Kushui Rose (R. Setat x R. Rugosa) decoction exerts antitumor effects in C. elegan by downregulating Ras/MAPK pathway and resisting oxidative stress

Kushui rose (R. Setat x R. Rugosa) (KR) is a traditional Chinese medicine proven to be a potent antioxidant, and used for thousands of years. Approximately 30% of all human cancers relevant to mutational activated Ras, and over-activated Ras are accompanied by increased accumulation of reactive oxygen species (ROS). Thus, one way of developing anticancer drugs is to reduce ROS accumulation. Therefore, KR was predicted to have potential to combat over-activated Ras-related cancer. C. elegan with let-60(gf)/ra mutant, which exhibited tumor-like symptoms of the multivulva phenotype, was employed to determine the effect of KR on Ras/MAPK pathway. Other strains of worms and H(2)DCF-DA dye were also applied to study the antioxidant stress capacity of KR. This study was aimed to determine whether KR has a potential effect on combat over-activated Ras-related cancer through resistance to oxidative stress. Our results showed that Kushui rose decoction (KRD) has potent antioxidant activity in vitro, and can inhibit over-activated Ras in vivo Further, KRD significantly suppressed over-activated Ras/MAPK pathway by regulating oxidative stress-related proteins, such as forkhead transcription factor (DAF-16), glutathione S-transferase-4 (GST-4), superoxide dismutases (SODs) and heat shock protein-16.2 (HSP-16.2). However, essential oil and hydrosol of KR had no effect on over-activated Ras. Thus these results reminded us that people usually soak rose in hot water to prepare 'rose tea' as an effective way for health care. Thus, KRD was demonstrated to be a potential drug candidate for combating over-activated Ras-related cancer as an antioxidant.