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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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2
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He Y, Kim IK, Bian J, Polyzos A, Di Giammartino DC, Zhang YW, Luo J, Hernandez MO, Kedei N, Cam M, Borczuk AC, Lee T, Han Y, Conner EA, Wong M, Tillo DC, Umemura S, Chen V, Ruan L, White JB, Miranda IC, Awasthi PP, Altorki NK, Divakar P, Elemento O, Apostolou E, Giaccone G. A Knock-In Mouse Model of Thymoma With the GTF2I L424H Mutation. J Thorac Oncol 2022; 17:1375-1386. [PMID: 36049655 PMCID: PMC9691559 DOI: 10.1016/j.jtho.2022.08.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Accepted: 08/02/2022] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The pathogenesis of thymic epithelial tumors remains largely unknown. We previously identified GTF2I L424H as the most frequently recurrent mutation in thymic epithelial tumors. Nevertheless, the precise role of this mutation in tumorigenesis of thymic epithelial cells is unclear. METHODS To investigate the role of GTF2I L424H mutation in thymic epithelial cells in vivo, we generated and characterized a mouse model in which the Gtf2i L424H mutation was conditionally knocked-in in the Foxn1+ thymic epithelial cells. Digital spatial profiling was performed on thymomas and normal thymic tissues with GeoMx-mouse whole transcriptome atlas. Immunohistochemistry staining was performed using both mouse tissues and human thymic epithelial tumors. RESULTS We observed that the Gtf2i mutation impairs development of the thymic medulla and maturation of medullary thymic epithelial cells in young mice and causes tumor formation in the thymus of aged mice. Cell cycle-related pathways, such as E2F targets and MYC targets, are enriched in the tumor epithelial cells. Results of gene set variation assay analysis revealed that gene signatures of cortical thymic epithelial cells and thymic epithelial progenitor cells are also enriched in the thymomas of the knock-in mice, which mirrors the human counterparts in The Cancer Genome Atlas database. Immunohistochemistry results revealed similar expression pattern of epithelial cell markers between mouse and human thymomas. CONCLUSIONS We have developed and characterized a novel thymoma mouse model. This study improves knowledge of the molecular drivers in thymic epithelial cells and provides a tool for further study of the biology of thymic epithelial tumors and for development of novel therapies.
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Affiliation(s)
- Yongfeng He
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, New York
| | - In-Kyu Kim
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia
| | - Jing Bian
- CCR Collaborative Bioinformatics Resource, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Alexander Polyzos
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, New York
| | | | - Yu-Wen Zhang
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia; New address: Department of Cell Biology, University of Virginia, School of Medicine, Charlottesville, Virginia
| | - Ji Luo
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland
| | - Maria O Hernandez
- Collaborative Protein Technology Resource, Office of Science and Technology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Noemi Kedei
- Collaborative Protein Technology Resource, Office of Science and Technology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Maggie Cam
- CCR Collaborative Bioinformatics Resource, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Alain C Borczuk
- Department of Pathology, Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, New York; New address: Department of Pathology, Northwell Health, Greenvale, New York
| | - Trevor Lee
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, New York
| | - Yumin Han
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, New York
| | | | - Madeline Wong
- CCR Genomics Core, National Cancer Institute, Bethesda, Maryland
| | - Desiree C Tillo
- CCR Genomics Core, National Cancer Institute, Bethesda, Maryland
| | - Shigeki Umemura
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia
| | - Vincent Chen
- Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia
| | - Lydia Ruan
- CCR Collaborative Bioinformatics Resource, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Jessica B White
- Caryl and Israel Englander Institute for Precision Medicine, New York-Presbyterian Hospital, Weill Cornell Medicine, New York, New York
| | - Ileana C Miranda
- Laboratory of Comparative Pathology, Memorial Sloan Kettering Cancer Center, Weill Cornell Medicine, and The Rockefeller University, New York, New York
| | - Parirokh P Awasthi
- Frederick National Laboratory for Cancer Research, Laboratory Animal Sciences, Mouse Modeling & Cryopreservation, National Cancer Institute, Frederick, Maryland
| | - Nasser K Altorki
- Department of Cardiothoracic Surgery, Weill Cornell Medicine, New York Presbyterian Hospital, New York, New York
| | | | - Olivier Elemento
- Caryl and Israel Englander Institute for Precision Medicine, New York-Presbyterian Hospital, Weill Cornell Medicine, New York, New York
| | - Effie Apostolou
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, New York
| | - Giuseppe Giaccone
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, New York; Department of Oncology, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia.
