For instance, Wang et al. showed that M2 macrophage expressing CCL18 was associated with the activation of the FAK/PI3K/AKT pathway to promote the proliferation of esophageal squamous cell carcinoma (ESCC) cells, and that inhibiting PI3K by LY294002 to block the above pathway could impede the M2-induced proliferation of ESCC cells [78]. This evidence concerns the gene PTK2 and esophageal squamous cell carcinoma.