1
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Liu G. Chromosomal aberration analysis: Novel noninvasive techniques for early-stage cancer screening. Clin Chim Acta 2024; 560:119736. [PMID: 38763468 DOI: 10.1016/j.cca.2024.119736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2024] [Revised: 05/07/2024] [Accepted: 05/14/2024] [Indexed: 05/21/2024]
Abstract
OBJECTIVE Chromosome breakage is a catastrophic event that leads to the progressive development and progression of cancer. In order to analyze the changes of peripheral blood microenvironment of tumor patients, to explore the indicators of non-specific non-invasive tumor early screening. This paper presents a new idea of whether the gene sequence near the DNA damage break point is the gene sequence that controls the unrestricted growth of normal cells. METHODS The chromosomal aberrations of peripheral blood lymphocytes were analysed in 60 healthy adult and 49 cancer patients before radiotherapy. RESULTS The detection rate of chromosomal aberrations was high in tumor patients, and "dicentric + translocations" of chromosomes were detected in 36 patients (73.47 %). The chi-square test showed statistically significant differences (P < 0.01), and chromosome adhesion and dissolution were observed. CONCLUSIONS "Dicentric + Translocation" chromosome can be used as a nonspecific early screening indicator for cancer. This is worthy of further study. This index can be used to determine the genetic basis of various cancers at the gene level to modify the base sequence and prevent the occurrence of cancer. It is worthy of further study, and it can provide a new method for gene therapy of tumors.
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Affiliation(s)
- Gang Liu
- Gansu Provincial Center for Disease Control and Prevention, (Joint Laboratory of Institute of Radiology, Chinese Academy of Medical Sciences), NO.310 Donggang West Road, Lanzhou, Gansu, China.
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2
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Kasai T, Hirai S, Furukawa Y, Misumi K, Takeda T, Goto Y, Takanobu K, Yoneyama K, Yamano S, Senoh H, Umeda Y. Lung carcinogenicity by whole body inhalation exposure to Anatase-type Nano-titanium Dioxide in rats. J Toxicol Sci 2024; 49:359-383. [PMID: 39098045 DOI: 10.2131/jts.49.359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/06/2024]
Abstract
To investigate the carcinogenicity of anatase-type nano-titanium dioxide (aNTiO2), F344/DuCrlCrlj rats were exposed to aNTiO2 aerosol at concentrations of 0, 0.5, 2, and 8 mg/m3. The rats were divided into 2 groups: carcinogenicity study groups were exposed for two years, and satellite study groups were exposed for one year followed by recovery for 1 day, 26 weeks, and 52 weeks after the end of exposure. In the carcinogenicity groups, bronchiolo-alveolar carcinomas were observed in two 8 mg/m3-exposed males, showing an increasing trend by Peto's test. However, this incidence was at the upper limit of JBRC's historical control data. Bronchiolo-alveolar adenomas were observed in 1, 2, 3, and 4 rats of the 0, 0.5, 2, and 8 mg/m3-exposed females and were not statistically significant. However, the incidence in the 8 mg/m3-exposed females exceeded JBRC's historical control data. Therefore, we conclude there is equivocal evidence for the carcinogenicity of aNTiO2 in rats. No lung tumors were observed in the satellite groups. Particle-induced non-neoplastic lesions (alveolar epithelial hyperplasia and focal fibrosis) were observed in exposed males and females in both the carcinogenicity and satellite groups. Increased lung weight and neutrophils of bronchoalveolar lavage fluid were observed in the 8 mg/m3-exposed carcinogenicity groups. The aNTiO2 deposited in the lungs of the satellite group rats was decreased at 26 weeks after the end of exposure compared to 1 day after the end of exposure. At 52 weeks after the end of exposure, the decreased level was the same at 26 weeks after the end of exposure.
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Affiliation(s)
- Tatsuya Kasai
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Shigeyuki Hirai
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Yuske Furukawa
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Kyouhei Misumi
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Tomoki Takeda
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Yuko Goto
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Kenji Takanobu
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Kengo Yoneyama
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Shotaro Yamano
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Hideki Senoh
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
| | - Yumi Umeda
- Japan Bioassay Research Center (JBRC), Japan Organization of Occupational Health and Safety
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Menssen M. The calculation of historical control limits in toxicology: Do's, don'ts and open issues from a statistical perspective. MUTATION RESEARCH. GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2023; 892:503695. [PMID: 37973293 DOI: 10.1016/j.mrgentox.2023.503695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 09/14/2023] [Accepted: 09/16/2023] [Indexed: 11/19/2023]
Abstract
For reporting toxicology studies, the presentation of historical control data and the validation of the concurrent control group with respect to historical control limits have become requirements. However, many regulatory guidelines fail to define how such limits should be calculated and what kind of target value(s) they should cover. Hence, this manuscript is aimed to give a brief review on the methods for the calculation of historical control limits that are in use as well as on their theoretical background. Furthermore, this manuscript is aimed to identify open issues for the use of historical control limits that need to be discussed by the community. It seems that, even after 40 years of discussion, more issues remain open than solved, both, with regard to the available methodology as well as its implementation in user-friendly software. Since several of these topics equally apply to several research fields, this manuscript is addressed to all relevant stakeholders who deal with historical control data obtained from toxicological studies, regardless of their background or field of research.
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Affiliation(s)
- Max Menssen
- Leibniz University Hannover, Institute of Cell Biology and Biophysics, Department of Biostatistics, Herrenäuser Straße 2, 30419 Hannover, Germany.
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4
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Radi ZA, Khan N. Pathophysiology and human cancer risk assessment of pharmaceutical-induced thymoma in carcinogenicity studies. Toxicol Appl Pharmacol 2023; 466:116471. [PMID: 36934859 DOI: 10.1016/j.taap.2023.116471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 03/11/2023] [Accepted: 03/13/2023] [Indexed: 03/19/2023]
Abstract
Thymoma, a tumor of thymic lymphocytes or thymic epithelial cells (TECs), is a common spontaneous tumor in Wistar Han rats, especially in females with up to 18% incidence in controls. In addition to sex, there are rat strain differences in background incidence of thymomas such as Sprague Dawley versus Wistar Han rats. Human thymomas are very rare and without clear differences in incidence between males and females. Immunomodulatory and anti-inflammatory pharmaceutical drug classes, including Janus kinase inhibitors, increase the incidence of benign thymoma in two-year rat carcinogenicity studies. Potential non-genotoxic mechanisms that might contribute to the pathogenesis of thymoma development in one sex (female) Wistar Han rats include: (1) hormonal differences, (2) high proliferation rate of TECs, (3) delayed physiologic thymic involution, and/or (4) significant level of immunosuppression at high doses of a pharmaceutical drug. Factors to consider in the human cancer risk assessment of pharmaceutical-induced thymoma are: the genotoxicity of the test article, sex and strain of rats, exposure safety margins, and pathophysiologic differences and similarities of thymoma between rats and humans. Totality of weight of evidence approach and available data suggest thymomas observed in carcinogenicity studies of pharmaceutical drugs are not relevant for human risk at clinically relevant therapeutic doses.
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Affiliation(s)
- Zaher A Radi
- Pfizer Worldwide Research, Development and Medical, Drug Safety R&D, 1 Portland Street, Cambridge, MA 02140, USA.
| | - Nasir Khan
- Pfizer Worldwide Research, Development and Medical, Drug Safety R&D, Eastern Point Road, Groton, CT 06340, USA
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5
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Wright PSR, Briggs KA, Thomas R, Smith GF, Maglennon G, Mikulskis P, Chapman M, Greene N, Phillips BU, Bender A. Statistical analysis of preclinical inter-species concordance of histopathological findings in the eTOX database. Regul Toxicol Pharmacol 2023; 138:105308. [PMID: 36481279 DOI: 10.1016/j.yrtph.2022.105308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 11/17/2022] [Accepted: 11/25/2022] [Indexed: 12/12/2022]
Abstract
Preclinical inter-species concordance can increase the predictivity of observations to the clinic, potentially reducing drug attrition caused by unforeseen adverse events. We quantified inter-species concordance of histopathological findings and target organ toxicities across four preclinical species in the eTOX database using likelihood ratios (LRs). This was done whilst only comparing findings between studies with similar compound exposure (Δ|Cmax| ≤ 1 log-unit), repeat-dosing duration, and animals of the same sex. We discovered 24 previously unreported significant inter-species associations between histopathological findings encoded by the HPATH ontology. More associations with strong positive concordance (33% LR+ > 10) relative to strong negative concordance (12.5% LR- < 0.1) were identified. Of the top 10 most positively concordant associations, 60% were computed between different histopathological findings indicating potential differences in inter-species pathogenesis. We also observed low inter-species target organ toxicity concordance. For example, liver toxicity concordance in short-term studies between female rats and dogs observed an average LR+ of 1.84, and an average LR- of 0.73. This was corroborated by similarly low concordance between rodents and non-rodents for 75 candidate drugs in AstraZeneca. This work provides new statistically significant associations between preclinical species, but finds that concordance is rare, particularly between the absence of findings.
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Affiliation(s)
- Peter S R Wright
- University of Cambridge, Centre for Molecular Science Informatics, Department of Chemistry, Cambridge, United Kingdom.
| | | | | | - Graham F Smith
- AstraZeneca, Data Science and AI, Clinical Pharmacology and Safety Sciences, R&D, Cambridge, United Kingdom
| | - Gareth Maglennon
- AstraZeneca, Oncology Pathology, Clinical Pharmacology and Safety Sciences, R&D, Melbourn, United Kingdom
| | - Paulius Mikulskis
- AstraZeneca, Imaging and Data Analytics, Clinical Pharmacology & Safety Sciences, R&D, Gothenburg, Sweden
| | - Melissa Chapman
- AstraZeneca, Toxicology, Clinical Pharmacology and Safety Sciences, R&D, Melbourn, United Kingdom
| | - Nigel Greene
- AstraZeneca, Data Science and Artificial Intelligence, Clinical Pharmacology and Safety Sciences, R&D, Boston, MA, USA
| | - Benjamin U Phillips
- AstraZeneca, Data Sciences and Quantitative Biology, Discovery Sciences, Cambridge Biomedical Campus, Cambridge, United Kingdom
| | - Andreas Bender
- University of Cambridge, Centre for Molecular Science Informatics, Department of Chemistry, Cambridge, United Kingdom.
