CtBP1–LSD1 complex drives ErbB2 activation via H3K9me2 demethylation in DRGs during paclitaxel-induced neuropathic pain

Paclitaxel (PTX), a commonly utilized chemotherapy drug, is linked to peripheral neuropathy, which limits dosing and significantly affects patients' quality of life. C-terminal binding protein 1 (CtBP1) is a transcriptional coregulator that participates in epigenetic gene regulation, but its role in PTX-induced neuropathic pain remains unclear. In this study, the role of CtBP1 in PTX-induced neuropathic pain is examined, with a focus on its epigenetic regulation in the dorsal root ganglia (DRGs). PTX administration markedly increased CtBP1 protein levels in DRG neurons, which coincided with the development and continuation of mechanical allodynia and thermal hyperalgesia in rat models. Our findings also revealed that CtBP1 interacts with the histone demethylase LSD1-a regulator of H3K9me2-at ErbB2 promoter sites in DRG neurons. PTX treatment increased CtBP1 protein levels, which subsequently induced LSD1 expression and decreased H3K9me2 protein levels at the ErbB2 promoter, indicating epigenetic activation of ErbB2 signaling in DRG neurons implicated in neuropathic pain. Reducing either CtBP1 or LSD1 expression reversed ErbB2 upregulation and attenuated PTX-induced pain sensitivity. These results suggest that the CtBP1-LSD1 complex epigenetically increases ErbB2 expression in DRG neurons, contributing to PTX-induced neuropathy. Targeting the CtBP1-LSD1 pathway could represent a promising therapeutic strategy for the treatment of chemotherapy-induced neuropathic pain.