Exosomes provide a noninvasive, quantitative method to assess PTEN status in PC patients.

<p>This figure provides a comparison study of PTEN assessment using exosomal PTEN, and Immunohistochemistry of PC patient tumors. Immunohistochemistry of tumor tissues from four PC patients demonstrates the heterogeneity of PTEN expression in prostate tumors. A. Eosin & hematoxylin staining. B. Staining with secondary antibodies. C. Staining with PTEN specific antibodies, arrows indicate PTEN positive cells. D. Assessment of PTEN expression using plasma exosomes from the same patients. E) A scanning electron microscope micrograph showing the homogenous population of exosomes collected from the patient blood. Exosomes were attached to a cover slip using polylysine, and processed for scanning electron microscopy.