GDNF and prostate carcinoma: The fact that GDNF is up-regulated in prostate tumor stroma in various settings and given the well-established function of GDNF as a trophic factor in multiple different tissues types, we hypothesized that GDNF secretion by the TME upon DNA damage could actively influence prostate cancer cellular responses and/or growth properties, and thereby modify their sensitivity to cytotoxic, cytostatic or pathway-directed therapeutics.