Kilaru, Varun; Menon, Ramkumar; Horvath, Steve; Bush, Nicole R.; LeWinn, Kaja Z.; Tylavsky, Frances A.; Conneely, Karen N.; Smith, Alicia K. (2016)
    Background: Gestational age is often used as a proxy for developmental maturity by clinicians and researchers alike. DNA methylation has previously been shown to be associated with age and has been used to accurately estimate chronological age in children and adults. In the current study, we examine whether DNA methylation in cord blood can be used to estimate gestational age at birth. Results: We find that gestational age can be accurately estimated from DNA methylation of neonatal cord blood and blood spot samples. We calculate a DNA methylation gestational age using 148 CpG sites selected through elastic net regression in six training datasets. We evaluate predictive accuracy in nine testing datasets and find that the accuracy of the DNA methylation gestational age is consistent with that of gestational age estimates based on established methods, such as ultrasound. We also find that an increased DNA methylation gestational age relative to clinical gestational age is associated with birthweight independent of gestational age, sex, and ancestry. Conclusions: DNA methylation can be used to accurately estimate gestational age at or near birth and may provide additional information relevant to developmental stage. Further studies of this predictor are warranted to determine its utility in clinical settings and for research purposes. When clinical estimates are available this measure may increase accuracy in the testing of hypotheses related to developmental age and other early life circumstances.
  • Nuotio, Marja-Liisa; Pervjakova, Natalia; Joensuu, Anni; Karhunen, Ville; Hiekkalinna, Tero; Milani, Lili; Kettunen, Johannes; Järvelin, Marjo-Riitta; Jousilahti, Pekka; Metspalu, Andres; Salomaa, Veikko; Kristiansson, Kati; Perola, Markus (2020)
    The role of metabolic syndrome (MetS) as a preceding metabolic state for type 2 diabetes and cardiovascular disease is widely recognised. To accumulate knowledge of the pathological mechanisms behind the condition at the methylation level, we conducted an epigenome-wide association study (EWAS) of MetS and its components, testing 1187 individuals of European ancestry for approximately 470 000 methylation sites throughout the genome. Methylation site cg19693031 in gene TXNIP -previously associated with type 2 diabetes, glucose and lipid metabolism, associated with fasting glucose level (P=1.80x10(-8)). Cg06500161 in gene ABCG1 associated both with serum triglycerides (P=5.36x10(-9)) and waist circumference (P=5.21x10(-9)). The previously identified type 2 diabetes-associated locus cg08309687 in chromosome 21 associated with waist circumference for the first time (P=2.24x10(-7)). Furthermore, a novel HDL association with cg17901584 in chromosome 1 was identified (P=7.81x10(-8)). Our study supports previous genetic studies of MetS, finding that lipid metabolism plays a key role in pathology of the syndrome. We provide evidence regarding a close interplay with glucose metabolism. Finally, we suggest that in attempts to identify methylation loci linking separate MetS components, cg19693031 appears to represent a strong candidate.
  • Kibble, Milla; Khan, Suleiman A.; Ammad-ud-din, Muhammad; Bollepalli, Sailalitha; Palviainen, Teemu; Kaprio, Jaakko; Pietiläinen, Kirsi H.; Ollikainen, Miina (2020)
    We combined clinical, cytokine, genomic, methylation and dietary data from 43 young adult monozygotic twin pairs (aged 22-36 years, 53% female), where 25 of the twin pairs were substantially weight discordant (delta body mass index > 3 kg m(-2)). These measurements were originally taken as part of the TwinFat study, a substudy of The Finnish Twin Cohort study. These five large multivariate datasets (comprising 42, 71, 1587, 1605 and 63 variables, respectively) were jointly analysed using an integrative machine learning method called group factor analysis (GFA) to offer new hypotheses into the multi-molecular-level interactions associated with the development of obesity. New potential links between cytokines and weight gain are identified, as well as associations between dietary, inflammatory and epigenetic factors. This encouraging case study aims to enthuse the research community to boldly attempt new machine learning approaches which have the potential to yield novel and unintuitive hypotheses. The source code of the GFA method is publically available as the R package GFA.
