Molecular Pathogenesis Group | National Institute of Environmental Health Sciences
Skip Navigation
Molecular Pathogenesis Group
Close the left navigation
Add
Much of the work carried out by DTT is in support of the National Toxicology Program (NTP), an interagency partnership of the Food and Drug Administration, National Institute for Occupational Safety and Health, and NIEHS.
Visit the NTP Website
Mechanistic Toxicology Branch
Darlene Dixon, D.V.M., Ph.D., D.A.C.V.P.
Acting Chief, Mechanistic Toxicology Branch
Tel 984-287-3848
[email protected]
Research Summary
The Molecular Pathogenesis Group has focused on defining the pathogenesis/carcinogenesis of tumors affecting the reproductive tract of rodents and humans, and assessing the role of environmental and endogenous hormonal factors in the growth of these tumors.
The group has used cell lines, archival mouse tissue and human clinical samples to investigate the influence of growth factors/receptors and their signaling pathways on uterine leiomyoma (fibroid) growth. The clinical tissues used are leiomyoma and patient-matched myometrial samples taken from cycle-staged, premenopausal women that are part of the NIEHS/George Washington University Fibroid Study. The rodent tissue samples are from either in-house studies or the archives of the NTP.
By understanding the basic mechanisms of disease, therapeutic interventions can be developed that will help spawn alternative non-invasive treatments for clinical fibroids and other diseases.
Major areas of research:
Determination of the role of growth factors/receptors and their signaling pathways in regulating uterine fibroid growth
Investigation of the effects of endogenous and environmental hormones on uterine fibroid growth
Characterization of in vitro and animal models for studying the pathogenesis of uterine fibroids
Current projects:
Animal models of human disease
Effects of bromoethane in the uterus of ovariectomized B6C3F1 mice
Induction of telomerase activity in human uterine leiomyoma cell lines
Role of growth factors in the pathogenesis of uterine leiomyoma growth in women
Darlene Dixon, D.V.M., Ph.D., leads the Molecular Pathogenesis Group within the NTP Laboratory. She earned her Doctor of Veterinary Medicine (D.V.M.) degree in 1982 at Tuskegee University School of Veterinary Medicine and her Ph.D. in 1985 at Michigan State University. She served as a Postdoctoral Fellow at The Rockefeller University before joining NIEHS in 1987. She is a Diplomate in the American College of Veterinary Pathologists (ACVP board certified in 1987).
Recent Publications
Lunn R, Helmick K, Cooney G, Clemons M, Polansky M, Snow S, Tracy W, Dixon D. CVD Environmental Health Disparities Tool: systematic evidence mapping of psychosocial stressors, environmental exposures, and cardiovascular diseases to inform disparities research and action.
Environmental health : a global access science source
2026 Feb 26;25(1):.
Abstract
Lunn R, Helmick K, Cooney G, Clemons M, Polansky M, Snow S, Tracy W, Dixon D. CVD Environmental Health Disparities Tool: systematic evidence mapping of psychosocial stressors, environmental exposures, and cardiovascular diseases to inform disparities research and action. Environmental health : a global access science source. 2026 Feb 26
Ooka M, Zhao J, Zhang L, Huang R, Sakamuru S, TeKrony C, Hsieh J, Collins B, Dunnick J, Dixon D, Xia M. Profiling of Environmental Mixtures Containing Metals for Their Toxicity Pathways and Mechanism of Action.
Environmental science & technology
2025 Mar 18;59(10):4778-4787.
Abstract
Ooka M, Zhao J, Zhang L, Huang R, Sakamuru S, TeKrony C, Hsieh J, Collins B, Dunnick J, Dixon D, Xia M. Profiling of Environmental Mixtures Containing Metals for Their Toxicity Pathways and Mechanism of Action. Environmental science & technology. 2025 Mar 18
Wu X, Kreutz A, Dixon D, Tokar E. Engineering human cerebral organoids to explore mechanisms of arsenic-induced developmental neurotoxicity.
Toxicology and applied pharmacology
2025 Mar;496:117230.
Abstract
Wu X, Kreutz A, Dixon D, Tokar E. Engineering human cerebral organoids to explore mechanisms of arsenic-induced developmental neurotoxicity. Toxicology and applied pharmacology. 2025 Mar
Smarr M, Rappazzo K, Dixon D. Editorial: Environmental impacts on women's health disparities and reproductive health: advancing environmental health equity in clinical and public health practice.
Frontiers in reproductive health
2024;6:1484406.
Abstract
Smarr M, Rappazzo K, Dixon D. Editorial: Environmental impacts on women's health disparities and reproductive health: advancing environmental health equity in clinical and public health practice. Frontiers in reproductive health. 2024
Liu J, Yu L, Castro L, Yan Y, Bushel P, Scappini E, Dixon D. Induction of fibrosis following exposure to bisphenol A and its analogues in 3D human uterine leiomyoma cultures.
Journal of hazardous materials
2024 Sep 05;476:134772.
Abstract
Liu J, Yu L, Castro L, Yan Y, Bushel P, Scappini E, Dixon D. Induction of fibrosis following exposure to bisphenol A and its analogues in 3D human uterine leiomyoma cultures. Journal of hazardous materials. 2024 Sep 05
NTP Reports
CLARITY-BPA Research Program. NTP Research Report on the Consortium Linking Academic and Regulatory Insights on Bisphenol A Toxicity (CLARITY-BPA): A Compendium of Published Findings: Research Report 18
NTP Research Reports
2021 Oct [Epub ahead of print].
Abstract
CLARITY-BPA Research Program. NTP Research Report on the Consortium Linking Academic and Regulatory Insights on Bisphenol A Toxicity (CLARITY-BPA): A Compendium of Published Findings: Research Report 18 NTP Research Reports. 2021 Oct
More Recent Publications from PubMed
Related Links
Dixon, Germolec, King-Herbert step into leadership of global scientific organizations
- Environmental Factor, March 2021
Back
to Top
Last Reviewed: March 18, 2026