The expression of HLA class I and HLA-DR antigens in tumors was assessed by IHC on formalin-fixed paraffin-embedded tumor specimens using the pan-HLA class I monoclonal antibody EMR8-5 recognizing HLA-A, -B, and -C heavy chains (54), and a HLA-DRβ-specific polyclonal antibody. Here, HLA-DRB1 is linked to neoplasm.