Panax notoginseng Inhibits Tumor Growth through Activating Macrophage to M1 Polarization

Among the herbal ingredients of HangAmDan-B, a medicinal formula that redirects macrophages to become tumoricidal effectors, we found that Panax notoginseng (Burk.) F. H. Chen is the active component responsible for its macrophage-mediated antitumor activity. The water extracted roots of P. notoginseng (PN) did not affect the viability of RAW264.7 murine macrophage-like cells and murine Lewis lung carcinoma (LLC) cells up to a concentration of 100μg/mL. However, the transfer of culture media from PN-treated RAW264.7 cells suppressed the growth of LLC cells. The expression of classically activated (M1) markers, such as interleukin (IL)-1β, monocyte chemotactic protein (MCP)-1, tumor necrosis factor (TNF)-α, and inducible nitric oxide synthase (iNOS), was increased by PN treatment. The expression of alternatively activated (M2) markers including CD206, IL-10, and β-N-acetylhexosaminidases (YM-1) was reduced by PN treatment in the presence of IL-4. Flow cytometry also revealed that PN drives M1 activation of...