Coenzyme Q Depletion Reshapes MCF-7 Cells Metabolism

Mitochondrial dysfunction plays a significant role in the metabolic flexibility of cancer cells. This study aimed to investigate the metabolic alterations due to Coenzyme Q depletion in MCF-7 cells. Method: The Coenzyme Q depletion was induced by competitively inhibiting with 4-nitrobenzoate the coq2 enzyme, which catalyzes one of the final reactions in the biosynthetic pathway of CoQ. The bioenergetic and metabolic characteristics of control and coenzyme Q depleted cells were investigated using polarographic and spectroscopic assays. The effect of CoQ depletion on cell growth was analyzed in different metabolic conditions. Results: we showed that cancer cells could cope from energetic and oxidative stress due to mitochondrial dysfunction by reshaping their metabolism. In CoQ depleted cells, the glycolysis was upregulated together with increased glucose consumption, overexpression of GLUT1 and GLUT3, as well as activation of pyruvate kinase (PK). Moreover, the lactate secretion rate was reduced, suggesting that the pyruvate flux was redirected, toward anabolic pathways. Finally, we found a different expression pattern in enzymes involved in glutamine metabolism, and TCA cycle in CoQ depleted cells in comparison to controls. Conclusion: This work elucidated the metabolic alterations in CoQ-depleted cells and provided an insightful understanding of cancer metabolism targeting.

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A Critical Role of Glutamine and Asparagine γ-Nitrogen in Nucleotide Biosynthesis in Cancer Cells Hijacked by an Oncogenic Virus

mBio ◽

10.1128/mbio.01179-17 ◽

2017 ◽

Vol 8 (4) ◽

Cited By ~ 19

Author(s):

Ying Zhu ◽

Tingting Li ◽

Suzane Ramos da Silva ◽

Jae-Jin Lee ◽

Chun Lu ◽

...

Keyword(s):

Cell Proliferation ◽

Cancer Cells ◽

Metabolic Pathway ◽

Tca Cycle ◽

Glutamine Metabolism ◽

Transformed Cells ◽

Oncogenic Virus ◽

Phosphoribosyl Pyrophosphate ◽

Rate Limiting

ABSTRACT While glutamine is a nonessential amino acid that can be synthesized from glucose, some cancer cells primarily depend on glutamine for their growth, proliferation, and survival. Numerous types of cancer also depend on asparagine for cell proliferation. The underlying mechanisms of the glutamine and asparagine requirement in cancer cells in different contexts remain unclear. In this study, we show that the oncogenic virus Kaposi’s sarcoma-associated herpesvirus (KSHV) accelerates the glutamine metabolism of glucose-independent proliferation of cancer cells by upregulating the expression of numerous critical enzymes, including glutaminase 2 (GLS2), glutamate dehydrogenase 1 (GLUD1), and glutamic-oxaloacetic transaminase 2 (GOT2), to support cell proliferation. Surprisingly, cell crisis is rescued only completely by supplementation with asparagine but minimally by supplementation with α-ketoglutarate, aspartate, or glutamate upon glutamine deprivation, implying an essential role of γ-nitrogen in glutamine and asparagine for cell proliferation. Specifically, glutamine and asparagine provide the critical γ-nitrogen for purine and pyrimidine biosynthesis, as knockdown of four rate-limiting enzymes in the pathways, including carbamoylphosphate synthetase 2 (CAD), phosphoribosyl pyrophosphate amidotransferase (PPAT), and phosphoribosyl pyrophosphate synthetases 1 and 2 (PRPS1 and PRPS2, respectively), suppresses cell proliferation. These findings indicate that glutamine and asparagine are shunted to the biosynthesis of nucleotides and nonessential amino acids from the tricarboxylic acid (TCA) cycle to support the anabolic proliferation of KSHV-transformed cells. Our results illustrate a novel mechanism by which an oncogenic virus hijacks a metabolic pathway for cell proliferation and imply potential therapeutic applications in specific types of cancer that depend on this pathway. IMPORTANCE We have previously found that Kaposi’s sarcoma-associated herpesvirus (KSHV) can efficiently infect and transform primary mesenchymal stem cells; however, the metabolic pathways supporting the anabolic proliferation of KSHV-transformed cells remain unknown. Glutamine and asparagine are essential for supporting the growth, proliferation, and survival of some cancer cells. In this study, we have found that KSHV accelerates glutamine metabolism by upregulating numerous critical metabolic enzymes. Unlike most cancer cells that primarily utilize glutamine and asparagine to replenish the TCA cycle, KSHV-transformed cells depend on glutamine and asparagine for providing γ-nitrogen for purine and pyrimidine biosynthesis. We identified four rate-limiting enzymes in this pathway that are essential for the proliferation of KSHV-transformed cells. Our results demonstrate a novel mechanism by which an oncogenic virus hijacks a metabolic pathway for cell proliferation and imply potential therapeutic applications in specific types of cancer that depend on this pathway.

