The role of oxidative stress on breast cancer development and therapy

Hypoxia induces ROS-resistant memory upon reoxygenation in vivo promoting metastasis in part via MUC1-C

Hypoxia occurs in 90% of solid tumors and is associated with metastasis and mortality. Breast cancer cells that experience intratumoral hypoxia are 5x more likely to develop lung metastasis in animal models. Using spatial transcriptomics, we determine that hypoxic cells localized in more oxygenated tumor regions (termed 'post-hypoxic') retain expression of hypoxia-inducible and NF-kB-regulated genes, even in the oxygen-rich bloodstream. This cellular response is reproduced in vitro under chronic hypoxic conditions followed by reoxygenation. A subset of genes remains increased in reoxygenated cells. MUC1/MUC1-C is upregulated by both HIF-1α and NF-kB-p65 during chronic hypoxia. Abrogating MUC1 decreases the expression of superoxide dismutase enzymes, causing reactive oxygen species (ROS) production and cell death. A hypoxia-dependent genetic deletion of MUC1, or MUC1-C inhibition by GO-203, increases ROS levels in circulating tumor cells (CTCs), reducing the extent of metastasis. High MUC1 expression in tumor biopsies is associated with recurrence, and MUC1+ CTCs have lower ROS levels than MUC1- CTCs in patient-derived xenograft models. This study demonstrates that therapeutically targeting MUC1-C reduces hypoxia-driven metastasis.

Examining Hemin and its Derivatives: Induction of Heme-Oxygenase-1 Activity and Oxidative Stress in Breast Cancer Cells through Collaborative Experimental Analysis and Molecular Dynamics Simulations

Hemin triggers intracellular reactive oxygen species (ROS) accumulation and enhances heme oxygenase-1 (HOX-1) activity, indicating its potential as an anticancer agent, though precise control of its intracellular levels is crucial. The study explores the impact of hemin and its derivatives, hemin-tyrosine, and hemin-styrene (H-Styr) conjugates on migration, HOX-1 expression, specific apoptosis markers, mitochondrial functions, and ROS generation in breast cancer cells. Molecular docking and dynamics simulations were used to understand the interactions among HOX-1, heme, and the compounds. Hemin outperforms its derivatives in inducing HOX-1 expression, exhibiting pro-oxidative effects and reducing cell migration. Molecular simulations show that heme binds favorably to HOX-1, followed by the other compounds, primarily through van der Waals and electrostatic forces. However, only van der Waals forces determine the H-Styr complexation. These interactions, influenced by metalloporphyrin characteristics, provide insights into HOX-1 regulation and ROS generation, potentially guiding the development of breast cancer therapies targeting oxidative stress.

High Levels of Superoxide Dismutase 2 Are Associated With Worse Prognosis in Patients With Breast Cancer

OBJECTIVE

Breast cancer is classified based on hormone receptor status and human epidermal growth factor receptor 2 (HER2) expression, including luminal, HER2+, or triple-negative (TNBC). The absence of a therapeutic target in TNBC and the resistance to treatment associated with other subtypes means that research for new biomarkers remains important. In this context, superoxide dismutase 2 (SOD2) has emerged as a potential therapeutic target due to its clinicopathological associations and its ability to predict responses in human tumors. To analyze SOD2 staining in samples obtained from individuals with breast cancer and explore its transcriptional pattern across tumor subtypes.

MATERIALS AND METHODS

SOD2 staining was assessed using the immunohistochemistry (IHC) in 80 samples from breast cancer patients. To analyze the expression profile at the transcriptional level, international databases such as cBioPortal (1,980 patients) and PrognoScan were accessed.

RESULTS

Significant differences were observed between SOD2 expression analyzed by IHC, and estrogen (p = 0.0008) and progesterone (p = 0.0003) receptors, as well as tumor subtypes (p<0.0001). These differences were found in conjunction with other associations, including clinical and pathological data, such as tumor stage (p = 0.0129), tumor size (p = 0.0296), and node metastasis (p = 0.0486). Moreover, elevated SOD2 expression correlated with an unfavorable prognosis. The in silico analysis revealed a similar pattern, despite operating at the transcriptional level. Moreover, notable correlations were identified between elevated SOD2 expression and worse survival.

CONCLUSION

These results highlight the importance of SOD2 in breast cancer, particularly in aggressive subtypes. Increased SOD2 staining correlates with poorer outcomes, suggesting it as a potential therapeutic target.

Coordinated inflammation and immune response transcriptional regulation in breast cancer molecular subtypes

Breast cancer, characterized by its complexity and diversity, presents significant challenges in understanding its underlying biology. In this study, we employed gene co-expression network analysis to investigate the gene composition and functional patterns in breast cancer subtypes and normal breast tissue. Our objective was to elucidate the detailed immunological features distinguishing these tumors at the transcriptional level and to explore their implications for diagnosis and treatment. The analysis identified nine distinct gene module clusters, each representing unique transcriptional signatures within breast cancer subtypes and normal tissue. Interestingly, while some clusters exhibited high similarity in gene composition between normal tissue and certain subtypes, others showed lower similarity and shared traits. These clusters provided insights into the immune responses within breast cancer subtypes, revealing diverse immunological functions, including innate and adaptive immune responses. Our findings contribute to a deeper understanding of the molecular mechanisms underlying breast cancer subtypes and highlight their unique characteristics. The immunological signatures identified in this study hold potential implications for diagnostic and therapeutic strategies. Additionally, the network-based approach introduced herein presents a valuable framework for understanding the complexities of other diseases and elucidating their underlying biology.

Exploring the broad-spectrum pharmacological activity of two less studied Australian native fruits: chemical characterisation using LCMS-driven metabolomics

Australian fruits such as native currant (Acrotriche depressa) and lemon aspen (Acronychia acidula) are under-examined in terms of their therapeutic potential. In this study, the in vitro antiproliferative activity of native currant and lemon aspen extracts (water and ethanol) against MCF7 breast adenocarcinoma cells was determined using the Alamar blue assay. The most potent extracts (native currant water, NC-W; native currant ethanol, NC-Et; lemon aspen ethanol, LA-Et) were further evaluated using flow cytometry to detect the potential induction of apoptosis in MCF7 cells whereas 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) assay was implemented to understand the impact of the extracts on the intracellular reactive oxygen species (ROS) levels in MCF7 cells. Furthermore, the antioxidant activity of the extracts was assessed using ABTS [2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate)], and CUPRAC (cupric reducing antioxidant capacity) assays. The antimicrobial susceptibility testing of NC-W, NC-Et, and LA-Et was carried out against Gram-positive (Staphylococcus aureus), Gram-negative (Escherichia coli), and yeast (Candida albicans) strains using a resazurin-based assay. Additionally, potential metabolites in the NC-W and NC-Et extracts were analysed with liquid chromatography-mass spectrometry (LC-MS) driven metabolomics and chemometrics to spot differential and major metabolites. A dose-dependent antiproliferative activity was conferred by the NC extracts against MCF7 cells. Of the two LA extracts, only LA-Et showed a dose-dependent antiproliferative activity at higher concentrations. Both NC extracts and LA-Et induced apoptosis in MCF7 cells. None of the extracts increased the production of ROS significantly in MCF7 cells compared to the untreated control. A dose-dependent antioxidant activity was observed in both antioxidant assays. Both NC and LA extracts showed a similar minimum inhibitory concentration (MIC) value against S. aureus. Only LA-Et showed activity against E. coli, while NC-W and NC-Et were less active. All extracts showed MIC values of >1500 μg mL-1 against C. albicans. The metabolomics analysis revealed an abundance of flavonoids, fatty acyl derivatives, carbohydrates, carboxylic acids and their derivatives, and alkaloid compounds as potential bioactive metabolites in the NC extracts. In conclusion, both NC and LA showed antiproliferative (against MCF7 breast adenocarcinoma cells through the induction of apoptosis), strong antioxidant and minimal antimicrobial properties.

Oxidative Stress in Breast Cancer: A Biochemical Map of Reactive Oxygen Species Production

This review systematizes information about the metabolic features of breast cancer directly related to oxidative stress. It has been shown those redox changes occur at all levels and affect many regulatory systems in the human body. The features of the biochemical processes occurring in breast cancer are described, ranging from nonspecific, at first glance, and strictly biochemical to hormone-induced reactions, genetic and epigenetic regulation, which allows for a broader and deeper understanding of the principles of oncogenesis, as well as maintaining the viability of cancer cells in the mammary gland. Specific pathways of the activation of oxidative stress have been studied as a response to the overproduction of stress hormones and estrogens, and specific ways to reduce its negative impact have been described. The diversity of participants that trigger redox reactions from different sides is considered more fully: glycolytic activity in breast cancer, and the nature of consumption of amino acids and metals. The role of metals in oxidative stress is discussed in detail. They can act as both co-factors and direct participants in oxidative stress, since they are either a trigger mechanism for lipid peroxidation or capable of activating signaling pathways that affect tumorigenesis. Special attention has been paid to the genetic and epigenetic regulation of breast tumors. A complex cascade of mechanisms of epigenetic regulation is explained, which made it possible to reconsider the existing opinion about the triggers and pathways for launching the oncological process, the survival of cancer cells and their ability to localize.

