Genistein induces apoptosis by the inactivation of the IGF-1R/p-Akt signaling pathway in MCF-7 human breast cancer cells

Different antitumor effects of quercetin, quercetin-3′-sulfate and quercetin-3-glucuronide in human breast cancer MCF-7 cells

This study was designed to investigate the tumor-inhibitory effects of quercetin (Que) and its water-soluble metabolites, quercetin-3′-sulfate (Q3′S) and quercetin-3-glucuronide (Q3G), as well as to make the molecular mechanism and structure-antitumor relationship clear.

Preclinical evaluation of the anti-tumor effects of the natural isoflavone genistein in two xenograft mouse models monitored by [18F]FDG, [18F]FLT, and [64Cu]NODAGA-cetuximab small animal PET

The natural phytoestrogen genistein is known as protein kinase inhibitor and tumor suppressor in various types of cancers. We studied its antitumor effect in two different xenograft models using positron emission tomography (PET) in vivo combined with ex vivo histology and nuclear magnetic resonance (NMR) metabolic fingerprinting.

In vitro study on anti-cancer properties of genistein in tongue cancer

Purpose

Tongue cancer is an extremely aggressive disease and is characterized by a poor prognosis. It is a complex disease to treat and current therapies have produced mediocre results with many side effects. Some facts suggest that natural essences can support traditional cancer therapy by carrying out a synergistic function with chemotherapy. Therefore, we evaluated the antitumor effects of genistein on tongue carcinoma cells.

Methods

Genistein 20, 50 and 100 µM were used for 24, 48 and 72 hours on 3 tongue carcinoma cell lines. xCELLigence system was used to evaluate the effects on cell adhesion, proliferation and to calculate IC₅₀ values. Both MTT assay and Trypan blue assay were used to evaluate alterations in cell viability, scratch assay for cell migration and Western blot analysis for expression of some proteins.

Results

Cell adhesion was inhibited especially between 20 and 50 µM of genistein treatment. Proliferation was reduced by 50% for treatments with 20 µM at 24 hours, with 20 or 50 µM at 48 and 50 µM at 72 hours (P<0.0001). Viability tests confirmed a proportional reduction in concentration of genistein and duration of treatments. Even cell migration was reduced significantly (P<0.001). Genistein down-regulates vitronectin, OCT4 and survivin.

Conclusion

This in vitro study clarifies the anti-tumor effect of genistein on tongue carcinoma. In vivo studies are needed to confirm these data and develop a suitable delivery system that is capable of acting directly on tumor.

Equol Enhances Apoptosis-inducing Activity of Genistein by Increasing Bax/Bcl-xL Expression Ratio in MCF-7 Human Breast Cancer Cells

Anticancer activities of soy isoflavones, such as genistein and equol, a bioactive metabolite of daidzein, have been extensively studied because of possible involvement in the prevention of breast cancer. However, their interactions still remain unclear. We investigated here whether cytotoxic activity of genistein was enhanced by equol, using estrogen receptor positive MCF-7, HER2-positive SK-BR-3, and triple-negative MDA-MB-468 cell lines. Although cytotoxicity of genistein did not significantly differ between three subtypes of breast cancer cells, cytotoxic activities of genistein were significantly enhanced in combination with 50 μM equol in MCF-7 cells, but not in SK-BR-3 and MDA-MB-468 cells. In fluorescence activated cell sorting (FACS) analyses, MCF-7 cells were arrested at the G2/M by genistein but at G1/S by equol. Combination treatment arrested cells at G2/M but abolished equol-induced G1 block, indicating an antagonistic activity of genistein against equol in cell-cycle progression. Although apoptosis was not so evident with genistein alone, the combination made a drastic induction of apoptosis, accompanied by the increase of Bax/Bcl-xL expression ratio, without affecting the activities of Akt and mTOR. Taken together, these data suggest that enhancement of genistein activity by equol would be mainly mediated by augmented induction of apoptosis rather than arrest or delay of the cell cycle.

