Copper-dependent ATP7B up-regulation drives the resistance of TMEM16A-overexpressing head-and-neck cancer models to platinum toxicity

Platinum-containing drugs such as cisplatin and carboplatin are routinely used for the treatment of many solid tumors including squamous cell carcinoma of the head and neck (SCCHN). However, SCCHN resistance to platinum compounds is well documented. The resistance to platinum has been linked to the activity of divalent transporter ATP7B, which pumps platinum from the cytoplasm into lysosomes, decreasing its concentration in the cytoplasm. Several cancer models show increased expression of ATP7B; however, the reason for such an increase is not known. Here we show a strong positive correlation between mRNA levels of TMEM16A and ATP7B in human SCCHN tumors. TMEM16A overexpression and depletion in SCCHN cell lines caused parallel changes in the ATP7B mRNA levels. The ATP7B increase in TMEM16A-overexpressing cells was reversed by suppression of NADPH oxidase 2 (NOX2), by the antioxidant N-Acetyl-Cysteine (NAC) and by copper chelation using cuprizone and bathocuproine sulphonate (BCS). Pretreatment with either chelator significantly increased cisplatin's sensitivity, particularly in the context of TMEM16A overexpression. We propose that increased oxidative stress in TMEM16A-overexpressing cells liberates the chelated copper in the cytoplasm, leading to the transcriptional activation of ATP7B expression. This, in turn, decreases the efficacy of platinum compounds by promoting their vesicular sequestration. We think that such a new explanation of the mechanism of SCCHN tumors’ platinum resistance identifies novel approach to treating these tumors.

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Prognostic role of DFNA5 in head and neck squamous cell carcinoma revealed by systematic expression analysis

BMC Cancer ◽

10.1186/s12885-021-08692-w ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Zhiguo Liu ◽

Hongyan Liu ◽

Qian Dong ◽

Hongyu Li ◽

Bin Zhang ◽

...

Keyword(s):

Squamous Cell Carcinoma ◽

Cell Carcinoma ◽

Head And Neck ◽

Squamous Cell ◽

Prognostic Value ◽

Prognostic Significance ◽

Neck Squamous Cell Carcinoma ◽

Mrna Levels ◽

Strong Positive Correlation ◽

Normal Tissues

Abstract Background The gasdermin E gene (GSDME, also known as DFNA5) is mutated in familial aging-related hearing loss. Recent studies have also revealed that the expression of DFNA5 is suppressed in many cancer types; however, little is known about the function of DFNA5 in head and neck squamous cell carcinoma (HNSCC). Accordingly, the aim of the present study was to evaluate the expression of DFNA5 and explore its prognostic value in HNSCC. Result We used a set of bioinformatics tools, including Oncomine, TIMER, TISIDB, cBioPortal, and GEPIA, to analyze the expression of DFNA5 in patients with HNSCC from public databases. Kaplan-Meier plotter was used to evaluate the potential prognostic significance of DFNA5. DFNA5 mRNA levels were significantly higher in HNSCC tissues than in normal tissues, and high DFNA5 expression was correlated with worse survival. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that DFNA5 expression has a strong positive correlation with cell adhesion and the integrin signaling pathway, whereas its expression was negatively correlated with the levels of infiltrating B cells (cor = − 0.223, P = 8.57e-07) and CD8 T cells (cor = − 0.223, P = 2.99e-07). Conclusion This study demonstrates that DFNA5 expression has prognostic value for HNSCC patients. Moreover, these results suggest that regulation of lymphocyte infiltration is the mechanism underlying the function of DFNA5 in HNSCC.

