Surface proteins programmed cell death–protein1 (PD-1) and programmed death–ligand 1 (PD-L1) on EVs, alongwith PD-1 and PD-L1 mRNA cargo within EVs, were detected with SiEVresolution, surpassing the sensitivities achieved by conventionalBuEV analysis methods. Proteins likecarcinoembryonic antigen (CEA) and PD-L1 are specific to lung adenocarcinoma,a type of NSCLC, and are linked to either the presence of tumors orthe evasion of the immune system., Another potentialprotein biomarker is EGFR, frequently found in high levels or withmutations in lung cancer cells. Here, CD274 is linked to lung cancer.