  • Haliloglu, Kamil; Hosseinpour, Arash; Cinisli, Kağan Tolga; Ozturk, Halil Ibrahim; Ozkan, Guller; Pour-Aboughadareh, Alireza; Poczai, Péter (2020)
    Salinity is an edaphic stress that dramatically restricts worldwide crop production. Nanomaterials and plant growth-promoting bacteria (PGPB) are currently used to alleviate the negative effects of various stresses on plant growth and development. This study investigates the protective effects of different levels of zinc oxide nanoparticles (ZnO-NPs) (0, 20, and 40 mg L-1) and PGPBs (no bacteria, Bacillus subtilis, Lactobacillus casei, Bacillus pumilus) on DNA damage and cytosine methylation changes in the tomato (Solanum lycopersicum L. 'Linda') seedlings under salinity stress (250 mM NaCl). Coupled Restriction Enzyme Digestion-Random Amplification (CRED-RA) and Randomly Amplified Polymorphic DNA (RAPD) approaches were used to analyze changes in cytosine methylation and to determine how genotoxic effects influence genomic stability. Salinity stress increased the polymorphism rate assessed by RAPD, while PGPB and ZnO-NPs reduced the adverse effects of salinity stress. Genomic template stability was increased by the PGPBs and ZnO-NPs application; this increase was significant when Lactobacillus casei and 40 mg L-1 of ZnO-NPs were used.A decreased level of DNA methylation was observed in all treatments. Taken together, the use of PGPB and ZnO-NPs had a general positive effect under salinity stress reducing genetic impairment in tomato seedlings.
  • Girchenko, Polina; Lahti, Jari; Czamara, Darina; Knight, Anna K.; Jones, Meaghan J.; Suarez Figueiredo, Anna; Hämäläinen, Esa; Kajantie, Eero; Laivuori, Hannele; Villa, Pia M.; Reynolds, Rebecca M.; Kobor, Michael S.; Smith, Alicia K.; Binder, Elisabeth B.; Räikkönen, Katri (2017)
    Background: A recent study has shown that it is possible to accurately estimate gestational age (GA) at birth from the DNA methylation (DNAm) of fetal umbilical cord blood/newborn blood spots. This DNAm GA predictor may provide additional information relevant to developmental stage. In 814 mother-neonate pairs, we evaluated the associations between DNAm GA and a number of maternal and offspring characteristics. These characteristics reflect prenatal environmental adversity and are expected to influence newborn developmental stage. Results: DNAm GA acceleration (GAA; i.e., older DNAm GA than chronological GA) of the offspring at birth was associated with maternal age of over 40 years at delivery, pre-eclampsia and fetal demise in a previous pregnancy, maternal pre-eclampsia and treatment with antenatal betamethasone in the index pregnancy, lower neonatal birth size, lower 1-min Apgar score, and female sex. DNAm GA deceleration (GAD; i.e., younger DNAm GA than chronological GA) of the offspring at birth was associated with insulin-treated gestational diabetes mellitus (GDM) in a previous pregnancy and Sjogren's syndrome. These findings were more accentuated when the DNAm GA calculation was based on the raw difference between DNAm GA and GA than on the residual from the linear regression of DNAm GA on GA. Conclusions: Our findings show that variations in the DNAm GA of the offspring at birth are associated with a number of maternal and offspring characteristics known to reflect exposure to prenatal environmental adversity. Future studies should be aimed at determining if this biological variation is predictive of developmental adversity.
