Elderberry and Cancer

Elderberry, or black elder, is a flowering shrub that has historically been used for its medicinal properties throughout the world, including as far back as ancient Egypt.¹ European elderberry (Sambucus nigra) is the most well-studied species, although other varieties exist, including the plant native to the Americas, American elderberry (Sambucus canadensis) and the dwarf variety (Sambucus ebulus L).^2,3

Extracts made from the berries and other parts of the elderberry plant contain compounds such as anthocyanins, flavonoids, and polyphenolics, which are thought to impart its medicinal properties.^1,3 Currently, elderberry extract is probably most well known for its antiviral properties, and commercial preparations are available to purchase as a supplement to prevent infections or to potentially shorten the duration of symptoms — although in-human data are mixed about its efficacy.¹

Some of the chemical constituents of elderberry extract are known to have antiproliferative properties, which has led to a few in vitro studies on the effect of elderberry extract or its chemical constituents on cancer cells.

Anticancer Properties

There are no in-human studies or animal studies that have evaluated whether elderberry extract can prevent or treat cancer. However, several in vitro studies have been conducted that suggest that elderberry extract may have modest anticancer effects.

In a study with human keratinocytes, treatment of cells with elderberry extract resulted in decreased production of VEGF, a protein required for angiogenesis.⁴ Angiogenesis is a critical process that results in the development of new blood vessels, which is important for supplying blood to growing tumors.

Another study treated human colon cancer cells with elderberry extract high in anthocyanins, which inhibited cancer cell growth.⁵ However, elderberry was less effective than other plant extracts, including purple corn, chokeberry, bilberry, purple carrot, and grape. In a different study, an anthocyanin-rich elderberry extract also inhibited the proliferation of mouse melanoma cells in a dose-dependent manner.⁶ The extract caused apoptosis, or cell death, of the melanoma cells.

A study of human breast cancer cells and human colon cancer cells demonstrated that elderberry extract high in triterpenoid acids resulted in cell death.⁷ In addition, another fraction of the elderberry extract that contained oleanolic acid resulted in reduced migration of breast cancer cells, suggesting it may inhibit metastasis.

Conclusions

There are several in vitro studies that suggest that elderberry extract may have some modest anticancer properties. However, elderberry extract has not been studied in animals or humans, therefore, its effect on the prevention or treatment of cancer is unknown. Side effects such as nausea, vomiting, and diarrhea have been reported, typically as a result of overdosage, using uncooked fruit, or using a part of the plant that is toxic.¹

References

1. Porter RS, Bode RF. A review of the antiviral properties of black elder (Sambucus nigra L.) products. Phytother Res. 2017;31(4):533-554.
2. Jabbari M, Daneshfard B, Emtiazy M, Khiveh A, Hashempur MH. Biological effects and clinical applications of dwarf elder (Sambucus ebulus L): a review. J Evid Based Complementary Altern Med. 2017;22(4):996-1001.
3. Thole JM, Burns Kraft TF, Sueiro LA, Kang Y -H, et al. A comparative evaluation of the anticancer properties of European and American elderberry fruits. J Med Food. 2006;9(4):498-504.
4. Roy S, Khanna S, Alessio HM, et al. Anti-angiogenic property of edible berries. Free Radic Res. 2002;36(9):1023-1031.
5. Jing P, Bomser JA, Schwartz SJ, He J, Magnuson BA, Giusti MM. Structure-function relationships of anthocyanins from various anthocyanin-rich extracts on the inhibition of colon cancer cell growth. J Agric Food Chem. 2008;56:9391-9398.
6. Rugină D, Hanganu D, Diaconeasa Z, et al. Antiproliferative and apoptotic potential of cyanidin-based anthocyanins on melanoma cells. Int J Mol Sci. 2017;18:949.
7. Gleńsk M, Czapińska E, Woźniak M, et al. Triterpenoid acids as important antiproliferative constituents of European elderberry fruits. Nutr Cancer. 2017;69:643-651.