Synergist for antitumor therapy: Astragalus polysaccharides acting on immune microenvironment

Abstract

Various new treatments are emerging constantly in anti-tumor therapies, including chemotherapy, immunotherapy, and targeted therapy. However, the efficacy is still not satisfactory. Astragalus polysaccharide is an important bioactive component derived from the dry root of Radix astragali. Studies found that astragalus polysaccharides have gained great significance in increasing the sensitivity of anti-tumor treatment, reducing the side effects of anti-tumor treatment, reversing the drug resistance of anti-tumor drugs, etc. In this review, we focused on the role of astragalus polysaccharides in tumor immune microenvironment. We reviewed the immunomodulatory effect of astragalus polysaccharides on macrophages, dendritic cells, natural killer cells, T lymphocytes, and B lymphocytes. We found that astragalus polysaccharides can promote the activities of macrophages, dendritic cells, natural killer cells, T lymphocytes, and B lymphocytes and induce the expression of a variety of cytokines and chemokines. Furthermore, we summarized the clinical applications of astragalus polysaccharides in patients with digestive tract tumors. We summarized the effective mechanism of astragalus polysaccharides on digestive tract tumors, including apoptosis induction, proliferation inhibition, immunoactivity regulation, enhancement of the anticancer effect and chemosensitivity. Therefore, in view of the multiple functions of astragalus polysaccharides in tumor immune microenvironment and its clinical efficacy, the combination of astragalus polysaccharides with antitumor therapy such as immunotherapy may provide new sparks to the bottleneck of current treatment methods.

Anticancer Mechanism of Astragalus Polysaccharide and Its Application in Cancer Immunotherapy

“…In a study on C4H/HeJ mouse splenocytes, APS effectively induced B-cell proliferation through a pathway that was not TLR3-dependent. This stimulatory effect was primarily mediated by immunoglobulins on the cell surface, offering new insights into the specific mechanisms by which APS regulates B cells within the immune system [18].…”

“…It consists of nine monosaccharides, including glucose, galactose, arabinose, and rhamnose, and may contain glucuronic acid and galacturonic acid [16]. Due to its water solubility and low-toxicity characteristics, APS has demonstrated significant biological activities in immune activation and antioxidant, antitumor, antidiabetic, anti-inflammatory, and anti-aging properties; thus, it has great potential for drug discovery in the pharmaceutical and nutraceutical fields [17][18][19][20][21][22][23]. Research indicates that APS is safe and effective for cancer treatment because it enhances the body's immune response, mitigates the side effects of chemotherapy, and activates immune defenses [24,25].…”

Astragalus polysaccharide: implication for intestinal barrier, anti-inflammation, and animal production

“…Additionally, excessive cytokine production aggravates intestine inflammation and intestinal barrier impairment ( 96 ). Interestingly, accumulating evidence reported that APS exerts the potentiality to promote the activities of immune cells (e.g., macrophages, natural killer cells, dendritic cells, T lymphocytes, B lymphocytes, and microglia) and regulates the production of cytokines and chemokines ( 16 , 97 , 98 ). A previous study was conducted to examine the effects of APS ( in ovo injection) on number of immune cells, sIgA, and intestinal immune-related genes expression in broiler chickens.…”

Progress of plant‐derived non‐starch polysaccharides and their challenges and applications in future foods

“…It was concluded that ACP activated immune‐related cells and promoted the apoptosis of tumor cells by relying on the mitochondrial pathway to exert the antitumor effects (Zhang et al., 2023). It has been concluded that polysaccharides exert antitumor effects through four main mechanisms: (1) the prevention of tumorigenesis; (2) the inhibition of tumor cell growth, migration, and invasion; (3) the enhancement of immune function; and (4) the induction of apoptosis and cytotoxicity against tumor cells (S. K. Chen, Wang, et al., 2023; Xu et al., 2023).…”