  • Pussila, Marjaana; Sarantaus, Laura; Dermadi Bebek, Denis; Valo, Satu; Reyhani, Nima; Ollila, Saara; Päivärinta, Essi Mari-Anna; Peltomäki, Päivi T; Mutanen, Marja; Nyström, Minna (2013)
  • Westra, Harm-Jan; Arends, Danny; Esko, Tonu; Peters, Marjolein J.; Schurmann, Claudia; Schramm, Katharina; Kettunen, Johannes; Yaghootkar, Hanieh; Fairfax, Benjamin P.; Andiappan, Anand Kumar; Li, Yang; Fu, Jingyuan; Karjalainen, Juha; Platteel, Mathieu; Visschedijk, Marijn; Weersma, Rinse K.; Kasela, Silva; Milani, Lili; Tserel, Liina; Peterson, Part; Reinmaa, Eva; Hofman, Albert; Uitterlinden, Andre G.; Rivadeneira, Fernando; Homuth, Georg; Petersmann, Astrid; Lorbeer, Roberto; Prokisch, Holger; Meitinger, Thomas; Herder, Christian; Roden, Michael; Grallert, Harald; Ripatti, Samuli; Perola, Markus; Wood, Andrew R.; Melzer, David; Ferrucci, Luigi; Singleton, Andrew B.; Hernandez, Dena G.; Knight, Julian C.; Melchiotti, Rossella; Lee, Bernett; Poidinger, Michael; Zolezzi, Francesca; Larbi, Anis; Wang, De Yun; van den Berg, Leonard H.; Veldink, Jan H.; Rotzschke, Olaf; Makino, Seiko; Salomaa, Veikko; Strauch, Konstantin; Voelker, Uwe; van Meurs, Joyce B. J.; Metspalu, Andres; Wijmenga, Cisca; Jansen, Ritsert C.; Franke, Lude (2015)
    The functional consequences of trait associated SNPs are often investigated using expression quantitative trait locus (eQTL) mapping. While trait-associated variants may operate in a cell-type specific manner, eQTL datasets for such cell-types may not always be available. We performed a genome-environment interaction (GxE) meta-analysis on data from 5,683 samples to infer the cell type specificity of whole blood cis-eQTLs. We demonstrate that this method is able to predict neutrophil and lymphocyte specific cis-eQTLs and replicate these predictions in independent cell-type specific datasets. Finally, we show that SNPs associated with Crohn's disease preferentially affect gene expression within neutrophils, including the archetypal NOD2 locus.
  • Philips, Elise M.; Santos, Susana; Trasande, Leonardo; Aurrekoetxea, Juan J.; Barros, Henrique; von Berg, Andrea; Bergstroem, Anna; Bird, Philippa K.; Brescianini, Sonia; Chaoimh, Carol Ni; Charles, Marie-Aline; Chatzi, Leda; Chevrier, Cecile; Chrousos, George P.; Costet, Nathalie; Criswell, Rachel; Crozier, Sarah; Eggesbo, Merete; Fantini, Maria Pia; Farchi, Sara; Forastiere, Francesco; van Gelder, Marleen M. H. J.; Georgiu, Vagelis; Godfrey, Keith M.; Gori, Davide; Hanke, Wojciech; Heude, Barbara; Hryhorczuk, Daniel; Iniguez, Carmen; Inskip, Hazel; Karvonen, Anne M.; Kenny, Louise C.; Kull, Inger; Lawlor, Debbie A.; Lehmann, Irina; Magnus, Per; Manios, Yannis; Melen, Erik; Mommers, Monique; Morgen, Camilla S.; Moschonis, George; Murray, Deirdre; Nohr, Ellen A.; Andersen, Anne-Marie Nybo; Oken, Emily; Oostvogels, Adriette J. J. M.; Papadopoulou, Eleni; Pekkanen, Juha; Pizzi, Costanza; Polanska, Kinga; Porta, Daniela; Richiardi, Lorenzo; Rifas-Shiman, Sheryl L.; Roeleveld, Nel; Rusconi, Franca; Santos, Ana C.; Sorensen, Thorkild I. A.; Standl, Marie; Stoltenberg, Camilla; Sunyer, Jordi; Thiering, Elisabeth; Thijs, Carel; Torrent, Maties; Vrijkotte, Tanja G. M.; Wright, John; Zvinchuk, Oleksandr; Gaillard, Romy; Jaddoe, Vincent W. V. (2020)
    Author summaryWhy was this study done? Maternal smoking during pregnancy is an important risk factor for various birth complications and childhood overweight. It is not clear whether this increased risk is also present if mothers smoke during the first trimester only or reduce the number of cigarettes during pregnancy. The associations of paternal smoking with birth and childhood outcomes also remain unknown. What did the researchers do and find? We conducted an individual participant data meta-analysis using data from 229,158 families from 28 pregnancy and birth cohorts from Europe and North America to assess the associations of parental smoking during pregnancy, specifically of quitting or reducing smoking and maternal and paternal smoking combined, with preterm birth, small size for gestational age, and childhood overweight. We observed that smoking in the first trimester only did not increase the risk of preterm birth and small size for gestational age but was associated with a higher risk of childhood overweight, as compared to nonsmoking. Reducing the number of cigarettes during pregnancy, without quitting, was still associated with higher risks of these adverse outcomes. Paternal smoking seems to be associated, independently of maternal smoking, with the risks of childhood overweight. What do these findings mean? Population strategies should focus on parental smoking prevention before or at the start of, rather than during, pregnancy. Future studies are needed to assess the specific associations of smoking in the preconception and childhood periods with offspring outcomes. Background Fetal smoke exposure is a common and key avoidable risk factor for birth complications and seems to influence later risk of overweight. It is unclear whether this increased risk is also present if mothers smoke during the first trimester only or reduce the number of cigarettes during pregnancy, or when only fathers smoke. We aimed to assess the associations of parental smoking during pregnancy, specifically of quitting