The M2-polarized macrophages have the ability to enhance the growth and formation of blood vessels in tumor tissues, sustain the characteristics of cancer stem cells, and hinder the immune response against tumors by producing PD-L1 or immunosuppressive substances that suppress the activity of cytotoxic T lymphocytes (CTLs) [[59], [60], [61]]. The gene discussed is CD274; the disease is neoplasm.