MAPK3 and renal cell carcinoma: As emerging studies show that KISS1R activates a series of signaling molecules such as protein kinase C (PKC), extra-cellular signal-regulated kinases 1 and 2 (ERK1/2), p38, and phosphatidylinositol-3-kinase (PI3K) (50), further studies are in progress to investigate the specific mechanism of honokiol, which may have the potential for use as a natural agent against RCC metastasis.