Systemic DNA Damage and Repair Activity Vary by Race in Breast Cancer Survivors

Non-Hispanic Black breast cancer survivors have poorer outcomes and higher mortality rates than White survivors, but systemic biological mechanisms underlying these disparities are unclear. We used circulating leukocytes as a surrogate for measuring systemic mechanisms, which might be different from processes in the target tissue (e.g., breast). We investigated race-based differences in DNA damage and repair, using a novel CometChip assay, in circulating leukocytes from breast cancer survivors who had completed primary cancer therapy and were cancer free. We observed novel race-based differences in systemic DNA damage and repair activity in cancer survivors, but not in cells from healthy volunteers. Basal DNA damage in leukocytes was higher in White survivors, but Black survivors showed a much higher induction after bleomycin treatment. Double-strand break repair activity was also significantly different between the races, with cells from White survivors showing more sustained repair activity compared to Black leukocytes. These results suggest that cancer and cancer therapy might have long-lasting effects on systemic DNA damage and repair mechanisms that differ in White survivors and Black survivors. Findings from our preliminary study in non-cancer cells (circulating leukocytes) suggest systemic effects beyond the target site, with implications for accelerated aging-related cancer survivorship disparities.

NOX4 alleviates breast cancer cell aggressiveness by co-ordinating mitochondrial turnover through PGC1α/Drp1 axis

Triple Negative Breast Cancer (TNBC) is a highly aggressive form of breast cancer, with few treatment options. This study investigates the complex molecular mechanism by which NADPH oxidase 4 (NOX4), a major ROS producer in mitochondria, affects the aggressiveness of luminal and triple-negative breast cancer cells (TNBCs). We found that NOX4 expression was differentially regulated in luminal and TNBC cells, with a positive correlation to their epithelial characteristics. Time dependent analysis revealed that TNBCs exhibits higher steady-state ROS levels than luminal cells, but NOX4 silencing increased ROS levels in luminal breast cancer cells and enhanced their ability to migrate and invade. In contrast, NOX4 over expression in TNBCs had the opposite effect. The mouse tail-vein experiment showed that the group injected with NOX4 silenced luminal cells had a higher number of lung metastases compared to the control group. Mechanistically, NOX4 enhanced PGC1α dependent mitochondrial biogenesis and attenuated Drp1-mediated mitochondrial fission in luminal breast cancer cells, leading to an increased mitochondrial mass and elongated mitochondrial morphology. Interestingly, NOX4 silencing increased mitochondrial ROS (mtROS) levels without affecting mitochondrial (Δψm) and cellular integrity. Inhibition of Drp1-dependent fission with Mdivi1 reversed the effect of NOX4-dependent mitochondrial biogenesis, dynamics, and migration of breast cancer cells. Our findings suggest that NOX4 expression diminishes from luminal to a triple negative state, accompanied by elevated ROS levels, which may modulate mitochondrial turnover to attain an aggressive phenotype. The study provides potential insights for targeted therapies for TNBCs.

Proguanil Suppresses Breast Tumor Growth In Vitro and In Vivo by Inducing Apoptosis via Mitochondrial Dysfunction

Breast cancer, ranking as the second leading cause of female cancer-related deaths in the U.S., demands the exploration of innovative treatments. Repurposing FDA-approved drugs emerges as an expedited and cost-effective strategy. Our study centered on proguanil, an antimalarial drug, reveals notable anti-proliferative effects on diverse breast cancer cell lines, including those derived from patients. Proguanil-induced apoptosis was associated with a substantial increase in reactive oxygen species (ROS) production, leading to reduced mitochondrial membrane potential, respiration, and ATP production. Proguanil treatment upregulated apoptotic markers (Bax, p-H2AX, cleaved-caspase 3, 9, cleaved PARP) and downregulated anti-apoptotic proteins (bcl-2, survivin) in breast cancer cell lines. In female Balb/c mice implanted with 4T1 breast tumors, daily oral administration of 20 mg/kg proguanil suppressed tumor enlargement by 55%. Western blot analyses of proguanil-treated tumors supported the in vitro findings, demonstrating increased levels of p-H2AX, Bax, c-PARP, and c-caspase3 as compared to controls. Our results collectively highlight proguanil's anticancer efficacy in vitro and in vivo in breast cancer, prompting further consideration for clinical investigations.

Impact of Radiation Therapy on Serum Humanin and MOTS-c Levels in Patients with Lung or Breast Cancer

BACKGROUND

Lung and breast cancer are the most frequent causes of death from cancer globally. The objectives of this research were to evaluate the serum mitochondrial open reading frame of the 12S rRNA-c (MOTS-c) and humanin levels in lung or breast cancer patients, and investigate the impacts of radiation therapy on the circulating levels of these peptides.

METHODS

35 lung cancer patients, 34 breast cancer patients, and healthy volunteers as a control group were recruited in this prospective observatory research. Lung cancer patients with stage IIIA/IIIB were treated with paclitaxel-based chemotherapy plus radiotherapy (2 Gy per day, 30 times, 60 Gy total dose). Breast cancer stage IIA/IIB patients were treated with postoperative locoregional radiation therapy (2 Gy per day, 25 times, 50 Gy total dose). The ELISA method was used to detect serum humanin and MOTS-c levels during, before, and after radiotherapy.

RESULTS

We observed marked elevations in circulating MOTS-c, but not humanin levels in patients with lung cancer (P < 0.001). Radiation therapy led to a marked augmentation in MOTS-c levels in these patients (P < 0.001). On the other hand, there was a marked decline in humanin, but not MOTS-c, levels in breast cancer patients (P < 0.001).

CONCLUSION

Our research has shown, for the first time, that increased MOTS-c and decreased humanin levels play a role in lung cancer and breast cancer, respectively. Additionally, radiotherapy modifies MOTS-c levels in patients with lung, but not breast cancer.

N-acetyl-l-tryptophan (NAT) ameliorates radiation-induced cell death in murine macrophages J774A.1 via regulating redox homeostasis and mitochondrial dysfunction

Ionizing radiation interacts with the immune system and induces molecular damage in the cellular milieu by generating reactive oxygen species (ROS) leading to cell death. The present study was performed to investigate the protective efficacy of N-acetyl-L-tryptophan (NAT) against gamma-radiation-induced cell death in murine macrophage J774A.1 cells. The radioprotective efficacy of NAT was evaluated in terms of cell survivability, effect on antioxidant enzyme activity, and free radicals inhibition. Radioprotective efficacy of NAT pretreatment to irradiated cells was assessed via cell cycle progression, mitochondrial membrane potential (MMP) perturbation, and apoptosis regulation using flow cytometry. Results of the study demonstrated significant radioprotective efficacy (>80%) of NAT in irradiated cells as estimated by sulforhodamine B (SRB), MTT, and clonogenic assay. Significant (p < 0.001) reduction in ROS, xanthine oxidase, and mitochondrial superoxide levels along with increment in catalase, glutathione-s-transferase, glutathione, and ATPase activities in NAT pretreated plus irradiated cells was observed as compared to the gamma-irradiated cells. Further, significant (p < 0.001) stabilization of MMP and reduction in apoptosis was also observed in NAT pretreated plus irradiated cells as compared to irradiated cells that not pretreated with NAT. The current study demonstrates that NAT pretreatment to irradiated cells protects against gamma radiation-induced cell death by reducing oxidative stress, stabilizing MMP, and inhibiting apoptosis. These observations conclusively highlight the potential of developing NAT as a prospective radioprotective agent upon further validation using in-depth preclinical assessment in cellular and animal models.

Discovery of a synthetic taiwaniaquinoid with potent in vitro and in vivo antitumor activity against breast cancer cells

Taiwaniaquinoids are a unique family of diterpenoids predominantly isolated from Taiwania cryptomerioides Hayata. Previously, we evaluated the antiproliferative effect of several synthetic taiwaniaquinoids against human lung (A-549), colon (T-84), and breast (MCF-7) tumor cell lines. Herein, we report the in vitro and in vivo antitumor activity of the most potent compounds. Their cytotoxic activity against healthy peripheral blood mononuclear cells (PBMCs) has also been examined. We underscore the limited toxicity of compound C36 in PBMCs and demonstrate that it exerts its antitumor effect in MCF-7 cells (IC50 = 1.8 µM) by triggering an increase in reactive oxygen species, increasing the cell population in the sub-G1 phase of the cell cycle (90 %), and ultimately activating apoptotic (49.6 %) rather than autophagic processes. Western blot results suggested that the underlying mechanism of the C36 apoptotic effects was linked to caspase 9 activation and a rise in the Bax/Bcl-2 ratio. In vivo analyses showed normal behavior and hematological parameters in C57BL/6 mice post C36 treatment. Moreover, no significant impact was observed on the biochemical parameters of these animals, indicating that C36 did not induce liver toxicity. Furthermore, C36 demonstrated a significant reduction in tumor growth in immune-competent C57BL/6 mice implanted with E0771 mouse mammary tumor cells, effectively improving survival rates. These findings position taiwaniaquinoids, particularly compound C36, as promising therapeutic candidates for human breast cancer.

