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Kostritskaia Y, Klüssendorf M, Pan YE, Hassani Nia F, Kostova S, Stauber T. Physiological Functions of the Volume-Regulated Anion Channel VRAC/LRRC8 and the Proton-Activated Chloride Channel ASOR/TMEM206. Handb Exp Pharmacol 2024; 283:181-218. [PMID: 37468723 DOI: 10.1007/164_2023_673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
Volume-regulated anion channels (VRACs) and the acid-sensitive outwardly rectifying anion channel (ASOR) mediate flux of chloride and small organic anions. Although known for a long time, they were only recently identified at the molecular level. VRACs are heteromers consisting of LRRC8 proteins A to E. Combining the essential LRRC8A with different LRRC8 paralogues changes key properties of VRAC such as conductance or substrate selectivity, which is how VRACs are involved in multiple physiological functions including regulatory volume decrease, cell proliferation and migration, cell death, purinergic signalling, fat and glucose metabolism, insulin signalling, and spermiogenesis. VRACs are also involved in pathological conditions, such as the neurotoxic release of glutamate and aspartate. Certain VRACs are also permeable to larger, organic anions, including antibiotics and anti-cancer drugs, making them an interesting therapeutic target. ASOR, also named proton-activated chloride channel (PAC), is formed by TMEM206 homotrimers on the plasma membrane and on endosomal compartments where it mediates chloride flux in response to extracytosolic acidification and plays a role in the shrinking and maturation of macropinosomes. ASOR has been shown to underlie neuronal swelling which causes cell death after stroke as well as promoting the metastasis of certain cancers, making them intriguing therapeutic targets as well.
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Affiliation(s)
- Yulia Kostritskaia
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Malte Klüssendorf
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Yingzhou Edward Pan
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Fatemeh Hassani Nia
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Simona Kostova
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany
| | - Tobias Stauber
- Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany.
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2
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Koriem KMM, Abdeen AMA. Shikimic acid recovers diarrhea and its complications in SD rats fed lactose diet to induce diarrhea. Lab Anim Res 2023; 39:28. [PMID: 37950334 PMCID: PMC10636980 DOI: 10.1186/s42826-023-00179-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 10/27/2023] [Accepted: 11/03/2023] [Indexed: 11/12/2023] Open
Abstract
BACKGROUND Diarrhea is the increase of excretion of human water content and an imbalance in the physiologic processes of the small and large intestine while shikimic acid is an important biochemical metabolite in plants. This study aims to study the anti-diarrheal activity of shikimic acid through restoring kidney function, antioxidant activity, inflammatory markers, sodium/potassium-ATPase activity, apoptosis genes, and histology of the kidney in SD rats fed lactose diet to induce diarrhea. RESULTS Thirty-six male SD rats (150 ± 10 g, 12 weeks old) were divided into 2 equal groups (18 rats/group) as follows: normal and diarrheal rats. Normal rats were divided into 3 equal groups of 6 rats each: the control, shikimic acid, and desmopressin drug groups. Diarrheal rats were also divided into 3 equal groups of 6 rats each: diarrheal, diarrheal rats + shikimic acid, and diarrheal rats + desmopressin drug groups. Shikimic acid restored serum urea and creatinine, urinary volume, kidney weight, sodium, potassium, and chloride balance in serum and urine. The acid returned the antioxidant (superoxide dismutase, glutathione peroxidase, catalase, malondialdehyde, NADPH oxidase activity, conjugated dienes, and oxidative index) activity and the inflammatory markers (tumor necrosis factor-α, interleukin-1β, interleukin-6, and interleukin-10) to values approaching the control values. Shikimic acid also restored the sodium/potassium-ATPase activity, the apoptosis genes p53 and bcl-2, and the histology of kidney tissue in diarrheal rats to be near the control group. CONCLUSIONS Shikimic acid rescues diarrhea and its complications through restoring kidney function, serum and urinary electrolytes, antioxidant activity, inflammatory markers, sodium/potassium-ATPase activity, the apoptosis genes, and the histology of the kidney in diarrheal rats to approach the control one.
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Affiliation(s)
- Khaled M M Koriem
- Department of Medical Physiology, Medical Research and Clinical Institute, National Research Centre, 33 El-Buhouth Street, Dokki, P.O. Box 12622, Giza, Egypt.
| | - Alaa M A Abdeen
- Department of Pathology, Faculty of Veterinary Medicine, Cairo University, P.O. Box 12211, Giza, Egypt
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3
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Zhang W, Takahashi S, Shimada N, Maruyama A. 2D-3D-Convertible, pH-Responsive Lipid Nanosheets. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2301219. [PMID: 37376845 DOI: 10.1002/smll.202301219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2023] [Revised: 06/10/2023] [Indexed: 06/29/2023]
Abstract
2D nanosheets self-assembled with amphiphilic molecules are promising tools for biomedical applications; yet, there are challenges to form and stabilize these nanosheets under complex physiological conditions. Here, the development of lipid nanosheets with high structural stability that can be reversibly converted to cell-sized vesicles by changes in pH within the physiological range robustly, are described. The system is controlled by the membrane disruptive peptide E5 and a cationic copolymer anchored on lipid membranes. It is envisioned that nanosheets formed using the dual anchoring peptide/cationic copolymer system can be employed in dynamic lipidic nanodevices, such as the vesosomes described here, drug delivery systems, and artificial cells.
