IL9 and neoplasm: These range from anti-PD-1/PDL-1 therapy for NSCLC patients with abundant M2 infiltrate (Cao et al., 2019), promotion of C9 secretion in AMs to suspend NSCLC progression (Li et al., 2018), IL-9 signaling blockade (Fu et al., 2022), as well as skewing the M2 phenotype toward the M1 phenotype to elevate tumor-fighting properties within the TME (Conway et al., 2016; Cassetta and Pollard, 2018; Almatroodi et al., 2016; Li et al., 2018).