Phospho β-catenin Serine552 Predicts Recurrence of Non-Functioning Pituitary Tumors After Surgery

NFPTs are tumors without a clinical evidence of hormone hypersecretion. Due to their lack of clinically detectable hormonal activity, they tend to present with mass effects. The molecular pathogenesis of NFPT is not well understood. Treatment of these non-functioning tumors is either surgery or radiotherapy. When recurrent, they are associated with severe morbidity. Characterization of phosphorylation status is critical to elucidate signaling pathways leading to tumorigenesis. Therefore, identifying phosphorylated proteins and their sites of phosphorylation will provide an important clue to the mechanism of NFPT pathogenesis, they can be used as predictor of aggressive behavior as well as activated kinases may be specifically targeted using small molecule inhibitors. Till date no study has undertaken global analysis of phosphoproteins in NFPTs. In this study, we designed an integrative approach involving identification of aberrant phosphorylation events in NFPTs using quantitative (Tandem mass tag-based) mass spectrometry based phosphoproteomic profiling followed by in-silico analysis and validation of candidate phosphoproteins in large cohort of NFPTs.