CCL22 and neoplasm: Moreover, M2 macrophage also releases cytokines and chemokines, such as IL-6, TNFα, and CCL22 (Komohara et al., 2016), activates TGF-β signaling pathway (Yin et al., 2019), and promotes angiogenesis and epithelial–mesenchymal transition (Ni and Cerwenka, 2016; Guan et al., 2021), thereby facilitating tumor progression.