FOS and Pain: In cancer-induced bone pain DRG and dorsal horn neurons show increased expression of c-FOS and dynorphin, together with markedly hypertrophic spinal astrocytes and upregulation of galanin and activating transcription factor 3 (ATF3), considered as markers of DRG nerve damage, but no increase on substance P and CGRP has been reported, differently from inflammatory and neuropathic pain [159,160].