The transportation of apoptosis-inducing factor and DNA damage during hydroxycamptothecin-induced apoptosis of SMMC-7721 cells
- Author:
Yu-Rong FU
1
Author Information
1. Faculty of Laboratory Medicine
- Publication Type:Journal Article
- Keywords:
Alkaloids, comptothecin;
Apoptosis;
Apoptosis inducing factor;
Liver neoplasms
- From:
Tumor
2007;27(7):511-514
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To investigate the relationship between transportation of apoptosis-inducing factor (AIF) from mitochondria to nucleus and DNA damage at different time points during apoptosis of SMMC-7721 cells induced by hydroxycamptothecin (HCPT). Methods: Cells were harvested at different time points after HCPT treatment. The mitochondrium, cytosol, and nucleus were isolated with mitochondria isolation kit. These fractions were used for western blot. Transportation of AIF from mitochondrium to the nucleus at different time points was observed by confocal microscopy. At the same time, DNA damage was detected by TUNEL assay. Results: Western blot showed that transportation of AIF from mitochondrium to nucleus was not observed after treatment with HCPT for 1 h. However, AIF immunoreactivity was significantly increased in the nuclear fraction at 6, 12 and 24 h after HCPT treatment. Confocal microscopy demonstrated that AIF was released from mitochondrium at 6 h after HCPT treatment. The massive transportation of AIF to the nucleus occurred at 12 and 24 h after HCPT treatment. At the same time, DNA damage was observed by TUNEL assay. Conclusion: AIF release is one of the early biochemical changes of apoptosis of SMMC-7721 cells after HCPT treatment. The DNA damage occurrs in parallel with AIF translation to nucleus.