scholarly journals Circumventing the Crabtree effect: forcing oxidative phosphorylation (OXPHOS) via galactose medium increases sensitivity of HepG2 cells to the purine derivative kinetin riboside

APOPTOSIS ◽  
2020 ◽  
Vol 25 (11-12) ◽  
pp. 835-852
Author(s):  
Marta Orlicka-Płocka ◽  
Dorota Gurda-Wozna ◽  
Agnieszka Fedoruk-Wyszomirska ◽  
Eliza Wyszko
Keyword(s):  
Oxidative Phosphorylation ◽  
Cancer Cells ◽  
Hepg2 Cells ◽  
Anticancer Agent ◽  
Metabolic Stress ◽  
Crabtree Effect ◽  
Purine Derivative ◽  
Energetic Stress ◽  
Mitochondrial Functions ◽  
Small Molecule Compound

AbstractSmall-molecule compound-based therapies have provided new insights into cancer treatment against mitochondrial impairment. N6-furfuryladenosine (kinetin riboside, KR) is a purine derivative and an anticancer agent that selectively affects the molecular pathways crucial for cell growth and apoptosis by interfering with mitochondrial functions and thus might be a potential mitotoxicant. Metabolism of cancer cells is predominantly based on the Crabtree effect that relies on glucose-induced inhibition of cell respiration and thus on oxidative phosphorylation (OXPHOS), which supports the survival of cancer cells in metabolic stress conditions. The simplest way to circumvent this phenomenon is to replace glucose with galactose in the culture environment. Consequently, cells become more sensitive to mitochondrial perturbations caused by mitotoxicants. In the present study, we evaluated several cellular parameters and investigated the effect of KR on mitochondrial functions in HepG2 cells forced to rely mainly on OXPHOS. We showed that KR in the galactose environment is a more potent apoptosis-inducing agent. KR decreases the mitochondrial membrane potential, reduces glutathione level, depletes cellular ATP, and induces reactive oxygen species (ROS) production in the OXPHOS state, leading to the loss of cell viability. Taken together, these results demonstrate that KR directly acts on the mitochondria to limit their function and that the sensitivity of cells is dependent on their ability to cope with energetic stress.

scholarly journals Potent Anticancer Effect of the Natural Steroidal Saponin Gracillin Is Produced by Inhibiting Glycolysis and Oxidative Phosphorylation-Mediated Bioenergetics

Cancers ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 913 ◽  
Author(s):  
Hye-Young Min ◽  
Honglan Pei ◽  
Seung Yeob Hyun ◽  
Hye-Jin Boo ◽  
Hyun-Ji Jang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Oxidative Phosphorylation ◽  
Cancer Cells ◽  
Anticancer Agent ◽  
Aerobic Glycolysis ◽  
Cancer Cell Line ◽  
Steroidal Saponin ◽  
Antitumor Effects ◽  
Metabolic Switch ◽  
Atp Production

Metabolic rewiring to utilize aerobic glycolysis is a hallmark of cancer. However, recent findings suggest the role of mitochondria in energy generation in cancer cells and the metabolic switch to oxidative phosphorylation (OXPHOS) in response to the blockade of glycolysis. We previously demonstrated that the antitumor effect of gracillin occurs through the inhibition of mitochondrial complex II-mediated energy production. Here, we investigated the potential of gracillin as an anticancer agent targeting both glycolysis and OXPHOS in breast and lung cancer cells. Along with the reduction in adenosine triphosphate (ATP) production, gracillin markedly suppresses the production of several glycolysis-associated metabolites. A docking analysis and enzyme assay suggested phosphoglycerate kinase 1 (PGK1) is a potential target for the antiglycolytic effect of gracillin. Gracillin reduced the viability and colony formation ability of breast cancer cells by inducing apoptosis. Gracillin displayed efficacious antitumor effects in mice bearing breast cancer cell line or breast cancer patient-derived tumor xenografts with no overt changes in body weight. An analysis of publicly available datasets further suggested that PGK1 expression is associated with metastasis status and poor prognosis in patients with breast cancer. These results suggest that gracillin is a natural anticancer agent that inhibits both glycolysis and mitochondria-mediated bioenergetics.

