Herbal medicine is widely used as a complementary therapy in cancer treatment and a large portion of cancer patients were reported to use herbal medicine to enhance the therapeutic effects of the treatment.
A recent study listed 12 natural compounds from herbal medicines that have been reported to exhibit potential immumodulatory effects to fight against cancer.
1. Apigenin
Apigenin, a dietary flavonoid, is naturally present in many fruits, vegetables, and beverages including onions, parsley, oranges chamomile, and tea. It can activate immune cells to inhibit cancer cells in lab and animal studies.
2. Berberine
Berberine, an isoquinoline alkaloid, is mainly derived from medicinal plants like Coptidis chinensis Franch and Phellodendron chinense Schneid.
Berberine is found to be potentially developed as an immune checkpoint inhibitor for immunotherapy against cancers.
Berberine-rich foods include goldenseal, Oregon grape, tree turmeric, etc.
3. Chrysophanol
Chrysophanol is extracted from rhubarb root, Senna leaf and pod, Cascara, Buckhorn, and Aloe. This anthraquinone compound exerts anticancer effects against T‐cell acute lymphoblastic leukemia.
4. Curcumin
Curcumin is a dominant bioactive compound from the rhizomes of Acorus calamus L., Curcuma longa, and Curcuma zedoaria. A growing number of evidence shows that curcumin modulates multiple immune cells including B cells and T cells to fight against various cancer cells.
5. β‐Elemene
β‐Elemene, a volatile terpene, is a constituent of many herbal medicines including Curcuma wenyujin Y. H. Chenet C. Ling and Curcuma Zedoary. It can be sourced from turmeric, celery, mint, citrus fruit and other plants. Researchers have found that β‐Elemene can inhibit tumor growth via modulating PD‐L1 expression in lab and animal studies.
6. Epigallocatechin gallate
Epigallocatechin gallate, a polyphenol, is derived from Camellia sinensis (green tea) which have been used as a natural herbal medicine for thousands of years. Recent preclinical studies show that the combination of epigallocatechin gallate with DNA vaccine might be effective in activating immune response and shinking tumor size.
7. Gallic acid
Gallic acid, a polyphenol, is derived from many natural plants like strawberry, grape, banana, blueberry, walnut, green tea, etc. It can inhibits immune checkpoint to exerts anticancer effects in Non-small cell lung cancer cells and colorectal cancer cells.
8. Ginsenosides
Ginsenosides, a group of dammarane triterpenoids, are the pharmacologically active compounds found in the rhizomes of Panax ginseng, Panax noto-ginseng(Burk.) F. H. Chen, and Cinnamomum cassia Presl. Ginsenosides have hundreds of monomers, and rare ginsenosides Rh2, Rg3, Rk1 and Rh4 have been shown to exert immunomodulatory effects on different tumor cells.
9. β‐Glucans
β‐Glucans, natural polysaccharides, derived from plants, as well as the cell walls of yeast, fungi, and bacteria. β‐Glucans are present in food like barley, oats, whole grains, seaweed, algae, etc.
10. Resveratrol
Resveratrol, a nonflavonoid polyphenol, is derived from plants like grapes, peanuts, soy, and berries. It has been found to exert potent anticancer immune response in cancer treatment.
11. Silibinin
Silibinin, a flavonoid, is derived from Silybum marianum. Milk thistles and artichokes are good source of Silibinin. It has been shown to exert exert immunomodulatory effects in nasopharyngeal carcinoma cells.
12. Triptolide
Triptolide, a diterpenoid epoxide, is an active compound extract from a Chinese medicinal herb Thunder god vine (Tripterygium wilfordii Hook F.). It is a promising chemical for cancer treatment with potent cytotoxicity against tumor cells and and immunodulatory properties.
Medicinal herbs are good sources of remedies and cures for cancer and diseases. We have already found some famous anti-tumor drugs made of chemical compounds of medicinal herbs. The listed 12 natural compounds are promising agent for immunodulation and cancer therapy, and more studies are needed to clarify their molecular mechanisms and clinical effects in human studies.