@misc{PonceSchererBoekstegersetal.2019, author = {Ponce, Carol Barahona and Scherer, Dominique and Boekstegers, Felix and Garate-Calderon, Valentina and Jenab, Mazda and Aleksandrova, Krasimira and Katzke, Verena and Weiderpass, Elisabete and Bonet, Catalina and Moradi, Tahereh and Fischer, Krista and Bossers, Willem and Brenner, Hermann and Sch{\"o}ttker, Ben and Holleczek, Bernd and Hveem, Kristian and Eklund, Niina and Voelker, Uwe and Waldenberger, Melanie and Bermejo, Justo Lorenzo}, title = {Arsenic and gallbladder cancer risk}, series = {International journal of cancer}, volume = {146}, journal = {International journal of cancer}, number = {9}, publisher = {Wiley}, address = {Hoboken}, issn = {0020-7136}, doi = {10.1002/ijc.32837}, pages = {2648 -- 2650}, year = {2019}, language = {en} } @article{WirschingGrassmannEichelmannetal.2018, author = {Wirsching, Jan and Grassmann, Sophie and Eichelmann, Fabian and Harms, Laura Malin and Schenk, Matthew and Barth, Eva and Berndzen, Alide and Olalekan, Moses and Sarmini, Leen and Zuberer, Hedwig and Aleksandrova, Krasimira}, title = {Development and reliability assessment of a new quality appraisal tool for cross-sectional studies using biomarker data (BIOCROSS)}, series = {BMC Medical Research Methodology}, volume = {18}, journal = {BMC Medical Research Methodology}, publisher = {BMC}, address = {London}, issn = {1471-2288}, doi = {10.1186/s12874-018-0583-x}, pages = {8}, year = {2018}, abstract = {Background Biomarker-based analyses are commonly reported in observational epidemiological studies; however currently there are no specific study quality assessment tools to assist evaluation of conducted research. Accounting for study design and biomarker measurement would be important for deriving valid conclusions when conducting systematic data evaluation. Methods We developed a study quality assessment tool designed specifically to assess biomarker-based cross-sectional studies (BIOCROSS) and evaluated its inter-rater reliability. The tool includes 10-items covering 5 domains: 'Study rational', 'Design/Methods', 'Data analysis', 'Data interpretation' and 'Biomarker measurement', aiming to assess different quality features of biomarker cross-sectional studies. To evaluate the inter-rater reliability, 30 studies were distributed among 5 raters and intraclass correlation coefficients (ICC-s) were derived from respective ratings. Results The estimated overall ICC between the 5 raters was 0.57 (95\% Confidence Interval (CI): 0.38-0.74) indicating a good inter-rater reliability. The ICC-s ranged from 0.11 (95\% CI: 0.01-0.27) for the domain 'Study rational' to 0.56 (95\% CI: 0.40-0.72) for the domain 'Data interpretation'. Conclusion BIOCROSS is a new study quality assessment tool suitable for evaluation of reporting quality from cross-sectional epidemiological studies employing biomarker data. The tool proved to be reliable for use by biomedical scientists with diverse backgrounds and could facilitate comprehensive review of biomarker studies in human research.}, language = {en} } @article{GrajaGarciaCarrizoJanketal.2018, author = {Graja, Antonia and Garcia-Carrizo, Francisco and Jank, Anne-Marie and Gohlke, Sabrina and Ambrosi, Thomas H. and Jonas, Wenke and Ussar, Siegfried and Kern, Matthias and Sch{\"u}rmann, Annette and Aleksandrova, Krasimira and Bluher, Matthias and Schulz, Tim Julius}, title = {Loss of periostin occurs in aging adipose tissue of mice and its genetic ablation impairs adipose tissue lipid metabolism}, series = {Aging Cell}, volume = {17}, journal = {Aging Cell}, number = {5}, publisher = {Wiley}, address = {Hoboken}, issn = {1474-9718}, doi = {10.1111/acel.12810}, pages = {13}, year = {2018}, abstract = {Remodeling of the extracellular matrix is a key component of the metabolic adaptations of adipose tissue in response to dietary and physiological challenges. Disruption of its integrity is a well-known aspect of adipose tissue