Anticancer Activity of Platinum (II) Complex with 2-Benzoylpyridine by Induction of DNA Damage, S-Phase Arrest, and Apoptosis

2020 ◽  
Vol 20 (4) ◽  
pp. 504-517
Author(s):  
Yu-Lan Li ◽  
Xin-Li Gan ◽  
Rong-Ping Zhu ◽  
Xuehong Wang ◽  
Duan-Fang Liao ◽  
...  
Keyword(s):  
Dna Damage ◽  
B Cell ◽  
Anticancer Activity ◽  
Cancer Cells ◽  
Hepg2 Cells ◽  
Caspase 3 ◽  
Cell Lymphoma ◽  
B Cell Lymphoma ◽  
S Phase ◽  
Caspase 9

Objective: To overcome the disadvantages of cisplatin, numerous platinum (Pt) complexes have been prepared. However, the anticancer activity and mechanism of Pt(II) complexed with 2-benzoylpyridine [Pt(II)- Bpy]: [PtCl2(DMSO)L] (DMSO = dimethyl sulfoxide, L = 2-benzoylpyridine) in cancer cells remain unknown. Methods: Pt(II)-Bpy was synthesized and characterized by spectrum analysis. Its anticancer activity and underlying mechanisms were demonstrated at the cellular, molecular, and in vivo levels. Results: Pt(II)-Bpy inhibited tumor cell growth, especially HepG2 human liver cancer cells, with a halfmaximal inhibitory concentration of 9.8±0.5μM, but with low toxicity in HL-7702 normal liver cells. Pt(II)- Bpy induced DNA damage, which was demonstrated through a marked increase in the expression of cleavedpoly (ADP ribose) polymerase (PARP) and gamma-H2A histone family member X and a decrease in PARP expression. The interaction of Pt(II)-Bpy with DNA at the molecular level was most likely through an intercalation mechanism, which might be evidence of DNA damage. Pt(II)-Bpy initiated cell cycle arrest at the S phase in HepG2 cells. It also caused severe loss of the mitochondrial membrane potential; a decrease in the expression of caspase-9 and caspase-3; an increase in reactive oxygen species levels; the release of cytochrome c and apoptotic protease activation factor; and the activation of caspase-9 and caspase-3 in HepG2 cells, which in turn resulted in apoptosis. Meanwhile, changes in p53 and related proteins were observed including the upregulation of p53, the phosphorylation of p53, p21, B-cell lymphoma-2-associated X protein, and NOXA; and the downregulation of B-cell lymphoma 2. Moreover, Pt(II)-Bpy displayed marked inhibitory effects on tumor growth in the HepG2 nude mouse model. Conclusion: Pt(II)-Bpy is a potential candidate for cancer chemotherapy.

scholarly journals TAMI-57. MEDULLOBLASTOMA UTILIZE GABA TRANSAMINASE TO SURVIVE IN THE CEREBROSPINAL FLUID MICROENVIRONMENT AND PROMOTE LEPTOMENINGEAL DISSEMINATION

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii225-ii226
Author(s):  
Vahan Martirosian ◽  
Krutika Deshpande ◽  
Hao Zhou ◽  
Keyue Shen ◽  
Vazgen Stepanosyan ◽  
...  
Keyword(s):  
Energy Source ◽  
Cerebrospinal Fluid ◽  
Oxidative Phosphorylation ◽  
Cancer Cells ◽  
Metastatic Cancer ◽  
Leptomeningeal Metastases ◽  
Metabolic Phenotype ◽  
Leptomeningeal Disease ◽  
Neural Cells ◽  
Gaba Transaminase

