Sulforaphane causes epigenetic repression of hTERT expression in human breast cancer cell lines

Synergic Role of Dietary Bioactive Compounds in Breast Cancer Chemoprevention and Combination Therapies

Breast cancer is the most common tumor in women. Chemotherapy is the gold standard for cancer treatment; however, severe side effects and tumor resistance are the major obstacles to chemotherapy success. Numerous dietary components and phytochemicals have been found to inhibit the molecular and signaling pathways associated with different stages of breast cancer development. In particular, this review is focused on the antitumor effects of PUFAs, dietary enzymes, and glucosinolates against breast cancer. The major databases were consulted to search in vitro and preclinical studies; only those with solid scientific evidence and reporting protective effects on breast cancer treatment were included. A consistent number of studies highlighted that dietary components and phytochemicals can have remarkable therapeutic effects as single agents or in combination with other anticancer agents, administered at different concentrations and via different routes of administration. These provide a natural strategy for chemoprevention, reduce the risk of breast cancer recurrence, impair cell proliferation and viability, and induce apoptosis. Some of these bioactive compounds of dietary origin, however, show poor solubility and low bioavailability; hence, encapsulation in nanoformulations are promising tools able to increase clinical efficiency.

Involvement of CCCTC-binding factor in epigenetic regulation of cancer

A major global health burden continues to be borne by the complex and multifaceted disease of cancer. Epigenetic changes, which are essential for the emergence and spread of cancer, have drawn a huge amount of attention recently. The CCCTC-binding factor (CTCF), which takes part in a wide range of cellular processes including genomic imprinting, X chromosome inactivation, 3D chromatin architecture, local modifications of histone, and RNA polymerase II-mediated gene transcription, stands out among the diverse array of epigenetic regulators. CTCF not only functions as an architectural protein but also modulates DNA methylation and histone modifications. Epigenetic regulation of cancer has already been the focus of plenty of studies. Understanding the role of CTCF in the cancer epigenetic landscape may lead to the development of novel targeted therapeutic strategies for cancer. CTCF has already earned its status as a tumor suppressor gene by acting like a homeostatic regulator of genome integrity and function. Moreover, CTCF has a direct effect on many important transcriptional regulators that control the cell cycle, apoptosis, senescence, and differentiation. As we learn more about CTCF-mediated epigenetic modifications and transcriptional regulations, the possibility of utilizing CTCF as a diagnostic marker and therapeutic target for cancer will also increase. Thus, the current review intends to promote personalized and precision-based therapeutics for cancer patients by shedding light on the complex interplay between CTCF and epigenetic processes.

NRF2 signaling pathway and telomere length in aging and age-related diseases

The transcription factor nuclear factor erythroid 2-related factor 2 (NRF2) is well recognized as a critical regulator of redox, metabolic, and protein homeostasis, as well as the regulation of inflammation. An age-associated decline in NRF2 activity may allow oxidative stress to remain unmitigated and affect key features associated with the aging phenotype, including telomere shortening. Telomeres, the protective caps of eukaryotic chromosomes, are highly susceptible to oxidative DNA damage, which can accelerate telomere shortening and, consequently, lead to premature senescence and genomic instability. In this review, we explore how the dysregulation of NRF2, coupled with an increase in oxidative stress, might be a major determinant of telomere shortening and age-related diseases. We discuss the relevance of the connection between NRF2 deficiency in aging and telomere attrition, emphasizing the importance of studying this functional link to enhance our understanding of aging pathologies. Finally, we present a number of compounds that possess the ability to restore NRF2 function, maintain a proper redox balance, and preserve telomere length during aging.

