Curcumin (diferuloylmethane) alters the expression profiles of microRNAs in human pancreatic cancer cells

Plant bioactive compounds driven microRNAs (miRNAs): A potential source and novel strategy targeting gene and cancer therapeutics

Irrespective of medical technology improvements, cancer ranks among the leading causes of mortality worldwide. Although numerous cures and treatments exist, creating alternative cancer therapies with fewer adverse side effects is vital. Since ancient times, plant bioactive compounds have already been used as a remedy to heal cancer. These plant bioactive compounds and their anticancer activity can also deregulate the microRNAs (miRNAs) in the cancerous cells. Therefore, the deregulation of miRNAs in cancer cells by plant bioactive compounds and the usage of the related miRNA could be a promising approach for cancer cure, mainly to prevent cancer and overcome chemotherapeutic side effect problems. Hence, this review highlights the function of plant bioactive compounds as an anticancer agent through the underlying mechanism that alters the miRNA expression in cancer cells, ultimately leading to apoptosis. Moreover, this review provides insight into using plant bioactive compounds -driven miRNAs as an anticancer agent to develop miRNA-based cancer gene therapy. They can be the potential resource for gene therapy and novel strategies targeting cancer therapeutics.

Exploring the therapeutic mechanism of curcumin in prostate cancer using network pharmacology and molecular docking

Objective

Curcumin, a phenolic compound extracted from turmeric rhizomes, exhibits antitumour effects in preclinical models of tumours. However, its mechanism of action in prostate cancer remains unclear. Exploring the molecular mechanisms of curcumin in prostate cancer based on network pharmacology and molecular docking provides a new theoretical basis for prostate cancer treatment.

Method

Using tools such as PharmMapper, SuperPred, TargetNet, and SwissTargetPrediction, we obtained information on curcumin-related targets. We comprehensively collected prostate cancer-related targets from several databases, including GeneCards, CTD, DisGeNET, OMIM, and PharmGKB. Cross-cutting drug-disease targets were then derived by screening using the Venny 2.1.0 tool. Subsequently, we used the DAVID platform to perform in-depth GO and KEGG enrichment analyses of the drug-disease-shared targets. To construct a PPI network map of the cross-targets and screen the 10 core targets, we combined the STRING database and Cytoscape 3.7.2. Molecular docking experiments were performed using AutoDockTools 1.5.7 software. Finally, we used several databases such as GEPIA, HPA, cBioPortal, and TIMER to further analyse the screened core targets in detail.

Result

We identified 307 key targets of curcumin in cancer treatment. After GO functional enrichment analysis, we obtained 1119 relevant entries, including 782 biological progression (BP) entries, 112 cellular component (CC) entries, and 225 molecular function (MF) entries. In addition, KEGG pathway enrichment analysis revealed 126 signalling pathways, which were mainly involved in the cancer pathway, such as lipid and atherosclerosis pathway, PI3K-Akt signal pathway, MAPK signal pathway, Ras signal pathways, and chemical carcinogenesis-reactive oxygen species. By applying Cytoscape 3.7.2 software, we identified SRC, PIK3R1, STAT3, AKT1, HSP90AA1, ESR1, EGFR, HSP90AB1, MAPK8, and MAPK1 as core targets. Molecular docking experiments showed that the binding energies of curcumin to these core targets were all below -1.85 kJ mol-1, which fully demonstrated that curcumin could spontaneously bind to these core targets. Finally, these results were validated at multiple levels, including mRNA expression, protein expression, and immune infiltration.

Conclusion

Through in-depth network pharmacology and molecular docking studies, we have found that curcumin may have anticancer potential by upregulating the expression of PIK3R1 and STAT3, and downregulating the binding ability of molecules such as SRC, AKT1, HSP90AA1, ESR1, EGFR, HSP90AB1, MAPK8, and MAPK1. In addition, curcumin may interfere with the cyclic process of prostate cancer cells by inhibiting key signalling pathways such as the PI3K-Akt signalling pathway, MAPK signalling pathway, and Ras, thereby inhibiting their growth. This study not only reveals the potential molecular mechanism of curcumin in the treatment of prostate cancer but also provides an important theoretical basis for subsequent research.

Plant-based natural products in cancer therapeutics

Various cells in our body regularly divide to replace old cells and dead cells. For a living cell to be growing, cell division and differentiation is highly essential. Cancer is characterised by uncontrollable cell division and invasion of other tissues due to dysregulation in the cell cycle. An accumulation of genetic changes or mutations develops through different physical (UV and other radiations), chemical (chewing and smoking of tobacco, chemical pollutants/mutagens), biological (viruses) and hereditary factors that can lead to cancer. Now, cancer is considered as a major death-causing factor worldwide. Due to advancements in technology, treatment like chemotherapy, radiation therapy, bone marrow transplant, immunotherapy, hormone therapy and many more in the rows. Although, it also has some side effects like fatigue, hair fall, anaemia, nausea and vomiting, constipation. Modern improved drug therapies come with severe side effects. There is need for safer, more effective, low-cost treatment with lesser side-effects. Biologically active natural products derived from plants are the emerging strategy to deal with cancer proliferation. Moreover, they possess anti-carcinogenic, anti-proliferative and anti-mutagenic properties with reduced side effects. They also detoxify and remove reactive substances formed by carcinogenic agents. In this article, we discuss different plant-based products and their mechanism of action against cancer.

Curcuminoids as Cell Signaling Pathway Modulators: A Potential Strategy for Cancer Prevention

Despite substantial advancements in curative modern medicine in the last few decades, cancer risk and casualty rates have continued to mount globally. The exact reason for cancer's onset and progression is still unknown. However, skeletal and functional abnormalities in the genetic code are assumed to be the primary cause of cancer. Many lines of evidence reported that some medicinal plants can be utilized to curb cancer cell proliferation with a safe, fruitful, and cost-efficient perspective. Curcuminoid, isolated from Curcuma longa, have gotten a lot of focus due to their anticancer potential as they reduce tumor progression, invasion, and dissemination. Further, they modulated signal transduction routes like MAPK, PI3K/Akt/mTOR, JAK/STAT, and Wnt/β-catenin, etc., and triggered apoptosis as well as actuated autophagy in malignant cells without altering the normal cells, thus preventing cancer progression. Besides, Curcuminoid also regulate the function and expression of anti-tumor and carcinogenic miRNAs. Clinical studies also reported the therapeutic effect of Curcuminoid against various cancer through decreasing specific biomarkers like TNF-α, Bcl-2, COX-2, PGE2, VEGF, IκKβ, and various cytokines like IL-12p70, IL-10, IL-2, IFN-γ levels and increasing in p53 and Bax levels. Thus, in the present review, we abridged the modulation of several signal transduction routes by Curcuminoids in various malignancies, and its modulatory role in the initiation of tumor-suppressive miRNAs and suppression of the oncogenic miRNAs are explored. Additionally, various pharmacokinetic approaches have been projected to address the Curcuminoids bioavailability like the use of piperine as an adjuvant; nanotechnology- based Curcuminoids preparations utilizing Curcuminoids analogues are also discussed.

Recent insights into the nutritional immunomodulation of cancer-related microRNAs

Cancer is the most common cause of death worldwide, following cardiovascular diseases. Cancer is a multifactorial disease and many reasons such as physical, chemical, biological, and lifestyle-related factors. Nutrition, which is one of the various factors that play a role in the prevention, development, and treatment of many types of cancer, affects the immune system, which is characterized by disproportionate pro-inflammatory signaling in cancer. Studies investigating the molecular mechanisms of this effect have shown that foods rich in bioactive compounds, such as green tea, olive oil, turmeric, and soybean play a significant role in positively changing the expression of miRNAs involved in the regulation of genes associated with oncogenic/tumor-suppressing pathways. In addition to these foods, some diet models may change the expression of specific cancer-related miRNAs in different ways. While Mediterranean diet has been associated with anticancer effects, a high-fat diet, and a methyl-restricted diet are considered to have negative effects. This review aims to discuss the effects of specific foods called "immune foods," diet models, and bioactive components on cancer by changing the expression of miRNAs in the prevention and treatment of cancer.