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6
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Elmore SA, Rehg JE, Schoeb TR, Everitt JI, Bolon B. Pathologists' perspective on the study design, analysis, and interpretation of proliferative lesions in lifetime and prenatal rodent carcinogenicity bioassays of aspartame. Food Chem Toxicol 2022; 171:113504. [PMID: 36414169 DOI: 10.1016/j.fct.2022.113504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 10/21/2022] [Accepted: 10/27/2022] [Indexed: 11/21/2022]
Abstract
Aspartame, an artificial sweetener commonly used as a sugar substitute, is currently authorized for use in more than 100 countries. Hundreds of studies, conducted in various countries dating back to the 1970s, have shown that aspartame is safe at real-world exposure levels. Furthermore, multiple human epidemiology studies have provided no indication that consumption of aspartame induces cancer. Given the continued controversy surrounding the Ramazzini Institute's (RI) studies suggesting that aspartame is a carcinogenic hazard in rodents and evaluation by the International Agency for Research on Cancer, this report aims to provide the perspective of experienced pathologists on publicly available pathology data regarding purported proliferative lesions in liver, lung, lymphoid organs, and mammary gland as well as their implications for human risk assessment as reported for three lifetime rodent carcinogenicity bioassays of aspartame conducted at the RI. In the authors' view, flaws in the design, methodology and reporting of the RI aspartame studies limit the utility of the data sets as evidence that this agent represents a carcinogenic hazard. Therefore, all three RI studies, and particularly the accuracy of their pathology diagnoses and interpretations, should be rigorously reviewed by qualified and experienced veterinary toxicologic pathologists in assessing aspartame's carcinogenic risk.
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Affiliation(s)
| | - Jerold E Rehg
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Trenton R Schoeb
- Department of Genetics and Animal Resources Program, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Jeffrey I Everitt
- Department of Pathology, Duke University School of Medicine, Durham, NC, USA
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7
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Mevissen M, Ward JM, Kopp-Schneider A, McNamee JP, Wood AW, Rivero TM, Thayer K, Straif K. Effects of radiofrequency electromagnetic fields (RF EMF) on cancer in laboratory animal studies. ENVIRONMENT INTERNATIONAL 2022; 161:107106. [PMID: 35091376 DOI: 10.1016/j.envint.2022.107106] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Revised: 12/03/2021] [Accepted: 01/18/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND The carcinogenicity of radiofrequency electromagnetic fields (RF EMF) has been evaluated by the International Agency for Research on Cancer (IARC) in 2011. Based on limited evidence of carcinogenicity in humans and in animals, RF EMF were classified as possibly carcinogenic to humans (Group 2B). In 2018, based on a survey amongst RF experts, WHO prioritized six major topics of potential RF EMF related human health effects for systematic reviews. In the current manuscript, we present the protocol for the systematic review of experimental laboratory animal studies (cancer bioassays) on exposure to RF fields on the outcome of cancer in laboratory animals. OBJECTIVE In the framework of WHO's Radiation Program, the aim of this work is to systematically evaluate effects of RF EMF exposure on cancer in laboratory animals. STUDY ELIGIBILITY AND CRITERIA WHO's Handbook (2014) for guideline development will be followed with appropriate adaptation. The selection of eligible studies will be based on Population, Exposures, Comparators, and Outcomes (PECO) criteria. We will include peer-reviewed articles and publicly available reports from government agencies reporting original data about animal cancer bioassays on exposure to RF EMF. The studies are identified by searching the following databases: MEDLINE (PubMed), Science Citation Index Expanded and Emerging Sources Citation Indes (Web of Science), Scopus, and the EMF Portal. No language or year-of-publication restrictions are applied. The methods and results of eligible studies will be presented in accordance with the PRISMA 2020 guidelines. STUDY APPRAISAL METHOD Study evaluation of individual studies will be assessed using a risk of bias (RoB) tool developed by the Office of Health Assessment and Translation (OHAT) with appropriate considerations including sensitivity for evaluating RF EMF exposure in animal cancer bioassays. The final evaluation on the certainty of the evidence on a carcinogenic risk of RF EMF exposure in experimental animals will be performed using the OHAT Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach with appropriate considerations. The protocol has been registered in an open-source repository (PROSPERO). FUNDING The study is partly financially supported by the World Health Organization. No additional funding was provided outside author salaries through their places of employment.
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Affiliation(s)
- Meike Mevissen
- Veterinary Pharmacology & Toxicology, Department of Clinical Research and Veterinary Public Health (DCR-VPH), University of Bern, Bern, Switzerland.
| | | | | | - James P McNamee
- Non-Ionizing Radiation Health Sciences Division, Consumer and Clinical Radiation Protection Bureau, Health Canada, Ottawa, Canada
| | - Andrew W Wood
- Department of Health Sciences and Statistics, Swinburne University of Technology, Hawthorn, Australia
| | - Tania M Rivero
- Medical Library, University Library, University of Bern, Bern, Switzerland
| | - Kristina Thayer
- Center for Public Health and Environmental Assessment, Chemical & Pollutant Assessment Division, US EPA, NC, USA
| | - Kurt Straif
- ISGlobal, Barcelona, Spain; Boston College, MA, USA
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8
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Kluxen FM, Weber K, Strupp C, Jensen SM, Hothorn LA, Garcin JC, Hofmann T. Using historical control data in bioassays for regulatory toxicology. Regul Toxicol Pharmacol 2021; 125:105024. [PMID: 34364928 DOI: 10.1016/j.yrtph.2021.105024] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/21/2021] [Accepted: 07/30/2021] [Indexed: 12/12/2022]
Abstract
Historical control data (HCD) consist of pooled control group responses from bioassays. These data must be collected and are often used or reported in regulatory toxicology studies for multiple purposes: as quality assurance for the test system, to help identify toxicological effects and their effect-size relevance and to address the statistical multiple comparison problem. The current manuscript reviews the various classical and potential new approaches for using HCD. Issues in current practice are identified and recommendations for improved use and discussion are provided. Furthermore, stakeholders are invited to discuss whether it is necessary to consider uncertainty when using HCD formally and statistically in toxicological discussions and whether binary inclusion/exclusion criteria for HCD should be revised to a tiered information contribution to assessments. Overall, the critical value of HCD in toxicological bioassays is highlighted when used in a weight-of-evidence assessment.
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Affiliation(s)
| | | | | | - Signe M Jensen
- Department of Plant and Efoldnvironmental Sciences, University of Copenhagen, Copenhagen, Denmark
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9
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Matsumoto M, Yamano S, Senoh H, Umeda Y, Hirai S, Saito A, Kasai T, Aiso S. Carcinogenicity and chronic toxicity of acrolein in rats and mice by two-year inhalation study. Regul Toxicol Pharmacol 2021; 121:104863. [PMID: 33465397 DOI: 10.1016/j.yrtph.2021.104863] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 01/03/2021] [Accepted: 01/05/2021] [Indexed: 10/22/2022]
Abstract
The carcinogenicity and chronic toxicity of acrolein was examined by whole body inhalation to groups of 50 F344/DuCrlCrlj rats and 50 B6D2F1/Crlj mice of both sexes for two years. The concentration of acrolein was 0, 0.1, 0.5 or 2 ppm (v/v) for male and female rats; and 0, 0.1, 0.4 or 1.6 ppm for male and female mice. Two-year administration of acrolein induced the squamous cell carcinomas in nasal cavity which is rare tumor in one male and two female rats. In females, rhabdomyoma in nasal cavity was observed in four rats exposed to 2 ppm. In mice, since the survival rate of male and female of mice control group were lowered than 25% in late of the administration periods due to renal lesion and/or amyloid deposition, the mice study was terminated at 93rd week in males, and was terminated at 99th week in females. The incidences of adenomas in nasal cavity were observed in 16 females and significantly increased only in female mice. Thus, acrolein is carcinogenic in two species, i.e. rats and mice. Additionally, non-neoplastic nasal cavity lesions in rats and mice were observed.
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Affiliation(s)
- Michiharu Matsumoto
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan.
| | - Shotaro Yamano
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan
| | - Hideki Senoh
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan
| | - Yumi Umeda
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan
| | - Shigeyuki Hirai
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan
| | - Arata Saito
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan
| | - Tatsuya Kasai
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan
| | - Shigetoshi Aiso
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety, Japan
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Klapötke TM, Scharf R, Stierstorfer J, Unger CC. Toxicity Assessment of Energetic Materials by Using the Luminescent Bacteria Inhibition Test. PROPELLANTS EXPLOSIVES PYROTECHNICS 2020. [DOI: 10.1002/prep.202000044] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Thomas M. Klapötke
- Energetic Materials Research Department of Chemistry Ludwig-Maximilian University Munich Butenandtstr. 5–13 (D) D-81377 Munich Germany
| | - Regina Scharf
- Energetic Materials Research Department of Chemistry Ludwig-Maximilian University Munich Butenandtstr. 5–13 (D) D-81377 Munich Germany
| | - Jörg Stierstorfer
- Energetic Materials Research Department of Chemistry Ludwig-Maximilian University Munich Butenandtstr. 5–13 (D) D-81377 Munich Germany
| | - Cornelia C. Unger
- Energetic Materials Research Department of Chemistry Ludwig-Maximilian University Munich Butenandtstr. 5–13 (D) D-81377 Munich Germany
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11
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Matsumoto M, Kasai T, Saito A, Takanobu K, Senoh H, Umeda Y, Kanno J. Carcinogenicity of butyl 2,3-epoxypropyl ether in rats and mice by whole body inhalation for two years. J Toxicol Sci 2020; 45:1-14. [PMID: 31932553 DOI: 10.2131/jts.45.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Butyl 2,3-epoxypropyl ether (CAS No. 2426-08-6, synonym: n-butylglycidyl ether, BGE) was exposed by whole body inhalation to F344 rats and BDF1 mice of both sexes (50 animals per group) 6 hours per day, 5 days per week for 104 weeks at targeted concentrations of 0, 10, 30 or 90 ppm (v/v) for rats and 0, 5, 15 or 45 ppm for mice. In rats, 90 ppm of BGE increased the incidences of nasal squamous cell carcinomas in both sexes. Nasal adenomas and splenic mononuclear cell leukemia were increased in male rats exposed to 30 ppm. Splenic mononuclear cell leukemia was increased in female rats by trend test. Non-neoplastic nasal lesions, such as squamous cell hyperplasia with atypia, squamous cell metaplasia and the inflammation of the respiratory region and atrophy of the olfactory epithelium were increased in both sexes in a dose-dependent manner. In mice, the incidences of histiocytic sarcomas of the uterus in female mice were increased in a dose-dependent manner and the incidences of nasal hemangiomas in both sexes were increased in a dose-dependent manner. Nasal squamous cell carcinoma, a rare tumor, was observed, although not statistically significant, in both sexes. Non-neoplastic lesions such as nodular hyperplasia of the transitional epithelium and cuboidal changes of the respiratory epithelium in the nasal cavity, were increased both in males and females in a dose-dependent manner. The present study demonstrated clear evidence of carcinogenicity of BGE in both rats and mice by the 2-year whole body inhalation exposure.
