title: A systematic review of anticancer effects of radix astragali.
abstract: OBJECTIVE
  To review the anticancer effects of Radix astragali (RA), one of the most commonly used herbs to manage cancer in East Asia, and its constituents and to provide evidence of clinical usage through previously performed clinical studies.
  
  
  METHODS
  Preclinical and clinical studies related to the anticancer effects of RA were searched from inception to November 2013 in electronic databases. Two reviewers independently investigated 92 eligible studies, extracted all the data of studies and appraised methodological quality of clinical trials. The studies were categorized into in vitro and in vivo experimental studies and clinical studies, and analyzed by saponins, polysaccharides, and flavonoids of RA constituents, RA fraction, and whole extract.
  
  
  RESULTS
  In preclinical studies, RA was reported to have tumor growth inhibitory effects, immunomodulatory effects, and attenuating adverse effects by cytotoxic agents as well as chemopreventive effects. Saponins seemed to be the main constituents, which directly contributed to suppression of tumor growth through the activation of both intrinsic and extrinsic apoptotic pathway, modulation of intracellular signaling pathway, and inhibition of invasion and angiogenesis. Flavonoids suppressed tumor growth through the similar mechanisms with saponins. Polysaccharides showed immunomodulatory effects, contributing tumor shrinkages in animal models, despite the low cytotoxicity to cancer cells. Most of the clinical studies were performed with low evidence level of study designs because of various limitations. RA whole extracts and polysaccharides of RA were reported to improve the quality of life and ameliorate myelosuppression and other adverse events induced by cytotoxic therapies.
  
  
  CONCLUSIONS
  The polysaccharides, saponins, and flavonoids of RA, and the whole extract of RA have been widely reported with their anticancer effects in preclinical studies and showed a potential application as a adjunctive cancer therapeutics with the activities of immunomodulation, anti-proliferation and attenuation of adverse effects induced by cytotoxic therapy.
authors.affiliation: Department of Clinical Oncology, College of Korean Medicine, Kyung Hee University Hospital at Gangdong, 892 Dongnamro, Gangdong-gu, Seoul, 05287, Republic of Korea.
authors.forename: Yeehong
authors.initials: Y
authors.lastname: Jung
authors.affiliation: Clinical Research Division, Korea Institute of Oriental Medicine, 1672, Yuseong-daero, Yuseong-gu, Daejeon, 34054, Republic of Korea.
authors.forename: Uimin
authors.initials: U
authors.lastname: Jerng
authors.affiliation: Department of Clinical Oncology, College of Korean Medicine, Kyung Hee University Hospital at Gangdong, 892 Dongnamro, Gangdong-gu, Seoul, 05287, Republic of Korea. sookyung@khu.ac.kr.
authors.forename: Sookyung
authors.initials: S
authors.lastname: Lee
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D027885:Astragalus propinquus; D002986:Clinical Trials as Topic; D004365:Drugs, Chinese Herbal / Q000737:chemistry / Q000627:therapeutic use*; D006801:Humans
chemical_list: D000970:Antineoplastic Agents; D004365:Drugs, Chinese Herbal; C027492:Huang Qi
keywords: Radix astragali; anticancer agents; cancer; systematic review