Mitochondrial Oxidative Phosphorylation Complex Regulates NLRP3 Inflammasome Activation and Predicts Patient Survival in Nasopharyngeal Carcinoma.

Abstract

We previously reported that tumor inflammasomes play a key role in tumor control and act as favorable prognostic markers in nasopharyngeal carcinoma (NPC). Activated inflammasomes frequently form distinguishable specks and govern the cellular secretion of IL-1β. However, we know little about the biological and biochemical differences between cells with and without apoptosis-associated speck-like protein containing a caspase-recruitment domain (ASC) speck formation. In this study, we used proteomic iTRAQ analysis to analyze the proteomes of NPC cells that differ in their ASC speck formation upon cisplatin treatment. We identified proteins that were differentially over-expressed in cells with specks, and found that they fell into two Gene ontology (GO) pathways: mitochondrial oxidative phosphorylation (OxPhos) and ubiquinone metabolism. We observed up-regulation of various components of the OxPhos machinery (including NDUFB3, NDUFB8 and ATP5B), and subsequently found that these changes lead to mitochondrial ROS (mtROS) production, which promotes the formation and activation of NLRP3 inflammasomes and subsequent pyroptosis. In NPC patients, better local recurrence-free survival was significantly associated with high-level expression of NDUFB8 (p = 0.037) and ATP5B (p = 0.029), as examined using immunohistochemistry. However, there were no significant associations between the expression of NDUFB8 and ATP5B with overall survival of NPC patients. Together, our results demonstrate that up-regulated mitochondrial OxPhos components are strongly associated with NLRP3 inflammasome activation in NPC. Our findings further suggest that high-level expression of OxPhos components could be markers for local recurrence and/or promising therapeutic targets in patients with NPC.

• Authors: I-Che Chung, Lih-Chyang Chen, Ngan-Ming Tsang, Wen-Yu Chuang, Tzu-Chieh Liao, Sheng-Ning Yuan, Chun-Nan OuYang, David M Ojcius, Chih-Ching Wu, Yu-Sun Chang
• Journal: Molecular & cellular proteomics : MCP (Mol Cell Proteomics) Vol. 19 Issue 1 Pg. 142-154 (01 2020) ISSN: 1535-9484 [Electronic] United States
• PMID: 31723016 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2020 Chung et al.

Chemical References

• ATP5F1B protein, human
• Biomarkers, Tumor
• Inflammasomes
• NDUFB8 protein, human
• NLR Family, Pyrin Domain-Containing 3 Protein
• NLRP3 protein, human
• Reactive Oxygen Species
• Mitochondrial Proton-Translocating ATPases
• Electron Transport Complex I

Topics

• Adult
• Aged
• Biomarkers, Tumor (genetics, metabolism)
• Cell Line, Tumor
• Disease-Free Survival
• Electron Transport Complex I (genetics, metabolism)
• Female
• Follow-Up Studies
• Humans
• Inflammasomes (metabolism)
• Male
• Middle Aged
• Mitochondria (metabolism)
• Mitochondrial Proton-Translocating ATPases (genetics, metabolism)
• NLR Family, Pyrin Domain-Containing 3 Protein (metabolism)
• Nasopharyngeal Carcinoma (metabolism, mortality, pathology)
• Nasopharyngeal Neoplasms (metabolism, mortality, pathology)
• Oxidative Phosphorylation
• Proteomics (methods)
• RNA Interference
• Reactive Oxygen Species (metabolism)
• Up-Regulation (genetics)