Effect of Rubus coreanus Miquel on prostate tumour growth

• Rubus coreanus Miquel (RCM) was investigated for anti-tumourigenic effect.
• Ripe and unripe RCM reduced prostate tumour growth.
• RCM reduced cell proliferation and induced apoptosis.
• RCM reduced oxidative stress in tumour tissue by increase of antioxidant enzyme activity.
• The anti-tumourigenic mechanism or RCM relied on enhancement of antioxidant capacities.

The rapidly increasing incidence of prostate cancer in Korea has increased awareness of preventive measures, such as dietary supplementation. Unripe Rubus coreanus Miquel (RCM) has been used to improve prostate health. Using nude mice transplanted with a prostate cancer cell line, we investigated whether RCM supplementation was beneficial for inhibiting the formation or growth of prostate tumour, and its mechanisms. RCM effectively restricted tumour growth compared to the control but had no effect on tumour initiation. Ripe and unripe RCM exerted significant reduction in tumour growth compared to the control. The reduction in tumour mass shown in the RCM groups was associated with increased active form of caspase-3, indicating an enhanced caspase-3-mediated apoptotic process. In addition, RCM demonstrated a strong antioxidant capacity through a decrease in lipid peroxidation products. In addition, RCM modulated the activity of endogenous antioxidant enzymes through modest changes. Collectively, our data indicate that RCM is a promising alternative supplementation for limiting the growth of prostate cancer, and its effect is likely to be achieved through the initiation of caspase-3-mediated apoptosis. The antioxidant properties of RCM appear to play an essential role in its anti-proliferative effect on prostate tumours.