Antognelli C, Palumbo I, Aristei C, Talesa VN. Glyoxalase I inhibition induces apoptosis in irradiated MCF-7 cells via a novel mechanism involving Hsp27, p53 and NF-κB.
Br J Cancer 2014;
111:395-406. [PMID:
24918814 PMCID:
PMC4102940 DOI:
10.1038/bjc.2014.280]
[Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 04/24/2014] [Accepted: 04/30/2014] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND
Glyoxalase I (GI) is a cellular defence enzyme involved in the detoxification of methylglyoxal (MG), a cytotoxic byproduct of glycolysis, and MG-derived advanced glycation end products (AGEs). Argpyrimidine (AP), one of the major AGEs coming from MG modifications of proteins arginines, is a pro-apoptotic agent. Radiotherapy is an important modality widely used in cancer treatment. Exposure of cells to ionising radiation (IR) results in a number of complex biological responses, including apoptosis. The present study was aimed at investigating whether, and through which mechanism, GI was involved in IR-induced apoptosis.
METHODS
Apoptosis, by TUNEL assay, transcript and protein levels or enzymatic activity, by RT-PCR, western blot and spectrophotometric methods, respectively, were evaluated in irradiated MCF-7 breast cancer cells, also in experiments with appropriate inhibitors or using small interfering RNA.
RESULTS
Ionising radiation induced a dramatic reactive oxygen species (ROS)-mediated inhibition of GI, leading to AP-modified Hsp27 protein accumulation that, in a mechanism involving p53 and NF-κB, triggered an apoptotic mitochondrial pathway. Inhibition of GI occurred at both functional and transcriptional levels, the latter occurring via ERK1/2 MAPK and ERα modulation.
CONCLUSIONS
Glyoxalase I is involved in the IR-induced MCF-7 cell mitochondrial apoptotic pathway via a novel mechanism involving Hsp27, p53 and NF-κB.
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