title: MicroRNA-375 sensitizes tumour necrosis factor-alpha (TNF-α)-induced apoptosis in head and neck squamous cell carcinoma in vitro.
abstract: We investigated the effect of microRNA-375 (miR-375) on tumour necrosis factor-alpha (TNF-α)-induced cell death in head and neck squamous cell carcinoma, and further explored the potential molecular mechanism underlying this phenomenon. Cal27 cells were transfected with miR-375 mimic and subsequently treated with or without TNF-α (10 ng/ml). An additional group of cells were treated with TNF-α alone. The resulting morphological changes were observed, and the percentage of sub-G1 cells was measured. The protein expression and cleavage of caspase 3, caspase 8, and poly(ADP ribose) polymerase (PARP) were determined through Western blotting. The results showed a significant increase in cell death in the combination group, but not in the groups treated with miR-375 mimic, TNF-α alone, or control. The data obtained from sub-G1 cells supported the notion that miR-375 increases the accumulation of sub-G1. In the combination group, the degradation of caspase 3, caspase 8, and PARP was observed and the cleavage of these enzymes was detected. The pan-caspase inhibitor, Z-VAD, inhibited the apoptosis of Cal27 cells treated with a combination of miR-375 mimic and TNF-α. In addition, the apoptosis inhibitory proteins, cFLIP-L and cIAP1, were down-regulated in a time-dependent manner. Taken together, these data suggest that miR-375 sensitizes TNF-α-induced apoptosis, and the reduction in the expression of the apoptosis inhibitory proteins cFLIP-L and cIAP2 plays an important role in this sensitization.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Guanghua School of Stomatology, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.forename: H
authors.initials: H
authors.lastname: Huang
authors.forename: C
authors.initials: C
authors.lastname: Wang
authors.forename: X
authors.initials: X
authors.lastname: Liu
authors.forename: F
authors.initials: F
authors.lastname: Hu
authors.forename: M
authors.initials: M
authors.lastname: Liu
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D053446:CASP8 and FADD-Like Apoptosis Regulating Protein / Q000187:drug effects; D002294:Carcinoma, Squamous Cell / Q000473:pathology*; D053148:Caspase 3 / Q000187:drug effects; D053181:Caspase 8 / Q000187:drug effects; D018929:Cell Culture Techniques; D016923:Cell Death / Q000187:drug effects*; D045744:Cell Line, Tumor; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D016193:G1 Phase / Q000187:drug effects; D006258:Head and Neck Neoplasms / Q000473:pathology*; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins / Q000187:drug effects; D035683:MicroRNAs / Q000494:pharmacology*; D016328:NF-kappa B / Q000187:drug effects; D009842:Oligopeptides / Q000494:pharmacology; D011065:Poly(ADP-ribose) Polymerases / Q000187:drug effects; D014162:Transfection; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*
chemical_list: D053446:CASP8 and FADD-Like Apoptosis Regulating Protein; C506386:CFLAR protein, human; D015853:Cysteine Proteinase Inhibitors; D051034:Inhibitor of Apoptosis Proteins; C540933:MIRN375 microRNA, human; D035683:MicroRNAs; D016328:NF-kappa B; D009842:Oligopeptides; D014409:Tumor Necrosis Factor-alpha; C517629:benzyloxycarbonyl-valyl-alanyl-aspartic acid; D011065:Poly(ADP-ribose) Polymerases; C505530:CASP8 protein, human; D053148:Caspase 3; D053181:Caspase 8