Synergistic anticancer effects of curcumin and resveratrol in Hepa1-6 hepatocellular carcinoma cells

Exploring the therapeutic mechanisms of resveratrol for treating arecoline-induced malignant transformation in oral epithelial cells: insights into hub targets

BACKGROUND

Betel nut chewing is a significant risk factor for oral cancer due to arecoline, its primary active component. Resveratrol, a non-flavonoid polyphenol, possesses anti-cancer properties. It has been shown to inhibit arecoline-induced oral malignant cells in preliminary experiments but the underlying mechanism remains unclear. This research therefore aimed to explore the potential therapeutic targets of resveratrol in treating arecoline-induced oral cancer.

METHODS

Data mining identified common targets and hub targets of resveratrol in arecoline-induced oral cancer. Gene set variation analysis (GSVA) was used to score and validate the expression and clinical significance of these hub targets in head and neck cancer (HNC) tissues. Molecular docking analysis was conducted on the hub targets. The effect of resveratrol intervention on hub targets was verified by experiments.

RESULTS

Sixty-one common targets and 15 hub targets were identified. Hub targets were highly expressed in HNC and were associated with unfavorable prognoses. They played a role in HNC metastasis, epithelial-mesenchymal transition, and invasion. Their expression also affected immune cell infiltration and correlated negatively with sensitivity to chemotherapeutic agents such as bleomycin and docetaxel. Experiments demonstrated that resveratrol down-regulated the expression of the hub targets, inhibited their proliferation and invasion, and induced apoptosis.

CONCLUSION

Resveratrol inhibits the arecoline-induced malignant phenotype of oral epithelial cells by regulating the expression of some target genes, suggesting that resveratrol may be used not only as an adjuvant treatment for oral cancer, but also as an adjuvant for oral cancer prevention due to its low toxicity and high efficacy. © 2024 Society of Chemical Industry.

Application of natural products in regulating ferroptosis in human diseases

BACKGROUND

Ferroptosis is a type of cell death caused by excessive iron-induced peroxidation. It has been found to be involved in a variety of diseases, and natural products can be used to target ferroptosis in treatments. Natural products are biologically active compounds extracted or synthesized from nature. It is an important resource for the discovery of skeletons with a high degree of structural diversity and a wide range of bioactivities, which can be developed directly or used as a starting point for the optimization of new drugs.

PURPOSE

In this review, we aim to discuss the interactions between natural products and ferroptosis in the treatment of human diseases.

METHODS

Literature was searched in Pubmed, Science Direct, and Web of Science databases for the 11-year period from 2012 to 2023 using the search terms "natural products", "ferroptosis", "human disease", "neurodegenerative disease", "cardiovascular disease", and "cancer".

RESULTS

In this research, the roles of natural products and ferroptosis were investigated. We suggest that natural products, such as terpenoids, flavonoids, polyphenols, alkaloids, and saponins, can be used in therapeutic applications for human diseases, as well as in ferroptosis. Additionally, the main mechanisms of ferroptosis were summarized and discussed. Furthermore, we propose that natural products can be utilized to enhance the sensitivity of cancer cells to ferroptosis, thus helping to overcome drug resistance and inhibit metastasis. Moreover, natural products have the potential to modulate the expression levels of ferroptosis-related factors. Finally, the future directions of this field were highlighted.

CONCLUSION

The potential of natural products which focus on ferroptosis to treat human illnesses, particularly cancer, is very encouraging for human wellbeing.

Exploration of the Molecular Mechanism of Curcuma aromatica Salisb's Anticolorectal Cancer Activity via the Integrative Approach of Network Pharmacology and Experimental Validation

Curcuma aromatica Salisb (Cur), a well-known herbal medicine, has a wide spectrum of anti-inflammatory, anticarcinogenic, and antioxidant activities. However, the roles of its active compounds and potential mechanisms in colorectal cancer remain unknown. This research utilized network pharmacology and experimental validation to explore the possible mechanisms by which Cur protects against colorectal cancer. The active compounds of Cur and related genes for colorectal cancer were obtained from public databases. The DrugBank database was used to search for anticolorectal cancer drugs licensed through the FDA and their targets, and a "drug-component-target" relationship network was created using the Cytoscape program. The String database produced the PPI network. The ability of these active ingredients to bind to core targets was confirmed by molecular docking using AutoDock Vina. Cell and animal experiments were then carried out. A total of 274 targets were obtained from Cur, 49 of which were potential therapeutic targets. Four key targets, PTGS2, AKT1, TP53, and estrogen receptor 1 (ESR1), were screened via the PPI network and the FDA drug-target network. Molecular docking results revealed that Cur had strong binding abilities to these targets. In vivo and in vitro experiments demonstrated that Cur suppressed the development of colorectal cancer by regulating its targets (PTGS2, AKT1, TP53, and ESR1), which play crucial roles in promoting apoptosis and suppressing cell proliferation, migration, and invasion. Collectively, Cur protects against colorectal cancer by regulating the AKT1/PTGS2/ESR1 and P53 pathways, which lays the groundwork for further research and clinical applications of Cur in colorectal cancer therapy.

Antioxidant curcumin induces oxidative stress to kill tumor cells (Review)

Curcumin is a plant polyphenol in turmeric root and a potent antioxidant. It binds to antioxidant response elements for gene regulation by nuclear factor erythroid 2-related factor 2, thereby suppressing reactive oxygen species (ROS) and exerting anti-inflammatory, anti-infective and other pharmacological effects. Of note, curcumin induces oxidative stress in tumors. It binds to several enzymes in tumors, such as carbonyl reductases, glutathione S-transferase P1 and nicotinamide adenine dinucleotide phosphate to induce mitochondrial damage, increase ROS production and ultimately induce tumor cell death. However, the instability and poor pharmacokinetic profile of curcumin in vivo limit its clinical application. Therefore, the effects of curcumin in vivo may be enhanced through its combination with drugs, derivative development and nanocarriers. In the present review, the mechanisms of curcumin that induce tumor cell death through oxidative stress are discussed. In addition, the methods used to enhance the antitumor activity of curcumin are described. Finally, the existing knowledge on the functions of curcumin in tumors, particularly in terms of oxidative stress, are summarized to facilitate future curcumin research.

The Combination of Bioavailable Concentrations of Curcumin and Resveratrol Shapes Immune Responses While Retaining the Ability to Reduce Cancer Cell Survival

The polyphenols Curcumin (CUR) and Resveratrol (RES) are widely described for their antitumoral effects. However, their low bioavailability is a drawback for their use in therapy. The aim of this study was to explore whether CUR and RES, used at a bioavailable concentration, could modulate immune responses while retaining antitumor activity and to determine whether CUR and RES effects on the immune responses of peripheral blood mononuclear cells (PBMCs) and tumor growth inhibition could be improved by their combination. We demonstrate that the low-dose combination of CUR and RES reduced the survival of cancer cell lines but had no effect on the viability of PBMCs. Although following CUR + RES treatment T lymphocytes showed an enhanced activated state, RES counteracted the increased IFN-γ expression induced by CUR in T cells and the polyphenol combination increased IL-10 production by T regulatory cells. On the other hand, the combined treatment enhanced NK cell activity through the up- and downregulation of activating and inhibitory receptors and increased CD68 expression levels on monocytes/macrophages. Overall, our results indicate that the combination of CUR and RES at low doses differentially shapes immune cells while retaining antitumor activity, support the use of this polyphenol combinations in anticancer therapy and suggest its possible application as adjuvant for NK cell-based immunotherapies.

