The cytotoxic activity of oxysterols, 7β-hydroxycholesterol (7β-OHC) and 25-hydroxycholesterol (25-OHC), has been evaluated using various leukemia cell lines. Among the tested cell lines, both oxysterols showed the highest cytotoxicity to THP-1, human monocytic leukemia cell line. These oxysterols induced apoptosis through down-regulation of Bcl-2 expression and activation of caspases. Also, the oxysterols showed the accumulation at G2/M phase of cell cycle through down-regulation of cyclin B1 expression. Taken together, these results indicated that both 7β-OHC and 25-OHC inhibited the proliferation of THP-1 cells through apoptosis and cell cycle accumulation at G2/M phase.
Bibliographical noteFunding Information:
This work was supported by grants from the Cheju National University Medical Research Fund (2002) and the Ministry of Science and Technology of Korea through the National Research Laboratory Program for Free Radicals.
- Cell cycle