RNA-binding proteins control gene expression and cell fate in the immune system.

RNA-binding proteins (RBPs) are essential for the development and function of the immune system. They interact dynamically with RNA to control its biogenesis and turnover by transcription-dependent and transcription-independent mechanisms. In this Review, we discuss the molecular mechanisms by which RBPs allow gene expression changes to occur at different speeds and to varying degrees, and which RBPs regulate the diversity of the transcriptome and proteome. These proteins are nodes for integration of transcriptional and signaling networks and are intimately linked to intermediary metabolism. They are essential components of regulatory feedback mechanisms that maintain immune tolerance and limit inflammation. The role of RBPs in malignancy and autoimmunity has led to their emergence as targets for the development of new therapeutic modalities.

The RNA-binding protein PTBP1 is necessary for B cell selection in germinal centers.

Antibody affinity maturation occurs in germinal centers (GCs), where B cells cycle between the light zone (LZ) and the dark zone. In the LZ, GC B cells bearing immunoglobulins with the highest affinity for antigen receive positive selection signals from helper T cells, which promotes their rapid proliferation. Here we found that the RNA-binding protein PTBP1 was needed for the progression of GC B cells through late S phase of the cell cycle and for affinity maturation. PTBP1 was required for proper expression of the c-MYC-dependent gene program induced in GC B cells receiving T cell help and directly regulated the alternative splicing and abundance of transcripts that are increased during positive selection to promote proliferation.

The RNA-binding protein HuR is essential for the B cell antibody response.

Post-transcriptional regulation of mRNA by the RNA-binding protein HuR (encoded by Elavl1) is required in B cells for the germinal center reaction and for the production of class-switched antibodies in response to thymus-independent antigens. Transcriptome-wide examination of RNA isoforms and their abundance and translation in HuR-deficient B cells, together with direct measurements of HuR-RNA interactions, revealed that HuR-dependent splicing of mRNA affected hundreds of transcripts, including that encoding dihydrolipoamide S-succinyltransferase (Dlst), a subunit of the 2-oxoglutarate dehydrogenase (α-KGDH) complex. In the absence of HuR, defective mitochondrial metabolism resulted in large amounts of reactive oxygen species and B cell death. Our study shows how post-transcriptional processes control the balance of energy metabolism required for the proliferation and differentiation of B cells.

Alternative splicing: a pivotal step between eukaryotic transcription and translation.

Alternative splicing was discovered simultaneously with splicing over three decades ago. Since then, an enormous body of evidence has demonstrated the prevalence of alternative splicing in multicellular eukaryotes, its key roles in determining tissue- and species-specific differentiation patterns, the multiple post- and co-transcriptional regulatory mechanisms that control it, and its causal role in hereditary disease and cancer. The emerging evidence places alternative splicing in a central position in the flow of eukaryotic genetic information, between transcription and translation, in that it can respond not only to various signalling pathways that target the splicing machinery but also to transcription factors and chromatin structure.

CFTR expression in human salivary gland acinar cells.

The key role of CFTR in secretory epithelia has been extensively documented. Additionally, CFTR plays a significant role in ion absorption in exocrine glands, including salivary and sweat glands. Most of the knowledge about CFTR expression comes from animal models such as the mouse or the rat, but there is limited information about CFTR expression in human tissues. In the present study, we assessed the expression of CFTR in human submandibular and parotid glands. Consistent with findings in rodent salivary glands, our immunolocalization studies show that CFTR is expressed in duct cells. However, CFTR expression in human salivary glands differs from that in rodents, as immunolocalization and single-cell RNA sequencing analysis from a previous study performed in the human parotid gland revealed the presence of CFTR protein and transcripts within a distinct cell cluster. Based on cell marker expression, this cluster corresponds to acinar cells. To obtain functional evidence supporting CFTR expression, we isolated human parotid acinar cells through collagenase digestion. Acinar cells displayed an anion conductance that was activated in response to cAMP-increasing agents and was effectively blocked by CFTRInh172, a known CFTR blocker. This study provides novel evidence of CFTR expression within acinar cells of human salivary glands. This finding challenges the established model positioning CFTR exclusively in duct cells from exocrine glands.NEW & NOTEWORTHY This study addresses the uncertainty about the impact of CFTR on human salivary gland function. We found CFTR transcripts in a subset of duct cells known as ionocytes, as well as in acinar cells. Isolated human parotid acinar cells exhibited Cl- conductance consistent with CFTR activity. This marks the first documented evidence of functional CFTR expression in human salivary gland acinar cells.