Interleukin-6 in Hepatocellular Carcinoma: A Dualistic Point of View

Hepatocellular Carcinoma (HCC) is a pressing health concern, demanding a deep understanding of various mediators' roles in its development for therapeutic progress. Notably, interleukin-6 (IL-6) has taken center stage in investigations due to its intricate and context-dependent functions. This review delves into the dual nature of IL-6 in HCC, exploring its seemingly contradictory roles as both a promoter and an inhibitor of disease progression. We dissect the pro-tumorigenic effects of IL-6, including its impact on tumor growth, angiogenesis, and metastasis. Concurrently, we examine its anti-tumorigenic attributes, such as its role in immune response activation, cellular senescence induction, and tumor surveillance. Through a comprehensive exploration of the intricate interactions between IL-6 and the tumor microenvironment, this review highlights the need for a nuanced comprehension of IL-6 signaling in HCC. It underscores the importance of tailored therapeutic strategies that consider the dynamic stages and diverse surroundings within the tumor microenvironment. Future research directions aimed at unraveling the multifaceted mechanisms of IL-6 in HCC hold promise for developing more effective treatment strategies and improving patient outcomes.

Cannabinoid compounds in combination with curcumin and piperine display an anti-tumorigenic effect against colon cancer cells

Currently, use of cannabinoids is limited to improve adverse effects of chemotherapy and their palliative administration during treatment is curiously concomitant with improved prognosis and regressed progression in patients with different tumor types. Although, non-psychoactive cannabidiol (CBD) and cannabigerol (CBG) display antineoplastic effects by repressing tumor growth and angiogenesis both in cell line and animal models, their use as chemotherapeutic agents is awaiting further investigation. Both clinical and epidemiological evidence supported by experimental findings suggest that micronutrients such as curcumin and piperine may present a safer strategy in preventing tumorigenesis and its recurrence. Recent studies demonstrated that piperine potentiates curcumin's inhibitory effect on tumor progression via enhancing its delivery and therapeutic activity. In this study, we investigated a plausible therapeutic synergism of a triple combination of CBD/CBG, curcumin, and piperine in the colon adenocarcinoma using HCT116 and HT29 cell lines. Potential synergistic effects of various combinations including these compounds were tested by measuring cancer cell proliferation and apoptosis. Our findings revealed that different genetic backgrounds of HCT116 and HT29 cell lines resulted in divergent responses to the combination treatments. Triple treatment showed synergism in terms of exhibiting anti-tumorigenic effects by activating the Hippo YAP signaling pathway in the HCT116 cell line.

Co-administration of curcumin with other phytochemicals improves anticancer activity by regulating multiple molecular targets

Natural plant phytochemicals are effective against different types of diseases, including cancer. Curcumin, a powerful herbal polyphenol, exerts inhibitory effects on cancer cell proliferation, angiogenesis, invasion, and metastasis through interaction with different molecular targets. However, the clinical use of curcumin is limited due to poor solubility in water and metabolism in the liver and intestine. The synergistic effects of curcumin with some phytochemicals such as resveratrol, quercetin, epigallocatechin-3-gallate, and piperine can improve its clinical efficacy in cancer treatment. The present review specifically focuses on anticancer mechanisms related to the co-administration of curcumin with other phytochemicals, including resveratrol, quercetin, epigallocatechin-3-gallate, and piperine. According to the molecular evidence, the phytochemical combinations exert synergistic effects on suppressing cell proliferation, reducing cellular invasion, and inducing apoptosis and cell cycle arrest. This review also emphasizes the significance of the co-delivery vehicles-based nanoparticles of such bioactive phytochemicals that could improve their bioavailability and reduce their systemic dose. Further high-quality studies are needed to firmly establish the clinical efficacy of the phytochemical combinations.

Curcumin in the treatment of liver cancer: From mechanisms of action to nanoformulations

Liver cancer is the sixth most prevalent cancer and ranks third in cancer-related death, after lung and colorectal cancer. Various natural products have been discovered as alternatives to conventional cancer therapy strategies, including radiotherapy, chemotherapy, and surgery. Curcumin (CUR) with antiinflammatory, antioxidant, and antitumor activities has been associated with therapeutic benefits against various cancers. It can regulate multiple signaling pathways, such as PI3K/Akt, Wnt/β-catenin, JAK/STAT, p53, MAPKs, and NF-ĸB, which are involved in cancer cell proliferation, metastasis, apoptosis, angiogenesis, and autophagy. Due to its rapid metabolism, poor oral bioavailability, and low solubility in water, CUR application in clinical practices is restricted. To overcome these limitations, nanotechnology-based delivery systems have been applied to use CUR nanoformulations with added benefits, such as reducing toxicity, improving cellular uptake, and targeting tumor sites. Besides the anticancer activities of CUR in combating various cancers, especially liver cancer, here we focused on the CUR nanoformulations, such as micelles, liposomes, polymeric, metal, and solid lipid nanoparticles, and others, in the treatment of liver cancer.

Qi Ling decoction enhances abiraterone treatment via suppression of autophagy in castration resistant prostate cancer

Abiraterone acetate has exhibited impressive results in improving progression-free survival of patients with metastatic castration-resistant prostate cancer. However, many patients may develop abiraterone resistance with a variable duration of response. Hence, identifying a remedy to overcome abiraterone resistance is critical for patients with castration-resistant prostate cancer. In this study, we aim to explore the potential of Qi Ling decoction (QLD), a traditional Chinese medicine, in attenuating abiraterone resistance in prostate cancer. Cell viability and apoptosis were respectively measured by Cell Counting Kit-8 (CCK-8) assay and flow cytometry. The protein levels were assessed by Western blotting assay. Autophagosome formation was quantified by counting LC3 puncta. We found that QLD was capable of promoting abiraterone-induced apoptosis and cell death of PC3-AbiR and DU145-AbiR cells in vitro. A combination of QLD and abiraterone yielded a better tumor inhibition effect than QLD alone and abiraterone alone. Further investigation revealed that QLD restored the abiraterone sensitivity of PC3-AbiR and DU145-AbiR cells through modulating autophagy. These findings suggest that QLD might serve as a potential remedy to enhance the therapeutical effect of abiraterone for patients with castration-resistant prostate cancer.

Strategies for Improving Bioavailability, Bioactivity, and Physical-Chemical Behavior of Curcumin

Curcumin (CCM) is one of the most frequently explored plant compounds with various biological actions such as antibacterial, antiviral, antifungal, antineoplastic, and antioxidant/anti-inflammatory properties. The laboratory data and clinical trials have demonstrated that the bioavailability and bioactivity of curcumin are influenced by the feature of the curcumin molecular complex types. Curcumin has a high capacity to form molecular complexes with proteins (such as whey proteins, bovine serum albumin, β-lactoglobulin), carbohydrates, lipids, and natural compounds (e.g., resveratrol, piperine, quercetin). These complexes increase the bioactivity and bioavailability of curcumin. The current review provides these derivatization strategies for curcumin in terms of biological and physico-chemical aspects with a strong focus on different type of proteins, characterization methods, and thermodynamic features of protein–curcumin complexes, and with the aim of evaluating the best performances. The current literature review offers, taking into consideration various biological effects of the CCM, a whole approach for CCM-biomolecules interactions such as CCM-proteins, CCM-nanomaterials, and CCM-natural compounds regarding molecular strategies to improve the bioactivity as well as the bioavailability of curcumin in biological systems.

