CD24 is a highly glycosylated cell surface protein that is anchored to the cell membrane via a glycosyl-phosphatidylinositol (GPI) anchor. It is widely expressed in various cell types, including hematopoietic cells such as B cells, T cells, granulocytes, dendritic cells, and macrophages, as well as non-hematopoietic cells like keratinocytes and neurons. CD24 plays a crucial role in immune cell maturation and regulation of immune responses. In cancer, CD24 is overexpressed on tumor cells and interacts with the inhibitory receptor Siglec-10 on immune cells, helping tumor cells evade immune detection and attack. This interaction has led to its exploration as a potential target for cancer immunotherapy, with promising results from clinical trials of monoclonal antibodies and other targeted therapies.