Objective: TO investigate the anti-angiogenic effects of Pien Tze Huang (片仔癀, PZH) in vivo and in vitro. Me.otis: Human umbilical vein endothelial cells (HUVECs) were treated with 0 mg/mL, 0.25 mg/mL, 0.5 mg/mL, and 1 mg/mL of PZH for 24 h, 48 h and 72 h, respectively. Chicken embryo chorioallantoic membrane (CAM) model was used to evaluate in vivo angiogenesis. An ECMatrix gel system was used to evaluate in vitro angiogenesis by examining the tube formation of HUVECs. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed to determine HUVEC viability. Cell density of HUVECs was observed by phase- contrast microscopy. HUVEC migration was determined by wound healing method. The mRNA and protein expression of vascular endothelial growth factor A (VEGF-A) and basic fibroblast growth factor (bFGF) in both HUVEC and human colon adenocaminoma cells (HT-29) was examined by reverse transcription polymerase chain reaction (RT-PCR) and enzyme linked immune sorbent assay (ELISA), respectively. Results: PZH treatment significantly reduced the total number of blood vessels compared with the untreated control in the chicken embryos and resulted in a significant decrease in capillary tube formation and cell density of HUVECs (P〈0.05). In addition, treatment with 0.25-1 mg/mL of PZH for 24 h, 48 h, and 72 h respectively reduced cell viability by 9%-52%, 24%-87% or 25%-87%, compared with the untreated control cells (P〈0.05). Moreover, PZH treatment decreased the migration of HUVECs. Furthermore, PZH close-dependently suppressed the expression of VEGF-A and bFGF on both mRNA and protein levels (P〈0.05). Conclusion: PZH could inhibit angiogenesis in vivo in CAM model and in vitro on HUVECs, suggesting that inhibiting tumor angiogenesis might be one of the mechanisms by which PZH treats cancer.
Objective:To investigate the cellular effects of Pien Tze Huang(片仔癀,PZH) in the HT-29 human colon carcinoma cell line.Methods:The viability of HT-29 cells was determined by MTT assay.A fluorescence-activated cell sorting(FACS) analysis with annexin-V/propidium iodide(PI) and JC-1 staining were performed to determine cell apoptosis and the loss of mitochondrial membrane potential,respectively.Activation of caspase 3 was evaluated by a colorimetric assay.The mRNA expression levels of Bcl-2 and Bax were measured by reverse transcription polymerase chain reaction(RT-PCR).Results:PZH,in a dose- and time-dependent manner,reduced viability and induced apoptosis of HT-29 cells.Moreover,PZH treatment resulted in the collapse of the mitochondrial membrane potential,activation of caspase 3,and an increase in the Bax/Bcl-2 ratio.Conclusion:PZH inhibits the growth of HT-29 cells by inducing cancer cell apoptosis via regulation of the Bcl-2 family and activation of caspase 3,which may,in part,explain its anticancer activity.