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IR also indirectly induces DNA damage by stimulating reactive oxygen species (ROS) production

IR is known to induce EMT in vitro

p53 is activated in response to IR-induced DNA damage

IR paradoxically also promotes tumour recurrence and metastasis

DNA double-strand breaks (DSBs)

cancer cells undergoing EMT acquire invasive and metastatic properties

changes in the tumour microenvironment (TME)

IR seems to induce EMT and CSC phenotypes by regulating cellular metabolism

EMT, stemness, and oncogenic metabolism are known to be associated with resistance to radiotherapy and chemotherapy

Hanahan and Weinberg proposed ten hallmarks of cancer that alter cell physiology to enhance malignant growth: 1) sustained proliferation, 2) evasion of growth suppression, 3) cell death resistance, 4) replicative immortality, 5) evasion of immune destruction, 6) tumour-promoting inflammation, 7) activation of invasion and metastasis, 8) induction of angiogenesis, 9) genome instability, and 10) alteration of metabolism

EMT is a developmental process that plays critical roles in embryogenesis, wound healing, and organ fibrosis

IR is known to induce stemness and metabolic alterations in cancer cells

transforming growth factor-β [TGF-β], epidermal growth factor [EGF]) and their associated signalling proteins (Wnt, Notch, Hedgehog, nuclear-factor kappa B [NF-κB], extracellular signal-regulated kinase [ERK], and phosphatidylinositol 3-kinase [PI3K]/Akt

activate EMT-inducing transcription factors, including Snail/Slug, ZEB1/δEF1, ZEB2/SIP1, Twist1/2, and E12/E47

Loss of E-cadherin is considered a hallmark of EMT

IR has been shown to induce EMT to enhance the motility and invasiveness of several cancer cells, including those of breast, lung, and liver cancer, and glioma cells

IR may increase metastasis in both the primary tumour site and in normal tissues under some circumstance

sublethal doses of IR have been shown to enhance the migratory and invasive behaviours of glioma cells

ROS are known to play an important role in IR-induced EMT

High levels of ROS trigger cell death by causing irreversible damage to cellular components such as proteins, nucleic acids, and lipids, whereas low levels of ROS have been shown to promote tumour progression—including tumour growth, invasion, and metastasis

hypoxia-inducible factor-1 (HIF-1) is involved in IR-induced EMT

Treatment with the N-acetylcysteine (NAC), a general ROS scavenger, prevents IR-induced EMT, adhesive affinity, and invasion of breast cancer cells

Snail has been shown to play a crucial role in IR-induced EMT, migration, and invasion

IR activates the p38 MAPK pathway, which contributes to the induction of Snail expression to promote EMT and invasion

NF-κB signalling that promotes cell migration

ROS promote EMT to allow cancer cells to avoid hostile environments

HIF-1 is a heterodimer composed of an oxygen-sensitive α subunit and a constitutively expressed β subunit.

Under normoxia, HIF-1α is rapidly degraded, whereas hypoxia induces stabilisation and accumulation of HIF-1α

levels of HIF-1α mRNA are enhanced by activation of the PI3K/Akt/mammalian target of rapamycin (mTOR)

IR is known to increase stabilisation and nuclear accumulation of HIF-1α, since hypoxia is a major condition for HIF-1 activation

IR induces vascular damage that causes hypoxia

ROS is implicated in IR-induced HIF-1 activation

IR causes the reoxygenation of hypoxic cancer cells to increase ROS production, which leads to the stabilisation and nuclear accumulation of HIF-1

IR increases glucose availability under reoxygenated conditions that promote HIF-1α translation by activating the Akt/mTOR pathway

The stabilised HIF-1α then translocates to the nucleus, dimerizes with HIF-1β, and increases gene expression— including the expression of essential EMT regulators such as Snail—to induce EMT, migration, and invasion

TGF-β signalling has been shown to play a crucial role in IR-induced EMT

AP-1 transcription factor is involved in IR-induced TGF-β1 expression

Wnt/β-catenin signalling is also implicated in IR-induced EMT

Notch signalling is known to be involved in IR-induced EMT

IR also increases Notch-1 expression [99]. Notch-1 is known to induce EMT by upregulating Snail

PAI-1 signalling is also implicated in IR-induced Akt activation that increases Snail levels to induce EMT

EGFR activation is known to be associated with IR-induced EMT, cell migration, and invasion by activating two downstream pathways: PI3K/Akt and Raf/MEK/ERK