Abstract Medulloblastoma (MB) is a malignant pediatric brain tumor. Studies have shown heterogeneous cells amongst the tumor bulk which mirror normal neural cells in various neurodevelopmental stages. To discern exploited mechanisms promoting MB leptomeningeal disease, we drew conclusions from developmental neurobiology. In normal differentiation, the metabolic phenotype in proliferating neural progenitor cells evolves from a glycolysis-dependent to an oxidative phosphorylation-reliant energetic profile in quiescent differentiated neurons. Cancer cells mirror this evolution, which also grants them the capability to utilize alternative nutrients in the microenvironment as an energy source. Considering metastatic cells are typically in a dormant state and primarily utilize oxidative phosphorylation, we hypothesized metastatic MB cells emulate a quiescent neuron-like cellular profile to survive in the cerebrospinal fluid and form leptomeningeal metastases. To examine this, we query the expression of GABA catabolic enzyme GABA transaminase (ABAT) in MB. GABA is found in the cerebellar and leptomeningeal microenvironments, and is utilized by metastatic cancer cells in the CNS as an energy source. We correlate an increase in ABAT expression with neurodevelopment and show heterogeneous expression of this protein in primary MB tumors. MB cells with increased expression of ABAT were slower-dividing, expressed a genetic and metabolic phenotype reminiscent of quiescent neuron-like cells, and had increased capability to metabolize GABA. Conversely, lower expression of ABAT was associated with an increased proliferation rate and correlated with a progenitor-like cellular profile. Transplantation of MB cells into the leptomeningeal compartment decreased proliferative capacity and enhanced ABAT expression. Xenograft models showed MB cells with ABAT knockdown had increased growth in the cerebellar microenvironment. Conversely, MB cells with ABAT overexpression transplanted into the cerebrospinal fluid formed leptomeningeal metastases whereas ABAT knockdown cells could not. These results suggest ABAT expression in MB cells can be modulated by the tumor microenvironment and is required to form leptomeningeal metastases.

scholarly journals Echinacoside exerts anti-tumor activity via the miR-503-3p/TGF-β1/Smad aixs in liver cancer

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Wen Li ◽  
Jing Zhou ◽  
Yajie Zhang ◽  
Jing Zhang ◽  
Xue Li ◽  
...  
Keyword(s):  
Liver Cancer ◽  
Cancer Cells ◽  
Hepg2 Cells ◽  
Luciferase Reporter ◽  
Therapeutic Effects ◽  
Dependent Manner ◽  
Expression Levels ◽  
Liver Cancer Cells ◽  
Anti Tumor Activity ◽  
Tgf Β1

Abstract Background Echinacoside (ECH) is the main active ingredient of Cistanches Herba, which is known to have therapeutic effects on metastatic tumors. However, the effects of ECH on liver cancer are still unclear. This study was to investigate the effects of ECH on the aggression of liver cancer cells. Methods Two types of liver cancer cells Huh7 and HepG2 were treated with different doses of ECH at different times and gradients. MTT and colony formation assays were used to determine the effects of ECH on the viability of Huh7 and HepG2 cells. Transwell assays and flow cytometry assays were used to detect the effects of ECH treatment on the invasion, migration, apoptosis and cell cycle of Huh7 and HepG2 cells. Western blot analysis was used to detect the effects of ECH on the expression levels of TGF-β1, smad3, smad7, apoptosis-related proteins (Caspase-3, Caspase-8), and Cyto C in liver cancer cells. The relationship between miR-503-3p and TGF-β1 was detected using bioinformatics analysis and Luciferase reporter assay. Results The results showed that ECH inhibited the proliferation, invasion and migration of Huh7 and HepG2 cells in a dose- and time-dependent manner. Moreover, we found that ECH caused Huh7 and HepG2 cell apoptosis by blocking cells in S phase. Furthermore, the expression of miR-503-3p was found to be reduced in liver tumor tissues, but ECH treatment increased the expression of miR-503-3p in Huh7 and HepG2 cells. In addition, we found that TGF-β1 was identified as a potential target of miR-503-3p. ECH promoted the activation of the TGF-β1/Smad signaling pathway and increased the expression levels of Bax/Bcl-2. Moreover, ECH could trigger the release of mitochondrial Cyto C, and cause the reaction Caspases grade. Conclusions This study demonstrates that ECH exerts anti-tumor activity via the miR-503-3p/TGF-β1/Smad aixs in liver cancer, and provides a safe and effective anti-tumor agent for liver cancer.

