Green Tea

Understanding How Green Tea Fights Cancer

Dihydrofolate Reductase (DHFR) plays an important role in human physiology. The blocking of its enzymatic activity is a key element in treatment of many diseases, including cancer and AIDS related infections. Recently, researchers at the University of Murcia in Spain (UMU) and the John Innes Center (JIC) in Norwich, England have shown that a compound called EGCG (Epigallocatechin gallate) in green tea prevents cancer cells from growing by binding to the enzyme dihydrofolate reductase (DHFR):

"We have shown for the first time that EGCG, which is present in green tea at relatively high concentrations, inhibits the enzyme dihydrofolate reductase (DHFR), which is a recognized, established target for anti-cancer drugs, " says Professor Roger Thorneley, of JIC. "This is the first time, to our knowledge, a known target for an anti-cancer drug has been identified as being inhibited by EGCG," he added.

"We have identified this enzyme in tumour cells that EGCG targets and understand how it stops this enzyme from making DNA. This means we may be able to develop new anti-cancer drugs based on the structure of the EGCG molecule," Thorneley explained.

The scientists decided to look at ECGC after they realized its structure was similar to a cancer drug called methotrexate. "We discovered that EGCG can kill cancer cells in the same way as methotrexate," Dr Jose Neptuno Rodriguez-Lopez, of UMU, a joint author of the research published in the journal Cancer Research.

EGCG binds strongly to DHFR, which is essential in both healthy and cancerous cells. But it does not bind as tightly as methotrexate, so its side effects on healthy cells could be less severe than those of the drug. Thorneley said EGCG could be a lead compound for new anti-cancer drugs.

CAUTION : large amounts of green tea could decrease the effectiveness of folic acid and that Dihydrofolate Reductase is the enzyme that folic acid supplements are used to target.