We investigated the in vitro effects of
baicalein and
baicalin on human umbilical vein endothelial cells (HUVECs) and on human prostate
tumor cells (DU-145 and PC3) as well as the effect of orally administered
baicalein on the growth of DU-145 cells after
subcutaneous injection into SCID mice. In vitro effects of
baicalein and
baicalin treatment on human
prostate cancer cell lines DU-145 and PC-3 were assessed by employing cell proliferation (MTS) assay, cytotoxicity (LIVE/DEAD) assay, and TUNEL assay. In vitro anti-proliferative and anti-angiogenic properties of
baicalein and
baicalin were studied on HUVECs by sprout assay. The effect of orally administered
baicalein on
tumor growth in SCID mice was studied in four groups (n=10) of animals injected subcutaneously with DU-145 cells and treated daily for 28 days. The control group received only vehicle (
carboxymethylcellulose), whereas the other three groups received escalating doses of
baicalein (10, 20, and 40 mg/kg per day).
Baicalein and
baicalin exhibit dose-dependent growth inhibitory effects on human
prostate cancer cells and umbilical vein endothelial cells in vitro. Also, treatment by these two
flavonoid compounds significantly decreased the average number and length of sprouts formed by the endothelial cell aggregates in a dose-dependent manner. In vivo, treatment of mice with
baicalein demonstrated a statistically significant
tumor volume reduction (p<0.01) when compared to the control. This is the first study demonstrating an in vivo growth inhibitory effect of orally administered
baicalein on human prostate
tumors in mice.