Matairesinol inhibits angiogenesis via suppression of mitochondrial reactive oxygen species

Matairesinol repolarizes M2 macrophages to M1 phenotype to induce apoptosis in triple-negative breast cancer cells

OBJECTIVE

Triple-Negative Breast Cancer (TNBC), the most challenging subtype of Breast Cancer (BC), currently lacks targeted therapy, presenting a significant therapeutic gap in its management. Tumor Associated Macrophages (TAMs) play a significant role in TNBC progression and could be targeted by repolarizing them from M2 to M1 phenotype. Matairesinol (MAT), a plant lignan, has been shown to exhibit anticancer, anti-inflammatory and immunomodulatory activities. In this study, we explored how MAT-induced repolarization of THP-1-derived M2 macrophages towards the M1 phenotype, which could effectively target the TNBC cell line, MDA-MB-231.

METHODS

The differential expression of genes in THP-1-derived macrophages at mRNA levels was evaluated by RNAseq assay. An inverted microscope equipped with a CMOS camera was utilized to capture the morphological variations in THP-1 cells and THP-1-derived macrophages. Relative mRNA expression of M1 and M2 specific marker genes was quantified by qRT-PCR. Cell viability and induction of apoptosis were evaluated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethylbenzimidazolylcarbocyanine iodide (JC-1 dye) assays, respectively.

RESULTS

MAT reduced the viability of M2a and M2d macrophages and repolarized them to M1 phenotype. Conditioned medium (CM) from MAT-treated M2a and M2d macrophages significantly reduced the viability of TNBC cells by apoptosis.

CONCLUSION

Targeting M2 macrophages is an important strategy to regulate cancer progression. Our study provides evidence that MAT may be a promising drug candidate for developing novel anti-TNBC therapy. However, further studies are warranted to thoroughly elucidate the molecular mechanism of action of MAT and evaluate its therapeutic potential in TNBC in vitro and in vivo models.

Novel systems biology experimental pipeline reveals matairesinol's antimetastatic potential in prostate cancer: an integrated approach of network pharmacology, bioinformatics, and experimental validation

Matairesinol (MAT), a plant lignan renowned for its anticancer properties in hormone-sensitive cancers like breast and prostate cancers, presents a promising yet underexplored avenue in the treatment of metastatic prostate cancer (mPC). To elucidate its specific therapeutic targets and mechanisms, our study adopted an integrative approach, amalgamating network pharmacology (NP), bioinformatics, GeneMANIA-based functional association (GMFA), and experimental validation. By mining online databases, we identified 27 common targets of mPC and MAT, constructing a MAT-mPC protein-protein interaction network via STRING and pinpointing 11 hub targets such as EGFR, AKT1, ERBB2, MET, IGF1, CASP3, HSP90AA1, HIF1A, MMP2, HGF, and MMP9 with CytoHuba. Utilizing DAVID, Gene Ontology (GO) analysis highlighted metastasis-related processes such as epithelial-mesenchymal transition, positive regulation of cell migration, and key Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways, including cancer, prostate cancer, PI3K-Akt, and MAPK signaling, while the web resources such as UALCAN and GEPIA2 affirmed the clinical significance of the top 11 hub targets in mPC patient survival analysis and gene expression patterns. Our innovative GMFA enrichment method further enriched network pharmacology findings. Molecular docking analyses demonstrated substantial interactions between MAT and 11 hub targets. Simulation studies confirmed the stable interactions of MAT with selected targets. Experimental validation in PC3 cells, employing quantitative real-time reverse-transcription PCR and various cell-based assays, corroborated MAT's antimetastatic effects on mPC. Thus, this exhaustive NP analysis, complemented by GMFA, molecular docking, molecular dynamics simulations, and experimental validations, underscores MAT's multifaceted role in targeting mPC through diverse therapeutic avenues. Nevertheless, comprehensive in vitro validation is imperative to solidify these findings.

