(116q) Hyperthermia Analysis on Human Colorectal Adenocarcinoma Cells

Cancer cells are known to be more sensitive to heat than most normal cells. This characteristic has proven significant in the search for new alternatives to cancer therapies. However, cell heat sensitivity might be dependent upon cell type. This work focuses on the exposure of Caco-2 cells to hyperthermic temperatures (41-45 °C) and the examination of the mechanisms by which cell death occurs. Caco-2 cells are human colorectal adenocarcinoma cells and were used as model biological tissues. Cells were grown in 96-well plates for one week until confluency was reached. Temperature elevation was achieved by exposing the 96-well plate to the desired temperature by means of hot air in a closed incubator. Cells were exposed to 37, 41 and 45 °C for 30 and 60 minutes. Cell viability was fluorometrically measured immediately and 24 hours after exposure to hyperthermic temperatures. Results demonstrated that an exposure time of 30 minutes is not enough to cause significant cell death. Preliminary results show that when cells are exposed to 41 °C for 60 minutes no significant cell death is observed immediately after exposure to heat, but a ~40% decrease in cell viability can be detected 24 hours after. The same was observed for exposure to 45 °C. These observations indicate that hyperthermia treatment does not cause immediate cell death implying the possibility of an apoptotic cell death mechanism. More hyperthermia analyses, as well as apoptosis assays, will be conducted in order to better understand the cell death mechanism at hyperthermic temperatures. Results will be used as comparative data for magnetic fluid hyperthermia studies.