Ferroptosis-induced anticancer effect of resveratrol with a biomimetic nano-delivery system in colorectal cancer treatment

Ferroptosis is a novel form of programmed cell death impelled by iron-dependent lipid peroxidation, which may be a potential strategy for cancer therapy. Here we demonstrated for the first time that Resveratrol (RSV), a traditional Chinese medicine (TCM) chemical monomer, could effectually inhibit the growth of colon cancer cells through the ROS-dependent ferroptosis pathway. Mechanistically, RSV evoked the increase of reactive oxygen species and lipid peroxidation in colorectal cancer cells, and eventually lead to ferroptosis. Furthermore, RSV could promote ferroptosis by downregulating the expression of the channel protein solute carrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4). To improve the delivery efficiency of RSV, a biomimetic nanocarrier was developed by coating RSV-loaded poly(ε-caprolactone)–poly(ethylene glycol) (PCL-PEG) nanoparticles with erythrocyte membrane (RSV-NPs@RBCm). The RSV-NPs@RBCm provide the possibility to escape macrophage phagocytosis and have a long circulation effect. In addition, when coupled with a tumor-penetrating peptide iRGD, which could trigger enhanced tissue penetration tumor-specifically, the delivery of RSV-NPs@RBCm into tumors would be significantly improved results from the in vivo study demonstrated an excellent treatment efficacy for CRC. Altogether, our study highlighted the therapeutic potential of RSV as a ferroptosis-inducing anticancer agent and when loaded into a biomimetic nanoplatform, it might pave the way for the application of RSV loaded nanosystems for colorectal cancer treatment.

Bioactive Effects of Curcumin in Human Immunodeficiency Virus Infection Along with the Most Effective Isolation Techniques and Type of Nanoformulations

Human immunodeficiency virus (HIV) is one of the leading causes of death worldwide, with African countries being the worst affected by this deadly virus. Curcumin (CUR) is a Curcuma longa-derived polyphenol that has attracted the attention of researchers due to its antimicrobial, anti-inflammatory, antioxidant, immunomodulatory and antiviral effects. CUR also demonstrates anti-HIV effects by acting as a possible inhibitor of gp120 binding, integrase, protease, and topoisomerase II activities, besides also exerting a protective action against HIV-associated diseases. However, its effectiveness is limited due to its poor water solubility, rapid metabolism, and systemic elimination. Nanoformulations have been shown to be useful to enhance curcumin’s bioavailability and its effectiveness as an anti-HIV agent. In this sense, bioactive effects of CUR in HIV infection are carefully reviewed, along with the most effective isolation techniques and type of nanoformulations available.

3D printed MCT oleogel as a co-delivery carrier for curcumin and resveratrol

Designing a suitable matrix to protect sensitive bioactive compounds is an important stage in nutraceutical development. In this study, emulsion templated medium-chain triglycerides (MCT) oleogel was developed as co-delivery carriers for synergistic nutraceuticals, curcumin, and resveratrol and to 3D print in customized shapes for personalized nutrition. To obtain the stable emulsion, gelatin and gellan gum were added such that their protein-polysaccharide interaction helps in the structuring of the oil phase. Increasing the amount of gellan gum had a positive effect on stabilizing the emulsion but became the critical parameter during 3D printing. Hence, gellan gum of 1.5% (w/v) and gelatin at 10% (w/v) of water were considered optimum to produce a stable 30% O/W emulsion for 3D printing. Upon analyzing the in-vitro digestion behavior of the oleogel, it was observed that the bioactives were protected under oral and gastric conditions and allowed intestinal targeted delivery. The total bioaccessible fraction increased up to 1.13-fold and 1.2-fold for curcumin and resveratrol respectively compared to control (MCT oil). The FFAs release profile also indicated that gelators play an important role in lipase activity. Also, the ex-vivo everted gut sac analysis showed enhanced permeation of about 1.83 times and 1.13 times for curcumin and resveratrol respectively. Thus, this study provides useful insights into the 3D printing of emulsion templated oleogel as personalized nutraceutical carriers.

Applications of resveratrol in the treatment of gastrointestinal cancer

Natural product compounds have lately attracted interest in the scientific community as a possible treatment for gastrointestinal (GI) cancer, due to their anti-inflammatory and anticancer properties. There are many preclinical, clinical, and epidemiological studies, suggesting that the consumption of polyphenol compounds, which are abundant in vegetables, grains, fruits, and pulses, may help to prevent various illnesses and disorders from developing, including several GI cancers. The development of GI malignancies follows a well-known path, in which normal gastrointestinal cells acquire abnormalities in their genetic composition, causing the cells to continuously proliferate, and metastasize to other sites, especially the brain and liver. Natural compounds with the ability to affect oncogenic pathways might be possible treatments for GI malignancies, and could easily be tested in clinical trials. Resveratrol is a non-flavonoid polyphenol and a natural stilbene, acting as a phytoestrogen with anti-cancer, cardioprotective, anti-oxidant, and anti-inflammatory properties. Resveratrol has been shown to overcome resistance mechanisms in cancer cells, and when combined with conventional anticancer drugs, could sensitize cancer cells to chemotherapy. Several new resveratrol analogs and nanostructured delivery vehicles with improved anti-GI cancer efficacy, absorption, and pharmacokinetic profiles have already been developed. This present review focuses on the in vitro and in vivo effects of resveratrol on GI cancers, as well as the underlying molecular mechanisms of action.

Beneficial Oxidative Stress-Related trans-Resveratrol Effects in the Treatment and Prevention of Breast Cancer

Resveratrol is one of the most investigated polyphenols for its multiple biological activities and many beneficial effects. These are mainly related to its ability to scavenge free radicals and reduce oxidative stress. Resveratrol has also been shown to have the ability to stimulate the production of antioxidant enzymes, which interact with numerous signaling pathways involved in tumor development, and to possess side effects associated with the use of chemotherapy drugs. In this review article we summarized the main discoveries about the impact resveratrol can have in helping to prevent, as well as adjuvant treating, breast cancer. A brief overview of the primary sources of resveratrol as well as some approaches for improving its bioavailability have been also discussed.

Nanoencapsulation of Polyphenols as Drugs and Supplements for Enhancing Therapeutic Profile - A Review

Polyphenolic phytoconstituents have been widely in use worldwide since ages and are categorised as secondary metabolites of plants. The application of polyphenols such as quercetin, resveratrol. curcumin as nutritional supplement has been researched widely. The use of polyphenols, and specifically quercetin for improving the memory and mental endurance have shown significant effects among rats. Even though similar results has not been resonated among human but encouraging preclinical results have encouraged researchers to explore other polyphenols to study the effects as supplements among athletes. The phytopharmacological research has elucidated the use of natural polyphenols to prevent and treat various physiological and metabolic disorders owing to its free radical scavenging properties, anti-inflammatory, anti-cancer and immunomodulatory effects. In spite of the tremendous pharmacological profile, one of the most dominant problem regarding the use of polyphenolic compounds is their low bioavailability. Nanonization is considered as one of the most prominent approaches among many. This article aims to review and discuss the molecular mechanisms of recently developed nanocarrier-based drug delivery systems for polyphenols and its application as drugs and supplements. Nanoformulations of natural polyphenols are bioactive agents, such as quercetin, kaempferol, fisetin, rutin, hesperetin, and naringenin epigalloccatechin-3-gallate, genistein, ellagic acid, gallic acid, chlorogenic acid, ferulic acid, curcuminoids and stilbenes is expected to have better efficacy. These delivery systems are expected to provide higher penetrability of polyphenols at cellular levels and exhibit a controlled release of the drugs. It is widely accepted that natural polyphenols do demonstrate significant therapeutic effect. However, the hindrances in their absorption, specificity and bioavailability can be overcome using nanotechnology.

