Structure-activity relationship and anticancer mechanisms of Ganoderma lucidum polysaccharides
灵芝多糖的抗癌构效关系及其抗癌作用机制

Ganoderma lucidum polysaccharides (GLPS) is one of the main anticancer constituents of G. lucidum. Until now, however, the structure-activity correlation and anticancer mechanisms of GLPS are still not well understood. Studies show that GLPS with β-(1→3)-D-glucan structure have anticancer actions. Generally, G. lucidum β-glucans containing higher branching ratio have higher activity, and high molecular weight glucans appear to be more effective than those with low molecular weight. Exceptionally, some polysaccharides with other structures and low molecular weights also have the immunomodulatory and anticancer effects. The role of these active polysaccharides can not be neglected. Studies on immune receptors for GLPS implied that both membrane Ig and TLR4 are required for GLPS-mediated B cell activation, and TLR4 is also involved in GLPS-mediated macrophage activation. Immunity-mediated mechanism is one of the most important contributions to the anticancer action of GLPS, while other possible mechanisms include activation of mitogen-activated protein kinases and the inhibition of angiogenesis, etc.