Inhibition of Tumor Growth in Vitro by a Combination of Extracts from Rosa Roxburghii Tratt and Fagopyrum Cymosum

Objective: Traditional Chinese herbal medicines have a very long history. Rosa roxburghii Tratt andFagopyrum cymosum are two examples of plants which are reputed to have benefits in improving immuneresponses, enhancing digestive ability and demonstrating anti-aging effects. Some evidence indicates that herbalmedicine soups containing extracts from the two in combination have efficacy in treating malignant tumors.However, the underlying mechanisms are far from well understood. The present study was therefore undertakento evaluate anticancer effects and explore molecular mechanisms in vitro.
Methods: Proliferation and apoptosiswere assessed with three carcinoma cell lines (human esophageal squamous carcinoma CaEs-17, human gastriccarcinoma SGC-7901 and pulmonary carcinoma A549) by MTT assay and flow cytometry, respectively, afterexposure to extract from Rosa roxburghii Tratt (CL) and extract from Fagopyrum cymosum (FR). IC30 of CL andFR were obtained by MTT assay. Tumor cells were divided into four groups : control with no exposure to CLor FR; CL with IC30 CL; FR with IC30 FR; CL+FR group with 1/2 (IC30 CL + IC30 FR). RT-PCR and Westernblot analysis were used to detect the expression of Ki-67, Bax and Bcl-2 at mRNA and protein levels.
Results:Compared with the CL or FR groups, the combination of CL+FR showed significant inhibition of cell growthand increase in apoptosis; the mRNA and protein expression levels of Ki-67 and Bcl-2 in CL+FR group wereall greatly decreased, while the expression of Bax was markedly increased.
Conclusions: These results indicatethat the synergistic antitumor effects of combination of CL and FR are related to inhibition of proliferation andinduction of apoptosis.