or reducing smoking and maternal and paternal smoking combined, with preterm birth, small size for gestational age, and childhood overweight. Methods and findings We performed an individual participant data meta-analysis among 229,158 families from 28 pregnancy/birth cohorts from Europe and North America. All 28 cohorts had information on maternal smoking, and 16 also had information on paternal smoking. In total, 22 cohorts were population-based, with birth years ranging from 1991 to 2015. The mothers' median age was 30.0 years, and most mothers were medium or highly educated. We used multilevel binary logistic regression models adjusted for maternal and paternal sociodemographic and lifestyle-related characteristics. Compared with nonsmoking mothers, maternal first trimester smoking only was not associated with adverse birth outcomes but was associated with a higher risk of childhood overweight (odds ratio [OR] 1.17 [95% CI 1.02-1.35],Pvalue = 0.030). Children from mothers who continued smoking during pregnancy had higher risks of preterm birth (OR 1.08 [95% CI 1.02-1.15],Pvalue = 0.012), small size for gestational age (OR 2.15 [95% CI 2.07-2.23],Pvalue <0.001), and childhood overweight (OR 1.42 [95% CI 1.35-1.48],Pvalue <0.001). Mothers who reduced the number of cigarettes between the first and third trimester, without quitting, still had a higher risk of small size for gestational age. However, the corresponding risk estimates were smaller than for women who continued the same amount of cigarettes throughout pregnancy (OR 1.89 [95% CI 1.52-2.34] instead of OR 2.20 [95% CI 2.02-2.42] when reducing from 5-9 to = 10 to 5-9 and
  • Voronova, Angelika; Rendón-Anaya, Martha; Ingvarsson, Pär; Kalendar, Ruslan; Ruņģis, Dainis (2020)
    Sequencing the giga-genomes of several pine species has enabled comparative genomic analyses of these outcrossing tree species. Previous studies have revealed the wide distribution and extraordinary diversity of transposable elements (TEs) that occupy the large intergenic spaces in conifer genomes. In this study, we analyzed the distribution of TEs in gene regions of the assembled genomes of Pinus taeda and Pinus lambertiana using high-performance computing resources. The quality of draft genomes and the genome annotation have significant consequences for the investigation of TEs and these aspects are discussed. Several TE families frequently inserted into genes or their flanks were identified in both species' genomes. Potentially important sequence motifs were identified in TEs that could bind additional regulatory factors, promoting gene network formation with faster or enhanced transcription initiation. Node genes that contain many TEs were observed in multiple potential transposable element-associated networks. This study demonstrated the increased accumulation of TEs in the introns of stress-responsive genes of pines and suggests the possibility of rewiring them into responsive networks and sub-networks interconnected with node genes containing multiple TEs. Many such regulatory influences could lead to the adaptive environmental response clines that are characteristic of naturally spread pine populations.
  • Giri, Anil K.; Aittokallio, Tero (2019)
    DNA methyltransferase inhibitors (DNMTi) decitabine and azacytidine are approved therapies for myelodysplastic syndrome and acute myeloid leukemia, and their combinations with other anticancer agents are being tested as therapeutic options for multiple solid cancers such as colon, ovarian, and lung cancer. However, the current therapeutic challenges of DNMTis include development of resistance, severe side effects and no or partial treatment responses, as observed in more than half of the patients. Therefore, there is a critical need to better understand the mechanisms of action of these drugs. In order to discover molecular targets of DNMTi therapy, we identified 638 novel CpGs with an increased methylation in response to decitabine treatment in HCT116 cell lines and validated the findings in multiple cancer types (e.g., bladder, ovarian, breast, and lymphoma) cell lines, bone marrow mononuclear cells from primary leukemia patients, as well as peripheral blood mononuclear cells and ascites from platinum resistance epithelial ovarian cancer patients. Azacytidine treatment also increased methylation of these CpGs in colon, ovarian, breast, and lymphoma cancer cell lines. Methylation at 166 identified CpGs strongly correlated (vertical bar r vertical bar >= 0.80) with corresponding gene expression in HCT116 cell line. Differences in methylation at some of the identified CpGs and expression changes of the corresponding genes was observed in TCGA colon cancer tissue as compared to adjacent healthy tissue. Our analysis revealed that hypermethylated CpGs are involved in cancer cell proliferation and apoptosis by P53 and olfactory receptor pathways, hence influencing DNMTi responses. In conclusion, we showed hypermethylation of CpGs as a novel mechanism of action for DNMTi agents and identified 638 hypermethylated molecular targets (CpGs) common to decitabine and azacytidine therapy. These novel results suggest that hypermethylation of CpGs should be considered when predicting the DNMTi responses and side effects in cancer patients.
