As CIITA has been shown to potently enhance immunogenicity of tumour cells of different histotypes and distinct MHC genotypes by triggering tumour-specific CD4+ T cells [60], we can also hypothesise that the level of MHC-II molecules was too low to bind the viral env antigenic peptides, and might not reach the threshold for CD4+ T-cell stimulation. Here, CIITA is linked to neoplasm.