Natural compounds targeting nuclear receptors for effective cancer therapy

Human nuclear receptors (NRs) are a family of forty-eight transcription factors that modulate gene expression both spatially and temporally. Numerous biochemical, physiological, and pathological processes including cell survival, proliferation, differentiation, metabolism, immune modulation, development, reproduction, and aging are extensively orchestrated by different NRs. The involvement of dysregulated NRs and NR-mediated signaling pathways in driving cancer cell hallmarks has been thoroughly investigated. Targeting NRs has been one of the major focuses of drug development strategies for cancer interventions. Interestingly, rapid progress in molecular biology and drug screening reveals that the naturally occurring compounds are promising modern oncology drugs which are free of potentially inevitable repercussions that are associated with synthetic compounds. Therefore, the purpose of this review is to draw our attention to the potential therapeutic effects of various classes of natural compounds that target NRs such as phytochemicals, dietary components, venom constituents, royal jelly-derived compounds, and microbial derivatives in the establishment of novel and safe medications for cancer treatment. This review also emphasizes molecular mechanisms and signaling pathways that are leveraged to promote the anti-cancer effects of these natural compounds. We have also critically reviewed and assessed the advantages and limitations of current preclinical and clinical studies on this subject for cancer prophylaxis. This might subsequently pave the way for new paradigms in the discovery of drugs that target specific cancer types.

An Overview of the Enhanced Effects of Curcumin and Chemotherapeutic Agents in Combined Cancer Treatments

Due to the progressive ageing of the human population, the number of cancer cases is increasing. For this reason, there is an urgent need for new treatments that can prolong the lives of cancer patients or ensure them a good quality of life. Although significant progress has been made in the treatment of cancer in recent years and the survival rate of patients is increasing, limitations in the use of conventional therapies include the frequent occurrence of side effects and the development of resistance to chemotherapeutic agents. These limitations are prompting researchers to investigate whether combining natural agents with conventional drugs could have a positive therapeutic effect in cancer treatment. Several natural bioactive compounds, especially polyphenols, have been shown to be effective against cancer progression and do not exert toxic effects on healthy tissues. Many studies have investigated the possibility of combining polyphenols with conventional drugs as a novel anticancer strategy. Indeed, this combination often has synergistic benefits that increase drug efficacy and reduce adverse side effects. In this review, we provide an overview of the studies describing the synergistic effects of curcumin, a polyphenol that has been shown to have extensive cytotoxic functions against cancer cells, including combined treatment. In particular, we have described the results of recent preclinical and clinical studies exploring the pleiotropic effects of curcumin in combination with standard drugs and the potential to consider it as a promising new tool for cancer therapy.

Integrated Transcriptome and Molecular Docking to Identify the Hub Superimposed Attenuation Targets of Curcumin in Breast Cancer Cells

Numerous in vitro and in vivo studies have shown that curcumin primarily activates apoptotic pathways in cancer cells and inhibits cancer progression by modulating various molecular targets. In this study, we utilized reverse docking servers to predict 444 human proteins that may potentially be targeted by curcumin. Then, high-throughput assays were conducted by using RNA-seq technology on curcumin-treated MCF-7 (human breast cancer ER (+)) and MDA-MB-231 (human breast cancer ER(-)/TNBC) cancer cell lines. Enrichment analysis identified seven and eight significantly down-regulated signaling pathways in these two cell lines, where the enriched genes were used to construct protein-protein interaction networks. From these networks, the MCODE algorithm screened out 42 hub targets, which are core genes of the RTK-(PI3K-AKT)/(MEK/ERK1/2) crosstalk network. Genetic alteration and expression patterns of hub targets of curcumin may be closely related to the overall pathogenesis and prognosis of breast cancer. MAPKAPK3, AKT3, CDK5, IGF1R, and MAPK11 are potential prognostic markers and therapeutic targets of curcumin in patients with triple-negative breast cancer. Molecular docking and transcriptomic results confirmed that curcumin can inhibit these high-scoring targets at the protein level. Additionally, these targets can act as self-feedback factors, relying on the cascading repressive effects in the network to limit their own transcription at the mRNA level. In conclusion, the integration of transcriptomic and molecular docking approaches enables the rapid identification of dual or multiple inhibitory targets of curcumin in breast cancer. Our study provides the potential elucidation of the anti-cancer mechanism of curcumin.

Inhibition of Cancer Development by Natural Plant Polyphenols: Molecular Mechanisms

Malignant tumors remain one of the main sources of morbidity and mortality around the world. A chemotherapeutic approach to cancer treatment poses a multitude of challenges, primarily due to the low selectivity and genotoxicity of the majority of chemotherapeutic drugs currently used in the clinical practice, often leading to treatment-induced tumors formation. Highly selective antitumor drugs can largely resolve this issue, but their high selectivity leads to significant drawbacks due to the intrinsic tumor heterogeneity. In contrast, plant polyphenols can simultaneously affect many processes that are involved in the acquiring and maintaining of hallmark properties of malignant cells, and their toxic dose is typically much higher than the therapeutic one. In the present work we describe the mechanisms of the action of polyphenols on cancer cells, including their effects on genetic and epigenetic instability, tumor-promoting inflammation, and altered microbiota.

Modulation of microRNAs expression and cellular signaling pathways through curcumin as a potential therapeutical approach against ovarian cancer: A review

Short non-coding RNAs called microRNAs (miRNAs) control gene expression by either inhibiting translation or degrading messenger RNA. MiRNAs are crucial for many biological functions, and the deregulation of their expression is strongly linked to the emergence of cancer. A single miRNA controls several gene expressions, allowing it to simultaneously control a number of cellular signaling pathways. As a result, miRNAs may be used as therapeutic targets as well as biomarkers for the prognosis and diagnosis of different cancers. Recent research has shown that natural compounds like curcumin, resveratrol and quercetin exert their pro-apoptotic and/or anti-proliferative impacts by modulating one and/or more miRNAs, which inhibits the growth of cancer cells, induces apoptosis, or increases the effectiveness of conventional cancer therapies. Here, we summarize the most recent developments in curcumin's control over the expression of miRNAs and emphasize the significance of these herbal remedies as a viable strategy in the treatment and prevention of cancer.

Curcumin enhances the anti-cancer efficacy of paclitaxel in ovarian cancer by regulating the miR-9-5p/BRCA1 axis

Background: Patients with late-stage ovarian cancer still have a very poor prognosis due to chemotherapy resistance. Curcumin has been shown to synergistically enhance the therapeutic effects of multiple chemotherapeutic agents, but the potential involvement of curcumin in ovarian cancer is largely unknown. This study aimed to investigate whether curcumin has synergistic anti-cancer effects with paclitaxel in ovarian cancer and its underlying mechanism. Methods: Ovarian cancer cell lines (SKOV3 and A2780) were treated with curcumin, alone or combined with paclitaxel. Cell viability, colony formation, EdU incorporation assays, and flow cytometry were used to assess cell proliferation, apoptosis, and cell cycle progression. The cytotoxic synergistic effect of curcumin and paclitaxel was detected by Calcusyn software. RNA immunoprecipitation assay was used to verify the interaction between miR-9-5p and BRCA1. qRT-PCR and Western blot were performed to detect gene and protein expression. Results: We found that curcumin and paclitaxel synergistically inhibited proliferation and promoted apoptosis in ovarian cancer cells. Furthermore, curcumin and paclitaxel combination resulted in decreased miR-9-5p expression and increased BRCA1 expression. Functionally, miR-9-5p overexpression counteracted the synergistic effect of curcumin and paclitaxel on cell proliferation and apoptosis by targeting BRCA1. Meanwhile, in vivo experiments revealed that curcumin and paclitaxel combination dramatically suppressed the growth of transplanted tumors, while miR-9-5p mimics eliminated the growth inhibition of xenografts induced by the combined treatment. Conclusion: Curcumin enhanced the anti-cancer efficacy of paclitaxel in ovarian cancer by regulating the miR-9-5p/BRCA1 axis. These findings provide strong evidence for clinical investigation of curcumin and paclitaxel combination as a novel strategy for ovarian cancer patients, and identify miR-9-5p and BRCA1 as key targets for regulating sensitivity to this therapy.