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Affiliation(s)
- Wancheng Zhang
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 B-57 Nagatsuta, Midori-ku, Yokohama, 226-8501, Japan
| | - Shutaro Takahashi
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 B-57 Nagatsuta, Midori-ku, Yokohama, 226-8501, Japan
| | - Naohiko Shimada
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 B-57 Nagatsuta, Midori-ku, Yokohama, 226-8501, Japan
| | - Atsushi Maruyama
- Department of Life Science and Technology, Tokyo Institute of Technology, 4259 B-57 Nagatsuta, Midori-ku, Yokohama, 226-8501, Japan
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4
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Elsebai MF, Habib ESE. Blood pH and COVID-19. Arch Pharm (Weinheim) 2023; 356:e2200558. [PMID: 36690587 DOI: 10.1002/ardp.202200558] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 12/31/2022] [Accepted: 01/02/2023] [Indexed: 01/25/2023]
Abstract
The coronavirus disease 2019 (COVID-19) pandemic is a worldwide war. Raising the blood pH might be a crucial strategy to chase COVID-19. The human blood is slightly alkaline, which is essential for cell metabolism, normal physiology, and balanced immunity since all of these biological processes are pH-dependent. Varieties of physiologic derangements occur when the blood pH is disrupted. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) proliferates in acidic blood that magnifies the severity of COVID-19. On the other side, blood acidemia is linked to increased morbidity and mortality because of its complications on immunity, especially in the elderly and in critical diseases such as cancer, musculoskeletal degradation, renal, cardiac, and pulmonary disorders, which result in many pathological disorders such as osteomalacia, and disturbing the hematopoiesis. Additionally, acidemia of the blood facilitates viral infection and progression. Thus, correcting the acid-base balance might be a crucial strategy for the treatment of COVID-19, which might be attributed to the distraction of the viral spike protein to its cognate receptor angiotensin-converting enzyme 2 and supporting the over-taxed immunity.
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Affiliation(s)
- Mahmoud Fahmi Elsebai
- Department of Pharmacognosy, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
| | - El-Sayed E Habib
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, Egypt
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5
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Menchikov LG, Shestov AA, Popov AV. Warburg Effect Revisited: Embodiment of Classical Biochemistry and Organic Chemistry. Current State and Prospects. BIOCHEMISTRY (MOSCOW) 2023; 88:S1-S20. [PMID: 37069111 DOI: 10.1134/s0006297923140018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The Nobel Prize Winner (1931) Dr. Otto H. Warburg had established that the primary energy source of the cancer cell is aerobic glycolysis (the Warburg effect). He also postulated the hypothesis about "the prime cause of cancer", which is a matter of debate nowadays. Contrary to the hypothesis, his discovery was recognized entirely. However, the discovery had almost vanished in the heat of battle about the hypothesis. The prime cause of cancer is essential for the prevention and diagnosis, yet the effects that influence tumor growth are more important for cancer treatment. Due to the Warburg effect, a large amount of data has been accumulated on biochemical changes in the cell and the organism as a whole. Due to the Warburg effect, the recovery of normal biochemistry and oxygen respiration and the restoration of the work of mitochondria of cancer cells can inhibit tumor growth and lead to remission. Here, we review the current knowledge on the inhibition of abnormal glycolysis, neutralization of its consequences, and normalization of biochemical parameters, as well as recovery of oxygen respiration of a cancer cell and mitochondrial function from the point of view of classical biochemistry and organic chemistry.
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Affiliation(s)
- Leonid G Menchikov
- N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, 119991, Russian Federation
| | - Alexander A Shestov
- University of Pennsylvania, Department of Pathology and Laboratory Medicine, Perelman Center for Advanced Medicine, Philadelphia, PA 19104, USA
| | - Anatoliy V Popov
- University of Pennsylvania, Department of Radiology, Philadelphia, PA 19104, USA.
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6
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Melatonin Treatment Triggers Metabolic and Intracellular pH Imbalance in Glioblastoma. Cells 2022; 11:cells11213467. [DOI: 10.3390/cells11213467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 10/26/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
Metabolic rewiring in glioblastoma (GBM) is linked to intra- and extracellular pH regulation. In this study, we sought to characterize the role of melatonin on intracellular pH modulation and metabolic consequences to identify the mechanisms of action underlying melatonin oncostatic effects on GBM tumor initiating cells. GBM tumor initiating cells were treated at different times with melatonin (1.5 and 3.0 mM). We analyzed melatonin’s functional effects on GBM proliferation, cell cycle, viability, stemness, and chemo-radiosensitivity. We then assessed the effects of melatonin on GBM metabolism by analyzing the mitochondrial and glycolytic parameters. We also measured the intracellular and extracellular pH. Finally, we tested the effects of melatonin on a mouse subcutaneous xenograft model. We found that melatonin downregulated LDHA and MCT4, decreasing lactate production and inducing a decrease in intracellular pH that was associated with an increase in ROS and ATP depletion. These changes blocked cell cycle progression and induced cellular death and we observed similar results in vivo. Melatonin’s cytotoxic effects on GBM were due, at least in part, to intracellular pH modulation, which has emerged as a newly identified mechanism, providing new insights into the oncostatic effect of melatonin on GBM.