Blue Light Enhances Health-Promoting Sulforaphane Accumulation in Broccoli (Brassica oleracea var. italica) Sprouts through Inhibiting Salicylic Acid Synthesis

As a vegetable with high nutritional value, broccoli (Brassica oleracea var. italica) is rich in vitamins, antioxidants and anti-cancer compounds. Glucosinolates (GLs) are one of the important functional components widely found in cruciferous vegetables, and their hydrolysate sulforaphane (SFN) plays a key function in the anti-cancer process. Herein, we revealed that blue light significantly induced the SFN content in broccoli sprouts, and salicylic acid (SA) was involved in this process. We investigated the molecular mechanisms of SFN accumulation with blue light treatment in broccoli sprouts and the relationship between SFN and SA. The results showed that the SFN accumulation in broccoli sprouts was significantly increased under blue light illumination, and the expression of SFN synthesis-related genes was particularly up-regulated by SA under blue light. Moreover, blue light considerably decreased the SA content compared with white light, and this decrease was more suppressed by paclobutrazol (Pac, an inhibitor of SA synthesis). In addition, the transcript level of SFN synthesis-related genes and the activity of myrosinase (MYR) paralleled the trend of SFN accumulation under blue light treatment. Overall, we concluded that SA participates in the SFN accumulation in broccoli sprouts under blue light.

Regulation and clinical potential of telomerase reverse transcriptase (TERT/hTERT) in breast cancer

Telomerase reverse transcriptase (TERT/hTERT) serves as the pivotal catalytic subunit of telomerase, a crucial enzyme responsible for telomere maintenance and human genome stability. The high activation of hTERT, observed in over 90% of tumors, plays a significant role in tumor initiation and progression. An in-depth exploration of hTERT activation mechanisms in cancer holds promise for advancing our understanding of the disease and developing more effective treatment strategies. In breast cancer, the expression of hTERT is regulated by epigenetic, transcriptional, post-translational modification mechanisms and DNA variation. Besides its canonical function in telomere maintenance, hTERT exerts non-canonical roles that contribute to disease progression through telomerase-independent mechanisms. This comprehensive review summarizes the regulatory mechanisms governing hTERT in breast cancer and elucidates the functional implications of its activation. Given the overexpression of hTERT in most breast cancer cells, the detection of hTERT and its associated molecules are potential for enhancing early screening and prognostic evaluation of breast cancer. Although still in its early stages, therapeutic approaches targeting hTERT and its regulatory molecules show promise as viable strategies for breast cancer treatment. These methods are also discussed in this paper. Video Abstract.

Paternal Combined Botanicals Contribute to the Prevention of Estrogen Receptor-Negative Mammary Cancer in Transgenic Mice

BACKGROUND

Parental nutritional interventions have considerably affected gametogenesis and embryogenesis, leading to the differential susceptibility of offspring to chronic diseases such as cancer. Moreover, combinatorial bioactive diets are more efficacious in ameliorating epigenetic aberrations in tumorigenesis.

OBJECTIVES

We sought to investigate the transgenerational influence and epigenetic regulation of paternal sulforaphane (SFN)-rich broccoli sprouts (BSp) and epigallocatechin-3-gallate (EGCG)-rich green tea polyphenols (GTPs) consumption in the prevention of estrogen receptor-negative [ER(-)] mammary cancer in transgenic mice.

METHODS

Human breast cancer cells were used to detect cell viability and epigenetic-related gene expression after treatment with EGCG and/or SFN. Twenty-four C3 or HER2/neu males were randomly assigned into 4 groups and treated with control, 26% BSp (w/w) in food, 0.5% GTPs (w/v) in drinking water or combined BSp and GTPs for 7 wk before mating. Tumor growth of nontreated female pups was monitored weekly for 19 wk (C3) and 25 wk (HER2/neu). Tumor- and epigenetic-related protein expression and enzyme activities in mammary tumors were measured. Sperms were isolated from treated males for RNA sequencing and reduced-representation bisulfite sequencing analysis. Data were analyzed with a 2-factor or 3-factor analysis of variance.

RESULTS

EGCG and SFN inhibited breast cancer cell growth via epigenetic regulation. Combined BSp and GTPs synergistically (combination index < 1) suppressed tumor growth over time (P < 0.001) in 2 mouse models. Key tumor-related proteins were found differentially expressed (P < 0.05) along with epigenetic regulations in offspring mammary tumors. The transcriptome profile of sperm derived from dietary-treated males revealed differentially expressed genes correlated with spermatogenesis and breast cancer progression. DNA methylomes of the sperm and further integrated analysis with transcriptomes indicate that DNA methylation alone may not contribute to sufficient regulation in dietary-treated sperm pronucleus, leading to offspring tumor suppression.