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3
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Okumura N, Kondo H, Suzuki S, Shibuya H. Thymoma originating from the cervical component of the thymus in a degu. J Vet Diagn Invest 2021; 34:126-129. [PMID: 34515595 DOI: 10.1177/10406387211045643] [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: 11/15/2022] Open
Abstract
A 5-y-old, male degu (Octodon degus) was presented with a subcutaneous mass in the ventral aspect of the cervical area. The mass was removed surgically. Histologically, the mass was a densely cellular, expansile neoplasm, with compression of thymic tissue to the periphery. The neoplasm consisted of solid sheets of polygonal cells, mixed with fewer small lymphocytes. Rare Hassall bodies were scattered throughout the mass. Polygonal cells were positive for anti-keratin/cytokeratin AE1/AE3 antibody, and small lymphocytes were positive for anti-CD3 antibody. The histopathologic and immunohistochemical findings were consistent with a thymoma. In addition, an autopsy revealed myxosarcoma of the right thoracic wall with metastasis to the lung. To our knowledge, thymoma originating from the cervical component of the thymus has not been documented previously in a rodent species.
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Affiliation(s)
- Naka Okumura
- Laboratory of Veterinary Pathology, Department of Veterinary Medicine, Nihon University, Fujisawa, Kanagawa, Japan
| | - Hirotaka Kondo
- Laboratory of Veterinary Pathology, Department of Veterinary Medicine, Nihon University, Fujisawa, Kanagawa, Japan
| | | | - Hisashi Shibuya
- Laboratory of Veterinary Pathology, Department of Veterinary Medicine, Nihon University, Fujisawa, Kanagawa, Japan
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Tomonari Y, Sato J, Yamada N, Kurotaki T, Doi T, Kanno T, Tsuchitani M. Immunohistochemical Characteristics of Thymomas and Hyperplastic Lesions in Wistar Hannover Rats. Toxicol Pathol 2020; 48:649-655. [PMID: 32508247 DOI: 10.1177/0192623320922849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Previously, we investigated the higher incidence of hyperplastic lesions and thymomas and histopathological resemblance of cortex-medullary structures between thymomas and normal thymuses in Wistar Hannover (WH) rats. Thymomas had pale-staining cell foci (PA) similar to medulla but without lymphocytes. Here, we focused on the differences in cytokeratin (CK) expression in the thymic epithelia of the cortex and medulla and compared the structures of thymomas and normal thymuses. Thymomas, hyperplastic lesions, and normal thymuses obtained from background studies of WH rats were stained with antibodies against CK14, CK18, and CD20. In normal thymuses, the epithelial cells were positive for CK14 in the medulla and subcapsular area and for CK18 in the cortex, B-cells were positive for CD20 in the medulla. In thymomas, the epithelial cells were positive for CK14 in the medullary differentiation (MD) areas and for CK18 in the cortex-like lymphocyte rich and PA, and B-cells were positive for CD20 in the MD areas.
