10
Impact Factor
Int J Biol Sci 2024; 20(2):664-679. doi:10.7150/ijbs.85276 This issue Cite
Research Paper
1. State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Safety and Health,National Health Commission Science and Technology Innovation Platform for Nutrition and Safety of Microbial Food, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, China.
2. College of Food Science, South China Agricultural University, Guangzhou 510642, China.
3. Sunnybrook Research Institute, Sunnybrook Health Sciences Centre, Toronto, M4N3M5, Canada.
4. Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, M4N3M5, Canada.
5. Yuewei Edible Fungi Technology Co. Ltd., Guangzhou 510070, China.
* Equal contributions.
Myeloid derived suppressor cells (MDSCs) are known to accumulate in cancer patients and tumor-bearing mice, playing a significant role in promoting tumor growth. Depleting MDSCs has emerged as a potential therapeutic strategy for cancer. Here, we demonstrated that a fungal polysaccharide, extracted from Grifola frondosa, can effectively suppress breast tumorigenesis in mice by reducing the accumulation of MDSCs. Treatment with Grifola frondosa polysaccharide (GFI) leads to a substantial decrease in MDSCs in the blood and tumor tissue, and a potent inhibition of tumor growth. GFI treatment significantly reduces the number and proportion of MDSCs in the spleen, although this effect is not observed in the bone marrow. Further analysis reveals that GFI treatment primarily targets PMN-MDSCs, sparing M-MDSCs. Our research also highlights that GFI treatment has the dual effect of restoring and activating CD8+T cells, achieved through the downregulation of TIGIT expression and the upregulation of Granzyme B. Taken together, our findings suggest that GFI treatment effectively eliminates PMN-MDSCs in the spleen, leading to a reduction in MDSC numbers in circulation and tumor tissues, ultimately enhancing the antitumor immune response of CD8+T cells and inhibiting tumor growth. This study introduces a promising therapeutic agent for breast cancer.
Keywords: Grifola frondosa, polysaccharide, breast cancer, Myeloid derived suppressor cells, CD8+T cells