In vivo, OC (5–10 mg/kg) synergizes with tamoxifen, lowering tumor burden by 97% in BT-474 xenografts through dual ERα degradation and SMYD2 inhibition—the latter blocking ERα methylation at Lys302, a post-translational modification critical for ER stability and chromatin occupancy [133]. The gene discussed is ESR1; the disease is neoplasm.