HMGB1 and cancer: We found that the immunological protection afforded to C57BL/6 mice by B16-OVA cells succumbing to 8-MOP plus 4J UVA light is largely compromised not only by the short-hairpin RNA (shRNA)-mediated depletion of CALR or HMGB1 in cancer cells, but also by the pharmacological degradation of extracellular ATP with apyrase and the blockage of IFNAR1 with a specific monoclonal antibody (Fig. 6a–d).