ULBP2 and prostate carcinoma: In fact, NKG2D ligand (MICA/B and ULBP-2) gene expression was remarkably induced with 2.5 mM VPA both on malignant (pancreatic carcinoma cells Panc89 and prostate carcinoma cells PC-3) and non-malignant cells (PBMC and γδ T cells).