Send to

Choose Destination
Cancer Sci. 2018 Jun 6. doi: 10.1111/cas.13663. [Epub ahead of print]

The CD47-SIRPα signaling system and its application to cancer immunotherapy.

Author information

Division of Molecular and Cellular Signaling, Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, 650-0017, Japan.


Tumor cells evade immune surveillance through direct or indirect interactions with various types of immune cell, with much recent attention having focused on modifying immune cell responses as the basis for the development of new cancer treatments. Signal regulatory protein α (SIRPα) and CD47 are both transmembrane proteins that interact with each other and constitute a cell-cell communication system. SIRPα is particularly abundant in myeloid cells such as macrophages and dendritic cells, whereas CD47 is expressed ubiquitously and its expression level is elevated in cancer cells. Recent studies have shown that blockade of the CD47-SIRPα interaction enhances the phagocytic activity of phagocytes such as macrophages toward tumor cells in vitro as well as results in the efficient eradication of tumor cells in a variety of xenograft or syngeneic mouse models of cancer. Moreover, CD47 blockade has been shown to promote the stimulation of tumor-specific cytotoxic T cells by macrophages or dendritic cells. Biological agents, such as Abs and recombinant proteins, that target human CD47 or SIRPα have been developed and are being tested in preclinical models of human cancer or in clinical trials with cancer patients. Preclinical studies have also suggested that CD47 or SIRPα blockade may have a synergistic antitumor effect in combination with immune checkpoint inhibitors that target the adaptive immune system. Targeting of the CD47-SIRPα signaling system is thus a promising strategy for cancer treatment based on modulation of both innate and acquired immune responses to tumor cells. This article is protected by copyright. All rights reserved.


CD47; cancer immunotherapy; macrophage; phagocytosis; signal regulatory protein α (SIRPα)

Free full text

Supplemental Content

Full text links

Icon for Wiley
Loading ...
Support Center