Exosomal levels of miR-99a-5p were up-regulated in the sera of ovarian cancer patients [247], as were other proteins, like L1 cell adhesion molecule (L1CAM), heat stable antigen CD24 (CD24), a disintegrin and metalloproteinase domain-containing protein 10 (ADAM10), extracellular matrix metalloproteinase inducer (EMMPRIN), claudin-4 (CLDN-4), and transforming growth factor beta (TGF-β) [248,249,250]. Here, CLDN4 is linked to ovarian cancer.