Evidence for Multilevel Chemopreventive Activities of Natural Phenols from Functional Genomic Studies of Curcumin, Resveratrol, Genistein, Quercetin, and Luteolin

Herein, I present an updated and contextualized literature review of functional genomic studies of natural phenols in the context of cancer. I suggest multilevel chemopreventive and anticancer mechanisms of action, which are shared by multiple dietary natural phenols. Specifically, I cite evidence that curcumin and resveratrol have multilevel anti-cancer effects through: (1) inducing either p53-dependent or p53-independent apoptosis in cancer cell lines, (2) acting as potent regulators of expression of oncogenic and anti-oncogenic microRNAs, and (3) inducing complex epigenetic changes that can switch off oncogenes/switch on anti-oncogenes. There is no simple reductionist explanation for anti-cancer effects of curcumin and resveratrol. More generally, multilevel models of chemoprevention are suggested for related natural phenols and flavonoids such as genistein, quercetin, or luteolin.

Contribution of Non-Coding RNAs to Anticancer Effects of Dietary Polyphenols: Chlorogenic Acid, Curcumin, Epigallocatechin-3-Gallate, Genistein, Quercetin and Resveratrol

Growing evidence has been accumulated to show the anticancer effects of daily consumption of polyphenols. These dietary polyphenols include chlorogenic acid, curcumin, epigallocatechin-3-O-gallate, genistein, quercetin, and resveratrol. These polyphenols have similar chemical and biological properties in that they can act as antioxidants and exert the anticancer effects via cell signaling pathways involving their reactive oxygen species (ROS)-scavenging activity. These polyphenols may also act as pro-oxidants under certain conditions, especially at high concentrations. Epigenetic modifications, including dysregulation of noncoding RNAs (ncRNAs) such as microRNAs, long noncoding RNAs, and circular RNAs are now known to be involved in the anticancer effects of polyphenols. These polyphenols can modulate the expression/activity of the component molecules in ROS-scavenger-triggered anticancer pathways (RSTAPs) by increasing the expression of tumor-suppressive ncRNAs and decreasing the expression of oncogenic ncRNAs in general. Multiple ncRNAs are similarly modulated by multiple polyphenols. Many of the targets of ncRNAs affected by these polyphenols are components of RSTAPs. Therefore, ncRNA modulation may enhance the anticancer effects of polyphenols via RSTAPs in an additive or synergistic manner, although other mechanisms may be operating as well.

Modulation of the activity of histone lysine methyltransferases and demethylases by curcumin analog in leukaemia cells

Curcumin is a known epigenetic modifier that demonstrated antitumor effect in different types of cancer. The poor solubility and metabolic stability are major drawbacks that limit its development as an antitumor agent. Dimethoxycurcumin (DMC) is a more soluble and stable curcumin analog. In this study, we compared the effect of both drugs on a variety of histone posttranslational modifications and on the activity of histone lysine methyltransferase (HKMTs) and demethylase (HKDMTs) enzymes that target the H3K4, H3K9 and H3K27 epigenetic marks. Mass spectrometry was used to quantitate the changes in 95 histone posttranslational modifications induced by curcumin or DMC. The effect of both drugs on the enzymatic activity of HKMTs and HKDMs was measured using an antibody‐based assay. Mass spectrometry analysis showed that curcumin and DMC modulated several histone modifications. Histone changes were not limited to lysine methylation and acetylation but included arginine and glutamine methylation. Only few histone modifications were similarly changed by both drugs. On the contrary, the effect of both drugs on the activity of HKMTs and HKDMs was very similar. Curcumin and DMC inhibited the HKMTs enzymes that target the H3K4, H3K9 and H3K27 marks and increased the activity of the HKDMs enzymes LSD1, JARID and JMJD2. In conclusion, we identified novel enzymatic targets for both curcumin and DMC that support their use and development as epigenetic modifiers in cancer treatment. The multiple targets modulated by both drugs could provide a therapeutic advantage by overcoming drug resistance development.

Curcumin Sensitises Cancerous Kidney Cells to TRAIL Induced Apoptosis via Let-7C Mediated Deregulation of Cell Cycle Proteins and Cellular Metabolism

Targeted therapies are the most attractive options in the treatment of different tumours, including kidney cancers. Such therapies have entered a golden era due to advancements in research, breakthroughs in scientific knowledge, and a better understanding of cancer therapy mechanisms, which significantly improve the survival rates and life expectancy of patients. The use of tumour necrosis factor (TNF)-related apoptosis inducing ligand (TRAIL) as an anticancer therapy has attracted the attention of the scientific community and created great excitement due to its selectivity in targeting cancerous cells with no toxic impacts on normal tissues. However, clinical studies disappointingly showed the emergence of resistance against TRAIL. This study aimed to employ curcumin to sensitise TRAIL-resistant kidney cancerous ACHN cells, as well as to gain insight into the molecular mechanisms of TRAIL sensitization. Curcumin deregulated the expression of apoptosis-regulating micro Ribonucleic Acid (miRNAs), most notably, let-7C. Transfecting ACHN cells with a let-7C antagomir significantly increased the expression of several cell cycle protein, namely beta (β)-catenin, cyclin dependent kinase (CDK)1/2/4/6 and cyclin B/D. Further, it overexpressed the expression of the two key glycolysis regulating proteins including hypoxia-inducible factor 1-alpha (HIF-1α) and pyruvate dehydrogenase kinase 1 (PDK1). Curcumin also suppressed the expression of the overexpressed proteins when added to the antagomir transfected cells. Overall, curcumin targeted ACHN cell cycle and cellular metabolism by promoting the differential expression of let-7C. To the best of our knowledge, this is the first study to mechanistically report the cancer chemosensitisation potential of curcumin in kidney cancer cells via induction of let-7C.

Acetylation-Specific Interference by Anti-Histone H3K9ac Intrabody Results in Precise Modulation of Gene Expression

Among Histone post-translational modifications (PTMs), lysine acetylation plays a pivotal role in the epigenetic regulation of gene expression, mediated by chromatin modifying enzymes. Due to their activity in physiology and pathology, several chemical compounds have been developed to inhibit the function of these proteins. However, the pleiotropy of these classes of proteins represents a weakness of epigenetic drugs. Ideally, a new generation of epigenetic drugs should target with molecular precision individual acetylated lysines on the target protein. We exploit a PTM-directed interference, based on an intrabody (scFv-58F) that selectively binds acetylated lysine 9 of histone H3 (H3K9ac), to test the hypothesis that targeting H3K9ac yields more specific effects than inhibiting the corresponding HAT enzyme that installs that PTM. In yeast scFv-58F modulates, gene expression in a more specific way, compared to two well-established HAT inhibitors. This PTM-specific interference modulated expression of genes involved in ribosome biogenesis and function. In mammalian cells, the scFv-58F induces exclusive changes in the H3K9ac-dependent expression of specific genes. These results suggest the H3K9ac-specific intrabody as the founder of a new class of molecules to directly target histone PTMs, inverting the paradigm from inhibiting the writer enzyme to acting on the PTM.

