title: Interference with HMGB1 increases the sensitivity to chemotherapy drugs by inhibiting HMGB1-mediated cell autophagy and inducing cell apoptosis.
abstract: Non-small cell lung cancer is commonly seen with higher morbidity and mortality. High-mobility group protein 1 (HMGB1) is a highly conserved nuclear protein, which is involved in multiple human diseases including cancers. However, the mechanisms of HMGB1 in non-small cell lung cancer remain unclear. The goal of the present study is to identify the relationship between HMGB1 and the progresssion of non-small cell lung cancer and investigate the molecular mechanism of HMGB1 in non-small lung cancer cell lines. Firstly, we detected the expression levels of HMGB1 by by real-time PCR and western blotting analysis, and the results demonstrated that HMGB1 was much higher expressed in non-small cell lung cancer cell lines, including A549, SPC-1-1, NCI-2170, SK-MES-1, and NCI-H1299, compared with that of WI-38. Next, 5 μM of adriamycin (AMD), 20 μM of cisplatin (DDP), and 50 μM of methotrexate (MTX) were used to treat A549 cells and SPC-A-1 cells for 48 h. The results showed that treatment with chemotherapy drugs significantly increased the levels of HMGB1 in A549 cells and SPC-A-1 cells. Moreover, the expression levels of HMGB1 increased in a time-dependent manner being treated with DDP. Then, the endogenous HMGB1 expression was successfully interferred with shRNA specific to HMGB1 in A549 and SPC-A-1 cells, which was detected by western blotting analysis. Then, the cisplatin-sensitive A549 cells and cisplatin-resistant A549/DDP cells were treated with increasing concentrations of cisplatin for 24, 48, and 72 h; cell viability were analyzed by MTT assay; and IC50 values were calculated. The results demonstrated that the expression level of HMGB1 in A549/DDP cells was much higher than that of A549 cells; moreover, transfection with HMGB1 shRNA in A549/DDP cells decreased the IC50 value of cisplatin in A549/DDP cells. The expression levels of autophagy-related proteins beclin-1 and LC3-II were significantly higher in A549/DDP cells or the A549 cells treated with chemotherapeutic drugs, compared with that in A549 cells. However, interference with endogenous HMGB1 obviously suppressed autophagy-related proteins and increased cell apoptosis rate and the expression of cleaved caspase-3 in A549/DDP cells. All of the data suggested that interference with the endogenous HMGB1 significantly inhibited cell autophagy and increased cell apoptosis of A549/DDP cells. Thus, the study on the resistance of chemotherapy drugs would provide a theoretical reference for clinical treatment of non-small cell lung cancer.
authors.affiliation: Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Ruiguang
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Pathology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Da Dao #1277, Jianghan District, Wuhan, Hubei, 430000, China. liyanhopeful@126.com.
authors.forename: Yan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Zhongliang
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Lingjuan
authors.initials: L
authors.lastname: Chen
authors.affiliation: Cancer Center, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China.
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Dong
authors.affiliation: Department of Pathology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Jiefang Da Dao #1277, Jianghan District, Wuhan, Hubei, 430000, China.
authors.forename: Xiu
authors.initials: X
authors.lastname: Nie
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis; D001343:Autophagy / Q000187:drug effects; D000071186:Beclin-1; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002945:Cisplatin / Q000008:administration & dosage*; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D024243:HMGB1 Protein / Q000096:biosynthesis* / Q000235:genetics; D006801:Humans; D008565:Membrane Proteins / Q000096:biosynthesis; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis
chemical_list: D051017:Apoptosis Regulatory Proteins; C491997:BECN1 protein, human; D000071186:Beclin-1; D024243:HMGB1 Protein; C585491:HMGB1 protein, human; C477012:MAP1LC3A protein, human; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D002945:Cisplatin
keywords: Apoptosis; Autophagy; Chemotherapy drug; High-mobility group protein 1; Non-small cell lung cancer