Fig. 1

Supernatant of ROR1/2-overexpressing MCF-7 cells is sufficient to transfer receptors to originally ROR-negative cells. A Western blot: Expression of ROR1 and ROR2 in breast cancer cells. B Western blot: Expression of ROR1 and ROR2 in MDA-MB-231 and 4T1 CRISPR control (Cr-CTL) or ROR1 KO (Cr-ROR1) cells or MCF-7 cells stably overexpressing either an empty vector (pCMV, pcDNA) or ROR1/ROR2 overexpression construct (pROR1/pROR2). C Immunofluorescence: Localization of ROR1 or ROR2 in MCF-7 pROR1 or pROR2, respectively, was imaged by confocal microscopy. D ROR-negative MCF-7 wildtype (WT) cells were stimulated with supernatant (SN) of pROR1 or pROR2 cells and ROR1/2 signals were visualized by immunofluorescence and confocal microscopy. To generate EV-free SN, the SN was centrifuged for 2 h at 143,000 × g. Scale bar: 10 µm