Membrane fluidity, invasiveness and dynamic phenotype of metastatic prostate cancer cells after treatment with soy isoflavones

The Pros and Cons of Estrogens in Prostate Cancer: An Update with a Focus on Phytoestrogens

The role of estrogens in prostate cancer (PCa) is shrouded in mystery, with its actions going from angelic to devilish. The findings by Huggins and Hodges establishing PCa as a hormone-sensitive cancer have provided the basis for using estrogens in therapy. However, despite the clinical efficacy in suppressing tumor growth and the panoply of experimental evidence describing its anticarcinogenic effects, estrogens were abolished from PCa treatment because of the adverse secondary effects. Notwithstanding, research work over the years has continued investigating the effects of estrogens, reporting their pros and cons in prostate carcinogenesis. In contrast with the beneficial therapeutic effects, many reports have implicated estrogens in the disruption of prostate cell fate and tissue homeostasis. On the other hand, epidemiological data demonstrating the lower incidence of PCa in Eastern countries associated with a higher consumption of phytoestrogens support the beneficial role of estrogens in counteracting cancer development. Many studies have investigated the effects of phytoestrogens and the underlying mechanisms of action, which may contribute to developing safe estrogen-based anti-PCa therapies. This review compiles the existing data on the anti- and protumorigenic actions of estrogens and summarizes the anticancer effects of several phytoestrogens, highlighting their promising features in PCa treatment.

Bimodal effects on lipid droplets induced in cancer and non-cancer cells by chemotherapy drugs as revealed with a green-emitting BODIPY fluorescent probe

Lipid droplets (LDs) are cytoplasmic lipid-rich organelles with important roles in lipid storage and metabolism, cell signaling and membrane biosynthesis. Additionally, multiple diseases, such as obesity, fatty liver, cardiovascular diseases and cancer, are related to the metabolic disorders of LDs. In various cancer cells, LD accumulation is associated with resistance to cell death, reduced effectiveness of chemotherapeutic drugs, and increased proliferation and aggressiveness. In this work, we present a new viscosity-sensitive, green-emitting BODIPY probe capable of distinguishing between ordered and disordered lipid phases and selectively internalising into LDs of live cells. Through the use of fluorescence lifetime imaging microscopy (FLIM), we demonstrate that LDs in live cancer (A549) and non-cancer (HEK 293T) cells have vastly different microviscosities. Additionally, we quantify the microviscosity changes in LDs under the influence of DNA-damaging chemotherapy drugs doxorubicin and etoposide. Finally, we show that doxorubicin and etoposide have different effects on the microviscosities of LDs in chemotherapy-resistant A549 cancer cells.

Differential Effects of Soy Isoflavones on the Biophysical Properties of Model Membranes

The effects that the main soy isoflavones, genistein and daidzein, have upon the biophysical properties of a model lipid bilayer composed of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) or DOPC with cholesterol (4 to 1 mol ratio) have been investigated by transbilayer water permeability, differential scanning calorimetry, and confocal Raman microspectroscopy. Genistein is found to increase water permeability, decrease phase transition temperature, reduce enthalpy of transition, and induce packing disorder in the DOPC membrane with an increasing concentration. On the contrary, daidzein decreases water permeability and shows negligible impact on thermodynamic parameters and packing disorder at comparable concentrations. For a cholesterol-containing DOPC bilayer, both genistein and daidzein exhibit an overall less pronounced effect on transbilayer water permeability. Their respective differential abilities to modify the physical and structural properties of biomembranes with varying lipid compositions signify a complex and sensitive nature to isoflavone interactions, which depends on the initial state of bilayer packing and the differences in the molecular structures of these soy isoflavones, and provide insights in understanding the interactions of these molecules with cellular membranes.

