CD38 and plasma cell myeloma: Importantly, the effect of tinostamustine on NKG2D ligands from primary myeloma cells was similar to that found in cell lines, especially with respect to MICA, since in the vast majority of samples, tinostamustine increased the expression of this ligand, including some in which CD38 decreased after tinostamustine treatment (e.g., patients 2249 and 2188).