Synergistic Protective Effect of Curcumin and Resveratrol against Oxidative Stress in Endothelial EAhy926 Cells

Curcumin (C) and resveratrol (R) are two well-known nutraceuticals with strong antioxidant activity that can protect cells from oxidative stress. This study aims to investigate the synergy of CR combinations in protecting human endothelial EAhy926 cells against H₂O₂-induced oxidative stress and its related mechanisms. C and R as individual compounds as well as CR combinations at different ratios were screened for their protective effects against H₂O₂ (2.5 mM) induced cell death assessed by cell viability assays. The synergistic interaction was analysed using the combination index model. The effects of optimal CR combinations on caspase-3 activity, ROS level, SOD activity, NAD cellular production, expression of Nrf2 and HO-1, and Nrf2 translocation were determined. CR combinations produced a synergistic protection against that of H₂O₂-induced changes in cell viability, caspase-3 activity, and ROS production. The strongest effect was observed for CR with the ratio of 8 : 2. Further experiments showed that CR 8 : 2 exhibited significantly greater effects in increasing Nrf2 translocation and expressions of Nrf2 and HO-1 proteins, as well as SOD activity and total cellular NAD production, than that of C or R alone. The findings demonstrate that combination of C and R produced a strong synergy in activity against H₂O₂-induced oxidative stress in EAhy926 cells. The mechanism of this synergy involves the activation of Nrf2-HO-1 signaling pathway and promotion of antioxidant enzymes. Further studies on CR synergy may help develop a new combination therapy for endothelial dysfunction and other conditions related to oxidative stress.

Chemo-Preventive Action of Resveratrol: Suppression of p53-A Molecular Targeting Approach

Extensive experimental, clinical, and epidemiological evidence has explained and proven that products of natural origin are significantly important in preventing and/or ameliorating various disorders, including different types of cancer that researchers are extremely focused on. Among these studies on natural active substances, one can distinguish the emphasis on resveratrol and its properties, especially the potential anticancer role. Resveratrol is a natural product proven for its therapeutic activity, with remarkable anti-inflammatory properties. Various other benefits/actions have also been reported, such as cardioprotective, anti-ageing, antioxidant, etc. and its rapid digestion/absorption as well. This review aims to collect and present the latest published studies on resveratrol and its impact on cancer prevention, molecular signals (especially p53 protein participation), and its therapeutic prospects. The most recent information regarding the healing action of resveratrol is presented and concentrated to create an updated database focused on this topic presented above.

Dietary polyphenols in chemoprevention and synergistic effect in cancer: Clinical evidences and molecular mechanisms of action

BACKGROUND

Epidemiological studies has revealed that a diet rich in fruits and vegetables could lower the risk of certain cancers. In this setting, natural polyphenols are potent anticancer bioactive compounds to overcome the non-target specificity, undesirable cytotoxicity and high cost of treatment cancer chemotherapy.

PURPOSE

The review focuses on diverse classifications of the chemical diversity of dietary polyphenol and their molecular targets, modes of action, as well as preclinical and clinical applications in cancer prevention.

RESULTS

The dietary polyphenols exhibit chemo-preventive activity through modulation of apoptosis, autophagy, cell cycle progression, inflammation, invasion and metastasis. Polyphenols possess strong antioxidant activity and control multiple molecular events through activation of tumor suppressor genes and inhibition of oncogenes involved in carcinogenesis. Numerous in vitro and in vivo studies have evidenced that these dietary phytochemicals regulate critical molecular targets and pathways to limit cancer initiation and progression. Moreover, natural polyphenols act synergistically with existing clinically approved drugs. The improved anticancer activity of combinations of polyphenols and anticancer drugs represents a promising perspective for clinical applications against many human cancers.

CONCLUSION

The anticancer properties exhibited by dietary polyphenols are mainly attributed to their anti-metastatic, anti-proliferative, anti-angiogenic, anti-inflammatory, cell cycle arrest, apoptotic and autophagic effects. Hence, regular consumption of dietary polyphenols as food or food additives or adjuvants can be a promising tactic to preclude adjournment or cancer therapy.

Synergistic potential of nutraceuticals: mechanisms and prospects for futuristic medicine

Nutraceuticals are valued for their therapeutic effects and numerous health benefits. In recent years, several studies have demonstrated their superior performances when co-delivered; the concept of synergism has been established for various bioactives. Apart from improvements in the bioavailability of partnering compounds, this approach can protect the radical scavenging potential and biological effects of individual compounds. In this review, the intricate mechanisms that promote synergistic effects when bioactive compounds are co-delivered are detailed. Importantly, a range of potential medical applications that have been established through such synergistic effects is presented, emphasizing recent developments in this field. Also, a section has been devoted to highlighting perspectives on co-encapsulation at the nanoscale for improved synergistic benefits. While prospects for the treatment of chronic diseases are well-demonstrated, several challenges and safety concerns remain, and these have been discussed, providing recommendations for future research.

Novel Curcumin-Resveratrol Solid Nanoparticles Synergistically Inhibit Proliferation of Melanoma Cells

Polyphenols such as curcumin (Cur) and resveratrol (Res) have been recently shown to have potential to inhibit proliferation of highly aggressive melanoma cells. This study was designed to investigate the feasibility of a topical delivery system, using a solid lipid nanoparticles (SLNs) loaded delivery systems, that can enhance the skin penetration and anti-cancer efficacy of combination of these polyphenols. Negatively charged Cur-Res SLNs with a mean diameter of 180.2 ± 7.7 nm were prepared using high shear homogenization method. Cur-Res SLNs were found to be stable up to 2 weeks under 4°C. The in vitro release study showed that Res was released five time more than curcumin. The permeability of resveratrol was about 1.67 times that of curcumin from the SLN-gel formulation which was significantly (p < 0.05) lower than from SLN suspension. More than 70% of Cur-Res SLNs were bound to skin locally in a skin binding study suggesting potentially utility of Cur-Res SLNs in the treatment of localized melanoma. In fact, the electrical cell-substrate impedance sensing (ECIS) measurements suggested that Cur-Res combination has potential to stop cell migration of B16F10 melanoma cells. Furthermore, both, Cur-Res SLNs and Cur-Res solution at the ratio of 3:1 demonstrated a strong synergistic inhibition of SK-MEL-28 melanoma cell proliferation. Further evaluation of Cur-Res SLNs in vivo melanoma models are warranted to establish the clinical utility of Cur-Res formulations in melanoma therapy.

Free Radicals as a Double-Edged Sword: The Cancer Preventive and Therapeutic Roles of Curcumin

Free radicals, generally composed of reactive oxygen species (ROS) and reactive nitrogen species (RNS), are generated in the body by various endogenous and exogenous systems. The overproduction of free radicals is known to cause several chronic diseases including cancer. However, increased production of free radicals by chemotherapeutic drugs is also associated with apoptosis in cancer cells, indicating the dual nature of free radicals. Among various natural compounds, curcumin manifests as an antioxidant in normal cells that helps in the prevention of carcinogenesis. It also acts as a prooxidant in cancer cells and is associated with inducing apoptosis. Curcumin quenches free radicals, induces antioxidant enzymes (catalase, superoxide dismutase, glutathione peroxidase), and upregulates antioxidative protein markers-Nrf2 and HO-1 that lead to the suppression of cellular oxidative stress. In cancer cells, curcumin aggressively increases ROS that results in DNA damage and subsequently cancer cell death. It also sensitizes drug-resistant cancer cells and increases the anticancer effects of chemotherapeutic drugs. Thus, curcumin shows beneficial effects in prevention, treatment and chemosensitization of cancer cells. In this review, we will discuss the dual role of free radicals as well as the chemopreventive and chemotherapeutic effects of curcumin and its analogues against cancer.

Cordycepin induces apoptosis in human tongue cancer cells in vitro and has antitumor effects in vivo

OBJECTIVE

This study was designed to explore the ability of cordycepin to disrupt human tongue cancer cell growth, and to assess the mechanistic basis for such anti-cancer activity.

