MTOR and neoplasm: It is also known that in the case that tumor cells do not receive the stimulus mediated by SP (e.g., when using anti-SP antibodies), the number of apoptotic cells increases; the MAPK signaling pathway, the steady state of HER2 and the endothelial growth factor receptor decrease; and the synthesis of cell-cycle-progression/cell-cycle-related proteins (e.g., mammalian target of rapamycin (mTOR)) is inhibited [31,38].