Inhibition of the neuronal NFκB pathway attenuates bortezomib-induced neuropathy in a mouse model

Bortezomib is a proteasome inhibitor with a remarkable antitumor activity, used in the clinic as first line treatment for multiple myeloma. One hallmark of bortezomib mechanism of action in neoplastic cells is the inhibition of nuclear factor kappa B (NFκB), a transcription factor involved in cell survival and proliferation. Bortezomib-induced peripheral neuropathy is a dose-limiting toxicity that often requires adjustment of treatment and affects patient's prognosis and quality of life. Since disruption of NFκB pathway can also affect neuronal survival, we assessed the role of NFκB in bortezomib-induced neuropathy by using a transgenic mouse that selectively provides blockage of the NFκB pathway in neurons. Interestingly, we observed that animals with impaired NFκB activation developed significantly less severe neuropathy than wild type animals, with particular preservation of large myelinated fibers, thus suggesting that neuronal NFκB activation plays a positive role in bortezomib induced neuropathy and that bortezomib treatment might induce neuropathy by inhibiting NFκΒ in non-neuronal cell types or by targeting other signaling pathways. Therefore, inhibition of NFκB might be a promising strategy for the cotreatment of cancer and neuropathy.