METHODS

CAL-27 human tongue cancer cells were treated with cordycepin prior to analysis via CCK-8 assay in order to assess their proliferation. In addition, cell cycle progression and apoptotic death in these cells were measured via flow cytometry, while the expression of apoptosis-associated genes and proteins (caspase-3, caspase-9, caspase-12, Bcl-2, and Bax) were measured via real-time PCR and western blotting. We further measured the intracellular production of reactive oxygen species (ROS) and used a murine xenograft model system to explore the in vivo anti-tumor activity of cordycepin.

RESULTS

Cordycepin was able to significantly suppress the proliferation of CAL-27 cells in a dose-dependent fashion (IC₅₀ = 40 μg/mL at 24 h). Cordycepin further induced Bax, caspase-3, caspase-9, and caspase-12 upregulation at the mRNA and protein levels while simultaneously downregulating anti-apoptotic Bcl-2 expression. CAL-27 cells treated using cordycepin also exhibited elevated levels of intracellular ROS. Importantly, cordycepin was able to effectively suppress tongue cancer tumor growth in a murine xenograft model system and similar mRNA and protein levels were observed in vivo.

CONCLUSIONS

Cordycepin can inhibit human tongue cancer cell growth and can drive their apoptotic death via the mitochondrial pathway. In addition, cordycepin can suppress tongue cancer growth in vivo in treated mice.

Nanoencapsulated dietary polyphenols for cancer prevention and treatment: successes and challenges

Many dietary polyphenols have been investigated for their therapeutic potential either as single agents or in combinations. Despite the significant anticancer potential of these polyphenols in in vitro cell culture and in vivo animal models, their clinical applications have been limited because of challenges such as ineffective systemic delivery, stability and low bioavailability. Nanoencapsulation of these polyphenols could prolong circulation, improve localization, enhance efficacy and reduce the chances of multidrug resistance. This review summarized the use of various polyphenols especially epigallocatechin gallate, quercetin, curcumin and resveratrol as nanoformulations for cancer prevention and treatment. Despite some success, more research is warranted to design a nanoencapsulated combination of polyphenols, effective in in vitro, in vivo and human systems.

Liposome co-encapsulation as a strategy for the delivery of curcumin and resveratrol

Curcumin and resveratrol are natural compounds whose strong antioxidant activities are highly beneficial in the human diet. Unfortunately, their physicochemical properties result in poor stability in their chemical and antioxidant activities, which limits their utilization in food and pharmaceutical applications. In this study, liposomal nanoencapsulation was developed as a strategy to overcome these limitations and improve the antioxidant effects of these compounds. The physicochemical characteristics of co-encapsulated liposomes were evaluated and compared to formulations containing each compound individually. Liposomes co-encapsulating curcumin and resveratrol presented a lower particle size, lower polydispersity index and greater encapsulation efficiency. The formulation of liposomes co-loading curcumin and resveratrol at 5 : 1, exhibited the lowest particle size (77.50 nm), lowest polydispersity index (0.193), highest encapsulation efficiency (reaching 80.42 ± 2.12%), and strongest 2,2-diphenyl-1-picrylhydrazyl scavenging, lipid peroxidation inhibition capacity and reducing power. Additionally, liposomes loading both curcumin and resveratrol displayed a higher ability during preparation, storage, heating and surfactant shock than those loaded with individual polyphenol. Infrared spectroscopic and fluorescence techniques demonstrated that the curcumin mainly located in the hydrophobic acyl-chain region of liposomes, while the resveratrol orientated to the polar head groups. These orientations could have synergistic effects on the stabilization of liposomes. Our findings should guide the rational design of a co-delivery liposomal system regarding the location and orientation of bioactive compounds inside the lipid bilayer.

Curcumin- and Piperine-Loaded Emulsomes as Combinational Treatment Approach Enhance the Anticancer Activity of Curcumin on HCT116 Colorectal Cancer Model

Combination chemotherapy, administrating two chemotherapeutic agents concurrently, comes into prominence, as the heterogeneity or the level of the disease necessitates a collaborative action. Curcumin, isolated from turmeric, and piperine, isolated from black long pepper, are two dietary polyphenols studied for their intrinsic anti-cancer properties against various cancer types including colorectal cancer (CRC). Furthermore, piperine improves the therapeutic effect of curcumin. Addressing this mutual behavior, this study combines curcumin and piperine within emulsome nanoformulations. Curcumin- (CurcuEmulsomes) and piperine-loaded emulsomes (PiperineEmulsomes) have established a uniform, stable, spherical dispersion with average diameters of 184.21 and 248.76 nm, respectively. The solid tripalmitin inner core achieved encapsulation capacities of up to 0.10 mg/ml curcumin and 0.09 mg/ml piperine content. While piperine treatment alone - in its both free and emulsome forms - showed no inhibition in the proliferation of HCT116 cells in vitro, its presence as the second drug agent enhanced curcumin's effect. Combination of 7 μM PiperineEmulsome and 25 μM CurcuEmulsome concentrations was found to be most effective with an inhibition of cell proliferation of about 50% viability. Cell cycle arrest at G2/M phase and induced apoptosis verified the improved anti-cancer characteristics of the therapy. While CurcuEmulsomes achieved a fourfold increase in Caspase 3 level, combination of treatment with PiperineEulsomes achieved a sixfold increase in the level of this apoptotic marker. Combinational treatment of HCT116 cells with CurcuEmulsomes and PiperineEmulsomes improved the anticancer activity of the compounds and highlighted the potential of the approach for further in vivo studies.

Pro-apoptotic genes as new targets for single and combinatorial treatments with resveratrol and curcumin in colorectal cancer

Colorectal cancer (CRC) represents the third most diagnosed type of cancer worldwide with high mortality and an increased incidence rate. Bioactive dietary components such as curcumin and resveratrol have great therapeutic potential as they can modulate a plethora of signaling pathways related to colorectal carcinogenesis. Previous data have demonstrated that curcumin and resveratrol can induce apoptosis in different types of cancer cells. Considering the lack of data on the combinatorial effect of curcumin and resveratrol associated with the induction of apoptosis in colorectal pathology, the main objective of this study is to investigate the impact of single vs. combinatorial treatment of resveratrol and curcumin on their cytotoxic effects, as well as the modulation of several essential pro-apoptotic genes, on two colorectal cancer cell lines (DLD-1 and Caco-2) different in terms of chromosomal stability (MSI and MSS). The cytotoxic effects were evaluated by the MTT assay, the nature of the interaction between curcumin and resveratrol was assessed by the combination index method and the expression levels of key genes involved in the modulation of pro-apoptotic mechanisms were evaluated by RT-qPCR. Our data indicate that the combination treatment of curcumin and resveratrol is more effective in inhibiting the proliferation in a dose-dependent manner, with a synergistic effect for the DLD-1 cell line (CI < 1) and an additive effect for the Caco-2 cell line (CI ≥ 1). The IC50 values for the combination treatment were 71.8 μM (20.5 μM curcumin + 51.3 μM resveratrol) for the DLD-1 cell line and 66.21 μM (18.9 μM curcumin + 47.3 μM resveratrol) for the Caco-2 cell line, respectively. Our data pointed out, for the first time, that several genes involved in the modulation of apoptosis, including PMAIP1, BID, ZMAT3, CASP3, CASP7, and FAS, represent new targets of both singular and combinatorial treatments with resveratrol and curcumin, and also the combinatorial approach of curcumin and resveratrol exhibits a more powerful gene regulating effect compared to single treatment. Considering the beneficial aspects of the combinatorial approach with curcumin and resveratrol on colorectal cancer cells further studies should address the possible pharmacological benefits of using a combination of both dietary agents with different chemotherapeutic drug approaches.

