PDK1phosphoS135 a potential marker for malignant transformation in human glioma.
The image shows PDK1 S135 phosphorylation (green) detected in grade IV GBM tissue together with adjacent “safety margin of healthy looking tissue” (small square). PDK1phosphoS135 was identified by Bär et al., as a potential tumor promoting marker. The phosphoinositide-dependent kinase 1 (PDK1) is a master kinase regulating cell metabolism and survival. PKCη/Rdx-mediated phosphorylation of PDK1:S135 renders the enzyme independent of growth factor signaling through receptor tyrosine kinase and PI3-kinase. This intracellular loop-back pathway was found to be active in cancer but not in normal cells and tissue.
Image Credit: Séverine Bär