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Affiliation(s)
- Michiharu Matsumoto
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety
| | - Tatsuya Kasai
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety
| | - Arata Saito
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety
| | - Kenji Takanobu
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety
| | - Hideki Senoh
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety
| | - Yumi Umeda
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety
| | - Jun Kanno
- Japan Bioassay Research Center, Japan Organization of Occupational Health and Safety
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12
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Lee JG, Anh J, Kang GJ, Kim D, Kang Y. Development of an analytical method for simultaneously determining TBBPA and HBCDs in various foods. Food Chem 2020; 313:126027. [DOI: 10.1016/j.foodchem.2019.126027] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2019] [Revised: 11/20/2019] [Accepted: 12/04/2019] [Indexed: 11/29/2022]
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13
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Assessment of Tetrabromobisphenol and Hexabromocyclododecanes exposure and risk characterization using occurrence data in foods. Food Chem Toxicol 2020; 137:111121. [PMID: 31931070 DOI: 10.1016/j.fct.2020.111121] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2019] [Revised: 12/26/2019] [Accepted: 01/06/2020] [Indexed: 11/21/2022]
Abstract
Tetrabromobisphenol A (TBBPA) and Hexabromocyclododecanes (HBCDs) are two of the most used BFRs and they have cumulated in the environment. TBBPA and HBCDs in food were determined and their risks were assessed. The analytical method used was validated in different food categories, and the performance parameters were acceptable based on the criteria of AOAC. Fish and cephalopods were contaminated with TBBPA higher than other foods, and fish contained higher levels of HBCDs than other foods. α-HBCD was the predominant diastereomer in fish and meat and had strong correlations with HBCDs in fish and cephalopods. HBCDs accumulated easier than TBBPA in food. People were exposed to TBBPA from 0.125 ng kg-1 b.w. day-1 to 0.284 ng kg-1 b.w. day-1 and HBCDs from 0.353 ng kg-1 b.w. day-1 to 1.006 ng kg-1 b.w. day-1 via food and air. Food mainly contributed to exposure to TBBPA and HBCDs and vegetables were the main contributors for exposure to TBBPA and HBCDs in food. MOEs for the whole population were over 100, and the risks of exposure to TBBPA and HBCDs from food and the environment were of low concern to public health.
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14
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Cohen SM, Eisenbrand G, Fukushima S, Gooderham NJ, Guengerich FP, Hecht SS, Rietjens IMCM, Bastaki M, Davidsen JM, Harman CL, McGowen MM, Taylor SV. FEMA GRAS assessment of natural flavor complexes: Mint, buchu, dill and caraway derived flavoring ingredients. Food Chem Toxicol 2019; 135:110870. [PMID: 31604112 DOI: 10.1016/j.fct.2019.110870] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 09/18/2019] [Accepted: 10/02/2019] [Indexed: 02/08/2023]
Abstract
In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavor ingredients. NFC flavor materials include a variety of essential oils and botanical extracts. The re-evaluation of NFCs is conducted based on a constituent-based procedure outlined in 2005 and updated in 2018 that evaluates the safety of NFCs for their intended use as flavor ingredients. This procedure is applied in the re-evaluation of the generally recognized as safe (GRAS) status of NFCs with constituent profiles that are dominated by alicyclic ketones such as menthone and carvone, secondary alcohols such as menthol and carveol, and related compounds. The FEMA Expert Panel affirmed the GRAS status of Peppermint Oil (FEMA 2848), Spearmint Oil (FEMA 3032), Spearmint Extract (FEMA 3031), Cornmint Oil (FEMA 4219), Erospicata Oil (FEMA 4777), Curly Mint Oil (FEMA 4778), Pennyroyal Oil (FEMA 2839), Buchu Leaves Oil (FEMA 2169), Caraway Oil (FEMA 2238) and Dill Oil (FEMA 2383) and determined FEMA GRAS status for Buchu Leaves Extract (FEMA 4923), Peppermint Oil, Terpeneless (FEMA 4924) and Spearmint Oil, Terpeneless (FEMA 4925).
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Affiliation(s)
- Samuel M Cohen
- Havlik-Wall Professor of Oncology, Dept. of Pathology and Microbiology, University of Nebraska Medical Center, 983135 Nebraska Medical Center, Omaha, NE, 68198-3135, USA
| | - Gerhard Eisenbrand
- Food Chemistry & Toxicology, University of Kaiserslautern, Kaiserslautern, Germany
| | - Shoji Fukushima
- Japan Bioassay Research Center, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan
| | - Nigel J Gooderham
- Dept. of Metabolism, Digestion, and Reproduction, Imperial College London, Sir Alexander Fleming Building, London, SW7 2AZ, United Kingdom
| | - F Peter Guengerich
- Dept. of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN, 37232-0146, USA
| | - Stephen S Hecht
- Masonic Cancer Center and Dept. of Laboratory Medicine and Pathology, University of Minnesota, MMC 806, 420 Delaware St., S.E., Minneapolis, MN, 55455, USA
| | - Ivonne M C M Rietjens
- Division of Toxicology, Wageningen University, Tuinlaan 5, 6703 HE, Wageningen, the Netherlands
| | - Maria Bastaki
- Flavor and Extract Manufacturers Association, 1101 17th Street NW, Suite 700, Washington, DC, 20036, USA
| | - Jeanne M Davidsen
- Flavor and Extract Manufacturers Association, 1101 17th Street NW, Suite 700, Washington, DC, 20036, USA
| | - Christie L Harman
- Flavor and Extract Manufacturers Association, 1101 17th Street NW, Suite 700, Washington, DC, 20036, USA
| | - Margaret M McGowen
- Flavor and Extract Manufacturers Association, 1101 17th Street NW, Suite 700, Washington, DC, 20036, USA
| | - Sean V Taylor
- Flavor and Extract Manufacturers Association, 1101 17th Street NW, Suite 700, Washington, DC, 20036, USA.
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15
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FEMA GRAS assessment of natural flavor complexes: Citrus-derived flavoring ingredients. Food Chem Toxicol 2018; 124:192-218. [PMID: 30481573 DOI: 10.1016/j.fct.2018.11.052] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 11/19/2018] [Accepted: 11/23/2018] [Indexed: 01/06/2023]
Abstract
In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association (FEMA) initiated a re-evaluation of the safety of over 250 natural flavor complexes (NFCs) used as flavoring ingredients. This publication is the first in a series and summarizes the evaluation of 54 Citrus-derived NFCs using the procedure outlined in Smith et al. (2005) and updated in Cohen et al. (2018) to evaluate the safety of naturally-occurring mixtures for their intended use as flavoring ingredients. The procedure relies on a complete chemical characterization of each NFC intended for commerce and organization of each NFC's chemical constituents into well-defined congeneric groups. The safety of the NFC is evaluated using the well-established and conservative threshold of toxicological concern (TTC) concept in addition to data on absorption, metabolism and toxicology of members of the congeneric groups and the NFC under evaluation. As a result of the application of the procedure, 54 natural flavor complexes derived from botanicals of the Citrus genus were affirmed as generally recognized as safe (GRAS) under their conditions of intended use as flavoring ingredients based on an evaluation of each NFC and the constituents and congeneric groups therein.
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16
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Bastaki M, Aubanel M, Bauter M, Cachet T, Demyttenaere J, Diop MM, Harman CL, Hayashi SM, Krammer G, Li X, Llewellyn C, Mendes O, Renskers KJ, Schnabel J, Smith BP, Taylor SV. Absence of renal adverse effects from β-myrcene dietary administration in OECD guideline-compliant subchronic toxicity study. Food Chem Toxicol 2018; 120:222-229. [DOI: 10.1016/j.fct.2018.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 06/22/2018] [Accepted: 07/02/2018] [Indexed: 01/22/2023]
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17
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Galwey NW. Supplementation of a clinical trial by historical control data: is the prospect of dynamic borrowing an illusion? Stat Med 2016; 36:899-916. [DOI: 10.1002/sim.7180] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 10/19/2016] [Accepted: 11/01/2016] [Indexed: 12/13/2022]
Affiliation(s)
- N. W. Galwey
- GlaxoSmithKline R&D; Medicines Research Centre; Stevenage Hertfordshire U.K
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18
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Cohen SM, Goodman JI, Klaunig JE, Arnold LL. Response to Druwe and Burgoon, 2016 Letter to the Editor in Archives of Toxicology. Arch Toxicol 2016; 91:999-1000. [PMID: 27830267 DOI: 10.1007/s00204-016-1884-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 11/02/2016] [Indexed: 11/30/2022]
Affiliation(s)
| | | | | | - Lora L Arnold
- University of Nebraska Medical Center, Omaha, NE, USA
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19
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Jackson CD, Blackwell BN. 2-year Toxicity Study of Doxylamine Succinate in the Fischer 344 Rat. ACTA ACUST UNITED AC 2016. [DOI: 10.3109/10915819309140617] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Doxylamine succinate, a commonly used antihistamine, was administered as an admixture in the feed to groups of male and female Fischer 344 rats at dose levels of 0, 500, 1000, and 2000 parts per million (ppm) (based on free amine) for 65 weeks (9 per group) or two years (48 per group). There were no significant treatment-related differences in survival in either sex. Compared to controls, final body weights of rats in the 2000 ppm group were reduced 8.4% and 22.8% in males and females, respectively. Treatment-related, non-neoplastic lesions were found primarily in the liver and parotid salivary gland. Liver lesions consisted of fatty change and degeneration in both sexes; hyperplasia (resulting from degeneration due to leukemia) and atypical cells in males; and hypertrophy, chronic inflammation, and mixed cell foci in females. Both sexes exhibited a treatment-related increase in cytoplasmic alteration in the salivary glands. Liver neoplasms were found only in the highest dose group of male rats. The trend test was significant (p ≤ 0.05) for increased incidence of hepatocellular adenoma and carcinoma with increasing doses of doxylamine, but the increased incidence of either lesion in the high dose group was not significant compared to that in controls. However, when animals with carcinoma or adenoma were combined, the trend test remained significant (p ≤ 0.01), and the incidence of the highest dose group was significantly increased (p ≤ 0.05) over that in controls. No treatment-related increase in neoplasms was found in females, but doxylamine produced a marked dose-related decrease in mammary fibroadenomas. Although not statistically significant, a very rare pineal gland tumor was found in 1 male and 1 female rat in the 2000 ppm group.