DNA damage regulates alternative splicing through inhibition of RNA polymerase II elongation.

DNA damage induces apoptosis and many apoptotic genes are regulated via alternative splicing (AS), but little is known about the control mechanisms. Here we show that ultraviolet irradiation (UV) affects cotranscriptional AS in a p53-independent way, through the hyperphosphorylation of RNA polymerase II carboxy-terminal domain (CTD) and a subsequent inhibition of transcriptional elongation, estimated in vivo and in real time. Phosphomimetic CTD mutants not only display lower elongation but also duplicate the UV effect on AS. Consistently, nonphosphorylatable mutants prevent the UV effect. Apoptosis promoted by UV in cells lacking p53 is prevented when the change in AS of the apoptotic gene bcl-x is reverted, confirming the relevance of this mechanism. Splicing-sensitive microarrays revealed a significant overlap of the subsets of genes that have changed AS with UV and those that have reduced expression, suggesting that transcriptional coupling to AS is a key feature of the DNA-damage response.

Control of astrocytic Ca2+ signaling by nitric oxide-dependent S-nitrosylation of Ca2+ homeostasis modulator 1 channels.

BACKGROUND: Astrocytes Ca2+ signaling play a central role in the modulation of neuronal function. Activation of metabotropic glutamate receptors (mGluR) by glutamate released during an increase in synaptic activity triggers coordinated Ca2+ signals in astrocytes. Importantly, astrocytes express the Ca2+-dependent nitric oxide (NO)-synthetizing enzymes eNOS and nNOS, which might contribute to the Ca2+ signals by triggering Ca2+ influx or ATP release through the activation of connexin 43 (Cx43) hemichannels, pannexin-1 (Panx-1) channels or Ca2+ homeostasis modulator 1 (CALHM1) channels. Hence, we aim to evaluate the participation of NO in the astrocytic Ca2+ signaling initiated by stimulation of mGluR in primary cultures of astrocytes from rat brain cortex. RESULTS: Astrocytes were stimulated with glutamate or t-ACPD and NO-dependent changes in [Ca2+]i and ATP release were evaluated. In addition, the activity of Cx43 hemichannels, Panx-1 channels and CALHM1 channels was also analyzed. The expression of Cx43, Panx-1 and CALHM1 in astrocytes was confirmed by immunofluorescence analysis and both glutamate and t-ACPD induced NO-mediated activation of CALHM1 channels via direct S-nitrosylation, which was further confirmed by assessing CALHM1-mediated current using the two-electrode voltage clamp technique in Xenopus oocytes. Pharmacological blockade or siRNA-mediated inhibition of CALHM1 expression revealed that the opening of these channels provides a pathway for ATP release and the subsequent purinergic receptor-dependent activation of Cx43 hemichannels and Panx-1 channels, which further contributes to the astrocytic Ca2+ signaling. CONCLUSIONS: Our findings demonstrate that activation of CALHM1 channels through NO-mediated S-nitrosylation in astrocytes in vitro is critical for the generation of glutamate-initiated astrocytic Ca2+ signaling.

Environmental assessment of phosphogypsum: A comprehensive geochemical modeling and leaching behavior study.

Understanding the variations in the geochemical composition of phosphogypsum (PG) destined for storage or valorization is crucial for assessing the safety and operational efficacy of waste management. The present study aimed to investigate the environmental behavior of PG using different leaching tests and to evaluate its geochemical behavior using geochemical modeling. Regarding the chemical characterization, the PG samples were predominantly composed of Ca (23.03-23.35 wt%), S (17.65-17.71 wt%), and Si (0.75-0.82 wt%). Mineralogically, the PG samples were primarily composed of gypsum (94.2-95.9 wt%) and quartz (1.67-1.76 wt%). Moreover, the automated mineralogy revealed the presence of apatite, fluorine and malladrite phases. The overall findings of the leaching tests showed that PG could be considered as non-hazardous material according to US Environmental Protection Agency limitations. However, a high leachability of elements at a L/S of 2 under acidic conditions ([Ca] = 166.52-199.87 mg/L, [S] = 207.9-233.59 mg/L, [F] = 248.62-286.65 mg/L) is observed. The weathering cell test revealed a considerable cumulative concentration over 90 days indicating potential adverse effects on the nearby environment (S: 8000 mg/kg, F: 3000 mg/kg, P: 700 mg/kg). Based on these results, it could be estimated that the surface storage of PG could have a serious impact on the environment. In this context, a simulation model was developed based on weathering cell results showed encouraging results for treating PG leachate using CaO before its disposal. Additionally, PHREEQC was used to analyze the speciation of major elements and calculate mineral phase saturation indices in PG leaching solutions. The findings revealed pH-dependent speciation for Ca, S, P, and F. The study identified gypsum, anhydrite, and bassanite as the key phases governing the dissolution of these elements.

