B2M and cancer: Inference: The research conducted with cancer cells reveals that (1) the proinflammatory cytokine IFN-γ and RA are capable of inducing the surface expression of Face-2 without any involvement of B2m; (2) Face-2 can emerge from the cytoplasm directly and not by dissociation of B2m from Face-1; (3) the downregulation of HLA-Ia Face-1 on human cancer cells occurs concomitantly with the upregulation of Face-2 (Table 2).