Angiogenesis is the physiological process through which new blood vessels form from pre-existing vessels. Angiogenesis is a fundamental step in the transition of tumors from a benign state to a malignant one, leading to the use of angiogenesis inhibitors in the treatment of cancer.

Hepatocellular carcinoma is the most common form of primary liver cancer in adults. Surgery to remove the tumor (resection) is the preferred treatment for patients with limited disease, but many patients are ineligible for resection because of the location of the tumor within the liver, coexisting medical conditions, or both.

More and more evidence has shown that angiogenesis and disruption of liver vascular architecture have been linked to progression to cirrhosis and liver cancer (HCC) in chronic liver diseases. Thus, drugs which effectively inhibit angiogenesis can prevent the formation of new blood vessels, thereby stopping or slowing the growth or spread of tumors.

Protopanaxadiol (PPD) is a type of dammarane sapogenin, and is mainly extracted from ginseng. Scientists from Jilin University have found that PPD can effectively inhibit the new blood vessel formation (angiogenesis) in mouse model of live cancer, and reduce tumor growth thereafter. The study results were published on Journal of Clinical Hepatology (2006, title: Influences of Protopanaxdiol to Interstitial Microvascular Density and Proliferation Activity of Liver Cancer).

The study used H22 liver cancer cells to establish the liver cancer model on mice, the latter were then randomized into five groups (contro, cyclophosphamide, and PPD at doses of 25, 50 and 100mg/kg). After 2 weeks of drug administration, the results showed the treatment of PPD at all doses reduced the tumor size and weight. At the high dose of 100mg/kg, PPD reduced the tumor to a similar degree as cyclophosphamide. Strikingly, PPD at all doses significantly decreased the blood vessel density in the tumor, which was even much lower than that in the cyclophosphamide gruop.

Considering PPD’s strong inhibitory effect on angiogenesis and tumor growth as well as the clinical significance of angiogenesis in the growth and metastasis of liver cancer, chemo regimens combined with PPD could extend the survival of liver cancer patients.