1
|
Korhonen T, Hjelmborg J, Harris JR, Clemmensen S, Adami HO, Kaprio J. Cancer in twin pairs discordant for smoking: The Nordic Twin Study of Cancer. Int J Cancer 2022; 151:33-43. [PMID: 35143046 PMCID: PMC9304125 DOI: 10.1002/ijc.33963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 01/17/2022] [Indexed: 11/17/2022]
Abstract
The discordant twin pair study design is powerful to control for familial confounding. We employed this approach to investigate the associations of smoking with several cancers. The NorTwinCan study combines data from the Danish, Finnish, Norwegian and Swedish twin and cancer registries. Follow‐up started when smoking status was determined and ended at cancer diagnosis confirmed by information in the cancer registry, death or end of follow‐up. We classified the participants as never (n = 59 093), former (n = 21 168) or current (n = 47 314) smokers. We pooled data from twin pairs where one co‐twin was diagnosed with any of the following tobacco‐related cancers: esophagus, kidney, larynx, liver, oral cavity, pancreas, pharynx or urinary bladder, while their co‐twin had none of those. Lung cancer was included in further analysis. We used Cox regression allowing for pair‐specific baseline functions to estimate hazard ratios (HRs) with 95% confidence intervals (CIs). For tobacco‐related cancer sites, we recorded 7379 cases during median 27 years of follow‐up. The analyses based on individual twins showed that former (HR 1.31, 95% CI: 1.17‐1.48) and current (HR 2.14 [1.95‐2.34]) smokers are at increased risk to develop one of cancers listed above, compared to never smokers. Among 109 monozygotic twin pairs discordant for cancer and smoking, the HR was 1.85 (95% CI: 1.15‐2.98) among current smokers and 1.69 (1.00‐2.87) among former smokers when compared to their never smoking co‐twin. Thus, associations of smoking with several cancers were replicated for discordant identical twin pairs. Analyses based on genetically informative data provide evidence consistent with smoking causing multiple cancers.
Collapse
Affiliation(s)
- Tellervo Korhonen
- Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
| | - Jacob Hjelmborg
- Department of Epidemiology, Biostatistics and Biodemography, University of Southern Denmark.,Denmark and the Danish Twin Registry, University of Southern Denmark, Odense, Denmark
| | - Jennifer R Harris
- Center for Fertility and Health, The Norwegian Institute of Public Health, Oslo, Norway
| | - Signe Clemmensen
- Department of Epidemiology, Biostatistics and Biodemography, University of Southern Denmark.,Denmark and the Danish Twin Registry, University of Southern Denmark, Odense, Denmark
| | - Hans-Olov Adami
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden.,Clinical Effectiveness Group, Institute of Health, University of Oslo, Oslo, Norway
| | - Jaakko Kaprio
- Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
| | | |
Collapse
|
2
|
Wang L, Mohammadnejad A, Li W, Lund J, Li S, Clemmensen S, Timofeeva M, Soerensen M, Mengel-From J, Christensen K, Hjelmborg J, Tan Q. Genetic and environmental determinants of O 6-methylguanine DNA-methyltransferase (MGMT) gene methylation: a 10-year longitudinal study of Danish twins. Clin Epigenetics 2021; 13:35. [PMID: 33588926 PMCID: PMC7885436 DOI: 10.1186/s13148-021-01009-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Accepted: 01/07/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Epigenetic inactivation of O6-methylguanine DNA-methyltransferase (MGMT) is associated with increased sensitivity to alkylating chemotherapeutic agents in glioblastoma patients. The genetic background underlying MGMT gene methylation may explain individual differences in treatment response and provide a clue to a personalized treatment strategy. Making use of the longitudinal twin design, we aimed, for the first time, to estimate the genetic contributions to MGMT methylation in a Danish twin cohort. METHODS DNA-methylation from whole blood (18 monozygotic (MZ) and 25 dizygotic (DZ) twin pairs) repeated 10 years apart from the Longitudinal Study of Aging Danish Twins (LSADT) were used to search for genetic and environmental contributions to DNA-methylation at 170 CpG sites of across the MGMT gene. Both univariate and bivariate twin models were applied. The intraclass correlations, performed on cross-sectional data (246 MZ twin pairs) from an independent study population, the Middle-Aged Danish Twins (MADT), were used to assess the genetic influence at each CpG site of MGMT for replication. RESULTS Univariate twin model revealed twelve CpG sites showing significantly high heritability at intake (wave 1, h2 > 0.43), and seven CpG sites with significant heritability estimates at end of follow-up (wave 2, h2 > 0.5). There were six significant CpG sites, located at the gene body region, that overlapped among the two waves (h2 > 0.5), of which five remained significant in the bivariate twin model, which was applied to both waves. Within MZ pair correlation in these six CpGs from MADT demarks top level of genetic influence. There were 11 CpGs constantly have substantial common environmental component over the 10 years. CONCLUSIONS We have identified 6 CpG sites linked to the MGMT gene with strong and persistent genetic control based on their DNA methylation levels. The genetic basis of MGMT gene methylation could help to explain individual differences in glioblastoma treatment response and most importantly, provide references for mapping the methylation Quantitative Trait Loci (meQTL) underlying the genetic regulation.