Gut microbiota metabolites, redox status, and the related regulatory effects of probiotics

Oxidative stress is a state of imbalance between oxidation and antioxidation. It is caused by excess levels of free radicals and leads to the damage of DNA, proteins, and lipids. The crucial role of gut microbiota in regulating oxidative stress has been widely demonstrated. Studies have suggested that the redox regulatory effects of gut microbiota are related to gut microbiota metabolites, including fatty acids, lipopolysaccharides, tryptophan metabolites, trimethylamine-N-oxide and polyphenolic metabolites. In recent years, the potential benefits of probiotics have been gaining increasing scientific interest owing to their ability to modulate gut microbiota and oxidative stress. In this review, we summarise the adverse health effects of oxidative stress and discuss the role of the gut microbiota and its metabolites in redox regulation. Based on the influence of gut microbiota metabolites, the roles of probiotics in preventing oxidative stress are highlighted.

MitoQ combats tumor cell progression in Ehrlich ascites carcinoma mice: A crosstalk between mitochondrial oxidative status, mitophagy, and NF-κB signaling

Despite the clinical advances in cancer treatment, the high mortality rate is still a great challenge, requiring much effort to find new and efficient cancer therapies.

AIMS

The present evidence investigated the potential antiproliferative impact of the mitochondrial-targeted antioxidant, Mitoquinol (MitoQ), on a mouse model of Ehrlich ascites carcinoma (EAC).

MAIN METHODS

Mice-bearing tumors were administered two doses of MitoQ (0.3 mg & 0.5 mg/kg; i.p daily) or doxorubicin (2 mg/kg; i.p daily) for 20 days.

KEY FINDINGS

EAC mice revealed exacerbated mitochondrial reactive oxygen species (mtROS) and impaired mitochondrial membrane potential (△Ψm). Dysfunctional mitophagy was observed in EAC mice, along with boosting aerobic glycolysis. In addition, tumor cells exhibited higher proliferation rates, thereby stimulating cell cycle, invasion, and angiogenesis biomarkers together with suppressing proapoptotic proteins, events that might be correlated with activation of NF-κB signaling. The administration of MitoQ combated tumor cell survival and dissemination in EAC mice as evidenced by reducing tumor volumes and weights and increasing the number of necrotic areas in histopathological assessment. MitoQ also repressed tumor cell cycle, invasion, and angiogenesis via preventing cyclin D1 mRNA, MMP-1, and CD34 levels as well as VEGF protein expression. These observations were associated with the abrogation of mtROS overproduction and enhancement of the mitophagy proteins, PINK1/Parkin levels, followed by inhibition of NADH dehydrogenase. Notably, NF-κB signaling was modulated.

SIGNIFICANCE

This study suggests that MitoQ combated tumor cell survival and progression in EAC mice by maintaining mtROS and restoring mitophagy, thereby attenuation of NF-κB activation.

Moringa oleifera: A Review on the Antiproliferative Potential in Breast Cancer Cells

The global burden of female breast cancer and associated deaths has become a major concern. Many chemotherapeutic agents, such as doxorubicin, have been shown to have adverse side effects. The development of multi-drug resistance is a common occurrence, contributing to chemotherapeutic failure. The resistance of breast cancer cells to drug treatment leads to a decline in the treatment efficacy and an increase in cancer recurrence. Therefore, action is required to produce alternative drug therapies, such as herbal drugs. Herbal drugs have been proven to be beneficial in treating illnesses, including cancer. This review aims to highlight the antiproliferative potential of Moringa oleifera (MO), a medicinal tree native to India and indigenous to Africa, in breast cancer cells. Although MO is not yet considered a commercial chemopreventive drug, previous studies have indicated that it could become a chemotherapeutic agent. The possible antiproliferative potential of MO aqueous leaf extract has been previously proven through its antioxidant potential as well as its ability to induce apoptosis. This review will provide an increased understanding of the effect that MO aqueous leaf extract could potentially have against breast cancer.

Nano Uncaria gambir as Chemopreventive Agent Against Breast Cancer

BACKGROUND

Breast cancer is one of the main causes of death in women. Uncaria gambir is an Indonesian herbal plant that can be used as an anti-cancer. However, herbal medicines have low bioavailability, which affects their bioactivity. Nanoencapsulation can increase bioavailability and stability of bioactive compounds in herbal medicines.

PURPOSE

This recent finding tried to unravel anti-cancer and chemopreventive of U. gambir nano-encapsulated by Na-alginate.

STUDY DESIGN

U. gambir bioactive compounds were isolated and characterized using UV-Vis spectrometer, FTIR, NMR and HR-MS. U. gambir extract was nanoencapsulated using Na-alginate. Anti-cancer effect was assessed by MTT assay towards T47D cell. Meanwhile, a chemopreventive analysis was carried out in breast cancer mice-induced benzo[α]pyrene. The healthy mice were divided into 8 groups comprising control and treatment.

RESULTS

Elucidation of U. gambir ethyl acetate extract confirmed high catechin content, 89.34% (w/w). Successful nanoencapsulation of U. gambir (G-NPs) was indicated. The particle size of G-NPs was 78.40 ± 12.25 nm. Loading efficiency (LE) and loading amount (LA) of G-NPs were 97.56 ± 0.04% and 32.52 ± 0.01%, respectively. G-NPs had an EC50 value of 10.39 ± 3.50 µg/mL, which was more toxic than the EC50 value of extract towards the T47D cell line. Administration of 200 mg/kg BW G-NPs to mice induced by benzo[α]pyrene exhibited SOD and GSH levels of 13.69 ng/mL and 455.6 ng/mL. In addition, the lowest TNF-α level was 27.96 ng/mL. A dose of 100 mg/kg BW G-NPs could best increase CAT levels by 7.18 ng/mL. There was no damage or histological abnormalities found in histological analysis of the breast tissue in the group given 200 mg/kg BW G-NPs.

Engineered vitamin E-tethered non-immunogenic facial lipopeptide for developing improved siRNA based combination therapy against metastatic breast cancer

RNA interference based therapeutic gene silencing is an emerging platform for managing highly metastatic breast cancer. Cytosolic delivery of functional siRNA remains the key obstacle for efficient RNAi therapy. To overcome the challenges of siRNA delivery, we have engineered a vitamin E-tethered, short, optimum protease stabilized facial lipopeptide based non-immunogenic, biocompatible siRNA transporter to facilitate the clinical translation in future. Our designed lipopeptide has an Arginine-Sarcosine-Arginine segment for providing optimum protease-stability, minimizing adjacent arginine-arginine repulsion and reducing intermolecular aggregation and α-tocopherol as the lipidic moiety for facilitating cellular permeabilization. Interestingly, our designed non-immunogenic siRNA transporter has exhibited significantly better long term transfection efficiency than HiPerFect and can transfect hard to transfect primary cell line, HUVEC. Our engineered siRNA therapeutics demonstrated high efficacy in managing metastasis against triple negative breast cancer by disrupting the crosstalk of endothelial cells and MDA-MB-231 and reduced stemness and metastatic markers, as evidenced by downregulating critical oncogenic pathways. Our study aimed at silencing Notch1 signalling to achieve "multi-targeted" therapy with a single putative molecular medicine. We have further developed mechanistically rational combination therapy combining Notch1 silencing with a repurposed drug m-TOR inhibitor, metformin, which demonstrated synergistic interaction and enhanced antitumor efficacy against cancer metastasis.

Association of Dietary Intake of Zinc and Selenium with Breast Cancer Risk: A Case-Control Study in Chinese Women

As major nonenzymatic antioxidant components in the body, dietary Zinc (Zn) and Selenium (Se) may have an impact on breast cancer development. This study aimed to investigate the relationship between dietary Zn, Se intake and breast cancer risk in Chinese women. The case-control study included 1591 cases and 1622 age-frequency matched controls. Dietary intake was collected using a validated food frequency questionnaire. Dietary Zn and Se were divided into four categories: Zn/Se from plants, Zn/Se from meat, Zn/Se from red meat, and Zn/Se from white meat. Unconditional logistic regression models and restricted cubic spline analyses were performed to identify potential associations. Zn from white meat intake was linearly and inversely associated with breast cancer risk, and Se from red meat intake was linearly and positively associated with breast cancer risk, with adjusted odds ratio and 95% confidence interval of 0.76 (0.61-0.95) and 1.36 (1.04-1.77), respectively. Non-linear relationships were found between total dietary Zn, Zn from meat, Zn from red meat intake and breast cancer risk (p_{non-linearity} < 0.05). In conclusion, dietary Zn and Se intake were associated with breast cancer risk in Chinese women, and the optimal intake of Zn may be beneficial for breast cancer prevention.

NNAT is a novel mediator of oxidative stress that suppresses ER + breast cancer

BACKGROUND

Neuronatin (NNAT) was recently identified as a novel mediator of estrogen receptor-positive (ER+) breast cancer cell proliferation and migration, which correlated with decreased tumorigenic potential and prolonged patient survival. However, despite these observations, the molecular and pathophysiological role(s) of NNAT in ER + breast cancer remains unclear. Based on high protein homology with phospholamban, we hypothesized that NNAT mediates the homeostasis of intracellular calcium [Ca2+]i levels and endoplasmic reticulum (EndoR) function, which is frequently disrupted in ER + breast cancer and other malignancies.

METHODS

To evaluate the role of NNAT on [Ca2+]i homeostasis, we used a combination of bioinformatics, gene expression and promoter activity assays, CRISPR gene manipulation, pharmacological tools and confocal imaging to characterize the association between ROS, NNAT and calcium signaling.