Tenofovir Disoproxil Fumarate/Emtricitabine and Baricitinib for Patients at High Risk of Severe Coronavirus Disease 2019: The PANCOVID Randomized Clinical Trial.

BACKGROUND: This study was designed to evaluate if patients with high risk for severe coronavirus disease 2019 (COVID-19) would benefit from treatment with tenofovir disoproxil fumarate/emtricitabine (TDF/FTC) followed by baricitinib in case of hypoxemia and systemic inflammation. METHODS: PANCOVID is an open-label, double-randomized, phase 3 pragmatic clinical trial including adults with symptomatic COVID-19 with ≥2 comorbidities or aged ≥60 years and was conducted between 10 October 2020 and 23 September 2021. In the first randomization, patients received TDF/FTC or no TDF/FTC. In the second randomization, patients with room air oxygen saturation <95% and at least 1 increased inflammatory biomarker received baricitinib plus dexamethasone or dexamethasone alone. The primary endpoint was 28-day mortality. Main secondary endpoint was 28-day disease progression or critical care unit admission or mortality. The trial was stopped before reaching planned sample size due to the decrease in the number of cases and a mortality rate substantially lower than expected. RESULTS: Of the 355 included participants, 97% were hospitalized at baseline. Overall, 28-day mortality was 3.1%. The 28-day mortality relative risk (RR) for participants treated with TDF/FTC was 1.76 (95% confidence interval [CI], .52-5.91; P = .379); it was 0.42 (95% CI, .11-1.59; P = .201) for those treated with baricitinib. The 28-day RR for the main secondary combined endpoint for participants treated with TDF/FTC was 0.95 (95% CI, .66-1.40; P = .774); it was 0.90 (95% CI, .61-1.33; P = .687) for those treated with baricitinib. CONCLUSIONS: Our results do not suggest a beneficial effect of TDF/FTC; nevertheless, they are compatible with the beneficial effect of baricitinib already established by other clinical trials. CLINICAL TRIALS REGISTRATION: EudraCT: 2020-001156-18.

Recommendations From the International Consensus Conference on Anemia Management in Surgical Patients (ICCAMS).

BACKGROUND: Perioperative anemia has been associated with increased risk of red blood cell transfusion and increased morbidity and mortality after surgery. The optimal approach to the diagnosis and management of perioperative anemia is not fully established. OBJECTIVE: To develop consensus recommendations for anemia management in surgical patients. METHODS: An international expert panel reviewed the current evidence and developed recommendations using modified RAND Delphi methodology. RESULTS: The panel recommends that all patients except those undergoing minor procedures be screened for anemia before surgery. Appropriate therapy for anemia should be guided by an accurate diagnosis of the etiology. The need to proceed with surgery in some patients with anemia is expected to persist. However, early identification and effective treatment of anemia has the potential to reduce the risks associated with surgery and improve clinical outcomes. As with preoperative anemia, postoperative anemia should be treated in the perioperative period. CONCLUSIONS: Early identification and effective treatment of anemia has the potential to improve clinical outcomes in surgical patients.

Serial co-expression analysis of host factors from SARS-CoV viruses highly converges with former high-throughput screenings and proposes key regulators.

