Astragalus polysaccharide as a potential antitumor immunomodulatory drug (Review)

The management of malignant neoplasms has consistently posed a challenge within the global medical community. Due to the efficacy demonstrated by various immunomodulatory agents in the therapeutic intervention of tumorigenic diseases, immunotherapeutic strategies have emerged as a promising option for the treatment of cancer. Among these, Astragalus polysaccharide (APS), which is a pharmacologically potent constituent of Astragalus membranaceus root, has received considerable attention as a staple in Traditional Chinese Medicine because of its antitumor applications. APS exhibits antitumor and immunomodulatory properties, regulates immune cells, alters cellular functional activity and markedly enhances immune responsiveness, thereby improving the tumor immune microenvironment and augmenting the cytotoxic capability of immune cells against malignant cells and optimizing antitumor efficacy. The present review summarizes the role of APS in antitumor immunity, particularly focusing on its capacity to modulate immune cell function and enhance the tumor immune microenvironment, and elucidates the underlying antitumor mechanisms. In addition, the immunoregulatory effects and inhibitory actions of APS on tumor growth across various types of malignancies are assessed to provide a scientific rationale for the clinical application of APS as an adjunct to antitumor pharmacotherapy.