Figure 7. Fluorescence microscopy images of the triple-negative breast cancer cell line MDA-MB-231 expressing GFP. The images were taken at different times after treatment with VLP-GOx@HSA. The bubble-like formations are shown with yellow arrows. See the videos in the Supplementary information.
The effect of the treatment with VLP-GOx@HSA on a triple-negative breast cancer cell line (MDA-MB-231) expressing the green fluorescent protein (GFP) was monitored by fluorescence microscopy (Fig. 7 and videos SI). After 1-hour treatment in the presence of nanoreactors, the morphology of cells changed drastically, maybe due to oxidative stress. After 2 hours, bubbles are produced inside the cells suggesting a high production of hydrogen peroxide, and the fluorescence starts to diminish. The bubble production is increasing, and the fluorescence continues to diminish after 3 hours. Finally, after 4 hours the cells are very damaged, and the fluorescence has completely disappeared.