Vascular endothelial cell penetration experiment

The vascular endothelial cell penetration experiment was performed according to the manufacture’s protocol (Glycotech, USA). In brief, the basal cells HUVEC-G2L were cultured on the slides coated with matrigel matrix (BD, USA). The co-cultured reporter cells of SW1990-mcherry and PANC-1-mcherry with corresponding feeder cells (SW1990 and PANC-1, non-treatment or X-ray) were used for the flow cells. The parallel plate flow chamber (Glycotech, USA) was used for flow assay. The flow speed was about 5 ml every hour, and kept for 2 h. 1 day after flow assay, the penetration state was observed by confocal microscope (Leica, TCS SP8, Germany).