Dual-emissive, oxygen-sensing boron nanoparticles quantify oxygen consumption rate in breast cancer cells

Abstract Objectives The F1Fo ATP synthase is a multienzyme complex that produces mitochondrial ATP. Aberrant expression or assembly of F1Fo ATP synthase subunits leads to alterations in energy metabolism. We recently found that breast cancer cells exposed to fluid shear stress (FSS) have significantly enhanced metastatic behavior including chemoresistance and cell proliferation. Chemoresistance depends upon active transport systems, and cell division and growth require ATP. Therefore, we hypothesized that circulating breast cancer cells undergo altered energy metabolism via FSS-induced changes in F1Fo ATP synthase subunits and subsequent mitochondrial remodeling. Methods Non-metastatic MCF7 and metastatic MDA-MB-231 human breast cancer cells were treated with or without FSS and cultured. Cellular proliferation was assayed by measuring cell number and gap distance. Metabolic profile including intracellular ATP and oxygen consumption rate were analyzed. We also quantified abundance of F1Fo ATP synthase subunits using immunoblotting. Results Treatment with FSS significantly increased proliferation of both MCF7 and MDA-MB-231 human breast cancer cells. FSS significantly increased intracellular ATP in MDA-MB-231 breast cancer cells while ATP levels in MCF7 were not significantly changed. MDA-MB-231 cells retained increased ATP after treatment with the uncoupler FCCP, indicating remodeling and decreased reliance on mitochondrial energy metabolism. Interestingly, oxygen consumption rate was significantly increased in both MCF7 and MDA-MB-231 by FSS. We further quantified the abundance of F1Fo ATP synthase subunits in both cell lines. The β- and c-subunits of the F1Fo ATP synthase were significantly depleted in both lines of FSS-treated breast cancer cells. Conclusions Our data show that FSS alters abundance of the F1Fo ATP synthase subunits leading to metabolic remodeling. We suggest that FSS may influence non-metastatic (MCF7) and metastatic cancer cells (MDA-MB-231) differently. Underlying changes in mitochondrial and cytoplasmic ATP production in these cells is still under investigation. However, it is possible that reactive oxygen species generated during FSS may signal a switch to cytoplasmic intracellular energy metabolism. Funding Sources Alabama Life Research Institute Pilot Project (University of Alabama)

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Changes of migration speed of breast cancer cells by oxygen sensing

The Proceedings of the JSME Conference on Frontiers in Bioengineering ◽

10.1299/jsmebiofro.2020.31.2a20 ◽

2020 ◽

Vol 2020.31 (0) ◽

pp. 2A20

Author(s):

Satoshi ARATAKE ◽

Daisuke YOSHINO ◽

Kenichi FUNAMOTO

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Oxygen Sensing ◽

Migration Speed

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Exosomal microRNA-503-3p derived from macrophages represses glycolysis and promotes mitochondrial oxidative phosphorylation in breast cancer cells by elevating DACT2

Cell Death Discovery ◽

10.1038/s41420-021-00492-2 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Shulin Huang ◽

Peizhi Fan ◽

Chaojie Zhang ◽

Jing Xie ◽

Xiaowen Gu ◽

...

Keyword(s):

Breast Cancer ◽

Oxygen Consumption ◽

Oxidative Phosphorylation ◽

Signaling Pathway ◽

Oxygen Consumption Rate ◽

Consumption Rate ◽

Mitochondrial Oxidative Phosphorylation ◽

Atp Level ◽

Glucose Intake ◽

The Impact

AbstractMicroRNAs (miRNAs) are emerging drivers in tumor progression, while the role of miR-503-3p in breast cancer (BC) remains largely unknown. We aimed to explore the impact of macrophage-derived exosomal miR-503-3p in the development of BC by regulating disheveled-associated binding antagonist of beta-catenin 2 (DACT2). miR-503-3p and DACT2 expression in BC tissues and cells was assessed, and the expression of Wnt/β-catenin signaling pathway-related proteins in BC cells was also evaluated. Macrophages were induced and exosomes were extracted. The screened BC cell lines were, respectively, treated with exosomes, miR-503-3p inhibitor/mimic or upregulated/inhibited DACT2, and then the phenotypes, glucose intake, oxygen consumption rate, and adenosine-triphosphate (ATP) level of BC cells were determined. Cell growth in vivo was also observed. MiR-503-3p was elevated, DACT2 was reduced, and Wnt/β-catenin signaling pathway was activated in BC cells. Macrophage-derived exosomes, upregulated miR-503-3p or inhibited DACT2 promoted malignant behaviors of BC cells, glucose intake, and activity of the Wnt/β-catenin signaling pathway, while repressed oxygen consumption rate and ATP level in BC cells. Reversely, reduced miR-503-3p or upregulated DACT2 exerted opposite effects. This study revealed that reduction of macrophage-derived exosomal miR-503-3p repressed glycolysis and promoted mitochondrial oxidative phosphorylation in BC by elevating DACT2 and inactivating Wnt/β-catenin signaling pathway. Our research may provide novel targets for BC treatment.

