PVR and plasma cell myeloma: Fionda et al. have recently shown that the inhibition of GSK-3 with LiCl, SB216763, or BIO increased MICA expression at protein and mRNA levels in human multiple myeloma (MM) cell lines, as well as in tumor cells isolated from the bone marrow of MM patients, without significant effects on expression levels of MICB or the DNAM-1 ligand PVR/CD155 [80].