M1 macrophage-related genes include IL-6, IL-8, CD80, PIM1, RTP4, and SLC11A1, and studies have shown that after metformin treatment, the expression of M1-related factors in tumor cells can be enhanced or weakened, thus affecting the prognosis of the tumor (Chiang et al., 2017). This evidence concerns the gene PIM1 and neoplasm.