Impact of temperature on cell death in a cell-culture model of hepatocellular carcinoma.

BACKGROUND Radiofrequency ablation (RFA) is one treatment option for hepatocellular carcinoma (HCC) where tumour cells are destroyed by heat. However, there is lack of knowledge about cellular reactions after heating. Therefore, we studied cell death after heat application in a cell-culture setting mimicking HCC. MATERIALS AND METHODS Intracellularly stained hepatic stellate cells (LX-1) and HCC cells (HepG2) were cultivated in co-culture or alone. Apoptosis was determined by flow cytometry using AnnexinV-PE and eFluor®450. RESULTS Heating resulted in early apoptosis for 20-30% of HepG2 cells and 10-15% of LX-1 cells. Late apoptosis was observed in a large percentage of cells 24 h after heating at 65°C for 15 min or 75°C for 5 min; 65°C for 10 min resulted in a moderate increase and 55°C for 15 min resulted in a minor percentage of late apoptotic cells. CONCLUSION Heat-treated LX-1 and HepG2 cells die by apoptosis. This finding is important for future planning tools to ameliorate RFA outcome in clinic.