CONCLUSIONS

Collectively, paternal consumption of combined BSp and GTPs shows potential for preventing ER(-) mammary cancer through transgenerational effects. J Nutr 2023;xx:xx-xx.

Mikania micrantha extract enhances cutaneous wound healing activity through the activation of FAK/Akt/mTOR cell signaling pathway

Mikania micrantha (MM) has been traditionally used for various health benefits, including mental health, anti-inflammatory, wound dressing, and healing of sores. However, the molecular mechanisms and dose required for the wound healing activity of MM have yet to be reported. Therefore, a study was conducted to evaluate the wound healing potential of a cold methanolic extract of MM through in vitro and in vivo studies. Human dermal fibroblast adult (HDFa) cells were treated with 0 (control), 75 ng/ml, 125 ng/ml, 250 ng/ml, and 500 ng/ml of MMmethanolic extract (MME) for 24 h. MME at 75 ng/ml has significantly (p˂0.05) promoted HDFa cell proliferation and migration. Further, MME has also been shown to enhance the invasiveness of human umbilical vascular endothelial cells (HUVECs), indicating the neovasculature for wound healing. The tube formation assay demonstrated a significant (p<0.05) increase in the angiogenic effect of the MME starting at a concentration of 75 ng/ml as compared to the control. Treatment of excision wounds in Wistar rats with 5% and 10% MME ointment significantly enhanced wound contraction compared to control animals. Incision wounds in rats treated with 5% and 10% MME showed a significant (p<0.01) increase in tensile strength compared to control. HDFa cells, and granulation tissue collected on day 14 post-wounding, revealed the modulation of the FAK/Akt/mTOR cell signaling pathway during the enhancement of wound healing. The results of gel zymography showed increased activity of MMP-2 and MMP-9 in the HDFa cells after treatment with the extract.  It is concluded that MMEcan potentially accelerate cutaneous wound healing.

Lunasin and Its Epigenetic Impact in Cancer Chemoprevention

Cancer diseases are a leading cause of death worldwide. Therefore, it is pivotal to search for bioactive dietary compounds that can avert tumor development. A diet rich in vegetables, including legumes, provides chemopreventive substances, which have the potential to prevent many diseases, including cancer. Lunasin is a soy-derived peptide whose anti-cancer activity has been studied for over 20 years. The results of the previous research have shown that lunasin inhibits histone acetylation, regulates the cell cycle, suppresses proliferation and induces apoptosis of cancer cells. Thus, lunasin seems to be a promising bioactive anti-cancer agent and a potent epigenetic modulator. The present review discusses studies of the underlying molecular mechanisms and new perspectives on lunasin application in epigenetic prevention and anti-cancer therapy.

Reviewing the Prospective Pharmacological Potential of Isothiocyanates in Fight against Female-Specific Cancers

Gynecological cancers are the most commonly diagnosed malignancies in females worldwide. Despite the advancement of diagnostic tools as well as the availability of various therapeutic interventions, the incidence and mortality of female-specific cancers is still a life-threatening issue, prevailing as one of the major health problems worldwide. Lately, alternative medicines have garnered immense attention as a therapeutic intervention against various types of cancers, seemingly because of their safety profiles and enhanced effectiveness. Isothiocyanates (ITCs), specifically sulforaphane, benzyl isothiocyanate, and phenethyl isothiocyanate, have shown an intriguing potential to actively contribute to cancer cell growth inhibition, apoptosis induction, epigenetic alterations, and modulation of autophagy and cancer stem cells in female-specific cancers. Additionally, it has been shown that ITCs plausibly enhance the chemo-sensitization of many chemotherapeutic drugs. To this end, evidence has shown enhanced efficacy in combinatorial regimens with conventional chemotherapeutic drugs and/or other phytochemicals. Reckoning with these, herein, we discuss the advances in the knowledge regarding the aspects highlighting the molecular intricacies of ITCs in female-specific cancers. In addition, we have also argued regarding the potential of ITCs either as solitary treatment or in a combinatorial therapeutic regimen for the prevention and/or treatment of female-specific cancers. Hopefully, this review will open new horizons for consideration of ITCs in therapeutic interventions that would undoubtedly improve the prognosis of the female-specific cancer clientele. Considering all these, it is reasonable to state that a better understanding of these molecular intricacies will plausibly provide a facile opportunity for treating these female-specific cancers.

