Heat stress: A risk factor for skin carcinogenesis

• Heat stress may be a risk factor for skin carcinogenesis.
• Heat activates Heat Shock Proteins (HSPs).
• HSPs influence signalling pathways of cell proliferation, survival and apoptosis.
• Heat stress and UV may synergistically promote transformation of skin cells.

Recent evidence suggests that heat stress may also be a risk factor of skin carcinogenesis. Heat stress causes activation of heat shock proteins (HSPs), chaperone proteins which prevent cells from undergoing apoptosis and ensuring their cellular function. However, HSPs recruitment may also have deleterious effects particularly if the cells rescued from apoptosis carry oncogenic mutations. We hypothesise that exposures to both heat and UV induce skin cancer(s) by concomitant expression of HSPs and oncogenic mutant proteins. Here we review studies demonstrating that heat stress-activated heat shock proteins such as HSP72 and HSP90 can influence signalling pathways such as MAPK, JNK and p53, which are all involved in regulating cell proliferation, survival and apoptosis.