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Winnand P, Boernsen KO, Bodurov G, Lammert M, Hölzle F, Modabber A. Evaluation of electrolyte element composition in human tissue by laser-induced breakdown spectroscopy (LIBS). Sci Rep 2022; 12:16391. [PMID: 36180727 PMCID: PMC9525258 DOI: 10.1038/s41598-022-20825-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 09/19/2022] [Indexed: 11/22/2022] Open
Abstract
Laser-induced breakdown spectroscopy (LIBS) enables the direct measurement of cell electrolyte concentrations. The utility of LIBS spectra in biomarker studies is limited because these studies rarely consider basic physical principles. The aim of this study was to test the suitability of LIBS spectra as an analytical method for biomarker assays and to evaluate the composition of electrolyte elements in human biomaterial. LIBS as an analytical method was evaluated by establishing KCl calibration curves to demonstrate linearity, by the correct identification of emission lines with corresponding reference spectra, and by the feasibility to use LIBS in human biomaterial, analyzing striated muscle tissues from the oral regions of two patients. Lorentzian peak fit and peak area calculations resulted in better linearity and reduced shot-to-shot variance. Correct quantitative measurement allowed for differentiation of human biomaterial between patients, and determination of the concentration ratios of main electrolytes within human tissue. The clinical significance of LIBS spectra should be evaluated using peak area rather than peak intensity. LIBS might be a promising tool for analyzing a small group of living cells. Due to linearity, specificity and robustness of the proposed analytical method, LIBS could be a component of future biomarker studies.
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Affiliation(s)
- Philipp Winnand
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany.
| | - K Olaf Boernsen
- Advanced Osteotomy Tools AG, Wallstraße 6, 4051, Basel, Switzerland
| | - Georgi Bodurov
- Advanced Osteotomy Tools AG, Wallstraße 6, 4051, Basel, Switzerland
| | - Matthias Lammert
- Institute of Pathology, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Frank Hölzle
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Ali Modabber
- Department of Oral and Maxillofacial Surgery, University Hospital RWTH Aachen, Pauwelsstraße 30, 52074, Aachen, Germany
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FTO-dependent N(6)-Methyladenosine regulates the progression of endometriosis via the ATG5/PKM2 Axis. Cell Signal 2022; 98:110406. [PMID: 35839979 DOI: 10.1016/j.cellsig.2022.110406] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2022] [Revised: 06/26/2022] [Accepted: 07/08/2022] [Indexed: 12/25/2022]
Abstract
N6-methyladenosine (m6A), the most abundant internal modification on mRNAs in eukaryotes, plays a role in endometriosis (EMs). However, the underlying mechanism remains largely unclear. Here, we found that FTO is downregulated in EMs; and plays an important role in regulating glycolysis, proliferation, and metastasis of ectopic endometriotic stromal cells (EESCs) by targeting ATG5. We demonstrated that FTO promotes ATG5 expression in a m6A-dependent manner, and further studies revealed that PKM2 is a target of ATG5. Upon FTO overexpression, increased ATG5 protein expression at low m6A levels inhibited the expression of PKM2, thereby reducing the glycolysis level of EESCs. In addition, we demonstrated through in vitro functional experiments that FTO regulates glycolysis, proliferation, and metastasis of EESCs through the ATG5/PKM2 axis. In conclusion, these findings reveal the functional importance of the m6A methylation mechanism of FTO in regulating the development of EMs, which expands our understanding of this interaction, which is crucial for the development of therapeutic strategies for EMs.
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9
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Acidic and basic self-assembling peptide and peptide-graphene oxide hydrogels: characterisation and effect on encapsulated nucleus pulposus cells. Acta Biomater 2022; 143:145-158. [PMID: 35196554 DOI: 10.1016/j.actbio.2022.02.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 02/11/2022] [Accepted: 02/16/2022] [Indexed: 12/28/2022]
Abstract
Extracellular pH can have a profound effect on cell metabolism, gene and protein expression. Nucleus pulposus (NP) cells, for example, under acidic conditions accelerate the production of degradative enzymes and pro-inflammatory cytokines, leading ultimately to intervertebral disc degeneration, a major cause of back pain. Self-assembling peptide hydrogels constitute a well-established class of biomaterials that could be exploited as pH-tunable platform to investigate cell behaviour under normal and non-physiological pH. In this paper we formulated acidic (pH = 4) and basic (pH = 9) hydrogels, from the same octapeptide FEFKFEFK (F8) (F = phenyalanine, E = glutamic acid, K = lysine), to test the effect of non-physiological pH on encapsulated NP cells. Similarly, graphene oxide-containing F8 hydrogels (GO-F8) were formulated as stiffer analogues. Acidic and basic hydrogels showed peculiar morphologies and rheological properties, with all systems able to buffer within 30 minutes of exposure to cell culture media. NP cells seeded in acidic F8 hydrogels showed a more catabolic phenotype compared to basic hydrogels, with increased gene expression of degradative enzymes (MMP-3, ADAMTS-4), neurotrophic factors (NGF and BDNF) and NF-κB p65 phosphorylation. Acidic GO-F8 hydrogels also induced a catabolic response, although milder than basic counterparts and with the highest gene expression of characteristic NP-matrix components, aggrecan and collagen II. In all systems, the cellular response had a peak within 3 days of encapsulation, thereafter decreasing over 7 days, suggesting a 'transitory' effect of hydrogel pH on encapsulated cells. This work gives an insight on the effect of pH (and pH buffering) on encapsulated NP cells and offers new designs of low and high pH peptide hydrogels for 3D cell culture studies. STATEMENT OF SIGNIFICANCE: We have recently shown the potential of graphene oxide - self-assembling peptide hybrid hydrogels for NP cell culture and regeneration. Alongside cell carrier, self-assembling peptide hydrogels actually provide a versatile pH-tunable platform for biological studies. In this work we decided to explore the effect of non-physiological pH (and pH buffering) on encapsulated NP cells. Our approach allows the formulation of both acidic and basic hydrogels, starting from the same peptide sequence. We showed that the initial pH of the scaffold does not affect significantly cell response to encapsulation, but the presence of GO results in lower inflammatory levels and higher NP matrix protein production. This platform could be exploited to study the effect of pH on different cell types whose behaviour can be pH-dependent.
