BACKGROUNDThe results of recent experimental studies have suggested that frequently continuous administration of certain cytotoxic agents at low doses (a tenth to a third of the maximum tolerated dose), known as 'anti-angiogenic chemotherapy', can increase the efficacy by targeting the tumor microvasculature. Ginsenoside Rg3 has also been proven to have certain anti-angiogenic effects. The aim of this study is to investigate the inhibitory effects of administration of low-dose gemcitabine combined with ginsenoside Rg3 on angiogenesis of mouse Lewis lung carcinoma and the influence of administration on quality of life of mouse.

METHODSA novel mouse model was developed by inoculating Lewis lung carcinoma cells directly into C57B1/6 mice. The mice were treated with low-dose gemcitabine, ginsenoside Rg3, or both agents together respectively. Then angiogenesis and growth of tumor were observed by color Doppler flow imaging (CDFI) and immunohistochemistry.

RESULTSRemarkably, the combined therapy of gemcitabine and ginsenoside Rg3 resulted in better quality of life of mice than either single agent administration. CDFI and immunohistochemistry showed that there were significantly higher tumor necrosis rate and stronger anti-angiogenic effects in combined therapy group than single agent group.

CONCLUSIONSThe combined therapy of low-dose gemcitabine and ginsenoside Rg3 may cooperatively inhibit neovascularization and growth of mouse Lewis lung carcinoma, and it can keep good quality of life of mouse. It may provide a new strategy for cancer therapy.