Vinik et al. [165] performed proteomic analysis of small EV and identified seven proteins, fibronectin, focal adhesion kinase 1 (FAK), dual-specificity mitogen-activated protein kinase kinase 1, β-Actin, p90RSK_pT573, N-cadherin, and proto-oncogene c-RAF, to discriminate breast cancer patients from healthy individuals (sensitivity: 94%, specificity: 82%), in which FAK and fibronectin revealed high early diagnostic accuracy. This evidence concerns the gene PTK2 and breast cancer.