RESULTS

Our data indicate that NNAT localizes predominantly to EndoR and lysosome, and genetic manipulation of NNAT levels demonstrated that NNAT modulates [Ca2+]i influx and maintains Ca2+ homeostasis. Pharmacological inhibition of calcium channels revealed that NNAT regulates [Ca2+]i levels in breast cancer cells through the interaction with ORAI but not the TRPC signaling cascade. Furthermore, NNAT is transcriptionally regulated by NRF1, PPARα, and PPARγ and is strongly upregulated by oxidative stress via the ROS and PPAR signaling cascades.

CONCLUSION

Collectively, these data suggest that NNAT expression is mediated by oxidative stress and acts as a regulator of Ca2+ homeostasis to impact ER + breast cancer proliferation, thus providing a molecular link between the longstanding observation that is accumulating ROS and altered Ca2+ signaling are key oncogenic drivers of cancer.

Exploring the Multi-Faceted Potential of Carob (Ceratonia siliqua var. Rahma) Leaves from Morocco: A Comprehensive Analysis of Polyphenols Profile, Antimicrobial Activity, Cytotoxicity against Breast Cancer Cell Lines, and Genotoxicity

The botanical species Ceratonia siliqua L., commonly referred to as the Carob tree, and locally as "L'Kharrûb", holds significance as an agro-sylvo-pastoral species, and is traditionally utilized in Morocco for treating a variety of ailments. This current investigation aims to ascertain the antioxidant, antimicrobial, and cytotoxic properties of the ethanolic extract of C. siliqua leaves (CSEE). Initially, we analyzed the chemical composition of CSEE through high-performance liquid chromatography with Diode-Array Detection (HPLC-DAD). Subsequently, we conducted various assessments, including DPPH scavenging capacity, β-carotene bleaching assay, ABTS scavenging, and total antioxidant capacity assays to evaluate the antioxidant activity of the extract. In this study, we investigated the antimicrobial properties of CSEE against five bacterial strains (two gram-positive, Staphylococcus aureus, and Enterococcus faecalis; and three gram-negative bacteria, Escherichia coli, Escherichia vekanda, and Pseudomonas aeruginosa) and two fungi (Candida albicans, and Geotrichum candidum). Additionally, we evaluated the cytotoxicity of CSEE on three human breast cancer cell lines (MCF-7, MDA-MB-231, and MDA-MB-436) and assessed the potential genotoxicity of the extract using the comet assay. Through HPLC-DAD analysis, we determined that phenolic acids and flavonoids were the primary constituents of the CSEE extract. The results of the DPPH test indicated a potent scavenging capacity of the extract with an IC₅₀ of 302.78 ± 7.55 µg/mL, which was comparable to that of ascorbic acid with an IC₅₀ of 260.24 ± 6.45 µg/mL. Similarly, the β-carotene test demonstrated an IC₅₀ of 352.06 ± 12.16 µg/mL, signifying the extract's potential to inhibit oxidative damage. The ABTS assay revealed IC₅₀ values of 48.13 ± 3.66 TE µmol/mL, indicating a strong ability of CSEE to scavenge ABTS radicals, and the TAC assay demonstrated an IC₅₀ value of 165 ± 7.66 µg AAE/mg. The results suggest that the CSEE extract had potent antioxidant activity. Regarding its antimicrobial activity, the CSEE extract was effective against all five tested bacterial strains, indicating its broad-spectrum antibacterial properties. However, it only showed moderate activity against the two tested fungal strains, suggesting it may not be as effective against fungi. The CSEE exhibited a noteworthy dose-dependent inhibitory activity against all the tested tumor cell lines in vitro. The extract did not induce DNA damage at the concentrations of 6.25, 12.5, 25, and 50 µg/mL, as assessed by the comet assay. However, the 100 µg/mL concentration of CSEE resulted in a significant genotoxic effect compared to the negative control. A computational analysis was conducted to determine the physicochemical and pharmacokinetic characteristics of the constituent molecules present in the extract. The Prediction of Activity Spectra of Substances (PASS) test was employed to forecast the potential biological activities of these molecules. Additionally, the toxicity of the molecules was evaluated using the Protox II webserver.

Identification of Breast Cancer Subtypes by Integrating Genomic Analysis with the Immune Microenvironment

Objectives: We aim to identify the breast cancer (BC) subtype clusters and the crucial gene classifier prognostic signatures by integrating genomic analysis with the tumor immune microenvironment (TME). Methods: Data sets of BC were derived from the Cancer Genome Atlas (TCGA), METABRIC, and Gene Expression Omnibus (GEO) databases. Unsupervised consensus clustering was carried out to obtain the subtype clusters of BC patients. Weighted gene coexpression network analysis (WGCNA), least absolute shrinkage and selection operator (LASSO), and univariate and multivariate regression analysis were employed to obtain the gene classifier signatures and their biological functions, which were validated by the BC dataset from the METABRIC database. Additionally, to evaluate the overall survival rates of BC patients, Kaplan-Meier survival analysis was carried out. Moreover, to assess how BC subtype clusters are related to the TME, single-cell analysis was performed. Finally, the drug sensitivity and the immune cell infiltration for different phenotypes of BC patients were also calculated by the CIBERSORT and ESTIMATE algorithms. Results : TCGA-BC samples were divided into three subtype clusters, S1, S2, and S3, among which the prognosis of S2 was poor and that of S1 and S3 were better. Three key pathways and 10 crucial prognostic-related gene signatures are screened. Finally, single-cell analysis suggests that S1 samples have the most types of immune cells, S2 with more sensitivity to tumor treatment drugs are enriched with more neutrophils, and more multilymphoid progenitor cells are involved in subtype cluster S3. Conclusions: Our novelty was to identify the BC subtype clusters and the gene classifier signatures employing a large-amount dataset combined with multiple bioinformatics methods. All of the results provide a basis for clinical precision treatment of BC.

Naringenin and Hesperidin as Promising Alternatives for Prevention and Co-Adjuvant Therapy for Breast Cancer

Citrus (genus Citrus L.) fruits are essential sources of bioactive compounds with antioxidant properties, such as flavonoids. These polyphenolic compounds are divided into subclasses, in which flavanones are the most prominent. Among them, naringenin and hesperidin are emerging compounds with anticancer potential, especially for breast cancer (BC). Several mechanisms have been proposed, including the modulation of epigenetics, estrogen signaling, induction of cell death via regulation of apoptotic signaling pathways, and inhibition of tumor invasion and metastasis. However, this information is sparse in the literature and needs to be brought together to provide an overview of how naringenin and hesperidin can serve as therapeutic tools for drug development and as a successful co-adjuvant strategy against BC. This review detailed such mechanisms in this context and highlighted how naringenin and hesperidin could interfere in BC carcinogenesis and be helpful as potential alternative therapeutic sources for breast cancer treatment.

Honey: A Promising Therapeutic Supplement for the Prevention and Management of Osteoporosis and Breast Cancer

Osteoporosis and breast cancer are serious diseases that have become a significant socioeconomic burden. There are biochemical associations between the two disorders in terms of the amended function of estrogen, receptor activator of nuclear factor kappa beta ligand, oxidative stress, inflammation, and lipid accumulation. Honey as a functional food with high antioxidant and anti-inflammatory properties can contribute to the prevention of various diseases. Its health benefits are mainly related to the content of polyphenols. This review aims to summarize the current knowledge from in vitro, animal, and human studies on the use of honey as a potential therapeutic agent for osteoporosis and breast cancer. Preclinical studies have revealed a beneficial impact of honey on both bone health (microstructure, strength, oxidative stress) and breast tissue health (breast cancer cell proliferation and apoptosis, tumor growth rate, and volume). The limited number of clinical trials, especially in osteoporosis, indicates the need for further research to evaluate the potential benefits of honey in the treatment. Clinical studies related to breast cancer have revealed that honey is effective in increasing blood cell counts, interleukin-3 levels, and quality of life. In summary, honey may serve as a prospective therapeutic supplement for bone and breast tissue health.

Triclosan is associated with breast cancer via oxidative stress and relative telomere length

Introduction

Triclosan (TCS), a widely prescribed broad-spectrum antibacterial agent, is an endocrine-disrupting chemical. The relationship and biological mechanisms between TCS exposure and breast cancer (BC) are disputed. We aimed to examine the correlation between urinary TCS exposure and BC risk and estimated the mediating effects of oxidative stress and relative telomere length (RTL) in the above association.

Methods

This case-control study included 302 BC patients and 302 healthy individuals in Wuhan, China. We detected urinary TCS, three common oxidative stress biomarkers [8-hydroxy-2-deoxyguanosine (8-OHdG), 8-iso-prostaglandin F_2α (8-isoPGF_2α), 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA)], and RTL in peripheral blood mononuclear cells.

Results

Significant associations were observed between log-transformed urinary concentrations of TCS, 8-OHdG, HNE-MA, 8-isoPGF_2α, RTL, and BC risk, with the odds ratios (95% confidence intervals) being 1.58 (1.32-1.91), 3.08 (1.55-6.23), 3.39 (2.45-4.77), 3.99 (2.48-6.54), and 1.67 (1.35-2.09), respectively. Continuous TCS exposure was significantly positively correlated with RTL, HNE-MA, and 8-isoPGF_2α (all p<0.05) but not with 8-OHdG (p = 0.060) after adjusting for covariates. The mediated proportions of 8-isoPGF2_2α and RTL in the relationship between TCS and BC risk were 12.84% and 8.95%, respectively (all p<0.001).