Investigation of apoptotic and antiproliferative effects of Turkish natural tetraploids Trifolium pratense L. extract on C6 glioblastoma cells via light and electron microscopy

Glioblastoma (GBM) is the most common type of primary brain tumors in adults, characterized by its ability to proliferate rapidly and its tendency to aggressively and strongly invaded the surrounding brain tissue. The standard treatment approach of GBM is surgical resection followed by simultaneous chemotherapy and radiation. However, a significant number of GBM cases develop resistance to currently used chemotherapeutic drugs. Therefore, there is a need for the development of new chemotherapeutic agents. Trifoliumpratense L. is an endemic plant containing various isoflavones such as biochanin A, genistein, daidzein, and formononetin in high concentrations, and it has been shown in various studies that these molecules can function as anticancer agents. The present study was designed to determine the effect of the possible anticarcinogenic effects of the Trifolium pratense L. which grown in our country and to obtain new treatment approaches alternative to the classical treatment protocols applied in the treatment of GBM. C6 glioblastoma cells were cultured with Trifolium pratense L. Cell proliferation, apoptotic cell morphology, and cell structure were evaluated with CCK8, Annexin V, cytochrome c, CD117, and Betatubulin labeling, respectively. And also, investigated effects of this Turkish tetraploid on GBM by TEM. Decreased cell proliferation and increased number of apoptotic cells were observed depending on the increasing doses of Trifolium pratense L. In addition, intense morphological changes were detected depending on increasing doses. In this context, we believe that the plant Trifolium pratense L., may be a new alternative and adjuvant agent for the treatment of GBM.

Nanoparticles loaded with pharmacologically active plant-derived natural products: Biomedical applications and toxicity

Pharmacologically active natural products have played a significant role in the history of drug development. They have acted as sources of therapeutic drugs for various diseases such as cancer and infectious diseases. However, most natural products suffer from poor water solubility and low bioavailability, limiting their clinical applications. The rapid development of nanotechnology has opened up new directions for applying natural products and numerous studies have explored the biomedical applications of nanomaterials loaded with natural products. This review covers the recent research on applying plant-derived natural products (PDNPs) nanomaterials, including nanomedicines loaded with flavonoids, non-flavonoid polyphenols, alkaloids, and quinones, especially their use in treating various diseases. Furthermore, some drugs derived from natural products can be toxic to the body, so the toxicity of them is discussed. This comprehensive review includes fundamental discoveries and exploratory advances in natural product-loaded nanomaterials that may be helpful for future clinical development.

Chemopreventive Potential of Dietary Nanonutraceuticals for Prostate Cancer: An Extensive Review

There are more than two hundred fifty different types of cancers, that are diagnosed around the world. Prostate cancer is one of the suspicious type of cancer spreading very fast around the world, it is reported that in 2018, 29430 patients died of prostate cancer in the United State of America (USA), and hence it is expected that one out of nine men diagnosed with this severe disease during their lives. Medical science has identified cancer at several stages and indicated genes mutations involved in the cancer cell progressions. Genetic implications have been studied extensively in cancer cell growth. So most efficacious drug for prostate cancer is highly required just like other severe diseases for men. So nutraceutical companies are playing major role to manage cancer disease by the recommendation of best natural products around the world, most of these natural products are isolated from plant and mushrooms because they contain several chemoprotective agents, which could reduce the chances of development of cancer and protect the cells for further progression. Some nutraceutical supplements might activate the cytotoxic chemotherapeutic effects by the mechanism of cell cycle arrest, cell differentiation procedures and changes in the redox states, but in other, it also elevate the levels of effectiveness of chemotherapeutic mechanism and in results, cancer cell becomes less reactive to chemotherapy. In this review, we have highlighted the prostate cancer and importance of nutraceuticals for the control and management of prostate cancer, and the significance of nutraceuticals to cancer patients during chemotherapy.

Development of genistein-loaded gold nanoparticles and their antitumor potential against prostate cancer cell lines