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10
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Liao Y, Jing T, Zhang F, He P. In Situ Monitoring of Extracellular K + Using the Potentiometric Mode of Scanning Electrochemical Microscopy with a Carbon-Based Potassium Ion-Selective Tip. Anal Chem 2022; 94:4078-4086. [PMID: 35213803 DOI: 10.1021/acs.analchem.2c00002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The expression of potassium channels can be related to the occurrence and development of tumors. Their change would affect K+ outflow. Thus, in situ monitoring of extracellular K+ shows a great significance. Herein, the dual-functional K+ ion-selective electrode as the scanning electrochemical microscopy (SECM) tip (K+-ISE SECM tip) has been developed for in situ monitoring of the extracellular K+. Based on multi-wall carbon nanotubes as a transduction layer, the K+-ISE SECM tip realizes both the plotting of approach curves to position the tip for in situ detection and the recording of potential responses. It shows a near Nernstian response, good selectivity, and excellent stability. Based on these characteristics, it was used to in situ monitor K+ concentrations ([K+]o) of three breast cancer cell lines (MCF-7, MDA-MB-231, and SK-BR-3 cells) at 3 μm above the cell, and [K+]o of MDA-MB-231 cells show the highest value, followed by MCF-7 cells and SK-BR-3 cells. K+ outflow induced by electrical stimulation or pH changes of the culture environment (Δ[K+]o) was further determined, and the possible mechanism of K+ outflow was investigated with 4-aminopyridin (4-AP). MCF-7 cells present the largest value of Δ[K+]o, followed by MDA-MB-231 cells and SK-BR-3 cells at all the stimulation potentials, and pH 6.50 shows the greatest impact on K+ outflow of the three cell lines. The pretreatment of 4-AP changed K+ outflow, probably due to the regulation of voltage-gated channels. These findings provide insight into a deep understanding of the microenvironment influence on K+ outflow, thereby reflecting the possible mechanism of potassium channels.
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Affiliation(s)
- Yuxian Liao
- School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai 200241, P.R. China
| | - Ting Jing
- School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai 200241, P.R. China
| | - Fan Zhang
- School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai 200241, P.R. China
| | - Pingang He
- School of Chemistry and Molecular Engineering, East China Normal University, 500 Dongchuan Road, Shanghai 200241, P.R. China
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Hyder F, Khan MH. Dysregulated proton and sodium gradients highlight cancer invasion and proliferation. Transl Oncol 2021; 16:101310. [PMID: 34896853 PMCID: PMC8681017 DOI: 10.1016/j.tranon.2021.101310] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Revised: 11/15/2021] [Accepted: 12/05/2021] [Indexed: 11/29/2022] Open
Abstract
The hallmarks of cancer all directly linked to proton and sodium imbalances, where reduced extracellular pH and salinity are both the resultant of oncogenic metabolic changes in the tumor microenvironment and are supported by upregulated cellular mechanisms like carbonic anhydrase 9 (CA IX) and sodium proton exchanger (NHE). The dysregulated proton and sodium gradients highlight cancer invasion and proliferation and can be imaged by merging of 23Na and 1H magnetic resonance techniques.
Acidity and salinity of the extracellular fluid, reflecting degrees of acid and sodium contents respectively, regulate essential cellular functions in health and disease, especially cancer. Tumor invasiveness is enhanced by the acidic extracellular milieu as a consequence of upregulated aerobic glycolysis. But recent discoveries also suggest that enhanced proliferative mitosis, which also hallmarks cancer, is impacted by interstitial salinity. Abnormal transmembrane proton/sodium gradients lead to pathophysiological alterations at the cellular level. These novel perspectives mandate pioneering imaging of extracellular acidity and salinity, preferably monitored simultaneously. By dissecting the interplay between dysregulated pH and electrolyte imbalance within the tumor habitat, these biomarkers hold promise for early cancer diagnosis and tracking therapies, from chemotherapy to immunotherapy.
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Affiliation(s)
- Fahmeed Hyder
- Department of Biomedical Engineering, Yale University, New Haven, CT, United States of America; Department of Radiology & Biomedical Imaging, Yale University, New Haven, CT, United States of America; Magnetic Resonance Research Center (MRRC), Yale University, New Haven, CT, United States of America; Quantitative Neuroimaging with Magnetic Resonance (QNMR) Research Program, Yale University, New Haven, CT, United States of America.