Discussion

In conclusion, our study provides epidemiological evidence to confirmed the deleterious effects of TCS on BC and indicated the mediating effect of oxidative stress and RTL on the correlation between TCS and BC risk. Moreover, exploring the contribution of TCS to BC can clarify the biological mechanisms of TCS exposure, provide new clues for the pathogenesis of BC, which is of great significance to improving public health systems.

Antitumor effect of selenium-rich Brazil nuts and selenomethionine dietary supplementation on pre-existing 4T1 mammary tumor growth in mice

Selenium (Se) is an essential micronutrient known to play an important role in the antioxidant system that can potentially influence tumor growth. We aimed to investigate the effects of dietary Se supplementation after detection of 4T1 mammary tumor growth in BALB/c mice. Thirty female mice received subcutaneous inoculation of 4T1 cells. After five days, all animals presenting palpable tumors were randomly assigned to three groups: a control group (Se-control) receiving a diet with adequate Se (0.15 mg/kg) and two other groups that received Se-supplemented diets (1.4 mg/kg of total Se) with either Brazilian nuts (Se-Nuts) or selenomethionine (SeMet). Data were assessed by either One or Two-way ANOVA followed by Tukey's HSD or Bonferroni's post hoc tests, respectively. Both Se-supplemented diets reduced tumor volume from the thirteenth day of feeding compared with the Se-adequate (control) diet (p < 0.05). The SeMet group presented a higher Se blood concentration (p < 0.05) than the Se-control group, with the Se-Nuts group presenting intermediate values. Selenoprotein P gene expression in the liver was higher in the Se-Nuts group than in the Se-control group (p < 0.05), while the SeMet group presented intermediate expression. Dietary Se supplementation, starting after detection of 4T1 palpable lesions, reduced tumor volume in mice.

Low to moderate adherence to 2018 diet and physical exercise recommendations of the World Cancer Research Fund/American Institute for Cancer Research is associated with prooxidant biochemical profile in women undergoing adjuvant breast cancer treatment

Adequate adherence to the 2018 diet and exercise recommendations of the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) can possibly result in less oxidative stress, lower risk to chemo- and radiotoxicity, lower risk of relapse, and increased quality of life in breast cancer survivors. This observational study aims to investigate the influence of adherence to updated recommendations of the WCRF/AICR on oxidative stress biomarkers in women with breast cancer undergoing adjuvant treatment (AT). We hypothesized that adherence to WCRF/AICR recommendations is inversely related to oxidative damage biomarkers and directly associated with antioxidant status. Women (n = 78) were evaluated before (T0) and after AT. After collecting anthropometric, physical activity, and food consumption data, a standardized score of adherence to WCRF/AICR recommendations was applied. The sample was divided into low-medium adherence and high adherence groups. Blood samples were collected at both timepoints for oxidative stress biomarkers analysis. Multiple linear regression analyzes were applied to verify associations between WCRF/AICR score and biomarkers. We found that low-medium adherence to WCRF/AICR recommendations at T0 affected lower levels of reduced glutathione (P= .003) and higher levels of lipid hydroperoxides (P= .002) and plasma carbonylated proteins (P= .001) after AT. The WCRF/AICR score at T0 was inversely associated with changes in plasma carbonylated protein concentrations after AT (adjusted β = -0.359; P= .01). Our findings suggest that high WCRF/AICR score before and during AT may provide greater stability of antioxidant capacity and protection against exacerbated oxidative stress.

A Lower Serum Antioxidant Capacity as a Distinctive Feature for Women with HER2+ Breast Cancer: A Preliminary Study

The overexpression of HER2 in breast cancer (BC) can contribute to redox imbalance, which is related to damage and structural modification in many biomolecules. To the best of our knowledge, this is the first study that has investigated the infrared spectrum wavenumbers obtained by ATR-FTIR and their relationship with the levels of redox status markers such as reduced glutathione, superoxide dismutase (SOD), catalase, Ferric Reducing Antioxidant Power (FRAP), and protein carbonyl among women with HER2+ BC, HER2- BC, and benign breast disease (BBD). The study was conducted with 25 women, 17 of whom were diagnosed with BC (6 HER2+ and 11 HER2-) and 8 with BBD. Our results indicate HER2+ BC cases could be distinguished from HER2- BC and BBD cases by their serum's antioxidant capacity [HER2+ BC vs. HER2- BC (AUC = 0.818; specificity = 81.82%; sensitivity = 66.67%); HER2+ BC vs. BBD (AUC = 0.875; specificity = 75%; sensitivity = 83.33%)]. The changes in biochemical terms that occur in serum as a result of the scarcity of antioxidants are related to a peculiar fingerprint in the infrared spectrum obtained by ATR-FTIR. In the serum of women with BBD, the SOD enzyme level is the highest, and this characteristic allowed us to distinguish them from HER2- BC. Finally, data regarding the serological antioxidant capacity of FRAP and the infrared spectrum by ATR-FTIR will allow us to assess biochemical changes that occur before clinical signs, indicating whether changes in therapy or interventions are necessary.

circRNAs and their relationship with breast cancer: a review

BACKGROUND

Recently, an increasing number of studies have been conducted on circular RNAs (circRNAs) that have demonstrated their different roles in a variety of biological processes. Moreover, a large number of circRNAs have been shown to be involved in the occurrence and development of breast cancer (BC).

MAIN BODY

Both functional and mechanistic experiments have shown that circular RNAs (circRNAs) can act as competing endogenous RNAs by sponging miRNAs, encoding proteins, and regulating parental genes. In doing so, circRNAs modulate the proliferation, migration, apoptosis, and invasion of BC cells in vitro as well as tumor growth and metastasis in vivo. Moreover, scores of circRNAs have been demonstrated to be related to clinicopathological features, prognosis, and treatment sensitivity in patients with BC; many circRNAs have shown potential as biomarkers for diagnosis, drug sensitivity, and prognosis prediction. Furthermore, researchers have focused on circRNAs as potential therapeutic targets.

CONCLUSION

In this review, we briefly summarize the functions and categories of circRNAs, their different roles in BC, and recent research and therapeutic progress related to circRNAs.

SOD2 Gene Variants (rs4880 and rs5746136) and Their Association with Breast Cancer Risk

The superoxide dismutase (SOD) is the principal antioxidant defense system in the body that is activated by a reactive oxygen species. Some variants of the SOD2 gene have been associated with cancer. The rs4880 variant was determined by PCR real-time and the rs5746136 variant by PCR-RFLP in healthy subjects and in breast cancer (BC) patients. The rs4880 and rs5746136 variants were associated with BC susceptibility when BC patients and the control group were compared for the CT, TT, CTCC, and the T alleles (p < 0.05). The CT genotype of the rs4880 variant showed significant statistical differences in patients and controls aged ≤ 45 years old, and with hormonal consumption (p < 0.05). The rs4880 variant was associated with BC patients with CTTT genotype and obesity, the presence of DM2-SAH, and a non-chemotherapy response (p < 0.05). Additionally, the rs5746136 variant was associated with susceptibility to BC with Ki-67 (≥20%), luminal A type BC, and a chemotherapy partial response (p < 0.05) in BC patients who carry TT, TC, and CTTT genotypes, respectively. The haplotype T/T (OR 1.98; 95% CI 1.20−3.26, p = 0.005) was observed to be a risk factor for BC. The rs4880 and rs5746136 variants in the SOD2 gene were associated with BC susceptibility.

Oxidative stress genes in patients with esophageal squamous cell carcinoma: construction of a novel prognostic signature and characterization of tumor microenvironment infiltration

Background

Oxidative stress plays an important role in the progression of various types of tumors. However, its role in esophageal squamous cell carcinoma (ESCC) has seldom been explored. This study aimed to discover prognostic markers associated with oxidative stress in ESCC to improve the prediction of prognosis and help in the selection of effective immunotherapy for patients.

Results

A consensus cluster was constructed using 14 prognostic differentially expressed oxidative stress-related genes (DEOSGs) that were remarkably related to the prognosis of patients with ESCC. The infiltration levels of neutrophils, plasma cells, and activated mast cells, along with immune score, stromal score, and estimated score, were higher in cluster 1 than in cluster 2. A prognostic signature based on 10 prognostic DEOSGs was devised that could evaluate the prognosis of patients with ESCC. Calculated risk score proved to be an independent clinical prognostic factor in the training, testing, and entire sets. P53 signaling pathway was highly enriched in the high-risk group. The calculated risk score was positively related to the infiltration levels of resting mast cells, memory B cells, and activated natural killer (NK) cells and negatively associated with the infiltration levels of M1 and M2 macrophages. The relationship between clinical characteristics and risk score has not been certified. The half-maximal inhibitory concentration (IC50) values for sorafenib and gefitinib were lower for patients in the low-risk group.

Conclusion

Our prognostic signature based on 10 prognostic DEOSGs could predict the disease outcomes of patients with ESCC and had strong clinical value. Our study improves the understanding of oxidative stress in tumor immune microenvironment (TIME) and provides insights for developing improved and efficient immunotherapy strategies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12859-022-04956-9.

