HLA-G and neoplasm: Analysis of sorted MC38T/O tumor cells from Dox-treated mice showed elevated levels of Il6, β2-microglobulin (B2m), which associates with the MHC-I complex, and CD137-ligand (Cd137L), a ligand of the costimulatory receptor CD137, which is expressed on effector T lymphocytes (Fig. 6A).