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Plasmodium Falciparum Regulates Transcriptional Output by Modulating The Activity of RNA Polymerase II Rather Than Its Recruitment

10.21203/rs.3.rs-74869/v1 ◽

2020 ◽

Author(s):

Ragini Rai Khandelia ◽

Aarthi Mohan ◽

Lei Zhu ◽

Jie Zheng ◽

Mark Stephen Featherstone ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Transcriptional Activation ◽

Transcriptional Control ◽

Wide Distribution ◽

Developmental Cycle ◽

Mrna Levels ◽

Strong Positive Correlation ◽

Coding Region

Abstract Background The asexual phase of the unicellular eukaryotic parasite Plasmodium falciparum takes place in the human red blood cell (RBC). During the 48 h between RBC infection and the release of new progeny – the intraerythrocytic developmental cycle (IDC) – transcripts levels for most of the parasite’s ~5,772 genes are set by the integration of transcriptional and post-transcriptional processes. Transcription of eukaryotic protein coding genes is carried out by RNA polymerase II (RNAPII) whose functional states are reflected by the phosphorylation status of serine residues at positions 2 and 5 within the so-called heptad repeats within the C-terminal domain (CTD) of the catalytic subunit, RPB1; unphosphorylated or Ser5-phosphorylated RNAPII correspond to uninitiated and initiating states, while phosphorylation at Ser2 is associated with the processive elongating form of the polymerase. Transcriptional control over the IDC could impinge on RNAPII recruitment, initiation, and conversion to processive elongation. To distinguish the contribution of these potential regulatory steps to transcriptional control during infection, we used ChIP-seq and RNA-seq to determine the genome-wide distribution of three RNAPII phosphoisoforms as well as total RNAPII and correlated occupancy with mRNA levels across the three stages of the IDC.ResultsWe find that most genes are occupied by RNAPII along the length of the coding region at all stages of the IDC, regardless of transcript output, with RNAPII accumulation of all forms strongly biased toward the coding region. Total RNAPII levels at a given gene are relatively constant across the IDC. By contrast, occupancy by the elongating form of the polymerase shows a strong positive correlation with mRNA abundance. ConclusionsThese observations reveal that transcriptional activation during the IDC is not regulated primarily at the level of RNAPII recruitment, but rather through the conversion of RNAPII to its processive elongating form. Our results have implications for the expected roles of enhancers and transcription factors in the parasite and support a major role for the control of transcriptional pausing.

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Prognostic Role of DFNA5 in Head and Neck Squamous Cell Carcinoma Revealed by Systematic Expression Analysis

10.21203/rs.3.rs-114898/v1 ◽

2020 ◽

Author(s):

Zhiguo Liu ◽

Hongyan Liu ◽

Qian Dong ◽

Hongyu Li ◽

Bin Zhang ◽

...

Keyword(s):

Squamous Cell Carcinoma ◽

Cell Carcinoma ◽

Head And Neck ◽

Squamous Cell ◽

Prognostic Value ◽

Prognostic Significance ◽

Neck Squamous Cell Carcinoma ◽

Mrna Levels ◽

Strong Positive Correlation ◽

Normal Tissues

Abstract The gasdermin E gene (GSDME, also known as DFNA5) is mutated in familial aging-related hearing loss. Recent studies have also revealed that the expression of DFNA5 is suppressed in many cancer types; however, little is known about the function of DFNA5 in head and neck squamous cell carcinoma (HNSCC). Accordingly, the aim of the present study was to evaluate the expression of DFNA5 and explore its prognostic value in HNSCC. We used a set of bioinformatics tools, including Oncomine, TIMER, TISIDB, cBioPortal, and GEPIA, to analyze the expression of DFNA5 in patients with HNSCC from public databases. Kaplan-Meier plotter was used to evaluate the potential prognostic significance of DFNA5. DFNA5 mRNA levels were significantly higher in HNSCC tissues than in normal tissues, and high DFNA5 expression was correlated with worse survival. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses showed that DFNA5 expression has a strong positive correlation with cell adhesion and the integrin signaling pathway, whereas its expression was negatively correlated with the levels of infiltrating B cells (cor = –0.223, P = 8.57e-07) and CD8 T cells (cor = –0.223, P = 2.99e-07). Overall, this study demonstrates that DFNA5 expression has prognostic value for HNSCC patients. Moreover, these results suggest that regulation of lymphocyte infiltration is the mechanism underlying the function of DFNA5 in HNSCC.

