Session II - Identifying Hallmarks and Key Characteristics
Thursday, May 28, 2:00 – 4:00 p.m. EDT
Session II Registration
The NIEHS Superfund Research Program (SRP) is hosting a Risk e-Learning webinar series focused on understanding the health effects of exposures when there is a lag between exposure and the onset of the disease. In the second session, presenters will discuss new methods to better understand potential disease risk by identifying key characteristics or hallmarks of chemicals and disease. This research may provide insight into identifying chemicals that may lead to disease earlier on in the disease progression and help explore how aging itself can be a risk factor for disease. Martyn Smith, Ph.D.,
director of the University of California, Berkeley SRP Center, will describe the key characteristics approach to helping identify chemicals that cause cancer and other adverse outcomes. In evaluating whether a chemical can cause cancer or another adverse outcome, three lines of evidence are typically considered: epidemiology, animal bioassays, and mechanistic evidence. The key characteristics (KC) form the basis of a uniform approach for searching, organizing, and evaluating mechanistic evidence to support hazard identification without the need for a deductive hypothesis. KCs are the established properties of the chemicals and have been developed for carcinogens, endocrine disruptors, reproductive and neuro-toxicants, and are becoming increasingly used by authoritative bodies and regulatory agencies. Michelle La Merrill, Ph.D.,
associate professor at the University of California, Davis, will focus on using the key characteristics of endocrine disruptors to organize mechanistic support of the developmental basis of endocrine disruption. Endocrine-disrupting chemicals (EDCs) are exogenous chemicals that interfere with hormone action, thereby increasing health risks, such as for cancer, reproductive impairment, cognitive deficits, and obesity. Inspired by work to improve hazard identification of carcinogens using KCs, they have developed 10 KCs of EDCs based on our knowledge of hormone actions and EDC effects. This presentation will reveal how these 10 KCs can be used to identify, organize and utilize mechanistic data when evaluating chemicals as EDCs that contribute to developmental vulnerability to adult disease, and use DDT and bisphenol A as examples to illustrate this approach. Ron Kohanski, Ph.D.,
deputy director of the Division of Aging Biology at the National Institute on Aging, will focus on aging as a risk factor for disease. Geroscience is a recently evolved field of research on the intersection between the biology of aging and the biology of disease. The geroscience hypothesis states that "slowing the rate of aging will delay the onset and decrease the severity of chronic diseases and comorbidities that primarily impact older people." This does not mean that old age per se is a risk factor, any more than claiming that childhood is a risk factor for diseases that primarily afflict children. However, in the latter case the underlying causes may be the stage of development does not yet confer resilience against pathogens, for example. In the former case, the underlying causes may be loss of that resilience (acquired over a lifetime) from the failure of underlying molecular networks that maintain the body and adapt to environmental changes. This talk will present a viewpoint that aging can be treated as a risk factor, attempting to show that both the magnitude and duration of changes that are the process of aging can be altered in ways that are either beneficial or detrimental to health.