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The Cytotoxic Properties of Baeckea frutescens Branches Extracts in Eliminating Breast Cancer Cells

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2019/9607590 ◽

2019 ◽

Vol 2019 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

S. H. Shahruzaman ◽

M. F. Mustafa ◽

S. Ramli ◽

S. Maniam ◽

S. Fakurazi ◽

...

Keyword(s):

Breast Cancer ◽

Glucose Uptake ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Glucose Consumption ◽

Uptake Assay ◽

Glucose Uptake Assay ◽

Baeckea Frutescens ◽

Mcf 7

Breast cancer is the leading cause of cancer death in women in over 100 countries worldwide and accounts for almost 1 in 4 cancer cases among women. Baeckea frutescens of the family Myrtaceae has been used in traditional medicine and is known to possess antibacterial, antipyretic, and cytoprotective properties. In this study, we investigated the role of Baeckea frutescens branches extracts against human breast cancer cells. Baeckea frutescens branches extracts were prepared using Soxhlet apparatus with solvents of different polarity. The selective cytotoxic activity and the glucose consumption rate of Baeckea frutescens branches extracts of various concentrations (20 to 160 ug/ml) at 24-, 48-, and 72-hour time points were studied using MTT and glucose uptake assay. The IC50 values in human breast cancer (MCF-7 and MDA-MB-231) and mammary breast (MCF10A) cell lines were determined. Apoptotic study using AO/PI double staining was performed using fluorescent microscopy. The glucose uptake was measured using 2-NBDG, a fluorescent glucose analogue. The phytochemical screening of major secondary metabolites in plants was performed. This study reports that Baeckea frutescens branches extracts showed potent selective cytotoxic activity against MCF-7 cells compared to MDA-MB-231 cells after 72 hours of treatment. Evidence of early apoptosis which includes membrane blebbing and chromatin condensation was observed after 72 hours of treatment with Baeckea frutescens branches extracts. Interestingly, for the glucose uptake assay, the inhibition was observed as early as 24 hours upon treatment. All Baeckea frutescens extracts showed the presence of major secondary metabolites such as tannin, triterpenoid, flavonoid, and phenol. However, alkaloid level was unable to be determined. The identification of Baeckea frutescens and its possible role in selectively inhibiting glucose consumption in breast cancer cells defines a new role of natural product that can be utilised as an effective agent that regulates metabolic reprogramming in breast cancer.

