question: Are tumour specific antigens originating from known protein coding genes?
answer: Heat-shock proteins (HSPs) function as ubiquitous tumour-specific antigens, with the specificity residing in a population of bound peptides that identify the tissue of origin of the HSP. Tumour antigens are mostly of weak immunogenicity, because the vast majority are tumour-associated differentiation antigens already 'seen' by the patient's immune system.