dysfunction, for instance, during aging and obesity. Adipocyte regeneration from a tissue-resident pool of mesenchymal stem cells is part of normal tissue homeostasis. Among the pathophysiological consequences of adipogenic stem cell aging, characteristic changes in the secretory phenotype, which includes matrix-modifying proteins, have been described. Here, we show that the expression of the matricellular protein periostin, a component of the extracellular matrix produced and secreted by adipose tissue-resident interstitial cells, is markedly decreased in aged brown and white adipose tissue depots. Using a mouse model, we demonstrate that the adaptation of adipose tissue to adrenergic stimulation and high-fat diet feeding is impaired in animals with systemic ablation of the gene encoding for periostin. Our data suggest that loss of periostin attenuates lipid metabolism in adipose tissue, thus recapitulating one aspect of age-related metabolic dysfunction. In human white adipose tissue, periostin expression showed an unexpected positive correlation with age of study participants. This correlation, however, was no longer evident after adjusting for BMI or plasma lipid and liver function biomarkers. These findings taken together suggest that age-related alterations of the adipose tissue extracellular matrix may contribute to the development of metabolic disease by negatively affecting nutrient homeostasis.}, language = {en} } @article{BoekstegersMarcelainBarahonaPonceetal.2020, author = {Boekstegers, Felix and Marcelain, Katherine and Barahona Ponce, Carol and Baez Benavides, Pablo F. and M{\"u}ller, Bettina and de Toro, Gonzalo and Retamales, Javier and Barajas, Olga and Ahumada, Monica and Aleksandrova, Krasimira and Bermejo, Justo Lorenzo}, title = {ABCB1/4 gallbladder cancer risk variants identified in India also show strong effects in Chileans}, series = {Cancer Epidemiology}, volume = {65}, journal = {Cancer Epidemiology}, publisher = {Elsevier}, address = {Amsterdam}, pages = {5}, year = {2020}, abstract = {Background: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence. Methods: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication. Results: Our results confirmed the reported associations for Chileans with similar risk effects. Particularly strong associations (per-allele odds ratios close to 2) were observed for Chileans with high Native American (=Mapuche) ancestry. No associations were noticed for Europeans, but the statistical power was low. Conclusion: Taking full advantage of genetic and ethnic differences in GBC risk may improve the efficiency of current prevention programs.}, language = {en} } @misc{BoekstegersMarcelainBarahonaPonceetal.2020, author = {Boekstegers, Felix and Marcelain, Katherine and Barahona Ponce, Carol and Baez Benavides, Pablo F. and M{\"u}ller, Bettina and de Toro, Gonzalo and Retamales, Javier and Barajas, Olga and Ahumada, Monica and Aleksandrova, Krasimira and Bermejo, Justo Lorenzo}, title = {ABCB1/4 gallbladder cancer risk variants identified in India also show strong effects in Chileans}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, issn = {1866-8372}, doi = {10.25932/publishup-52683}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-526833}, pages = {7}, year = {2020}, abstract = {Background: The first large-scale genome-wide association study of gallbladder cancer (GBC) recently identified and validated three susceptibility variants in the ABCB1 and ABCB4 genes for individuals of Indian descent. We investigated whether these variants were also associated with GBC risk in Chileans, who show the highest incidence of GBC worldwide, and in Europeans with a low GBC incidence. Methods: This population-based study analysed genotype data from retrospective Chilean case-control (255 cases, 2042 controls) and prospective European cohort (108 cases, 181 controls) samples consistently with the original publication. Results: Our results confirmed the reported associations for Chileans with similar risk effects. Particularly strong associations (per-allele odds ratios close to 2) were observed for Chileans with high Native American (=Mapuche) ancestry. No associations were noticed for Europeans, but the statistical power was low. Conclusion: Taking full advantage of genetic and ethnic differences in GBC risk may improve the efficiency of current prevention programs.