ROS and RNS are also implicated in IR-induced EGFR activation

IR has also been shown to activate Hedgehog (Hh) signalling to induce EMT

IR has been shown to induce Akt activation through several signalling pathways (EGFR, C-X-C chemokine receptor type 4 [CXCR4]/C-X-C motif chemokine 12 [CXCL12], plasminogen activator inhibitor 1 [PAI-1]) and upstream regulators (Bmi1, PTEN) that promote EMT and invasion

CSCs possess a capacity for self-renewal, and they can persistently proliferate to initiate tumours upon serial transplantation, thus enabling them to maintain the whole tumour

Conventional cancer treatments kill most cancer cells, but CSCs survive due to their resistance to therapy, eventually leading to tumour relapse and metastasis

identification of CSCs, three types of markers are utilised: cell surface molecules, transcription factors, and signalling pathway molecules

CSCs express distinct and specific surface markers; commonly used ones are CD24, CD34, CD38, CD44, CD90, CD133, and ALDH

Transcription factors, including Oct4, Sox2, Nanog, c-Myc, and Klf4,

signalling pathways, including those of TGF-β, Wnt, Hedgehog, Notch, platelet-derived growth factor receptor (PDGFR), and JAK/STAT

microRNAs (miRNAs), including let-7, miR-22, miR-34a, miR-128, the miR-200 family, and miR-451

Non-CSCs can be reprogrammed to become CSCs by epigenetic and genetic changes

EMT-inducing transcription factors, such as Snail, ZEB1, and Twist1, are known to confer CSC properties

Signalling pathways involved in EMT, including those of TGF-β, Wnt, and Notch, have been shown to play important roles in inducing the CSC phenotype

TGF-β1 not only increases EMT markers (Slug, Twist1, β-catenin, N-cadherin), but also upregulates CSC markers (Oct4, Sox2, Nanog, Klf4) in breast and lung cancer cells

some CSC subpopulations arise independently of EMT

IR has been shown to induce the CSC phenotype in many cancers, including breast, lung, and prostate cancers, as well as melanoma

Genotoxic stress due to IR or chemotherapy promotes a CSC-like phenotype by increasing ROS production

IR has been shown to induce reprogramming of differentiated cancer cells into CSCs

In prostate cancer patients, radiotherapy increases the CD44+ cell population that exhibit CSC properties

IR also induces the re-expression of stem cell regulators, such as Sox2, Oct4, Nanog, and Klf4, to promote stemness in cancer cells

EMT-inducing transcription factors and signalling pathways, including Snail, STAT3, Notch signalling, the PI3K/Akt pathway, and the MAPK cascade, have been shown to play important roles in IR-induced CSC properties

STAT3 directly binds to the Snail promoter and increases Snail transcription, which induces the EMT and CSC phenotypes, in cisplatin-selected resistant cells

Other oncogenic metabolic pathways, including glutamine metabolism, the pentose phosphate pathway (PPP), and synthesis of fatty acids and cholesterol, are also enhanced in many cancers

metabolic reprogramming

HIF-1α, p53, and c-Myc, are known to contribute to oncogenic metabolism

metabolic reprogramming

tumour cells exhibit high mitochondrial metabolism as well as aerobic glycolysis

occurring within the same tumour

CSCs can be highly glycolytic-dependent or oxidative phosphorylation (OXPHOS)-dependen

mitochondrial function is crucial for maintaining CSC functionality

cancer cells depend on mitochondrial metabolism and increase mitochondrial production of ROS that cause pseudo-hypoxia

HIF-1 then enhances glycolysis

CAFs have defective mitochondria that lead to the cells exhibiting the Warburg effect; the cells take up glucose, and then secrete lactate to 'feed' adjacent cancer cells

lactate transporter, monocarboxylate transporter (MCT)

nutrient microenvironment

Epithelial cancer cells express MCT1, while CAFs express MCT4. MCT4-positive, hypoxic CAFs secrete lactate by aerobic glycolysis, and MCT1-expressing epithelial cancer cells then uptake and use that lactate as a substrate for the tricarboxylic acid (TCA) cycle

MCT4-positive cancer cells depend on glycolysis and then efflux lactate, while MCT1-positive cells uptake lactate and rely on OXPHOS

metabolic heterogeneity induces a lactate shuttle between hypoxic/glycolytic cells and oxidative/aerobic tumour cells

bulk tumour cells exhibit a glycolytic phenotype, with increased conversion of glucose to lactate (and enhanced lactate efflux through MCT4), CSC subsets depend on oxidative phosphorylation; most of the glucose entering the cells is converted to pyruvate to fuel the TCA cycle and the electron transport chain (ETC), thereby increasing mitochondrial ROS production

the major fraction of glucose is directed into the pentose phosphate pathway, to produce redox power through the generation of NADPH and ROS scavengers

