Prognostic significance of CD47 in human malignancies: a systematic review and meta-analysis

CD47, also known as integrin-associated protein (IAP), is a transmembrane protein belonging to the immunoglobulin superfamily (1). CD47 is widely expressed on the surfaces of normal cells, especially hematopoietic cells. It interacts with signal regulatory protein alpha (SIRPα) to activate a signaling cascade in various phagocytic cells, including dendritic cells and macrophages (2). CD47 is overexpressed in a variety of hematopoietic malignancies and solid tumors, and appears to promote tumor proliferation, progression, and metastasis (3-5)