Collapse
Affiliation(s)
- Lijie Wang
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark.,Department of Epidemiology and Health Statistics, School of Public Health, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Afsaneh Mohammadnejad
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark
| | - Weilong Li
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark.,Population Research Unit, Faculty of Social Sciences, University of Helsinki, Helsinki, Finland
| | - Jesper Lund
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark.,Digital Health and Machine Learning Research Group, Hasso Plattner Institute for Digital Engineering, Potsdam, Germany
| | - Shuxia Li
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark
| | - Signe Clemmensen
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark
| | - Maria Timofeeva
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark
| | - Mette Soerensen
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark
| | - Jonas Mengel-From
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark
| | - Kaare Christensen
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark.,Unit of Human Genetics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Jacob Hjelmborg
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark
| | - Qihua Tan
- Epidemiology, Biostatistics and Biodemography, Department of Public Health, University of Southern Denmark, J.B. Winsløws Vej 9 B., 5000, Odense C, Denmark. .,Unit of Human Genetics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark.
| |
Collapse
|
4
|
Abstract
Combinations of ethanol and urethane were added to the drinking-water of female strain A/Ph mice for 12 wk, at the end of which the animals were killed. Urethane concentrations were 0, 200, 500 and 1000 ppm and ethanol concentrations, 0, 5, 10 and 20% (v/v). All possible combinations of these urethane and ethanol concentrations were tested. Urethane induced primary lung adenomas in all treated mice in a dose-dependent manner. An average of 71 +/- 15 tumours/mouse were found, when the animals were killed, after treatment with 1000 ppm urethane for 12 wk. Ethanol alone did not alter the background incidence of tumours and produced only marginal hepatotoxicity. The tumour yields induced by urethane treatment were greatly reduced by simultaneous treatment with ethanol. The effect of ethanol was independent of urethane dose. When the concentrations of ethanol in the drinking-water were 20 and 10% the incidences of lung adenomas induced by urethane were reduced by about two-thirds and one-half, respectively. The effect of 5% ethanol, if any, was not statistically significant.
Collapse
Affiliation(s)
- E Kristiansen
- Institute of Toxicology, National Food Agency, Søborg, Denmark
| | | | | |
Collapse
|
5
|
Kristiansen E, Clemmensen S, Olsen P. Carcinogenic potential of cooked food mutagens (IQ and MeIQ) in Wistar rats after short-term exposure. Pharmacol Toxicol 1989; 65:332-5. [PMID: 2622864 DOI: 10.1111/j.1600-0773.1989.tb01183.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Two potent cooked food mutagens, 2-amino-3-methylimidazo/4,5-f/quinoline (IQ) and 2-amino-3,4-dimethylimidazo/4,5-f/quinoline (MeIQ), were examined in an initiation-promotion assay in the male wistar rat. Fourteen doses of 10 mg IQ or 10 mg MeIQ/kg b.wt. were given during initiation, followed by promotion with 500 p.p.m. phenobarbital sodium (PB) in the drinking water up to week 58. A small number of tumours of Zymbal's gland were seen in all groups treated with IQ or MeIQ, irrespective of PB-treatment. Though the promotional regimen failed to produce the expected number of liver tumours, it did induce a significant amount of gamma-glutamyltranspeptidase (GGT) activity. These results suggest that even short exposures to low doses of IQ or MeIQ produce persistent procarcinogenic lesions in the rat, and that secondary factors, e.g. promoters or high cell turnover, may over time develop these lesions into cancer.
Collapse
Affiliation(s)
- E Kristiansen
- Institute of Toxicology, National Food Agency, Søoborg, Denmark
| | | | | |
Collapse
|
8
|
Abstract
Amberlite XAD-2 purified urine extracts from rats treated dermally with 1,3-diaminobenzene were fractionated by HPLC and the metabolites were identified by GC-MS. Mutagenic activity in Salmonella typhimurium TA 98 was equally distributed between the two fractions, none of which contained the parent amine. The first fraction, eluted between 2-7 minutes, contained only a very small amount of presently unidentified metabolites, while the second fraction eluted between 14-19 minutes contained N,N'-diacetyl-1,3-diaminobenzene. Both fractions showed minor, but still significant activity even without metabolic activation. A non-mutagenic fraction, eluted between 10-12 minutes contained N-acetyl -acetyl-1,3-diaminobenzene and N,N'-diacetyl-2,4-diaminophenol.
Collapse
|