The activities of adenosine monophosphate-activated kinase (AMPK), ErbB, mammalian target of rapamycin (mTOR), phosphoinositide 3-kinase (PI3K)-Akt, tumor necrosis factor (TNF), or vascular endothelial growth factor (VEGF) signaling pathways are involved with the development and maintenance processes of various types of pathological pain, and their functional modulation might relieve neuropathic, nociceptive, and bone cancer pain [144, 149, 150, 155, 156, 187–226]. Here, MTOR is linked to bone cancer.