HDAC1 and Merkel cell skin cancer: Upon a 6-hour treatment of 3 VP-MCC cell lines (MKL-1, MKL-2, and WaGa), rapid and selective downregulation of VP-MCC CR TFs was evident in all 3 cell lines upon treatment with the HDAC1/2/3 inhibitors panobinostat and dacinostat, while mocetinostat had a mild and mixed effect on the transcription of CR TFs (Figure 7A and Supplemental Figure 8, F, H, and I).