MTOR and gastric cancer: Agents targeting molecules such as the epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) receptor, P13k/Akt/mTor pathway, insulin-like growth factor receptor (IGFR), c-Met pathways, fibroblast growth factor receptor (FGFR) and other pathways are promising candidates for targeted therapy for GC and are now in clinical development.