HIF-1α, p53, and c-Myc, are known to contribute to oncogenic metabolism

regulatory molecules involved in EMT and CSCs, including Snail, Dlx-2, HIF-1, STAT3, TGF-β, Wnt, and Akt, are implicated in the metabolic reprogramming of cancer cells

HIF-1 induces the expression of glycolytic enzymes, including the glucose transporter GLUT, hexokinase, lactate dehydrogenase (LDH), and MCT, resulting in the glycolytic switch

HIF-1 represses the expression of pyruvate dehydrogenase kinase (PDK), which inhibits pyruvate dehydrogenase (PDH), thereby inhibiting mitochondrial activity

STAT3 has been implicated in EMT-induced metabolic changes as well

TGF-β and Wnt play important roles in the metabolic alteration of cancer cells

Akt is also implicated in the glycolytic switch and in promoting cancer cell invasiveness

EMT, invasion, metastasis, and stemness

pyruvate kinase M2 (PKM2), LDH, and pyruvate carboxylase (PC), are implicated in the induction of the EMT and CSC phenotypes

decreased activity of PKM2 is known to promote an overall shift in metabolism to aerobic glycolysis

LDH catalyses the bidirectional conversion of lactate to pyruvate

High levels of LDHA are positively correlated with the expression of EMT and CSC markers

IR has been shown to induce metabolic changes in cancer cells

IR enhances glycolysis by upregulating GAPDH (a glycolysis enzyme), and it increases lactate production by activating LDHA, which converts pyruvate to lactate

IR enhances glycolysis by upregulating GAPDH (a glycolysis enzyme), and it increases lactate production by activating LDHA, which converts pyruvate to lactate

IR also elevates MCT1 expression that exports lactate into the extracellular environment, leading to acidification of the tumour microenvironment

IR increases intracellular glucose, glucose 6-phosphate, fructose, and products of pyruvate (lactate and alanine), suggesting a role for IR in the upregulation of cytosolic aerobic glycolysis

Lactate can activate latent TGF-

lactate stimulates cell migration and enhances secretion of hyaluronan from CAF that promote tumour metastasis

promote tumour survival, growth, invasion, and metastasis; enhance the stiffness of the ECM; contribute to angiogenesis; and induce inflammation by releasing several growth factors and cytokines (TGF-β, VEGF, hepatocyte growth factor [HGF], PDGF, and stromal cell-derived factor 1 [SDF1]), as well as MMP

tumours recruit the host tissue’s blood vessel network to perform four mechanisms: angiogenesis (formation of new vessels), vasculogenesis (de novo formation of blood vessels from endothelial precursor cells), co-option, and modification of existing vessels within tissues.

immunosuppressive cells such as tumour-associated macrophages (TAM), MDSCs, and regulatory T cells, and the immunosuppressive cytokines, TGF-β and interleukin-10 (IL-10)

immunosuppressive cells such as tumour-associated macrophages (TAM), MDSCs, and regulatory T cells, and the immunosuppressive cytokines, TGF-β and interleukin-10 (IL-10)

intrinsic immunogenicity or induce tolerance

cancer immunoediting’

three phases: 1) elimination, 2) equilibrium, and 3) escape.

The third phase, tumour escape, is mediated by antigen loss, immunosuppressive cells (TAM, MDSCs, and regulatory T cells), and immunosuppressive cytokines (TGF-β and IL-10).

IR can elicit various changes in the TME, such as CAF activity-mediated ECM remodelling and fibrosis, cycling hypoxia, and an inflammatory response

IR activates CAFs to promote the release of growth factors and ECM modulators, including TGF-β and MMP

TGF-β directly influences tumour cells and CAFs, promotes tumour immune escape, and activates HIF-1 signalling

MMPs degrade ECM that facilitates angiogenesis, tumour cell invasion, and metastasis

IR also promotes MMP-2/9 activation in cancer cells to promote EMT, invasion, and metastasis

IR-induced Snail increases MMP-2 expression to promote EMT

Radiotherapy has the paradoxical side-effect of increasing tumour aggressiveness

IR promotes ROS production in cancer cells, which may induce the activation of oncogenes and the inactivation of tumour suppressors, which further promote oncogenic metabolism

Metabolic alterations

oncogenic metabolism

elicit various changes in the TME

Although IR activates an antitumour immune response, this signalling is frequently suppressed by tumour escape mechanisms