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Affiliation(s)
- Carlton D. Jackson
- Division of Nutritional Toxicology National Center for Toxicological Research 1 NCTR Drive Jefferson, AR 72079
| | - Boon-Nam Blackwell
- Division of Nutritional Toxicology National Center for Toxicological Research 1 NCTR Drive Jefferson, AR 72079
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20
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Affiliation(s)
- J. K. Haseman
- Division of Biometry and Risk Assessment, National Institute of Environmental Health Sciences Research Triangle Park, North Carolina
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21
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Portier CJ, Armstrong BK, Baguley BC, Baur X, Belyaev I, Bellé R, Belpoggi F, Biggeri A, Bosland MC, Bruzzi P, Budnik LT, Bugge MD, Burns K, Calaf GM, Carpenter DO, Carpenter HM, López-Carrillo L, Clapp R, Cocco P, Consonni D, Comba P, Craft E, Dalvie MA, Davis D, Demers PA, De Roos AJ, DeWitt J, Forastiere F, Freedman JH, Fritschi L, Gaus C, Gohlke JM, Goldberg M, Greiser E, Hansen J, Hardell L, Hauptmann M, Huang W, Huff J, James MO, Jameson CW, Kortenkamp A, Kopp-Schneider A, Kromhout H, Larramendy ML, Landrigan PJ, Lash LH, Leszczynski D, Lynch CF, Magnani C, Mandrioli D, Martin FL, Merler E, Michelozzi P, Miligi L, Miller AB, Mirabelli D, Mirer FE, Naidoo S, Perry MJ, Petronio MG, Pirastu R, Portier RJ, Ramos KS, Robertson LW, Rodriguez T, Röösli M, Ross MK, Roy D, Rusyn I, Saldiva P, Sass J, Savolainen K, Scheepers PTJ, Sergi C, Silbergeld EK, Smith MT, Stewart BW, Sutton P, Tateo F, Terracini B, Thielmann HW, Thomas DB, Vainio H, Vena JE, Vineis P, Weiderpass E, Weisenburger DD, Woodruff TJ, Yorifuji T, Yu IJ, Zambon P, Zeeb H, Zhou SF. Differences in the carcinogenic evaluation of glyphosate between the International Agency for Research on Cancer (IARC) and the European Food Safety Authority (EFSA). J Epidemiol Community Health 2016; 70:741-5. [PMID: 26941213 PMCID: PMC4975799 DOI: 10.1136/jech-2015-207005] [Citation(s) in RCA: 79] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
| | | | | | - Xaver Baur
- Charité University Medicine Berlin, Berlin, Germany
| | - Igor Belyaev
- Cancer Research Institute, Bratislava, Slovak Republic
| | - Robert Bellé
- Sorbonne Universités, UPMC Univ Paris 06, UMR8227, Roscoff, France
| | | | - Annibale Biggeri
- Institute for Cancer Prevention and Research, University of Florence, Italy
| | | | - Paolo Bruzzi
- National Cancer Research Institute, San Martino—IST Hospital, Genoa, Italy
| | | | - Merete D Bugge
- STAMI, National Institute of Occupational Health, Oslo, Norway
| | | | - Gloria M Calaf
- Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile
| | - David O Carpenter
- Institute for Health and the Environment, University at Albany, Rensselaer, New York, USA
| | | | | | - Richard Clapp
- Boston University School of Public Health, Boston, Massachusetts, USA
| | - Pierluigi Cocco
- Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy
| | - Dario Consonni
- Department of Preventive Medicine, Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Pietro Comba
- Department of Environment and Primary Prevention, IstitutoSuperiore di Sanità, Rome, Italy
| | - Elena Craft
- Environmental Defense Fund, Austin, Texas, USA
| | - Mohamed Aqiel Dalvie
- Center for Environmental and Occupational Health, University of Cape Town, Cape Town, South Africa
| | - Devra Davis
- Environmental Health Trust, Jackson Hole, Wyoming, USA and The Hebrew University Hadassah School of Medicine, Jerusalem, Israel.
| | - Paul A Demers
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Anneclaire J De Roos
- Department of Environmental and Occupational Health, Drexel University, Philadelphia, Pennsylvania, USA
| | - Jamie DeWitt
- Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | | | | | - Lin Fritschi
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Caroline Gaus
- Department of Environmental Toxicology, The University of Queensland, Brisbane, Australia
| | - Julia M Gohlke
- Department of Population Health Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | | | | | - Johnni Hansen
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | | | - Michael Hauptmann
- Biostatistics Branch, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Wei Huang
- Faculty of Department of Occupational and Environmental Health, Peking Univ School of Public Health, Beijing, China
| | - James Huff
- National Institute for Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | | | - C W Jameson
- CWJ Consulting, LLC, Cape Coral, Florida, USA
| | - Andreas Kortenkamp
- Institute of Environment, Health and Societies, Brunel University London, London, UK
| | | | - Hans Kromhout
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Marcelo L Larramendy
- National Council of Scientific and Technological Research, National University of La Plata, Argentina
| | - Philip J Landrigan
- Arnhold Institute for Global Health, Icahn School of Medicine at Mount Sinai,New York, USA
| | - Lawrence H Lash
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | | | - Charles F Lynch
- Department of Epidemiology, University of Iowa, Iowa City, Iowa, USA
| | - Corrado Magnani
- Cancer Epidemiology Unit, University of Eastern Piedmont, Novara, Italy
| | | | | | - Enzo Merler
- Department of Prevention, Occupational Health Unit, National Health Service, Padua, Italy
| | | | - Lucia Miligi
- Occupational and Environmental Epidemiology Unit, ISPO-Cancer Prevention and Research Institute, Florence, Italy
| | - Anthony B Miller
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Dario Mirabelli
- Unit of Cancer Epidemiology, University of Turin and CPO-Piemonte, Torino, Italy
| | - Franklin E Mirer
- Department of Environmental and Occupational Health Sciences, City University of New York School of Public Health, USA
| | - Saloshni Naidoo
- School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa
| | - Melissa J Perry
- Department of Environmental and Occupational Health, Milken Institute School of Public Health, The George Washington University, Washington DC, USA
| | - Maria Grazia Petronio
- Health and Environment-Department of Prevention, Local Health Authority-Empoli, Florence, Italy
| | - Roberta Pirastu
- Department of Biology and Biotechnology “Charles Darwin”, Sapienza Rome University, Italy
| | - Ralph J Portier
- Department of Environmental Sciences, School of the Coast & Environment, Louisiana State University, Baton Rouge, Los Angeles, USA
| | - Kenneth S Ramos
- Center for Applied Genetics and Genomic Medicine, University of Arizona Health Sciences, Tucson, Arizona, USA
| | - Larry W Robertson
- Iowa Superfund Research Program and the Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, Iowa, USA
| | - Theresa Rodriguez
- Center for Research in Health, Work and Environment (CISTA), National Autonomous University of Nicaragua (UNAN-León), León, Nicaragua
| | - Martin Röösli
- Swiss Tropical and Public Health Institute, Associated Institute of the University of Basel, Basel, Switzerland
| | - Matt K Ross
- College of Veterinary Medicine, Mississippi State University, Mississippi State, USA
| | - Deodutta Roy
- Department of Environmental and Occupational Health, Florida International University, Miami, Florida, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Paulo Saldiva
- Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Jennifer Sass
- Natural Resources Defense Council and George Washington University, Washington DC, USA
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Helsinki, Finland
| | - Paul T J Scheepers
- Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Consolato Sergi
- Department of Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Ellen K Silbergeld
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Martyn T Smith
- School of Public Health, University of California, Berkeley, California, USA
| | - Bernard W Stewart
- Faculty of Medicine, University of New South Wales, Randwick, New South WalesAustralia
| | - Patrice Sutton
- Program on Reproductive Health and the Environment, University of California, San Francisco, California, USA
| | - Fabio Tateo
- Istituto di Geosceinze e Georisorse (CNR), Padova, Italy
| | | | - Heinz W Thielmann
- German Cancer Research Center, Heidelberg and Faculty of Pharmacy, Heidelberg University, Germany
| | - David B Thomas
- Fred Hutchinson Cancer Research Center, University of Washington, Seattle, Washington, USA
| | - Harri Vainio
- Faculty of Public Health, Kuwait University, Kuwait City, Kuwait
| | - John E Vena
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Paolo Vineis
- Department of Environmental Epidemiology, Imperial College London, London, UK
| | - Elisabete Weiderpass
- Department of Research, Cancer Registry of Norway, Institute of Population-Based Cancer Research, Oslo, Norway; Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, The Arctic University of Norway, Tromsø, Norway; Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; and Genetic Epidemiology Group, Folkhälsan Research Center, Helsinki, Finland.
| | | | - Tracey J Woodruff
- Program on Reproductive Health and the Environment, University of California, San Francisco, USA
| | | | - Il Je Yu
- Institute of Nanoproduct Safety Research, Hoseo University, Asan, The Republic of Korea
| | | | - Hajo Zeeb
- Department of Prevention and Evaluation, Leibniz-Institute for Prevention Research and Epidemiology, Bremen, Germany
| | - Shu-Feng Zhou
- College of Pharmacy, University of South Florida, Tampa, Florida, USA
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22
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Burns-Naas LA, Zorbas M, Jessen B, Evering W, Stevens G, Ivett JL, Ryan TE, Cook JC, Capen CC, Chen M, Furman G, Theiss JC, Webber S, Wu E, Shetty B, Gasser R, McClain RM. Increase in thyroid follicular cell tumors in nelfinavir-treated rats observed in a 2-year carcinogenicity study is consistent with a rat-specific mechanism of thyroid neoplasia. Hum Exp Toxicol 2016; 24:643-54. [PMID: 16408618 DOI: 10.1191/0960327105ht568oa] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The carcinogenic potential of nelfinavir mesylate (nelfinavir) was evaluated in a 2-year oral (gavage) study on Sprague-Dawley rats at dose levels of 0 (control), 0 (vehicle control), 100, 300 and 1000 mg/kg per day. At the end of the treatment, increased incidences of thyroid follicular cell hyperplasia and neoplasms were observed at 300 (males) and 1000 mg/kg per day (both sexes). There were no other treatment-related effects and no tumors at other sites. Results from previous studies indicated a number of effects in the liver and thyroid, as well as metabolic profiles that suggested nelfinavir might cause thyroid hyperplasia/neoplasia secondary to hormone imbalance by altering thyroid hormone disposition. To investigate this hypothesis, the effects of nelfinavir on gene expression in rat hepatocytes and liver slices (in vitro), thyroxine plasma clearance, and thyroid gland function were evaluated. Compared to controls, gene expression analyses demonstrated an increased expression of glucuronyltransferase (UDPGT) and CYP450 3A1 in nelfinavir-treated rat hepatocytes and liver slices. In rats treated with nelfinavir (1000 mg/kg per day) for 4 weeks, liver weights and centrilobular hepatocellular hypertrophy were increased and minimal to mild diffuse thyroid follicular cell hypertrophy and follicular cell hyperplasia were evident in the thyroid gland. Thyroid-stimulating hormone (TSH) levels were significantly increased (three-fold), while tri-iodothyronine (T3)/tetraiodothyronine (T4) and reverse T3(rT3) levels were unchanged, indicating that a compensated state to maintain homeostasis of T3/T4 had been achieved. Plasma 125I-thyroxine clearance was increased and the plasma thyroxine AUC0 48 was decreased (24%) compared to control. In conclusion, these data indicate that thyroid neoplasms observed in the nelfinavir-treated rats were secondary to thyroid hormone imbalance. Increased thyroxine clearance contributes to the effects of nelfinavir on thyroid gland function and is probably a result of UDPGT induction that leads to elevated TSH levels in the rat and eventual thyroid neoplasia. These results are consistent with a well-recognized rat-specific mechanism for thyroid neoplasms.
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Affiliation(s)
- L A Burns-Naas
- Pfizer Global Research and Development, San Diego, CA 92121, USA.
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23
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Baldrick P. Carcinogenicity Evaluation: Comparison of Tumor Data from Dual Control Groups in the Sprague–Dawley Rat. Toxicol Pathol 2016; 33:283-91. [PMID: 15902972 DOI: 10.1080/019262390908371] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Following recent clarification in Europe that a single control group is now acceptable for rodent carcinogenicity studies, the use of dual controls may be reduced or disappear. To date, virtually nothing has been published on whether this latter situation has improved the identification of tumorigenic risk potential in these studies. In this paper, the results of 13 rat carcinogenicity studies, performed between 1991 and 2002, with 2 control groups, are presented. Although no major differences in tumor incidences between these dual control groups were found, some interstudy variation occurred. In cases where a notable difference was seen, the use of 2 control groups, as well as robust, contemporary background data, allowed an easier interpretation of findings in drug-treated groups. Thus, the continued use of dual control groups has a vital role in the assessment of tumoriogenic risk. The paper also presents an update on survival, on the range and extent of background spontaneous neoplasms, and comments on genetic drift in this commonly used rat strain.
