Effects of ginseng and Ginkgo biloba on the efficacy of 5-flurouracil in colon cancer cells

The most common chemotherapeutic agent used to treat colorectal cancer (CRC) is 5-flurouracil (5-FU); however, the efficacy of this drug can be as low as 8 percent. Several new combinations of drugs with 5-FU and new methods of administering the drug have been attempted to increase the drug's efficacy and decrease its side effects. Cancer patients have also attempted to aid in their healing and improve their quality of life through the use of complementary and alternative medicine (CAM) agents, including herbals, and often do so without informing their healthcare providers. The use of CAM agents may decrease the efficacy of their allopathic treatments. Therefore, this study examines the efficacy of 5-FU in combination with the herbals ginseng (Panax quinquefolius) and two of its ginsenosides, Rg3 and Rg5, and a Ginkgo biloba extract (EGb 761) to determine any adverse or beneficial effects with 5-FU treatment in the HT-29 and HCT-15 CRC cells. Four separate combination studies were performed using different time points of administration of the 5-FU and herbals. It was determined that none of the herbal combinations decreased the efficacy of 5-FU treatment as measured by overall cell growth, and several combinations appeared to enhance its efficacy, as observed through decreased cell growth and increased levels of apoptosis. The in vitro results demonstrate that these herbals appear to be safe for cancer patients to use during 5-FU treatment, and that they may enhance the efficacy of the chemotherapy.