Oridonin is a naturally occurring chemical that can be extracted from the Chinese sage bush Isodon rubescens, formerly known as Rabdosia rubescens. It is used in traditional Chinese medicine to block cancer metastasis and recurrence and to overcome therapeutic resistance. Recently, a new study has been completed which looked at its effects on a lung cancer xenograft mouse model.
To begin, the mice were injected subcutaneously with human lung cancer cells. The tumors were allowed to grow and develop to a specified volume prior to beginning treatment. Once the tumors were developed, oridonin was injected intraperitoneally five times each week. In addition, NK-92MI cells were injected intravenously once a week. These “natural killer cells” are a naturally occurring part of an immune system. However, the mouse model used for this experiment does not have a functioning immune system. Therefore, the killer cells were injected during the study.
The results of the study showed that oridonin treatment enhanced the activity of the natural killer cells against all three different cancer cells lines studied. It was also revealed that ordidonin seems to be non-toxic to the liver and kidney. This is exciting because selectively harming only cancer cells without effecting normal cells always proves to be a challenge.
Understanding of the immunostimulatory effect of oridonin on NK cells more thoroughly may help to develop a new lung cancer treatment.