title: Radiotherapy Suppresses Bone Cancer Pain through Inhibiting Activation of cAMP Signaling in Rat Dorsal Root Ganglion and Spinal Cord.
abstract: Radiotherapy is one of the major clinical approaches for treatment of bone cancer pain. Activation of cAMP-PKA signaling pathway plays important roles in bone cancer pain. Here, we examined the effects of radiotherapy on bone cancer pain and accompanying abnormal activation of cAMP-PKA signaling. Female Sprague-Dawley rats were used and received tumor cell implantation (TCI) in rat tibia (TCI cancer pain model). Some of the rats that previously received TCI treatment were treated with X-ray radiation (radiotherapy). Thermal hyperalgesia and mechanical allodynia were measured and used for evaluating level of pain caused by TCI treatment. PKA mRNA expression in dorsal root ganglion (DRG) was detected by RT-PCR. Concentrations of cAMP, IL-1β, and TNF-α as well as PKA activity in DRG and the spinal cord were measured by ELISA. The results showed that radiotherapy significantly suppressed TCI-induced thermal hyperalgesia and mechanical allodynia. The level of PKA mRNA in DRG, cAMP concentration and PKA activity in DRG and in the spinal cord, and concentrations of IL-1β and TNF-α in the spinal cord were significantly reduced by radiotherapy. In addition, radiotherapy also reduced TCI-induced bone loss. These findings suggest that radiotherapy may suppress bone cancer pain through inhibition of activation of cAMP-PKA signaling pathway in DRG and the spinal cord.
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China; Department of Anesthesiology, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Guiqin
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Dong
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Xueming
authors.initials: X
authors.lastname: He
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhao
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China; Department of Anesthesiology, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Aixing
authors.initials: A
authors.lastname: Yang
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Rubing
authors.initials: R
authors.lastname: Zhou
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Ma
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Xie
authors.affiliation: Center for Clinical Research and Translational Medicine, Lianyungang Oriental Hospital, Lianyungang, Jiangsu 222042, China; Division of Anesthesiology & Pain Medicine, Key Laboratory of Carcinogenesis and Translational Research, Ministry of Education of China, Beijing Cancer Hospital, Peking University, Beijing 100142, China; Department of Anesthesiology, Beijing Cancer Hospital, Peking University, Beijing 100142, China.
authors.forename: Xue-Jun
authors.initials: XJ
authors.lastname: Song
mesh_terms: D000818:Animals; D001859:Bone Neoplasms / Q000532:radiotherapy*; D000072716:Cancer Pain / Q000532:radiotherapy*; D005260:Female; D005727:Ganglia, Spinal / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000528:radiation effects; D013116:Spinal Cord / Q000378:metabolism*