Anti-Cancer Effects of Dietary Polyphenols via ROS-Mediated Pathway with Their Modulation of MicroRNAs

Consumption of coffee, tea, wine, curry, and soybeans has been linked to a lower risk of cancer in epidemiological studies. Several cell-based and animal studies have shown that dietary polyphenols like chlorogenic acid, curcumin, epigallocatechin-3-O-gallate, genistein, quercetin and resveratrol play a major role in these anticancer effects. Several mechanisms have been proposed to explain the anticancer effects of polyphenols. Depending on the cellular microenvironment, these polyphenols can exert double-faced actions as either an antioxidant or a prooxidant, and one of the representative anticancer mechanisms is a reactive oxygen species (ROS)-mediated mechanism. These polyphenols can also influence microRNA (miR) expression. In general, they can modulate the expression/activity of the constituent molecules in ROS-mediated anticancer pathways by increasing the expression of tumor-suppressive miRs and decreasing the expression of oncogenic miRs. Thus, miR modulation may enhance the anticancer effects of polyphenols through the ROS-mediated pathways in an additive or synergistic manner. More precise human clinical studies on the effects of dietary polyphenols on miR expression will provide convincing evidence of the preventive roles of dietary polyphenols in cancer and other diseases.

Molecular Mechanism of Curcumin and Its Analogs as Multifunctional Compounds against Pancreatic Cancer

Pancreatic cancer (PC) is one of the most common malignant tumors with a poor prognosis and high mortality. Surgical resection is the most effective treatment for PC; however, only a minority of patients have resectable tumors. Chemotherapy is the primary treatment for PC. Curcumin is a natural chemical substance obtained from plants with a wide range of pharmacological activities. Research evidence suggests that curcumin can influence PC development through multiple molecular mechanisms. The synthesis of novel curcumin analogs and preparation of curcumin nano-formulations are effective strategies to overcome the low bioavailability of curcumin in the treatment of PC. This review aims to summarize the mechanisms of action of curcumin in preclinical and clinical studies on PC and research progress in enhancing its bioavailability.

Involvement of microRNA modifications in anticancer effects of major polyphenols from green tea, coffee, wine, and curry

Epidemiological studies have shown that consumption of green tea, coffee, wine, and curry may contribute to a reduced risk of various cancers. However, there are some cancer site-specific differences in their effects; for example, the consumption of tea or wine may reduce bladder cancer risk, whereas coffee consumption may increase the risk. Animal and cell-based experiments have been used to elucidate the anticancer mechanisms of these compounds, with reactive oxygen species (ROS)-based mechanisms emerging as likely candidates. Chlorogenic acid (CGA), curcumin (CUR), epigallocatechin gallate (EGCG), and resveratrol (RSV) can act as antioxidants that activate AMP-activated protein kinase (AMPK) to downregulate ROS, and as prooxidants to generate ROS, leading to the downregulation of NF-κB. Polyphenols can modulate miRNA (miR) expression, with these dietary polyphenols shown to downregulate tumor-promoting miR-21. CUR, EGCG, and RSV can upregulate tumor-suppressing miR-16, 34a, 145, and 200c, but downregulate tumor-promoting miR-25a. CGA, EGCG, and RSV downregulate tumor-suppressing miR-20a, 93, and 106b. The effects of miRs may combine with ROS-mediated pathways, enhancing the anticancer effects of these polyphenols. More precise analysis is needed to determine how the different modulations of miRs by polyphenols relate to the cancer site-specific differences found in epidemiological studies related to the consumption of foods containing these polyphenols.

The Role of Epigenetic Modifications in Human Cancers and the Use of Natural Compounds as Epidrugs: Mechanistic Pathways and Pharmacodynamic Actions

Cancer is a complex disease resulting from the genetic and epigenetic disruption of normal cells. The mechanistic understanding of the pathways involved in tumor transformation has implicated a priori predominance of epigenetic perturbations and a posteriori genetic instability. In this work, we aimed to explain the mechanistic involvement of epigenetic pathways in the cancer process, as well as the abilities of natural bioactive compounds isolated from medicinal plants (flavonoids, phenolic acids, stilbenes, and ketones) to specifically target the epigenome of tumor cells. The molecular events leading to transformation, angiogenesis, and dissemination are often complex, stochastic, and take turns. On the other hand, the decisive advances in genomics, epigenomics, transcriptomics, and proteomics have allowed, in recent years, for the mechanistic decryption of the molecular pathways of the cancerization process. This could explain the possibility of specifically targeting this or that mechanism leading to cancerization. With the plasticity and flexibility of epigenetic modifications, some studies have started the pharmacological screening of natural substances against different epigenetic pathways (DNA methylation, histone acetylation, histone methylation, and chromatin remodeling) to restore the cellular memory lost during tumor transformation. These substances can inhibit DNMTs, modify chromatin remodeling, and adjust histone modifications in favor of pre-established cell identity by the differentiation program. Epidrugs are molecules that target the epigenome program and can therefore restore cell memory in cancerous diseases. Natural products isolated from medicinal plants such as flavonoids and phenolic acids have shown their ability to exhibit several actions on epigenetic modifiers, such as the inhibition of DNMT, HMT, and HAT. The mechanisms of these substances are specific and pleiotropic and can sometimes be stochastic, and their use as anticancer epidrugs is currently a remarkable avenue in the fight against human cancers.

Comprehensive miRNA and DNA Microarray Analyses Reveal the Response of Hepatic miR-203 and Its Target Gene to Protein Malnutrition in Rats

Adequate protein nutrition is essential for good health. Effects of protein malnutrition in animals have been widely studied at the mRNA level with the development of DNA microarray technology. Although microRNAs (miRNAs) have attracted attention for their function in regulating gene expression and have been studied in several disciplines, fewer studies have clarified the effects of protein malnutrition on miRNA alterations. The present study aimed to elucidate the relationship between protein malnutrition and miRNAs. Six-week old Wistar male rats were fed a control diet (20% casein) or a low-protein diet (5% casein) for two weeks, and their livers were subjected to both DNA microarray and miRNA array analysis. miR-203 was downregulated and its putative target Hadhb (hydroxyacyl-CoA dehydrogenase β subunit), known to regulate β-oxidation of fatty acids, was upregulated by the low-protein diet. In an in vitro experiment, miR-203 or its inhibitor were transfected in HepG2 cells, and the pattern of Hadhb expression was opposite to that of miR-203 expression. In addition, to clarifying the hepatic miRNA profile in response to protein malnutrition, these results showed that a low-protein diet increased Hadhb expression through downregulation of miR-203 and induced β-oxidation of fatty acids.

Echinacoside Suppresses the Progression of Breast Cancer by Downregulating the Expression of miR-4306 and miR-4508

The main treatment of breast cancer includes surgical resection, radiotherapy, chemotherapy, endocrine therapy, and molecular targeted therapy, but the outcomes remain unsatisfactory. Previous studies demonstrated that echinacoside, microRNA (miRNA/miR)-4306 and miR-4508 were associated with lymph node metastasis, chemoresistance and self-renewal capability in breast cancer, but in-depth studies on the underlying mechanism of their anticancer effects have not been performed to date. In order to identify the role of miR-4306 and miR-4508, and the mechanism of the antitumor effect of echinacoside in breast cancer, the present study first examined the expression of miR-4306 and miR-4508 in breast cancer tissues to examine their possible role in the development of breast cancer, then evaluated the effect of echinacoside on the expression of miR-4306 and miR-4508 on the viability, apoptosis, cell cycle, migration, and invasion abilities of breast cancer cells to explore the anti-cancer effect of echinacoside and the involvement of miR-4306 and miR-4508. Finally, the breast cancer cells and mice bearing breast cancer xenografts were treated with echinacoside and inhibitors of miR-4508 or miR-4306 to confirm their role on the anticancer effect of echinacoside. The results showed that miR-4306 and miR-4508 were decreased in breast cancer tissues and cells. Echinacoside inhibited cell proliferation, invasion and migration, and promoted the apoptosis of breast cancer cells by downregulating the expression of miR-4306 and miR-4508. In conclusion, this is the first study to show the association between echinacoside and miRNAs in cancer. The present study elucidates an underlying molecular mechanism of the antitumor effect of echinacoside on breast cancer, and thus may contribute to preventive and therapeutic strategies for breast cancer.

