PLXNB2 and breast cancer: However, subsequent immunoblotting analysis revealed a truncated form of PLXNB2 (also known as β subunit42) in breast cancer cell-derived EVs which did not contain the full-length protein (Supplementary Fig. S1e), therefore the PLXNB2 functions in EVs were not further investigated and we focused on characterizing its cellular functions instead in this study.