SPRY2 and neoplasm: Although the stability of the Spry2 protein is enhanced in hypoxia [39], over time the decreased transcription of the SPRY2 gene in hypoxic regions of tumors would be expected to decrease the protein levels of Spry2, diminish “tumor suppressor” actions of Spry2, and reduce the ability of Spry2 to oppose the “tumor promoting” actions of HIF1α/HIF2α.