There is increasing evidence that tumors express putative target molecules
for a therapeutic immune reaction. Yet, tumor cells lack the prerequisites
for appropriate antigen presentation and - hence - the immune system does n
ot respond. This difficulty can probably be circumvented when tumor antigen
s are processed by conventional antigen presenting cells. Thus, the identif
ication of immunogenic tumor-associated antigens may allow new modes of vac
cination with the hope of adding a fourth and hopefully powerful weapon to
surgery, radiation and chemotherapy in the fight against cancer.