| | - Muhammad H Khan
- Department of Biomedical Engineering, Yale University, New Haven, CT, United States of America; Magnetic Resonance Research Center (MRRC), Yale University, New Haven, CT, United States of America
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Ozcan M, Aydemir D, Bacanlı M, Anlar HG, Ulusu NN, Aksoy Y. Protective Effects of Antioxidant Chlorophyllin in Chemically Induced Breast Cancer Model In vivo. Biol Trace Elem Res 2021; 199:4475-4488. [PMID: 33624221 DOI: 10.1007/s12011-021-02585-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 01/08/2021] [Indexed: 10/22/2022]
Abstract
Glutathione-related enzymes belong to the protection mechanism of the cells against harmful oxidative damage and chemicals. Glutathione S-transferase (GST) is frequently over-expressed in various cancer cells and is involved in drug resistance. Chlorophyllin is an antioxidant molecule interfering with the GST P1-1 activity. The purpose of this study is to evaluate the short- and long-term protective effects of chlorophyllin as an antioxidant molecule on DNA damage, antioxidant enzyme activities, trace elements, and minerals in chemically induced breast cancer model in vivo. In our study, N-methyl-N-nitrosourea (MNU) was used for inducing breast carcinogenesis in female Sprague-Dawley rats. A total of 36 rats were divided into groups as short term and long term. Each group was divided into four sub-groups as control group received physiological saline solution (n = 3), Chl group (n = 5) received chlorophyllin, MNU group (n = 5) was administered MNU, and Chl + MNU group (n = 5) was treated with both chlorophyllin and MNU. Results illustrated that chlorophyllin had a significant anti-genotoxic effect in the short term, and glutathione-related enzyme activities were protected by chlorophyllin treatment in MNU-induced breast cancer model. Additionally, MNU administration impaired mineral and trace element levels including Na, Mg, K, Fe, Zn, and Co in the liver, kidney, spleen, heart, and tumor tissues; however, adverse effects of MNU were recovered upon chlorophyllin treatment in the indicated tissues of the rats. In conclusion, chlorophyllin can be used as an antioxidant molecule to ameliorate adverse effects of MNU by enhancing antioxidant enzyme activities and regulating trace element and mineral balance in several organs and tumor tissue in the breast cancer model.
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Affiliation(s)
- Mehmet Ozcan
- Department of Medical Biochemistry, Hacettepe University Faculty of Medicine, Sıhhiye, 06100, Ankara, Turkey
- Department of Medical Biochemistry, Bulent Ecevit University Faculty of Medicine, Zonguldak, Turkey
| | - Duygu Aydemir
- Department of Medical Biochemistry, Koc University, School of Medicine, Istanbul, Turkey
- Koc University Research Center for Translational Medicine (KUTTAM), Istanbul, Turkey
| | - Merve Bacanlı
- Department of Pharmaceutical Toxicology, University of Health Sciences Gulhane Faculty of Pharmacy, Ankara, Turkey
| | - Hatice Gul Anlar
- Department of Pharmaceutical Toxicology, Bulent Ecevit University Faculty of Pharmacy, Zonguldak, Turkey
| | - N Nuray Ulusu
- Department of Medical Biochemistry, Koc University, School of Medicine, Istanbul, Turkey
- Koc University Research Center for Translational Medicine (KUTTAM), Istanbul, Turkey
| | - Yasemin Aksoy
- Department of Medical Biochemistry, Hacettepe University Faculty of Medicine, Sıhhiye, 06100, Ankara, Turkey.
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Abstract
Artificial receptors able to recognise biologically relevant molecules or ions have gained interest in the chemical community because they offer a plethora of posibilities. Molecular cage compounds are polycyclic compounds with a cavity designed for the encapsulation of guest species. Once inside the host cavity, the substrate can be transported through membranes and protected from the action of enzymes or other reactive species, thus offering the possibility of interfering with biological systems. Commonly, enzymes have been an inspiration for chemists in the search and design of defined cavities for different purposes. However, the chemical preparation of molecular cages has struggled with many synthetic challenges but this effort is worthwhile as they are a very promising tool for many applications ranging from sensing, delivery, purification or even promotion of/prevention from chemical modifications. Since the early reports at the end of the 60s, this field has experienced a growing interest; this review summarises the progress in the preparation and study of cage-like compounds highlighting their importance in biological applications.
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Affiliation(s)
- Lucía Tapia
- Department of Biological Chemistry, Institute for Advanced Chemistry of Catalonia, IQAC-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.
| | - Ignacio Alfonso
- Department of Biological Chemistry, Institute for Advanced Chemistry of Catalonia, IQAC-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.
| | - Jordi Solà
- Department of Biological Chemistry, Institute for Advanced Chemistry of Catalonia, IQAC-CSIC, Jordi Girona 18-26, 08034 Barcelona, Spain.
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FLIM-Based Intracellular and Extracellular pH Measurements Using Genetically Encoded pH Sensor. BIOSENSORS-BASEL 2021; 11:bios11090340. [PMID: 34562930 PMCID: PMC8468847 DOI: 10.3390/bios11090340] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 09/07/2021] [Accepted: 09/10/2021] [Indexed: 02/04/2023]
Abstract
The determination of pH in live cells and tissues is of high importance in physiology and cell biology. In this report, we outline the process of the creation of SypHerExtra, a genetically encoded fluorescent sensor that is capable of measuring extracellular media pH in a mildly alkaline range. SypHerExtra is a protein created by fusing the previously described pH sensor SypHer3s with the neurexin transmembrane domain that targets its expression to the cytoplasmic membrane. We showed that with excitation at 445 nm, the fluorescence lifetime of both SypHer3s and SypHerExtra strongly depend on pH. Using FLIM microscopy in live eukaryotic cells, we demonstrated that SypHerExtra can be successfully used to determine extracellular pH, while SypHer3s can be applied to measure intracellular pH. Thus, these two sensors are suitable for quantitative measurements using the FLIM method, to determine intracellular and extracellular pH in a range from pH 7.5 to 9.5 in different biological systems.