  • Dietrich, Sascha; Oles, Malgorzata; Lu, Junyan; Sellner, Leopold; Anders, Simon; Velten, Britta; Wu, Bian; Huellein, Jennifer; Liberio, Michelle da Silva; Walther, Tatjana; Wagner, Lena; Rabe, Sophie; Ghidelli-Disse, Sonja; Bantscheff, Marcus; Oles, Andrzej K.; Slabicki, Mikolaj; Mock, Andreas; Oakes, Christopher C.; Wang, Shihui; Oppermann, Sina; Lukas, Marina; Kim, Vladislav; Sill, Martin; Benner, Axel; Jauch, Anna; Sutton, Lesley Ann; Young, Emma; Rosenquist, Richard; Liu, Xiyang; Jethwa, Alexander; Lee, Kwang Seok; Lewis, Joe; Putzker, Kerstin; Lutz, Christoph; Rossi, Davide; Mokhir, Andriy; Oellerich, Thomas; Zirlik, Katja; Herling, Marco; Nguyen-Khac, Florence; Plass, Christoph; Andersson, Emma; Mustjoki, Satu; von Kalle, Christof; Ho, Anthony D.; Hensel, Manfred; Duerig, Jan; Ringshausen, Ingo; Zapatka, Marc; Huber, Wolfgang; Zenz, Thorsten (2018)
    As new generations of targeted therapies emerge and tumor genome sequencing discovers increasingly comprehensive mutation repertoires, the functional relationships of mutations to tumor phenotypes remain largely unknown. Here, we measured ex vivo sensitivity of 246 blood cancers to 63 drugs alongside genome, transcriptome, and DNA methylome analysis to understand determinants of drug response. We assembled a primary blood cancer cell encyclopedia data set that revealed disease-specific sensitivities for each cancer. Within chronic lymphocytic leukemia (CLL), responses to 62% of drugs were associated with 2 or more mutations, and linked the B cell receptor (BCR) pathway to trisomy 12, an important driver of CLL. Based on drug responses, the disease could be organized into phenotypic subgroups characterized by exploitable dependencies on BCR, mTOR, or MEK signaling and associated with mutations, gene expression, and DNA methylation. Fourteen percent of CLLs were driven by mTOR signaling in a non-BCR-dependent manner. Multivariate modeling revealed immunoglobulin heavy chain variable gene (IGHV) mutation status and trisomy 12 as the most important modulators of response to kinase inhibitors in CLL. Ex vivo drug responses were associated with outcome. This study overcomes the perception that most mutations do not influence drug response of cancer, and points to an updated approach to understanding tumor biology, with implications for biomarker discovery and cancer care.
  • McCrory, Cathal; Fiorito, Giovanni; McLoughlin, Sinead; Polidoro, Silvia; Cheallaigh, Cliona Ni; Bourke, Nollaig; Karisola, Piia; Alenius, Harri; Vineis, Paolo; Layte, Richard; Kenny, Rose Anne (2020)
    Allostatic load (AL) and epigenetic clocks both attempt to characterize the accelerated aging of biological systems, but at present it is unclear whether these measures are complementary or distinct. This study examines the cross-sectional association of AL with epigenetic age acceleration (EAA) in a subsample of 490 community-dwelling older adults participating in The Irish Longitudinal study on Aging (TILDA). A battery of 14 biomarkers representing the activity of four different physiological systems: immunological, cardiovascular, metabolic, renal, was used to construct the AL score. DNA methylation age was computed according to the algorithms described by Horvath, Hannum, and Levine allowing for estimation of whether an individual is experiencing accelerated or decelerated aging. Horvath, Hannum, and Levine EAA correlated 0.05, 0.03, and 0.21 with AL, respectively. Disaggregation by sex revealed that AL was more strongly associated with EAA in men compared with women as assessed using Horvath's clock. Metabolic dysregulation was a strong driver of EAA in men as assessed using Horvath and Levine's clock, while metabolic and cardiovascular dysregulation were associated with EAA in women using Levine's clock. Results indicate that AL and the epigenetic clocks are measuring different age-related variance and implicate sex-specific drivers of biological aging.
