대한대장항문학회

Purpose: This study was undertaken to reveal the molecular mechanism underlying sulindac-induced apoptosis in the human colon cancer cell line HT-29 (mutant p53). Methods: Apoptosis was determined by using Hoechst 33342 staining, and translocation of proteins was established by using immunofluorescence, immunoelectron microscopy, and Western blotting after ultra- fractionation. Results: This type of apoptosis was associated with decreased mitochondrial membrane potential, a translocation of the apoptosis-inducing factor (AIF) to the nucleus, and morphological evidence of nuclear condensation. However, DNA electrophoresis did not elucidate the ladder pattern of DNA fragments. Instead, a pulse-field gel electrophoresis showed that sulindac led to disintegration of nuclear DNA into-high- molecular-weight DNA fragments of about 100∼300 kbp. Conclusions: Our findings indicate that sulindac induces large-scale DNA fragmentation, suggesting a predominantly AIF-mediated cell-death process, through translocation of the AIF to the nucleus in HT-29 cells. J Korean Soc Coloproctol 2004;20:191-198