The Impacts of Genistein and Daidzein on Estrogen Conjugations in Human Breast Cancer Cells: A Targeted Metabolomics Approach

The beneficial effect of dietary soy food intake, especially for women diagnosed with breast cancer, is controversial, as in vitro data has shown that the soy isoflavones genistein and daidzein may even stimulate the proliferation of estrogen-receptor alpha positive (ERα+) breast cancer cells at low concentrations. As genistein and daidzein are known to inhibit key enzymes in the steroid metabolism pathway, and thus may influence levels of active estrogens, we investigated the impacts of genistein and daidzein on the formation of estrogen metabolites, namely 17β-estradiol (E2), 17β-estradiol-3-(β-D-glucuronide) (E2-G), 17β-estradiol-3-sulfate (E2-S) and estrone-3-sulfate (E1-S) in estrogen-dependent ERα+ MCF-7 cells. We found that both isoflavones were potent inhibitors of E1 and E2 sulfation (85–95% inhibition at 10 μM), but impeded E2 glucuronidation to a lesser extent (55–60% inhibition at 10 μM). The stronger inhibition of E1 and E2 sulfation compared with E2 glucuronidation was more evident for genistein, as indicated by significantly lower inhibition constants for genistein [K_is: E2-S (0.32 μM) < E1-S (0.76 μM) < E2-G (6.01 μM)] when compared with those for daidzein [K_is: E2-S (0.48 μM) < E1-S (1.64 μM) < E2-G (7.31 μM)]. Concomitant with the suppression of E1 and E2 conjugation, we observed a minor but statistically significant increase in E2 concentration of approximately 20%. As the content of genistein and daidzein in soy food is relatively low, an increased risk of breast cancer development and progression in women may only be observed following consumption of high-dose isoflavone supplements. Further long-term human studies monitoring free estrogens and their conjugates are therefore highly warranted to evaluate the potential side effects of high-dose genistein and daidzein, especially in patients diagnosed with ERα+ breast cancer.

The role of soybean extracts and isoflavones in hormone-dependent breast cancer: aromatase activity and biological effects

Estrogen receptor-positive (ER+) breast cancer is the most common cause of cancer death in women worldwide. Nowadays, the relationship between soya diet and breast cancer is controversial due to the unknown role of its isoflavones, genistein (G) and daidzein (D). In this work, we investigated not only the anti-tumor properties of a soybean extract (NBSE) but also whether the biotransformation of extract (BSE) by the fungus Aspergillus awamori increased its effectiveness. The BSE showed a stronger anti-aromatase activity and anti-proliferative efficacy in ER+ aromatase-overexpressing breast cancer cells. D and G were weak aromatase inhibitors, but inhibited cancer cell growth, being G the isoflavone that contributed to the BSE-induced effects. This work demonstrated that the biotransformation increased the anti-aromatase activity and the anti-tumoral efficacy of soybean extract in breast cancer cells. Moreover, it elucidated the potential use of soya in the prevention and/or treatment of ER+ breast cancer.

Dietary Natural Products for Prevention and Treatment of Breast Cancer

Breast cancer is the most common cancer among females worldwide. Several epidemiological studies suggested the inverse correlation between the intake of vegetables and fruits and the incidence of breast cancer. Substantial experimental studies indicated that many dietary natural products could affect the development and progression of breast cancer, such as soy, pomegranate, mangosteen, citrus fruits, apple, grape, mango, cruciferous vegetables, ginger, garlic, black cumin, edible macro-fungi, and cereals. Their anti-breast cancer effects involve various mechanisms of action, such as downregulating ER-α expression and activity, inhibiting proliferation, migration, metastasis and angiogenesis of breast tumor cells, inducing apoptosis and cell cycle arrest, and sensitizing breast tumor cells to radiotherapy and chemotherapy. This review summarizes the potential role of dietary natural products and their major bioactive components in prevention and treatment of breast cancer, and special attention was paid to the mechanisms of action.