HPLC-ESI/MS-MS metabolic profiling of white pitaya fruit and cytotoxic potential against cervical cancer: Comparative studies, synergistic effects, and molecular mechanistic approaches

Natural approach became a high demand for the prevention and treatment of such diseases for their proven safety and efficacy. This study is aimed to perform comparative phytochemical analysis of white pitaya (Hylocereus undatus) peel, pulp and seed extracts via determination of total flavonoid content, phenolic content, and antioxidant capacity, coupled with HPLC-ESI/MS-MS analysis. Further, we evaluated the synergistic cytotoxic potential with Cisplatin against cervical cancer cells with investigation of underlying mechanism. The highest content of phenolics and antioxidants were found in both seed and peel extracts. The HPLC-ESI/MS-MS revealed identification of flavonoids, phenolic acids, anthocyanin glycosides, lignans, stilbenes, and coumarins. The cytotoxicity effects were evaluated by MTT assay against prostate, breast and cervical (HeLa) and Vero cell lines. The seed and peel extracts showed remarkable cytotoxic effect against all tested cell lines. Moreover, the selectivity index confirmed high selectivity of pitaya extracts to cancer cells and safety on normal cells. The combined therapy with Cisplatin effectively enhanced its efficacy and optimized the treatment outcomes, through the apoptotic ability of pitaya extracts in HeLa cells, as evaluated by flow cytometry. Besides, RT-PCR and western blotting analysis showed downregulation of Bcl-2 and overexpression of P53, BAX among HeLa cells treated with pitaya extracts, which eventually activated apoptosis process. Thus, pitaya extract could be used as adjuvant therapy with cisplatin for treatment of cervical cancer. Furthermore, in-vivo extensive studies on the seed and peel extracts, and their compounds are recommended to gain more clarification about the required dose, and side effects.

Marine-Derived Leads as Anticancer Candidates by Disrupting Hypoxic Signaling through Hypoxia-Inducible Factors Inhibition

The inadequate vascularization seen in fast-growing solid tumors gives rise to hypoxic areas, fostering specific changes in gene expression that bolster tumor cell survival and metastasis, ultimately leading to unfavorable clinical prognoses across different cancer types. Hypoxia-inducible factors (HIF-1 and HIF-2) emerge as druggable pivotal players orchestrating tumor metastasis and angiogenesis, thus positioning them as prime targets for cancer treatment. A range of HIF inhibitors, notably natural compounds originating from marine organisms, exhibit encouraging anticancer properties, underscoring their significance as promising therapeutic options. Bioprospection of the marine environment is now a well-settled approach to the discovery and development of anticancer agents that might have their medicinal chemistry developed into clinical candidates. However, despite the massive increase in the number of marine natural products classified as 'anticancer leads,' most of which correspond to general cytotoxic agents, and only a few have been characterized regarding their molecular targets and mechanisms of action. The current review presents a critical analysis of inhibitors of HIF-1 and HIF-2 and hypoxia-selective compounds that have been sourced from marine organisms and that might act as new chemotherapeutic candidates or serve as templates for the development of structurally similar derivatives with improved anticancer efficacy.

Isolation and Identification of Allelopathic Substances from Forsythia suspensa Leaves, and Their Metabolism and Activity

The fruit of Forsythia suspensa (Thunb.) Vahl has been used in traditional Chinese medicine as "Forsythiae fructus". The species is also grown in parks and gardens, and on streets and building lots, as an ornamental plant, but it requires pruning. In this study, the allelopathic activity and allelopathic substances in the leaves of pruned branches of F. suspensa were investigated to determine any potential application. The leaf extracts of F. suspensa showed growth inhibitory activity against three weed species; Echinochloa crus-galli, Lolium multiflorum, and Vulpia myuros. Two allelopathic substances in the extracts were isolated through the bioassay-guided purification process, and identified as (-)-matairesinol and (-)-arctigenin. (-)-Matairesinol and (-)-arctigenin, which showed significant growth inhibitory activity at concentrations greater than 0.3 mM in vitro. The inhibitory activity of (-)-arctigenin was greater than that of (-)-matairesinol. However, both compounds were more active than (+)-pinolesinol which is their precursor in the biosynthetic pathway. The investigation suggests that F. suspensa leaves are allelopathic, and (-)-matairesinol and (-)-arctigenin may contribute to the growth inhibitory activities. Therefore, the leaves of the pruned branches can be applied as a weed management strategy in some agricultural practices such as using the leaf extracts in a foliar spray and the leaves in a soil mixture, thereby reducing the dependency on synthetic herbicides in the crop cultivation and contributing to developing eco-friendly agriculture.

