Search

Ultraviolet (UV) radiation is considered to be a potent cell-damaging agent in various cell lineages; however, the effect of UV light-emitting diode (LED) irradiation on human cells remains unclear. The aim of the present study was to examine the effect of UV LED irradiation emitting at 280 nm on cultured HL-60 human leukemia cells, and to explore the underlying mechanisms. HL-60 cells were irradiated with UV LED (8, 15, 30 and 60 J/m2) and incubated for 2 h after irradiation. The rates of cell proliferation and apoptosis, the cell cycle profiles and the mRNA expression of B-cell lymphoma 2 (Bcl-2) were detected using cell counting kit-8, multicaspase assays, propidium iodide staining and reverse transcription-quantitative polymerase chain reaction, respectively. The results showed that UV LED irradiation (8-60 J/m2) inhibited the proliferation of HL-60 cells in a dose-dependent manner. UV LED at 8-30 J/m2 induced dose-dependent apoptosis and G0/G1 cell cycle arrest, and inhibited the expression of Bcl-2 mRNA, while UV LED at 60 J/m2 induced necrosis. In conclusion, 280 nm UV LED irradiation inhibits proliferation and induces apoptosis and necrosis in cultured HL-60 cells. In addition, the cell cycle arrest at the G0/G1 phase and the downregulation of Bcl-2 mRNA expression were shown to be involved in UV LED-induced apoptosis. [ABSTRACT FROM AUTHOR]

The aim of the current study was to investigate the biological effect on T24 cells and human umbilical vein endothelial cells (HUVECs) of transfection with brain-specific angiogenesis inhibitor-1 (BAI-1). The recombinant plasmid pReceiver-M61-BAI-1 was transfected into human superficial bladder tumor cells (T24) and HUVECs, in parallel with the vector control. mRNA and protein expression levels of BAI-1 were then detected by quantitative polymerase chain reaction (qPCR) and western blotting, respectively. Cell apoptosis of T24 cells and HUVECs prior and subsequent to transfection with BAI-1 was analyzed by flow cytometric analysis. Proliferation of T24 cells and HUVECs prior and subsequent to transfection of BAI-1 was assessed by the MTT method. T24 cells and HUVECs transfected with pReceiver-M61-BA1-1 were classed as the experimental group; T24 cells and HUVECs transfected with p-Receiver-M61 were the control group. qPCR and western blotting methods confirmed that there was positive expression of BAI-1 in T24 cells and HUVECs transfected with pReceiver-M61-BAI-1, however BAI-1 was not expressed in T24 cells and HUVECs transfected with pReceiver-M61. The results of the MTT assay demonstrated that absorbance was markedly reduced in HUVECs at 12, 48 and 72 h subsequent to transfection with pReceiver-M61-BAI-1 when compared with that of the control group and in T24 cells transfected with p-Receiver-M61-BAI-1. Furthermore, flow cytometry results also indicated that the apoptotic rate of HUVECs transfected with p-Receiver-M61-BAI-1 was significantly increased compared with that of the control group and T24 cells transfected with p-Receiver-M61-BAI-1. BAI-1 was observed to markedly inhibit the proliferation of vascular endothelial cells in vitro, however, no direct inhibition by BAI-1 was observed in T24 cells. In conclusion, BAI-1 is suggested to be a potential novel therapautic target for the inhibition of tumor neovascularization. [ABSTRACT FROM AUTHOR]