Kencur Ginger’s Anti-Cancer Effects Revealed

Osaka Metropolitan University scientists demonstrate the anti-cancer properties of Kencur ginger are caused by its bioactive compound, ethyl p-methoxycinnamate (EMC). In mice, this compound reduced cancer cell proliferation at low doses.

Indonesia’s herbal elixir contains Kencur ginger

While chemically synthesized drugs are an integral component of Western medicine, many developing countries around the world rely on medicinal plants to treat or prevent human disease. Several bioactive compounds found in plants have demonstrated anti-cancer properties, including tannins, alkaloids and terpenoids. Such compounds are attractive to researchers developing novel anti-cancer drugs, as conventional treatments – such as chemotherapy – are burdened by the therapy’s cytotoxic effects on healthy cells.

Kaempferia galanga L. – commonly known as Kencur – is a tropical plant that is native to Southeast Asia and belongs to the ginger family. If you’ve traveled to Indonesia, you may have been served  “Jamu”, a herbal drink that is rich in history and cultural significance. One of the primary ingredients in Jamu, which translates to “prayer for health" in old Javanese, is Kencur ginger.

In previous research, Kaempferia galanga L. extract – or KGE – demonstrated anti-cancer effects against Ehrlich ascites tumor cells (EATCs) in mice. The extract was found to fragment the nucleus of the cancer cells, reducing their survival rate. How this anti-cancer effect occurred, however, was not well understood. It was thought to decrease the expression of a protein called mitochondrial transcription factor A (TFAM), a key player in cancer cell proliferation.

Professor Akiko Kojima, a scientist at the Graduate School of Human Life and Ecology at Osaka Metropolitan University, went in search of answers.

The major bioactive compound of Kencur and its extract KGE is EMC. “EMC has a variety of physiological effects, including anti-inflammatory, antioxidant and bactericidal effects,” Kojima and colleagues write. “Previous studies have reported that EMC reduces the viability of MCF-7 breast cancer cells at concentrations over 625 μM.” While this data is encouraging, the concentration of EMC used in these studies was high; Kojima felt concerned that this could induce cell death in cancerous and healthy cells.

In the current study, published in Heliyon, Kojima and team explored the anti-cancer effects of EMC at lower concentrations. “We aimed to elucidate the mechanism underlying Kaempferia galanga L.’s anti-cancer effect by targeting TFAM in EATCs derived from breast cancer. The anti-cancer effects of KGE and EMC were also demonstrated in a mouse tumor model, in which EATC was administered intraperitoneally,” they write.

EMC upregulates p21 and downregulates cyclin D1

Kojima and colleagues’ work in mice found EMC to be the active compound in Kencur that is responsible for the plant’s anti-cancer effects. Low doses of EMC were capable of suppressing cell proliferation by upregulating p21 and downregulating cyclin D1 expression. p21 – a cyclin-dependent kinase inhibitor – promotes cell cycle arrest. Cyclin D1 is a key regulator of the cell cycle and is known to influence the pathogenesis of several different types of cancer, most notably breast cancer.

“EMC also decreases the expression of TFAM, a regulator of mitochondrial function, and is closely associated with cancer cell proliferation,” the researchers say. An “interesting” finding highlighted by the team was that EMC did not cause mitochondrial dysfunction. Instead, they suggest that the reduced expression of TFAM, induced by EMC, might inhibit the cancer cell proliferation by regulating the expression of nuclear genes.

“To the best of our knowledge, this study is the first to report that the natural compound-induced decrease in TFAM expression correlates with the expression levels of cyclin D1 and p21,” Kojima and team state. “Our results indicated that low-dose EMC (100 μM) suppressed cell proliferation without inducing apoptosis and could safely provide anti-cancer effects,” they add, before cautioning that further studies – including clinical trials – are required to confirm that Kencur’s bioactive compounds exert such effects in human patients.

Reference: Sasaki Y, Norikura T, Matsui-Yuasa I, Fujii R, Limantara L, Kojima-Yuasa A. Kaempferia galanga L. extract and its main component, ethyl p-methoxycinnamate, inhibit the proliferation of Ehrlich ascites tumor cells by suppressing TFAM expression. Heliyon. 2023;9(6). doi: 10.1016/j.heliyon.2023.e17588

This article is a rework of a press release issued by Osaka Metropolitan University. Material has been edited for length and content.