Soy isoflavone genistein (Gen) exerts beneficial effects against prostate cancer cells in vitro and in vivo. However, its use as a chemoprevention/therapeutic agent is largely limited due to its low bioavailability. In this study we synthesized two variants of a new delivery system, genistein-gold nanoparticles conjugates Gen@AuNPs1 and Gen@AuNPs2, by an environmentally friendly method, using a dual role of Gen to reduce Au³⁺ and stabilize the formed AuNPs, with no additional component. The formation of Gen@AuNPs was confirmed via UV-Vis spectroscopy, FTIR, and Raman spectra measurements. The spherical shape and uniform size of Gen@AuNPs1 and Gen@AuNPs2 (10 ± 2 and 23 ± 3 nm, respectively), were determined by transmission electron microscopy. The nano-conjugates also varied in hydrodynamic diameter (65.0 ± 1.7 and 153.0 ± 2.2 nm) but had similar negative zeta potential (-35.0 ± 2.5 and -37.0 ± 1.6 mV), as measured by dynamic light scattering. The Gen loading was estimated to be 46 and 48%, for Gen@AuNPs1 and Gen@AuNPs2, respectively. The antiproliferative activities of GenAuNPs were confirmed by MTT test in vitro on three malignant prostate carcinoma cell lines (PC3, DU 145, and LNCaP), while selectivity toward malignant phenotype was confirmed using non-cancerous MRC-5 cells. Flow cytometric analysis showed that the inhibition on cell proliferation of more potent Gen@AuNPs1 nano-conjugate is comparable with the effects of free Gen. In conclusion, the obtained results, including physicochemical characterization of newly synthesized AuNPs loaded with Gen, cytotoxicity, and IC₅₀ assessments, indicate their stability and bioactivity as an antioxidant and anti-prostate cancer agent, with low toxicity against human primary cells.

C-Glucosylation as a tool for the prevention of PAINS-induced membrane dipole potential alterations

The concept of Pan-Assay Interference Compounds (PAINS) is regarded as a threat to the recognition of the broad bioactivity of natural products. Based on the established relationship between altered membrane dipole potential and transmembrane protein conformation and function, we investigate here polyphenols' ability to induce changes in cell membrane dipole potential. Ultimately, we are interested in finding a tool to prevent polyphenol PAINS-type behavior and produce compounds less prone to untargeted and promiscuous interactions with the cell membrane. Di-8-ANEPPS fluorescence ratiometric measurements suggest that planar lipophilic polyphenols-phloretin, genistein and resveratrol-act by decreasing membrane dipole potential, especially in cholesterol-rich domains such as lipid rafts, which play a role in important cellular processes. These results provide a mechanism for their labelling as PAINS through their ability to disrupt cell membrane homeostasis. Aiming to explore the role of C-glucosylation in PAINS membrane-interfering behavior, we disclose herein the first synthesis of 4-glucosylresveratrol, starting from 5-hydroxymethylbenzene-1,3-diol, via C-glucosylation, oxidation and Horner-Wadsworth-Emmons olefination, and resynthesize phloretin and genistein C-glucosides. We show that C-glucosylation generates compounds which are no longer able to modify membrane dipole potential. Therefore, it can be devised as a strategy to generate bioactive natural product derivatives that no longer act as membrane dipole potential modifiers. Our results offer a new technology towards rescuing bioactive polyphenols from their PAINS danger label through C-C ligation of sugars.

Artichoke extracts in cancer therapy: do the extraction conditions affect the anticancer activity?

Background

Artichoke is an edible plant that is grown in the Mediterranean region and is known for its antimicrobial, antifungal, antibacterial, antioxidant and anticancer activities. Different artichoke extraction methods can impressively affect the nature as well as the yield of the extracted components.

Main body

The different methods of artichoke extraction and the influence of the extraction conditions on the extraction efficiency are summarized herein. In addition, cancer causalities and hallmarks together with the molecular mechanisms of artichoke active molecules in cancer treatment are also discussed. Moreover, a short background is given on the common types of cancer that can be treated with artichoke extracts as well as their pathogenesis. A brief discussion of the previous works devoted to the application of artichoke extracts in the treatment of these cancers is also given.

Conclusion

This review article covers the extraction methods, composition, utilization and applications of artichoke extracts in the treatment of different cancers.

Lipid rafts as potential mechanistic targets underlying the pleiotropic actions of polyphenols

Polyphenols have attracted a lot of global attention due to their diverse biological actions against cancer, obesity, and cardiovascular diseases. Although extensive research has been carried out to elucidate the mechanisms of pleiotropic actions of polyphenols, this remains unclear. Lipid rafts are distinct nanodomains enriched in cholesterol and sphingolipids, present in the inner and outer leaflets of cell membranes, forming functional platforms for the regulation of cellular processes and diseases. Recent studies focusing on the interaction between polyphenols and cellular lipid rafts shed new light on the pleiotropic actions of polyphenols. Polyphenols are postulated to interact with lipid rafts in two ways: first, they interfere with the structural integrity of lipid rafts, by disrupting their structure and clustering of the ordered domains; second, they modulate the downstream signaling pathways mediated by lipid rafts, by binding to receptor proteins associated with lipid rafts, such as the 67 kDa laminin receptor (67LR), epidermal growth factor receptor (EGFR), and others. This study aims to elaborate the mechanism of interaction between polyphenols and lipid rafts, and describe pleiotropic preventive effects of polyphenols.

