Figure 4

Uptake of miR-10b by HMLE cells. A, Exosomal miR-10b was isolated from MDA-MB-231 cells and then added to HMLE cell culture. The control received the exosome-free medium. B, Detection of FAM-miR-10b in the exosome-treated HMLE cells. HMLE cells were co-cultured with MDA-MB-231 cells that had been transfected with FAM-labeled-miR-10b using transwell without direct contact. Twenty-four hours after co-culture, HMLE cells were fixed in 4% paraformaldehyde, and analyzed by fluorescent microscope. Green signals indicate FAM-miR-10b while nuclear counterstaining was performed using propidium iodide (PI). C, The FAM-miR-10b carrying exosomes were first isolated from the same MDA-MB-231 cells that had been transfected with FAM-labeled-miR-10b and then were added to HMLE culture, fixed and visualized by microscopy. FAM-miR-10b signals (green) were spotted around the nucleus similar to what was seen in B.