The oxidoreductase CLIC4 is required to maintain mitochondrial function and resistance to exogenous oxidants in breast cancer cells

The chloride intracellular channel-4 (CLIC4) is one of the six highly conserved proteins in the CLIC family that share high structural homology with GST-omega in the GST superfamily. While CLIC4 is a multifunctional protein that resides in multiple cellular compartments, the discovery of its enzymatic glutaredoxin-like activity in vitro suggested that it could function as an antioxidant. Here, we found that deleting CLIC4 from murine 6DT1 breast tumor cells using CRISPR enhanced the accumulation of reactive oxygen species (ROS) and sensitized cells to apoptosis in response to H2O2 as a ROS-inducing agent. In intact cells, H2O2 increased the expression of both CLIC4 mRNA and protein. In addition, increased superoxide production in 6DT1 cells lacking CLIC4 was associated with mitochondrial hyperactivity including increased mitochondrial membrane potential and mitochondrial organelle enlargement. In the absence of CLIC4, however, H2O2-induced apoptosis was associated with low expression and degradation of the antiapoptotic mitochondrial protein Bcl2 and the negative regulator of mitochondrial ROS, UCP2. Furthermore, transcriptomic profiling of H2O2-treated control and CLIC4-null cells revealed upregulation of genes associated with ROS-induced apoptosis and downregulation of genes that sustain mitochondrial functions. Accordingly, tumors that formed from transplantation of CLIC4-deficient 6DT1 cells were highly necrotic. These results highlight a critical role for CLIC4 in maintaining redox-homeostasis and mitochondrial functions in 6DT1 cells. Our findings also raise the possibility of targeting CLIC4 to increase cancer cell sensitivity to chemotherapeutic drugs that are based on elevating ROS in cancer cells.

Development of an adverse outcome pathway network for breast cancer: a comprehensive representation of the pathogenesis, complexity and diversity of the disease

Adverse outcome pathways (AOPs), introduced in modern toxicology, intend to provide an evidence-based representation of toxicological effects and facilitate safety assessment of chemicals not solely based on laboratory animal in vivo experiments. However, some toxicological processes are too complicated to represent in one AOP. Therefore, AOP networks are developed that help understanding and predicting toxicological processes where complex exposure scenarios interact and lead to the emergence of the adverse outcome. In this study, we present an AOP network for breast cancer, developed after an in-depth survey of relevant scientific literature. Several molecular initiating events (MIE) were identified and various key events that link the MIEs with breast cancer were described. The AOP was developed according to Organization of Economic Co-Operation and Development (OECD) guidance, weight of evidence was assessed through the Bradford Hill criteria and confidence was tested by the OECD key questions. The AOP network provides a straightforward understanding of the disease onset and progression at different biological levels. It can be used to pinpoint knowledge gaps, identify novel therapeutic targets and act as a stepping stone for the development of novel in vitro test methods for hazard identification and risk assessment of newly developed chemicals and drugs.

Cancer-Associated Exosomal CBFB Facilitates the Aggressive Phenotype, Evasion of Oxidative Stress, and Preferential Predisposition to Bone Prometastatic Factor of Breast Cancer Progression

Background. Despite therapeutic advancements, metastasis remains a major cause in breast cancer-specific mortality. Breast cancer cells are susceptible to oxidative damage and exhibit high levels of oxidative stress, including protein damage, DNA damage, and lipid peroxidation. Some breast cancer risk factors may change the level of endogenous oxidative stress. Circulating exosomes play critical roles in tumorigenesis, distant metastasis, and poor prognosis in patients with breast cancer. Methods. We used an online database to analyze the expression and prognostic value of core binding factor subunit β (CBFB) and oxidative stress–related targets in patients with breast cancer. Serum from healthy controls and patients with primary breast cancer or bone metastatic breast cancer in the bone was collected. Exosomes were isolated from the sera or cell culture media. We used an MDA-MB-436-innoculated tumor xenograft mouse model for silencing CBFB. Results. Circulating exosomes from patients with breast cancer metastasis to the bone were rich in CBFB. The human mammary fibroblast cells HMF3A and fibroblasts derived from patient samples cocultured with exosomes had increased α-SMA and vimentin expression and IL-6 and OPN secretion. Similarly, nonmetastatic breast cancer cells cocultured with exosomes exhibited increased levels of certain markers, including vimentin, snail1, CXCR4, and Runx2, and the exosomes had high CBFB expression. Silencing CBFB in metastatic MDA-MB-436 and MDA-MB-157 cells resulted in suppressed migration and invasion and downregulation of vimentin, CXCR4, snail1, Runx2, CD44, and OPN. Conversely, CBFB overexpression resulted in upregulation of Runx2, vimentin, snail1, CD44, and OPN in nonmetastatic T47D and MCF12A cells. The CBFB-rich exosomes derived from MDA-MB-436 cells induced enhanced metastatic phenotypes in the low-metastatic T47D and MCF12A cell lines. Conclusion. Our results revealed that CBFB may promote bone metastasis in patients with breast cancer. Of therapeutic relevance, targeting CBFB resulted in decreased tumor burden and bone metastasis, downregulation of bone metastasis markers, and impaired regulation of oxidative stress–related proteins NAE1 and NOS1.

Molecular mechanisms of ferroptosis and its role in prostate cancer therapy

Prostate cancer (PCa) is a highly prevalent disease that affects men's health worldwide and is the second most common malignancy in males. Ferroptosis is a novel form of programmed cell death characterized by iron overload and the accumulation of lipid peroxidation, which differs from the regulated cell death modes of necrosis, apoptosis, and autophagy. Substantial progress has been achieved in researching the occurrence and regulatory mechanisms of ferroptosis, which is closely associated with cancer initiation, progression, and suppression and is expected to become a new breakthrough point in the PCa treatment. This review will summarize the mechanisms involved in PCa, and we detail the molecular mechanisms of ferroptosis and its role in PCa treatment.

An Oxidative Stress-Related Genes Signature for Predicting Survival in Bladder Cancer: Based on TCGA Database and Bioinformatics

Background

Oxidative stress (OS) responses have been linked to oncogenesis and tumor progression and have recently been regarded as a potential strategy for tumor therapy. However, OS-related therapeutic targets have not been identified to date in the bladder cancer (BC).

Methods

The mRNA expression and clinical data of BC were downloaded from the public database. Prognostic risk score signature was constructed using LASSO Cox regression analysis. External validation was performed in GSE15307 cohort. ESTIMATE, CIBERSORT, and ssGSEA algorithm were used to analyze immune cell infiltration and immune microenvironment. Next, functional enrichment analysis was performed to elucidate the mechanism underlying the signature. Additionally, we performed a nomogram to forecast the survival rate of individual BC patients.

Results

An OS-related genes (OSRGs) signature was constructed. Overall survival was lower in the high-risk group than in the low-risk group, according to survival analyses. The area under the curve (AUC) of ROC curves further validated the prognostic signature’s strong prediction performance in these two cohorts. The risk score was verified as an independent risk factor for BC by independent prognostic analysis. Moreover, as compared to TNM stage alone, a nomogram that integrated the risk score with TNM stage showed a much superior predictive value. Immune infiltration and tumor microenvironment studies indicated that immune cells and functions may play a significant role in carcinogenesis and development. The levels of expression of prognostic genes were shown to be substantially linked with drug sensitivity.

Conclusion

We developed a novel OSRGs signature for predicting overall survival and impacting the immune status in patients with BC. New nomogram can help clinicians predict the survival rate of BC patients. These findings shed new light on the potential usage of OSRGs signature in BC patients.

Characterization of Mitochondrial Proteome and Function in Luminal A and Basal-like Breast Cancer Subtypes Reveals Alteration in Mitochondrial Dynamics and Bioenergetics Relevant to Their Diagnosis

Breast cancer (BC) is the most prevalent cancer and the one with the highest mortality among women worldwide. Although the molecular classification of BC has been a helpful tool for diagnosing and predicting the treatment of BC, developments are still being made to improve the diagnosis and find new therapeutic targets. Mitochondrial dysfunction is a crucial feature of cancer, which can be associated with cancer aggressiveness. Although the importance of mitochondrial dynamics in cancer is well recognized, its involvement in the mitochondrial function and bioenergetics context in BC molecular subtypes has been scantly explored. In this study, we combined mitochondrial function and bioenergetics experiments in MCF7 and MDA-MB-231 cell lines with statistical and bioinformatics analyses of the mitochondrial proteome of luminal A and basal-like tumors. We demonstrate that basal-like tumors exhibit a vicious cycle between mitochondrial fusion and fission; impaired but not completely inactive mitochondrial function; and the Warburg effect, associated with decreased oxidative phosphorylation (OXPHOS) complexes I and III. Together with the results obtained in the cell lines and the mitochondrial proteome analysis, two mitochondrial signatures were proposed: one signature reflecting alterations in mitochondrial functions and a second signature exclusively of OXPHOS, which allow us to distinguish between luminal A and basal-like tumors.

