To explain the discordant phenomenon that CFP1 was one indispensable subunit for the H3K4me3 modifying functions of COMPASS whereas its deficiency upregulated the total H3K4me3 expression and significantly repressed the cancer-associated gene expression, we speculated that CFP1 reshaped the H3K4me3 modification signature within the whole genome to induce selective gene activation or inhibition. This evidence concerns the gene CXXC1 and cancer.