Anti-cancer Effect of Hot Water Extract from Mycelium in Germanium-enrichedCordyceps Militaris

Cordyceps militaris has been used in traditional Chinese medicine owing to its anticancer and immunomodulatory activities. Germanium compounds have also been shown to be associated with many pharmacological functions, such as antimicrobial, antiviral, antitumor, antimutagenic, and immunomodulating effects. In this study, we examined the biological properties of hot water extract from mycelial liquid culture of germanium-enriched C. militaris (CMGe). CMGe displayed a concentration-dependent antiproliferation activity against four human cancer cell lines. The antiproliferative activity of CMGe was 2−4-fold lower than that of hot water extract from mycelial liquid culture in C. militaris (CM). However, CM had a concentration-dependent cytotoxicity to human bone marrow-derived mesenchymal stem cells (MSCs). Contrastingly, CMGe did not cause any cellular damage to MSCs. MSCs cultured with CMGe displayed an increased proliferative activity with no cytotoxic effect. The oral administration of CMGe inhibited increased tumor volume and weight compared with the control group. CMGe has the potential to be used as an industrial product in medicinal foods as well as in pharmaceutical products.