In summary, combining decitabine with the HDAC4/5 inhibitor LMK-235 allows for improved CDX2 expression in CRC cells, particularly in cells with a low sensitivity to DNMT inhibition, whereby HDAC5 is directly involved in CDX2 gene expression by localizing to the CDX2 gene promoter region. The gene discussed is HDAC5; the disease is colorectal carcinoma.