NF-κB is a ubiquitous transcription factor controlling gene expression of a variety of pro-inflammatory mediators, and activation is linked to cancer cell survival.20 Proposed mechanisms for sulforaphane inhibition of NF-κB include interference with an activating kinase IκBα,21 reduced NF-κB upstream signalling,22 or direct interaction with NF-κB p50 subunit.23 Our data shows sulforaphane binds two other NF-κB subunits p65 (RELA, high-confidence in both lines) and p52 (NFKB2, medium- and high-confidence in MCF7 and MDA-MB-231, respectively). This evidence concerns the gene RELA and cancer.