Emerging Roles of COX7RP and Mitochondrial Oxidative Phosphorylation in Breast Cancer

Metabolic alterations are critical events in cancers, which often contribute to tumor pathophysiology. While aerobic glycolysis is a known characteristic of cancer-related metabolism, recent studies have shed light on mitochondria-related metabolic pathways in cancer biology, including oxidative phosphorylation (OXPHOS), amino acid and lipid metabolism, nucleic acid metabolism, and redox regulation. Breast cancer is the most common cancer in women; thus, elucidation of breast cancer-related metabolic alteration will help to develop cancer drugs for many patients. We here aim to define the contribution of mitochondrial metabolism to breast cancer biology. The relevance of OXPHOS in breast cancer has been recently defined by the discovery of COX7RP, which promotes mitochondrial respiratory supercomplex assembly and glutamine metabolism: the latter is also shown to promote nucleic acid and fatty acid biosynthesis as well as ROS defense regulation. In this context, the estrogen-related receptor (ERR) family nuclear receptors and collaborating coactivators peroxisome proliferator-activated receptor-γ coactivator-1 (PGC-1) are essential transcriptional regulators for both energy production and cancer-related metabolism. Summarizing recent findings of mitochondrial metabolism in breast cancer, this review will aim to provide a clue for the development of alternative clinical management by modulating the activities of responsible molecules involved in disease-specific metabolic alterations.

Metabolic Features of Saliva in Breast Cancer Patients

The aim of the work was to study the metabolic characteristics of saliva in breast cancer and the subsequent assessment of the potential information content of its individual biochemical indicators. The study included 487 patients of the Omsk Clinical Oncology Center with morphologically verified breast cancer and 298 volunteers without breast pathologies. Saliva samples were obtained from all patients before the start of treatment, and the values of 34 biochemical indicators were determined. It has been shown that concentration of total protein, urea, uric acid (UA), the total content of α-amino acids and lipid peroxidation products, and the activity of metabolic and antioxidant enzymes (in particular catalase—CAT) of saliva changed significantly in breast cancer. Biochemical indicators characterizing early breast cancer have been identified, which can be used for timely diagnosis in addition to existing methods. The coefficients UA/Urea and UA·CAT/Urea are proposed, for which the maximum deviation from the norm was observed in the early stages of the disease. It was shown that for ductal breast cancer, changes in the activity of metabolic enzymes of saliva were more pronounced, while, for lobular breast cancer, the indicators of enzymatic and non-enzymatic components of antioxidant protection changed. The results confirmed the potential importance of saliva in the diagnosis of breast cancer.

Impacts of oxidants and antioxidants on the emergence and progression of Alzheimer's disease

The brain shows a high sensitivity to oxidative stress (OS). Thus, the maintenance of homeostasis of the brain regarding the reduction-oxidation (redox) situation is crucial for the regular function of the central nervous systems (CNS). The imbalance between the reactive oxygen species (ROS) and the cellular mechanism might lead to the emergence of OS, causing profound cell death as well as tissue damages and initiating neurodegenerative disorders (NDDs). Characterized by the cytoplasmic growth of neurofibrillary tangles and extracellular β-amyloid plaques, Alzheimer's disease (AD) is a complex NDD that causes dementia in adult life with severe manifestations. Nuclear factor erythroid 2-related factor 2 (NRF2) is a key transcription factor that regulates the functional expression of OS-related genes and the functionality of endogenous antioxidants. In the case of oxidative damage, NRF2 is transferred to the nucleus and attached to the antioxidant response element (ARE) that enhances the sequence to initiate transcription of the cell-protecting genes. This review articulates various mechanisms engaged with the generation of active and reactive species of endogenous and exogenous oxidants and focuses on the antioxidants as a body defense system regarding the NRF2-ARE signaling path in the CNS.

Hypomagnesemia and Its Relationship with Oxidative Stress Markers in Women with Breast Cancer

Reduced serum magnesium concentrations in women with breast cancer compromises one of the antioxidant defense system involved in the carcinogenesis process. To evaluate parameters of magnesium, the enzyme activity of superoxide dismutase, and its relation with oxidative stress markers in women with breast cancer. A case-control study was conducted, involving 60 women in the age range between 29 and 65 years, divided into two groups: women with breast cancer (n = 30) and women without breast cancer (n = 30). Plasma; ionized, erythrocytic, and urinary magnesium intake; plasma concentrations of thiobarbituric acid reactive substances; and erythrocyte superoxide dismutase enzyme activity were evaluated. The mean value of the amount of dietary magnesium was below the recommended level in both groups studied, with no statistical difference (p > 0.05). Plasma, ionized, and erythrocyte magnesium concentrations of women with breast cancer were reduced in relation to the control group (p < 0.0001) and inadequate according to the reference values. Urinary excretion was high, with a significant difference between groups (p < 0.0001). The mean concentration of thiobarbituric acid reactive substances was high in the study participants, with no significant statistical difference between the groups (p > 0.05). The mean values of superoxide dismutase enzyme activity were adequate, with no statistically significant difference between the groups (p > 0.05). Women with breast cancer have impaired magnesium homeostasis, characterized by its reduction in diet, plasma, and erythrocytes and its increase in urine.

Dietary Antioxidant Capacity Promotes a Protective Effect against Exacerbated Oxidative Stress in Women Undergoing Adjuvant Treatment for Breast Cancer in a Prospective Study

Breast cancer (Bca) is the most common type of cancer among women worldwide, and oxidative stress caused by adjuvant treatment may be decreased by antioxidant intake. The aim of this study is to investigate the associations between Dietary antioxidant Capacity (DaC) and oxidation and antioxidant biomarkers in women undergoing adjuvant treatment (AT) for Bca. This prospective study had a sample of 70 women (52.2 ± 10.7 y). DaC (mmol/g) was calculated using nutritional data obtained from a Food Frequency Questionnaire, and blood was collected to measure the oxidation and antioxidant biomarkers at baseline (T0), and after AT (T1). Carbonylated protein levels were inversely associated with DaC at T1 (p = 0.004); women showed an increased risk of having increment on lipid hydroperoxides and thiobarbituric acid reactive substances (TBARS), and decrement on ferric reducing antioxidant power (FRAP) and reduced glutathione after AT, in response to lowered DaC (p < 0.05). Carbonylated proteins, TBARS and FRAP levels remained stable between the periods for women at the 3rd DaC tertile at T1, differentiating them from those at the 1st tertile, who showed negative changes in these biomarkers (p < 0.04). DaC may be beneficial for women undergoing AT for Bca, since it promoted a reduction in oxidative stress.

Halophilic Carotenoids and Breast Cancer: From Salt Marshes to Biomedicine

Breast cancer is the leading cause of death among women worldwide. Over the years, oxidative stress has been linked to the onset and progression of cancer. In addition to the classical histological classification, breast carcinomas are classified into phenotypes according to hormone receptors (estrogen receptor-RE-/progesterone receptor-PR) and growth factor receptor (human epidermal growth factor receptor-HER2) expression. Luminal tumors (ER/PR-positive/HER2-negative) are present in older patients with a better outcome. However, patients with HER2-positive or triple-negative breast cancer (TNBC) (ER/PR/HER2-negative) subtypes still represent highly aggressive behavior, metastasis, poor prognosis, and drug resistance. Therefore, new alternative therapies have become an urgent clinical need. In recent years, anticancer agents based on natural products have been receiving huge interest. In particular, carotenoids are natural compounds present in fruits and vegetables, but algae, bacteria, and archaea also produce them. The antioxidant properties of carotenoids have been studied during the last years due to their potential in preventing and treating multiple diseases, including cancer. Although the effect of carotenoids on breast cancer during in vitro and in vivo studies is promising, clinical trials are still inconclusive. The haloarchaeal carotenoid bacterioruberin holds great promise to the future of biomedicine due to its particular structure, and antioxidant activity. However, much work remains to be performed to draw firm conclusions. This review summarizes the current knowledge on pre-clinical and clinical analysis on the use of carotenoids as chemopreventive and chemotherapeutic agents in breast cancer, highlighting the most recent results regarding the use of bacterioruberin from haloarchaea.

Simultaneous inhibition of breast cancer and its liver and lung metastasis by blocking inflammatory feed-forward loops

Inflammatory feed-forward loops including the steps of "inflammatory cell recruitment", "inflammatory signaling pathway activation" and "inflammatory factor production" are essential in the development of breast cancer and its metastasis. Herein, a doxorubicin-loaded micellar low-molecular-weight-heparin-astaxanthin nanoparticle (LMWH-AST/DOX, LA/DOX NP) was developed. The hydrophilic LMWH could decrease the recruitment of neutrophils in liver and myeloid-derived suppressor cells (MDSCs) in lung and tumor through P-selectin blockage. The hydrophobic AST could inhibit nuclear factor-κB (NF-κB) and signal transducer and activator of transcription 3 (STAT3) signaling pathways. Therefore, LA/DOX NPs could block these loops and suppress the liver metastasis by inhibiting the formation of neutrophil extracellular traps (NETs), inhibit the lung metastasis and alleviate the inflammatory and immunosuppressive microenvironment in tumor. This is the first functional nanoparticle reported to shut down inflammatory feed-forward loops and the formation of NETs, which provides a promising therapeutic strategy for breast cancer and its liver and lung metastasis.

