Cancer cell survival facilitated by Heat Shock Factor 1

All cells depend on heat shock proteins to help them properly function when under a variety of physiological stressors. These heat shock proteins or HSPs make sure that proteins produced by the cell are being folded properly and that the proteins do no gather together forming hazardous clumps. This can all contribute to the prevention of neurological disorders and helps maintain good cell health. The HSPs are primarily controlled by heat shock factors, specifically Heat Shock Factor 1 or HSF1. It was already known that cancer cells used HSPs when exposed to stressors but the role played by HSF1 in controlling the HSPs was unknown. Research, done at the Whitehead Institute for Biomedical Research in Cambridge, Massachusetts, recently tested the effects of the presence of HSF1 on cancer cells. In mice, they found that HSF1 dramatically limited spontaneous tumor formation initiated by either the p53 tumor suppressor gene or activation of mutations of the H-Ras proto-oncogene. “These results suggest that HSF1 is necessary for cells to become cancerous.” They also found that reducing the amount of HSF1 in previously established human cancer cell lines impaired growth and survival of these cells, while having little effect on normal cells. The loss of the protein affects the cell’s rate of glucose intake and protein production, affecting the ability of the cell to continue rapid proliferation. HSF1 coordinates a network of core cellular functions in the cancerous cells, making them more dependent on HSF1 then normal cells.
This article is rather interesting because it shows the complex dual function of a protein. On one hand it helps healthy cells survive under harsh conditions, preventing a variety of disorders and enabling the continuation of proper physiological functions, but on the other hand it aids in the survival and growth of cancer, which ultimately hurts those other healthy cells. It is also interesting because this presents a new potential treatment of cancer. The researchers believe that through short, intense treatments of HSF1 inhibitors, cancer growth could be stopped without leaving patients too vulnerable to neurodegeneration and other problems induced by cell stress. This approach is exciting because it would actually target the cancer cells and help destroy them instead of current methods of removal that usually take healthy cells as well.

Heat Shock Factor 1 Is a Powerful Multifaceted Modifier of Carcinogenesis
Published in Cell (Volume 130, Issue 6, 21 September 2007, Pages 1005-1018):
http://www.cell.com/content/article/abstract?uid=PIIS0092867407009579
(click on Full text at left to see complete article)

Summary Article from Science: “Cancer Cells Chill Out to Survive” http://sciencenow.sciencemag.org/cgi/content/full/2007/920/1