HDAC9 and cancer: The differences we observed in LXR activity between subtypes expand on previous observations that NR cofactors could usefully serve as therapeutic biomarkers, which are targetable through epigenetic drugs (e.g., HDAC inhibitors that impair their epigenetic transcription silencing targets and that are recruited by NCOR1 and NCOR2) aimed at reinstating pre-cancer gene expression patterns and responsiveness.