Evaluation of Potential Mechanisms Controlling the Catalase Expression in Breast Cancer Cells

Unveiling the therapeutic potential of plant steroid peimine: A study on apoptotic induction in MRMT-1 cell line-induced breast cancer in rats

BACKGROUND

Breast cancer stands as a leading contributor to global cancer-related mortality. Progressing Research and Medical Innovations Elevate Treatment Choices and Results for Breast Cancer. Among these, Peimine, a natural steroid inherent in plants, notably within the Fritillaria species, demonstrates the capability to trigger apoptosis in breast cancer cells through the mitochondrial membrane permeation pathway. Nevertheless, its impact on an appropriate cancer model remains an area necessitating further exploration.

AIM

This study explored the in vivo anticancer effects of peimine on MRMT-1 Cell-line induced breast cancer in rats.

METHOD

Cancer was induced by the administration of MRMT-1 (6 x 106 cells) cells in the mammary pads of SD rats. The daily drug treatmentcommenced on day 14 and continued till 39 days. Peimine was administered in two doses (0.24 mg/kg and 0.48 mg/kg p.o) to examine its efficacy in curing breast cancer while tamoxifen was used as standard.

RESULTS

A reduction in tumour size was observed in the peimine-treated groups. Peimine can correct the changed blood cell count in addition to its anti-tumour activity. In peimine-treated rats, imbalanced immune marker IgE, serum oxidative marker, and tissue apoptotic markers like cytochrome c and calcium level were shown to be restored significantly.

CONCLUSION

Our findings imply that quinine has beneficial effects as an anti-neoplastic medication for breast cancer, most likely through its apoptotic activity. More research is necessary to thoroughly understand their mechanisms of action, ideal dose, and potential side effects.

Antioxidant Enzymes and Their Potential Use in Breast Cancer Treatment

According to the World Health Organization (WHO), breast cancer (BC) is the deadliest and the most common type of cancer worldwide in women. Several factors associated with BC exert their effects by modulating the state of stress. They can induce genetic mutations or alterations in cell growth, encouraging neoplastic development and the production of reactive oxygen species (ROS). ROS are able to activate many signal transduction pathways, producing an inflammatory environment that leads to the suppression of programmed cell death and the promotion of tumor proliferation, angiogenesis, and metastasis; these effects promote the development and progression of malignant neoplasms. However, cells have both non-enzymatic and enzymatic antioxidant systems that protect them by neutralizing the harmful effects of ROS. In this sense, antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR), thioredoxin reductase (TrxR), and peroxiredoxin (Prx) protect the body from diseases caused by oxidative damage. In this review, we will discuss mechanisms through which some enzymatic antioxidants inhibit or promote carcinogenesis, as well as the new therapeutic proposals developed to complement traditional treatments.

Cellular Red-Ox system in health and disease: The latest update

Cells are continually exposed to reactive oxygen species (ROS) generated during cellular metabolism. Apoptosis, necrosis, and autophagy are biological processes involving a feedback cycle that causes ROS molecules to induce oxidative stress. To adapt to ROS exposure, living cells develop various defense mechanisms to neutralize and use ROS as a signaling molecule. The cellular redox networks combine signaling pathways that regulate cell metabolism, energy, cell survival, and cell death. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) are essential antioxidant enzymes that are required for scavenging ROS in various cell compartments and response to stressful situations. Among the non-enzymatic defenses, vitamin C, glutathione (GSH), polyphenols, carotenoids, vitamin E, etc., are also essential. This review article describes how ROS are produced as byproducts of oxidation/reduction (redox) processes and how the antioxidants defense system is directly or indirectly engaged in scavenging ROS. In addition, we used computational methods to determine the comparative profile of binding energies of several antioxidants with antioxidant enzymes. The computational analysis demonstrates that antioxidants with a high affinity for antioxidant enzymes regulate their structures.

To Be or Not to Be? Are Reactive Oxygen Species, Antioxidants, and Stress Signalling Universal Determinants of Life or Death?