The current genomics era is bringing an unprecedented growth in the amount of gene expression data, only comparable to the exponential growth of sequences in databases during the last decades. This data allow the design of secondary analyses that take advantage of this information to create new knowledge. One of these feasible analyses is the evaluation of the expression level for a gene through a series of different conditions or cell types. Based on this idea, we have developed Automatic and Serial Analysis of CO-expression, which performs expression profiles for a given gene along hundreds of heterogeneous and normalized transcriptomics experiments and discover other genes that show either a similar or an inverse behavior. It might help to discover co-regulated genes, and common transcriptional regulators in any biological model. The present severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic is an opportunity to test this novel approach due to the wealth of data that are being generated, which could be used for validating results. Thus, we have identified 35 host factors in the literature putatively involved in the infectious cycle of SARS-CoV viruses and searched for genes tightly co-expressed with them. We have found 1899 co-expressed genes whose assigned functions are strongly related to viral cycles. Moreover, this set of genes heavily overlaps with those identified by former laboratory high-throughput screenings (with P-value near 0). Our results reveal a series of common regulators, involved in immune and inflammatory responses that might be key virus targets to induce the coordinated expression of SARS-CoV-2 host factors.

Nailfold videocapillaroscopy patterns in systemic sclerosis: implications for cutaneous subsets, disease features and prognostic value for survival.

OBJECTIVES: To assess the associations and prognostic value of scleroderma patterns by nailfold videocapillaroscopy (NVC) in patients with systemic sclerosis (SSc) and cutaneous subsets. METHODS: At baseline, 1356 SSc patients from the RESCLE registry were compared according to the scleroderma pattern as Late pattern and non-Late pattern, which included Early and Active patterns. Patient characteristics, disease features, survival time and causes of death were analysed. RESULTS: Late pattern was identified in 540 (39.8%), and non-Late pattern in 816 (60.2%) patients (88% women; 987 lcSSc/251 dcSSc). Late pattern was associated to dcSSc (OR=1.96; p<0.001), interstitial lung disease (ILD) (OR=1.29; p=0.031), and scleroderma renal crisis (OR=3.46; p<0.001). Once the cutaneous subset was disregarded in an alternative analysis, both digital ulcers (DU) (OR=1.29; p<0.037) and anti-topoisomerase I antibodies (OR=1.39; p< 0.036) emerged associated with the Late pattern. By cutaneous subsets, associations with Late pattern were: (1) in dcSSc, acro-osteolysis (OR=2.13; p=0.022), and systolic pulmonary artery pressure >40 mmHg by Doppler echocardiogram (OR=2.24; p<0.001); and (2) in lcSSc, ILD (OR=1.38; p=0.028). Survival was reduced in dcSSc with Late pattern compared to non-Late pattern (p=0.049). Risk factors for SSc mortality in multivariate regression Cox analysis were age at diagnosis (HR=1.03; p<0.001), dcSSc (HR=2.48; p<0.001), DU (HR=1.38; p=0.046), ILD (HR=2.81; p<0.001), and pulmonary arterial hypertension (HR=1.99; p<0.001). CONCLUSIONS: SSc patients with Late pattern more frequently present dcSSc and develop more fibrotic and vascular manifestations. Advanced microangiopathy by NVC identifies dcSSc patients at risk of reduced survival due to SSc-related causes.

Molecular diagnostic approaches for SARS-CoV-2 detection and pathophysiological consequences.

SARS-CoV-2, a novel coronavirus within the Coronaviridae family, is the causative agent behind the respiratory ailment referred to as COVID-19. Operating on a global scale, COVID-19 has led to a substantial number of fatalities, exerting profound effects on both public health and the global economy. The most frequently reported symptoms encompass fever, cough, muscle or body aches, loss of taste or smell, headaches, and fatigue. Furthermore, a subset of individuals may manifest more severe symptoms, including those consistent with viral pneumonitis, which can be so profound as to result in fatalities. Consequently, this situation has spurred the rapid advancement of disease diagnostic technologies worldwide. Predominantly employed in diagnosing COVID-19, the real-time quantitative reverse transcription PCR has been the foremost diagnostic method, effectively detecting SARS-CoV-2 viral RNA. As the pandemic has evolved, antigen and serological tests have emerged as valuable diagnostic tools. Antigen tests pinpoint specific viral proteins of SARS-CoV-2, offering swift results, while serological tests identify the presence of antibodies in blood samples. Additionally, there have been notable strides in sample collection methods, notably with the introduction of saliva-based tests, presenting a non-invasive substitute to nasopharyngeal swabs. Given the ongoing mutations in SARS-CoV-2, there has been a continuous need for genomic surveillance, encompassing full genome sequencing and the identification of new variants through Illumina technology and, more recently, nanopore metagenomic sequencing (SMTN). Consequently, while diagnostic testing methods for COVID-19 have experienced remarkable progress, no test is flawless, and there exist limitations with each technique, including sensitivity, specificity, sample collection, and the minimum viral load necessary for accurate detection. These aspects are comprehensively addressed within this current review.

