CD44 and cancer: There is evidence that PMCs promote ovarian cancer cell adhesion via interactions between mesothelial cell surface fibronectin and cancer cell-derived α5β1 integrins [101] via the binding of mesothelial hyaluronic acid (HA) with its receptor, CD44, on the cancer cells [102], or via the activity of certain soluble agents released to the environment, e.g., lysophosphatidic acid (LPA) [103].