Osteosarcoma (OS) is the most common malignant bone tumor in children and adolescents. Histone acetyltransferases (HATs), such as p300, CBP and PCAF, modulate numerous biological processes, including cellular proliferation and oncogenesis, through histone acetylation. In the present study, it was investigated whether the curcumin analogs such as pentagamavunon‑1 (PGV‑1) and chemoprevention curcumin analog‑1.1 (CCA‑1.1) could target p300 and suppress OS. Computational analysis indicated that PGV‑1 and CCA‑1.1 bind to the HAT domain of p300. Accordingly, these analogs efficiently inhibited the HAT activity of p300