A Stilbenoid Isorhapontigenin as a Potential Anti-Cancer Agent against Breast Cancer through Inhibiting Sphingosine Kinases/Tubulin Stabilization

Isorhapontigenin (ISO), a tetrahydroxylated stilbenoid, is an analog of resveratrol (Rsv). The various biological activities of Rsv and its derivatives have been previously reported in the context of both cancer and inflammation. However, the anti-cancer effect of ISO against breast cancer has not been well established, despite being an orally bioavailable dietary polyphenol. In this study, we determine the anti-cancer effects of ISO against breast cancer using MCF7, T47D, and MDA-MB-231 cell lines. We observed that ISO induces breast cancer cell death, cell cycle arrest, oxidative stress, and the inhibition of cell proliferation. Additionally, sphingosine kinase inhibition by ISO controlled tubulin polymerization and cancer cell growth by regulating MAPK/PI3K-mediated cell cycle arrest in MCF7 cells. Interestingly, SPHK1/2 gene silencing increased oxidative stress, cell death, and tubulin destabilization in MCF7 cells. This suggests that the anti-cancer effect of ISO can be regulated by SPHK/tubulin destabilization pathways. Overall, ISO successfully induced breast cancer cell death and cell growth arrest, suggesting this phytochemical is a better alternative for breast cancer treatment. Further studies in animal models could confirm the potency and usability of ISO over Rsv for targeting breast cancer, potentially posing an alternative candidate for improved therapy in the near future.

The use of curcumin as an effective adjuvant to cancer therapy: A short review

Turmeric (Curcuma longa) is a popular spice that has been used in Ayurvedic medicine for its ability to treat various common ailments. There have been statistical correlations between turmeric consumption and lower incidences of cancer development, prompting research into its primary component curcumin. Several in vitro and in vivo studies over the last decade into cancer treatment have provided experimental evidence that curcumin contains antiproliferative, antiangiogenic, and apoptotic properties. The results of human clinical trials however, have proven mostly to be inconclusive. This short review provides an insight into the properties of curcumin including its bioavailability, biological activity, and potential usage in clinical trials as a chemotherapeutic drug.

Resveratrol As A Natural Regulator Of Autophagy For Prevention And Treatment Of Cancer

Resveratrol, as a natural product compound, has been recently attracted much attention for its potent effects on cancer. Cancer is a serious disease threatening human survival and social development. Autophagy is a cellular pathway to realize the metabolic needs of the cell itself and the renewal of some organelles and plays opposing, context-dependent role in tumorigenesis. So the regulation of autophagy is of great significance in the treatment of cancer. p62, as an autophagy adaptor protein, is a preferred target for autophagy and is constantly controlled by constitutive autophagy. As a tumor-suppression mechanism, autophagy deficiency is common in tumors, which results in aberrant accumulation of p62 and activates p62-regulated pathways, such as activation of mTOR in nutrient sensing, and the activation of the Keap1-Nrf2 pathway for antioxidant stress, which are associated with cancer development. In this review, we emphasize that resveratrol can induce autophagy in the treatment of cancer and accelerates the degradation of p62, and then, the mTOR activation is blocked and Nrf2 activation is suppressed. As a result, the multidrug resistance of cancer cells can be reversed by resveratrol.

Traditional Chinese medicine formulation Yanggan Jiedu Sanjie inhibits TGF-β1-induced epithelial-mesenchymal transition and metastatic potential in human hepatocarcinoma Bel-7402 cells

BACKGROUND

Epithelial-mesenchymal transition (EMT) is a vital process in cancer progression and metastasis. Yanggan Jiedu Sanjie (YGJDSJ) is Traditional Chinese Medicine formulation for liver cancer treatment. In the present study, we evaluated the effects of YGJDSJ on TGF-β1-induced EMT in hepatocellular carcinoma Bel-7402 cells.

METHODS

Bel-7402 cells were treated with TGF-β1 and YGJDSJ. EMT was identified by morphological changes and expression of marker proteins. Cell morphology was observed under a microscope. Protein expression and phosphorylation was detected by western blotting. Cell migration was measured by the scratch assay. Cell adhesion and invasion was detected by a commercial kit.

RESULTS

YGJDSJ reversed TGF-β1-induced morphological changes, as well as the expression of the EMT markers E-cadherin and N-cadherin in Bel-7402 cells. YGJDSJ also inhibited TGF-β1 up-regulated Smad3 phosphorylation and Snail expression in Bel-7402 cells. Moreover, YGJDSJ inhibited TGF-β1-induced cell adhesion, migration and invasion in Bel-7402 cells.

CONCLUSIONS

YGJDSJ inhibited TGF-β1-induced EMT and mediated metastatic potential of Bel-7402 cells, which may be related to down-regulation of Smad3 phosphorylation and Snail expression. The present study provides a new basis for application of this herbal formula for prevention of liver cancer metastasis.

Impact of chronic kidney dysfunction on serum Sulfatides and its metabolic pathway in mice

Serum sulfatides are critical glycosphingolipids that are present in lipoproteins and exert anticoagulant effects. A previous study reported decreased levels of serum sulfatides in hemodialysis patients and suggested an association with cardiovascular disease. However, the mechanism of changes in serum sulfatides in chronic kidney dysfunction has not been well investigated. The current study examined whether a chronic kidney disease (CKD) state could decrease serum sulfatide levels using 5/6 nephrectomy (5/6NCKD) mice, an established CKD murine model, and studied the mechanisms contributing to diminished sulfatides. 5/6NCKD mice and sham operation control mice were sacrificed at the 4th or 12th postoperative week (POW) for measurement of serum sulfatide levels. Hepatic sulfatide content, which is the origin of serum sulfatides, and the expression of sulfatide metabolic enzymes in liver tissue were assessed as well. The 5/6NCKD mice developed CKD and showed increased serum creatinine and indoxyl sulfate. The serum levels and hepatic amounts of sulfatides were significantly decreased in 5/6NCKD mice at both 4 and 12 POW, while the degradative enzymes of sulfatides arylsulfatase A and galactosylceramidase were significantly increased. In a Hepa1-6 murine liver cell line, indoxyl sulfate addition caused intracellular levels of sulfatides to decrease and degradative enzymes of sulfatides to increase in a manner comparable to the changes in 5/6NCKD mice liver tissue. In conclusion, chronic kidney dysfunction causes degradation of sulfatides in the liver to decrease serum sulfatide levels. One explanation of these results is that indoxyl sulfate, a uremic toxin, accelerates the degradation of sulfatides in liver tissue.

Downregulation of glucose-regulated protein 78 enhances the cytotoxic effects of curcumin on human nasopharyngeal carcinoma cells

Curcumin is a conventional Chinese medicine, which exerts a marked effect on various tumor types and suppresses tumor invasion. The present study analyzed the antineoplastic effects of curcumin on human nasopharyngeal carcinoma (NPC) cells and determined the effects of endoplasmic reticulum (ER) stress on curcumin‑induced cytotoxicity. The Cell Counting Kit‑8 assay examined the viability of SUNE1 and SUNE2 NPC cells. The Annexin V/propidium iodide staining technique was used to detect cell apoptosis and flow cytometry was used to examine cell cycle distribution. Western blotting and immunofluorescence were used to detect ER stress‑associated molecules. Furthermore, the toxic effects of curcumin treatment alongside glucose‑regulated protein 78 (GRP78) knockdown using small interfering (si)RNA, and treatment with the pan‑caspase inhibitor Z‑VAD‑FMK and the protein kinase B (AKT) inhibitor MK‑2206 were detected. The results demonstrated that curcumin markedly reduced cell viability, blocked cell cycle progression and induced apoptosis of human NPC cells. In addition, curcumin activated ER stress‑associated proteins to participate in the apoptosis of human NPC cells. siRNA‑induced knockdown of GRP78 may be able to strengthen the toxic effects of curcumin through mediating the AKT signaling pathway. These findings indicated that downregulation of GRP78 promoted the therapeutic effects of curcumin on NPC cells. The present study identified a potential, novel therapeutic method for the treatment of NPC.