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Abstract 75: Electron transport chain-dependent oxygen consumption in metastatic breast cancer cells

10.1158/1538-7445.am10-75 ◽

2010 ◽

Cited By ~ 1

Author(s):

Abu-Bakr Al-Mehdi ◽

Mita Patel ◽

Darla Reed

Keyword(s):

Breast Cancer ◽

Oxygen Consumption ◽

Metastatic Breast Cancer ◽

Electron Transport ◽

Cancer Cells ◽

Electron Transport Chain ◽

Breast Cancer Cells ◽

Metastatic Breast ◽

Transport Chain

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Overcoming radiation resistance by iron-platinum metal alloy nanoparticles in human copper transport 1-overexpressing cancer cells via mitochondrial targeting

10.21203/rs.3.rs-63975/v1 ◽

2020 ◽

Author(s):

Tsung-Lin Tsai ◽

Yu-Hsuan Lai ◽

Helen H. W. Chen ◽

Wu-Chou Su

Keyword(s):

Reactive Oxygen Species ◽

Oxygen Consumption ◽

Cancer Cells ◽

Radiation Resistance ◽

Oxygen Consumption Rate ◽

Consumption Rate ◽

Reactive Oxygen ◽

Emission Spectrometry ◽

Oxygen Species ◽

Iron Platinum

Abstract Background Radiation therapy remains an important treatment modality in cancer therapy, however, resistance is a major problem for treatment failure. Elevated expression of glutathione (GSH) is known to associate with radiation resistance. We used GSH overexpressing small cell lung cancer cell lines, SR3A-13 and SR3A-14, established by transfection with γ-glutamylcysteine synthetase (γ-GCS) cDNA, as a model for investigating strategies of overcoming radiation resistance. These radiation-resistant cells exhibit upregulated human copper transporter 1 (hCtr1), which also transports cisplatin. This study was initiated to investigate the effect and the underlying mechanism of iron-platinum nanoparticles (FePt NPs) on radiation sensitization in cancer cells.Methods Uptakes of FePt NPs in these cells were studied by plasma optical emission spectrometry and transmission electron microscopy. Effects of the combination of FePt NPs and ionizing radiation (IR) were investigated by colony formation assay and animal experiment. Intracellular reactive oxygen species (ROS) were assessed by using fluorescent probes and imaged by a fluorescence-activated-cell-sorting caliber flow cytometer. Oxygen consumption rate (OCR) in mitochondria after FePt NP and IR treatment was investigated by a Seahoarse XF24 cell energy metabolism analyzer.Results These hCtr1-overexpressing cells exhibited elevated resistance to IR and the resistance could be overcome by FePt NPs via enhanced uptake of FePt NPs. Overexpression of hCtr1 was responsible for the increased uptake/transport of FePt NPs as demonstrated by using hCtr1-transfected parental SR3A (SR3A-hCtr1-WT) cells. Increased reactive oxygen species (ROS) and drastic mitochondrial damages with substantial reduction of oxygen consumption rate were observed in FePt NPs and IR-treated cells, indicating that structural and functional insults of mitochondria is the lethal mechanism of FePt NPs. Furthermore, FePt NPs also increased the efficacy of radiotherapy in mice bearing SR3A-hCtr1-WT-xenograft tumors.Conclusion These results suggest that FePt NPs can potentially be a novel strategy to improve radiotherapeutic efficacy in hCtr1-overexpressing cancer cells via enhanced uptake and mitochondria targeting.

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Tristetraprolin-mediated hexokinase 2 expression regulation contributes to glycolysis in cancer cells

Molecular Biology of the Cell ◽

10.1091/mbc.e18-09-0606 ◽

2019 ◽

Vol 30 (5) ◽

pp. 542-553 ◽

Cited By ~ 3

Author(s):

Dong Jun Kim ◽

Mai-Tram Vo ◽

Seong Hee Choi ◽

Ji-Heon Lee ◽

So Yeon Jeong ◽

...

Keyword(s):

Oxygen Consumption ◽

Glucose Metabolism ◽

Cancer Cells ◽

Oxygen Consumption Rate ◽

Consumption Rate ◽

Ectopic Expression ◽

Mrna Degradation ◽

Negative Regulator ◽

Extracellular Acidification ◽

Hexokinase 2

Hexokinase 2 (HK2) catalyzes the first step of glycolysis and is up-regulated in cancer cells. The mechanism has not been fully elucidated. Tristetraprolin (TTP) is an AU-rich element (ARE)-binding protein that inhibits the expression of ARE-containing genes by enhancing mRNA degradation. TTP expression is down-regulated in cancer cells. We demonstrated that TTP is critical for down-regulation of HK2 expression in cancer cells. HK2 mRNA contains an ARE within its 3′-UTR. TTP binds to HK2 3′-UTR and enhances degradation of HK2 mRNA. TTP overexpression decreased HK2 expression and suppressed the glycolytic capacity of cancer cells, measured as glucose uptake and production of glucose-6-phosphate, pyruvate, and lactate. TTP overexpression reduced both the extracellular acidification rate (ECAR) and the oxygen consumption rate (OCR) of cancer cells. Ectopic expression of HK2 in cancer cells attenuated the reduction in glycolytic capacity, ECAR, and OCR from TTP. Taken together, these findings suggest that TTP acts as a negative regulator of HK2 expression and glucose metabolism in cancer cells.

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