  • Zannas, Anthony S.; Jia, Meiwen; Hafner, Kathrin; Baumert, Jens; Wiechmann, Tobias; Pape, Julius C.; Arloth, Janine; Ködel, Maik; Martinelli, Silvia; Roitman, Maria; Roeh, Simone; Haehle, Andreas; Emeny, Rebecca T.; Iurato, Stella; Carrillo-Roa, Tania; Lahti, Jari; Räikkönen, Katri; Eriksson, Johan G.; Drake, Amanda J.; Waldenberger, Melanie; Wahl, Simone; Kunze, Sonja; Lucae, Susanne; Bradley, Bekh; Gieger, Christian; Hausch, Felix; Smith, Alicia K.; Ressler, Kerry J.; Mueller-Myhsok, Bertram; Ladwig, Karl-Heinz; Rein, Theo; Gassen, Nils C.; Binder, Elisabeth B. (2019)
    Aging and psychosocial stress are associated with increased inflammation and disease risk, but the underlying molecular mechanisms are unclear. Because both aging and stress are also associated with lasting epigenetic changes, a plausible hypothesis is that stress along the lifespan could confer disease risk through epigenetic effects on molecules involved in inflammatory processes. Here, by combining large-scale analyses in human cohorts with experiments in cells, we report that FKBP5, a protein implicated in stress physiology, contributes to these relations. Across independent human cohorts (total n > 3,000), aging synergized with stress-related phenotypes, measured with childhood trauma and major depression questionnaires, to epigenetically up-regulate FKBP5 expression. These age/stress-related epigenetic effects were recapitulated in a cellular model of replicative senescence, whereby we exposed replicating human fibroblasts to stress (glucocorticoid) hormones. Unbiased genome-wide analyses in human blood linked higher FKBP5 mRNA with a proinflammatory profile and altered NF-kappa B-related gene networks. Accordingly, experiments in immune cells showed that higher FKBP5 promotes inflammation by strengthening the interactions of NF-kappa B regulatory kinases, whereas opposing FKBP5 either by genetic deletion (CRISPR/Cas9-mediated) or selective pharmacological inhibition prevented the effects on NF-kappa B. Further, the age/stress-related epigenetic signature enhanced FKBP5 response to NF-kappa B through a positive feedback loop and was present in individuals with a history of acute myocardial infarction, a disease state linked to peripheral inflammation. These findings suggest that aging/stress-driven FKBP5-NF-kappa B signaling mediates inflammation, potentially contributing to cardiovascular risk, and may thus point to novel biomarker and treatment possibilities.
  • Mishra, Pashupati P.; Hänninen, Ismo; Raitoharju, Emma; Marttila, Saara; Mishra, Binisha H.; Mononen, Nina; Kähönen, Mika; Hurme, Mikko; Raitakari, Olli; Törönen, Petri; Holm, Liisa; Lehtimaki, Terho (2020)
    Smoking as a major risk factor for morbidity affects numerous regulatory systems of the human body including DNA methylation. Most of the previous studies with genome-wide methylation data are based on conventional association analysis and earliest threshold-based gene set analysis that lacks sensitivity to be able to reveal all the relevant effects of smoking. The aim of the present study was to investigate the impact of active smoking on DNA methylation at three biological levels: 5'-C-phosphate-G-3' (CpG) sites, genes and functionally related genes (gene sets). Gene set analysis was done with mGSZ, a modern threshold-free method previously developed by us that utilizes all the genes in the experiment and their differential methylation scores. Application of such method in DNA methylation study is novel. Epigenome-wide methylation levels were profiled from Young Finns Study (YFS) participants' whole blood from 2011 follow-up using Illumina Infinium Hu-manMethylation450 BeadChips. We identified three novel smoking related CpG sites and replicated 57 of the previously identified ones. We found that smoking is associated with hypomethylation in shore (genomic regions 0-2 kilobases from CpG island). We identified smoking related methylation changes in 13 gene sets with false discovery rate (FDR)
