Inhibition of nuclear factor-κB and target genes during combined therapy with proteasome inhibitor bortezomib and reirradiation in patients with recurrent head-and-neck squamous cell carcinoma

Conclusions: In combination with reirradiation, the maximally tolerated dose of bortezomib was exceeded at a dose of 0.6 mg/m2 and the threshold of proteasome inhibition. Although this regimen with reirradiation is not feasible, bortezomib induced detectable differences in NF-κB localization, apoptosis, and NF-κB-modulated genes and cytokines in tumor and serum in association with tumor reduction, indicating that other schedules of bortezomib combined with primary radiotherapy or reirradiation may merit future investigation.