Celery, artichokes and herbs, such as Mexican oregano, contain apigenin and luteolin, flavonoids that kill human pancreatic cancer cells, U.S. researchers say. Elvira de Mejia, a professor of food chemistry and food toxicology at the University of Illinois, and Jodee Johnson, a doctoral candidate in de Mejia\'s lab who has graduated, found using the flavonoids as a pre-treatment before administering a chemotherapeutic drug inhibited an enzyme that facilitated killing human pancreatic cancer cells. \"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,\" de Mejia said in a statement. The scientists found apigenin inhibited an enzyme called glycogen synthase kinase-3 beta, which led to a decrease in the production of anti-apoptotic genes in the pancreatic cancer cells. Apoptosis means that the cancer cell self-destructs because its DNA has been damaged. In one of the cancer cell lines, the percentage of cells undergoing apoptosis went from 8.4 percent in cells that had not been treated with the flavonoid to 43.8 percent in cells that had been treated. In this case, no chemotherapy drug had been added, the researchers said. Pancreatic cancer patients would probably not be able to eat enough flavonoid-rich foods to raise blood plasma levels of the flavonoid to an effective level, but drugs might achieve the needed concentrations, de Mejia said. However, prevention of this disease is another story. \"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,\" de Mejia said. The findings were published online in Molecular Nutrition and Food Research.