Zhi-Jiang Wu
and carcinomatous ovarian cells. The apoptosis-related genes p53, bcl-2, and c-
Qi-Rong Gao
myc have important roles in the regulation of programmed cell death, and thus Gang Pei, Ph.D. may be involved in the process of the suspected PROG-induced apoptosis.
METHODS. Antiproliferation effects of PROG on 3AO and AO ovarian carcinoma
Shanghai Institute of Cell Biology, Chinese cells were determined by 3 H-thymidine incorporation. Apoptosis of the PROG-Academy of Sciences, Shanghai, China.
treated cells was determined by DNA laddering analysis and was quantitated by both nuclear condensation and flow cytometry after cells were stained with propidium iodide. Cell cycle analysis was also performed by flow cytometry. The expression of p53, bcl-2, and c-myc after 72 hours of PROG treatment was detected by Northern blot analysis.
RESULTS.
In both 3AO and AO cell lines, cells proliferation was maximally inhibited by PROG after 72 hours of treatment at 10 mM concentration. Under the same conditions, more than 50% of PROG-treated cells had undergone apoptosis, whereas less than 3% of the cells were apoptotic in untreated cell cultures. After exposure to PROG for 72 hours, cells were arrested in the G 1 phase of the cell cycle, and the levels of p53 mRNA were remarkably increased in both cell lines.
No changes in expression of bcl-2 or c-myc were detected.
CONCLUSIONS. PROG significantly inhibited cell proliferation and induced
apoptosis in both of the ovarian carcinoma cell lines tested in this study. PROG treatment markedly up-regulated p53 expression in these cells, indicating involvement of p53 in PROG-induced apoptosis.