Immunological aspects of heat shock protein functions and their significance in the development of cancer vaccines

The primary function of intracellular heat shock proteins (HSPs) is to protect the cell by suppressing the effects of various stress factors by either refolding misfolded proteins or blocking apoptosis. After neoplastic transformation, cells overexpress HSPs, which act as factors promoting the neoplastic process by stabilizing proteins responsible for carcinogenesis, however, HSPs can be released into the extracellular environment where they act as important modulators of the immune response. In a tumor microenvironment, extracellular HSPs are able to induce a pro- or anti-neoplastic response, using various mechanisms of affecting immune cells, The study of the role of extracellular HSPs in immunomodulation processes is a very important direction in the search for new methods of cancer treatment. This review summarizes reports on the use of HSPs in immunotherapeutic cancer strategies, in particular in cancer vaccine design.