Furthermore, NGF has been shown to regulate insulin signaling and combat insulin resistance by enhancing glucose uptake, particularly in degenerating neurons, while TrkA can transactivate the insulin receptor (IR) signaling pathway and the oncogenic fusion protein Trk-T1, originating from thyroid carcinoma, can trigger the formation of the IRS–Growth factor receptor-bound protein 2 (IRS-Grb2) complex with the related pro-oncogenic processes (transformation of fibroblasts and intestinal epithelial cells). Here, GRB2 is linked to thyroid gland carcinoma.