MicroRNA-503 inhibits the proliferation and invasion of breast cancer cells via targeting insulin-like growth factor 1 receptor

MicroRNAs (miRs), a class of non-coding RNAs that are 18–25 nucleotides in length, serve as key regulators in the development and progression of human cancers. Previously, miR-503 has been implicated in breast cancer. However, the underlying mechanism of miR-503 in regulating the proliferation and invasion of breast cancer cells remains largely unknown. In the present study, reverse transcription-quantitative polymerase chain reaction analysis indicated that the expression of miR-503 was significantly reduced in breast cancer tissues compared with their matched adjacent normal tissues. Furthermore, miR-503 expression levels were markedly reduced in T2-T4 stage breast cancer, compared with T1 stage. Insulin-like growth factor 1 receptor (IGF-1R) was further identified as a novel target of miR-503. Overexpression of miR-503 significantly suppressed the protein expression levels of IGF-1R. Furthermore, it inhibited the proliferation and invasion of human breast cancer MCF-7 cells, as assessed by MTT and Transwell assays, respectively. However, restoration of IGF-1R expression markedly ameliorated the suppressive effects of miR-503 overexpression on MCF-7 cell proliferation and invasion, indicating that miR-503 inhibits breast cancer cell proliferation and invasion at least partially via directly targeting IGF-1R. Furthermore, the mRNA and protein expression levels of IGF-1R were demonstrated to be significantly increased in breast cancer tissues compared with their matched adjacent normal tissues. In addition, IGF-1R mRNA expression levels were reversely correlated with miR-503 expression levels in breast tumors, suggesting that the upregulation of IGF-1R may be due to downregulation of miR-503 in breast cancer. In conclusion, the present study expanded the understanding of the regulatory mechanism of miR-503 in breast cancer, and implicates the miR-503/IGF-1R axis as a potential therapeutic target for breast cancer.

Dietary Intervention by Phytochemicals and Their Role in Modulating Coding and Non-Coding Genes in Cancer

Phytochemicals are natural compounds synthesized as secondary metabolites in plants, representing an important source of molecules with a wide range of therapeutic applications. These natural agents are important regulators of key pathological processes/conditions, including cancer, as they are able to modulate the expression of coding and non-coding transcripts with an oncogenic or tumour suppressor role. These natural agents are currently exploited for the development of therapeutic strategies alone or in tandem with conventional treatments for cancer. The aim of this paper is to review the recent studies regarding the role of these natural phytochemicals in different processes related to cancer inhibition, including apoptosis activation, angiogenesis and metastasis suppression. From the large palette of phytochemicals we selected epigallocatechin gallate (EGCG), caffeic acid phenethyl ester (CAPE), genistein, morin and kaempferol, due to their increased activity in modulating multiple coding and non-coding genes, targeting the main hallmarks of cancer.

Network Pharmacological Screening of Herbal Monomers that Regulate Apoptosis-Associated Genes in Acute Pancreatitis

OBJECTIVES

In this study, we screened for differentially expressed genes in acute pancreatitis and the herbal monomers that regulate these genes.

METHODS

Gene expression profile data were downloaded from the Gene Expression Omnibus database (GSE3644). We used the Human Protein Reference Database to determine the protein-protein interaction network and CFinder software (Department of Biological Physics of Eötvös University, Budapest, Hungary) to identify several functional modules. Then, we used Database for Annotation, Visualization and Integrated Discovery software (Frederick, Md) to perform a gene ontology-biological process functional enrichment analysis. Based on a database of herbal monomers and a literature search, we constructed a gene-herbal monomer regulatory network using Cytoscape software (San Diego, Calif), and we analyzed the relationships between apoptosis, genes, and herbal monomers.

RESULTS

A total of 1745 differentially expressed genes were identified. Nine modules were identified, and the main function of module 3 was closely related to apoptosis. Within module 3, we selected 13 genes that were closely related to apoptosis for further analysis. In the gene-herbal monomer regulatory network, 18 herbal monomers that regulate multiple target genes were selected as the focus of this study.

CONCLUSIONS

These herbal monomers regulate multiple target genes to induce apoptosis and may potentially be used as new drugs for acute pancreatitis treatment in the future.

Recent development of targeted approaches for the treatment of breast cancer

Breast cancer is the most prominent cause of cancer death in women worldwide. The highlights of this review are to provide an overview of the targeted therapeutic agents, challenges with metastatic breast cancer (MBCa), mechanisms of action through Hedgehog/Gli 1 signaling pathway and future prospective. Over a decade of success, several drugs have been approved and are in the advanced stages of clinical trials that target the receptors such as estrogen receptor, growth factor receptor, receptor activator of nuclear factor kappa-B, etc. Currently, several monoclonal antibodies are also used for the treatment of breast cancer. Advances in understanding tumor biology, particularly signaling pathways such as Notch signaling pathway, Hedgehog/Gli 1 signaling pathway, and inhibitors are considered to be important for bone metastasis. These studies may provide vital information for the design and development of new strategies with respect to efficacy, reduction of the side effects, and treatment strategies.

