Increased c-fos expression associated with hyperthermia-induced apoptosis of a Burkitt lymphoma cell line.

Hyperthermia (42 - 44 degrees C for 30 min to 1 h) can induce apoptosis in a variety of cell types and tumour cell lines. This process is usually, but not invariably unaffected by RNA and protein synthesis inhibition. C-fos expression has been implicated in the regulation of apoptosis occurring under diverse circumstances. By heating the Burkitt lymphoma cell line, BM 13674, for 43 degrees C for 30 min, approximately 60% of cells underwent apoptosis within 6h of treatment. Co-ordinate with the massive induction of apoptosis, a 10-fold increase in the steady state c-fos mRNA expression occurred.