}, language = {en} } @misc{HarmsScalbertZamoraRosetal.2020, author = {Harms, Laura M. and Scalbert, Augustin and Zamora-Ros, Raul and Rinaldi, Sabina and Jenab, Mazda and Murphy, Neil and Achaintre, David and Tj{\o}nneland, Anne and Olsen, Anja and Overvad, Kim and Aleksandrova, Krasimira}, title = {Plasma polyphenols associated with lower high-sensitivity C-reactive protein concentrations}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {2}, issn = {1866-8372}, doi = {10.25932/publishup-51577}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-515774}, pages = {13}, year = {2020}, abstract = {Experimental studies have reported on the anti-inflammatory properties of polyphenols. However, results from epidemiological investigations have been inconsistent and especially studies using biomarkers for assessment of polyphenol intake have been scant. We aimed to characterise the association between plasma concentrations of thirty-five polyphenol compounds and low-grade systemic inflammation state as measured by high-sensitivity C-reactive protein (hsCRP). A cross-sectional data analysis was performed based on 315 participants in the European Prospective Investigation into Cancer and Nutrition cohort with available measurements of plasma polyphenols and hsCRP. In logistic regression analysis, the OR and 95 \% CI of elevated serum hsCRP (>3 mg/l) were calculated within quartiles and per standard deviation higher level of plasma polyphenol concentrations. In a multivariable-adjusted model, the sum of plasma concentrations of all polyphenols measured (per standard deviation) was associated with 29 (95 \% CI 50, 1) \% lower odds of elevated hsCRP. In the class of flavonoids, daidzein was inversely associated with elevated hsCRP (OR 0 center dot 66, 95 \% CI 0 center dot 46, 0 center dot 96). Among phenolic acids, statistically significant associations were observed for 3,5-dihydroxyphenylpropionic acid (OR 0 center dot 58, 95 \% CI 0 center dot 39, 0 center dot 86), 3,4-dihydroxyphenylpropionic acid (OR 0 center dot 63, 95 \% CI 0 center dot 46, 0 center dot 87), ferulic acid (OR 0 center dot 65, 95 \% CI 0 center dot 44, 0 center dot 96) and caffeic acid (OR 0 center dot 69, 95 \% CI 0 center dot 51, 0 center dot 93). The odds of elevated hsCRP were significantly reduced for hydroxytyrosol (OR 0 center dot 67, 95 \% CI 0 center dot 48, 0 center dot 93). The present study showed that polyphenol biomarkers are associated with lower odds of elevated hsCRP. Whether diet rich in bioactive polyphenol compounds could be an effective strategy to prevent or modulate deleterious health effects of inflammation should be addressed by further well-powered longitudinal studies.}, language = {en} } @article{KoelmanPivovarovaRamichPfeifferetal.2019, author = {Koelman, Liselot A. and Pivovarova-Ramich, Olga and Pfeiffer, Andreas F. H. and Grune, Tilman and Aleksandrova, Krasimira}, title = {Cytokines for evaluation of chronic inflammatory status in ageing research}, series = {Immunity \& Ageing}, volume = {16}, journal = {Immunity \& Ageing}, publisher = {BMC}, address = {London}, issn = {1742-4933}, doi = {10.1186/s12979-019-0151-1}, pages = {12}, year = {2019}, abstract = {Background: There is a growing interest in the role of inflammageing for chronic disease development. Cytokines are potent soluble immune mediators that can be used as target biomarkers of inflammageing; however, their measurement in human samples has been challenging. This study aimed to assess the reliability of a pro- and anti-inflammatory cytokine panel in a sample of healthy people measured with a novel electrochemiluminescent multiplex immunoassay platform (Meso Scale Discovery, MSD), and to characterize their associations with metabolic and inflammatory phenotypes.