The role of vulpinic acid as a natural compound in the regulation of breast cancer-associated miRNAs

Background

Breast cancer is the most frequently diagnosed cancer, and no effective treatment solution has yet been found. The number of studies based on the research of novel natural compounds in the treatment of breast cancer has been increasing in recent years. The anticancer properties of natural compounds are related to the regulation of microRNA (miRNA) expression. Therefore, changing the profile of miRNAs with the use of natural products is very important in cancer treatment. However, the role of vulpinic acid and related miRNAs in breast cancer progression remains unknown. Vulpinic acid, methyl (as2E)-2-(3-hydroxy-5-oxo-4-phenylfuran-2-ylidene)-2 phenylacetate, is a natural product extracted from the lichen species and shows an anticancer effect on different cancer cells.

Methods

This study examines the effects of vulpinic acid on the miRNA levels of breast cancer (MCF-7) cells and its relationship with cell proliferation and apoptosis levels. The antiproliferative effect of vulpinic acid was screened against MCF-7 breast cancer cells and MCF-12A breast epithelial cells using the xCELLigence real-time cell analysis system. We analyzed the altered miRNA expression profile in MCF-7 breast cancer cells versus MCF-12A cells following their response to vulpinic acid through microarray analysis. The microarray analysis results were confirmed through quantitative real-time PCR and bioinformatics analysis.

Results

The results of the miRNA array and bioinformatic analyses demonstrated that 12 miRNAs were specifically responsive to vulpinic acid in MCF-7 breast cancer cells. This is the first study to reveal that vulpinic acid inhibits the expression of 12 miRNAs and suppresses breast cancer cell proliferation. The study also revealed that vulpinic acid may downregulate the expression of 12 miRNAs by repressing the FOXO-3 gene. The miRNA targets were mainly found to play a role in the apoptosis, cell cycle and MAPK pathways. Moreover, Bcl-2, Bax, procaspase-3 and procaspase-9 protein levels were assessed by western blot analysis for validation of apoptosis at the protein level.

Conclusion

This study revealed the molecular mechanisms of vulpinic acid on breast cancer and showed that vulpinic acid regulates apoptosis signaling pathways by decreasing the expression of miRNAs. The miRNA expression patterns illuminate the underlying effect of vulpinic acid in breast cancer treatment.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s40659-021-00360-4.

The Role of microRNA in Pancreatic Cancer

MicroRNAs (miRNAs) are small ribonucleic acid molecules that play a key role in regulating gene expression. The increasing number of studies undertaken on the functioning of microRNAs in the tumor formation clearly indicates their important potential in oncological therapy. Pancreatic cancer is one of the deadliest cancers. The expression of miRNAs released into the bloodstream appears to be a good indicator of progression and evaluation of the aggressiveness of pancreatic cancer, as indicated by studies. The work reviewed the latest literature on the importance of miRNAs for pancreatic cancer development.

Biological Role and Clinical Implications of microRNAs in BRCA Mutation Carriers

Women with pathogenic germline mutations in BRCA1 and BRCA2 genes have an increased risk to develop breast and ovarian cancer. There is, however, a high interpersonal variability in the modality and timing of tumor onset in those subjects, thus suggesting a potential role of other individual’s genetic, epigenetic, and environmental risk factors in modulating the penetrance of BRCA mutations. MicroRNAs (miRNAs) are small noncoding RNAs that can modulate the expression of several genes involved in cancer initiation and progression. MiRNAs are dysregulated at all stages of breast cancer and although they are accessible and evaluable, a standardized method for miRNA assessment is needed to ensure comparable data analysis and accuracy of results. The aim of this review was to highlight the role of miRNAs as potential biological markers for BRCA mutation carriers. In particular, biological and clinical implications of a link between lifestyle and nutritional modifiable factors, miRNA expression and germline BRCA1 and BRCA2 mutations are discussed with the knowledge of the best available scientific evidence.

Current clinical developments in curcumin-based therapeutics for cancer and chronic diseases

The last decade has seen an unprecedented rise in the prevalence of chronic diseases worldwide. Different mono-targeted approaches have been devised to treat these multigenic diseases, still most of them suffer from limited success due to the off-target debilitating side effects and their inability to target multiple pathways. Hence a safe, efficacious, and multi-targeted approach is the need for the hour to circumvent these challenging chronic diseases. Curcumin, a natural compound extracted from the rhizomes of Curcuma longa, has been under intense scrutiny for its wide medicinal and biological properties. Curcumin is known to manifest antibacterial, antiinflammatory, antioxidant, antifungal, antineoplastic, antifungal, and proapoptotic effects. A plethora of literature has already established the immense promise of curcuminoids in the treatment and clinical management of various chronic diseases like cancer, cardiovascular, metabolic, neurological, inflammatory, and infectious diseases. To date, more than 230 clinical trials have opened investigations to understand the pharmacological aspects of curcumin in human systems. Still, further randomized clinical studies in different ethnic populations warrant its transition to a marketed drug. This review summarizes the results from different clinical trials of curcumin-based therapeutics in the prevention and treatment of various chronic diseases.

Polyphenols as adjunctive treatments in psychiatric and neurodegenerative disorders: Efficacy, mechanisms of action, and factors influencing inter-individual response

The pathophysiology of psychiatric and neurodegenerative disorders is complex and multifactorial. Polyphenols possess a range of potentially beneficial mechanisms of action that relate to the implicated pathways in psychiatric and neurodegenerative disorders. The aim of this review is to highlight the emerging clinical trial and preclinical efficacy data regarding the role of polyphenols in mental and brain health, elucidate novel mechanisms of action including the gut microbiome and gene expression, and discuss the factors that may be responsible for the mixed clinical results; namely, the role of interindividual differences in treatment response and the potentially pro-oxidant effects of some polyphenols. Further clarification as part of larger, well conducted randomized controlled trials that incorporate precision medicine methods are required to inform clinical efficacy and optimal dosing regimens.

Another look at dietary polyphenols: challenges in cancer prevention and treatment

Cancer is a pathology that impacts in a profound manner people all over the world. The election strategy against cancer often uses chemotherapy and radiotherapy, which more often than not can present many side effects and not always reliable efficacy. By contrast, it is widely known that a diet rich in fruit and vegetables has a protective effect against cancer insurgence and development. Polyphenols are generally believed to be responsible for those beneficial actions, at least partially. In this review, we highlight the metabolic interaction between polyphenols and our metabolism and discuss their potential for anticancer prevention and therapy.

