TY - JOUR AB - Osteosarcoma is a common primary malignant tumor of bone, and the poor prognosis and low 5‑year survival rate have not improved for three decades. The present study aimed to study the effect a combination of celastrol and cisplatin on the human osteosarcoma cell line U‑2OS, and to investigate the mechanism by which celastrol/cisplatin induces the apoptosis of osteosarcoma cells. MTT and Annexin V‑FITC/PI assays were used to evaluate the effects of combined celastrol/cisplatin on growth and apoptosis, respectively, in U‑2OS cells. Morphological changes accompanying cell growth inhibition were observed using a fluorescence microscope. Combination index (CI) analysis was used to evaluate the combinatorial effects of celastrol/cisplatin treatment. Western blotting was used to quantify the expression of apoptosis‑associated proteins. It was identified that celastrol/cisplatin inhibited the growth of U‑2OS cells in a dose‑dependent manner. CI analysis revealed that combined celastrol/cisplatin demonstrated a synergistic effect in U‑2OS cells, with CIs ranging from 0.80 to 0.97 at effect levels from IC10 to IC70. In addition, it was observed that celastrol/cisplatin upregulated the expression of Bcl‑associated X protein, cytochrome c, caspase‑3 and C/EBP homologous protein, and downregulated the expression of Bcl‑2, poly(ADP‑ribose) polymerase, 78 kDa glucose‑regulated protein and caspase‑9, whereas the expression of caspase‑8 remained unchanged. To conclude, celastrol/cisplatin induced apoptosis in U‑2OS cells via the mitochondrial and endoplasmic reticulum pathways, particularly in the former. Celastrol/cisplatin therefore exhibits potential as a novel therapeutic combination for the treatment of osteosarcoma. AD - Department of Orthopedics, Fujian Longyan First Hospital, Longyan First Affiliated Hospital of Fujian Medical University, Longyan, Fujian 364000, P.R. China Department of Orthopedics, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China Multidisciplinary Therapy Center of Musculoskeletal Tumors, The First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi 330006, P.R. China Artificial Joint Engineering and Technology Research Center of Jiangxi Province, Nanchang, Jiangxi 330006, P.R. China AU - Wang,Qiang AU - Yu,Xiaolong AU - Li,Fan AU - Lv,Xin AU - Fu,Xiaoxing AU - Gu,Houyun AU - Liu,Hucheng AU - Liu,Jun AU - Dai,Min AU - Zhang,Bin DA - 2019/03/01 DO - 10.3892/ol.2019.10007 EP - 3313 IS - 3 JO - Oncol Lett KW - apoptosis celastrol cisplatin combination osteosarcoma pathway PY - 2019 SN - 1792-1074 1792-1082 SP - 3305 ST - Efficacy of celastrol combined with cisplatin in enhancing the apoptosis of U‑2OS osteosarcoma cells via the mitochondrial and endoplasmic reticulum pathways of apoptosis T2 - Oncology Letters TI - Efficacy of celastrol combined with cisplatin in enhancing the apoptosis of U‑2OS osteosarcoma cells via the mitochondrial and endoplasmic reticulum pathways of apoptosis UR - https://doi.org/10.3892/ol.2019.10007 VL - 17 ER -