Deciphering the prognostic significance of anoikis-related lncRNAs in invasive breast cancer: from comprehensive bioinformatics analysis to functional experimental validation

The global prevalence of breast cancer necessitates the development of innovative prognostic markers and therapeutic strategies. This study investigated the prognostic implications of anoikis-related long non-coding RNAs (ARLs) in invasive breast cancer (IBC), which is an area that has not been extensively explored. By integrating the RNA sequence transcriptome and clinical data from The Cancer Genome Atlas (TCGA) database and employing advanced regression analyses, we devised a novel prognostic model based on ARL scores. ARL scores correlated with diverse clinicopathological parameters, cellular pathways, distinct mutation patterns, and immune responses, thereby affecting both immune cell infiltration and anticipated responses to chemotherapy and immunotherapy. Additionally, the overexpression of a specific lncRNA, AL133467.1, significantly impeded the proliferation and migration, as well as possibly the anoikis resistance of breast cancer cells. These findings highlight the potential of the ARL signature as a robust prognostic tool and a promising basis for personalized IBC treatment strategies.

Chemical characteristics of Rhodiola Crenulata and its mechanism in acute mountain sickness using UHPLC-Q-TOF-MS/MS combined with network pharmacology analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Rhodiola crenulata (Hook.f. & Thomson) H.Ohba has a long history of clinical application for the prevention and treatment of acute mountain sickness (AMS) in traditional Chinese medicine. However, gaps in knowledge still exist in understanding the underlying mechanisms of Rhodiola crenulata against AMS.

AIMS

To address this problem, a comprehensive method was established by combining UHPLC-Q-TOF-MS/MS analysis and network pharmacology.

MATERIALS AND METHODS

The ingredients of Rhodiola crenulata were comprehensively analyzed using UHPLC-Q-TOF-MS/MS method. On this basis, a network pharmacology method incorporated target prediction, protein-protein interaction network, gene enrichment analysis and components-targets-pathways network was performed. Finally, the possible mechanisms were verified through molecular docking, in vitro and in vivo experiments.

RESULTS

A total of 106 constituents of Rhodiola crenulata were charactered via UHPLC-Q-TOF-MS/MS. The 98 potentially active compounds out of 106 were screened and corresponded to 53 anti-AMS targets. Gene enrichment analysis revealed that hypoxia and inflammation related genes may be the central factors for Rhodiola crenulata to modulate AMS. Molecular docking revealed that TNF, VEGFA and HIF-1α had high affinities to Rhodiola crenulata compounds. Subsequently, Rhodiola crenulata extract was indicated to inhibit the protein expression level of TNF in hypoxia induced H9c2 cells. Lastly, Rhodiola crenulata extract was further verified to ameliorate heart injury and decreased the heart levels of TNF, VEGFA and HIF-1α in acute hypoxia-induced rats.

CONCLUSIONS

This study used UHPLC-Q-TOF-MS/MS analysis and a network pharmacology to provide an important reference for revealing the potential mechanism of Rhodiola crenulata in the prevention and treatment of AMS.

Matairesinol Induces Mitochondrial Dysfunction and Exerts Synergistic Anticancer Effects with 5-Fluorouracil in Pancreatic Cancer Cells

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive types of cancer and exhibits a devastating 5-year survival rate. The most recent procedure for the treatment of PDAC is a combination of several conventional chemotherapeutic agents, termed FOLFIRINOX, that includes irinotecan, leucovorin, oxaliplatin, and 5-fluorouracil (5-FU). However, ongoing treatment using these agents is challenging due to their severe side effects and limitations on the range of patients available for PDAC. Therefore, safer and more innovative anticancer agents must be developed. The anticarcinoma activity of matairesinol that can be extracted from seagrass has been reported in various types of cancer, including prostate, breast, cervical, and pancreatic cancer. However, the molecular mechanism of effective anticancer activity of matairesinol against pancreatic cancer remains unclear. In the present study, we confirmed the inhibition of cell proliferation and progression induced by matairesinol in representative human pancreatic cancer cell lines (MIA PaCa-2 and PANC-1). Additionally, matairesinol triggers apoptosis and causes mitochondrial impairment as evidenced by the depolarization of the mitochondrial membrane, disruption of calcium, and suppression of cell migration and related intracellular signaling pathways. Finally, matairesinol exerts a synergistic effect with 5-FU, a standard anticancer agent for PDAC. These results demonstrate the therapeutic potential of matairesinol in the treatment of PDAC.

