Echinacea (Asteraceae family) species is known to be immunostimulatory and was studied in patients with advanced cancer.This is believed to be the first study of echinacea on cancer cell lines in the laboratory. Cytotoxic effects and the ability of echinacea to cause apoptosis (a natural cell suicide) in cancer cells were evaluated. The three common medicinal echinaceas were tested as follows: Echinacea angustifolia, Echinacea purpurea, and Echinacea pallida.
The echinacea species were tested against pancreatic cancer and colon cancer cell lines. Echinacea is already used in conventional therapy of gastrointestinal, pancreatic, and colon cancer patients.
All three species of echinacea were effective against the cancer cells, especially Echinacea pallida, which contains mainly a class of compounds called polyacetylenes with very little alkylamides; whereas E. angustifolia and E. purpurea contain mainly alkylamides. This difference may account for the stronger effect of E. pallida and there is evidence that the polyacetylenes of E. pallida promote apoptosis, a natural form of cell suicide for abnormal cells, such as cancer cells.
Echinacea alkylamides have been shown to inhibit COX-1, COX-2, and 5-lipoxygenase enzymes. The alkylamides reduce the production of eicosanoids, which reduces the risk of certain cancers, especially colorectal cancers.
Echinacea has anti-inflammatory, immunostimulatory, antioxidant, and wound healing properties. The arabinogalactans and alkylamides in echinacea increase the number of natural killer cells. The authors state that the immunostimulatory effects of echinacea last only a few weeks and with chronic use echinacea may be immunosuppressive.
CONCLUSION: Three varieties of echinacea show evidence on testing cancer cell lines in culture that they could be useful in the treatment of cancers. The Echinacea pallida was especially effective, possibly due it its different chemical composition.