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Teixeira V, Martins TS, Prinz WA, Costa V. Target of Rapamycin Complex 1 (TORC1), Protein Kinase A (PKA) and Cytosolic pH Regulate a Transcriptional Circuit for Lipid Droplet Formation. Int J Mol Sci 2021; 22:9017. [PMID: 34445723 PMCID: PMC8396576 DOI: 10.3390/ijms22169017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 08/12/2021] [Accepted: 08/19/2021] [Indexed: 11/16/2022] Open
Abstract
Lipid droplets (LDs) are ubiquitous organelles that fulfill essential roles in response to metabolic cues. The identification of several neutral lipid synthesizing and regulatory protein complexes have propelled significant advance on the mechanisms of LD biogenesis in the endoplasmic reticulum (ER). However, our understanding of signaling networks, especially transcriptional mechanisms, regulating membrane biogenesis is very limited. Here, we show that the nutrient-sensing Target of Rapamycin Complex 1 (TORC1) regulates LD formation at a transcriptional level, by targeting DGA1 expression, in a Sit4-, Mks1-, and Sfp1-dependent manner. We show that cytosolic pH (pHc), co-regulated by the plasma membrane H+-ATPase Pma1 and the vacuolar ATPase (V-ATPase), acts as a second messenger, upstream of protein kinase A (PKA), to adjust the localization and activity of the major transcription factor repressor Opi1, which in turn controls the metabolic switch between phospholipid metabolism and lipid storage. Together, this work delineates hitherto unknown molecular mechanisms that couple nutrient availability and pHc to LD formation through a transcriptional circuit regulated by major signaling transduction pathways.
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Affiliation(s)
- Vitor Teixeira
- Yeast Signalling Networks, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.S.M.); (V.C.)
- Yeast Signalling Networks, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
| | - Telma S. Martins
- Yeast Signalling Networks, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.S.M.); (V.C.)
- Yeast Signalling Networks, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
| | - William A. Prinz
- Laboratory of Cell and Molecular Biology, National Institute of Diabetes and Digestive and Kidney Diseases, NIH, Bethesda, MD 20892, USA;
| | - Vítor Costa
- Yeast Signalling Networks, i3S—Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; (T.S.M.); (V.C.)
- Yeast Signalling Networks, IBMC—Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal
- ICBAS—Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
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16
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Lam SF, Bishop KW, Mintz R, Fang L, Achilefu S. Calcium carbonate nanoparticles stimulate cancer cell reprogramming to suppress tumor growth and invasion in an organ-on-a-chip system. Sci Rep 2021; 11:9246. [PMID: 33927272 PMCID: PMC8084943 DOI: 10.1038/s41598-021-88687-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Accepted: 04/15/2021] [Indexed: 02/08/2023] Open
Abstract
The acidic microenvironment of solid tumors induces the propagation of highly invasive and metastatic phenotypes. However, simulating these conditions in animal models present challenges that confound the effects of pH modulators on tumor progression. To recapitulate the tumor microenvironment and isolate the effect of pH on tumor viability, we developed a bifurcated microfluidic device that supports two different cell environments for direct comparison. RFP-expressing breast cancer cells (MDA-MB-231) were cultured in treatment and control chambers surrounded by fibrin, which received acid-neutralizing CaCO3 nanoparticles (nanoCaCO3) and cell culture media, respectively. Data analysis revealed that nanoCaCO3 buffered the pH within the normal physiological range and inhibited tumor cell proliferation compared to the untreated control (p < 0.05). Co-incubation of cancer cells and fibroblasts, followed by nanoCaCO3 treatment showed that the nanoparticles selectively inhibited the growth of the MDA-MB-231 cells and reduced cellular migration of these cells with no impact on the fibroblasts. Sustainable decrease in the intracellular pH of cancer cells treated with nanoCaCO3 indicates that the extracellular pH induced cellular metabolic reprogramming. These results suggest that the nanoCaCO3 can restrict the aggressiveness of tumor cells without affecting the growth and behavior of the surrounding stromal cells.
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Affiliation(s)
- Sandra F Lam
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Kevin W Bishop
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Rachel Mintz
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
| | - Lei Fang
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Biomedical Engineering, Washington University, St. Louis, MO, USA
| | - Samuel Achilefu
- Department of Radiology, Washington University School of Medicine, St. Louis, MO, USA.
- Department of Biomedical Engineering, Washington University, St. Louis, MO, USA.
- Department of Medicine, Washington University School of Medicine, St. Louis, MO, USA.
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA.
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17
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Metabolic Shifts as the Hallmark of Most Common Diseases: The Quest for the Underlying Unity. Int J Mol Sci 2021; 22:ijms22083972. [PMID: 33921428 PMCID: PMC8068795 DOI: 10.3390/ijms22083972] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/31/2021] [Accepted: 04/03/2021] [Indexed: 12/13/2022] Open
Abstract
A hyper-specialization characterizes modern medicine with the consequence of classifying the various diseases of the body into unrelated categories. Such a broad diversification of medicine goes in the opposite direction of physics, which eagerly looks for unification. We argue that unification should also apply to medicine. In accordance with the second principle of thermodynamics, the cell must release its entropy either in the form of heat (catabolism) or biomass (anabolism). There is a decreased flow of entropy outside the body due to an age-related reduction in mitochondrial entropy yield resulting in increased release of entropy in the form of biomass. This shift toward anabolism has been known in oncology as Warburg-effect. The shift toward anabolism has been reported in most diseases. This quest for a single framework is reinforced by the fact that inflammation (also called the immune response) is involved in nearly every disease. This strongly suggests that despite their apparent disparity, there is an underlying unity in the diseases. This also offers guidelines for the repurposing of old drugs.
