Determination of Cell Death Induced by Lovastatin on Human Colon Cell Line HT29 Using the Comet Assay

BACKGROUND: Apoptosis or programmed cell death is an essential process for elimination of damaged cells. Also, induction of apoptosis is fundamental for treating cancer. Screening for agents that induce apoptosis in tumor cells help in the development of novel agents for cancer treatment. Numerous studies suggest that the exposure of tumor cells to statins can lead to cell death via two separate processes: apoptosis or necrosis. Severe fragmentation of DNA during apoptosis can be readily measured by the neutral comet assay. Migration of DNA fragments of apoptotic cells by the electrical field can produce comet-like images. OBJECTIVES: The aim of this study was to determine the type of cell death induced by lovastatin on human colon tumor cells by using the neutral comet assay and to evaluate the utility of this method for detection of apoptosis. MATERIALS AND METHODS: HT29 cells were grown in DMEM medium then exposed to different concentrations of lovastatin, and DNA fragmentation associated with apoptosis was detected by the neutral comet assay method. RESULTS: Lovastatin induced an apoptotic response in the HT29 cell line and produced a comet pattern similar to the positive control. CONCLUSIONS: This study showed that lovastatin can induce apoptosis in the HT29 cell line and confirmed the utility of comet assay for detection of apoptosis.