Methylation status of candidate TSGs in CD34⁻ cells from bone marrow DNA. Promoter methylation of p15^INK4B, CDH-1, DAPK-1, and SOCS-1 was monitored by MSP in 29 patients before treatment (day 0), on days 15 to 16, and on days 28 to 29 of the first cycle of therapy. Red color indicates methylated status, green color indicates unmethylated status, and white color indicates sample was unavailable. No statistically significant association between reversal of candidate TSG methylation status and clinical response to combination therapy with 5AC and entinostat was detected. CR indicates complete response; PR, partial response; HI, hematologic improvement; and NR, no response.