Gene profiling of the cell death induced by heat stress in HSC-3 human oral squamous carcinoma cells

Hyperthermia is widely used to treat patients with various cancers. The 42.5˚C is well known as inflection point of hyperthermia and generally up to 42˚C of hyperthermia is used in clinical case to combine with other therapy. Here, the effects of heat stress at 42 or 44˚C for 90 min on the gene expression in HSC-3 human oral squamous carcinoma cells were investigated using an Affymetrix GeneChip system. The cells were treated with heat stress (42 or 44°C for 90 min) and followed by incubation for 0, 6, or 12 h at 37°C. The percentage of cell death was 5.0 ± 1.5 (mean ± SD) at 42°C for 12 h and 17.4 ± 0.6 at 44°C for 12 h. Of approximately 47,000 probe sets analyzed, many genes that were differentially expressed by a factor 2.0 or greater were identified in the cells treated with heat stress at 42 and 44°C. HSC-3 human oral squamous carcinoma cells were treated with heat stress (42 or 44°C for 90 min) and followed by incubation for 0, 6, or 12 h at 37°C. Non-treated cells were served as control. Total RNA samples were prepared from the cells. Gene expression was analyzed by an Affymetrix GeneChip® system with a Human Genome U133-plus 2.0 array for analysis of over 47,000 transcripts. Sample preparation for array hybridization was carried out as described in the manufacturer’s instructions.