Quercetin and Luteolin Improve the Anticancer Effects of 5-Fluorouracil in Human Colorectal Adenocarcinoma In Vitro Model: A Mechanistic Insight

The aim of this study was to investigate the antitumor effects of quercetin and luteolin combined with 5-Fluorouracil (5-FU) in HT-29 human colorectal cancer cells. Cell viability induced by quercetin, luteolin and combination of these compounds with 5-FU were determined by MTT assay, also Cell death detection Elisa assay and fluorescence microscopy were performed to investigate apoptotic effects. Hu-VEGF Elisa assay was employed to determine the effects of treatments on angiogenesis. Western blot and qRT-PCR analysis were performed to investigate effects on p53, Bax, Bcl-2, p38 MAPK, mTOR, PTEN, and Akt proteins and genes. The results indicated that quercetin, luteolin and combinations of these compounds with 5-FU inhibited the growth of HT 29 cells. Compared to the control, apoptosis were triggered 8.1 and 10.1 fold in HT-29 cells, that treated with quercetin + 5-FU and luteolin + 5-FU, respectively. VEGF amount significantly decreased by combined treatments. qRT-PCR and western blot results demonstrated that quercetin, luteolin and the combinations of these flavonoids with 5-FU, modulate the apoptotic pathways in HT-29 cells. The increase in p53, Bax, p38 MAPK, and PTEN gene expression levels compared to the control group was 1.71, 1.42, 3.26, and 3.29-fold with 5-FU + L treatment, respectively, while this increase was 8.43, 1.65, 3.55, and 3.54-fold with 5-FU + Q treatment, respectively. In addition, when the anti-apoptotic Bcl-2, mTOR, and Akt gene expression levels were normalized as 1 in the control group, they were 0.28, 0.41, and 0.22 with 5-FU + L treatment, and 0.32, 0.46, and 0.39, respectively, with 5-FU + Q treatment. These findings suggested that quercetin and luteolin synergistically enhanced the anticancer effect of 5-FU in HT 29 cells and may therefore minimize the toxic effects of 5-FU in the clinical treatment of colorectal cancer.

Molecular mechanisms underlying curcumin-mediated microRNA regulation in carcinogenesis; Focused on gastrointestinal cancers

Curcumin is a bioactive ingredient found in the Rhizomes of Curcuma longa. Curcumin is well known for its chemopreventive and anti-cancer properties. Recent findings have demonstrated several pharmacological and biological impacts of curcumin, related to the control and the management of gastrointestinal cancers. Mechanistically, curcumin exerts its biological impacts via antioxidant and anti-inflammatory effects through the interaction with various transcription factors and signaling molecules. Moreover, epigenetic modulators such as microRNAs (miRNAs) have been revealed as novel targets of curcumin. Curcumin was discovered to regulate the expression of numerous pathogenic miRNAs in gastric, colorectal, esophageal and liver cancers. The present systematic review was performed to identify miRNAs that are modulated by curcumin in gastrointestinal cancers.

Therapeutic effect of curcumin in gastrointestinal cancers: A comprehensive review

Gastrointestinal (GI) cancers with a high global prevalence are a leading cause of morbidity and mortality. Accordingly, there is a great need to develop efficient therapeutic approaches. Curcumin, a naturally occurring agent, is a promising compound with documented safety and anticancer activities. Recent studies have demonstrated the activity of curcumin in the prevention and treatment of different cancers. According to systematic studies on curcumin use in various diseases, it can be particularly effective in GI cancers because of its high bioavailability in the gastrointestinal tract. Nevertheless, the clinical applications of curcumin are largely limited because of its low solubility and low chemical stability in water. These limitations may be addressed by the use of relevant analogues or novel delivery systems. Herein, we summarize the pharmacological effects of curcumin against GI cancers. Moreover, we highlight the application of curcumin's analogues and novel delivery systems in the treatment of GI cancers.

Targeting Cancer using Curcumin Encapsulated Vesicular Drug Delivery Systems

Curcumin is a major curcuminoid present in turmeric. The compound is attributed to various therapeutic properties, which include anti-oxidant, anti-inflammatory, anti-bacterial, anti-malarial, and neuroprotection. Due to its therapeutic potential, curcumin has been employed for centuries in treating different ailments. Curcumin has been investigated lately as a novel therapeutic agent in the treatment of cancer. However, the mechanisms by which curcumin exerts its cytotoxic effects on malignant cells are still not fully understood. One of the main limiting factors in the clinical use of curcumin is its poor bioavailability and rapid elimination. Advancements in drug delivery systems such as nanoparticle-based vesicular drug delivery platforms have improved several parameters, namely, drug bioavailability, solubility, stability, and controlled release properties. The use of curcumin-encapsulated niosomes to improve the physical and pharmacokinetic properties of curcumin is one such approach. This review provides an up-to-date summary of nanoparticle-based vesicular drug carriers and their therapeutic applications. Specifically, we focus on niosomes as novel drug delivery formulations and their potential in improving the delivery of challenging small molecules, including curcumin. Overall, the applications of such carriers will provide a new direction for novel pharmaceutical drug delivery, as well as for biotechnology, nutraceutical, and functional food industries.

Design of New Improved Curcumin Derivatives to Multi-targets of Cancer and Inflammation

BACKGROUND

Curcumin is a major active principle of Curcuma longa. There are more than 1700 citations in the Medline, reflecting various biological effects of curcumin. Most of these biological activities are associated with the antioxidant, anti-inflammatory and antitumor activity of the molecule. Several reports suggest various targets of natural curcumin that include growth factors, growth factor receptor, cytokines, enzymes and gene regulators of apoptosis. This review focuses on the improved curcumin derivatives that target the cancer and inflammation.

METHODOLOGY

In this present review, we explored the anticancer drugs with curcumin-based drugs under pre-clinical and clinical studies with critical examination. Based on the strong scientific reports of patentable and non-patented literature survey, we have investigated the mode of the interactions of curcumin-based molecules with the target molecules.

RESULTS

Advanced studies have added new dimensions of the molecular response of cancer cells to curcumin at the genomic level. However, poor bioavailability of the molecule seems to be the major limitation of the curcumin. Several researchers have been involved to improve the curcumin derivatives to overcome this limitation. Sufficient data of clinical trials to various cancers that include multiple myeloma, pancreatic cancer and colon cancer, have also been discussed.

CONCLUSION

The detailed analysis of the structure-activity relationship (SAR) and common synthesis of curcumin-based derivatives have been discussed in the review. Utilising the predictions of in silico coupled with validation reports of in vitro and in vivo studies have concluded many targets for curcumin. Among them, cancer-related inflammation genes regulating curcumin-based molecules are a very promising target to overcome hurdles in the multimodality therapy of cancer.

Potential Role of Curcumin and Its Nanoformulations to Treat Various Types of Cancers

Cancer is a major burden of disease globally. Each year, tens of millions of people are diagnosed with cancer worldwide, and more than half of the patients eventually die from it. Significant advances have been noticed in cancer treatment, but the mortality and incidence rates of cancers are still high. Thus, there is a growing research interest in developing more effective and less toxic cancer treatment approaches. Curcumin (CUR), the major active component of turmeric (Curcuma longa L.), has gained great research interest as an antioxidant, anticancer, and anti-inflammatory agent. This natural compound shows its anticancer effect through several pathways including interfering with multiple cellular mechanisms and inhibiting/inducing the generation of multiple cytokines, enzymes, or growth factors including IκB kinase β (IκKβ), tumor necrosis factor-alpha (TNF-α), signal transducer, and activator of transcription 3 (STAT3), cyclooxygenase II (COX-2), protein kinase D1 (PKD1), nuclear factor-kappa B (NF-κB), epidermal growth factor, and mitogen-activated protein kinase (MAPK). Interestingly, the anticancer activity of CUR has been limited primarily due to its poor water solubility, which can lead to low chemical stability, low oral bioavailability, and low cellular uptake. Delivering drugs at a controlled rate, slow delivery, and targeted delivery are other very attractive methods and have been pursued vigorously. Multiple CUR nanoformulations have also been developed so far to ameliorate solubility and bioavailability of CUR and to provide protection to CUR against hydrolysis inactivation. In this review, we have summarized the anticancer activity of CUR against several cancers, for example, gastrointestinal, head and neck, brain, pancreatic, colorectal, breast, and prostate cancers. In addition, we have also focused on the findings obtained from multiple experimental and clinical studies regarding the anticancer effect of CUR in animal models, human subjects, and cancer cell lines.