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Use of Oxidative Stress Responses to Determine the Efficacy of Inactivation Treatments on Cryptosporidium Oocysts

Microorganisms ◽

10.3390/microorganisms9071463 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1463

Author(s):

Tamirat Tefera Temesgen ◽

Kristoffer Relling Tysnes ◽

Lucy Jane Robertson

Keyword(s):

Oxidative Stress ◽

Stress Responses ◽

Target Genes ◽

Cryptosporidium Oocyst ◽

Drinking Water Treatment ◽

Proof Of Concept ◽

Environmental Matrices ◽

Oocyst Wall ◽

Novel Approach ◽

Cryptosporidium Oocysts

Cryptosporidium oocysts are known for being very robust, and their prolonged survival in the environment has resulted in outbreaks of cryptosporidiosis associated with the consumption of contaminated water or food. Although inactivation methods used for drinking water treatment, such as UV irradiation, can inactivate Cryptosporidium oocysts, they are not necessarily suitable for use with other environmental matrices, such as food. In order to identify alternative ways to inactivate Cryptosporidium oocysts, improved methods for viability assessment are needed. Here we describe a proof of concept for a novel approach for determining how effective inactivation treatments are at killing pathogens, such as the parasite Cryptosporidium. RNA sequencing was used to identify potential up-regulated target genes induced by oxidative stress, and a reverse transcription quantitative PCR (RT-qPCR) protocol was developed to assess their up-regulation following exposure to different induction treatments. Accordingly, RT-qPCR protocols targeting thioredoxin and Cryptosporidium oocyst wall protein 7 (COWP7) genes were evaluated on mixtures of viable and inactivated oocysts, and on oocysts subjected to various potential inactivation treatments such as freezing and chlorination. The results from the present proof-of-concept experiments indicate that this could be a useful tool in efforts towards assessing potential technologies for inactivating Cryptosporidium in different environmental matrices. Furthermore, this approach could also be used for similar investigations with other pathogens.

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Creatine Alleviates Doxorubicin-Induced Liver Damage by Inhibiting Liver Fibrosis, Inflammation, Oxidative Stress, and Cellular Senescence

Nutrients ◽

10.3390/nu13010041 ◽

2020 ◽

Vol 13 (1) ◽

pp. 41

Author(s):

Nouf Aljobaily ◽

Michael J. Viereckl ◽

David S. Hydock ◽

Hend Aljobaily ◽

Tsung-Yen Wu ◽

...

Keyword(s):

Oxidative Stress ◽

Dna Methylation ◽

Body Weight ◽

Liver Fibrosis ◽

Liver Damage ◽

Cellular Senescence ◽

Weight Ratio ◽

Mrna Levels ◽

Body Weight Ratio ◽

Chromosomal Stability

Background: Treatment with the chemotherapy drug doxorubicin (DOX) may lead to toxicities that affect non-cancer cells including the liver. Supplementing the diet with creatine (Cr) has been suggested as a potential intervention to minimize DOX-induced side effects, but its effect in alleviating DOX-induced hepatoxicity is currently unknown. Therefore, we aimed to examine the effects of Cr supplementation on DOX-induced liver damage. Methods: Male Sprague-Dawley rats were fed a diet supplemented with 2% Cr for four weeks, 4% Cr for one week followed by 2% Cr for three more weeks, or control diet for four weeks. Animals then received either a bolus i.p. injection of DOX (15 mg/kg) or saline as a placebo. Animals were then sacrificed five days-post injection and markers of hepatoxicity were analyzed using the liver-to-body weight ratio, aspartate transaminase (AST)-to- alanine aminotransferase (ALT) ratio, alkaline phosphatase (ALP), lipemia, and T-Bilirubin. In addition, hematoxylin and eosin (H&E) staining, Picro-Sirius Red staining, and immunofluorescence staining for CD45, 8-OHdG, and β-galactosidase were performed to evaluate liver morphology, fibrosis, inflammation, oxidative stress, and cellular senescence, respectively. The mRNA levels for biomarkers of liver fibrosis, inflammation, oxidative stress, and senescence-related genes were measured in liver tissues. Chromosomal stability was evaluated using global DNA methylation ELISA. Results: The ALT/AST ratio and liver to body weight ratio tended to increase in the DOX group, and Cr supplementation tended to attenuate this increase. Furthermore, elevated levels of liver fibrosis, inflammation, oxidative stress, and senescence were observed with DOX treatment, and Cr supplementation prior to DOX treatment ameliorated this hepatoxicity. Moreover, DOX treatment resulted in chromosomal instability (i.e., altered DNA methylation profile), and Cr supplementation showed a tendency to restore chromosomal stability with DOX treatment. Conclusion: The data suggest that Cr protected against DOX-induced hepatotoxicity by attenuating fibrosis, inflammation, oxidative stress, and senescence.

