Rubratoxin B induces apoptosis in human hepatoma cells

Abstract

The possibility that rubratoxin B induces apoptosis in hepatoma cells was investigated. Exposure to rubratoxin B caused the shrinkage of HuH-7 cells, and this effect was dosedependent. In 40 μg/ml rubratoxin B-treated HepG2 and HuH-7 cells, we observed condensation of chromatin and the presence of dense spherical structures in the nuclei, showing that rubratoxin B induces apoptosis in hepatoma cells. DNA fragmentation detected by modified TdT-mediated dUTP nick end labeling (TUNEL) method was also increased in a dosedependent manner in HepG2 cells, and a similar trend was observed in HuH-7 cells. These results indicated that rubratoxin B-induced apoptosis in HepG2 and HuH-7 cells is accompanied by DNA fragmentation.