CD80 and neoplasm: This aspect of macrophage function on tumor cells is not specific to the M2 phenotype as, somewhat contrary to conventional thought, M1-like TAMs (CD80+/CD86+) have also been shown to induce EMT, migration, and invasion in HNC cells by secreting IL-6 and activating signal transducer and activator of transcription 3 (STAT3) in the tumor cells [16].