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Contribution by different fuels and metabolic pathways to the total ATP turnover of proliferating MCF-7 breast cancer cells

Biochemical Journal ◽

10.1042/bj3640309 ◽

2002 ◽

Vol 364 (1) ◽

pp. 309-315 ◽

Cited By ~ 161

Author(s):

Michael GUPPY ◽

Peter LEEDMAN ◽

XinLin ZU ◽

Victoria RUSSELL

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Cancer Metabolism ◽

Aerobic Glycolysis ◽

Cancer Cell Line ◽

Cell Types ◽

Atp Production ◽

Atp Turnover ◽

Innovative System ◽

Mcf 7

For the past 70 years the dominant perception of cancer metabolism has been that it is fuelled mainly by glucose (via aerobic glycolysis) and glutamine. Consequently, investigations into the diagnosis, treatment and the basic metabolism of cancer cells have been directed by this perception. However, the data on cancer metabolism are equivocal, and in this study we have sought to clarify the issue. Using an innovative system we have measured the total ATP turnover of the MCF-7 breast cancer cell line, the contributions to this turnover by oxidative and glycolytic ATP production and the contributions to the oxidative component by glucose, lactate, glutamine, palmitate and oleate. The total ATP turnover over approx. 5days was 26.8μmol of ATP·107 cells−1·h−1. ATP production was 80% oxidative and 20% glycolytic. Contributions to the oxidative component were approx. 10% glucose, 14% glutamine, 7% palmitate, 4% oleate and 65% from unidentified sources. The contribution by glucose (glycolysis and oxidation) to total ATP turnover was 28.8%, glutamine contributed 10.7% and glucose and glutamine combined contributed 40%. Glucose and glutamine are significant fuels, but they account for less than half of the total ATP turnover. The contribution of aerobic glycolysis is not different from that in a variety of other non-transformed cell types.

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Breast Cancer Diagnosed by MRI Using Mesoporous TiO2-Coated (Fe3O4) Nanoparticles

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.18437 ◽

2020 ◽

Vol 20 (10) ◽

pp. 6561-6567 ◽

Cited By ~ 1

Author(s):

Bo Zheng ◽

Minghua Xue ◽

Xinyi Zhang ◽

Ning Tian ◽

Dongmei Wang

Keyword(s):

Breast Cancer ◽

Glucose Metabolism ◽

Cancer Cells ◽

Mammary Epithelial Cells ◽

Glucose Consumption ◽

Mammary Epithelial ◽

Blue Staining ◽

Human Mammary Epithelial ◽

Significant Uptake ◽

Mcf 7

Objective: This study aimed to determine the effects of dimer captosuccinic acid-coated Fe3O4 (super paramagnetic) nanoparticles (NP) on 2-deoxy-d-glucose in targeted cancer cells with high rates of glucose metabolism. Methods: We prepared Fe3O4@DMSA NP and 2-DG-conjugated Fe3O4@DMSA NP, γ-FE, O, and @DMSA-DG NP. Glucose consumption in MDA-MB-231 and MCF-7 breast cancer cells was determined using γ-Fe2O3@DMSA NP or Fe3O4@DMSA-DG NP, and absorption was tested using Prussian blue staining, ultraviolet colorimetry, and magnetic resonance imaging. Results: Glucose consumption was the highest in MDA-MB-231, and the lowest in human mammary epithelial cells (HMEPiC). The significant uptake of Fe2O3@DMSA-DG NP by MDA-MB-231 and MCF-7 cells within two hours was inhibited by glucose. The uptake of Fe3O4@DMSA-DG NP was significantly higher in MDA-MB-231 than in MCF-7 cells, whereas Fe3O4@DMSA NP was not obviously uptaken by either cell line. Absorption was also not evident in HMEPiC incubated with Fe3O4@DMSA-DG NP and Fe3O4@DMSA NP. Conclusions: The tumor targeting efficacy of 2-DG coated Fe3O4@DMSA NP was improved over Fe3O4,@DMSA NP in cancer cells with high rates of glucose metabolism.

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The Involvement of PPARs in the Peculiar Energetic Metabolism of Tumor Cells

10.20944/preprints201805.0034.v1 ◽

2018 ◽

Author(s):

Andrea Antonosante ◽

Michele d'Angelo ◽

Vanessa Castelli ◽

Mariano Catanesi ◽

Dalila Iannotta ◽

...

