SIRPA and neoplasm: have demonstrated that soluble factors derived from hepatomas trigger transient activation of newly recruited macrophages and reduce SIRPα expression, thereby inducing these cells to produce a large amount of cytokines, in turn leading to the down‐expression of SIRPα on macrophages and ultimately create an inflammatory environment supporting tumor progression.44 Their findings suggest that there is a fine‐tuned collaborative action between SIRPα expression on macrophages and tumor progression.