Lignans as Pharmacological Agents in Disorders Related to Oxidative Stress and Inflammation: Chemical Synthesis Approaches and Biological Activities

Plant lignans exhibit a wide range of biological activities, which makes them the research objects of potential use as therapeutic agents. They provide diverse naturally-occurring pharmacophores and are available for production by chemical synthesis. A large amount of accumulated data indicates that lignans of different structural groups are apt to demonstrate both anti-inflammatory and antioxidant effects, in many cases, simultaneously. In this review, we summarize the comprehensive knowledge about lignan use as a bioactive agent in disorders associated with oxidative stress and inflammation, pharmacological effects in vitro and in vivo, molecular mechanisms underlying these effects, and chemical synthesis approaches. This article provides an up-to-date overview of the current data in this area, available in PubMed, Scopus, and Web of Science databases, screened from 2000 to 2022.

Dietary lignans, plasma enterolactone levels, and metabolic risk in men: exploring the role of the gut microbiome

BACKGROUND

The conversion of plant lignans to bioactive enterolignans in the gastrointestinal tract is mediated through microbial processing. The goal of this study was to examine the relationships between lignan intake, plasma enterolactone concentrations, gut microbiome composition, and metabolic risk in free-living male adults.

RESULTS

In 303 men participating in the Men's Lifestyle Validation Study (MLVS), lignan intake was assessed using two sets of 7-day diet records, and gut microbiome was profiled through shotgun sequencing of up to 2 pairs of fecal samples (n = 911). A score was calculated to summarize the abundance of bacteria species that were significantly associated with plasma enterolactone levels. Of the 138 filtered species, plasma enterolactone levels were significantly associated with the relative abundances of 18 species at FDR < 0.05 level. Per SD increment of lignan intake was associated with 20.7 nM (SEM: 2.3 nM) higher enterolactone concentrations among participants with a higher species score, whereas the corresponding estimate was 4.0 nM (SEM: 1.7 nM) among participants with a lower species score (P for interaction < 0.001). A total of 12 plasma metabolites were also significantly associated with these enterolactone-predicting species. Of the association between lignan intake and metabolic risk, 19.8% (95%CI: 7.3%-43.6%) was explained by the species score alone, 54.5% (95%CI: 21.8%-83.7%) by both species score and enterolactone levels, and 79.8% (95%CI: 17.7%-98.6%) by further considering the 12 plasma metabolites.

CONCLUSION

We identified multiple gut bacteria species that were enriched or depleted at higher plasma levels of enterolactone in men. These species jointly modified the associations of lignan intake with plasma enterolactone levels and explained the majority of association between lignan intake and metabolic risk along with enterolactone levels and certain plasma metabolites.

Matairesinol exerts anti-inflammatory and antioxidant effects in sepsis-mediated brain injury by repressing the MAPK and NF-κB pathways through up-regulating AMPK

Brain injury is a familiar complication of severe sepsis, in which excessive inflammation and oxidative stress are the main mechanisms leading to acute brain injury. Here, we focus on probing the function and mechanism of Matairesinol (Mat) in sepsis-mediated brain injury. We established a rat sepsis model by cecal ligation and perforation (CLP) and constructed an in vitro sepsis model by treating neurons and microglia with lipopolysaccharide (LPS). Rats and cells were treated with varying concentrations of Mat, and the changes of neural function, neuronal apoptosis, microglial activation, neuroinflammation and the expression of oxidative stress factors in brain tissues were examined. Additionally, the activation of the MAPK, NF-κB and AMPK pathways in brain tissues and cells was evaluated by Western blot (WB) and/or immunohistochemistry (IHC). Our findings illustrated that Mat improved neuronal apoptosis and weakened microglial activation in CLP rats. Meanwhile, Mat hampered the expression of pro-inflammatory factors (TNF-α, IL-1β, IL-6, IFN-γ, IL-8, and MCP1) and facilitated the contents of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in brain tissues and microglia. Mechanistically, Mat concentration-dependently dampened the phosphorylation of MAPK, JNK and NF-κB in CLP rats and LPS-stimulated microglia and up-regulated Nrf2 and HO-1. Besides, Mat facilitated the AMPK expression. Meanwhile, Compound C, a specific inhibitor of the AMPK pathway, substantially reduced the neuronal protection and anti-inflammatory effects mediated by Mat. Overall, Mat exerts anti-inflammatory and anti-oxidative stress effects by up-regulating AMPK, thereby ameliorating sepsis-mediated brain injury.