Keyword(s):

Fatty Acid ◽

Cancer Cells ◽

Fatty Acid Synthesis ◽

Cancer Metabolism ◽

Cholesterol Metabolism ◽

Aerobic Glycolysis ◽

Acid Synthesis ◽

Energetic Metabolism ◽

Metabolic Alterations ◽

Long Time

Energy homeostasis is crucial for cell fate since all cellular activities are strongly dependent on the balance between catabolic and anabolic pathways. In particular, metabolic and energetic modulation has been reported in cancer cells long time ago, but have been neglected for a long time. Instead, during the past 20 years a recovery of the study of cancer metabolism has led to better consider metabolic alterations in tumors. Cancer cells must adapt their metabolism to meet the energetic and biosynthetic demands that accompany rapid growth of the primary tumor and colonization of distinct metastatic sites. They are largely dependent on aerobic glycolysis for their energy production and also are associated with increased fatty acid synthesis and increased rates of glutamine utilization. Emerging evidence has shown that therapeutic resistance to cancer treatment may arise due to deregulation in glucose metabolism, fatty acid synthesis, and glutamine utilization. Cancer cells exhibit a series of metabolic alterations induced by mutations leading to gain-of-function of oncogenes and loss-of-function of tumor suppressor genes that include increased glucose consumption, reduced mitochondrial respiration, increased reactive oxygen species generation and cell death resistance, all of which responsible for cancer progression. Cholesterol metabolism is also altered in cancer cells and supports uncontrolled cell growth. In this context, we review the roles of PPARs transcription factors, master regulators of cellular energetic metabolism, in the control and deregulation of energetic homeostasis observed in cancer. We highlight the different contribution of the different PPAR isotypes in different cancers and the differential control of their transcription in the different cancer cells.

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Metformin Treatment or PRODH/POX-Knock Out Similarly Induces Apoptosis by Reprograming of Amino Acid Metabolism, TCA, Urea Cycle and Pentose Phosphate Pathway in MCF-7 Breast Cancer Cells

Biomolecules ◽

10.3390/biom11121888 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1888

Author(s):

Thi Yen Ly Huynh ◽

Ilona Oscilowska ◽

Jorge Sáiz ◽

Magdalena Nizioł ◽

Weronika Baszanowska ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Pentose Phosphate Pathway ◽

Breast Cancer Cells ◽

Pentose Phosphate ◽

Glutamine Metabolism ◽

Metabolic Effects ◽

Knock Out ◽

Drastic Increase ◽

Mcf 7

It has been considered that proline dehydrogenase/proline oxidase (PRODH/POX) is involved in antineoplastic activity of metformin (MET). The aim of this study is identification of key metabolites of glycolysis, pentose phosphate pathway (PPP), tricarboxylic acids (TCA), urea cycles (UC) and some amino acids in MET-treated MCF-7 cells and PRODH/POX-knocked out MCF-7 (MCF-7crPOX) cells. MCF-7crPOX cells were generated by using CRISPR-Cas9. Targeted metabolomics was performed by LC-MS/MS/QqQ. Expression of pro-apoptotic proteins was evaluated by Western blot. In the absence of glutamine, MET treatment or PRODH/POX-knock out of MCF-7 cells contributed to similar inhibition of glycolysis (drastic increase in intracellular glucose and pyruvate) and increase in the utilization of phospho-enol-pyruvic acid, glucose-6-phosphate and some metabolites of TCA and UC, contributing to apoptosis. However, in the presence of glutamine, MET treatment or PRODH/POX-knock out of MCF-7 cells contributed to utilization of some studied metabolites (except glucose), facilitating pro-survival phenotype of MCF-7 cells in these conditions. It suggests that MET treatment or PRODH/POX-knock out induce similar metabolic effects (glucose starvation) and glycolysis is tightly linked to glutamine metabolism in MCF-7 breast cancer cells. The data provide insight into mechanism of anticancer activity of MET as an approach to further studies on experimental breast cancer therapy.

