<p>Proteasome inhibition by bortezomib or <i>PSMA1</i> knockdown results in an increase in IκBα, which in turn decreases NF-κB binding to the promoters of FA/HR genes including <i>FANCD2</i> and <i>BRCA1</i>. This reduces the availability of these DNA repair proteins for recruitment to DNA damage sites, resulting in decreased RAD51 focus formation and HR following induction of DNA double strand breaks by ionizing radiation.</p
