To determine whether RGC-32 expression was induced by the tumor microenvironment, additional treatment with the Condition mediums (CMs) of Caco2, HT-29, and HCT-116 cells in the presence of Phorbol 12-myristate 13-acetate (PMA) induced the differentiation of monocyte cell line THP-1 cells into macrophages. This evidence concerns the gene RGCC and neoplasm.