OSU-ERβ-12

OSU-ERβ-12 is a **novel, highly selective agonist of estrogen receptor beta (ERβ)**, developed to specifically activate the ERβ nuclear hormone receptor with greater than 200-fold selectivity over ERα. Unlike less selective agents, OSU-ERβ-12 robustly activates ERβ, inducing tumor suppressive pathways including apoptosis, cell-cycle arrest, and suppression of cell proliferation in both ovarian and ERα-positive breast cancer cells, including therapy-resistant models. Mechanistically, OSU-ERβ-12 activates ERβ in an orthosteric/ligand-dependent manner, depletes cancer stem cell populations, inhibits epithelial-to-mesenchymal transition (EMT), and blocks ERα transactivity—mechanisms implicated in reducing tumor growth, metastasis, and relapse. Preclinical research also demonstrates anti-inflammatory effects (e.g., lowering pro-inflammatory cytokines in lupus models), and reduction of fibrogenesis in animal models of liver fibrosis. OSU-ERβ-12 was originally synthesized at The Ohio State University by the Drug Development Institute.