The Potential of Siglec Receptors in Cancer Immunotherapy

Abstract

The immune system has the potential to control tumor growth, but the immune responses are often hindered in an intricate tumor microenvironment. Cancer immunotherapy, which includes immune checkpoint blockades to relieve inhibition and cellular therapies to redirect immune cells to attack cancer cells, has improved the treatment for a variety of cancers. However, many types of cancers or partial patients within a sensitive category remain resistant to the currently approved cancer immunotherapies. It is necessary to gain a further comprehensive understanding of immune regulation mechanisms in the tumor, which facilitates the finding of innovative approaches and targets to overcome the resistance. Sialic acid-binding immunoglobulin-type lectins (Siglecs) are a family of immune receptors expressed on most types of immune cells and play vital roles in immune cell signaling. Recent evidence suggests that Siglecs could be a novel type of immune checkpoints and tumor-associated targets for cancer immunotherapy. This review summarizes the latest experimental and clinical evidence on identifying the roles of Siglec receptors in cancer immunotherapy and the ongoing therapeutics to target Siglec receptors and Siglec-sialic acid pathways.