Expression of Leptin Receptor and Effects of Leptin on Papillary Thyroid Carcinoma Cells

Background. Obesity has been hypothesized to contribute to the aggressiveness of thyroid cancer through the production of abnormal levels of serum adipokines. Leptin receptor (OB-R) expression has also been documented in papillary thyroid cancer (PTC). Aim. In this translational study, we analyzed in vitro the effects of leptin on the growth and migration of thyroid cancer cells (TPC-1 and K1), the molecular mechanisms underlying leptin's action, and the influence of prolonged leptin exposure on cell response to a protein kinase inhibitor lenvatinib. The expression levels of OB-R mRNA and protein were also investigated in vivo in a series of aggressive PTCs divided into two groups based on the presence of the BRAF mutation. Results. In TPC-1 and K1 cells, prolonged treatment with leptin (500ng/ml for 96h) resulted in a mild increase in the proliferation (about 20% over control only in K1 cells, p