}, language = {en} } @article{SchenkEichelmannSchulzeetal.2019, author = {Schenk, Matthew and Eichelmann, Fabian and Schulze, Matthias Bernd and Rudovich, Natalia and Pfeiffer, Andreas F. H. and di Giuseppe, Romina and B{\"o}ing, Heiner and Aleksandrova, Krasimira}, title = {Reproducibility of novel immune-inflammatory biomarkers over 4 months}, series = {Biomarkers in medicine}, volume = {13}, journal = {Biomarkers in medicine}, number = {8}, publisher = {Future Medicine}, address = {London}, issn = {1752-0363}, doi = {10.2217/bmm-2018-0351}, pages = {639 -- 648}, year = {2019}, abstract = {Aim: Assessment of the feasibility and reliability of immune-inflammatory biomarker measurements. Methods: The following biomarkers were assessed in 207 predominantly healthy participants at baseline and after 4 months: MMF, TGF-beta, suPAR and clusterin. Results: Intraclass correlation coefficients (95\% CIs) ranged from good for TGF-beta (0.75 [95\% CI: 0.33-0.90]) to excellent for MMF (0.81 [95\% CI: 0.64-0.90]), clusterin (0.83 [95\% CI: 0.78-0.87]) and suPAR (0.91 [95\% CI: 0.88-0.93]). Measurement of TGF-beta was challenged by the large number of values below the detection limit. Conclusion: Single measurements of suPAR, clusterin and MMF could serve as feasible and reliable biomarkers of immune-inflammatory pathways in biomedical research.}, language = {en} } @article{EichelmannSchulzeWittenbecheretal.2019, author = {Eichelmann, Fabian and Schulze, Matthias Bernd and Wittenbecher, Clemens and Menzel, Juliane and Weikert, Cornelia and di Giuseppe, Romina and Biemann, Ronald and Isermann, Berend and Fritsche, Andreas and Boeing, Heiner and Aleksandrova, Krasimira}, title = {Association of Chemerin Plasma Concentration With Risk of Colorectal Cancer}, series = {JAMA network open}, volume = {2}, journal = {JAMA network open}, number = {3}, publisher = {American Veterinary Medical Association}, address = {Chicago}, issn = {2574-3805}, doi = {10.1001/jamanetworkopen.2019.0896}, pages = {14}, year = {2019}, abstract = {IMPORTANCE Inflammatory processes have been suggested to have an important role in colorectal cancer (CRC) etiology. Chemerin is a recently discovered inflammatory biomarker thought to exert chemotactic, adipogenic, and angiogenic functions. However, its potential link with CRC has not been sufficiently explored. OBJECTIVE To evaluate the prospective association of circulating plasma chemerin concentrations with incident CRC. DESIGN, SETTING, AND PARTICIPANTS Prospective case-cohort study based on 27 548 initially healthy participants from the European Prospective Investigation Into Cancer and Nutrition (EPIC)-Potsdam cohort who were followed for up to 16 years. Baseline study information and samples were collected between August 23, 1994, and September 25, 1998. Recruitment was according to random registry sampling from the geographical area of Potsdam, Germany, and surrounding municipalities. The last date of study follow-up was May 10, 2010. Statistical analysis was conducted in 2018. MAIN OUTCOMES AND MEASURES Incident CRC, colon cancer, and rectal cancer. Baseline chemerin plasma concentrations were measured by enzyme-linked immunosorbent assay. CONCLUSIONS AND RELEVANCE This study found that the association between chemerin concentration and the risk of incident CRC was linear and independent of established CRC risk factors. Further studies are warranted to evaluate chemerin as a novel immune-inflammatory agent in colorectal carcinogenesis.}, language = {en} } @phdthesis{Aleksandrova2020, author = {Aleksandrova, Krasimira}, title = {Understanding the link between obesity and colorectal cancer}, school = {Universit{\"a}t Potsdam}, year = {2020}, language = {de} }