title: Apoptotic effect of MG-132 on human tongue squamous cell carcinoma.
abstract: The aim of this study was to investigate the apoptotic effect of a proteasome inhibitor MG-132 on Tca-8113, a cell line of human tongue squamous cell carcinoma. Tca-8113 cells were treated with 10, 20, and 30μM of MG-132, or 5μM thapsigargin. Apoptosis rate was determined with annexin V/propidium iodide double staining. Expression of E3ubiquitin-protein ligase was determined by ELISA, and Grp78 and caspase-12 mRNA, and Grp78 and caspase-12 protein was assessed by RT-PCR and Western blot, respectively. Apoptosis was observed 18h after MG-132 treatment. The apoptotic rate in the 10, 20, and 30μM MG-132 group was 13.5, 19.6 and 34.7%, respectively, which was higher than in the thapsigargin (8.5%, P<0.01) or control group (0.5%, P<0.01). The expression of E3 ubiquitin-protein ligase in the 10, 20, and 30μM MG-132 group was 28.75±2.28, 18.16±0.65, 8.85±0.72, respectively, which was lower than in the thapsigargin (38.96±0.33, P<0.05 or 0.01) or control (40.88±4.52, P<0.05 or 0.01) group. The levels of Grp78 and capase-12 mRNA, Grp78 and caspase-12 protein in the MG-132 groups were higher than in the control group (P<0.01). In conclusion, MG-132 induces apoptosis in Tca-8113 cells in a concentration-dependent manner. The MG-132-induced apoptosis may involve downregulation of E3 ubiquitin ligase, and upregulation of Grp78 and caspase-12.
authors.affiliation: Central Laboratory for Experimental Medicine Liaocheng People's Hospital, Liaocheng and Liaocheng Clinical School of Taishan Medical University, Shandong Province, 252000 China.
authors.forename: Shuang-feng
authors.initials: SF
authors.lastname: Chen
authors.forename: Hai-ying
authors.initials: HY
authors.lastname: Chen
authors.forename: Xian-bin
authors.initials: XB
authors.lastname: Liu
authors.forename: Ying-xin
authors.initials: YX
authors.lastname: Zhang
authors.forename: Wei
authors.initials: W
authors.lastname: Liu
authors.forename: Wei-hua
authors.initials: WH
authors.lastname: Wang
authors.forename: Bin
authors.initials: B
authors.lastname: Zhang
authors.forename: Le-Xin
authors.initials: LX
authors.lastname: Wang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D053454:Caspase 12 / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D000091342:Endoplasmic Reticulum Chaperone BiP; D006360:Heat-Shock Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007976:Leupeptins / Q000494:pharmacology*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D019284:Thapsigargin / Q000494:pharmacology; D014062:Tongue Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics / Q000473:pathology; D044767:Ubiquitin-Protein Ligases / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D015853:Cysteine Proteinase Inhibitors; D000091342:Endoplasmic Reticulum Chaperone BiP; C000717247:HSPA5 protein, human; D006360:Heat-Shock Proteins; D007976:Leupeptins; D012333:RNA, Messenger; D019284:Thapsigargin; D044767:Ubiquitin-Protein Ligases; D053454:Caspase 12; C072553:benzyloxycarbonylleucyl-leucyl-leucine aldehyde