Effects of Kuan-Sin-Yin decoction on immunomodulation and tumorigenesis in mouse tumor models

Background: Complementary therapies are widely used among cancer patients. Kuan-Sin-Yin (KSY) decoction, a popular qi-promoting herbal medicine, was constituted with several herbs known to exhibit immunomodulating or anticancer activity. After combining these herbs as a compound formula, it is necessary to reassess the immunomodulation effects, the effects on tumor growth, and possible toxicity of KSY. Methods: The anti-cancer effects of KSY in vivo were determined by measuring the tumor volumes, anticancer-associated cytokines (IFN-gamma, TNF-alpha, IL-2, and IL-12), accumulation of tumor infiltrating leukocytes (TILs), proliferation and apoptosis-related molecular markers (Ki-67, p53, p21, activated caspase 3, and cleaved PARP), and an in situ TUNEL assay. The body weight and serum chemistry of treated mice were also assessed. In vitro, the effects of KSY were evaluated using MTT assay, BrdU incorporation assay and cell growth curve. Results: In vivo, KSY suppressed bladder or lung cancer growth but did not promote the production of cytokines nor increase the accumulation of TILs. The expression of p53 and p21 in KSY-treated mice were increased. The numbers of apoptotic tumor cells and the expression of apoptosis marker proteins (Caspase 3 and cleaved PARP) were not significantly elevated after KSY treatment. In vitro, the viability and proliferation of tumor cells, but not normal cells, were suppressed by KSY treatment. No significant toxicity was found in KSY-treated mice. Conclusions: KSY suppressed the tumor growth in vivo and in vitro, which resulted from its cytostatic effects on cancer cells, rather than the induction of anti-cancer immunity. Under these experimental conditions, no apparent toxicity was observed.