Synergistic antiproliferative effects of curcumin and celecoxib in hepatocellular carcinoma HepG2 cells

Hepatocellular carcinoma (HCC) is still a leading cancer killer in the community. Molecular targeted therapy with celecoxib (CXB) has shown promising antitumor effects; however, its use may be limited due to serious side effects. Curcumin (CUR) has also shown beneficial effects against HCC. Then, it was aimed to investigate the effects of adding CUR to CXB on HCC HepG2 cells. HepG2 cells were treated with CXB and/or CUR at increasing concentrations to investigate synergistic drug interactions, as calculated combination index (CI). Combination treatment effects on cell viability and caspase-3 activation were assessed. The levels of Akt, nuclear factor-kappa B (NF-κB), prostaglandin E₂ (PGE₂), malondialdehyde (MDA), cyclin D1 (CD1), and vascular endothelial growth factor (VEGF) were also evaluated. CXB (3.13-100 μM) and/or CUR (1.25-40 μM) reduced HepG2 cell viability dose-dependently. Nevertheless, lower combined concentrations showed higher synergism (CI < 1) and higher CXB dose reduction index (DRI > 1). Also, the addition of CUR to CXB resulted in increased cytotoxicity and caspase-3 activation, as compared to CXB alone. In addition, the selected combination significantly reduced the levels of Akt, NF-κB, PGE₂, MDA, CD1, and VEGF, as compared to either agent alone. In conclusion, CUR augmented the CXB-mediated antitumor effects in HepG2 cells through, at least in part, antiproliferative, antioxidant, and pro-apoptotic mechanisms. This may allow the further use of CXB at lower concentrations, combined with CUR, as a promising safer targeted strategy for HCC management.

Inhibition of PI3K/Akt/mTOR pathway by apigenin induces apoptosis and autophagy in hepatocellular carcinoma cells

Apigenin is a dietary flavonoid with known antioxidant and antitumor effects against several types of cancers by promoting cell death and inducing cell cycle arrest. Apigenin also regulates a variety of intracellular signal transduction pathways during apoptosis or autophagy. However, the precise mechanism underlying the anticancer effects of apigenin in liver cancer remains poorly understood. In this study, we demonstrated that apigenin has anticancer activity against hepatocellular carcinoma cells. Apigenin inhibited the cell growth and induced cell death in a dose- and time-dependent manner in HepG2 cells. We found that apigenin treatment increased the expression of LC3-II and the number of GFP-LC3 puncta. Moreover, inhibition of autophagy with 3-MA and Atg5 gene silencing strengthened apigenin-induced proliferation inhibition and apoptosis. Our data has indicated that apigenin-induced autophagy has a protective effect against cell death. Additionally, apigenin induced apoptosis and autophagy through inhibition of PI3K/Akt/mTOR pathway. Most importantly, in vivo data showed that administration of apigenin decreased tumor growth and autophagy inhibition by 3-MA significantly enhanced the anticancer effect of apigenin. Collectively, our results reveal that apigenin inhibits cell proliferation and induces autophagy via suppressing the PI3K/Akt/mTOR pathway. Our results also suggest combination of autophagy inhibitors and apigenin would be a potential chemotherapeutic strategy against hepatocellular carcinoma.

Effects of resveratrol, curcumin, berberine and other nutraceuticals on aging, cancer development, cancer stem cells and microRNAs

Natural products or nutraceuticals have been shown to elicit anti-aging, anti-cancer and other health-enhancing effects. A key target of the effects of natural products may be the regulation of microRNA (miR) expression which results in cell death or prevents aging, diabetes, cardiovascular and other diseases. This review will focus on a few natural products, especially on resveratrol (RES), curcumin (CUR) and berberine (BBR). RES is obtained from the skins of grapes and other fruits and berries. RES may extend human lifespan by activating the sirtuins and SIRT1 molecules. CUR is isolated from the root of turmeric (Curcuma longa). CUR is currently used in the treatment of many disorders, especially in those involving an inflammatory process. CUR and modified derivatives have been shown to have potent anti-cancer effects, especially on cancer stem cells (CSC). BBR is also isolated from various plants (e.g., Coptis chinensis) and has been used for centuries in traditional medicine to treat diseases such as adult- onset diabetes. Understanding the benefits of these and other nutraceuticals may result in approaches to improve human health.

Nano-encapsulated metformin-curcumin in PLGA/PEG inhibits synergistically growth and hTERT gene expression in human breast cancer cells

The study was aimed at investigating the synergistic inhibitory effect of unique combinational regimen of nanocapsulated Metformin (Met) and Curcumin (Cur) against T47D breast cancer cells. For this purpose, Met and Cur were co-encapsulated in PEGylated PLGA nanoparticles (NPs) and evaluated for their therapeutic efficacy. The morphology and dynamic light scattering (DLS) analyses were carried out to optimize the nanoformulations. Drug release study was performed using dialysis method and then the cytotoxic and inhibitory effect of individual and combined drugs on expression level of hTERT in T47D breast cell line were evaluated using MTT assay and qPCR, respectively. The results showed that free drugs and formulations exhibited a dose-dependent cytotoxicity against T47D cells and especially, Met-Cur-PLGA/PEG NPs had more synergistic antiproliferative effect and significantly arrested the growth of cancer cells than the other groups (p < .05). Real-time PCR results revealed that Cur, Met and combination of Met-Cur in free and encapsulated forms inhibited hTERT gene expression. It was found that Met-Cur-PLGA/PEG NPs in relative to free combination could further decline hTERT expression in all concentration (p < .05). Taken together, our study demonstrated that Met-Cur-PLGA/PEG NPs based combinational therapy holds promising potential towards the treatment of breast cancer.

Nutrigenomics in cancer: Revisiting the effects of natural compounds

Nutrigenomics effects have an important role in the manipulation of dietary components for human benefit, particularly in cancer prevention or treatment. The impact of dietary components, including phytochemicals, is largely studied by nutrigenomics, looking at the gene expression and molecular mechanisms interacting with bioactive compounds and nutrients, based on new 'omics' technologies. The high number of preclinical studies proves the relevant role of nutrigenomics in cancer management. By deciphering the network of nutrient-gene connections associated with cancer, relevant data will be transposed as therapeutic interventions for this devastating pathology and for fulfilling the concept of personalized nutrition. All these are presented under the nutrigenomics canopy for a better comprehension of the relation between ingested phytochemicals and chemoprevention or chemotherapy. The profits from the nutrigenomics progress, with a particular focus on the coding and noncoding genes related to the exposure of natural compounds need to be validated. A precise attention receives the evaluation of the role of natural compounds in tandem with conventional therapy using genomic approaches, with emphasis on the capacity to inhibit drug resistance mechanisms. All these relevant nutrigenomics aspects are summarized in the present review paper. It is concluded that further nutrigenomics studies are required to improve our understanding related to the complex mechanisms of action of the natural compounds and for their appropriate application as gears in cancer therapy.

Cancer Chemoprevention by Resveratrol: The p53 Tumor Suppressor Protein as a Promising Molecular Target

Increasing epidemiological and experimental evidence has demonstrated an inverse relationship between the consumption of plant foods and the incidence of chronic diseases, including cancer. Microcomponents that are naturally present in such foods, especially polyphenols, are responsible for the benefits to human health. Resveratrol is a diet-derived cancer chemopreventive agent with high therapeutic potential, as demonstrated by different authors. The aim of this review is to collect and present recent evidence from the literature regarding resveratrol and its effects on cancer prevention, molecular signaling (especially regarding the involvement of p53 protein), and therapeutic perspectives with an emphasis on clinical trial results to date.

