Regulating the master regulator: Controlling heat shock factor 1 as a chemotherapy approach

Described is the role that heat shock factor 1 (HSF1) plays in regulating cellular stress. Focusing on the current state of the HSF1 field in chemotherapeutics we outline the cytoprotective role of HSF1 in the cell. Summarizing the mechanism by which HSF1 regulates the unfolded proteins that are generated under stress conditions provides the background on why HSF1, the master regulator, is such an important protein in cancer cell growth. Summarizing siRNA knockdown results and current inhibitors provides a comprehensive evaluation on HSF1 and its current state. One set of molecules stands out, in that they completely obliterate the levels of HSF1, while simultaneously inhibiting heat shock protein 90 (Hsp90). These molecules are extremely promising as chemotherapeutic agents and as tools that may ultimately provide the connection between Hsp90 inhibition and HSF1 protein levels.