In the environmental and organism context, oxidative stress is complex and unavoidable. Organisms simultaneously cope with a various combination of stress factors in natural conditions. For example, excess light stress is accompanied by UV stress, heat shock stress, and/or water stress. Reactive oxygen species (ROS) and antioxidant molecules, coordinated by electrical signalling (ES), are an integral part of the stress signalling network in cells and organisms. They together regulate gene expression to redirect energy to growth, acclimation, or defence, and thereby, determine cellular stress memory and stress crosstalk. In plants, both abiotic and biotic stress increase energy quenching, photorespiration, stomatal closure, and leaf temperature, while toning down photosynthesis and transpiration. Locally applied stress induces ES, ROS, retrograde signalling, cell death, and cellular light memory, then acclimation and defence responses in the local organs, whole plant, or even plant community (systemic acquired acclimation, systemic acquired resistance, network acquired acclimation). A simplified analogy can be found in animals where diseases vs. fitness and prolonged lifespan vs. faster aging, are dependent on mitochondrial ROS production and ES, and body temperature is regulated by sweating, temperature-dependent respiration, and gene regulation. In this review, we discuss the universal features of stress factors, ES, the cellular production of ROS molecules, ROS scavengers, hormones, and other regulators that coordinate life and death.

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.

An in silico comparative transcriptome analysis identifying hub lncRNAs and mRNAs in brain metastatic small cell lung cancer (SCLC)

Small cell lung cancer (SCLC) is a particularly lethal subtype of lung cancer. Metastatic lung tumours lead to most deaths from lung cancer. Predicting and preventing tumour metastasis is crucially essential for patient survivability. Hence, in the current study, we focused on a comprehensive analysis of lung cancer patients' differentially expressed genes (DEGs) on brain metastasis cell lines. DEGs are analysed through KEGG and GO databases for the most critical biological processes and pathways for enriched DEGs. Additionally, we performed protein-protein interaction (PPI), GeneMANIA, and Kaplan-Meier survival analyses on our DEGs. This article focused on mRNA and lncRNA DEGs for LC patients with brain metastasis and underlying molecular mechanisms. The expression data was gathered from the Gene Expression Omnibus database (GSE161968). We demonstrate that 30 distinct genes are up-expressed in brain metastatic SCLC patients, and 31 genes are down-expressed. All our analyses show that these genes are involved in metastatic SCLC. PPI analysis revealed two hub genes (CAT and APP). The results of this article present three lncRNAs, Including XLOC_l2_000941, LOC100507481, and XLOC_l2_007062, also notable mRNAs, have a close relation with brain metastasis in lung cancer and may have a role in the epithelial-mesenchymal transition (EMT) in tumour cells.

Singlet Oxygen, Photodynamic Therapy, and Mechanisms of Cancer Cell Death

Photodynamic therapy (PDT) can be developed into an important arsenal against cancer; it is a minimally invasive therapy, which is used in the treatment or/and palliation of a variety of cancers and benign diseases. The removal of cancerous tissue is achieved with the use of photosensitizer and a light source, which excites the photosensitizer. This excitation causes the photosensitizer to generate singlet oxygen and other reactive oxygen species. PDT has been used in several types of cancers including nonmelanoma skin cancer, bladder cancer, esophageal cancer, head and neck cancer, and non-small cell lung cancer (NSCLC). Although it is routinely used in nonmelanoma skin cancer, it has not been widely adopted in other solid cancers due to a lack of clinical data showing the superiority of PDT over other forms of treatment. Singlet oxygen used in PDT can alter the activity of the catalase, which induces immunomodulation through HOCl signaling. The singlet oxygen can induce apoptosis through both the extrinsic and intrinsic pathways. The extrinsic pathway of apoptosis starts with the activation of the Fas receptor by singlet oxygen that leads to activation of the caspase-7 and caspase-3. In the case of the intrinsic pathway, disruption caused by singlet oxygen in the mitochondria membrane leads to the release of cytochrome c, which binds with APAF-1 and procaspase-9, forming a complex, which activates caspase-3. Mechanisms of PDT action can vary according to organelles affected. In the plasma membrane, membrane disruption is caused by the oxidative stress leading to the intake of calcium ions, which causes swelling and rupture of cells due to excess intake of water, whereas disruption of lysosome causes the release of the cathepsins B and D, which cleave Bid into tBid, which changes the mitochondrial outer membrane permeability (MOMP). Oxidative stress causes misfolding of protein in the endoplasmic reticulum. When misfolding exceeds the threshold, it triggers unfolding protein response (UPR), which leads to activation of caspase-9 and caspase-3. Finally, the activation of p38 MAPK works as an alternative pathway for the induction of MOMP.