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18
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Khan MH, Walsh JJ, Mihailović JM, Mishra SK, Coman D, Hyder F. Imaging the transmembrane and transendothelial sodium gradients in gliomas. Sci Rep 2021; 11:6710. [PMID: 33758290 PMCID: PMC7987982 DOI: 10.1038/s41598-021-85925-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 03/08/2021] [Indexed: 11/29/2022] Open
Abstract
Under normal conditions, high sodium (Na+) in extracellular (Na+e) and blood (Na+b) compartments and low Na+ in intracellular milieu (Na+i) produce strong transmembrane (ΔNa+mem) and weak transendothelial (ΔNa+end) gradients respectively, and these manifest the cell membrane potential (Vm) as well as blood–brain barrier (BBB) integrity. We developed a sodium (23Na) magnetic resonance spectroscopic imaging (MRSI) method using an intravenously-administered paramagnetic polyanionic agent to measure ΔNa+mem and ΔNa+end. In vitro 23Na-MRSI established that the 23Na signal is intensely shifted by the agent compared to other biological factors (e.g., pH and temperature). In vivo 23Na-MRSI showed Na+i remained unshifted and Na+b was more shifted than Na+e, and these together revealed weakened ΔNa+mem and enhanced ΔNa+end in rat gliomas (vs. normal tissue). Compared to normal tissue, RG2 and U87 tumors maintained weakened ΔNa+mem (i.e., depolarized Vm) implying an aggressive state for proliferation, whereas RG2 tumors displayed elevated ∆Na+end suggesting altered BBB integrity. We anticipate that 23Na-MRSI will allow biomedical explorations of perturbed Na+ homeostasis in vivo.
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Affiliation(s)
- Muhammad H Khan
- Department of Biomedical Engineering, Yale University, N143 TAC (MRRC), 300 Cedar Street, New Haven, CT, 06520, USA.
| | - John J Walsh
- Department of Biomedical Engineering, Yale University, N143 TAC (MRRC), 300 Cedar Street, New Haven, CT, 06520, USA
| | - Jelena M Mihailović
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, 06520, USA
| | - Sandeep K Mishra
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, 06520, USA
| | - Daniel Coman
- Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, 06520, USA
| | - Fahmeed Hyder
- Department of Biomedical Engineering, Yale University, N143 TAC (MRRC), 300 Cedar Street, New Haven, CT, 06520, USA. .,Department of Radiology and Biomedical Imaging, Yale University, New Haven, CT, 06520, USA.
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19
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Zhang L, Liu SY, Yang X, Wang YQ, Cheng YX. TMEM206 is a potential prognostic marker of hepatocellular carcinoma. Oncol Lett 2020; 20:174. [PMID: 32934741 PMCID: PMC7475639 DOI: 10.3892/ol.2020.12035] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 06/30/2020] [Indexed: 01/15/2023] Open
Abstract
Transmembrane proteins are involved in the transportation of materials into and out of cells. The transmembrane protein (TMEM) family is a collection of poorly described transmembrane proteins that serve important roles in tumor development and progression. A number of TMEM proteins have been discovered. A newly discovered TMEM protein, TMEM206, transports ions across the membrane under physiological and pathological conditions, generating an acidic environment, which serves an important role in the microenvironment. However, the prognostic value and regulatory mechanisms of action of TMEM206 in tumors is unclear. The aim of the present study was to evaluate the prognostic value and regulation mechanisms of TMEM206 in tumors. Firstly, the expression of TMEM206 in tumors and normal tissues was assessed using the GEPIA and Oncomine databases and the results revealed that TMEM206 expression increased or decreased depending on the type of tumor. Subsequently, using the Human Protein Atlas and the Kaplan-Meier plotter, the findings of the present study revealed that TMEM206 is related to the prognosis of hepatocellular carcinoma. In order to explore the mechanism of TMEM206 in promoting tumor progression, GEO and cBioPortal were used to determine genes that may be co-expressed with TMEM206. MetaScape was used to identify the signaling pathways that TMEM206 may participate in. Finally, miRWalk, miRDB and TargetScan were used to identify miRNAs that may regulate the expression of TMEM206 and the findings revealed that 2 miRNA (hsa-miR-325 and hsa-miR-510-5p) were involved. In conclusion, upregulation of TMEM206 is associated with poor prognosis in patients with hepatocellular carcinoma.
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Affiliation(s)
- Li Zhang
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Shi-Yi Liu
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Xiao Yang
- Department of Obstetrics and Gynecology, Peking University People's Hospital, Beijing 100044, P.R. China
| | - Yan-Qing Wang
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
| | - Yan-Xiang Cheng
- Department of Obstetrics and Gynecology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
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20
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Harguindey S, Alfarouk K, Polo Orozco J, Fais S, Devesa J. Towards an Integral Therapeutic Protocol for Breast Cancer Based upon the New H +-Centered Anticancer Paradigm of the Late Post-Warburg Era. Int J Mol Sci 2020; 21:E7475. [PMID: 33050492 PMCID: PMC7589677 DOI: 10.3390/ijms21207475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 12/13/2022] Open
Abstract
A brand new approach to the understanding of breast cancer (BC) is urgently needed. In this contribution, the etiology, pathogenesis, and treatment of this disease is approached from the new pH-centric anticancer paradigm. Only this unitarian perspective, based upon the hydrogen ion (H+) dynamics of cancer, allows for the understanding and integration of the many dualisms, confusions, and paradoxes of the disease. The new H+-related, wide-ranging model can embrace, from a unique perspective, the many aspects of the disease and, at the same time, therapeutically interfere with most, if not all, of the hallmarks of cancer known to date. The pH-related armamentarium available for the treatment of BC reviewed here may be beneficial for all types and stages of the disease. In this vein, we have attempted a megasynthesis of traditional and new knowledge in the different areas of breast cancer research and treatment based upon the wide-ranging approach afforded by the hydrogen ion dynamics of cancer. The concerted utilization of the pH-related drugs that are available nowadays for the treatment of breast cancer is advanced.
