Peritoneal MCs isolated from peritoneal lavage fluids displayed high CD44 expression, substantial mesothelial-to-mesenchymal transition (MMT) and released EVs that both directed tumor invasion and caused reprogramming of secretory profiles by increasing TGF-β1 and uPA/uPAR expression and MMP-2/9 activation in tumor cells. The gene discussed is CD44; the disease is neoplasm.