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Oxidative Stress Is Increased in Combined Oral Contraceptives Users and Is Positively Associated with High-Sensitivity C-Reactive Protein

Molecules ◽

10.3390/molecules26041070 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1070

Author(s):

Sabina Cauci ◽

Serena Xodo ◽

Cinzia Buligan ◽

Chiara Colaninno ◽

Mattia Barbina ◽

...

Keyword(s):

Oxidative Stress ◽

High Sensitivity ◽

Low Grade ◽

Strong Positive Correlation ◽

Obese Women ◽

C Reactive Protein ◽

Oxidative Stress Biomarkers ◽

Free Oxygen Radical ◽

Reactive Protein ◽

Healthy Women

Information concerning the mechanisms underlying oxidative stress and low-grade inflammation in young healthy women predisposing eventually to future diseases is scarce. We investigated the relationship of oxidative stress and high-sensitivity C-reactive protein (hsCRP) in fertile-age women by oral combined contraceptive (OC) use. Caucasian Italian healthy non-obese women (n = 290; 100 OC-users; 190 non-OC-users; mean age 23.2 ± 4.7 years) were analyzed. Blood hydroperoxides, as oxidative stress biomarkers, were assessed by Free Oxygen Radical Test (FORT). Serum hsCRP was determined by an ultra-sensitive method (hsCRP). Markedly elevated oxidative stress (≥400 FORT Units) was found in 77.0% of OC-users and 1.6% of non-OC-users, odds ratio (OR) = 209, 95% CI = 60.9–715.4, p < 0.001. Elevated hsCRP levels ≥ 2.0 mg/L, considered risky for cardiovascular diseases (CVDs), were found in 41.0% of OC-users and 9.5% of non-OC-users, OR = 6.6, 95%CI 3.5–12.4, p < 0.001. Hydroperoxides were strongly positively correlated to hsCRP in all women (rs = 0.622, p < 0.001), in OC-users (rs = 0.442, p < 0.001), and in non-OC-users (rs = 0.426, p < 0.001). Women with hydroperoxides ≥ 400 FORT Units were eight times as likely to have hsCRP ≥ 2 mg/L. In non-OC-users only, hydroperoxides values were positively correlated with weight and body mass index, but negatively correlated with red meat, fish and chocolate consumption. Our research is the first finding a strong positive correlation of serum hydroperoxides with hsCRP, a marker of low-grade chronic inflammation, in young healthy women. Further research is needed to elucidate the potential role of these two biomarkers in OC-use associated side-effects, like thromboembolism and other CVDs.

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IκBα targeting promotes oxidative stress-dependent cell death

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-01921-x ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Giovanna Carrà ◽

Giuseppe Ermondi ◽

Chiara Riganti ◽

Luisella Righi ◽

Giulia Caron ◽

...

Keyword(s):

