Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Cancer biologists find DNA-damaging toxins in common plant-based foods

Liquid smoke, black and green teas and coffee produced levels of cell DNA damage comparable to chemo drugs

In a laboratory study pairing food chemistry and cancer biology, scientists at the Johns Hopkins Kimmel Cancer Center tested the potentially harmful effect of foods and flavorings on the DNA of cells. They found that liquid smoke flavoring, black and green teas and coffee activated the highest levels of a well-known, cancer-linked gene called p53.

The p53 gene becomes activated when DNA is damaged. Its gene product makes repair proteins that mend DNA. The higher the level of DNA damage, the more p53 becomes activated.

"We don't know much about the foods we eat and how they affect cells in our bodies," says Scott Kern, M.D., the Kovler Professor of Oncology and Pathology at the Johns Hopkins University School of Medicine. "But it's clear that plants contain many compounds that are meant to deter humans and animals from eating them, like cellulose in stems and bitter-tasting tannins in leaves and beans we use to make teas and coffees, and their impact needs to be assessed."

Kern cautioned that his studies do not suggest people should stop using tea, coffee or flavorings, but do suggest the need for further research.

The Johns Hopkins study began a year ago when graduate student Samuel Gilbert, working in Kern's laboratory, noted that a test Kern had developed to detect p53 activity had never been used to identify DNA-damaging substances in food.

For the study, published online February 8 in Food and Chemical Toxicology, Kern and his team sought advice from scientists at the U.S. Department of Agriculture about food products and flavorings. "To do this study well, we had to think like food chemists to extract chemicals from food and dilute food products to levels that occur in a normal diet," he says.

Using Kern's test for p53 activity, which makes a fluorescent compound that "glows" when p53 is activated, the scientists mixed dilutions of the food products and flavorings with human cells and grew them in laboratory dishes for 18 hours.

Measuring and comparing p53 activity with baseline levels, the scientists found that liquid smoke flavoring, black and green teas and coffee showed up to nearly 30-fold increases in p53 activity, which was on par with their tests of p53 activity caused by a chemotherapy drug called etoposide.

Previous studies have shown that liquid smoke flavoring damages DNA in animal models, so Kern's team analyzed p53 activity triggered by the chemicals found in liquid smoke. Postdoctoral fellow Zulfiquer Hossain tracked down the chemicals responsible for the p53 activity. The strongest p53 activity was found in two chemicals: pyrogallol and gallic acid. Pyrogallol, commonly found in smoked foods, is also found in cigarette smoke, hair dye, tea, coffee, bread crust, roasted malt and cocoa powder, according to Kern. Gallic acid, a variant of pyrogallol, is found in teas and coffees.

Kern says that more studies are needed to examine the type of DNA damage caused by pyrogallol and gallic acid, but there could be ways to remove the two chemicals from foods and flavorings.

"We found that Scotch whiskey, which has a smoky flavor and could be a substitute for liquid smoke, had minimal effect on p53 activity in our tests," says Kern.

Liquid smoke, produced from the distilled condensation of natural smoke, is often used to add smoky flavor to sausages, other meats and vegan meat substitutes. It gained popularity when sausage manufacturers switched from natural casings to smoke-blocking artificial casings.

Other flavorings like fish and oyster sauces, tabasco and soy sauces, and black bean sauces showed minimal p53 effects in Kern's tests, as did soybean paste, kim chee, wasabi powder, hickory smoke powders and smoked paprika.

Funding for the study was provided by the National Institutes of Health's National Cancer Institute (CA62924) and the Everett and Marjorie Kovler Professorship in Pancreas Cancer Research.

In addition to Kern, Gilbert and Hossain, other scientists involved in the research include Kalpesh Patel, Soma Ghosh, and Anil Bhunia from Johns Hopkins.

On the Web:

Media Contacts:
Vanessa Wasta, 410-614-2916
Amy Mone, 410-614-2915

Vanessa Wasta | EurekAlert!
Further information:

Further reports about: Cancer DNA DNA-damaging food products gallic acid human cell p53 activity

More articles from Life Sciences:

nachricht Novel mechanisms of action discovered for the skin cancer medication Imiquimod
21.10.2016 | Technische Universität München

nachricht Second research flight into zero gravity
21.10.2016 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

Im Focus: Ultra-thin ferroelectric material for next-generation electronics

'Ferroelectric' materials can switch between different states of electrical polarization in response to an external electric field. This flexibility means they show promise for many applications, for example in electronic devices and computer memory. Current ferroelectric materials are highly valued for their thermal and chemical stability and rapid electro-mechanical responses, but creating a material that is scalable down to the tiny sizes needed for technologies like silicon-based semiconductors (Si-based CMOS) has proven challenging.

Now, Hiroshi Funakubo and co-workers at the Tokyo Institute of Technology, in collaboration with researchers across Japan, have conducted experiments to...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Resolving the mystery of preeclampsia

21.10.2016 | Health and Medicine

Stanford researchers create new special-purpose computer that may someday save us billions

21.10.2016 | Information Technology

From ancient fossils to future cars

21.10.2016 | Materials Sciences

More VideoLinks >>>