Other targets of HIF-1α include glucose transporter-1 (GLUT-1), the main transporter involved in glucose uptake [9,10]; lactate dehydrogenase V (LDHV), which is responsible for the conversion of pyruvate into lactate; pyruvate dehydrogenase kinase isozyme 1 (PDK1), which is responsible for the phosphorylation and consequent inactivation of pyruvate dehydrogenase (PDH); and carbonic anhydrase IX (CAIX), a hypoxia-related protein involved in pH regulation [11]. Alpha-methylacyl-CoA racemase (AMACR), pristanoyl-CoA oxidase (ACOX-3) and D-bifunctional protein (DBP), are also important fatty acid oxidation-related proteins in prostate cancer

the essential role played by the cross-talk between stroma and epithelium in carcinogenesis and prostate cancer progression has been increasingly recognised

strong membranous expression of MCT1 was consistently observed in cancer cells, suggesting a role for MCT1 in the transport of lactate into tumour cells from the acidic extracellular matrix, suggesting that lactate might be used as a fuel by oxidative cancer cells.

Our hypothesis is in agreement with those of Fiaschi et al.[17], who describe the metabolic reprogramming of CAFs towards the Warburg phenotype as a result of contact with prostate cancer cells

Using in vitro studies, they showed lactate production and efflux by de novo expressed MCT4 in CAFs and also demonstrated that, upon contact with CAFs, prostate cancer cells were reprogrammed towards aerobic metabolism, with an increase in lactate uptake via the lactate transporter MCT1.

pharmacological inhibition of MCT1-mediated lactate uptake dramatically affected PCa cell survival and tumour outgrowth

In this model, “energy transfer” or “metabolic coupling” between the tumour stroma and epithelial cancer cells fuels tumour growth and metastasis via oxidative mitochondrial metabolism in anabolic cancer cells

the concomitant expression of MCT1 in tumour cells and MCT4 in fibroblasts in the same tissue is clinically significant, and associated with poor prognosis.

The cytokine storm is a consequence of mitochondrial dysfunction

The cytokine storm is a consequence of mitochondrial dysfunction

The cytokine storm is a consequence of mitochondrial dysfunction

The cytokine storm is a consequence of mitochondrial dysfunction

Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity

Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity

Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity

Lipoic acid, Methylene Blue and Chlorine dioxide relieve COVID-19 spike protein toxicity

most diseases display a form of anabolism due to mitochondrial impairment

most diseases display a form of anabolism due to mitochondrial impairment

most diseases display a form of anabolism due to mitochondrial impairment

infection by Covid-19 follows a similar pattern

chronic inflammation

Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction

Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction

Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction

Long-term effects include redox shift and cellular anabolism as a result of the Warburg effect and mitochondrial dysfunction

infection by Covid-19 follows a similar pattern

unrelenting anabolism leads to the cytokine storm,

unrelenting anabolism leads to the cytokine storm,

unrelenting anabolism leads to the cytokine storm,

chronic inflammation

chronic inflammation

infection by Covid-19 follows a similar pattern

Lipoic acid and Methylene Blue have been shown to enhance the mitochondrial activity, relieve the Warburg effect and increase catabolism

Lipoic acid and Methylene Blue have been shown to enhance the mitochondrial activity, relieve the Warburg effect and increase catabolism

Lipoic acid and Methylene Blue have been shown to enhance the mitochondrial activity, relieve the Warburg effect and increase catabolism

Methylene Blue, Chlorine dioxide and Lipoic acid may help reduce long-term Covid-19 effects by stimulating the catabolism

Methylene Blue, Chlorine dioxide and Lipoic acid may help reduce long-term Covid-19 effects by stimulating the catabolism

Methylene Blue, Chlorine dioxide and Lipoic acid may help reduce long-term Covid-19 effects by stimulating the catabolism

direct consequence of redox iMeBalance, itself a consequence of decreased energy yield by the mitochondria

direct consequence of redox iMeBalance, itself a consequence of decreased energy yield by the mitochondria

mitochondrial dysfunction and increased levels of lactate, which are important characteristics of metabolic shift and Warburg effect in many diseases

mitochondrial dysfunction and increased levels of lactate, which are important characteristics of metabolic shift and Warburg effect in many diseases

increased lactate dehydrogenase activity (LDH) was observed in COVID-19 patients

increased lactate dehydrogenase activity (LDH) was observed in COVID-19 patients

almost every disease presents an increased anabolism

almost every disease presents an increased anabolism

cell division is the most sophisticated way to release entropy

cell division is the most sophisticated way to release entropy

transition from catabolism to anabolism is driven by a redox shift

transition from catabolism to anabolism is driven by a redox shift

viral spike protein binds to ACE2 receptor of the host cell [22,23].

