The cells viability were inhibited with DPN treatment compared with that in control (E2 vs. E2 + DPN; E2 vs. E2 + DPN + water; P < 0.001), while the inhibited cells viability were reversed with 3-MA treatment (E2 + DPN + 3-MA vs. E2 + DPN; E2 + DPN + 3-MA vs. E2 + DPN + water; P < 0.001), indicating that ERβ could inhibit the osteosarcoma cells viability probably through inducing autophagy (Fig. 1). The gene discussed is ESR2; the disease is osteosarcoma.