Neuroblastoma is a common childhood cancer that mutates from immature nerve cells. Recently, a study published in the International Journal of Biological Sciences found that ginsenoside Rk1 can induce apoptosis in neuroblastoma cells, making it a promising treatment for neuroblastoma.
Ginsenosides are the main bioactive ingredients in ginseng that exhibit a wide range of pharmacological activities, including anti-inflammatory, antioxidant, anticancer effects.
There are differences in the activity between different ginsenosides. Ginsenosides that are naturally existing in the ginseng, also called prototype ginsenosides or major ginsenosides, are found to possess less stronger activities. Fortunately, though specialized processing, they can be converted into rare ginsenosides (or minor ginsenosides) with higher bioactivity.
Ginsenoside Rk1 is a rare ginsenoside converted through particular processing like heating steaming or acid transformation. Ginsenoside Rg3 can be converted into ginsenoside Rk1 and Rg5, and ginsenoside Rk1 have potent anticancer activities, and it was reported that ginsenoside Rk1 showed higher anticancer effects than Rg5 and Rh4.
As an outstanding ginsenoside of high activity, ginsenoside Rk1 was found to have antitumor activities in many types of tumors such as human hepatocellular carcinoma cells and human melanoma cells.
Given that there are no relevant studies investigating the anticancer effects of ginsenoside Rk1 against neuroblastoma, the research team led by researchers from Chonbuk National University Medical School in Jeonju, Korea selected it as their study subject.
Any promising therapy shall exert cytotoxicity on tumor cells without damaging normal cells. Researchers first investigated the cytotoxic activity of ginsenoside Rk1 in three neuroblastoma cell lines and three normal lines.
In the experiments, they found that ginsenoside Rk1 significantly reduced the survival rate of three neuroblastoma cell lines while it did not inhibit the growth of normal cells. This result suggests that ginsenoside Rk1 is safe to be used to inhibit neuroblastoma cells without damaging normal cells.
Researchers then investigated the anticancer effect of ginsenoside Rk1 in neuroblastoma cells. They observed a decrease in cell invisibility of neuroblastoma in lab experiments and confirmed that this anticancer effect was induced by apoptosis through a variety of pathways including Mitochondrial Membrane Potential and caspase activation.
In addition, ginsenoside Rk1 was found to inhibit tumor invasion, metastasis, and progression in neuroblastoma cells.
To further confirm the anti-cancer effect of ginsenoside Rk1 in vivo, researchers established a mouse model with artificially implanted human neuroblastoma SK-N-BE(2) cells. The experiment results showed that Rk1 treatment significantly inhibited the growth of the tumor, with the tumor weight and volume significantly decreased.
The study revealed that ginsenoside Rk1 exhibit anticancer activity in neuroblastoma cells. The study result is not beyond expectation since many previous studies have found that ginsenosides can induce apoptosis in the tumor cells, inhibit the generation of new blood vessels and metastasis.
This study is pioneering since it is the first to confirm the anticancer effects of ginsenoside Rk1 in neuroblastoma in vivo. The study provides some insight into the potential use of ginsenoside Rk1 in the treatment of neuroblastoma in the future.
Oh, J. M., Lee, J., Im, W. T., & Chun, S. (2019). Ginsenoside Rk1 Induces Apoptosis in Neuroblastoma Cells Through Loss of Mitochondrial Membrane Potential and Activation of Caspases. International journal of molecular sciences, 20(5), 1213. doi:10.3390/ijms20051213