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Affiliation(s)
- Paul Baldrick
- Scientific and Regulatory Consulting, Covance Laboratories Ltd., Otley Road, Harrogate, HG3 1PY North Yorkshire, United Kingdom.
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24
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Baldrick P, Reeve L. Carcinogenicity Evaluation: Comparison of Tumor Data from Dual Control Groups in the CD–1 Mouse. Toxicol Pathol 2016; 35:562-9. [PMID: 17562489 DOI: 10.1080/01926230701347330] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Current regulatory thinking allows for the use of single control groups for rodent carcinogenicity testing although there has been a trend until recently to use dual control groups. To date, virtually nothing has been published on whether a shift from dual to single control groups will affect the identification of tumorigenic risk potential in these studies. A recent evaluation of dual control carcinogenicity data in the rat (Baldrick, Toxicol Pathol 2005, 33: 283–291) showed that although no major differences in tumor incidences between the control groups were found, some interstudy variation occurred and in cases were a notable difference was seen, the use of 2 control groups, as well as robust, contemporary background data, allowed an easier interpretation of findings in drug-treated groups. In this paper, the results of 10 mouse carcinogenicity studies, performed between 1991 and 2004, with 2 control groups, are presented. As in the rat, interstudy variation was seen and in some cases, the use of dual control groups assisted in the tumor risk assessment. Thus, the continued use of 2 control groups can have a vital role in mouse carcinogenicity studies. The paper also presents an update on survival, on the range and extent of background spontaneous neoplasms and comments on genetic drift in this commonly used mouse strain.
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Affiliation(s)
- Paul Baldrick
- Scientific and Regulatory Consulting, Covance Laboratories Ltd., England, HG3 1PY, United Kingdom.
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25
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Portier CJ, Armstrong BK, Baguley BC, Baur X, Belyaev I, Bellé R, Belpoggi F, Biggeri A, Bosland MC, Bruzzi P, Budnik LT, Bugge MD, Burns K, Calaf GM, Carpenter DO, Carpenter HM, López-Carrillo L, Clapp R, Cocco P, Consonni D, Comba P, Craft E, Dalvie MA, Davis D, Demers PA, De Roos AJ, DeWitt J, Forastiere F, Freedman JH, Fritschi L, Gaus C, Gohlke JM, Goldberg M, Greiser E, Hansen J, Hardell L, Hauptmann M, Huang W, Huff J, James MO, Jameson CW, Kortenkamp A, Kopp-Schneider A, Kromhout H, Larramendy ML, Landrigan PJ, Lash LH, Leszczynski D, Lynch CF, Magnani C, Mandrioli D, Martin FL, Merler E, Michelozzi P, Miligi L, Miller AB, Mirabelli D, Mirer FE, Naidoo S, Perry MJ, Petronio MG, Pirastu R, Portier RJ, Ramos KS, Robertson LW, Rodriguez T, Röösli M, Ross MK, Roy D, Rusyn I, Saldiva P, Sass J, Savolainen K, Scheepers PTJ, Sergi C, Silbergeld EK, Smith MT, Stewart BW, Sutton P, Tateo F, Terracini B, Thielmann HW, Thomas DB, Vainio H, Vena JE, Vineis P, Weiderpass E, Weisenburger DD, Woodruff TJ, Yorifuji T, Yu IJ, Zambon P, Zeeb H, Zhou SF. Differences in the carcinogenic evaluation of glyphosate between the International Agency for Research on Cancer (IARC) and the European Food Safety Authority (EFSA). J Epidemiol Community Health 2016. [PMID: 26941213 DOI: 10.1136/jech-2015-207005.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
| | | | | | - Xaver Baur
- Charité University Medicine Berlin, Berlin, Germany
| | - Igor Belyaev
- Cancer Research Institute, Bratislava, Slovak Republic
| | - Robert Bellé
- Sorbonne Universités, UPMC Univ Paris 06, UMR8227, Roscoff, France
| | | | - Annibale Biggeri
- Institute for Cancer Prevention and Research, University of Florence, Italy
| | | | - Paolo Bruzzi
- National Cancer Research Institute, San Martino-IST Hospital, Genoa, Italy
| | | | - Merete D Bugge
- STAMI, National Institute of Occupational Health, Oslo, Norway
| | | | - Gloria M Calaf
- Instituto de Alta Investigación, Universidad de Tarapacá, Arica, Chile
| | - David O Carpenter
- Institute for Health and the Environment, University at Albany, Rensselaer, New York, USA
| | | | | | - Richard Clapp
- Boston University School of Public Health, Boston, Massachusetts, USA
| | - Pierluigi Cocco
- Department of Public Health, Clinical and Molecular Medicine, University of Cagliari, Cagliari, Italy
| | - Dario Consonni
- Department of Preventive Medicine, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Pietro Comba
- Department of Environment and Primary Prevention, IstitutoSuperiore di Sanità, Rome, Italy
| | - Elena Craft
- Environmental Defense Fund, Austin, Texas, USA
| | - Mohamed Aqiel Dalvie
- Center for Environmental and Occupational Health, University of Cape Town, Cape Town, South Africa
| | - Devra Davis
- Environmental Health Trust, Jackson Hole, Wyoming, USA and The Hebrew University Hadassah School of Medicine, Jerusalem, Israel
| | - Paul A Demers
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Anneclaire J De Roos
- Department of Environmental and Occupational Health, Drexel University, Philadelphia, Pennsylvania, USA
| | - Jamie DeWitt
- Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | | | | | - Lin Fritschi
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Caroline Gaus
- Department of Environmental Toxicology, The University of Queensland, Brisbane, Australia
| | - Julia M Gohlke
- Department of Population Health Sciences, Virginia Tech, Blacksburg, Virginia, USA
| | | | | | - Johnni Hansen
- Danish Cancer Society Research Center, Copenhagen, Denmark
| | | | - Michael Hauptmann
- Biostatistics Branch, Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Wei Huang
- Faculty of Department of Occupational and Environmental Health, Peking Univ School of Public Health, Beijing, China
| | - James Huff
- National Institute for Environmental Health Sciences, Research Triangle Park, North Carolina, USA
| | | | - C W Jameson
- CWJ Consulting, LLC, Cape Coral, Florida, USA
| | - Andreas Kortenkamp
- Institute of Environment, Health and Societies, Brunel University London, London, UK
| | | | - Hans Kromhout
- Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands
| | - Marcelo L Larramendy
- National Council of Scientific and Technological Research, National University of La Plata, Argentina
| | - Philip J Landrigan
- Arnhold Institute for Global Health, Icahn School of Medicine at Mount Sinai, New York, USA
| | - Lawrence H Lash
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, USA
| | | | - Charles F Lynch
- Department of Epidemiology, University of Iowa, Iowa City, Iowa, USA
| | - Corrado Magnani
- Cancer Epidemiology Unit, University of Eastern Piedmont, Novara, Italy
| | | | | | - Enzo Merler
- Department of Prevention, Occupational Health Unit, National Health Service, Padua, Italy
| | | | - Lucia Miligi
- Occupational and Environmental Epidemiology Unit, ISPO-Cancer Prevention and Research Institute, Florence, Italy
| | - Anthony B Miller
- Dalla Lana School of Public Health, University of Toronto, Canada
| | - Dario Mirabelli
- Unit of Cancer Epidemiology, University of Turin and CPO-Piemonte, Torino, Italy
| | - Franklin E Mirer
- Department of Environmental and Occupational Health Sciences, City University of New York School of Public Health, USA
| | - Saloshni Naidoo
- School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa
| | - Melissa J Perry
- Department of Environmental and Occupational Health, Milken Institute School of Public Health, The George Washington University, Washington DC, USA
| | - Maria Grazia Petronio
- Health and Environment-Department of Prevention, Local Health Authority-Empoli, Florence, Italy
| | - Roberta Pirastu
- Department of Biology and Biotechnology "Charles Darwin", Sapienza Rome University, Italy
| | - Ralph J Portier
- Department of Environmental Sciences, School of the Coast & Environment, Louisiana State University, Baton Rouge, Los Angeles, USA
| | - Kenneth S Ramos
- Center for Applied Genetics and Genomic Medicine, University of Arizona Health Sciences, Tucson, Arizona, USA
| | - Larry W Robertson
- Iowa Superfund Research Program and the Interdisciplinary Graduate Program in Human Toxicology, University of Iowa, Iowa City, Iowa, USA
| | - Theresa Rodriguez
- Center for Research in Health, Work and Environment (CISTA), National Autonomous University of Nicaragua (UNAN-León), León, Nicaragua
| | - Martin Röösli
- Swiss Tropical and Public Health Institute, Associated Institute of the University of Basel, Basel, Switzerland
| | - Matt K Ross
- College of Veterinary Medicine, Mississippi State University, Mississippi State, USA
| | - Deodutta Roy
- Department of Environmental and Occupational Health, Florida International University, Miami, Florida, USA
| | - Ivan Rusyn
- Department of Veterinary Integrative Biosciences, Texas A&M University, College Station, Texas, USA
| | - Paulo Saldiva
- Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | - Jennifer Sass
- Natural Resources Defense Council and George Washington University, Washington DC, USA
| | - Kai Savolainen
- Nanosafety Research Centre, Finnish Institute of Occupational Health, Helsinki, Finland
| | - Paul T J Scheepers
- Radboud Institute for Health Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Consolato Sergi
- Department of Pathology, University of Alberta, Edmonton, Alberta, Canada
| | - Ellen K Silbergeld
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | - Martyn T Smith
- School of Public Health, University of California, Berkeley, California, USA
| | - Bernard W Stewart
- Faculty of Medicine, University of New South Wales, Randwick, New South Wales Australia
| | - Patrice Sutton
- Program on Reproductive Health and the Environment, University of California, San Francisco, California, USA
| | - Fabio Tateo
- Istituto di Geosceinze e Georisorse (CNR), Padova, Italy
| | | | - Heinz W Thielmann
- German Cancer Research Center, Heidelberg and Faculty of Pharmacy, Heidelberg University, Germany
| | - David B Thomas
- Fred Hutchinson Cancer Research Center, University of Washington, Seattle, Washington, USA
| | - Harri Vainio
- Faculty of Public Health, Kuwait University, Kuwait City, Kuwait
| | - John E Vena
- Department of Public Health Sciences, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Paolo Vineis
- Department of Environmental Epidemiology, Imperial College London, London, UK
| | - Elisabete Weiderpass
- Department of Research, Cancer Registry of Norway, Institute of Population-Based Cancer Research, Oslo, Norway; Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, The Arctic University of Norway, Tromsø, Norway; Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden; and Genetic Epidemiology Group, Folkhälsan Research Center, Helsinki, Finland
| | | | - Tracey J Woodruff
- Program on Reproductive Health and the Environment, University of California, San Francisco, USA
| | | | - Il Je Yu
- Institute of Nanoproduct Safety Research, Hoseo University, Asan, The Republic of Korea
| | | | - Hajo Zeeb
- Department of Prevention and Evaluation, Leibniz-Institute for Prevention Research and Epidemiology, Bremen, Germany
| | - Shu-Feng Zhou
- College of Pharmacy, University of South Florida, Tampa, Florida, USA
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Matsumoto M, Kano H, Suzuki M, Katagiri T, Umeda Y, Fukushima S. Carcinogenicity and chronic toxicity of hydrazine monohydrate in rats and mice by two-year drinking water treatment. Regul Toxicol Pharmacol 2016; 76:63-73. [PMID: 26774757 DOI: 10.1016/j.yrtph.2016.01.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2015] [Revised: 12/14/2015] [Accepted: 01/10/2016] [Indexed: 10/01/2022]
Abstract
The carcinogenicity and chronic toxicity of hydrazine monohydrate was examined by administrating hydrazine monohydrate in drinking water to groups of 50 F344/DuCrj rats and 50 Crj:BDF1 mice of both sexes for two years. The drinking water concentration of hydrazine monohydrate was 0, 20, 40 or 80 ppm (wt/wt) for male and female rats and male mice; and 0, 40, 80 or 160 ppm for female mice. Survival rates of each group of males and females rats and mice were similar to the respective controls, except female rats administered 80 ppm. Two-year administration of hydrazine monohydrate produced an increase in the incidences of hepatocellular adenomas and carcinomas in rats of both sexes along with hepatic foci. In mice, the incidences of hepatocellular adenomas and carcinomas were increased in females, and significantly increased incidences of hepatocellular adenomas in females administered 160 ppm were observed. Thus, hydrazine monohydrate is carcinogenic in two species, rats and mice. Additionally, non-neoplastic renal lesions in rats and mice and non-neoplastic nasal lesions in mice were observed.
