CD24, also known as heat stable antigen or small-cell lung carcinoma cluster 4 antigen, is a heavily glycosylated glycosylphosphatidylinositol-anchored surface protein and is expressed on B cells, T cells, keratinocytes, and myofiber synaptic nuclei and is upregulated in a wide variety of cancers. CD24 is a potent anti-phagocytic, ‘don’t eat me’ signal that is capable of directly protecting cancer cells from attack by Siglec-10-expressing macrophages.
Siglec-10 as an innate immune checkpoint that is essential for mediating anti-tumor immunity and provides evidence for the therapeutic potential of CD24 blockade, with promise for the treatment of ovarian and breast cancers.