scholarly journals Oxidative Stress and Apoptotic Responses Elicited by Nostoc-Synthesized Silver Nanoparticles against Different Cancer Cell Lines

Cancers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2099 ◽  
Author(s):  
Reham Samir Hamida ◽  
Gadah Albasher ◽  
Mashael Mohammed Bin-Meferij
Keyword(s):  
Oxidative Stress ◽  
Silver Nanoparticles ◽  
Cancer Cells ◽  
Hepg2 Cells ◽  
Caspase 3 ◽  
Mammalian Target Of Rapamycin ◽  
B Cell Lymphoma ◽  
Phosphorylated Akt ◽  
Hct 116 ◽  
Mcf 7

Green nanoparticles represent a revolution in bionanotechnology, providing opportunities to fight life-threatening diseases, such as cancer, with less risk to the environment and to human health. Here, for the first time, we systematically investigated the anticancer activity and possible mechanism of novel silver nanoparticles (N-SNPs) synthesized by Nostoc Bahar M against the MCF-7 breast cancer cells, HCT-116 colorectal adenocarcinoma cells, and HepG2 liver cancer cells, using cell viability assays, morphological characterization with inverted light and transmission electron microscopy, antioxidants and enzymes (glutathione peroxidase (GPx), glutathione (GSH), adenosine triphosphatase (ATPase), and lactate dehydrogenase (LDH)), and western blotting (protein kinase B (Akt), phosphorylated-Akt (p-Akt), mammalian target of rapamycin (mTOR), B-cell lymphoma 2 (Bcl-2), tumor suppressor (p53), and caspase 3). N-SNPs decreased the viability of MCF-7, HCT-116, and HepG2 cells, with half-maximal inhibitory concentrations of 54, 56, and 80 µg/mL, respectively. They also significantly increased LDH leakage, enhanced oxidative stress via effects on antioxidative markers, and caused metabolic stress by significantly decreasing ATPase levels. N-SNPs caused extensive ultrastructural alterations in cell and nuclear structures, as well as in various organelles. Furthermore, N-SNPs triggered apoptosis via the activation of caspase 3 and p53, and suppressed the mTOR signaling pathway via downregulating apoptosis-evading proteins in MCF-7, HCT-116, and HepG2 cells. Ultrastructural analysis, together with biochemical and molecular analyses, revealed that N-SNPs enhanced apoptosis via the induction of oxidative stress and/or through direct interactions with cellular structures in all tested cells. The cytotoxicity of Nostoc-mediated SNPs represents a new strategy for cancer treatment via targeting various cell death pathways. However, the potential of N-SNPs to be usable and biocompatible anticancer drug will depend on their toxicity against normal cells.

scholarly journals Molecular and Supramolecular Structure of the Mitochondrial Oxidative Phosphorylation System: Implications for Pathology

Life ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 242
Author(s):  
Salvatore Nesci ◽  
Fabiana Trombetti ◽  
Alessandra Pagliarani ◽  
Vittoria Ventrella ◽  
Cristina Algieri ◽  
...  
Keyword(s):  
Oxidative Phosphorylation ◽  
Atp Synthase ◽  
Mitochondrial Permeability Transition ◽  
Ros Generation ◽  
Protonmotive Force ◽  
Mitochondrial Oxidative Phosphorylation ◽  
F1fo Atp Synthase ◽  
Functional Changes ◽  
Age Related ◽  
Mitochondrial Functions

