University of Illinois scientists Jodee Johnson and Elvira Gonzalez de Mejia found in two in vitro studies that celery and artichokes contain apigenin and luteolin, flavonoids that kill human pancreatic cancer cells by inhibiting an important enzyme.
They found the same phenomenon in herbs, especially Mexican oregano.
Big increase in cancer cell destruction
“Apigenin alone induced cell death in two aggressive human pancreatic cancer cell lines. But we received the best results when we pre-treated cancer cells with apigenin for 24 hours, then applied the chemotherapeutic drug gemcitabine for 36 hours,” said de Mejia.
The flavonoid apigenin inhibited the enzyme glycogen synthase kinase-3β (GSK-3β), leading to fewer anti-apoptotic genes in the pancreatic cancer cells, thus increasing the number of cells undergoing apoptosis.
Apoptosis means self-destruction of the cancer cell because its DNA has been damaged.
Cells undergoing apoptosis went from 8.4% before flavonoid treatment to 43.8% after a 50-micromolar dose, and this was without any chemotherapy drug.
Hard to eat enough to get the effect
The scientists said that patients would not be able to eat enough flavonoid-rich foods to achieve the desired effect, but the research could pave the way for new drugs or supplements.
However flavanol-rich foods may still help to reduce the chances of contracting the disease, added the researchers.
“If you eat a lot of fruits and vegetables throughout your life, you’ll have chronic exposure to these bioactive flavonoids, which would certainly help to reduce the risk of cancer,” said de Meija.
Better as pre-treatment
Johnson said that the flavonoids worked best as a pre-treatment for pancreatic cancer rather than using them with chemotherapeutic drugs simultaneously.
“Even though the topic is still controversial, our study indicated that taking antioxidant supplements on the same day as chemotherapeutic drugs may negate the effect of those drugs,” she said.
When used simultaneously, the flavonoids act as antioxidants and compete with the pro-oxidant activity of chemotherapeutic drugs, said the researchers.
The work was funded by the US Department of Agriculture (USDA).
Mol. Nutr. Food Res. 2013, 00, 1–16
‘Flavonoid apigenin modified gene expression associated with inflammation and cancer and induced apoptosis in human pancreatic cancer cells through inhibition of GSK-3β/NF-κB signaling cascade’
Food and Chemical Toxicology, Vol. 60, October 2013, p 83–91
‘Interactions between dietary flavonoids apigenin or luteolin and chemotherapeutic drugs to potentiate anti-proliferative effect on human pancreatic cancer cells in vitro’
Authors: Jodee Johnson and Elvira Gonzalez de Mejia