HDACi such as sodium butyrate, TSA, and trapoxin A among others upregulate MHC class I and class II proteins, CD40, CD80, and CD86 antigens necessary for costimulation, as well as adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1) on acute myeloid leukemic (AML) cells, human neuroblastoma tumour cells, and mouse plasmacytoma cells in vitro [93, 94]. This evidence concerns the gene ICAM1 and plasmacytoma.