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Enhanced binding capability of nuclear factor-?B with demethylated P2X3 receptor gene contributes to cancer pain in rats.

ABSTRACT: Nuclear factor-kappa B (NF-?B) signaling is implicated in both cancer development and inflammation processes. However, the roles and mechanisms of NF-?B signaling in the development of cancer-induced pain (CIP) remain unknown. This study was designed to investigate the roles of the p65 subunit of NF-?B in regulation of the purinergic receptor (P2X3R) plasticity in dorsal root ganglion (DRG) of CIP rats. We showed here that tumor cell injection produced mechanical and thermal hyperalgesia, and an enhanced body weight-bearing difference, which was correlated with an upregulation of p65 and P2X3R expression in lumber DRGs and a potentiation of ATP-evoked responses of tibia-innervating DRG neurons. Inhibition of NF-?B signaling using p65 inhibitor pyrrolidine dithiocarbamate, BAY-11-7082, or lentiviral-p65 short-hairpin RNA significantly attenuated CIP and reversed the activities of P2X3R. Interestingly, tumor cell injection led to a significant demethylation of CpG island in p2x3r gene promoter and enhanced ability of p65 to bind the promoter of p2x3r gene. Our findings suggest that upregulation of P2X3R expression was mediated by the enhanced binding capability of p65 with demethylated promoter of p2x3r gene, thus contributing to CIP. NF-?Bp65 might be a potential target for treating CIP, a neuropathic pain generated by tumor cell-induced injury to nerves that innervate the skin.

SUBMITTER: Zhou YL

PROVIDER: S-EPMC4770335 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

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Enhanced binding capability of nuclear factor-κB with demethylated P2X3 receptor gene contributes to cancer pain in rats.

Zhou You-Lang YL Jiang Guo-Qin GQ Wei Jinrong J Zhang Hong-Hong HH Chen Wei W Zhu Hongyan H Hu Shufen S Jiang Xinghong X Xu Guang-Yin GY

Pain 20151001 10

Nuclear factor-kappa B (NF-κB) signaling is implicated in both cancer development and inflammation processes. However, the roles and mechanisms of NF-κB signaling in the development of cancer-induced pain (CIP) remain unknown. This study was designed to investigate the roles of the p65 subunit of NF-κB in regulation of the purinergic receptor (P2X3R) plasticity in dorsal root ganglion (DRG) of CIP rats. We showed here that tumor cell injection produced mechanical and thermal hyperalgesia, and an ...[more]

PMID: 26049406

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Dataset Information

Enhanced binding capability of nuclear factor-?B with demethylated P2X3 receptor gene contributes to cancer pain in rats.

Publications

Enhanced binding capability of nuclear factor-κB with demethylated P2X3 receptor gene contributes to cancer pain in rats.

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