FOXO3a-ROS pathway is involved in androgen-induced proliferation of prostate cancer cell

Background

Although FOXO3a can inhibit the cell proliferation of prostate cancer, its relationship with reactive oxygen species (ROS) in prostate cancer (PCa) has not been reported.

Methods

We analyzed the correlation between the expression of FOXO3a and the antioxidant enzyme catalase in prostate cancer with the TCGA and GEPIA databases. We also constructed a PPI network of FOXO3a via the STRING database. The mRNA and protein expression of FOXO3a and catalase were detected by qRT-PCR or western blotting in LNCaP and 22RV1 cells treated with DHT, R1881, or Enzalutamide. The effects of FOXO3a on catalase expression were tested by over-expressing or knocking down FOXO3a in LNCaP cells. Furthermore, the catalase activity and ROS level were detected in LNCaP cells treated with DHT. Cell proliferation and ROS were also analyzed in LNCaP which was treated with antioxidant.

Results

Results showed that the catalase expression was down-regulated in prostate cancer. A positive correlation between FOXO3a and catalase existed. DHT treatment could significantly reduce FOXO3a and catalase expression at mRNA and protein level in LNCaP cells. Catalase expression partly depended on FOXO3a as over-expression and knockdown of FOXO3a could result in the expresssion change of catalase. DHT treatment was found to inhibit catalase activity and increase ROS level in prostate cancer cell. Our study also demonstrated that antioxidant treatment reduced DHT-induced proliferation and ROS production in prostate cancer cell.

Conclusions

We discovered a novel mechanism by which DHT promotes prostate cancer cell proliferation via suppressing catalase activity and activating ROS signaling via a FOXO3a dependent manner.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-022-01020-9.

Catalase Overexpression Drives an Aggressive Phenotype in Glioblastoma

Glioblastoma remains the deadliest form of brain cancer, largely because these tumors become resistant to standard of care treatment with radiation and chemotherapy. Intracellular production of reactive oxygen species (ROS) is necessary for chemo- and radiotherapy-induced cytotoxicity. Here, we assessed whether antioxidant catalase (CAT) affects glioma cell sensitivity to temozolomide and radiation. Using The Cancer Genome Atlas database, we found that CAT mRNA expression is upregulated in glioma tumor tissue compared with non-tumor tissue, and the level of expression negatively correlates with the overall survival of patients with high-grade glioma. In U251 glioma cells, CAT overexpression substantially decreased the basal level of hydrogen peroxide, enhanced anchorage-independent cell growth, and facilitated resistance to the chemotherapeutic drug temozolomide and ionizing radiation. Importantly, pharmacological inhibition of CAT activity reduced the proliferation of glioma cells isolated from patient biopsy samples. Moreover, U251 cells overexpressing CAT formed neurospheres in neurobasal medium, whereas control cells did not, suggesting that the radio- and chemoresistance conferred by CAT may be due in part to the enrichment of glioma stem cell populations. Finally, CAT overexpression significantly decreased survival in an orthotopic mouse model of glioma. These results demonstrate that CAT regulates chemo- and radioresistance in human glioma.

Catalase Overexpression Drives an Aggressive Phenotype in Glioblastoma

Glioblastoma remains the deadliest form of brain cancer, largely because these tumors become resistant to standard of care treatment with radiation and chemotherapy. Intracellular production of reactive oxygen species (ROS) is necessary for chemo- and radiotherapy-induced cytotoxicity. Here, we assessed whether antioxidant catalase (CAT) affects glioma cell sensitivity to temozolomide and radiation. Using The Cancer Genome Atlas database, we found that CAT mRNA expression is upregulated in glioma tumor tissue compared with non-tumor tissue, and the level of expression negatively correlates with the overall survival of patients with high-grade glioma. In U251 glioma cells, CAT overexpression substantially decreased the basal level of hydrogen peroxide, enhanced anchorage-independent cell growth, and facilitated resistance to the chemotherapeutic drug temozolomide and ionizing radiation. Importantly, pharmacological inhibition of CAT activity reduced the proliferation of glioma cells isolated from patient biopsy samples. Moreover, U251 cells overexpressing CAT formed neurospheres in neurobasal medium, whereas control cells did not, suggesting that the radio- and chemoresistance conferred by CAT may be due in part to the enrichment of glioma stem cell populations. Finally, CAT overexpression significantly decreased survival in an orthotopic mouse model of glioma. These results demonstrate that CAT regulates chemo- and radioresistance in human glioma.

