Towards a better way to die with chemotherapy: role of heat shock protein exposure on dying tumor cells.

The ultimate goal of most anti-tumor therapies is to kill tumor cells. While most of the attention in cancer therapy has been towards enhancing the death of tumor cells, the effect of dying tumors on the immune system has been less studied. Recent studies have suggested that cell death induced by different agents may have distinct consequences for the immune system. One of the immunogenic signals may be the expression of heat shock proteins on dying tumor cells under certain settings. For example, bortezomib(a proteasome inhibitor) induces the expression of heat shock protein 90 (hsp90) on the surface of dying human myeloma tumor cells. Recognition of such tumor cells by antigen presenting dendritic cells leads to the generation of anti-tumor T cells. Harnessing the properties of some anti-tumor agents to induce immunogenic death of tumor cells may facilitate the recruitment of adaptive immunity and promote the durability of anti-tumor effects.