redox signaling plays an important role in regulating immune function and inflammation, and disruptions in this signaling can lead to excessive cytokine production and immune system activation

Aging is associated with a poor control of the redox balance

thiol/disulfide homeostasis

reduced extracellular environment in the elderly and the increased susceptibility to Covid-19 infection

reduced extracellular environment in the elderly and the increased susceptibility to Covid-19 infection

Redox signaling tightly modulates the inflammatory response and oxidative stress has been reported in acute Covid-19

People at high risk are the elderly, patients suffering from metabolic syndrome such as obesity, or those suffering from chronic diseases such as cancer or inflammation

COVID-19 patients with severe disease have higher levels of oxidative stress markers and lower antioxidant levels

oxidative stress can activate the NLRP3 inflammasome, which is a protein complex that plays a key role in the cytokine storm

inflammation leads to the formation of ROS and RNS, while redox iMeBalance results in cellular damage, which in turn triggers an inflammatory response

persistently elevated mtROS triggers endothelial dysfunction and inflammation, which results in a vicious loop involving ROS, inflammation, and mitochondrial dysfunction

Damaged mitochondria releasing ROS induce inflammation via the NLRP3 inflammasome

Damaged mitochondria releasing ROS induce inflammation via the NLRP3 inflammasome

reduced environment during the cytokine storm

IL-2 is highly up-regulated in Covid-19 patients [37], and IL-2 is known to significantly stimulate the generation of NO in patients

Nitric acid is also the key mediator of IL-2-induced hypotension and vascular leak syndrome

mitochondrial dysfunction has been linked to the pathogenesis of Covid-19

mitochondrial dysfunction triggered by SARS-CoV-2 leads to damage to the mitochondria

mitochondrial dysfunction triggered by SARS-CoV-2 leads to damage to the mitochondria

As catabolism is decreased, entropy is released through anabolism

Elevated levels of lactate, a characteristic of the Warburg effect, were also reported in the high-risk Covid-19

elevated levels of ventricular lactic acid consistent with oxidative stress

A decrease of ΔΨm is implicated in several inflammation-related diseases

decrease in ΔΨm in leucocytes from Covid-19 patients

vaccinated with RNA or DNA vaccines triggering the synthesis of the viral spike protein in human cells

viral reactivation in varicella-zoster virus [55] or hepatitis [56], coagulopathy and resulting stroke and myocarditis following both DNA-based vaccines [57] and RNA-based vaccines

Covid-19, mitochondrial impairment

characteristic of the Warburg effect is present in almost every disease and appears to be a central feature in most of the hallmarks of cancer

inflammation, mitochondrial dysfunction and increased lactate concentrations in the extracellular fluid

In Covid-19, like any inflammation, there is a metabolic rewiring where cells rely on glycolysis

As the mitochondria are impaired, the infected cell cannot catabolize efficiently. It will release lactic acid in the blood stream

Striking similarities are seen between cancer, Alzheimer's disease and Covid-19, all related to the Warburg effect

Cancer, inflammation, Alzheimer's, and Parkinson's diseases share a common peculiarity, the inability of the cell to export entropy outside the body in the harmless form of heat

MEB relieves the Warburg effect [87], improves memory [77], is active in the treatment of depressive episodes [79,80] and reduces the importance of ischemic strokes

MEB relieves the Warburg effect [87], improves memory [77], is active in the treatment of depressive episodes [79,80] and reduces the importance of ischemic strokes

MEB has been shown to inhibit SARS-Cov-2 replication in vitro

MEB has been shown to inhibit SARS-Cov-2 replication in vitro

It has been shown that Covid-19-patients treated with MEB, have a significant reduction in hospital stay duration and mortality

MeB is an acceptor-donor molecule

MeB + can take a pair of electrons (of H atoms) and MeBH can release this pair easily, so that MeB is partially recycled like a catalyst

MeB acts as an electron bridge between a donor (FADH2, FMNH, NADH) and an acceptor (complex IV of ETC or oxygen itself)

As a coenzyme of pyruvate dehydrogenase (PDH), alpha-lipoic acid (ALA) initiates the formation of acetyl-CoA to feed the TCA cycle

ALA enhances the catabolism of carbon. cycle and therefore may reduce the Warburg effect and consequently, lactate production

Methylene Blue plays a similar role after the TCA cycle, by carrying electrons to complex IV of the electron transport chain