Serum concentrations of organochlorine pesticides, biomarkers of oxidative stress, and risk of breast cancer

Studies have documented that exposure to organochlorine pesticides (OCPs) is linked with breast cancer, but the underlying biological mechanisms are still unknown. This study included 313 women diagnosed with breast cancer and 313 controls in Wuhan, China, and measured 18 OCPs in serum and 3 oxidative stress biomarkers in urine. Multivariable adjusted regression models were used to evaluate the associations among OCPs, oxidative stress biomarkers, and breast cancer. The mediating effect of oxidative stress was assessed by mediation analysis. We observed that most OCPs were positively associated with risk of breast cancer (all FDR-P values < 0.05 or 0.10). Moreover, we found that p,p'-DDT, p,p'-DDD, dieldrin, heptachlor, and heptachlor epoxide were positively associated with 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA) and 8-iso-prostaglandin F_2α (8-isoPGF_2α), which in turn were positively associated with risk of breast cancer. Mediation analysis indicated that HNE-MA and 8-isoPGF_2ɑ mediated the positive associations between these OCPs and risk of breast cancer, with mediating proportion ranging from 6.23% to 19.9%. Our results suggest that lipid peroxidation may mediate the positive associations between OCP exposures and risk of breast cancer.

The Interleukin-6/Signal Transducer and Activator of Transcription-3/Cystathionine γ-Lyase Axis Deciphers the Transformation Between the Sensitive and Resistant Phenotypes of Breast Cancer Cells

Drug resistance of cancer cells is associated with redox homeostasis. The mechanism of acquired resistance of cancer cells to antitumor drugs is not well understood. Our previous studies revealed that drug resistance and highly expressed P-glycoprotein (P-gp) of MCF-7 breast cancer cells was dependent on intracellular redox homeostasis and declined capacity for scavenging reactive oxygen species (ROS). Recently, we observed that, unlike nontumorigenic cells MCF-10A, three tumorigenic breast cancer cells (MCF-7S, BT474, MDA-MB-231) reprogrammed their metabolism, highly expressed cystathionine-γ-lyase (CTH), and acquired a particular specialty to use methionine (Met) to synthesize glutathione (GSH) through the transsulfuration pathway. Interestingly, doxorubicin (adriamycin) further reprogrammed metabolism of MCF-7 cells sensitive to adriamycin (MCF-7S) and induced them to be another MCF-7 cell line resistant to adriamycin (MCF-7R) with dramatically downregulated CTH. The two MCF-7 cell lines showed distinctly different phenotypes in terms of intracellular GSH, ROS levels, expression and activity of P-gp and CTH, and drug resistance. We showed that CTH modulation or the methionine supply brought about the interconversion between MCF-7S and MCF-7R. Methionine deprivation or CTH silencing induced a resistant MCF-7R and lowered paclitaxel activity, yet methionine supplementation or CTH overexpression reversed the above effects, induced a sensitive phenotype of MCF-7S, and significantly increased the cytotoxicity of paclitaxel both in vitro and in vivo. Interleukin-6 (IL-6)/signal transducer and activator of transcription-3 (STAT3) initiated CTH expression and activity, and the effect on the resistant phenotype was exclusively dependent on CTH and ROS. This study suggests that the IL-6/STAT3/CTH axis plays a key role in the transformation between sensitive and resistant MCF-7 cells. SIGNIFICANCE STATEMENT: Cystathionine γ-lyase (CTH) plays a key role in transformation between the sensitive and resistant phenotypes of MCF-7 cells and is dependent on the interleukin-6 (IL-6)/signal transducer and activator of transcription-3 (STAT3) signaling axis. Modulation of the transsulfuration pathway on CTH or IL-6/STAT3 or methionine supplementation is beneficial for reversing the resistance of MCF-7 cells, which indicates a clinical translation potential.

Impacting the Remedial Potential of Nano Delivery-Based Flavonoids for Breast Cancer Treatment

Breast cancer persists as a diffuse source of cancer despite persistent detection and treatment. Flavonoids, a type of polyphenol, appear to be a productive option in the treatment of breast cancer, because of their capacity to regulate the tumor related functions of class of compounds. Plant polyphenols are flavonoids that appear to exhibit properties which are beneficial for breast cancer therapy. Numerous epidemiologic studies have been performed on the dynamic effect of plant polyphenols in the prevention of breast cancer. There are also subclasses of flavonoids that have antioxidant and anticarcinogenic activity. These can regulate the scavenging activity of reactive oxygen species (ROS) which help in cell cycle arrest and suppress the uncontrolled division of cancer cells. Numerous studies have also been performed at the population level, one of which reported a connection between cancer risk and intake of dietary flavonoids. Breast cancer appears to show intertumoral heterogeneity with estrogen receptor positive and negative cells. This review describes breast cancer, its various factors, and the function of flavonoids in the prevention and treatment of breast cancer, namely, how flavonoids and their subtypes are used in treatment. This review proposes that cancer risk can be reduced, and that cancer can be even cured by improving dietary intake. A large number of studies also suggested that the intake of fruit and vegetables is associated with reduced breast cancer and paper also includes the role and the use of nanodelivery of flavonoids in the healing of breast cancer. In addition, the therapeutic potential of orally administered phyto-bioactive compounds (PBCs) is narrowed because of poor stability and oral bioavailability of compounds in the gastrointestinal tract (GIT), and solubility also affects bioavailability. In recent years, creative nanotechnology-based approaches have been advised to enhance the activity of PBCs. Nanotechnology also offers the potential to become aware of disease at earlier stages, such as the detection of hidden or unconcealed metastasis colonies in patients diagnosed with lung, colon, prostate, ovarian, and breast cancer. However, nanoformulation-related effects and safety must not be overlooked. This review gives a brief discussion of nanoformulations and the effect of nanotechnology on herbal drugs.

Improvement in Redox Homeostasis after Cytoreductive Surgery in Colorectal Adenocarcinoma

Colorectal cancer (CRC) as one the most common cancer type is associated with oxidative stress. Surgery is the only curative modality for early-stage CRC. The aim of this study was to evaluate the oxidative damage biomarkers as well as enzymatic and nonenzymatic antioxidants in patients with CRC before and after tumor resection and in healthy controls. 60 patients with stage I/II colorectal adenocarcinoma and 43 healthy controls were recruited in this study. We measured plasma levels of oxidative damage biomarkers, including advanced oxidation protein products (AOPP), advanced glycation end products (AGEs), malondialdehyde (MDA), and oxidized low-density lipoprotein (ox-LDL) at baseline and after tumor removal. We also evaluated the plasma activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) as enzymatic antioxidants and the ferric reducing antioxidant power (FRAP) assay for nonenzymatic antioxidant capacity. Patients with CRC had significantly higher AGE, AOPP, MDA, and ox-LDL and also FRAP levels and higher SOD and GPx and lower CAT activity levels compared to healthy controls (p < 0.05). We did not observe any statistically significant correlation between redox biomarkers and the size and stage of the tumor. AGEs (72.49 ± 4.7 vs. 67.93 ± 8.8, p < 0.001), AOPP (137.64 ± 21.9 vs. 119.08 ± 33.1, p < 0.001), MDA (3.56 ± 0.30 vs. 3.05 ± 0.33, p < 0.001), and ox-LDL (19.78 ± 0.97 vs. 16.94 ± 1.02, p < 0.001) concentrations reduced significantly after tumor removal. The largest effect sizes were found in ox-LDL (d = -2.853, 95% CI 2.50-3.19) and MDA (d = -1.617, 95% CI 0.43-0.57). Serum FRAP levels (1097.5 ± 156.7 vs. 1239.3 ± 290, p < 0.001) and CAT (2.34 ± 0.34 vs. 2.63 ± 0.38, p < 0.001), GPx (102.37 ± 6.58 vs. 108.03 ± 6.95, p < 0.001), and SOD (5.13 ± 0.39 vs. 5.53 ± 0.31, p < 0.001) activity levels increased significantly after surgery. The largest effect sizes among antioxidants were seen in SOD (d = 1.135, 95% CI 0.46-0.34) and GPx (d = 0.836, 95% CI 0.35-0.23). This study indicated that patients with colorectal cancer had higher levels of oxidative stress and antioxidant activity compared to healthy controls. After surgical resection of tumor, we observed a substantial improvement in redox homeostasis.

Parasporin A13-2 of Bacillus thuringiensis Isolates from the Papaloapan Region (Mexico) Induce a Cytotoxic Effect by Late Apoptosis against Breast Cancer Cells

The protein A13-2 was obtained from Bacillus thuringiensis strains isolated from the Papaloapan watershed region (Oaxaca, Mexico). The cytotoxic activity of parasporal inclusions was studied against breast cancer cell line (MCF-7) and normal cell (human peripheral blood mononuclear cells). The MTT, the formation of reactive species, nitric oxide, free cell DNA, and the type of death cellular were assessed. The protein A13-2 shows the highest cytotoxic activity against MCF-7 (13% cell viability at 6 µg/mL), the extracellular DNA increases, and it shows no stress for reactive species or nitric oxide. Besides, the A13-2 parasporin shows no toxicity to peripheral blood mononuclear cells, and it does not generate changes in nitric oxide levels or free cell DNA. Due to that, the cytotoxic effect of A13-2 was specific for MCF-7, and it does not affect normal cells. According to microscopy and flow cytometry, A13-2 parasporin leads to the death of MCF-7 cells by late apoptosis together with necrosis and without allowing the triggering of the survival mechanisms. When analyzed together, our results show for the first time that the A13-2 protein isolated from Mexican strains of B. thuringiensis preferentially kills MCF- 7 (cancer cells) over HEK 293 and PBMC cell lines (normal cells), thus representing a promising alternative for the treatment of cancer breast.