Survivin downregulation using siRNA nanoliposomes inhibits cell proliferation and promotes the apoptosis of MHCC-97H hepatic cancer cells: An in vitro and in vivo study

At present, survivin is one of the most cancer-specific proteins that has been identified. The present study aimed to investigate the antitumor effects of novel survivin small interfering RNA (siRNA) nanoliposomes targeting survivin in human hepatocellular carcinoma MHCC-97H cells and xenograft mouse models. Survivin-targeted siRNA nanoliposomes were prepared and transfected into MHCC-97H cells and MHCC-97H-bearing nude mice. Survivin expression was analyzed using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting. Cell viability was analyzed using an MTT assay and apoptosis was evaluated using Hoechst and Annexin V-fluorescein isothiocyanate/propidium iodide staining. Tumor growth in MHCC-97H-bearing mice was monitored following treatment and tumor samples were obtained for survivin expression analysis using RT-qPCR, western blotting and immunohistochemistry staining. Survivin expression levels were significantly downregulated by nanoliposome-mediated survivin siRNA delivery and this was associated with a significant inhibition of cell growth and an increase in the apoptosis of MHCC-97H cells. Downregulation of survivin expression using survivin siRNA nanoliposomes inhibited tumor growth in the MHCC-97H xenograft models without significant treatment-associated toxicity. Therefore, a cationic nanoliposome-based survivin siRNA delivery system was constructed and demonstrated to be efficient for survivin siRNA delivery in in vitro and in vivo studies. These results demonstrate that survivin downregulation was able to significantly attenuate cell proliferation and induce the apoptosis of MHCC-97H cells, as well as inhibit tumor cell growth in MHCC-97H xenograft models, indicating that survivin suppression using siRNA may contribute to the inhibition of tumor development by suppressing cell proliferation and promoting apoptosis.

ErbB Proteins as Molecular Target of Dietary Phytochemicals in Malignant Diseases

ErbB proteins overexpression, in both normal and mutated forms, is associated with invasive forms of cancer prone to metastasis and with stronger antiapoptotic mechanisms and therefore more challenging to treat. Downstream effectors of ErbB receptors mediating these phenotypic traits include MAPK, STAT, and PI3K/AKT/mTOR pathways. Various phytochemical compounds were studied for their large number of biological effects including anticancer activity. Among these compounds, epigallocatechin-3-gallate (EGCG), the main catechin from green tea leaves, and curcumin, component of the curry powder, constituted the object of numerous studies. Both compounds were shown to act directly either on ErbB expression, or on their downstream signaling molecules. In this paper we aim to review the involvement of ErbB proteins in cancer as well as the biologic activity of EGCG and curcumin in ErbB expressing and overexpressing malignancies. The problems arising in the administration of the two compounds due to their reduced bioavailability when orally administered, as well as the progress made in this field, from using novel formulations to improved dosing regimens or improved synthetic analogs, are also discussed.

Advances in Synergistic Combinations of Chinese Herbal Medicine for the Treatment of Cancer

The complex pathology of cancer development requires correspondingly complex treatments. The traditional application of individual single-target drugs fails to sufficiently treat cancer with durable therapeutic effects and tolerable adverse events. Therefore, synergistic combinations of drugs represent a promising way to enhance efficacy, overcome toxicity and optimize safety. Chinese Herbal Medicines (CHMs) have long been used as such synergistic combinations. Therefore, we summarized the synergistic combinations of CHMs used in the treatment of cancer and their roles in chemotherapy in terms of enhancing efficacy, reducing side effects, immune modulation, as well as abrogating drug resistance. Our conclusions support the development of further science-based holistic modalities for cancer care.

Resveratrol enhances the efficacy of sorafenib mediated apoptosis in human breast cancer MCF7 cells through ROS, cell cycle inhibition, caspase 3 and PARP cleavage

Despite advances in diagnosis and treatment options, breast cancer is one of the main causes of cancer related death among women worldwide. Present study is aimed to preliminarily evaluate our hypothesis that the combination of resveratrol (RSV), a natural antioxidant, and lower dose of sorafenib (SF), a multi-kinase inhibitor and a component of ERK1/2 (extracellular signal-regulated kinase 1/2) pathway, would augment apoptosis in human breast cancer MCF7 cells. MCF7 cellexpressions s were treated with RSV, SF and their combination. MTT (3-[4,5-dimethylthiazol-2-yl] -2, 5-diphenyl-tetrazolium bromide) assay, DNA fragmentation assay, Hoechst33342, H₂DCFDA (2', 7'-Dichlorodihydrofluorescein diacetate), Rhodamine123 staining, and Western Blot to detect different signaling protein expressions, were conducted to test the hypothesis. Combination of RSV and SF showed higher cytotoxicity on MCF7 cells than their individual treatment. Results from morphology change, Hoechst33342 staining, and DNA fragmentation suggested higher apoptosis data in the combinational treatment. Intracellular ROS (reactive oxygen species) levels, p53 and Bax/Bcl2 expressions, and decrease in mitochondrial membrane potential were also higher in the combinational treatment. Up-regulation of apaf-1, cl. caspase 9, cl. caspase 3 and cl. PARP (poly (ADP-Ribose) polymerase) were also noticed, while the expressions of cyclinD1 and cyclinB1 were decreased in the combinational group. The increase in apoptosis and signaling protein expressions with RSV and SF combinational treatment were increased over time. The combination of RSV and lower dose of SF at 6μM showed enhanced apoptotic activity than SF alone. Therefore, RSV can be considered as a neo-adjuvant to improve SF efficacy in breast cancer treatment.

Curcumin and Resveratrol in the Management of Cognitive Disorders: What is the Clinical Evidence?

A growing body of in vitro and in vivo evidences shows a possible role of polyphenols in counteracting neurodegeneration: curcumin and resveratrol are attractive substances in this regard. In fact, epidemiological studies highlight a neuroprotective effect of turmeric (rhizome of Curcuma longa L.), the main source of curcumin. Moreover, the consumption of red wine, the main source of resveratrol, has been related to a lower risk of developing dementia. In this review, we analyzed the published clinical trials investigating curcumin and resveratrol in the prevention or treatment of cognitive disorders. The ongoing studies were also described, in order to give an overview of the current search on this topic. The results of published trials (five for curcumin, six for resveratrol) are disappointing and do not allow to draw conclusions about the therapeutic or neuroprotective potential of curcumin and resveratrol. These compounds, being capable of interfering with several processes implicated in the early stages of dementia, could be useful in preventing or in slowing down the pathology. To this aim, an early diagnosis using peripheral biomarkers becomes necessary. Furthermore, the potential preventive activity of curcumin and resveratrol should be evaluated in long-term exposure clinical trials, using preparations with high bioavailability and that are well standardized.

Challenges in Analyzing the Biological Effects of Resveratrol

The suggested health effects (e.g., disease prevention) of dietary bioactive compounds such as resveratrol are challenging to prove in comparison to man-made drugs developed for therapeutic purposes. Dietary bioactive compounds have multiple cellular targets and therefore have a variety of biological effects. Extrapolating the biological effects of dietary compounds from in vitro and in vivo animal experiments to humans may lead to over- or under-estimation of the effect and role of these compounds. The present paper will discuss a few of these challenges and suggest directions for future research. Questions we address include: (1) Is the combinatorial effect of resveratrol and other compounds real? (2) What are the real and relevant doses of resveratrol after administration? and (3) Is it possible to estimate the preventive effect of resveratrol by clinical trials using standard experimental designs? The examples concerning resveratrol taken from the scientific literature are mainly from 2010 and later. The challenges pointed out in this review are similar to most naturally occurring bioactive compounds.