Drugs such as lipoic acid and MeB, which target the metabolism, decrease the redox shift by increasing catabolism

Two-Compartment Tumor Metabolism

Reverse Warburg Effect”, is that catabolic fibroblasts should promote tumor growth, without any increases in angiogenesis

when cancer cells use L-lactate as a mitochondrial fuel source, this metabolic phenotype is a predictor of lethal cancer metabolism

tumor microenvironment is intimately involved in tumor development and progression

mitochondrial dysregulation is likely the “root cause” of several human disease(s), and especially epithelial cancers

Both in vitro and in vivo studies have now provided convincing evidence that “activated” stromal fibroblasts, a.k.a., myofibroblasts, may play a critical role in initiating tumor recurrence, via paracrine interactions with adjacent tumor epithelial cells

A new hypothesis is that cancer is not a cell autonomous disease, but rather a disease of the tumor microenvironment

cancer cells behave as metabolic parasites, by inducing oxidative stress in adjacent normal fibroblasts

recent experimental evidence indicates that cancer-associated fibroblasts have a catabolic phenotype, and undergo autophagy and mitophagy, resulting in the onset of glycolytic metabolism, driving L-lactate production, and its release into the tumor microenvironment

oncogenic mutations in cancer cells lead to ROS production and the “secretion” of hydrogen peroxide species

oxidative stress and ROS, produced in cancer-associated fibroblasts, has a “bystander effect” on adjacent cancer cells, leading to DNA damage, genomic instability and aneuploidy, which appears to be driving tumor-stroma co-evolution

tumor cells produce and secrete hydrogen peroxide, thereby “fertilizing” the tumor microenvironment and driving the “reverse Warburg effect.”

This type of stromal metabolism then produces high-energy nutrients (lactate, ketones and glutamine), as well as recycled chemical building blocks (nucleotides, amino acids, fatty acids), to literally “feed” cancer cells

loss of stromal caveolin (Cav-1) is sufficient to drive mitochondrial dysfunction with increased glucose uptake in fibroblasts, mimicking the glycolytic phenotype of cancer-associated fibroblasts.

oxidative stress initiated in tumor cells is transferred to cancer-associated fibroblasts.

Then, cancer-associated fibroblasts show quantitative reductions in mitochondrial activity and compensatory increases in glucose uptake, as well as high ROS production

These findings may explain the prognostic value of a loss of stromal Cav-1 as a marker of a “lethal” tumor microenvironment

aerobic glycolysis takes place in cancer-associated fibroblasts, rather than in tumor cells, as previously suspected.

our results may also explain the “field effect” in cancer biology,5 as hydrogen peroxide secreted by cancer cells, and the propagation of ROS production, from cancer cells to fibroblasts, would create an increasing “mutagenic field” of ROS production, due to the resulting DNA damage

Interruption of this process, by addition of catalase (an enzyme that detoxifies hydrogen peroxide) to the tissue culture media, blocks ROS activity in cancer cells and leads to apoptotic cell death in cancer cells

In this new paradigm, cancer cells induce oxidative stress in neighboring cancer-associated fibroblasts

cancer-associated fibroblasts have the largest increases in glucose uptake

cancer cells secrete hydrogen peroxide, which induces ROS production in cancer-associated fibroblasts

Then, oxidative stress in cancer-associated fibroblast leads to decreases in functional mitochondrial activity, and a corresponding increase in glucose uptake, to fuel aerobic glycolysis

cancer cells show significant increases in mitochondrial activity, and decreases in glucose uptake

fibroblasts and cancer cells in co-culture become metabolically coupled, resulting in the development of a “symbiotic” or “parasitic” relationship.

cancer-associated fibroblasts undergo aerobic glycolysis (producing lactate), while cancer cells use oxidative mitochondrial metabolism.

We have previously shown that oxidative stress in cancer-associated fibroblasts drives a loss of stromal Cav-1, due to its destruction via autophagy/lysosomal degradation

a loss of stromal Cav-1 is sufficient to induce further oxidative stress, DNA damage and autophagy, essentially mimicking pseudo-hypoxia and driving mitochondrial dysfunction

loss of stromal Cav-1 is a powerful biomarker for identifying breast cancer patients with early tumor recurrence, lymph-node metastasis, drug-resistance and poor clinical outcome

this type of metabolism (aerobic glycolysis and autophagy in the tumor stroma) is characteristic of a lethal tumor micro-environment, as it fuels anabolic growth in cancer cells, via the production of high-energy nutrients (such as lactate, ketones and glutamine) and other chemical building blocks