Curcumin Encapsulated in Crosslinked Cyclodextrin Nanoparticles Enables Immediate Inhibition of Cell Growth and Efficient Killing of Cancer Cells

The efficiency of anti-cancer drugs is commonly determined by endpoint assays after extended incubation times, often after days. Here we demonstrate that curcumin encapsulated in crosslinked cyclodextrin nanoparticles (CD-NP) acts extremely rapidly on cell metabolism resulting in an immediate and complete inhibition of cell growth and in efficient cancer-cell killing only few hours after incubation. This early onset of anti-cancer action was discovered by live-cell high-throughput fluorescence microscopy using an environmental stage. To date, only very few examples of covalently crosslinked nanoscale CD-based (CD-NP) drug carriers exist. Crosslinking cyclodextrins enables the adsorption of unusually high payloads of hydrophobic curcumin (762 µg CC/mg CD-NP) reflecting a molar ratio of 2.3:1 curcumin to cyclodextrin. We have investigated the effect of CD-NP encapsulated curcumin (CD-CC-NP) in comparison to free, DMSO-derived curcumin nanoparticles (CC-NP) on 4 different cell lines. Very short incubations times as low as 1 h were applied and cell responses after medium change were subsequently followed over two days. We show that cell proliferation is inhibited nearly immediately in all cell lines and that a cell- and concentration dependent cancer-cell killing occurs. Anti-cancer effects were similar with free and encapsulated curcumin, however, encapsulation in CD-NP drastically extends the long-term photostability and anti-cancer activity of curcumin. Curcumin-sensitivity is highest in HeLa cells reaching up to 90% cell death under these conditions. Sensitivity decreased from HeLa to T24 to MDA MB-231 cells. Strikingly, the immortalized non-cancerous cell line MCF-10A was robust against curcumin concentrations that were highly toxic to the other cell lines. Our results underline the potential of curcumin as gentle and yet effective natural anti-cancer agent when delivered solvent-free in stabilizing and biocompatible drug carriers such as CD-NP that enable efficient cellular delivery.

Molecular targets for the management of cancer using Curcuma longa Linn. phytoconstituents: A Review

Medicinal plants are being used for therapeutic purposes since the dawn of human civilization. The therapeutic efficacy of medicinal plants is due to the presence of wide range phytochemical constituents or secondary metabolites. The medicinal plants are traditionally used for several types of ailments. Even in those pathological conditions where other methods of treatment fail to work. Curcuma longa Linn is very common ingredient used as spice in foods as preservative and coloring material in different part of the world. It has been used as a home remedy for a variety of diseases. Curcuma longa and its isolated constituent curcumin are widely evaluated for anticancer activity. Curcumin possesses broad remedial potential due to its multi-targeting effect against many different carcinoma including leukemia, genitourinary cancers, gastrointestinal cancers and breast cancer etc. Hence, Curcumin has potential for the development of new medicine for the treatment of several diseases.

Targeting androgen receptor signaling with MicroRNAs and Curcumin: a promising therapeutic approach for Prostate Cancer Prevention and intervention

Prostate cancer (PC) is a multifactorial disease characterized by the abrogation of androgen receptor signaling. Advancement in microbiology techniques has highlighted the significant role of microRNAs (miRNAs) in the progression of PC cells from an androgen-dependent to an androgen-independent state. At that stage, prostate tumors also fail to respond to currently practiced hormone therapies. So, studies in recent decades are focused on investigating the anti-tumor effects of natural compounds in PC. Curcumin is widely recognized and now of huge prestige for its anti-proliferative abilities in different types of cancer. However, its limited solubility, compatibility, and instability in the aqueous phase are major hurdles when administering. Nanoformulations have proven to be an excellent drug delivery system for various drugs and can be used as potential delivery platforms for curcumin in PC. In this review, a shed light is given on the miRNAs-mediated regulation of androgen receptor (AR) signaling and miRNA-curcumin interplay in PC, as well as on curcumin-based nanoformulations that can be used as possible therapeutic solutions for PC.

Updated review on green tea polyphenol epigallocatechin-3-gallate as a cancer epigenetic regulator

In-depth insights in cancer biology over the past decades have highlighted the important roles of epigenetic mechanisms in the initiation and progression of tumorigenesis. The cancer epigenome usually experiences multiple alternations, including genome-wide DNA hypomethylation and site-specific DNA hypermethylation, various histone posttranslational modifications, and dysregulation of non-coding RNAs (ncRNAs). These epigenetic changes are plastic and reversible, and could potentially occur in the early stage of carcinogenesis preceding genetic mutation, offering unique opportunities for intervention therapies. Therefore, targeting the cancer epigenome or cancer epigenetic dysregulation with some selected agents (called epi-drugs) represents an evolving and promising strategy for cancer chemoprevention and therapy. Phytochemicals, as a class of pleiotropic molecules, have manifested great potential in modulating different cancer processes through epigenetic machinery, of which green tea polyphenol epigallocatechin-3-gallate (EGCG) is one of the most extensively studied. In this review, we first summarize epigenetic events involved in the pathogenesis of cancer, including DNA/RNA methylations, histone modifications and ncRNAs' dysregulations. We then focus on the recently discovered roles of phytochemicals, with a special emphasis on EGCG, in modulating different cancer processes through regulating epigenetic machinery. We finally discuss limitations of EGCG as an epigenetic modulator for cancer chemoprevention and treatment and offer potential strategies to overcome the shortcomings.

Curcumin rescue p53Y220C in BxPC-3 pancreatic adenocarcinomas cell line: Evidence-based on computational, biophysical, and in vivo studies

BACKGROUND

The p53, tumor suppressor protein is inactivated upon mutation in the DNA-binding domain and the non-functional protein leads to cancers. The p53Y220C is one of the most frequently observed mutations in p53 with a scope of rescuing the protein function using small molecules.

METHODS

Using computational modeling, biophysical, and experimental cell-based studies we tried to understand the molecular basis of Curcumin as a potential small molecule to stabilize p53Y220C mutant and restore its function. The pancreatic adenocarcinomas BxPC-3 p53Y220C mutant cell line was used for cell-based assays to determine the therapeutic potential of Curcumin to restore mutant p53 to function like wild type.

RESULTS

Our results showed that the Curcumin binds p53Y220C with K_d = 3.169 ± 0.257 μM and it increases the DNA binding affinity of the mutant by 4-fold with K_d = 851.29 ± 186.27 nM. By Fluorescence, CD, and IR spectroscopy, we could characterize the secondary structural changes and stabilization of the p53Y220C DNA binding domain upon Curcumin binding. By caspase-3 and Annexin V assays, we could demonstrate that Curcumin at 3 μM to 8 μM concentration could initiate p53 mediated apoptosis in BxPC-3 cell line. Based on our experimental studies, we propose a mechanism for the activation of ATM/Chk1 kinases pathways for apoptosis and/or G2/M cell cycle arrest in the BxPC-3 cell line mediated by functionally restored p53Y220C.

CONCLUSION

The study indicated that the natural compound Curcumin could rescue mutant p53Y220C in BxPC-3 pancreatic adenocarcinomas cell line to function like wild-type and activate apoptotic pathways.

Nutritional implications of ginger: chemistry, biological activities and signaling pathways

Ginger (Zingiber officinale Roscoe) has been used as a food, spice, supplement and flavoring agent and in traditional medicines due to its beneficial characteristics such as pungency, aroma, nutrients and pharmacological activity. Ginger and ginger extracts were reported to have numerous effects, such as those on diabetes and metabolic syndrome, cholesterol levels and lipid metabolism, and inflammation, revealed by epidemiological studies. To understand the beneficial characteristics of ginger, especially its physiological and pharmacological activities at the molecular level, the biological effects of ginger constituents, such as monoterpenes (cineole, citral, limonene and α/β-pinenes), sesquiterpenes (β-elemene, farnesene and zerumbone), phenolics (gingerols, [6]-shogaol, [6]-paradol and zingerone) and diarylheptanoids (curcumin), and the associated signaling pathways are summarized. Ginger constituents are involved in biological activities, such as apoptosis, cell cycle/DNA damage, chromatin/epigenetic regulation, cytoskeletal regulation and adhesion, immunology and inflammation, and neuroscience, and exert their effects through specific signaling pathways associated with cell functions/mechanisms such as autophagy, cellular metabolism, mitogen-activated protein kinase and other signaling, and development/differentiation. Estrogens, such as phytoestrogens, are one of the most important bioactive materials in nature, and the molecular mechanisms of estrogen actions and the assays to detect them have been discussed. The molecular mechanisms of estrogen actions induced by ginger constituents and related applications, such as the chemoprevention of cancers, and the improvement of menopausal syndromes, osteoporosis, endometriosis, prostatic hyperplasia, polycystic ovary syndrome and Alzheimer's disease, were summarized by a comprehensive search of references to understand more about their health benefits and associated health risks.