  • Imboden, Medea; Wielscher, Matthias; Rezwan, Faisal I.; Amaral, Andre F. S.; Schaffner, Emmanuel; Jeong, Ayoung; Beckmeyer-Borowko, Anna; Harris, Sarah E.; Starr, John M.; Deary, Ian J.; Flexeder, Claudia; Waldenberger, Melanie; Peters, Annette; Schulz, Holger; Chen, Su; Sunny, Shadia Khan; Karmaus, Wilfried J. J.; Jiang, Yu; Erhart, Gertraud; Kronenberg, Florian; Arathimos, Ryan; Sharp, Gemma C.; Henderson, Alexander John; Fu, Yu; Piirilä, Päivi; Pietiläinen, Kirsi H.; Ollikainen, Miina; Johansson, Asa; Gyllensten, Ulf; de Vries, Maaike; van der Plaat, Diana A.; de Jong, Kim; Boezen, H. Marike; Hall, Ian P.; Tobin, Martin D.; Jarvelin, Marjo-Riitta; Holloway, John W.; Jarvis, Deborah; Probst-Hensch, Nicole M. (2019)
    Previous reports link differential DNA methylation (DNAme) to environmental exposures that are associated with lung function. Direct evidence on lung function DNAme is, however, limited. We undertook an agnostic epigenome-wide association study (EWAS) on pre-bronchodilation lung function and its change in adults. In a discovery-replication EWAS design, DNAme in blood and spirometry were measured twice, 6-15 years apart, in the same participants of three adult population-based discovery cohorts (n=2043). Associated DNAme markers (p EWAS signals were enriched for smoking-related DNAme. We replicated 57 lung function DNAme markers in adult, but not childhood samples, all previously associated with smoking. Markers not previously associated with smoking failed replication. cg05575921 (AHRR (aryl hydrocarbon receptor repressor)) showed the statistically most significant association with cross-sectional lung function (FEV1/FVC: pdiscovery=3.96x10(-21) and pcombined=7.22x10(-50)). A score combining 10 DNAme markers previously reported to mediate the effect of smoking on lung function was associated with lung function (FEV1/FVC: p=2.65x10(-20)). Our results reveal that lung function-associated methylation signals in adults are predominantly smoking related, and possibly of clinical utility in identifying poor lung function and accelerated decline. Larger studies with more repeat time-points are needed to identify lung function DNAme in never-smokers and in children.
  • Jackson, Matilda R.; Loring, Karagh E.; Homan, Claire C.; Thai, Monica H. N.; Maattanen, Laura; Arvio, Maria; Järvelä, Irma; Shaw, Marie; Gardner, Alison; Gecz, Jozef; Shoubridge, Cheryl (2019)
    Clinical presentations of mutations in the IQSEC2 gene on the X-chromosome initially implicated to cause non-syndromic intellectual disability (ID) in males have expanded to include early onset seizures in males as well as in females. The molecular pathogenesis is not well understood, nor the mechanisms driving disease expression in heterozygous females. Using a CRISPR/Cas9-edited Iqsec2 KO mouse model, we confirm the loss of Iqsec2 mRNA expression and lack of Iqsec2 protein within the brain of both founder and progeny mice. Both male (52%) and female (46%) Iqsec2 KO mice present with frequent and recurrent seizures. Focusing on Iqsec2 KO heterozygous female mice, we demonstrate increased hyperactivity, altered anxiety and fear responses, decreased social interactions, delayed learning capacity and decreased memory retention/novel recognition, recapitulating psychiatric issues, autistic-like features, and cognitive deficits present in female patients with loss-of-function IQSEC2 variants. Despite Iqsec2 normally acting to activate Arf6 substrate, we demonstrate that mice modelling the loss of Iqsec2 function present with increased levels of activated Arf6. We contend that loss of Iqsec2 function leads to altered regulation of activated Arf6-mediated responses to synaptic signalling and immature synaptic networks. We highlight the importance of IQSEC2 function for females by reporting a novel nonsense variant c.566C > A, p.(S189*) in an elderly female patient with profound intellectual disability, generalised seizures, and behavioural disturbances. Our human and mouse data reaffirm IQSEC2 as another disease gene with an unexpected X-chromosome heterozygous female phenotype. Our Iqsec2 mouse model recapitulates the phenotypes observed in human patients despite the differences in the IQSEC2/Iqsec2 gene X-chromosome inactivation between the species.