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Affiliation(s)
- Yuki Tomonari
- Pathology Department, Nonclinical Research Center, LSI Medience Corporation, Kamisu-shi, Ibaraki, Japan
| | - Junko Sato
- Pathology Department, Nonclinical Research Center, LSI Medience Corporation, Kamisu-shi, Ibaraki, Japan
| | - Naoaki Yamada
- Pathology Department, Nonclinical Research Center, LSI Medience Corporation, Kamisu-shi, Ibaraki, Japan
| | - Tetsuro Kurotaki
- Pathology Department, Nonclinical Research Center, LSI Medience Corporation, Kamisu-shi, Ibaraki, Japan
| | - Takuya Doi
- Pathology Department, Nonclinical Research Center, LSI Medience Corporation, Kamisu-shi, Ibaraki, Japan
| | - Takeshi Kanno
- Pathology Department, Nonclinical Research Center, LSI Medience Corporation, Kamisu-shi, Ibaraki, Japan
| | - Minoru Tsuchitani
- Pathology Department, Nonclinical Research Center, LSI Medience Corporation, Kamisu-shi, Ibaraki, Japan
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Willard-Mack CL, Elmore SA, Hall WC, Harleman J, Kuper CF, Losco P, Rehg JE, Rühl-Fehlert C, Ward JM, Weinstock D, Bradley A, Hosokawa S, Pearse G, Mahler BW, Herbert RA, Keenan CM. Nonproliferative and Proliferative Lesions of the Rat and Mouse Hematolymphoid System. Toxicol Pathol 2020; 47:665-783. [PMID: 31526133 DOI: 10.1177/0192623319867053] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The INHAND Project (International Harmonization of Nomenclature and Diagnostic Criteria for Lesions in Rats and Mice) is a joint initiative of the Societies of Toxicologic Pathology from Europe (ESTP), Great Britain (BSTP), Japan (JSTP), and North America (STP) to develop an internationally accepted nomenclature for proliferative and nonproliferative changes in rats and mice. The purpose of this publication is to provide a standardized nomenclature for classifying changes observed in the hematolymphoid organs, including the bone marrow, thymus, spleen, lymph nodes, mucosa-associated lymphoid tissues, and other lymphoid tissues (serosa-associated lymphoid clusters and tertiary lymphoid structures) with color photomicrographs illustrating examples of the lesions. Sources of material included histopathology databases from government, academia, and industrial laboratories throughout the world. Content includes spontaneous lesions as well as lesions induced by exposure to test materials. The nomenclature for these organs is divided into 3 terminologies: descriptive, conventional, and enhanced. Three terms are listed for each diagnosis. The rationale for this approach and guidance for its application to toxicologic pathology are described in detail below.
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Affiliation(s)
| | - Susan A Elmore
- Thymus subgroup lead.,National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | | | - Johannes Harleman
- Lymph node subgroup lead.,Neoplasm subgroup leads.,Independent Consultant, Darmstadt, Germany
| | - C Frieke Kuper
- Associated lymphoid organs subgroup lead.,Independent Consultant, Utrecht, the Netherlands
| | - Patricia Losco
- General hematolymphoid subgroup lead.,Independent Consultant, West Chester, PA, USA
| | - Jerold E Rehg
- Spleen subgroup leads.,Neoplasm subgroup leads.,Saint Jude Children's Research Hospital, Memphis, TN, USA
| | | | - Jerrold M Ward
- Spleen subgroup leads.,Neoplasm subgroup leads.,Global VetPathology, Montgomery Village, MD, USA
| | | | - Alys Bradley
- Charles River Laboratories, Tranent, Scotland, United Kingdom
| | - Satoru Hosokawa
- Eisai Co, Ltd, Drug Safety Research Laboratories, Ibaraki, Japan
| | | | - Beth W Mahler
- Experimental Pathology Laboratories, Research Triangle Park, NC, USA
| | - Ronald A Herbert
- National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
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Hojo M, Sakamoto Y, Maeno A, Tayama K, Tada Y, Yuzawa K, Ando H, Kubo Y, Nagasawa A, Tanaka K, Yano N, Kaihoko F, Hasegawa Y, Suzuki T, Inomata A, Moriyasu T, Miyajima K, Nakae D. A histopathological analysis of spontaneous neoplastic and non-neoplastic lesions in aged male RccHan:WIST rats. J Toxicol Pathol 2019; 33:47-55. [PMID: 32051666 PMCID: PMC7008206 DOI: 10.1293/tox.2019-0064] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 10/21/2019] [Indexed: 12/28/2022] Open
Abstract
Histopathological information about spontaneous lesions in aged Hannover Wistar rats is limited. In this study, we describe spontaneous lesions found in 39 male RccHan:WIST rats used as a control in a carcinogenicity study. Neoplastic lesions were frequently seen in the endocrine system, such as pituitary adenomas in the pars distalis. This strain exhibited a high incidence of thymoma (10.3%), compared to other strains. We encountered an oligodendroglioma, a pituitary adenoma of the pars intermedia, and a prostate adenocarcinoma, which are comparatively rare in rats. While the variety and incidence of non-neoplastic lesions were similar to those in other strains, several interesting lesions occurred with relatively high incidence, including "harderianization" of the extraorbital lacrimal gland, common bile duct ectasia, and hyperplasia of pulmonary endocrine cells in the lung. Furthermore, comparative analyses demonstrated that the severity of chronic progressive nephropathy and murine progressive cardiomyopathy in RccHan:WIST rats was less than that in F344 rats.
