Cells were incubated with CtxB-Alexa647 (652/668 nm-magenta) and rLOX-PP-Atto565 (563/592 nm-red) for 3 hours before imaging. Confocal microscope pictures were formatted in split Z-stacks on the left and merged on the right for each cell line. PWR-1E (A), DU145 (B), PC3 (C), SCC9 (D) and MDA-MD-231(E) cell lines were listed; (DIC), dichromatic image of cells. Various levels of co-localization of rLOX-PP-Atto565 with CTxB-Alexa647 in PWR-1E, PC3, and MDA-MC-231 cell lines confirm that rLOX-PP-Atto565 enters the cell through a caveola-mediated pathway.