The Anti-Cancer Effect of Polyphenols against Breast Cancer and Cancer Stem Cells: Molecular Mechanisms

The high incidence of breast cancer in developed and developing countries, and its correlation to cancer-related deaths, has prompted concerned scientists to discover novel alternatives to deal with this challenge. In this review, we will provide a brief overview of polyphenol structures and classifications, as well as on the carcinogenic process. The biology of breast cancer cells will also be discussed. The molecular mechanisms involved in the anti-cancer activities of numerous polyphenols, against a wide range of breast cancer cells, in vitro and in vivo, will be explained in detail. The interplay between autophagy and apoptosis in the anti-cancer activity of polyphenols will also be highlighted. In addition, the potential of polyphenols to target cancer stem cells (CSCs) via various mechanisms will be explained. Recently, the use of natural products as chemotherapeutics and chemopreventive drugs to overcome the side effects and resistance that arise from using chemical-based agents has garnered the attention of the scientific community. Polyphenol research is considered a promising field in the treatment and prevention of breast cancer.

The Impact of Soy Isoflavones on MCF-7 and MDA-MB-231 Breast Cancer Cells Using a Global Metabolomic Approach

Despite substantial research, the understanding of the chemopreventive mechanisms of soy isoflavones remains challenging. Promising tools, such as metabolomics, can provide now a deeper insight into their biochemical mechanisms. The purpose of this study was to offer a comprehensive assessment of the metabolic alterations induced by genistein, daidzein and a soy seed extract on estrogen responsive (MCF-7) and estrogen non-responsive breast cancer cells (MDA-MB-231), using a global metabolomic approach. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed that all test compounds induced a biphasic effect on MCF-7 cells and only a dose-dependent inhibitory effect on MDA-MB-231 cells. Proton nuclear magnetic resonance (¹H-NMR) profiling of extracellular metabolites and gas chromatography-mass spectrometry (GC-MS) profiling of intracellular metabolites confirmed that all test compounds shared similar metabolic mechanisms. Exposing MCF-7 cells to stimulatory concentrations of isoflavones led to increased intracellular levels of 6-phosphogluconate and ribose 5-phosphate, suggesting a possible upregulation of the pentose phosphate pathway. After exposure to inhibitory doses of isoflavones, a significant decrease in glucose uptake was observed, especially for MCF-7 cells. In MDA-MB-231 cells, the glutamine uptake was significantly restricted, leading to alterations in protein biosynthesis. Understanding the metabolomic alterations of isoflavones represents a step forward in considering soy and soy derivates as functional foods in breast cancer chemoprevention.

Evidence for genistein as a mitochondriotropic molecule

Genistein (4',5,7-trihydroxyisoflavone; C15H10O5), an isoflavone, has been investigated as an anti-cancer agent due to its ability to trigger cell death (both intrinsic and extrinsic apoptotic pathways) in different cancer cells in vitro and in vivo. Furthermore, genistein has been viewed as a mitochondriotropic molecule due to the direct effects this isoflavone induces in mitochondria, such as modulation of enzymatic activity of components of the oxidative phosphorylation system. Apoptosis triggering may also be mediated by genistein through activation of the mitochondria-dependent pathway by a mechanism associated with mitochondrial dysfunction (i.e., disruption of the mitochondrial membrane potential - MMP, release of cytochrome c, activation of the apoptosome, among others). Efforts have been made in order to elucidate how genistein coordinate these biochemical phenomena. Nonetheless, some areas of the mitochondria-associated research (mitochondrial biogenesis, redox biology of mitochondria, and mitochondria-associated bioenergetic parameters) need to be explored regarding the role of genistein as a mitochondria-targeted agent. This is a pharmacologically relevant issue due to the possibility of using genistein as a mitochondria-targeted drug in cases of cancer, neurodegeneration, cardiovascular, and endocrine disease, for example. The present review aims to describe, compare, and discuss relevant data about the effects of genistein upon mitochondria.