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Affiliation(s)
- Salvador Harguindey
- Department of Oncology, Institute of Clinical Biology and Metabolism, 01004 Vitoria, Spain;
| | - Khalid Alfarouk
- Department of Pharmacology, Al-Ghad International Colleges for Applied Medical Sciences, Al-Madinah Al-Munawarah 42316, Saudi Arabia and Alfarouk Biomedical Research LLC, Tampa, FL 33617, USA;
| | - Julián Polo Orozco
- Department of Oncology, Institute of Clinical Biology and Metabolism, 01004 Vitoria, Spain;
| | - Stefano Fais
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità (National Institute of Health), 00161 Rome, Italy;
| | - Jesús Devesa
- Scientific Direction, Foltra Medical Centre, 15886 Teo, Spain;
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21
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Alfarouk KO, Ahmed SBM, Elliott RL, Benoit A, Alqahtani SS, Ibrahim ME, Bashir AHH, Alhoufie STS, Elhassan GO, Wales CC, Schwartz LH, Ali HS, Ahmed A, Forde PF, Devesa J, Cardone RA, Fais S, Harguindey S, Reshkin SJ. The Pentose Phosphate Pathway Dynamics in Cancer and Its Dependency on Intracellular pH. Metabolites 2020; 10:E285. [PMID: 32664469 PMCID: PMC7407102 DOI: 10.3390/metabo10070285] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 07/02/2020] [Accepted: 07/06/2020] [Indexed: 12/21/2022] Open
Abstract
The Pentose Phosphate Pathway (PPP) is one of the key metabolic pathways occurring in living cells to produce energy and maintain cellular homeostasis. Cancer cells have higher cytoplasmic utilization of glucose (glycolysis), even in the presence of oxygen; this is known as the "Warburg Effect". However, cytoplasmic glucose utilization can also occur in cancer through the PPP. This pathway contributes to cancer cells by operating in many different ways: (i) as a defense mechanism via the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) to prevent apoptosis, (ii) as a provision for the maintenance of energy by intermediate glycolysis, (iii) by increasing genomic material to the cellular pool of nucleic acid bases, (iv) by promoting survival through increasing glycolysis, and so increasing acid production, and (v) by inducing cellular proliferation by the synthesis of nucleic acid, fatty acid, and amino acid. Each step of the PPP can be upregulated in some types of cancer but not in others. An interesting aspect of this metabolic pathway is the shared regulation of the glycolytic and PPP pathways by intracellular pH (pHi). Indeed, as with glycolysis, the optimum activity of the enzymes driving the PPP occurs at an alkaline pHi, which is compatible with the cytoplasmic pH of cancer cells. Here, we outline each step of the PPP and discuss its possible correlation with cancer.
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Affiliation(s)
- Khalid O. Alfarouk
- Alfarouk Biomedical Research LLC, Temple Terrace, FL 33617, USA
- American Biosciences Inc., New York, NY 10913, USA;
- Al-Ghad International College for Applied Medical Sciences, Al-Madinah Al-Munawarah 42316, Saudi Arabia
| | | | - Robert L. Elliott
- The Elliott-Elliott-Baucom Breast Cancer Research and Treatment Center, Baton Rouge, LA 70806, USA;
- The Sallie A. Burdine Breast Foundation, Baton Rouge, LA 70806, USA;
| | - Amanda Benoit
- The Sallie A. Burdine Breast Foundation, Baton Rouge, LA 70806, USA;
| | - Saad S. Alqahtani
- Clinical Pharmacy Department, College of Pharmacy, Jazan University, Jazan 45142, Saudi Arabia;
| | - Muntaser E. Ibrahim
- Institute of Endemic Diseases, University of Khartoum, Khartoum 11111, Sudan; (M.E.I.); (A.H.H.B.)
| | - Adil H. H. Bashir
- Institute of Endemic Diseases, University of Khartoum, Khartoum 11111, Sudan; (M.E.I.); (A.H.H.B.)
| | - Sari T. S. Alhoufie
- Department of Clinical Laboratory Sciences, Faculty of Applied Medical Sciences, Taibah University, Al-Madinah Al-Munwarah 42353, Saudi Arabia;
| | - Gamal O. Elhassan
- Unaizah College of Pharmacy, Qassim University, Unaizah 56264, Saudi Arabia;
| | | | | | - Heyam S. Ali
- Department of Pharmaceutics, Faculty of Pharmacy, University of Khartoum, Khartoum 11111, Sudan;
| | - Ahmed Ahmed
- Department of Oesphogastric and General Surgery, University Hospitals of Leicester, Leicester LE5 4PW, UK;
| | - Patrick F. Forde
- CancerResearch@UCC, Western Gateway Building, University College Cork, Cork T12 XF62, Ireland;
| | - Jesus Devesa
- Scientific Direction, Foltra Medical Centre, Travesía de Montouto 24, 15886 Teo, Spain;
| | - Rosa A. Cardone
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 90126 Bari, Italy; (R.A.C.); (S.J.R.)
| | - Stefano Fais
- Department of Oncology and Molecular Medicine, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy;
| | - Salvador Harguindey
- Department of Oncology, Institute for Clinical Biology and Metabolism, 01004 Vitoria, Spain;
| | - Stephan J. Reshkin
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 90126 Bari, Italy; (R.A.C.); (S.J.R.)
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