[Effect of pingyangmycin on the growth and cell cycle of human vascular endothelial cells].

Objective: To study the effect of pingyangmycin (PYM, bleomycin A5) on the proliferation and cell cycle of the cultured ECV304 cells, a human umbilical vein endothelial cell (HUVEC) line.

Methods: The growth inhibition of PYM on ECV304 cells was measured by MTT assay and the changes in the cell cycle by flow cytometry.

Results: After 10 microg/ml PYM treatment of the cells for 24, 48, and 72 h, the inhibition rates were 44.7%, 59.7%, and 74.4% respectively, showing a dose- and time-dependent inhibitory effect, with the 50% inhibitory concentration (IC50) of PYM corresponding to treatment durations of 24, 48 and 72 h being 32.94, 2.56 and 0.75 microg/ml respectively. Flow cytometry showed that ECV304 cell cycle was arrested at G2-M phase after 24-hour treatment with 1 microg/ml PYM, with significant reduction in the cell ratio of S phase and increase of G2-M phase (P<0.01)

Conclusion: PYM can effectively inhibit the proliferation of ECV304 cells, the mechanism of which might involve the blocking of cell cycle.