We determined PTEN expression in exosomes from different cancer cell lines i.e. lung carcinoma (A549), breast cancer (MDA-MB-231), colorectal carcinoma (HCT116), and pancreas adenocarcinoma (BxPC-3) (Figure S2, A), to show that PTEN is shed through exosomes from other cancer cell types. This evidence concerns the gene PTEN and breast carcinoma.