Oxidative Stress ◽

Cell Fate ◽

Protein Interactions ◽

In Silico ◽

Inverse Correlation ◽

Ros Production ◽

Gene Encoding ◽

Specific Expression ◽

Novel Approach ◽

Stress Dependent

Abstract Background Oxidative stress is a hallmark of many cancers. The increment in reactive oxygen species (ROS), resulting from an increased mitochondrial respiration, is the major cause of oxidative stress. Cell fate is known to be intricately linked to the amount of ROS produced. The direct generation of ROS is also one of the mechanisms exploited by common anticancer therapies, such as chemotherapy. Methods We assessed the role of NFKBIA with various approaches, including in silico analyses, RNA-silencing and xenotransplantation. Western blot analyses, immunohistochemistry and RT-qPCR were used to detect the expression of specific proteins and genes. Immunoprecipitation and pull-down experiments were used to evaluate protein-protein interactions. Results Here, by using an in silico approach, following the identification of NFKBIA (the gene encoding IκBα) amplification in various cancers, we described an inverse correlation between IκBα, oxidative metabolism, and ROS production in lung cancer. Furthermore, we showed that novel IκBα targeting compounds combined with cisplatin treatment promote an increase in ROS beyond the tolerated threshold, thus causing death by oxytosis. Conclusions NFKBIA amplification and IκBα overexpression identify a unique cancer subtype associated with specific expression profile and metabolic signatures. Through p65-NFKB regulation, IκBα overexpression favors metabolic rewiring of cancer cells and distinct susceptibility to cisplatin. Lastly, we have developed a novel approach to disrupt IκBα/p65 interaction, restoring p65-mediated apoptotic responses to cisplatin due to mitochondria deregulation and ROS-production.

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Sesamin Modulates Tyrosine Hydroxylase, Superoxide Dismutase, Catalase, Inducible No Synthase and Interleukin-6 Expression in Dopaminergic Cells Under Mpp+-Induced Oxidative Stress

Oxidative Medicine and Cellular Longevity ◽

10.4161/oxim.1.1.6958 ◽

2008 ◽

Vol 1 (1) ◽

pp. 54-62 ◽

Cited By ~ 41

Author(s):

Vicky Lahaie-Collins ◽

Julie Bournival ◽

Marilyn Plouffe ◽

Julie Carange ◽

Maria-Grazia Martinoli

Keyword(s):

Oxidative Stress ◽

Superoxide Dismutase ◽

Tyrosine Hydroxylase ◽

Protein Expression ◽

Pc12 Cells ◽

Interleukin 6 ◽

Estrogen Receptor Alpha ◽

Strong Increase ◽

Mrna Levels ◽

Neuronal Pc12 Cells

Oxidative stress is regarded as a mediator of nerve cell death in several neurodegenerative disorders, such as Parkinson's disease. Sesamin, a lignan mainly found in sesame oil, is currently under study for its anti-oxidative and possible neuroprotective properties. We used 1-methyl-4-phenyl-pyridine (MPP+) ion, the active metabolite of the potent parkinsonism-causing toxin 1-methyl-4-phenyl-1,2,5,6-tetrahydropyridine, to produce oxidative stress and neurodegeneration in neuronal PC12 cells, which express dopamine, as well as neurofilaments. Our results show that picomolar doses of sesamin protected neuronal PC12 cells from MPP+-induced cellular death, as revealed by colorimetric measurements and production of reactive oxygen species. We also demonstrated that sesamin acted by rescuing tyrosine hydroxylase levels from MPP+-induced depletion. Sesamin, however, did not modulate dopamine transporter levels, and estrogen receptor-alpha and -beta protein expression. By examining several parameters of cell distress, we found that sesamin also elicited a strong increase in superoxide dismutase activity as well as protein expression and decreased catalase activity and the MPP+stimulated inducible nitric oxide synthase protein expression, in neuronal PC12 cells. Finally, sesamin possessed significant anti-inflammatory properties, as disclosed by its potential to reduce MPP+-induced interleukin-6 mRNA levels in microglia. From these studies, we determined the importance of the lignan sesamin as a neuroprotective molecule and its possible role in complementary and/or preventive therapies of neurodegenerative diseases.

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Thyroid hormone is required for the phenotype transitions induced by the pharmacological inhibition of calcineurin in adult soleus muscle of rats

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.00173.2007 ◽

2008 ◽

Vol 294 (1) ◽

pp. E69-E77 ◽

Cited By ~ 7

Author(s):

Nathalie Koulmann ◽

Lahoucine Bahi ◽

Florence Ribera ◽

Hervé Sanchez ◽

Bernard Serrurier ◽

...

