HDAC9 and neoplasm: In addition to previously identified targets, such as CSF‐1/CSF‐1R, CD40, and CD47, two members of siglec family, siglec‐10 and siglec‐15, mediate pathways that affect phagocytosis and the effector function of CD8+ T cells, respectively.[82, 217] CD73 and Class IIa HDAC are potential macrophage targets recently discovered, and their blockade has been to exert an anti‐tumor response in mice.[218, 219] Like TAMs, tumor‐associated neutrophils (TANs) is also heterogeneous with different or even opposite functions.[200] In 2009, Fridlender et al.