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Biogenic metal nanoformulations induce Bax/Bcl2 and caspase mediated mitochondrial dysfunction in human breast cancer cells (MCF 7)

RSC Advances ◽

10.1039/c4ra11686k ◽

2015 ◽

Vol 5 (3) ◽

pp. 2159-2166 ◽

Cited By ~ 22

Author(s):

Murugaraj Jeyaraj ◽

Arun Renganathan ◽

Gnanasekar Sathishkumar ◽

Andy Ganapathi ◽

Kumpati Premkumar

Keyword(s):

Breast Cancer ◽

Mitochondrial Dysfunction ◽

Cancer Cells ◽

Human Breast Cancer ◽

Breast Cancer Cells ◽

Human Breast Cancer Cells ◽

Human Breast ◽

Caspase Cascade ◽

Mcf 7

Green synthesized metal NPs can potentially inhibit the proliferation of MCF-7 cells and trigger apoptosis through Bax/Bcl2 and caspase–cascade mediated mitochondrial dysfunction.

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AMPK maintains TCA cycle through sequential phosphorylation of PDHA to promote tumor metastasis

Cell Stress ◽

10.15698/cst2020.12.238 ◽

2020 ◽

Vol 4 (12) ◽

pp. 273-277

Author(s):

Zhen Cai ◽

Danni Peng ◽

Hui-Kuan Lin

Keyword(s):

Oxidative Stress ◽

Cancer Cells ◽

Lung Metastasis ◽

Cancer Metabolism ◽

Cancer Metastasis ◽

Pyruvate Dehydrogenase Complex ◽

Tca Cycle ◽

Pyruvate Metabolism ◽

Primary Tumors ◽

And Oxidative Stress

Cancer represents the leading public health problem throughout the world. Globally, about one out of six deaths is related to cancer, which is largely due to the metastatic lesions. However, there are no effective strategies for targeting cancer metastasis. Identification of the key druggable targets maintaining metastasis is crucial for cancer treatment. In our recent study (Cai et al. (2020), Mol Cell, doi: 10.1016/j.molcel.2020.09.018), we found that activity of AMPK was enriched in metastatic tumors compared to primary tumors. Depletion of AMPK rendered cancer cells more sensitive to metabolic and oxidative stress, leading to the impairment of breast cancer lung metastasis. Activation of AMPK rewired cancer metabolism towards TCA cycle, which protects disseminated cancer cells from both metabolic and oxidative stress-induced cell death, and facilitates cancer metastasis. Further, AMPK critically maintained the activity of pyruvate dehydrogenase complex (PDH), the rate limiting enzyme involved in TCA cycle, thus favoring the pyruvate metabolism towards TCA cycle rather than converting it to lactate. Mechanistically, AMPK was shown to co-localize with PDHA, the catalytic subunit of PDH, in the mitochondrial matrix and directly triggered the phosphorylation of PDHA on Ser295 and Ser314. Hyper-phosphorylation of Ser295 and Ser314 of PDHA promotes lung metastasis through elevating activity of PDH. Of note, PDHA Ser314 phosphorylation abrogated the interaction between PDHA and PDHKs leading to the dephosphorylation on previously reported S293 site, whose phosphorylation serves as a negative signal for PDH activation, while S295 phosphorylation serves as an intrinsic catalytic site required for pyruvate metabolism. Our study presented the first evidence for the pro-metastatic property of the AMPK-PDH axis and advance our current understanding of how PDH is activated under physiological and pathological conditions.

