Spinal Cord Stimulation Increases Chemoefficacy and Prevents Paclitaxel-Induced Pain via CX3CL1
Eellan Sivanesan, Karla R. Sanchez, Chi Zhang, Shaoqiu He, Bengt Linderoth, Kimberly Stephens, Srinivasa N. Raja, Yun Guan
Abstract
Introduction Despite increasing utilization of spinal cord stimulation (SCS), its effects on chemoefficacy, cancer progression, and chemotherapy-induced peripheral neuropathy (CIPN) pain remain unclear. Up to 30% of adults who are cancer survivors may suffer from CIPN, and there are currently no effective preventative treatments. Materials and Methods Through a combination of bioluminescent imaging, behavioral, biochemical, and immunohistochemical approaches, we investigated the role of SCS and paclitaxel (PTX) on tumor growth and PTX-induced peripheral neuropathy (PIPN) pain development in T-cell–deficient male rats (Crl:NIH-Foxn1rnu) with xenograft human non–small cell lung cancer. We hypothesized that SCS can prevent CIPN pain and enhance chemoefficacy partially by modulating macrophages, fractalkine (CX3CL1), and inflammatory cytokines. Results We show that preemptive SCS enhanced the antitumor efficacy of PTX and prevented PIPN pain. Without SCS, rats with and without tumors developed robust PIPN pain-related mechanical hypersensitivity, but only those with tumors developed cold hypersensitivity, suggesting T-cell dependence for different PIPN pain modalities. SCS increased soluble CX3CL1 and macrophages and decreased neuronal and nonneuronal insoluble CX3CL1 expression and inflammation in dorsal root ganglia. Conclusion Collectively, our findings suggest that preemptive SCS is a promising strategy to increase chemoefficacy and prevent PIPN pain via CX3CL1-macrophage modulation.