Hypophosphorylated TRIM71 facilitated K48-linked polyubiquitination and proteasome-mediated degradation of the antigen peptide-loading complex (PLC) components (e.g., tapasin, transporter associated with antigen processing 1 (TAP1), TAP2, and calreticulin (CALR)) and inherent tumor suppressors Rb and p53. This evidence concerns the gene HSPG2 and neoplasm.