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Affiliation(s)
- Motoki Hojo
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Yoshimitsu Sakamoto
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Ai Maeno
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Kuniaki Tayama
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Yukie Tada
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Katsuhiro Yuzawa
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Hiroshi Ando
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Yoshikazu Kubo
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Akemichi Nagasawa
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Kazuyoshi Tanaka
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Norio Yano
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Fujifumi Kaihoko
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Yuko Hasegawa
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Toshinari Suzuki
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Akiko Inomata
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Takako Moriyasu
- Department of Pharmaceutical and Environmental Sciences, Tokyo Metropolitan Institute of Public Health, 3-24-1 Hyakunincho, Shinjuku, Tokyo 169-0073, Japan
| | - Katsuhiro Miyajima
- Department of Nutritional Science and Food Safety, Faculty of Applied Biosciences, Tokyo University of Agriculture, 1-1-1 Sakura-ga-Oka, Setagaya, Tokyo 156-8502, Japan
| | - Dai Nakae
- Department of Nutritional Science and Food Safety, Faculty of Applied Biosciences, Tokyo University of Agriculture, 1-1-1 Sakura-ga-Oka, Setagaya, Tokyo 156-8502, Japan
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Moore RR, Nagai H, Miller RA, Hardisty JF, Allison N, Shockley KR, Malarkey DE. Comparative Incidences and Biological Outcomes for Thymoma in Various Rat Strains in National Toxicology Program Studies. Toxicol Pathol 2019; 47:833-841. [PMID: 31394971 PMCID: PMC6814546 DOI: 10.1177/0192623319863119] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Thymomas from 277 Fischer 344/N (F344/N), 10 Sprague Dawley (HSD:Sprague Dawley SD) (SD), 129 Wistar Han [Crl:WI(Han)] (WH), and 4 Wistar Outbred (WO) rats were reviewed from long-term studies in the National Toxicology Program (NTP) database. The incidence of thymomas in F344/N rats was slightly higher in males than in females, while the incidences in SD and WH rats were higher in females than in males. Only male WO rats were used in NTP studies. Of the 277 thymomas in F344/N rats, 235 (84.8%) were benign and 42 (15.2%) malignant, 14 of which exhibited metastasis. Of the 10 thymomas in SD rats, 5 (50%) were benign and 5 (50%) were malignant, one of which exhibited metastasis. Of the 129 thymomas in WH rats, 126 (98%) were benign and 3 (2%) were malignant, 1 with metastasis. Of the 4 thymomas in WO rats, 3 (75%) were benign and 1 (25%) was malignant, with no metastases. Malignant thymomas in F344/N and WH rats showed a propensity to be the cause of death and to result in early mortality, whereas the benign thymomas were associated less often with decreased survival. No occurrences of this neoplasm were reported to be related to exposure to any test articles.
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Affiliation(s)
- Rebecca R Moore
- Integrated Laboratory Systems, Inc, Research Triangle Park, NC, USA
| | - Hiroaki Nagai
- Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Rodney A Miller
- Experimental Pathology Laboratories, Inc, Research Triangle Park, NC, USA
| | - Jerry F Hardisty
- Experimental Pathology Laboratories, Inc, Research Triangle Park, NC, USA
| | - Neil Allison
- Experimental Pathology Laboratories, Inc, Research Triangle Park, NC, USA
| | - Keith R Shockley
- Biostatistics and Computational Biology Branch, Division of Intramural Research, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - David E Malarkey
- Cellular and Molecular Pathology Branch, Division of the National Toxicology Program, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
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