Superfund Research Program
Distinguished Lecture Highlights Mechanisms of Liver Cancer
In a May 15 seminar at NIEHS, Michael Karin, Ph.D., detailed the sequence of molecular changes in the liver that eventually lead to liver cancer. Karin, a Distinguished Professor of Pharmacology and Pathology at the University of California, San Diego (UCSD) School of Medicine, is part of the UCSD Superfund Research Program (SRP) Center.
SRP Director Bill Suk, Ph.D., hosted the talk. In his introduction, Suk explained that Karin has studied the relationship between inflammation, cancer, and metabolic disease at UCSD since 1986.
The Karin group is interested in nonalcoholic steatohepatitis (NASH), one of the more serious illnesses in a group of metabolic disorders known as nonalcoholic fatty liver disease (NAFLD). NAFLD, which affects one-third of U.S. adults, starts as simple fatty liver, but 10–15 percent of patients will develop NASH.
"The factors that control the switch from simple fatty liver to NASH are not clear," Karin said, "but we speculate that it is associated with stress in a part of the cell called the endoplasmic reticulum (ER)."
The ER is a network of tubules in plant and animal cells that produce lipid and proteins. Karin and his colleagues decided to test the hypothesis that the ER was involved using mice that are more likely to develop ER stress in the liver.
In these mice, Karin and his colleagues revealed that a high-fat diet increases ER stress, which activates proteins that increase the production of cholesterol and fatty acids. This process gives rise to cell death and inflammation and, ultimately, the progression from simple fatty liver to NASH.
"Not only does Karin’s work in mice provide a new model for understanding the development of NASH, but it may also uncover what happens in the steps from NASH to liver cancer," said Suk.
Public Webinar Outlines Latest PFAS Exposure and Health Research
New information on per- and polyfluoroalkyl substances (PFAS) in drinking water and potential health effects was the focus of a May 1 Collaborative on Health and the Environment (CHE) webinar. The webinar was co-organized by the Boston University (BU) Superfund Research Program (SRP) Center.
PFAS chemicals have received increasing attention because they have been found in several drinking water systems and have been linked to reproductive, developmental, liver, kidney, and immunological effects.
In a December 2016 CHE call, presenters outlined the problem of PFAS in drinking water. Because of continued interest in the topic and the high volume of emerging research, organizers held this follow-up webinar to delve into practical information about PFAS testing and interpretation of contamination data, as well as new findings on potential health effects. Speakers included BU SRP Center grantee Tom Webster, D.Sc.; Nancy Rothman, Ph.D., CEO and Principal Scientist of New Environmental Horizon, Inc.; and Richard Spiese, of the Vermont Department of Environmental Conservation, Waste Management Division.
Talks by Rothman and Spiese focused on the latest methods for measuring PFAS in drinking water and how PFAS contamination in drinking water is being addressed.
"The field of expertise is expanding quickly, and there are a lot of resources to help you keep informed on changes to regulations and methods for testing," said Rothman. She emphasized the importance of using labs with experience in PFAS analysis and described the data needed to accurately measure PFAS in community drinking water.
Spiese described lessons learned on installing and operating systems to remove PFAS at impacted residences in Vermont. He discussed system installation and their process for inspection, maintenance, and long-term monitoring of PFAS concentrations.
Webster followed the first two talks with the current state of the science on the health effects of PFAS exposure.
"We have seen an explosion of research on PFAS since the last call in December 2016," Webster said. "Since then, about 40 PFAS epidemiology papers have been published linking PFAS to health outcomes." These studies have reported associations between increased PFAS exposure and higher risk of preterm birth, thyroid hormone disruption, and decreased visual motor ability.
The webinar was moderated by BU SRP Research Translation Core leader Wendy Heiger-Bernays, Ph.D. In her introduction, she provided a short overview of the SRP and encouraged participants to learn more about the University of Rhode Island SRP Center, which is focused on sources, transport, exposure, and effects of PFAS.
EPA Adds Six Hazardous Waste Sites to the National Priorities List
The U.S. Environmental Protection Agency (EPA) recently announced that it added six hazardous waste sites to the National Priorities List (NPL) of Superfund sites. In addition, EPA is proposing to add four additional sites to the list.
The added sites in Delaware, Indiana, Minnesota, South Carolina, and Texas include former textile manufacturing sites, former metal finishing and electroplating sites, and groundwater plumes.
Superfund is the federal program that investigates and cleans up complex, uncontrolled, or abandoned hazardous waste sites in the country. Proposed and newly added NPL sites may offer opportunities for SRP grantees to conduct research.