Penny-wise and pound-foolish: the challenges of preoperative anaemia management.

The timely correction of anaemia before major surgery is important for optimising perioperative patient outcomes. However, multiple barriers have precluded the global expansion of preoperative anaemia treatment programmes, including misconceptions about the true cost/benefit ratio for patient care and health system economics. Institutional investment and buy-in from stakeholders could lead to significant cost savings through avoided complications of anaemia and red blood cell transfusions, and through containment of direct and variable costs of blood bank laboratories. In some health systems, billing for iron infusions could generate revenue and promote growth of treatment programmes. The aim of this work is to galvanise integrated health systems worldwide to diagnose and treat anaemia before major surgery.

FT-Raman Methodology Applied to Study the Effect of Time and Type of Seasoning in the Crafting of Sherry Casks® Used in the Aging of Brandy De Jerez.

Brandy de Jerez is a grape-derived spirit produced in Southern Spain with specific characteristics that come from the casks where it is produced, which must have previously contained some type of Sherry wine for at least 12 months. These casks are known as Sherry Cask®. In this work, Brandies de Jerez aged for different aging times (0, 3, 6 and 12 months) in casks seasoned with three different types of Sherry wines (Fino, Oloroso and Amontillado) have been studied. The samples have been analyzed using FT-Raman spectroscopy, and their chemical characterization has also been realized by studying their total content of organic acid, volatile compounds, and phenolic and furanic compounds. Their chemical study showed that the main differences between the studied samples were due to the duration and the type of seasoning performed. However, the spectra obtained through FT-Raman presented noticeable differences according to cask seasoning time and the Sherry wine used for the process. A PCA (Principal Component Analysis) confirmed that the Brandies de Jerez presented significant differences depending on the seasoning time and type that the casks were subjected to. A PLS-R (Partial Least Squares Regression) study enabled establishing a close correlation between specific regions of the FT-Raman spectra and cask seasoning time.

A Functional Pipeline of Genome-Wide Association Data Leads to Midostaurin as a Repurposed Drug for Alzheimer's Disease.

Genome-wide association studies (GWAS) constitute a powerful tool to identify the different biochemical pathways associated with disease. This knowledge can be used to prioritize drugs targeting these routes, paving the road to clinical application. Here, we describe DAGGER (Drug Repositioning by Analysis of GWAS and Gene Expression in R), a straightforward pipeline to find currently approved drugs with repurposing potential. As a proof of concept, we analyzed a meta-GWAS of 1.6 × 107 single-nucleotide polymorphisms performed on Alzheimer's disease (AD). Our pipeline uses the Genotype-Tissue Expression (GTEx) and Drug Gene Interaction (DGI) databases for a rational prioritization of 22 druggable targets. Next, we performed a two-stage in vivo functional assay. We used a C. elegans humanized model over-expressing the Aß1-42 peptide. We assayed the five top-scoring candidate drugs, finding midostaurin, a multitarget protein kinase inhibitor, to be a protective drug. Next, 3xTg AD transgenic mice were used for a final evaluation of midostaurin's effect. Behavioral testing after three weeks of 20 mg/kg intraperitoneal treatment revealed a significant improvement in behavior, including locomotion, anxiety-like behavior, and new-place recognition. Altogether, we consider that our pipeline might be a useful tool for drug repurposing in complex diseases.

Use of gonadotropins in ovarian stimulation in Spain: Delphi consensus.

Two-round Delphi study carried out in Spain. Three theme-based blocks were set out: 1) Patient profiles: therapeutic goal and parameters to be analysed according to POSEIDON patient profiles; 2) Ovarian stimulation protocols with antagonists: monotherapy (FSH) vs combined therapy (FSH + LH/HMG); 3) Safety and effectiveness of the devices. The antral follicle count and the anti-Müllerian hormone level were considered indicators that can be used to predict ovarian response. More than 80% of the participants agreed that FSH monotherapy is the recommended regimen in normal/hyper-responsive patients of < 35 years of age; that 150-300 IU is the dose to be used in ovarian stimulation in monotherapy depending on clinical parameters; and that FSH monotherapy improves patients' comfort compared to two combined drugs. It was unanimously considered that the type of device used by the patient influences the comfort of the treatment.IMPACT STATEMENTWhat is already known on this subject? There is currently no consensus on the optimal treatment for controlled ovarian stimulation for patients undergoing IVF which leads to highly variable clinical practices.What the results of this study add? This study's strong point is that, since it is a consensus, it has been possible to include more topics than would normally be dealt with in a systematic review or guidelines, which are generally based on a strict method that restricts the scope of the research. Experts have reached a consensus on most of the statements and based on these they have issued consensus statements that will enable the optimal use of gonadotropins in IVF.What the implications are of these findings for clinical practice and/or further research? This Delphi consensus provides a real-life clinical perspective on gonadotropin usage in IVF.