Curcumin inhibits proliferation, migration and neointimal formation of vascular smooth muscle via activating miR-22

Context: Curcumin has antitumor, antioxidative, anti-inflammatory, and anti-proliferative properties.Objective: To investigate the role of miR-22 during curcumin-induced changes in vascular smooth muscle cells (VSMC) and neointima formation in balloon-injured rat abdominal aorta.Materials and methods: Sprague-Dawley rats were randomised to the sham-operated (n = 10), operated control (injured, n = 10), and curcumin treatment (n = 10) groups. miR-22 expression was determined by real-time PCR. SP1 was assessed by western blot and real-time PCR. Rat aortic smooth muscle A7r5 cells were used to determine VSMC proliferation and migration, which were measured by the MTS, EdU staining, Transwell, and wound healing assays.Results: miR-22 levels declined following arterial balloon injury in vivo (48% at 3d, p < 0.05) and serum stimulation in vitro (45% at 24 h, p < 0.01). Functional studies revealed that miR-22 negatively regulated the proliferation and migration of VSMCs by directly targeting the SP1 transcription factor in VSMCs. Curcumin increased the expression of miR-22 (81%, p < 0.05) and decreased the protein expression of SP1 in VSMCs (25%, p < 0.05). miR-22 inhibition was found to attenuate the effects of curcumin on VSMC functions. Curcumin increased miR-22 (46%, p < 0.01), decreased the SP1 protein (19%, p < 0.05), and inhibited vascular neointimal area (48%, p < 0.01) in vivo.Discussion: The miR-22/SP1 pathway is involved in the protective role of curcumin during arterial balloon injury, but the mechanisms remain unclear.Conclusion: miR-22 is involved in the inhibitory effects of curcumin on VSMCs' proliferation, migration and neointima hyperplasia after arterial balloon injury in rats. Curcumin could be used to prevent neointimal hyperplasia after angioplasty.

Resveratrol, curcumin, paclitaxel and miRNAs mediated regulation of PI3K/Akt/mTOR pathway: go four better to treat bladder cancer

Bladder cancer (BC) is a leading cause of death among urothelial malignancies that more commonly affect male population. Poor prognosis and resistance to chemotherapy are the two most important characteristics of this disease. PI3K/Akt/mTOR signaling pathway has been considered pivotal in the regulation of proliferation, migration, invasiveness, and metastasis. Deregulation of PI3K/Akt/mTOR signaling has been found in 40% of bladder cancers. Several microRNAs (miRNAs) have been reported to interact with the PI3K/Akt/mTOR signaling pathway with a different possible role in proliferation and apoptosis in bladder cancer. Thus, miRNAs can be used as potential biomarkers for BC. Natural compounds have been in the spotlight for the past decade due to their effective anti-proliferative capabilities. However, little is known of its possible effects in bladder cancer. The aim of this review is to discuss the interplay between PI3K/Akt/mTOR, miRNAs, and natural compounds and emphasize the importance of miRNAs as biomarkers and resveratrol, curcumin and paclitaxel as a possible therapeutic approach against bladder cancer.

Curcumin Modifies Epithelial-Mesenchymal Transition in Colorectal Cancer Through Regulation of miR-200c/EPM5

Background

The serious side effect of current conventional treatments for patients with metastatic colorectal cancer (CRC) highlights the requirement of an alternative treatment strategy. Natural compounds, such as curcumin, have been gained much attention due to its low toxicity and anti-tumor effect.

Methods

qPCR and Western blot were used to measure the molecular changes induced by curcumin. Wound-healing assay and transwell assay were conducted to study the effect on cell migration and invasion. RT¹ PCR array was performed to identify the miRNAs involved in curcumin-repressed EMT. Three algorithms and luciferase reporter assay were used to identify EPM5 as a target of miR-200c. The bioinformatical analysis of TCGA-COAD and other CRC cohorts were used to examine the association of EPM5 with EMT signatures and clinical relevance. The ectopic expression or siRNA-mediated knockdown of EPM5 was applied to study the role of EPM5 in CRC.

Results

Treatment with curcumin changed the epithelial–mesenchymal transition (EMT)-related gene expression, repressed cell migration and invasion in CRC cells. Its anti-tumor capability required the upregulation of miR-200c. EPM5 was a direct target of miR-200c and enriched in the consensus molecular subtype (CMS) 4 of CRC. Ectopic expression of EPM5 alone was sufficient to induce EMT in CRC. Downregulation of EPM5 was necessary for curcumin-repressed EMT, migration, and invasion. Higher expression of EPM5 was associated with the advanced TNM stages and poor survival in CRC.

Conclusion

Our data provide the first evidence that the curcumin inhibits EMT in CRC by upregulation of miR-200c and downregulation of EPM5, and the use of curcumin might be able to prevent or delay CRC progression.

The Role of Dietary Phenolic Compounds in Epigenetic Modulation Involved in Inflammatory Processes

A better understanding of the interactions between dietary phenolic compounds and the epigenetics of inflammation may impact pathological conditions and their treatment. Phenolic compounds are well-known for their antioxidant, anti-inflammatory, anti-angiogenic, and anti-cancer properties, with potential benefits in the treatment of various human diseases. Emerging studies bring evidence that nutrition may play an essential role in immune system modulation also by altering gene expression. This review discusses epigenetic mechanisms such as DNA methylation, post-translational histone modification, and non-coding microRNA activity that regulate the gene expression of molecules involved in inflammatory processes. Special attention is paid to the molecular basis of NF-κB modulation by dietary phenolic compounds. The regulation of histone acetyltransferase and histone deacetylase activity, which all influence NF-κB signaling, seems to be a crucial mechanism of the epigenetic control of inflammation by phenolic compounds. Moreover, chronic inflammatory processes are reported to be closely connected to the major stages of carcinogenesis and other non-communicable diseases. Therefore, dietary phenolic compounds-targeted epigenetics is becoming an attractive approach for disease prevention and intervention.

Targeting miRNAs by natural products: A new way for cancer therapy

MicroRNAs (miRNAs) are short non-coding RNAs that regulate gene expression through mRNA degradation or translation inhibition. MiRNAs play important roles in a variety of biological processes, and dysregulation of miRNA expression is highly associated with cancer development. Individual miRNA regulates multiple gene expressions, enabling them to regulate multiple cellular signaling pathways simultaneously. Hence, miRNAs could be served as cancer biomarkers for diagnosis and prognosis, and also therapeutic targets. Recently, more and more evidences showed that natural products such as paclitaxel, curcumin, resveratrol, genistein or epigallocatechin-3-gallate exert their anti-proliferative and/or pro-apoptotic effects through regulating one or more miRNAs, leading to the inhibition of cancer cell growth, induction of apoptosis or enhancement of conventional cancer therapeutic efficacy. Herein, we outlined the recent advances in the regulation of miRNAs expression by the natural products and highlight the importance of these natural drugs as a potential strategy in cancer treatment. This review will help us better understand how natural products modulate miRNAs and contribute to the development of effective and safe natural drugs for therapeutic purposes.