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CBMT-01. ALANINE FUELS ENERGY METABOLISM OF GLIOBLASTOMA CELLS

Neuro-Oncology ◽

10.1093/neuonc/noz175.123 ◽

2019 ◽

Vol 21 (Supplement_6) ◽

pp. vi32-vi33

Author(s):

Omkar Ijare ◽

David Baskin ◽

Kumar Pichumani

Keyword(s):

Energy Metabolism ◽

Cancer Cells ◽

Cancer Metabolism ◽

Treatment Options ◽

Unmet Need ◽

Tca Cycle ◽

Essential Amino Acids ◽

Acetyl Coa ◽

Pancreatic Cancer Cells ◽

Thaw Cycle

Abstract Despite available aggressive treatment options, glioblastoma multiforme (GBM) has a median survival of 16 months indicating an urgent unmet need to develop new therapeutic strategies. Earlier, we have demonstrated that both glucose and acetate are the two major nutrients leading to synthesis of approximately ~60% acetyl-CoA in the brain tumors. Therefore, there must be other nutrients that may contribute to bioenergetic needs of highly proliferative GBM cells. Alanine is one of the non-essential amino acids (NEAA) that is constantly produced in cancer cells through Warburg glycolysis and its role in cancer metabolism is not well understood. Recently, it has been shown that alanine produced by pancreatic stellar cells contributed to the energy metabolism in pancreatic cancer cells. However, it is not known whether GBM can use alanine as an energy source. Here, we test whether GBM cells have the ability to metabolize alanine as a fuel to meet its increased energy requirements. Patient-derived GBM cells were cultured with 2.0 mM [3-13C]alanine for the final 24 hours, harvested in 50% methanol, snap-frozen in liquid N2, freeze-thaw cycle 3 times and lysates were stored at -80 °C. Derivatized material from the frozen lysates were used for GC-MS analysis to determine carbon mass isotopomer distribution (MID) of various glycolytic and TCA cycle intermediates. Our results indicated that [3-13C]alanine entered the GBM cells and produced [3-13C]lactate via pyruvate. Also, alanine-derived [3-13C]pyruvate led to the generation of [2-13C]acetyl-CoA, which entered TCA cycle and produced M+1 13C isotopomers of citrate, glutamate, malate and aspartate. MID showed the following 13C enrichment (M+1) values: citrate, 6.9 % ± 0.3%; glutamate, 4.4% ± 0.3%; malate, 2.1% ± 0.6%; 2.1% ± 0.5%. This preliminary data shows that GBM cells are capable of utilizing alanine to generate energy and produce precursors for biomolecular synthesis.

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New Insights into the Mechanisms Used by Inhibitors Targeting Glutamine Metabolism in Cancer Cells

10.1101/2021.09.20.461106 ◽

2021 ◽

Author(s):

Shawn K Milano ◽

Qingqiu Huang ◽

Thuy-Tien T Nguyen ◽

Sekar Ramachandran ◽

Aaron Finke ◽

...

Keyword(s):

Cancer Cells ◽

Drug Target ◽

Rational Design ◽

Tca Cycle ◽

Glutamine Metabolism ◽

Allosteric Inhibitors ◽

Inhibitor Binding ◽

Drug Candidates ◽

The Tca Cycle ◽

Potent Drug

Many cancer cells become dependent on glutamine metabolism to compensate for glycolysis being uncoupled from the TCA cycle. The mitochondrial enzyme Glutaminase C (GAC) satisfies this "glutamine addiction" by catalyzing the first step in glutamine metabolism, making it an attractive drug target. Despite one of the allosteric inhibitors (CB-839) being in clinical trials, none of the drugs targeting GAC are approved for cancer treatment and their mechanism of action is not well understood. A major challenge has been the rational design of better drug candidates: standard cryo-cooled X-ray crystal structures of GAC bound to CB-839 and its analogs fail to explain their potency differences. Here, we address this problem by using an emerging technique, serial room temperature crystallography, which enabled us to observe clear differences between the binding conformations of inhibitors with significantly different potencies. A computational model was developed to further elucidate the molecular basis of inhibitor potency. We then corroborated the results from our modeling efforts by using recently established fluorescence assays that directly read-out inhibitor binding to GAC. Together, these findings provide new insights into the mechanisms used by a major class of allosteric GAC inhibitors and for the future rational design of more potent drug candidates.

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