Keyword(s):

Thyroid Hormone ◽

Soleus Muscle ◽

Hormone Deficiency ◽

Peroxisome Proliferator ◽

Mrna Levels ◽

Peroxisome Proliferator Activated Receptor ◽

Thyroid State ◽

Novel Approach ◽

A Subunit ◽

Calcineurin Inhibition

The present experiment was designed to examine the effects of hypothyroidism and calcineurin inhibition induced by cyclosporin A (CsA) administration on both contractile and metabolic soleus muscle phenotypes, with a novel approach to the signaling pathway controlling mitochondrial biogenesis. Twenty-eight rats were randomly assigned to four groups, normothyroid, hypothyroid, and orally treated with either CsA (25 mg/kg, N-CsA and H-CsA) or vehicle (N-Vh and H-Vh), for 3 wk. Muscle phenotype was estimated by the MHC profile and activities of oxidative and glycolytic enzymes. We measured mRNA levels of the peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α), the major regulator of mitochondrial content. We also studied the expression of the catalytic A-subunit of calcineurin (CnA) both at protein and transcript levels and mRNA levels of modulatory calcineurin inhibitor proteins (MCIP)-1 and -2, which are differentially regulated by calcineurin activity and thyroid hormone, respectively. CsA-administration induced a slow-to-fast MHC transition limited to the type IIA isoform, which is associated with increased oxidative capacities. Hypothyroidism strongly decreased both the expression of fast MHC isoforms and oxidative capacities. Effects of CsA administration on muscle phenotype were blocked in conditions of thyroid hormone deficiency. Changes in the oxidative profile were strongly related to PGC-1α changes and associated with phosphorylation of p38 MAPK. Calcineurin and MCIPs mRNA levels were decreased by both hypothyroidism and CsA without additive effects. Taken together, these results suggest that adult muscle phenotype is primarily under the control of thyroid state. Physiological levels of thyroid hormone are required for the effects of calcineurin inhibition on slow oxidative muscle phenotype.

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Myc and Human Papillomavirus Type 16 E7 Genes Cooperate To Immortalize Human Keratinocytes

Journal of Virology ◽

10.1128/jvi.00669-07 ◽

2007 ◽

Vol 81 (22) ◽

pp. 12689-12695 ◽

Cited By ~ 27

Author(s):

Xuefeng Liu ◽

Gary L. Disbrow ◽

Hang Yuan ◽

Vjekoslav Tomaić ◽

Richard Schlegel

Keyword(s):

Transcriptional Activation ◽

High Efficiency ◽

P53 Protein ◽

Significant Proportion ◽

Telomerase Activity ◽

Human Papillomaviruses ◽

Mrna Levels ◽

Crisis Period ◽

Cell Immortalization ◽

Immortalized Cells

ABSTRACT The E6 protein of the oncogenic human papillomaviruses (HPVs), in combination with the E7 protein, is essential for the efficient immortalization of human foreskin keratinocytes (HFKs). Since we recently demonstrated that E6 activates the human telomerase reverse transcriptase (hTERT) promoter via a Myc-dependent mechanism, we speculated that overexpressed Myc might be able to substitute for E6 in cell immortalization. Myc (similar to E6) was unable to immortalize HFKs when transduced alone, despite inducing high levels of telomerase activity. However, when transduced with E7, Myc immortalized HFKs following a brief but detectable crisis period. In contrast to E6 + E7-immortalized cells, the Myc + E7-immortalized cells expressed high levels of p53 protein as well as two p53-regulated proteins, p21 and hdm-2. The increase in p21 and hdm-2 proteins correlated directly with their mRNA levels, suggesting transcriptional activation of the respective genes by the overexpressed p53 protein. Interestingly, a significant proportion of the p53 protein in the Myc + E7-immortalized cells was localized to the cytoplasm, potentially due to interactions with the overexpressed hdm-2 protein. Regardless, cell immortalization by the Myc + E7 genes occurred independently of p53 degradation. Since we have already observed high-efficiency cell immortalization with the hTERT + E7 or E6 mutant (p53 degradation-defective) + E7 genes (i.e., no crisis period) that proceeds in the presence of high levels of p53, we hypothesize that the crisis period in the Myc + E7 cells is due not to the levels of the p53 protein but rather to unique properties of the Myc protein. The common factor in cell immortalization by the three gene sets (E6 + E7, Myc + E7, and hTERT + E7 genes) is the induction of telomerase activity.

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