Molecular Pathways Involved in the Pathogenesis and Behavior of Mesenchymal Phosphaturic Tumors Causing Oncogenic Osteomalacia

The tumors that cause oncogenic osteomalacia (TIO) express and release in the circulation phosphaturic factors such as fibroblast growth factor-23 (FGF-23) that decrease renal phosphate absorption through acting in the proximal renal tubule and decreasing Type 2a and 2c sodium-phosphate co-transporter. They typically follow a benign clinical course and even in the rare malignant cases, local recurrence occurs in less than 5% and distant metastasis are very uncommon. In this study we aim to investigate the role of other molecular pathways such as ERK1, ERK2, mTOR, EGFR, MEK1, MEK2, VEGFR3, AKT1, AKT2, IGFR-1, IGFR-2, PDGFRA, PDGFRB, cMET, FGFR2, apart from FGF23, KLOTHO and PHEX, in the behavior of histopathologically benign mesenchymal phosphaturic tumors.