Among the commonly down‐regulated genes, we found three of the four genes identified in our previous study and commonly down‐regulated in GCT cell lines (TCam‐2, 2102EP, NCCIT, JAR) after romidepsin treatment (NSMAF, RCN1, ZMYND11) (Data S1D).5 Down‐regulation of ARID1A was shown to be the initial step in the romidepsin cascade.11ARID1A was also down‐regulated in TCam‐2‐DHRS2+/+ and TCam‐2‐DHRS2−/− clones, although in the latter one slightly below the set threshold of fold change ≥2 (−1.83‐fold). The gene discussed is ARID1A; the disease is granular cell tumor.