Abstract
The inability of radiotherapy to control tumour growth is still a daunting clinical problem leading to failure of the overall treatment regimens. The fundamental question is; could tumour cells be specifically sensitized to ionizing radiation (IR) by heat or factors exclusively expressed in tumour cells? One such factor, expressed in most tumours and silent in somatic cells, is telomerase. Biochemical and genetic studies have established an association between telomere maintenance and extended life span of human cells mediated through the expression of the catalytic sub-unit of telomerase (hTERT). Because of this, telomerase is an attractive target for inhibition in anti-cancer therapy. Telomeres are maintained by telomerase and hTERT interacts with heat shock protein (HSP) chaperones. This review will focus on the possible role of HSPs and telomerase in sensitizing tumour cells and, thus, enhancing the potential of targeted radiotherapy.