FEB 15, 2021 3:46 PM PST

Green Tea Boosts a DNA-Repairing, Tumor-Suppressing Protein

WRITTEN BY: Carmen Leitch

Green tea has been lauded for its medicinal qualities, though it's been difficult to show that definitively. A new study has suggested that green tea contains an antioxidant that may raise the levels of a natural molecule that cells use to repair DNA and protect against cancer, called p53. The work, which was reported in Nature Communications, investigated the interaction of p53 and a compound in green tea called epigallocatechin gallate (EGCG) and may aid in the development of new cancer therapeutics.

Image credit: Max Pixel

"Both p53 and EGCG molecules are extremely interesting. Mutations in p53 are found in over 50 percent of human cancer, while EGCG is the major antioxidant in green tea, a popular beverage worldwide," said corresponding study author Chunyu Wang, a professor of biological sciences at Rensselaer Polytechnic Institute. "Now we find that there is a previously unknown, direct interaction between the two, which points to a new path for developing anti-cancer drugs. Our work helps to explain how EGCG is able to boost p53's anti-cancer activity, opening the door to developing drugs with EGCG-like compounds."

The p53 molecule can stop the growth of a cell when its DNA is damaged so that damage can be repaired before it's passed on to daughter cells. Cells that are damaged but continue to grow can lead to cancer. It can also trigger a cell death process called apoptosis when cells are damaged beyond repair. Wang described p53 as "arguably the most important protein in human cancer." One end of the p53 molecule is flexible, and therefore, might help the protein interact with different molecules so it can serve different functions.

Antioxidants help repair the damage done by free radicals, which can be helpful or harmful, but are dangerous at high levels when they lead to oxidative stress. Antioxidants counteract oxidative stress. EGCG is known as a natural antioxidant and is abundant in green tea. It's also sold as an herbal supplement.

This study showed that EGCG and p53 interact to stop p53 from being degraded; p53 usually broken down quickly after it encounters a protein called MDM2 and is in a continuous cycle of production and degradation.

"Both EGCG and MDM2 bind at the same place on p53, the N-terminal domain, so EGCG competes with MDM2," explained Wang. "When EGCG binds with p53, the protein is not being degraded through MDM2, so the level of p53 will increase with the direct interaction with EGCG, and that means there is more p53 for anti-cancer function. This is a very important interaction."

"By developing an understanding of the molecular-level mechanisms that control key biochemical interactions linked to devastating illnesses such as cancer and Alzheimer's disease, Chunyu's research is laying the groundwork for new and successful therapies," said Curt Breneman, dean of the Rensselaer School of Science.

Sources: AAAS/Eurekalert! via Rensselaer Polytechnic Institute, Nature Communications

 

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
MAR 10, 2021
Genetics & Genomics
As Diphtheria Cases Rise & More Become Drug Resistant, It May Become a Threat
MAR 10, 2021
As Diphtheria Cases Rise & More Become Drug Resistant, It May Become a Threat
Diphtheria was once a leading cause of death for children; immunization programs eventually changed that for most countr ...
MAR 30, 2021
Immunology
Single-Cell Technology Exposes Melanoma's Weak Spot
MAR 30, 2021
Single-Cell Technology Exposes Melanoma's Weak Spot
The immune system encompasses a powerful arsenal of weapons against pathogenic threats. But what stops healthy tissues i ...
APR 20, 2021
Immunology
Scientists Map the Genetic Landscape of COVID Infections
APR 20, 2021
Scientists Map the Genetic Landscape of COVID Infections
Scientists have identified 65 human immune genes activated during SARS-CoV-2 infection. This finding provides valuable i ...
APR 22, 2021
Genetics & Genomics
A Novel Mechanism of Gene Regulation is Revealed
APR 22, 2021
A Novel Mechanism of Gene Regulation is Revealed
For simplicity's sake, DNA is though of as a double-stranded molecule made of nucleotide bases A, G, C, and T, and RNA a ...
APR 23, 2021
Cell & Molecular Biology
There Are 'Hotspots' of Genomic Repair in Neurons
APR 23, 2021
There Are 'Hotspots' of Genomic Repair in Neurons
It's thought that unlike cell types that are constantly replenishing themselves (like many types of blood cells, for ...
APR 25, 2021
Genetics & Genomics
It's DNA Day!
APR 25, 2021
It's DNA Day!
The genetic instructions that biological organisms use to generate their structures & maintain life are contained in a m ...
Loading Comments...