HLA-A was detected in the EVs from three of the HPV-positive HNSCC lines at higher levels than in EVs from the other HNSCC lines; this might support the use of HLA-A and allelotyping for prognosis in HPV-positive HNSCC, which is currently used in cervical carcinomas and to a lesser extent in HNSCC [53,58,59,60,61,62,63,64,65,66]. Here, HLA-A is linked to head and neck squamous cell carcinoma.