Under aerobic conditions, mitochondrial oxidative phosphorylation (OXPHOS) converts the energy released by nutrient oxidation into ATP, the currency of living organisms. The whole biochemical machinery is hosted by the inner mitochondrial membrane (mtIM) where the protonmotive force built by respiratory complexes, dynamically assembled as super-complexes, allows the F1FO-ATP synthase to make ATP from ADP + Pi. Recently mitochondria emerged not only as cell powerhouses, but also as signaling hubs by way of reactive oxygen species (ROS) production. However, when ROS removal systems and/or OXPHOS constituents are defective, the physiological ROS generation can cause ROS imbalance and oxidative stress, which in turn damages cell components. Moreover, the morphology of mitochondria rules cell fate and the formation of the mitochondrial permeability transition pore in the mtIM, which, most likely with the F1FO-ATP synthase contribution, permeabilizes mitochondria and leads to cell death. As the multiple mitochondrial functions are mutually interconnected, changes in protein composition by mutations or in supercomplex assembly and/or in membrane structures often generate a dysfunctional cascade and lead to life-incompatible diseases or severe syndromes. The known structural/functional changes in mitochondrial proteins and structures, which impact mitochondrial bioenergetics because of an impaired or defective energy transduction system, here reviewed, constitute the main biochemical damage in a variety of genetic and age-related diseases.

scholarly journals AKT but not MYC promotes reactive oxygen species-mediated cell death in oxidative culture

2019 ◽  
Author(s):  
Dongqing Zheng ◽  
Jonathan H. Sussman ◽  
Matthew P. Jeon ◽  
Sydney T. Parrish ◽  
Alireza Delfarah ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Reactive Oxygen Species ◽  
Cell Death ◽  
Oxidative Phosphorylation ◽  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Breast Cancer Cell Lines ◽  
Oxygen Species

ABSTRACTOncogenes can generate metabolic vulnerabilities in cancer cells. Here, we tested how AKT and MYC affect the ability of cells to shift between respiration and glycolysis. Using immortalized mammary epithelial cells, we discovered that constitutively active AKT but not MYC induced cell death in galactose culture, where cells must rely on oxidative phosphorylation for energy generation. However, the negative effects of AKT were short-lived, and AKT-expressing cells recommenced growth after ~15 days in galactose. To identify the mechanisms regulating AKT-mediated cell death, we used metabolomics and found that AKT cells dying in galactose upregulated glutathione metabolism. Next, using proteomics, we discovered that AKT-expressing cells dying in galactose upregulated nonsense-mediated mRNA decay, a marker of sensitivity to oxidative stress. We therefore measured levels of reactive oxygen species (ROS) and discovered that galactose induced ROS in cells expressing AKT but not MYC. Additionally, ROS were required for the galactose-induced death of AKT-expressing cells. We then tested whether these findings could be replicated in breast cancer cell lines with constitutively active AKT signaling. Indeed, we found that galactose induced rapid cell death in breast cancer cell lines and that ROS were required for galactose-induced cell death. Together, our results demonstrate that AKT but not MYC induces a metabolic vulnerability in cancer cells, namely the restricted flexibility to use oxidative phosphorylation.ImplicationsThe discovery that AKT but not MYC restricts the ability to utilize oxidative phosphorylation highlights that therapeutics targeting tumor metabolism must be tailored to the individual genetic profile of tumors.

scholarly journals Sodium citrate inhibits proliferation and induces apoptosis of hepatocellular carcinoma cells

2020 ◽  
Vol 7 (3) ◽  
pp. 3659-3666
Author(s):  
Phuc Hong Vo ◽  
Sinh Truong Nguyen ◽  
Nghia Minh Do ◽  
Kiet Dinh Truong ◽  
Phuc Van Pham
Keyword(s):  
Hepatocellular Carcinoma ◽  
Cancer Cells ◽  
Dna Fragmentation ◽  
Hepg2 Cells ◽  
Annexin V ◽  
Carcinoma Cells ◽  
Human Gastric Cancer ◽  
Apoptosis Pathway ◽  
Hepatocellular Carcinoma Cells ◽  
Activation Assay