Vitamin C (Ascorbate) and Redox Topics in Cancer

Significance: Vitamin C (ascorbate), in regard to its effectiveness against malignancies, has had a controversial history in cancer treatment. It has been shown that in vitro and in vivo anticancer efficacy of ascorbate relies on its pro-oxidant effect mainly from an increased generation of reactive oxygen species (ROS). A growing understanding of its anticancer activities and pharmacokinetic properties has prompted scientists to re-evaluate the significance of ascorbate in cancer treatment. Recent Advances: A recent resurge in ascorbate research emerged after discovering that, at high doses, ascorbate preferentially kills Kirsten-Ras (K-ras)- and B-raf oncogene (BRAF)-mutant cancer cells. In addition, some of the main hallmarks of cancer cells, such as redox homeostasis and oxygen-sensing regulation (through inhibition of hypoxia-inducible factor-1 alpha [HIF-1α] activity), are affected by vitamin C. Critical Issues: Currently, there is no clear consensus from the literature in regard to the beneficial effects of antioxidants. Results from both human and animal studies provide no clear evidence about the benefit of antioxidant treatment in preventing or suppressing cancer development. Since pro-oxidants may affect both normal and tumor cells, the extremely low toxicity of ascorbate represents a main advantage. This guarantees the safe inclusion of ascorbate in clinical protocols to treat cancer patients. Future Directions: Current research could focus on elucidating the wide array of reactions between ascorbate and reactive species, namely ROS, reactive nitrogen species as well as reactive sulfide species, and their intracellular molecular targets. Unraveling these mechanisms could allow researchers to assess what could be the optimal combination of ascorbate with standard treatments.

LSD1 Facilitates Pro-Inflammatory Polarization of Macrophages by Repressing Catalase

The increased level of hydrogen peroxide accompanies some modes of macrophage specification and is linked to ROS-based antimicrobial activity of these phagocytes. In this study, we show that activation of toll-like receptors with bacterial components such as LPS is accompanied by the decline in transcription of hydrogen peroxide decomposing enzyme-catalase, suppression of which facilitates the polarization of human macrophages towards the pro-inflammatory phenotype. The chromatin remodeling at the CAT promoter involves LSD1 and HDAC1, but activity of the first enzyme defines abundance of the two proteins on chromatin, histone acetylation status and the CAT transcription. LSD1 inhibition prior to macrophage activation with LPS prevents CAT repression by enhancing the LSD1 and interfering with the HDAC1 recruitment to the gene promoter. The maintenance of catalase level with LSD1 inhibitors during M1 polarization considerably limits LPS-triggered expression of some pro-inflammatory cytokines and markers such as IL1β, TNFα, COX2, CD14, TLR2, and IFNAR, but the effect of LSD1 inhibitors is lost upon catalase deficiency. Summarizing, activity of LSD1 allows for the CAT repression in LPS stimulated macrophages, which negatively controls expression of some key pro-inflammatory markers. LSD1 inhibitors can be considered as possible immunosuppressive drugs capable of limiting macrophage M1 specialization.

Regulation of Mitochondrial Dynamics in Parkinson's Disease-Is 2-Methoxyestradiol a Missing Piece?

Mitochondria, as "power house of the cell", are crucial players in cell pathophysiology. Beyond adenosine triphosphate (ATP) production, they take part in a generation of reactive oxygen species (ROS), regulation of cell signaling and cell death. Dysregulation of mitochondrial dynamics may lead to cancers and neurodegeneration; however, the fusion/fission cycle allows mitochondria to adapt to metabolic needs of the cell. There are multiple data suggesting that disturbed mitochondrial homeostasis can lead to Parkinson's disease (PD) development. 2-methoxyestradiol (2-ME), metabolite of 17β-estradiol (E2) and potential anticancer agent, was demonstrated to inhibit cell growth of hippocampal HT22 cells by means of nitric oxide synthase (NOS) production and oxidative stress at both pharmacologically and also physiologically relevant concentrations. Moreover, 2-ME was suggested to inhibit mitochondrial biogenesis and to be a dynamic regulator. This review is a comprehensive discussion, from both scientific and clinical point of view, about the influence of 2-ME on mitochondria and its plausible role as a modulator of neuron survival.