Evaluation of Viburnum opulus L. Fruit Phenolics Cytoprotective Potential on Insulinoma MIN6 Cells Relevant for Diabetes Mellitus and Obesity

In this study, the influence of guelder rose (Viburnum opulus) fruit fresh juice (FJ) and a phenolic-rich fraction (PRF) isolated from juice on mice insulinoma MIN6 cells activities was investigated. Extracts were able to decrease intracellular oxidative stress at the highest non-cytotoxic concentrations. They induced glucagon-like peptide-1 (GLP-1) secretion in the presence of an elevated glucose concentration, and they inhibited in vitro activity of the dipeptidyl peptidase-4 (DPP4) enzyme. Nonetheless, inhibition of glucose-stimulated insulin secretion was detected, which was accompanied by a decrease of cellular membrane fluidity and hyperpolarization effect. In addition, the increase of free fatty acid uptake and accumulation of lipid droplets in MIN6 cells were observed. Elevated extract concentrations induced cell apoptosis through the intrinsic mitochondrial pathway with activation of initiatory caspase-9 and downstream caspases-3/7. The fluorescence-quenching studies indicated that PRF extract has binding affinity to human serum albumin, which is one of the factors determining drug bioavailability. Taken together, despite the cytoprotective activity against generated intracellular oxidative stress, V. opulus revealed potential toxic effects as well as decreased insulin secretion from MIN6 cells. These findings are relevant in understanding V. opulus limitations in developing diet supplements designed for the prevention and treatment of postprandial glucose elevation.

The Effects of Trifolium pratense L. Sprouts' Phenolic Compounds on Cell Growth and Migration of MDA-MB-231, MCF-7 and HUVEC Cells

Uncontrolled growth and migration and invasion abilities are common for cancer cells in malignant tumors with low therapeutic effectiveness and high mortality and morbidity. Estrogen receptor β (ERβ), as a member of the nuclear receptor superfamily, shows potent tumor suppressive activities in many cancers. Phytoestrogens’ structural resemblance to 17 β-estradiol allows their binding to ERβ isoform predominantly, and therefore, expression of genes connected with elevated proliferation, motility and invasiveness of cancer cells may be downregulated. Among polyphenolic compounds with phytoestrogenic activity, there are isoflavones from Trifolium pratense L. (red clover) sprouts, containing high amounts of formononetin and biochanin A and their glycosides. To determine the source of the most biologically active isoflavones, we obtained four extracts from sprouts before and after their lactic fermentation and/or β-glucosidase treatment. Our previous results of ITC (isothermal titration calorimetry) modelling and a docking simulation showed clover isoflavones’ affinity to ERβ binding, which may downregulate cancer cell proliferation and migration. Thus, the biological activity of T. pratense sprouts’ extracts was checked under in vitro conditions against highly invasive human breast cancer cell line MDA-MB-231 and non-invasive human breast cancer cell line MCF-7 cells. To compare extracts’ activities acquired for cancer cells with those activities against normal cells, as a third model we choose human umbilical vein endothelial cells (HUVEC), which, due to their migration abilities, are involved in blood vessel formation. Extracts obtained from fermented sprouts at IC₀ dosages were able to inhibit migration of breast cancer cells through their influence on intracellular ROS generation; membrane stiffening; adhesion; regulation of MMP-9, N-cadherin and E-cadherin at transcriptional level; or VEGF secretion. Simultaneously, isolated phenolics revealed no toxicity against normal HUVEC cells. In the manuscript, we proposed a preliminary mechanism accounting for the in vitro activity of Trifolium pratense L. isoflavones. In this manner, T. pratense sprouts, especially after their lactic fermentation, can be considered a potent source of biological active phytoestrogens and a dietary supplement with anti-cancer and anti-invasion properties.