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Affiliation(s)
- Michiharu Matsumoto
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan.
| | - Hirokazu Kano
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan
| | - Masaaki Suzuki
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan
| | - Taku Katagiri
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan
| | - Yumi Umeda
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan
| | - Shoji Fukushima
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445 Hirasawa, Hadano, Kanagawa, 257-0015, Japan
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Response to the Waalkes et al., Letter to the editor concerning our "letter to the editor, Re: Lung tumors in mice induced by "whole-life" inorganic arsenic exposure at human relevant doses, Waalkes et al., Arch Toxicol, 2014". Arch Toxicol 2015; 89:2167-8. [PMID: 26449479 DOI: 10.1007/s00204-015-1614-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 09/30/2015] [Indexed: 12/15/2022]
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Spontaneous lesions in endocrine glands of experimental Wistar rats and beagle dogs. ACTA ACUST UNITED AC 2015; 68:1-13. [PMID: 26414849 DOI: 10.1016/j.etp.2015.09.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 08/25/2015] [Accepted: 09/08/2015] [Indexed: 11/21/2022]
Abstract
A retrospective analysis was undertaken at Zydus Research Centre to understand the incidences of spontaneous lesions in endocrine glands of Wistar rats and beagle dogs. The data from a total of 841 Wistar rats (418 males and 423 females) and 144 beagle dogs (72 males and 72 females) was used from placebo/vehicle treated control group of different non-clinical toxicity studies. The lesions in various endocrine glands were classified according to the species and age of the animals at termination of study. Among the endocrine glands, the highest numbers (types) of spontaneous lesions were observed in adrenal glands followed in descending order by pituitary, thyroid, endocrine pancreas and parathyroid glands in Wistar rats. In beagle dogs, highest numbers (types) of spontaneous lesions were seen in adrenals followed by thyroid, endocrine pancreas, pituitary and parathyroid gland. In adrenal glands of Wistar rats, the incidences of cortical cell vacuolation, hemorrhages and hemangiectasis/peliosis were increased with age. Incidence of peliosis at ∼110 weeks of age was higher in female rats. Among the proliferative lesions in rats, higher incidences of cortical cell hyperplasia was observed followed by medullary hyperplasia, complex pheochromocytoma, cortical cell adenoma and cortical adenocarcinoma. In beagle dogs, the incidences of hemangiectasis and cortical cell vacuolation in adrenal glands were higher in 18-21 months aged dogs in both the sexes as compared to 10-12 months of age. In pituitary gland, the incidences of cystic changes were higher in older rats and dogs and the incidences were more in beagles as compared to rats. In thyroid glands, C-cell (parafollicular cells) hyperplasia/complex was observed more frequently in both the species. Few incidences of cystic changes were observed in parathyroid of 18-21 months aged beagle dogs. In endocrine pancreas, few incidences of islet-cell vacuolation, atrophy and hyperplasia were observed in both the species. The Islet cell hyperplasia was found to be more frequent in male rats at ∼110 weeks of age.
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Takanobu K, Aiso S, Umeda Y, Senoh H, Saito M, Katagiri T, Ikawa N, Ishikawa H, Mine T, Take M, Haresaku M, Matsumoto M, Fukushima S. [Background data of spontaneous tumors in F344/DuCrlCrlj rats]. SANGYŌ EISEIGAKU ZASSHI = JOURNAL OF OCCUPATIONAL HEALTH 2015; 57:85-96. [PMID: 25753608 DOI: 10.1539/sangyoeisei.e14006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
INTRODUCTION We investigated the 2-year survival rate and incidence of spontaneous tumors in F344/DuCrlCrlj rats used in carcinogenicity studies of chemical substances. Records for animals used in the control groups of carcinogenicity studies which were conducted during the last 10 years were obtained from the database of the Japan Bioassay Research Center (JBRC). Six hundred ninety-nine males and 550 females were used in 14 and 11 inhalation studies, respectively, and 500 animals of each sex were used in 10 male and 10 female oral studies. METHODS In each study, SPF (specific pathogen free) animals were housed for 2 years (104 weeks) as control groups in the carcinogenicity studies. All animals underwent necropsy and histopathological examination. Each study was conducted in accordance with the Good Laboratory Practice. RESULTS The incidence of interstitial cell tumors was highest in both inhalation studies and oral studies (inhalation studies 86.1%, oral studies 68.6%). Tumors which had an incidence of 6% or higher were adenoma of the pituitary, C-cell adenoma of the thyroid, and mononuclear cell leukemia (LGL leukemia) of the spleen in male and female rats; fibroma of the subcutaneous tissue, adrenal pheochromocytoma, and islet cell adenoma of the pancreas in male rats; and endometrial stromal polyps and fibroadenoma of the mammary gland in female rats. Tumors other than the above had rare incidence rates. A clear difference in the incidence of spontaneous tumors was not observed between the inhalation and oral studies. The incidences of spontaneous tumors in control groups of previous oral studies are similar to our findings. There are no other reports of the spontaneous tumor incidence in the control groups of inhalation studies using F344/DuCrlCrlj rats. The 2-year survival rate was about 77% in both the inhalation and oral studies, and a gender difference was not observed. The F344/DuCrlCrlj rats used at JBRC had a higher 2-year survival rate than F344/N rats. This difference is possibly due to the low incidence of LGL leukemia in the F344/DuCrlCrlj rat. CONCLUSIONS The incidences of spontaneous tumors in F344/DuCrlCrlj rats used in control groups of both inhalation and oral studies during the last 10 years at JBRC are similar to each other and similar to those reported in other studies. This is the first report on the incidence of spontaneous tumors in inhalation studies and contributes to the toxicological evaluation of studies using F344/DuCrlCrlj rats.
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Affiliation(s)
- Kenji Takanobu
- Japan Bioassay Research Center, Japan Industrial Safety and Health Association, 2445, Hirasawa, Hadano, Kanagawa 257-0015, Japan
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Brayton CF, Treuting PM, Ward JM. Pathobiology of aging mice and GEM: background strains and experimental design. Vet Pathol 2014; 49:85-105. [PMID: 22215684 DOI: 10.1177/0300985811430696] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The use of induced and spontaneous mutant mice and genetically engineered mice (and combinations thereof) to study cancers and other aging phenotypes to advance improved functional human life spans will involve studies of aging mice. Genetic background contributes to pathology phenotypes and to causes of death as well as to longevity. Increased recognition of expected phenotypes, experimental variables that influence phenotypes and research outcomes, and experimental design options and rationales can maximize the utility of genetically engineered mice (GEM) models to translational research on aging. This review aims to provide resources to enhance the design and practice of chronic and longevity studies involving GEM. C57BL6, 129, and FVB/N strains are emphasized because of their widespread use in the generation of knockout, transgenic, and conditional mutant GEM. Resources are included also for pathology of other inbred strain families, including A, AKR, BALB/c, C3H, C57L, C58, CBA, DBA, GR, NOD.scid, SAMP, and SJL/J, and non-inbred mice, including 4WC, AB6F1, Ames dwarf, B6, 129, B6C3F1, BALB/c,129, Het3, nude, SENCAR, and several Swiss stocks. Experimental strategies for long-term cross-sectional and longitudinal studies to assess causes of or contributors to death, disease burden, spectrum of pathology phenotypes, longevity, and functional healthy life spans (health spans) are compared and discussed.
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Affiliation(s)
- C F Brayton
- Johns Hopkins University, 733 North Broadway, BRB Ste 851, Baltimore, MD 21205, USA.
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Senoh H, Katagiri T, Takanobu K, Umeda Y, Aiso S, Fukushima S. Spontaneous harderian gland adenocarcinoma in a female f344 rat: a case report. J Toxicol Pathol 2014; 27:139-42. [PMID: 25352715 PMCID: PMC4110938 DOI: 10.1293/tox.2013-0066] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Accepted: 02/15/2014] [Indexed: 11/19/2022] Open
Abstract
Harderian gland tumors are extremely rare in female F344 rats. An expansive enlarging lesion of the Harderian gland with compression, distortion and invasion of the surrounding muscle was found in a 110-week-old female F344/DuCrj rat, which was diagnosed as a Harderian gland adenocarcinoma. Epithelial growth patterns such as glandular, lobular, papillary and duct forming patterns were exhibited in most areas of the tumor. The tumor cells were pleomorphic and atypical. In one part of the tumor, poorly differentiated areas were found. This case was observed in the middle dose group of a carcinogenicity study of diphenylamine, which was not carcinogenic, we determine to be this case was a spontaneous tumor.