Matairesinol exerts anti-inflammatory and antioxidant effects in sepsis-mediated brain injury by repressing the MAPK and NF-κB pathways through up-regulating AMPK

Brain injury is a familiar complication of severe sepsis, in which excessive inflammation and oxidative stress are the main mechanisms leading to acute brain injury. Here, we focus on probing the function and mechanism of Matairesinol (Mat) in sepsis-mediated brain injury. We established a rat sepsis model by cecal ligation and perforation (CLP) and constructed an in vitro sepsis model by treating neurons and microglia with lipopolysaccharide (LPS). Rats and cells were treated with varying concentrations of Mat, and the changes of neural function, neuronal apoptosis, microglial activation, neuroinflammation and the expression of oxidative stress factors in brain tissues were examined. Additionally, the activation of the MAPK, NF-κB and AMPK pathways in brain tissues and cells was evaluated by Western blot (WB) and/or immunohistochemistry (IHC). Our findings illustrated that Mat improved neuronal apoptosis and weakened microglial activation in CLP rats. Meanwhile, Mat hampered the expression of pro-inflammatory factors (TNF-α, IL-1β, IL-6, IFN-γ, IL-8, and MCP1) and facilitated the contents of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in brain tissues and microglia. Mechanistically, Mat concentration-dependently dampened the phosphorylation of MAPK, JNK and NF-κB in CLP rats and LPS-stimulated microglia and up-regulated Nrf2 and HO-1. Besides, Mat facilitated the AMPK expression. Meanwhile, Compound C, a specific inhibitor of the AMPK pathway, substantially reduced the neuronal protection and anti-inflammatory effects mediated by Mat. Overall, Mat exerts anti-inflammatory and anti-oxidative stress effects by up-regulating AMPK, thereby ameliorating sepsis-mediated brain injury.

Effects of in vitro exposure of sheep ovarian tissue to zearalenone and matairesinol on preantral follicles

The aim of this study was to evaluate the effect of 1 µmol/l zearalenone (ZEN) and 1 µmol/l matairesinol (MAT), alone or in combination, on the morphology of in vitro-cultured ovarian preantral follicles. Ovaries from four adult sheep were collected at a local slaughterhouse and fragmented, and the ovarian pieces were submitted to in vitro culture for 3 days in the presence or absence of the test compounds. The morphology of primordial and primary follicles was impaired by ZEN. The plant lignan MAT alone did not maintain the morphology of the ovarian follicles; its combination with ZEN counteracted the negative effects observed when follicles were cultured in the presence of the mycotoxin alone. However, MAT was not able to promote the in vitro development of the ovarian follicles.

Lignan Intake and Risk of Coronary Heart Disease

BACKGROUND

Evidence regarding lignan consumption in relation to coronary heart disease (CHD) risk remains limited and mixed.

OBJECTIVES

The aim of this study was to prospectively examine associations between lignan intake and CHD risk in U.S. men and women.

METHODS

We prospectively followed 214,108 men and women in 3 cohorts who did not have cardiovascular disease or cancer at baseline. Diet was repeatedly assessed using a validated food frequency questionnaire every 2-4 years since baseline.

RESULTS

During 5,517,225 person-years of follow-up, we documented 10,244 CHD cases, including 6,283 nonfatal myocardial infarction and 3,961 fatal CHD cases. In multivariable-adjusted analyses, comparing extreme quintiles, the pooled hazard ratios of CHD were 0.85 (95% CI: 0.79-0.92) for total lignans, 0.76 (95% CI: 0.71-0.82) for matairesinol, 0.87 (95% CI: 0.81-0.93) for secoisolariciresinol, 0.89 (95% CI: 0.83-0.95) for pinoresinol, and 0.89 (95% CI: 0.83-0.95) for lariciresinol (all P values for trend ≤0.003). Nonlinear relationships were found for total lignan, matairesinol, and secoisolariciresinol: the risk reduction plateaued at intakes above approximately 300 μg/d, 10 μg/d, and 100 μg/d, respectively (P < 0.01 for all nonlinearity). The inverse associations for total lignan intake appeared to be more apparent among participants with higher total fiber intake (P = 0.04 for interaction). In addition, lignan intake was more strongly associated with plasma concentrations of enterolactone when fiber intake was higher.

CONCLUSIONS

Increased long-term intake of lignans was associated with a significantly lower risk of total CHD in both men and women. Possible synergistic effects may exist between lignan and fiber intake in relation to CHD risk reduction, possibly through enhancing the production of enterolignans.