The Cytoprotective Role of Antioxidants in Mammalian Cells Under Rapidly Varying UV Conditions During Stratospheric Balloon Campaign

The current age of dynamic development of the space industry brings the mankind closer to routine manned space flights and space tourism. This progress leads to a demand for intensive astrobiological research aimed at improving strategies of the pharmacological protection of the human cells against extreme conditions. Although routine research in space remains out of our reach, it is worth noticing that the unique severe environment of the Earth's stratosphere has been found to mimic subcosmic conditions, giving rise to the opportunity to use the stratospheric surface as a research model for the astrobiological studies. Our study included launching into the stratosphere a balloon containing mammalian normal and cancer cells treated with various compounds to examine whether these substances are capable of protecting the cells against stress caused by rapidly varying temperature, pressure, and radiation, especially UV. Owing to oxidative stress caused by irradiation and temperature shock, we used natural compounds which display antioxidant properties, namely, catechin isolated from green tea, honokiol derived from magnolia, curcumin from turmeric, and cinnamon extract. "After-flight" laboratory tests have shown the most active antioxidants as potential agents which can minimize harmful impact of extreme conditions on human cells.

Common chemotherapeutic agents modulate fatty acid distribution in human hepatocellular carcinoma and colorectal cancer cells

Introduction: Cancer cells are critically correlated with lipid molecules, particularly fatty acids, as structural blocks for membrane building, energy sources, and related signaling molecules. Therefore, cancer progression is in direct correlation with fatty acid metabolism. The aim of this study was to investigate the potential effects of common chemotherapeutic agents on the lipid metabolism of hepatocellular carcinoma (HCC) and colorectal cancer (CRC) cells, with a focus on alterations in cellular fatty acid contents.

Methods: Human HepG2 and SW480 cell lines as HCC and CRC cells were respectively cultured in RPMI-1640 medium supplemented with non-toxic doses of 5-fluorouracil and doxorubicin for 72 hours. Oil Red O dye was used to estimate intracellular lipid vacuole intensity. Fatty acid analysis of isolated membrane phospholipids and cytoplasmic triglycerides (TG) was performed by gas-liquid chromatography (GLC) technique.

Results: Oil red O staining represented significantly higher lipid accumulation and density in cancer cells after exposure to the chemotherapeutic agents as compared to non-treated control cells. Doxorubicin and 5-fluorouracil treatment promoted the channeling of saturated fatty acids (SFAs) from phospholipids to triglyceride pool in both HepG2 (+5.91% and +8.50%, P < 0.05, respectively) and SW480 (+37.41% and +5.73%, P < 0.05, respectively) cell lines. However, total polyunsaturated fatty acid content was inversely shifted from TG to phospholipid fraction after doxorubicin and 5-fluorouracil incubation of HepG2 (+58.89% and +29.13%, P < 0.05, respectively) and SW480 (+19.20% and +14.65%, P < 0.05, respectively) cells.

Conclusion: Our data showed that common chemotherapeutic agents of HCC and CRC can induce significant changes in cellular lipid accumulation and distribution of fatty acids through producing highly saturated and unsaturated lipid droplets and membrane lipids, respectively. These metabolic side effects may be associated with gastrointestinal cancers treatment failure.

Membrane steroid receptor-mediated action of soy isoflavones: tip of the iceberg

Soy isoflavone's (genistein and daidzein in particular) biological significance has been thoroughly studied for decades, so we started from the premise that refreshed investigation approach in this field should consider identification of their new molecular targets. In addition to recently described epigenetic aspects of polyphenole action, the cell membrane constituents-mediated effects of soy isoflavones are worthy of special attention. Accordingly, the expanding concept of membrane steroid receptors and rapid signaling from the cell surface may include the prominent role of these steroid-like compounds. It was observed that daidzein strongly interacts with membrane estrogen receptors in adrenal medullary cells. At low doses, daidzein was found to stimulate catecholamine synthesis through extracellular signal-regulated kinase 1/2 or protein kinase A pathways, but at high doses, it inhibited catecholamine synthesis and secretion induced by acetylcholine. Keeping in mind that catecholamine excess can contribute to the cardiovascular pathologies and that catecholamine lack may lead to depression, daidzein application promises to have a wide range of therapeutic effects. On the other hand, it was shown in vitro that genistein inhibits LNCaP prostate cancer cells invasiveness by decreasing the membrane fluidity along with immobilization of the androgen receptor containing membrane lipid rafts, with down regulation of the androgen receptors and Akt signaling. These data are promising in development of the molecular pharmacotherapy pertinent to balanced soy isoflavone treatment of cardiovascular, psychiatric, and steroid-related malignant diseases.