the upstream tumor-initiating event appears to be the secretion of hydrogen peroxide

one such enzymatically-active protein anti-oxidant that may be of therapeutic use is catalase, as it detoxifies hydrogen peroxide to water

numerous studies show that “catalase therapy” in pre-clinical animal models is indeed sufficient to almost completely block tumor recurrence and metastasis

by eliminating oxidative stress in cancer cells and the tumor microenvironment,55 we may be able to effectively cut off the tumor's fuel supply, by blocking stromal autophagy and aerobic glycolysis

breast cancer patients show systemic evidence of increased oxidative stress and a decreased anti-oxidant defense, which increases with aging and tumor progression.68–70 Chemotherapy and radiation therapy then promote further oxidative stress.69 Unfortunately, “sub-lethal” doses of oxidative stress during cancer therapy may contribute to tumor recurrence and metastasis, via the activation of myofibroblasts.

a loss of stromal Cav-1 is associated with the increased expression of gene profiles associated with normal aging, oxidative stress, DNA damage, HIF1/hypoxia, NFκB/inflammation, glycolysis and mitochondrial dysfunction

cancer-associated fibroblasts show the largest increases in glucose uptake, while cancer cells show corresponding decreases in glucose uptake, under identical co-culture conditions

Thus, increased PET glucose avidity may actually be a surrogate marker for a loss of stromal Cav-1 in human tumors, allowing the rapid detection of a lethal tumor microenvironment.

it appears that astrocytes are actually the cell type responsible for the glucose avidity.

In the brain, astrocytes are glycolytic and undergo aerobic glycolysis. Thus, astrocytes take up and metabolically process glucose to lactate.7

Then, lactate is secreted via a mono-carboxylate transporter, namely MCT4. As a consequence, neurons use lactate as their preferred energy substrate

both astrocytes and cancer-associated fibroblasts express MCT4 (which extrudes lactate) and MCT4 is upregulated by oxidative stress in stromal fibroblasts.34

In accordance with the idea that cancer-associated fibroblasts take up the bulk of glucose, PET glucose avidity is also now routinely used to measure the extent of fibrosis in a number of human diseases, including interstitial pulmonary fibrosis, postsurgical scars, keloids, arthritis and a variety of collagen-vascular diseases.

PET glucose avidity and elevated serum inflammatory markers both correlate with poor prognosis in breast cancers.

PET signal over-estimates the actual anatomical size of the tumor, consistent with the idea that PET glucose avidity is really measuring fibrosis and inflammation in the tumor microenvironment.

human breast and lung cancer patients can be positively identified by examining their exhaled breath for the presence of hydrogen peroxide.

tumor cell production of hydrogen peroxide drives NFκB-activation in adjacent normal cells in culture6 and during metastasis,103 directly implicating the use of antioxidants, NFκB-inhibitors and anti-inflammatory agents, in the treatment of aggressive human cancers.

The serum level of LDH correlated with tumor burden and was thought to reflect the tumor’s growth and invasive potential

the majority of patients with advanced or metastatic disease could be detected to have extremely high serum level of LDH

strong evidence to support effective chemotherapy of full dose even in patients with high LDH level

LDH is a key enzyme in the process of energy production in cancer cells, it catalyzes the conversion of pyruvate to lactate in hypoxic conditions

its function in anaerobic metabolism, cancer cells grow even after their rapid proliferation that leads to low-oxygen conditions in the tumor microenvironment

LDH plays an important role in tumor progression and maintenance

inhibition of LDH inhibits tumor progression and has been considered for the therapeutic target of cancer energy metabolism

LDH levels are increased in response to tissue injury or during disease states

LDH could be a marker of tumor burden for advanced cancer patients

LR’s acid base balance is superior to that of NS’s

There were no significant differences between LR and NS groups in fibrinogen concentrations or platelet count

Total protein dropped

no significant differences in Hct (Table  1) or total protein between LR and NS groups

Bicarbonate HCO3- levels were decreased by hemorrhage but returned to pre-hemorrhage values by 3 h after LR resuscitation, whereas no return was observed with NS resuscitation

Na+ was increased after NS resuscitation

No changes in Na+ or K+ were observed

K+ did not change initially after NS resuscitation but was elevated at 6 h afterwards

Ca++ was similarly decreased

Cl- was elevated for 6 h after NS resuscitation, with no changes shown after LR resuscitation

PT was similarly prolonged by resuscitation with LR (from 11.2 ± 0.2 sec at baseline to 12.1 ± 0.2 sec at 6 h) and NS