Selective Targeting of Cancerous Mitochondria and Suppression of Tumor Growth Using Redox-Active Treatment Adjuvant

Redox-active substances and their combinations, such as of quinone/ascorbate and in particular menadione/ascorbate (M/A; also named Apatone®), attract attention with their unusual ability to kill cancer cells without affecting the viability of normal cells as well as with the synergistic anticancer effect of both molecules. So far, the primary mechanism of M/A-mediated anticancer effects has not been linked to the mitochondria. The aim of our study was to clarify whether this “combination drug” affects mitochondrial functionality specifically in cancer cells. Studies were conducted on cancer cells (Jurkat, Colon26, and MCF7) and normal cells (normal lymphocytes, FHC, and MCF10A), treated with different concentrations of menadione, ascorbate, and/or their combination (2/200, 3/300, 5/500, 10/1000, and 20/2000 μM/μM of M/A). M/A exhibited highly specific and synergistic suppression on cancer cell growth but without adversely affecting the viability of normal cells at pharmacologically attainable concentrations. In M/A-treated cancer cells, the cytostatic/cytotoxic effect is accompanied by (i) extremely high production of mitochondrial superoxide (up to 15-fold over the control level), (ii) a significant decrease of mitochondrial membrane potential, (iii) a decrease of the steady-state levels of ATP, succinate, NADH, and NAD⁺, and (iv) a decreased expression of programed cell death ligand 1 (PD-L1)—one of the major immune checkpoints. These effects were dose dependent. The inhibition of NQO1 by dicoumarol increased mitochondrial superoxide and sensitized cancer cells to M/A. In normal cells, M/A induced relatively low and dose-independent increase of mitochondrial superoxide and mild oxidative stress, which seems to be well tolerated. These data suggest that all anticancer effects of M/A result from a specific mechanism, tightly connected to the mitochondria of cancer cells. At low/tolerable doses of M/A (1/100-3/300 μM/μM) attainable in cancer by oral and parenteral administration, M/A sensitized cancer cells to conventional anticancer drugs, exhibiting synergistic or additive cytotoxicity accompanied by impressive induction of apoptosis. Combinations of M/A with 13 anticancer drugs were investigated (ABT-737, barasertib, bleomycin, BEZ-235, bortezomib, cisplatin, everolimus, lomustine, lonafarnib, MG-132, MLN-2238, palbociclib, and PI-103). Low/tolerable doses of M/A did not induce irreversible cytotoxicity in cancer cells but did cause irreversible metabolic changes, including: (i) a decrease of succinate and NADH, (ii) depolarization of the mitochondrial membrane, and (iii) overproduction of superoxide in the mitochondria of cancer cells only. In addition, M/A suppressed tumor growth in vivo after oral administration in mice with melanoma and the drug downregulated PD-L1 in melanoma cells. Experimental data suggest a great potential for beneficial anticancer effects of M/A through increasing the sensitivity of cancer cells to conventional anticancer therapy, as well as to the immune system, while sparing normal cells. We hypothesize that M/A-mediated anticancer effects are triggered by redox cycling of both substances, specifically within dysfunctional mitochondria. M/A may also have a beneficial effect on the immune system, making cancer cells “visible” and more vulnerable to the native immune response.

Nutrigenomics and Breast Cancer: State-of-Art, Future Perspectives and Insights for Prevention

Proper nutrition plays a major role in preventing diseases and, therefore, nutritional interventions constitute crucial strategies in the field of Public Health. Nutrigenomics and nutriproteomics are arising from the integration of nutritional, genomics and proteomics specialties in the era of postgenomics medicine. In particular, nutrigenomics and nutriproteomics focus on the interaction between nutrients and the human genome and proteome, respectively, providing insights into the role of diet in carcinogenesis. Further omics disciplines, like metabonomics, interactomics and microbiomics, are expected to provide a better understanding of nutrition and its underlying factors. These fields represent an unprecedented opportunity for the development of personalized diets in women at risk of developing breast cancer.