We observed a declining trend in the number of macrophages in tumor tissues compared to adjacent non-tumor tissues, which might be attributed to the hypoxic environment in the TME that is unfavorable for the growth and aggregation of macrophages (40), or due to physical barriers formed by tumor cells and the secretion of specific immunoregulatory factors in the TME, such as TGF-β and IL-10, that inhibit the activation and recruitment of macrophages. The gene discussed is TGFB1; the disease is neoplasm.