Soy isoflavones and cellular mechanics

Soy isoflavones are diphenolic compounds that are frequently used for alternative treatment of ageing symptoms in both genders. They operate at principally two hierarchical levels of functional organization - cellular and molecular, while these 'types' of action appear to have indefinite borders. Soy isoflavone action at the cellular level involves inter alia the effects on cell mechanics. This epigenetic and modular determinant of cell function and fate is defined by: the anchorage to extracellular matrix (ECM) and neighboring cells, cytoskeleton organization, membrane tension and vesicle trafficking. Soy isoflavones have been reported to: (i) generally fashion an inert cell phenotype in some cancers and enhance the cell anchorage in connective tissues, via the effects on ECM proteins, focal adhesion kinases-mediated events and matrix metalloproteinases inhibition; (ii) affect cytoskeleton integrity, the effects being related to Ca(2+) ions fluxes and involving cell retraction or differentiation/proliferation-related variations in mechanical status; (iii) increase, remain "silent" or decrease membrane tension/fluidity, which depends on polarity and a number and arrangement of functional groups in applied isoflavone; (iv) provoke inhibitory effects on vesicle trafficking and exo-/endocytosis, which are usually followed by changed cell morphology. Here we present and discuss the abundance of effects arising from cells' "encounter" with soy isoflavones, focusing on different morphofunctional definers of cell mechanics.

Flavonoid-membrane interactions: involvement of flavonoid-metal complexes in raft signaling

Flavonoids are polyphenolic compounds produced by plants and delivered to the human body through food. Although the epidemiological analyses of large human populations did not reveal a simple correlation between flavonoid consumption and health, laboratory investigations and clinical trials clearly demonstrate the effectiveness of flavonoids in the prevention of cardiovascular, carcinogenic, neurodegenerative and immune diseases, as well as other diseases. At present, the abilities of flavonoids in the regulation of cell metabolism, gene expression, and protection against oxidative stress are well-known, although certain biophysical aspects of their functioning are not yet clear. Most flavonoids are poorly soluble in water and, similar to lipophilic compounds, have a tendency to accumulate in biological membranes, particularly in lipid rafts, where they can interact with different receptors and signal transducers and influence their functioning through modulation of the lipid-phase behavior. In this study, we discuss the enhancement in the lipophilicity and antioxidative activity of flavonoids after their complexation with transient metal cations. We hypothesize that flavonoid-metal complexes are involved in the formation of molecular assemblies due to the facilitation of membrane adhesion and fusion, protein-protein and protein-membrane binding, and other processes responsible for the regulation of cell metabolism and protection against environmental hazards.

Perspectives on the role of isoflavones in prostate cancer

Isoflavones have been investigated in detail for their role in the prevention and therapy of prostate cancer. This is primarily because of the overwhelming data connecting high dietary isoflavone intake with reduced risk of developing prostate cancer. A number of investigations have evaluated the mechanism(s) of anticancer action of isoflavones such as genistein, daidzein, biochanin A, equol, etc., in various prostate cancer models, both in vitro and in vivo. Genistein quickly jumped to the forefront of isoflavone cancer research, but the initial enthusiasm was followed by reports on its contradictory prometastatic and tumor-promoting effects. Use of soy isoflavone mixture has been advocated as an alternative, wherein daidzein can negate harmful effects of genistein. Recent research indicates a novel role of genistein and other isoflavones in the potentiation of radiation therapy, epigenetic regulation of key tumor suppressors and oncogenes, and the modulation of miRNAs, epithelial-to-mesenchymal transition, and cancer stem cells, which has renewed the interest of cancer researchers in this class of anticancer compounds. This comprehensive review article summarizes our current understanding of the role of isoflavones in prostate cancer research.