title: Silencing of Barkor/ATG14 sensitizes osteosarcoma cells to cisplatin‑induced apoptosis.
abstract: Although surgical excision following neoadjuvant chemotherapy has contributed to the long-term survival of osteosarcoma patients, patients that do not respond to commonly used drugs including cisplatin, have a poor prognosis. Autophagy is important in the inhibition of chemotherapeutic apoptosis. Therefore, we investigated whether knockdown of Beclin1-associated autophagy-related key regulator (Barkor/ATG14) promoted cisplatin-induced apoptosis in a drug-resistant osteosarcoma cell line in vitro. Saos-2 cells were transfected with Barkor siRNA. Sensitivity of the Barkor siRNA-transfected cell line to cisplatin was evaluated. Silencing of Barkor did not directly inhibit the growth rate of the transfected cells, but it significantly increased their sensitivity to cisplatin. The results of flow cytometry and 4',6-diamidino-2-phenylindole (DAPI) staining revealed that Barkor siRNA-transfected Saos-2 cells treated with cisplatin exhibited much higher rates of apoptosis than the control and control siRNA-transfected cells. Additionally, the combination of silencing of Barkor with cisplatin treatment promoted the expression of caspase-12 and calpain. The increase of cisplatin cytotoxicity may therefore be involved in endoplasmic reticulum (ER) stress-associated apoptosis. Bcl-2 was markedly downregulated in dose‑dependent cisplatin‑treated Barkor-transfected-Saos-2 cells. Findings of the present study suggest that the combination of silencing of Barkor and cisplatin enhanced the antitumor efficacy through the Barkor‑related ER- and mitochondrial-mediated apoptotic pathway.
authors: Department of Orthopedic Surgery, The 117th Hospital of People's Liberation Army, Hangzhou, Zhejiang, P.R. China.
authors: Zhifang
authors: Z
authors: Zhao
authors: Department of Orthopedic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, P.R. China.
authors: Lijiang
authors: L
authors: Tao
authors: Department of Orthopedic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, P.R. China.
authors: Chengchun
authors: C
authors: Shen
authors: Department of Orthopedic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, P.R. China.
authors: Bing
authors: B
authors: Liu
authors: Department of Orthopedic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, P.R. China.
authors: Zhengming
authors: Z
authors: Yang
authors: Department of Orthopedic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, P.R. China.
authors: Huimin
authors: H
authors: Tao
mesh_terms: D033942:Adaptor Proteins, Vesicular Transport / Q000235:genetics* / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects*; D001343:Autophagy / Q000187:drug effects; D000071183:Autophagy-Related Proteins; D053454:Caspase 12 / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D002945:Cisplatin / Q000494:pharmacology*; D015536:Down-Regulation; D019008:Drug Resistance, Neoplasm; D059865:Endoplasmic Reticulum Stress / Q000187:drug effects; D020868:Gene Silencing; D006801:Humans; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D012516:Osteosarcoma / Q000235:genetics*; D034741:RNA, Small Interfering / Q000235:genetics; D014162:Transfection; D015854:Up-Regulation; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: C539000:ATG14 protein, human; D033942:Adaptor Proteins, Vesicular Transport; D000071183:Autophagy-Related Proteins; C494826:BAX protein, human; D034741:RNA, Small Interfering; D051028:bcl-2-Associated X Protein; C506444:CASP12 protein, human; D053454:Caspase 12; D002945:Cisplatin