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Affiliation(s)
- Hideki Senoh
- Japan Bioassay Research Center, Hadano, Kanagawa 257-0015, Japan
| | - Taku Katagiri
- Japan Bioassay Research Center, Hadano, Kanagawa 257-0015, Japan
| | - Kenji Takanobu
- Japan Bioassay Research Center, Hadano, Kanagawa 257-0015, Japan
| | - Yumi Umeda
- Japan Bioassay Research Center, Hadano, Kanagawa 257-0015, Japan
| | - Shigetoshi Aiso
- Japan Bioassay Research Center, Hadano, Kanagawa 257-0015, Japan
| | - Shoji Fukushima
- Japan Bioassay Research Center, Hadano, Kanagawa 257-0015, Japan
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McInnes EF, Scudamore CL. Review of approaches to the recording of background lesions in toxicologic pathology studies in rats. Toxicol Lett 2014; 229:134-43. [PMID: 24960062 DOI: 10.1016/j.toxlet.2014.06.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 05/30/2014] [Accepted: 06/02/2014] [Indexed: 11/15/2022]
Abstract
Pathological evaluation of lesions caused directly by xenobiotic treatment must always take into account the recognition of background (incidental) findings. Background lesions can be congenital or hereditary, histological variations, changes related to trauma or normal aging and physiologic or hormonal changes. This review focuses on the importance and correct approach to recording of background changes and includes discussion on sources of variability in background changes, the correct use of terminology, the concept of thresholds, historical control data, diagnostic drift, blind reading of slides, scoring and artifacts. The review is illustrated with background lesions in Sprague Dawley and Wistar rats.
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Affiliation(s)
- E F McInnes
- Cerberus, Unit 3, 39 Holland street, Thebarton, South Australia, 5031, Australia.
| | - C L Scudamore
- Mary Lyon Centre, MRC Harwell, Harwell Science and Innovation Campus, Oxfordshire, OX11 0RD, United Kingdom.
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Burns KM, Melnick RL. MTBE: recent carcinogenicity studies. INTERNATIONAL JOURNAL OF OCCUPATIONAL AND ENVIRONMENTAL HEALTH 2013; 18:66-9. [DOI: 10.1179/107735212x13293200778947] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
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Paranjpe MG, Denton MD, Elbekai RH. The 26-Week Tg.Rash2 Mice Carcinogenicity Studies. Toxicol Pathol 2013; 42:1153-7. [DOI: 10.1177/0192623313501726] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A typical 26-week Tg.rasH2 mouse carcinogenicity study usually has 4 dose groups, composed of 25 mice/sex, which include 1 control and 3 test article–treated groups. In every study, there is a protocol required full tissue list of 49 tissues which is examined microscopically in all animals of these 4 dose groups. Based on retrospective analysis of the historical control data collected from studies conducted in Tg.rasH2 mice from 2004 to 2012, we propose that a full tissue list be examined as usual in the control and high-dose groups; however, in the low- and mid-dose groups, only select tissues should be examined. The select tissue list is generated after analyzing common tumors, uncommon tumors seen grossly, uncommon tumors not seen grossly, organ weight variations with accountable microscopic lesions, and target organs identified in the high-dose groups. The proposed changes to the International Conference on Harmonization S1 guidance may lead to an increased need for 26-week Tg.rasH2 mice studies. The time savings resulting from processing and evaluating a select tissue list rather than a full tissue list from low- and mid-dose groups of Tg.rasH2 mouse studies will further accelerate early completion of these studies without compromising the quality and integrity.
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35
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Matsumoto M, Umeda Y, Take M, Nishizawa T, Fukushima S. Subchronic toxicity and carcinogenicity studies of 1,2-dichloropropane inhalation to mice. Inhal Toxicol 2013; 25:435-43. [DOI: 10.3109/08958378.2013.800618] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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36
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Moore NP, McFadden LG, Landenberger BD, Thomas J. Gender differences in the incidence of background and chemically induced primary pulmonary neoplasms in B6C3F1 mice: a retrospective analysis of the National Toxicology Program (NTP) carcinogenicity bioassays. ACTA ACUST UNITED AC 2013; 65:1109-15. [PMID: 23726758 DOI: 10.1016/j.etp.2013.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 05/03/2013] [Indexed: 11/28/2022]
Abstract
The National Toxicology Program (NTP) database of technical reports on carcinogenicity bioassays has been interrogated for the incidence of primary pulmonary neoplasms in B6C3F1 mice. A total of 170 study reports were selected, from studies that completed the in-life phase during 1983-2007, which included neoplasm incidence data for 180 control groups comprising both male and female mice. The incidence (median and inter-quartile range) of males with alveolar/bronchiolar adenoma was 16% (12-20%), and for females it was 5% (2-8%); the incidence of males with alveolar/bronchiolar carcinoma was 8% (4-12%), and for females it was 2% (0-4%); and the incidence of males with combined alveolar/bronchiolar adenoma or carcinoma was 24% (18-30%), and for females it was 8% (6-12%). Comparing the incidence of animals bearing these lesions on a per study basis showed the median incidence in males to be 3.0-fold, 2.0-fold, and 2.8-fold higher than in females. The incidence of other primary pulmonary neoplasms was <10% of the alveolar/bronchiolar neoplasms. Comparison of gender-specific response to lung tumorigens showed that the increase in incidence of tumors above control levels was greater in females than in males.
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Affiliation(s)
- Nigel P Moore
- Toxicology and Environmental Research and Consulting, Dow Europe GmbH, Horgen, Switzerland.
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Takaba K, Imada T, Katsumata S, Okumura H, Iwamoto S, Suzuki Y, Imaizumi M, Myojo K, Takada C, Kimoto N, Saeki K, Yamaguchi I. Spontaneous Adenosquamous Carcinoma with Rapid Growth and EMT-like Changes in the Mammary Gland of a Young Adult Female BALB/c Mouse. J Toxicol Pathol 2013; 25:265-71. [PMID: 23345929 PMCID: PMC3517922 DOI: 10.1293/tox.25.265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 01/30/2012] [Indexed: 11/19/2022] Open
Abstract
This study histopathologically and immunohistochemically investigated a spontaneously occurring single mass subcutaneously located in the left lower abdomen of a female BALB/cAJcl-nu/+ mouse at 10 weeks of age. The mass was about 20 × 15 × 10 mm in size after formalin fixation; nevertheless, it was not detected by clinical observations at 9 weeks of age. H&E staining revealed the tumor origin was epithelial and probably arose from the mammary gland, and the tumor cells demonstrated a squamous, acinar or polyhedral/basal pattern. A cell kinetics analysis revealed that many of the tumor cells of the squamous, acinar or polyhedral/basal component were positive for PCNA and cyclin D1, although there were a few of TUNEL-positive tumor cells in all of the components. An epithelial/mesenchymal analysis demonstrated that most of the tumor cells of the squamous and acinar components contained keratin and E-cadherin; however, most of the tumor cells of the polyhedral/basal component were less or very weakly positive for these markers. The tumor cells of the squamous component were negative for vimentin and SMA; however, many of the tumor cells of the polyhedral/basal component exhibited vimentin. In addition, expression of SMA was confirmed in some tumor cells of the acinar and basal components. Based on the microscopic and immunohistochemical characterizations, the tumor was diagnosed to be adenosquamous carcinoma that originated from the mammary gland with rapid growth, and the tumor cells demonstrated epithelial-mesenchymal transition-like changes.
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Affiliation(s)
- Katsumi Takaba
- Toxicological Research Laboratories, Kyowa Hakko Kirin Co., Ltd., 1188 Shimotogari, Nagaizumi-cho, Sunto-gun, Shizuoka 411-8731, Japan
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Paranjpe MG, Elbekaei RH, Shah SA, Hickman M, Wenk ML, Zahalka EA. Historical control data of spontaneous tumors in transgenic CByB6F1-Tg(HRAS)2Jic (Tg.rasH2) mice. Int J Toxicol 2013; 32:48-57. [PMID: 23324159 DOI: 10.1177/1091581812471565] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The Tg.rasH2 mouse is a hemizygous transgenic mouse, approved by regulatory agencies for carcinogenicity assessment. However, the absence of a historical database for the incidence of spontaneous neoplasms has subsequently led to reluctance by some pharmaceutical companies to adopt the use of this short-term carcinogenicity assay. Our laboratory has generated a database summarizing the mortality, body weights, and the incidence of spontaneous tumors in 1420 male and female mice assigned to 26 studies conducted at our facility. In addition, we present the incidence of tumors in positive control mice treated with urethane from these studies. Mortality in the vehicle-treated Tg.rasH2 mouse was low (average of 1% in each study). The most common spontaneous tumors in the Tg.rasH2 mice were alveolar bronchiolar adenoma of the lungs (10.14% in males and 5.77% in females) and hemangiosarcoma of the spleen (3.66% in both males and females). The incidence of all other tumors was generally very low. In the positive control, urethane-treated animals, the incidence of alveolar bronchiolar adenomas and alveolar bronchiolar carcinomas in the lungs was 93.69% and 42.88% in males and 92.43% and 72.79% in females, respectively. In addition, the incidence of splenic hemangiosarcomas in urethane-treated males was 89.18% and 92.25% in females. The 6-month Tg.rasH2 assay is more precise, faster, and more economical than the conventional 2-year mouse assays because of the low incidence of background tumors, very high survival, shorter duration, and the lower number of animals used.
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Affiliation(s)
- Madhav G Paranjpe
- BioReliance Corporation, 14920 Broschart Road Rockville, MD 20850, USA
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Rhomberg LR, Goodman JE, Prueitt RL. The Weight of Evidence Does Not Support the Listing of Styrene as "Reasonably Anticipated to be a Human Carcinogen" in NTP's Twelfth Report on Carcinogens. HUMAN AND ECOLOGICAL RISK ASSESSMENT : HERA 2013; 19:4-27. [PMID: 23335843 PMCID: PMC3545489 DOI: 10.1080/10807039.2012.650577] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2011] [Revised: 09/24/2011] [Indexed: 06/01/2023]
Abstract
Styrene was listed as "reasonably anticipated to be a human carcinogen" in the twelfth edition of the National Toxicology Program's Report on Carcinogens based on what we contend are erroneous findings of limited evidence of carcinogenicity in humans, sufficient evidence of carcinogenicity in experimental animals, and supporting mechanistic data. The epidemiology studies show no consistent increased incidence of, or mortality from, any type of cancer. In animal studies, increased incidence rates of mostly benign tumors have been observed only in certain strains of one species (mice) and at one tissue site (lung). The lack of concordance of tumor incidence and tumor type among animals (even within the same species) and humans indicates that there has been no particular cancer consistently observed among all available studies. The only plausible mechanism for styrene-induced carcinogenesis-a non-genotoxic mode of action that is specific to the mouse lung-is not relevant to humans. As a whole, the evidence does not support the characterization of styrene as "reasonably anticipated to be a human carcinogen," and styrene should not be listed in the Report on Carcinogens.