Plasma aPTT was also similarly prolonged by resuscitation with LR (from 17.1 ± 0.5 sec baseline to 20.1 ± 1.2 sec at 6 h) or NS

NS resuscitation resulted in better oxygen delivery and oxygen delivery-to-oxygen demand ratio as an index of oxygen debt

NS had better tissue perfusion and oxygen metabolism than LR

LR resuscitation returned BE and bicarbonate to pre-hemorrhage levels within 3 h, but no return of BE or bicarbonate was observed for 6 hr with NS resuscitation

current blood bank guidelines state that LR should not be mixed with blood to prevent the risk of clot formation from calcium included in LR

LR resuscitation should not be given with blood through the same iv-line and crystalloids should be avoided in patients with blood transfusion

PT and aPTT were prolonged for 6 h after hemorrhage and resuscitation, suggesting a hypocoagulable states

potential thrombotic risk from LR resuscitation is unlikely.

we suspected that the blood pressure after NS resuscitation would be lower than that of LR due to its vasodilator effects

NS required a larger resuscitation volume and was associated with poor acid base status and elevated serum potassium in this model

NS required 50% more volume and was associated with a higher cardiac output and lower peripheral resistance, as compared to LR resuscitation

These differences are possibly due to the vasodilator effects from NS

an elevation of K+ was observed at 6 h post NS resuscitation, while no change of K+ was observed after LR resuscitation

The mechanism for the increase of K+ from NS is not fully known

NS is associated with vasodilator effects and the risks of metabolic acidosis and hyperkalemia

The process would include variable periods of hyperinsulinemia with the consequent systemic MYC activation of glycolysis, glutaminolysis, structural lipidogenesis and further exacerbation of hypoglycemia, the result of MYC's known role as an inhibitor of liver gluconeogenesis

The metabolic changes we describe in breast cancer arise in concert with IEM-like changes in oxidative phosphorylation as detected by increased values of the ratio lactate/pyruvate (Supplementary Table 2A, 2B) characteristic of Ox/Phos deficiency [25]. In our study, 76% (70/92) of the European breast cancer patients had lactate/pyruvate ratios values higher than the normal value of 25.8

four-fold higher frequency of cancer (including breast) in patients with energy metabolism disorders

growing recognition that cancer cells differ from their normal counterparts in their use of nutrients, synthesis of biomolecules and generation of energy

glutamine concentrations in the cancer patients were reduced to nearly 1/8 of the levels observed in the normal population

blood concentrations of aspartate (p = 1.7e-67, FDR = 8.3e-67) (Figure ​(Figure1E)1E) and glutamate (p = 6.4e-96, FDR = 6.2e-95) (Figure ​(Figure1F)1F) were nearly 10 fold higher than the normal ranges of 0–5 μM/L and 40 μM/L, respectively

glutamine consumption associated with parallel increases in glutamate and aspartate (Figure ​(Figure1A1A red arrows) is considered a hallmark of MYC-driven “glutaminolysis”

Gln/Glu ratio inversely correlates with i- late stage metabolic syndrome and with ii- increased chance of death

changes in glutamine consumption, reflected by the Gln/Glu ratio could provide a metabolic link between breast cancer initiation and diabetes, reflective of a systemic metabolic reprogramming from glucose to glutamine as the preferred source of precursors for biosynthetic reactions and cellular energy

lower Gln/Glu ratios inversely correlated with insulin resistance and the risk of diabetes

the metabolic dependencies of cancer characterized by excessive glycolysis, glutaminolysis and malignant lipidogenesis, previously considered a consequence of local tumor DNA aberration [23] could, instead, represent a systemic biochemical aberration that predates and very likely promotes tumorigenesis

these metabolic disturbances would be expected to remain extant after therapeutic interventions

accumulation of very long chain acylcarnitines such as C14:1-OH (p = 0.0, FDR = 0.0), C16 (p = 0.0, FDR = 0.0), C18 (p = 0.0, FDR = 0.0) and C18:1 (p = 1.73e-322, FDR = 1.16-321) and lipids containing VLCFA (lysoPC a C28:0) (p = 1.14-e95, FDR = 1.65e-95) in the blood of breast and colon cancer patients

Among the most powerful metabolic equations for MYC-activation is that which links the widely used MYC-driven desaturation marker ratio of SFA/MUFA to the MYC glutaminolysis-associated ratio of (Asp/Gln)

liver dysfunction shares many features with both IEM and cancer suggesting a role for hepatic dysfunction in carcinogenesis

cancer “conscripts” the human genome to meet its needs under conditions of systemic metabolic stress