Gut microbiota-derived metabolites and risk of coronary artery disease: a prospective study among US men and women

BACKGROUND

Accumulating evidence has suggested that human gut microbiota metabolize certain dietary compounds and subsequently produce bioactive metabolites that may exert beneficial or harmful effects on coronary artery disease (CAD) risk.

OBJECTIVES

This study examined the joint association of 2 gut microbiota metabolites, enterolactone and trimethylamine N-oxide (TMAO), that originate from intake of plant-based foods and animal products, respectively, in relation to CAD risk.

METHODS

A prospective nested case-control study of CAD was conducted among participants who were free of diabetes, cardiovascular disease, and cancer in the Nurses' Health Study II and the Health Professionals Follow-up Study. Plasma concentrations of enterolactone and TMAO, as well as choline and L-carnitine, were assayed among 608 CAD case-control pairs.

RESULTS

A high enterolactone and low TMAO profile was associated with better diet quality, especially higher intake of whole grains and fiber and lower intake of red meats, as well as lower concentrations of plasma triglycerides and C-reactive protein. Participants with a high enterolactone/low TMAO profile had a significantly lower risk of CAD: the multivariate-adjusted OR was 0.58 (95% CI: 0.38, 0.90), compared with participants with a low enterolactone/high TMAO profile. No significant interaction between enterolactone and TMAO on CAD risk was observed. Neither TMAO nor enterolactone alone were associated with CAD risk in pooled analyses. In women, a higher enterolactone concentration was significantly associated with a 54% lower CAD risk (P trend = 0.03), although the interaction by sex was not significant.

CONCLUSIONS

Our results show that a profile characterized by high enterolactone and low TMAO concentrations in plasma is linked to a healthful dietary pattern and significantly associated with a lower risk of CAD. Overall, these data suggest that, compared with individual markers, multiple microbiota-derived metabolites may facilitate better differentiation of CAD risk and characterization of the relations between diet, microbiota, and CAD risk.

Matairesinol, an active constituent of HC9 polyherbal formulation, exhibits HDAC8 inhibitory and anticancer activity

Histone deacetylase 8 (HDAC8) has emerged as a promising drug target for cancer therapeutics development. HDAC8 has been reported to regulate cancer cell proliferation, invasion and promote metastasis through modulation of cell cycle associated proteins. Of late, phytocompounds have been demonstrated to exhibit anticancer and anti-HDAC8 activity. Here, we have shown the HDAC8 inhibitory potential of an active phytocompound from HC9 (herbal composition-9), a polyherbal anticancer formulation based on the traditional Ayurvedic drug, Stanya Shodhan Kashaya. HC9 was recently reported to exhibit anticancer activity against breast cancer cells through induction of cell cycle arrest, decrease in migration and invasion as well as regulation of inflammation and chromatin modulators. In silico studies such as molecular docking, molecular dynamics (MD) simulation and binding free energy analyses showed greater binding energy values and interaction stability of MA with HDAC8 compared to other phytocompounds of HC9. Interestingly, in vitro validation confirmed the anti-HDAC8 activity of MA. Further, in vitro studies showed that MA significantly decreased the viability of breast and prostate cancer cell lines, thereby confirming its anticancer potential.

Pathological and Pharmacological Roles of Mitochondrial Reactive Oxygen Species in Malignant Neoplasms: Therapies Involving Chemical Compounds, Natural Products, and Photosensitizers

Oxidative stress plays an important role in cellular processes. Consequently, oxidative stress also affects etiology, progression, and response to therapeutics in various pathological conditions including malignant tumors. Oxidative stress and associated outcomes are often brought about by excessive generation of reactive oxygen species (ROS). Accumulation of ROS occurs due to dysregulation of homeostasis in an otherwise strictly controlled physiological condition. In fact, intracellular ROS levels are closely associated with the pathological status and outcome of numerous diseases. Notably, mitochondria are recognized as the critical regulator and primary source of ROS. Damage to mitochondria increases mitochondrial ROS (mROS) production, which leads to an increased level of total intracellular ROS. However, intracellular ROS level may not always reflect mROS levels, as ROS is not only produced by mitochondria but also by other organelles such as endoplasmic reticulum and peroxisomes. Thus, an evaluation of mROS would help us to recognize the biological and pathological characteristics and predictive markers of malignant tumors and develop efficient treatment strategies. In this review, we describe the pathological significance of mROS in malignant neoplasms. In particular, we show the association of mROS-related signaling in the molecular mechanisms of chemically synthesized and natural chemotherapeutic agents and photodynamic therapy.