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Belsito D, Bickers D, Bruze M, Calow P, Dagli ML, Fryer AD, Greim H, Miyachi Y, Saurat JH, Sipes IG. A toxicological and dermatological assessment of aryl alkyl alcohol simple acid ester derivatives when used as fragrance ingredients. Food Chem Toxicol 2012; 50 Suppl 2:S269-313. [PMID: 22407231 DOI: 10.1016/j.fct.2012.02.091] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2011] [Revised: 02/03/2012] [Accepted: 02/27/2012] [Indexed: 11/20/2022]
Abstract
The aryl alkyl alcohol simple acid ester derivatives (AAASAE) group of fragrance ingredients was critically evaluated for safety following a complete literature search of the pertinent data. For high end users, calculated maximum skin exposures vary widely from 0.01% to 4.17%. AAASAE exhibit a common route of primary metabolism by carboxylesterases resulting in the formation of the simple acid and an aryl alkyl alcohol. They have low acute toxicity. No significant toxicity was observed in repeat-dose toxicity tests. There was no evidence of carcinogenicity of benzyl alcohol when it was administered in the feed; gavage studies resulted in pancreatic carcinogenesis due to the corn oil vehicle. The AAASAE are not mutagenic in bacterial systems or in vitro in mammalian cells, and have little to no in vivo genotoxicity. Reproductive and developmental toxicity data show no indication of adverse effects on reproductive function and NOELs for maternal and developmental toxicity are far in excess of current exposure levels. The AAASAE are generally not irritating or sensitizing at the current levels of exposure. The Panel is of the opinion that there are no safety concerns regarding the AAASAE at the current levels of use and exposure.
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Matsumoto M, Suzuki M, Kano H, Aiso S, Yamazaki K, Fukushima S. Carcinogenicity of ortho-phenylenediamine dihydrochloride in rats and mice by two-year drinking water treatment. Arch Toxicol 2012; 86:791-804. [DOI: 10.1007/s00204-012-0800-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 01/04/2012] [Indexed: 11/30/2022]
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The FEMA GRAS assessment of aliphatic and aromatic terpene hydrocarbons used as flavor ingredients. Food Chem Toxicol 2011; 49:2471-94. [DOI: 10.1016/j.fct.2011.06.011] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2010] [Revised: 05/20/2011] [Accepted: 06/01/2011] [Indexed: 01/15/2023]
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A review of mammalian carcinogenicity study design and potential effects of alternate test procedures on the safety evaluation of food ingredients. Regul Toxicol Pharmacol 2011; 60:S1-34. [DOI: 10.1016/j.yrtph.2010.10.002] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2010] [Accepted: 10/04/2010] [Indexed: 11/22/2022]
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Soffritti M, Belpoggi F, Manservigi M, Tibaldi E, Lauriola M, Falcioni L, Bua L. Aspartame administered in feed, beginning prenatally through life span, induces cancers of the liver and lung in male Swiss mice. Am J Ind Med 2010; 53:1197-206. [PMID: 20886530 DOI: 10.1002/ajim.20896] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Aspartame (APM) is a well-known intense artificial sweetener used in more than 6,000 products. Among the major users of aspartame are children and women of childbearing age. In previous lifespan experiments conducted on Sprague-Dawley rats we have shown that APM is a carcinogenic agent in multiple sites and that its effects are increased when exposure starts from prenatal life. OBJECTIVE The aim of this study is to evaluate the potential of APM to induce carcinogenic effects in mice. METHODS Six groups of 62-122 male and female Swiss mice were treated with APM in feed at doses of 32,000, 16,000, 8,000, 2,000, or 0 ppm from prenatal life (12 days of gestation) until death. At death each animal underwent complete necropsy and all tissues and organs of all animals in the experiment were microscopically examined. RESULTS APM in our experimental conditions induces in males a significant dose-related increased incidence of hepatocellular carcinomas (P < 0.01), and a significant increase at the dose levels of 32,000 ppm (P < 0.01) and 16,000 ppm (P < 0.05). Moreover, the results show a significant dose-related increased incidence of alveolar/bronchiolar carcinomas in males (P < 0.05), and a significant increase at 32,000 ppm (P < 0.05). CONCLUSIONS The results of the present study confirm that APM is a carcinogenic agent in multiple sites in rodents, and that this effect is induced in two species, rats (males and females) and mice (males). No carcinogenic effects were observed in female mice. Am. J. Ind. Med. 53:1197-1206, 2010. © 2010 Wiley-Liss, Inc.
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Affiliation(s)
- Morando Soffritti
- Cesare Maltoni Cancer Research Center, Ramazzini Institute, Bentivoglio, Bologna, Italy.
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Greim H, Hartwig A, Reuter U, Richter-Reichhelm HB, Thielmann HW. Chemically induced pheochromocytomas in rats: mechanisms and relevance for human risk assessment. Crit Rev Toxicol 2010; 39:695-718. [PMID: 19743946 DOI: 10.1080/10408440903190861] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Pheochromocytomas are tumors originating from chromaffin cells of the adrenal medulla, which have been observed in numerous carcinogenicity studies. The authors have evaluated pheochromocytoma concurrence with other effects and the possible mechanisms, in order to assess the relevance of such data for the classification of carcinogenic effects and their relevance to humans. The evaluation revealed that pheochromocytomas occur with relatively higher frequency in male rats, especially when the following conditions are involved: hypoxia, uncoupling of oxidative phosphorylation, disturbance in calcium homeostasis, and disturbance of the hypothalamic endocrine axis. The underlying biochemical mechanisms suggest that other substances that interfere with these biochemical endpoints also produce pheochromocytomas. Such endpoints include enzymes involved in catecholamine synthesis, receptor tyrosine kinase (RET), hypoxia-inducible factor (HIF), succinate dehydrogenase, fumarate hydratase, and pyruvate dehydrogenase. To date, there is no indication that the substances inducing pheochromocytomas in animal experiments also induce corresponding tumors in humans. Because the mechanisms of action identified in rats are to be expected in humans, pheochromocytomas may be induced after exposure conditions similar to those used in the animal studies. Whether hereditary mutations represent a risk factor in humans is not clear. Pheochromocytomas that occur in animal experiments currently appear to have little relevance for conditions at the work place. When sufficiently documented and evaluated, such secondary pheochromocytomas are not relevant for classification and human risk assessment.
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Affiliation(s)
- Helmut Greim
- Institute of Toxicology and Environmental Hygiene, Technical University of Munich, Freising-Weihenstephan, Berlin, Germany.
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Cruzan G, Bus J, Banton M, Gingell R, Carlson G. Mouse specific lung tumors from CYP2F2-mediated cytotoxic metabolism: An endpoint/toxic response where data from multiple chemicals converge to support a mode of action. Regul Toxicol Pharmacol 2009; 55:205-18. [DOI: 10.1016/j.yrtph.2009.07.002] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2009] [Revised: 07/01/2009] [Accepted: 07/02/2009] [Indexed: 11/28/2022]
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Keenan C, Elmore S, Francke-Carroll S, Kemp R, Kerlin R, Peddada S, Pletcher J, Rinke M, Schmidt SP, Taylor I, Wolf DC. Best practices for use of historical control data of proliferative rodent lesions. Toxicol Pathol 2009; 37:679-93. [PMID: 19454599 DOI: 10.1177/0192623309336154] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Maronpot RR. Biological Basis of Differential Susceptibility to Hepatocarcinogenesis among Mouse Strains. J Toxicol Pathol 2009; 22:11-33. [PMID: 22271974 PMCID: PMC3246016 DOI: 10.1293/tox.22.11] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2008] [Accepted: 11/07/2008] [Indexed: 12/13/2022] Open
Abstract
There is a vast amount of literature related to mouse liver tumorigenesis generated over the past 60 years, not all of which has been captured here. The studies reported in this literature have generally been state of the art at the time they were carried out. A PubMed search on the topic "mouse liver tumors" covering the past 10 years yields over 7000 scientific papers. This review address several important topics related to the unresolved controversy regarding the relevance of mouse liver tumor responses observed in cancer bioassays. The inherent mouse strain differential sensitivities to hepatocarcinogenesis largely parallel the strain susceptibility to chemically induced liver neoplasia. The effects of phenobarbital and halogenated hydrocarbons in mouse hepatocarcinogenesis have been summarized because of recurring interest and numerous publications on these topics. No single simple paradigm fully explains differential mouse strain responses, which can vary more than 50-fold among inbred strains. In addition to inherent genetics, modifying factors including cell cycle balance, enzyme induction, DNA methylation, oncogenes and suppressor genes, diet, and intercellular communication influence susceptibility to spontaneous and induced mouse hepatocarcinogenesis. Comments are offered on the evaluation, interpretation, and relevance of mouse liver tumor responses in the context of cancer bioassays.
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Affiliation(s)
- Robert R Maronpot
- Maronpot Consulting, LLC, 1612 Medfield Road, Raleigh, NC 27607-4726, USA
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Holder JW. Analysis of chloroethane toxicity and carcinogenicity including a comparison with bromoethane. Toxicol Ind Health 2008; 24:655-75. [DOI: 10.1177/0748233708100371] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Chloroethane (CE) gas carcinogenicity is analyzed and determined from a National Toxicology Program (NTP) bioassay where an inhalation concentration of 15,000 ppm CE gas in air produced the highest incidence of an uncommon-to-rare tumor ever observed by the NTP. Persistently inhaled CE produces endometrial cancers in female mice. The first-tumor-corrected uterine endometrial incidence (I) in B6C3F1 mice is 90%, but no significant tumors occurred in F344 rats. The endometrial cancers dispersed by 1) migrating locally to the adjacent myometrium, 2) then migrating to the bloodstream by intravasation, 3) entering 17 distal organs by extravasation and adapting to the new tissue environment. Distal cancers retained sufficient endometrial cell features to be recognized at each metastatic site. CE produced one of the highest metastasis rates ever observed by NTP of 79%. Comparing CE with bromoethane (BE), a structural analogue, it was found that BE too produced rare murine endometrial cancers yielding the second highest NTP incidence rate of I = 58% with a similar high malignancy rate of 56%. Because of the historical rarity of endometrial tumors in the B6C3F1 mouse, both of these SAR haloethanes seem to be evoking a strong, related carcinogenic potential in B6C3F1 mice, but not in F344 rats. The question of whether humans are similar to mice or to rats is addressed here and in Gargas, et al., 2008. The powerful carcinogenesis caused by these halohydrocarbons may have been caused by excessive and metabolically unresolved acetaldehyde (AC) which is directly generated by Cyp2E1 in the oxidative elimination of CE. With >95% AC metabolic production, as predicted from pharmacokinetic (PK) studies depending on CE exposure, AC is the main elimination intermediate. AC is a known animal carcinogen and a strongly suspected human carcinogen. Also, CE causes incipient decreases of tissue essential glutathione pools [GSH] by Phase II conjugation metabolic elimination of CE (and BE), by glutantione transferase (GST), in most organs (except brain) exposed to high circulating CE and it metabolites. In three laboratories, an excessive stress reaction of hyperkinesis was observed only during 15,000 ppm gas exposure but not when the exposure ceased or when exposure was presented at 150 ppm. Test rodents other than the female mice did not exhibit a pattern of visible stress nor did they have a carcinogenic response to CE gas. Unremitting stress has been documented to contribute a feedback to the hypothalamus which stimulates the hypothalamic-pituitary-axis (HPA), which in turn, induces the adrenal glands. Because estrus and estrogen and progesterone levels were unaltered by CE gas, the adrenal over stimulation, causing high steroid output, may be the penultimate step in this extraordinary carcinogenic response. High adrenal production of corticosteroids could adversely promote endometrial cells to cancers in mice − a mechanism that has already been observed in humans.
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Affiliation(s)
- JW Holder
- National Center for Environmental Assessment, Office of Research and Development, US Environmental Protection Agency, Washington, District of Columbia, USA
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