Radiofrequency ablation, heat shock protein 70 and potential anti-tumor immunity in hepatic and pancreatic cancers: a minireview

BACKGROUND: Radiofrequency ablation (RFA) is a minimally invasive surgical procedure which has widespread popularity in the treatment of hepatic and pancreatic cancers. Increased evidence indicates that RFA stimulates anti-tumor immunity, possibly through the induction heat shock protein 70 (HSP70) expression. HSP70 has the capacity to affect the immunogenicity of tumor cells, to chaperone antigenic peptides and deliver these into antigen presentation pathways within antigen-presenting cells, and to activate and regulate innate and adaptive immunity, which makes it useful in immunotherapeutic strategies for the treatment of cancers. DATA SOURCES: An English-language literature search was conducted using MEDLINE (1991-2010) on anti-tumor immunity, heat shock protein 70, radiofrequency ablation, hepatic cancer, pancreatic cancer, and other related subjects. RESULTS: RFA has an increasing application in the surgical treatment of hepatic and pancreatic cancers. Increased evidence indicates that RFA can induce the expression of HSP70 which possesses properties that enable it to influence a variety of immunological processes. Tumor-derived HSP70 is regarded as a potent adjuvant facilitating presentation of tumor antigens and induction of anti-tumor immunity. CONCLUSIONS: This review addresses the potential association of RFA, HSP70, and anti-tumor immunity in treatment of hepatic and pancreatic cancers. To establish direct evidence of a potential association of RFA, HSP70, and anti-tumor immunity in hepatic and pancreatic cancers, further investigations should be conducted.