Genistein induces adipogenic differentiation in human bone marrow mesenchymal stem cells and suppresses their osteogenic potential by upregulating PPARγ

Genistein is a soy isoflavone that exists in the form of an aglycone. It is the primary active component in soy isoflavone and has a number of biological activities (anti-inflammatory and anti-oxidative). However, the specific effect of genistein on human bone marrow mesenchymal stem cells (BMSCs) remains unclear. In the present study, the mechanism underlying the effect of genistein on the suppression of BMSC adipogenic differentiation and the enhancement of osteogenic potential was investigated using an MTT assay. It was observed that genistein significantly increased BMSC cell proliferation in a time- and dose-dependent manner (P<0.01). In addition, reverse transcription-quantitative polymerase chain reaction revealed that genistein significantly inhibited the expression of runt-related transcription factor 2 (Runx2), type I collagen (Col I) and osteocalcin (OC; P<0.01). Furthermore, 20 µm genistein significantly inhibited the activity of alkaline phosphatase (ALP) and increased the activity of triglycerides (TGs) increased (P<0.01) as determined by an enzyme-linked immunosorbent assay. Finally, western blotting revealed that BMSC pretreatment with 20 µm genistein significantly increased peroxisome proliferator-activated receptor γ (PPARγ) protein expression (P<0.01). This suggests that the downregulation of PPARγ may significantly reduce the effect of genistein on cell proliferation, suppress the expression of Runx2, Col I and OC mRNA, and reduce ALP and promote TG activity in BMSCs. Thus, the results of the present study conclude that genistein induces adipogenic differentiation in human BMSCs and suppresses their osteogenic potential by upregulating the expression of PPARγ. In conclusion, genistein may be a promising candidate drug for treatment against osteogenesis.

Soy Isoflavones and Breast Cancer Cell Lines: Molecular Mechanisms and Future Perspectives

The potential benefit of soy isoflavones in breast cancer chemoprevention, as suggested by epidemiological studies, has aroused the interest of numerous scientists for over twenty years. Although intensive work has been done in this field, the preclinical results continue to be controversial and the molecular mechanisms are far from being fully understood. The antiproliferative effect of soy isoflavones has been commonly linked to the estrogen receptor interaction, but there is growing evidence that other pathways are influenced as well. Among these, the regulation of apoptosis, cell proliferation and survival, inhibition of angiogenesis and metastasis or antioxidant properties have been recently explored using various isoflavone doses and various breast cancer cells. In this review, we offer a comprehensive perspective on the molecular mechanisms of isoflavones observed in in vitro studies, emphasizing each time the dose-effect relationship and estrogen receptor status of the cells. Furthermore, we present future research directions in this field which could provide a better understanding of the inner molecular mechanisms of soy isoflavones in breast cancer.

Chemoprevention of Breast Cancer by Dietary Polyphenols

The review will discuss in detail the effects of polyphenols on breast cancer, including both the advantages and disadvantages of the applications of these natural compounds. First, we focus on the characterization of the main classes of polyphenols and then on in vitro and in vivo experiments carried out in breast cancer models. Since the therapeutic effects of the administration of a single type of polyphenol might be limited because of the reduced bioavailability of these drugs, investigations on combination of several polyphenols or polyphenols with conventional therapy will also be discussed. In addition, we present recent data focusing on clinical trials with polyphenols and new approaches with nanoparticles in breast cancer. Besides the clinical and translational findings this review systematically summarizes our current knowledge about the molecular mechanisms of anti-cancer effects of polyphenols, which are related to apoptosis, cell cycle regulation, plasma membrane receptors, signaling pathways and epigenetic mechanisms. At the same time the effects of polyphenols on primary tumor, metastasis and angiogenesis in breast cancer are discussed. The increasing enthusiasm regarding the combination of polyphenols and conventional therapy in breast cancer might lead to additional efforts to motivate further research in this field.

Phytoestrogen genistein inhibits EGFR/PI3K/NF-kB activation and induces apoptosis in human endometrial hyperplasial cells

Endometrial hyperplasia is an estrogen-dependent disease and is the most frequent precursor of endometrial cancer, diagnosed in pre- and peri-menopausal women.