Composition and Flowering Quality of Cacahuacintle Maize Populations from the High Valleys of Mexico.

Cacahuacintle is one of the maize types with great demand for pozole preparation; however, little is known about the variation in chemical composition and flowered grain quality among populations. Physicochemical characteristics, flowered grain quality, pasting properties, and starch microstructure were evaluated in 33 populations of Cacahuacintle maize collected in Valles Altos, Mexico. The seeds samples of corn were obtained in 2017 from local farmers in the states of Mexico, Puebla, and Tlaxcala. Results were analyzed under a completely randomized design, and the ANOVA, Tukey test, and principal components were obtained. The ANOVA showed significance (p ≤ 0.05) in 18 of the 22 variables evaluated. The TE-6, AM-7, and CA-6 populations were outstanding for the good quality of their protein, pasting viscosity, and flowered grain quality. Nine populations collected in Calimaya, estate of Mexico, and Serdan Valley, state of Puebla, presented excellent physical, pasting, and flowery grain characteristics, with reduced protein content and lysine and tryptophan values typical of maize with normal endosperm. The softness of the endosperm grain, starch microstructural, and pasting characteristics of Cacahuacintle maize populations have a fundamental role in reducing the time and increasing the flowered grain volume, properties that were different from those observed in the Chalqueño, included as dent maize check. Variations in grain quality among Cacahuacintle maize populations is an important genetic resource for the improvement of the nutritional and flowering quality of Cacahuacintle maize.

ORFLine: a bioinformatic pipeline to prioritize small open reading frames identifies candidate secreted small proteins from lymphocytes.

MOTIVATION: The annotation of small open reading frames (smORFs) of <100 codons (<300 nucleotides) is challenging due to the large number of such sequences in the genome. RESULTS: In this study, we developed a computational pipeline, which we have named ORFLine, that stringently identifies smORFs and classifies them according to their position within transcripts. We identified a total of 5744 unique smORFs in datasets from mouse B and T lymphocytes and systematically characterized them using ORFLine. We further searched smORFs for the presence of a signal peptide, which predicted known secreted chemokines as well as novel micropeptides. Four novel micropeptides show evidence of secretion and are therefore candidate mediators of immunoregulatory functions. AVAILABILITY AND IMPLEMENTATION: Freely available on the web at https://github.com/boboppie/ORFLine. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.

Early redox homeostasis disruption contributes to the differential cytotoxicity of imiquimod on transformed and normal endothelial cells.

The off-label use of imiquimod (IQ) for hemangioma treatment has shown clinical benefits. We have previously reported a selective direct IQ-cytotoxic effect on transformed (H5V) vs. normal (1G11) endothelial cells (EC). In the present study, we investigated the mechanism underlying this selective cytotoxicity in terms of TLR7/8 receptor expression, NF-κB signalling and time-dependent modifications of oxidative stress parameters (ROS: reactive oxygen species, catalase and superoxide dismutase activities, GSH/GSSG and lipid peroxidation). TLR7/8 level was extremely low in both cell lines, and IQ did not upregulate TLR7/8 expression or activate NF-κB signalling. IQ significantly induced ROS in H5V after 2 h and strongly affected antioxidant defenses. After 12 h, enzyme activities were restored to baseline levels but a robust drop in GSH/GSSG persisted together with increased lipid peroxidation levels and a marked mitochondrial dysfunction. Although in normal IQ-treated EC some oxidative stress parameters were affected after 4 h, mitochondrial health and GSH/GSSG ratio remained notably unaffected after 12 h. Therefore, the early alterations (0-2 h) in transformed EC breached redox homeostasis as strongly as to enhance their susceptibility to IQ. This interesting facet of IQ as redox disruptor could broaden its therapeutic potential for other skin malignancies, alone or in adjuvant schemes.