The role of mitochondria in angiogenesis

Angiogenesis extends pre-existing blood vessels to improve oxygen and nutrient delivery to inflamed or otherwise hypoxic tissues. Mitochondria are integral in this process, controlling cellular metabolism to regulate the proliferation, migration, and survival of endothelial cells which comprise the inner lining of blood vessels. Mitochondrial Complex III senses hypoxic conditions and generates mitochondrial reactive oxygen species which stabilize hypoxia-inducible factor (HIF-1α) protein. HIF-1α induces the transcription of the vegfa gene, allowing the translation of vascular endothelial growth factor protein, which interacts with mature and precursor endothelial cells, mobilizing them to form new blood vessels. This cascade can be inhibited at specific points by means of gene knockdown, enzyme treatment, and introduction of naturally occurring small molecules, providing insight into the relationship between mitochondria and angiogenesis. This review focuses on current knowledge of the overall role of mitochondria in controlling angiogenesis and outlines known inhibitors that have been used to elucidate this pathway which may be useful in future research to control angiogenesis in vivo.

De Novo transcriptome assembly (NGS) of Curcuma longa L. rhizome reveals novel transcripts related to anticancer and antimalarial terpenoids

Herbal remedies are increasingly being recognised in recent years as alternative medicine for a number of diseases including cancer. Curcuma longa L., commonly known as turmeric is used as a culinary spice in India and in many Asian countries has been attributed to lower incidences of gastrointestinal cancers. Curcumin, a secondary metabolite isolated from the rhizomes of this plant has been shown to have significant anticancer properties, in addition to antimalarial and antioxidant effects. We sequenced the transcriptome of the rhizome of the 3 varieties of Curcuma longa L. using Illumina reversible dye terminator sequencing followed by de novo transcriptome assembly. Multiple databases were used to obtain a comprehensive annotation and the transcripts were functionally classified using GO, KOG and PlantCyc. Special emphasis was given for annotating the secondary metabolite pathways and terpenoid biosynthesis pathways. We report for the first time, the presence of transcripts related to biosynthetic pathways of several anti-cancer compounds like taxol, curcumin, and vinblastine in addition to anti-malarial compounds like artemisinin and acridone alkaloids, emphasizing turmeric's importance as a highly potent phytochemical. Our data not only provides molecular signatures for several terpenoids but also a comprehensive molecular resource for facilitating deeper insights into the transcriptome of C. longa.

Reactive oxygen species regulate FSH-induced expression of vascular endothelial growth factor via Nrf2 and HIF1α signaling in human epithelial ovarian cancer

Follicle-stimulating hormone (FSH) and the FSH receptor contribute to tumor angiogenesis and are acknowledged risk factors for ovarian epithelial cancer (OEC). Accumulating evidence suggests that FSH can induce vascular endothelial growth factor (VEGF) and hypoxia inducible factor 1α (HIF1α) expression. We previously demonstrated that FSH induces reactive oxygen species (ROS) production and activates Nrf2 signaling. This study was performed to investigate whether FSH induces VEGF expression via a ROS-mediated Nrf2 signaling pathway. In the current study, OET cells were treated with FSH; dichlorofluorescein staining was used to determine ROS generation, western blotting was used to quantify Nrf2 expression and VEGF expression was measured using an ELISA. Nrf2 and HIF1α were knocked down using siRNAs to investigate the role of the Nrf2 and HIF1α signaling pathways in FSH-induced VEGF expression. The chromatin immunoprecipitation assay (ChIP) was used to determine HIF1α binding to the VEGF promoter. Finally, it was found that FSH induced ROS production and activated Nrf2 signaling; elimination of ROS or knockdown of Nrf2 blocked FSH-induced VEGF expression. Knockdown of Nrf2 impaired HIF1α signaling activation. Blockage of the FSH-ROS-Nrf2-HIF1α signaling pathway attenuated FSH-induced binding of HIF1α to the VEGF promoter. Collectively, this study indicates that ROS and aberrant expression of Nrf2 play an important role in FSH-induced angiogenesis in OEC, and provides insight into the mechanisms of FSH-induced VEGF expression. Elimination of ROS or inhibition of Nrf2 may represent potential therapeutic targets for the treatment of ovarian cancer.