Introduction: Cancer cells rely on glycolysis to generate energy and synthesize biomass for cell growth and proliferation (the Warburg effect). Recent studies have shown that citrate has an inhibitory effect on several cancer cells, such as human gastric cancer and ovarian cancer, by inhibiting glycolysis. In this study, we investigated the effects of citrate on the proliferation and apoptosis induction of hepatocellular carcinoma cells. Methods: HepG2 hepatocellular carcinoma cell line was used in this study. The cell proliferation was evaluated by Alamar blue assay. The apoptotic status of the HepG2 cells was recorded by Annexin V/7-AAD assay and caspase 3/7 activation assay. DNA fragmentation was evaluated by nucleus staining assay with Hoechst 33342. Results: The results showed that citrate is able to inhibit the proliferation of HepG2 cells and induce apoptosis in these cells. The initiation time of apoptosis is 4 hours after treatment with 10 mM citrate. Morphology characteristics of DNA fragmentation and broken membranes were also recorded in the apoptotic cells. Conclusion: In conclusion, our study demonstrates that citrate causes HepG2 cell death by the apoptosis pathway.

scholarly journals Effect of Calomelanone, a Dihydrochalcone Analogue, on Human Cancer Apoptosis/Regulated Cell Death in an In Vitro Model

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Wasitta Rachakhom ◽  
Ratana Banjerdpongchai
Keyword(s):  
Cell Death ◽  
Cancer Cells ◽  
Hepg2 Cells ◽  
Cytotoxic Effect ◽  
Human Cancer ◽  
Autophagic Flux ◽  
Dependent Manner ◽  
Anticancer Activities ◽  
Human Cancer Cells ◽  
Regulated Cell Death

Calomelanone, 2 ′ ,6 ′ -dihydroxy-4,4 ′ -dimethoxydihydrochalcone, possesses anticancer activities. This study was conducted to investigate the cytotoxic effect of calomelanone, a dihydrochalcone analogue, on human cancer cells and its associated mechanisms. The cytotoxic effect of calomelanone was measured by MTT assay. Annexin V-FITC/propidium iodide and DiOC6 staining that employed flow cytometry were used to determine the mode of cell death and reduction of mitochondrial transmembrane potential (MTP), respectively. Caspase activities were measured using specific substrates and colorimetric analysis. The expression levels of Bcl-2 family proteins were determined by immunoblotting. Reactive oxygen species were also measured using 2 ′ ,7 ′ -dihydrodichlorofluorescein diacetate and dihydroethidium (fluorescence dyes). Calomelanone was found to be toxic towards various human cancer cells, including acute promyelocytic HL-60 and monocytic leukemic U937 cells, in a dose-dependent manner at 24 h and human hepatocellular HepG2 cells at 48 h. However, the proliferation of HepG2 cells increased at 24 h. Calomelanone was found to induce apoptosis in HL-60 and U937 at 24 h and HepG2 apoptosis at 48 h via the intrinsic pathway by inducing MTP disruption. This compound also induced caspase-3, caspase-8, and caspase-9 activities. Calomelanone upregulated proapoptotic Bax and Bak and downregulated antiapoptotic Bcl-xL proteins in HepG2 cells. Moreover, signaling was also associated with oxidative stress in HepG2 cells. Calomelanone induced autophagy at 24 h of treatment, which was evidenced by staining with monodansylcadaverine (MDC) to represent autophagic flux. This was associated with a decrease of Akt (survival pathway) and an upregulation of Atg5 (the marker of autophagy). Thus, calomelanone induced apoptosis/regulated cell death in HL-60, U937, and HepG2 cells. However, it also induced autophagy in HepG2 depending on duration, dose, and type of cells. Thus, calomelanone could be used as a potential anticancer agent for cancer treatment. Nevertheless, acute and chronic toxicity should be further investigated in animals before conducting investigations in human patients.

scholarly journals Lysimachia christinae Hance as an anticancer agent against breast cancer cells

2020 ◽  
Vol 8 (10) ◽  
pp. 5717-5728
Author(s):  
Hyun A. Kim ◽  
Dong‐Sung Lee ◽  
Hwan Lee ◽  
Joomin Lee
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Breast Cancer Cells ◽  
Anticancer Agent
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