Prospective Epigenetic Actions of Organo-Sulfur Compounds against Cancer: Perspectives and Molecular Mechanisms

Major epigenetic alterations, such as chromatin modifications, DNA methylation, and miRNA regulation, have gained greater attention and play significant roles in oncogenesis, representing a new paradigm in our understanding of cancer susceptibility. These epigenetic changes, particularly aberrant promoter hypermethylation, abnormal histone acetylation, and miRNA dysregulation, represent a set of epigenetic patterns that contribute to inappropriate gene silencing at every stage of cancer progression. Notably, the cancer epigenome possesses various HDACs and DNMTs, which participate in the histone modifications and DNA methylation. As a result, there is an unmet need for developing the epigenetic inhibitors against HDACs and DNMTs for cancer therapy. To date, several epigenetically active synthetic inhibitors of DNA methyltransferases and histone deacetylases have been developed. However, a growing body of research reports that most of these synthetic inhibitors have significant side effects and a narrow window of specificity for cancer cells. Targeting tumor epigenetics with phytocompounds that have the capacity to modulate abnormal DNA methylation, histone acetylation, and miRNAs expression is one of the evolving strategies for cancer prevention. Encouragingly, there are many bioactive phytochemicals, including organo-sulfur compounds that have been shown to alter the expression of key tumor suppressor genes, oncogenes, and oncogenic miRNAs through modulation of DNA methylation and histones in cancer. In addition to vitamins and microelements, dietary phytochemicals such as sulforaphane, PEITC, BITC, DADS, and allicin are among a growing list of naturally occurring anticancer agents that have been studied as an alternative strategy for cancer treatment and prevention. Moreover, these bioactive organo-sulfur compounds, either alone or in combination with other standard cancer drugs or phytochemicals, showed promising results against many cancers. Here, we particularly summarize and focus on the impact of specific organo-sulfur compounds on DNA methylation and histone modifications through targeting the expression of different DNMTs and HDACs that are of particular interest in cancer therapy and prevention.

Genome-Wide Analysis on Transcriptome and Methylome in Prevention of Mammary Tumor Induced by Early Life Combined Botanicals

Breast cancer (BC) is the most common malignancy and the second leading cause of cancer death among women in the United States. The consumption of natural dietary components such as broccoli sprouts (BSp) and green tea polyphenols (GTPs) has demonstrated exciting potential in reducing the risk of BC through the regulation of epigenetic mechanisms. However, little is known about their impacts on reversing epigenomic aberrations that are centrally involved in the initiation and progression of BC. Previously, we have determined the efficacy of combined BSp and GTPs treatment on the inhibition of the growth of a mammary tumor in a transgenic Her2/neu mouse model. We sought to extend our previous study to identify universal biomarkers that represent common mechanistic changes among different mouse models in response to this dietary regime by including a new transgenic mouse model, C3(1)-SV40 TAg (SV40). As a result, we identified novel target genes that were differentially expressed and methylated in response to dietary botanicals when administered singly (BSp and GTPs) and in combination (BSp + GTPs) in both mouse models. We discovered more differentially expressed and methylated genes in the combination treatment group compared to the singly administered groups. Subsequently, several biological pathways related to epigenetic regulations were identified in response to the combination treatment. Furthermore, when compared to the BSp and GTPs treatment alone, the combinatorial treatment showed a more significant impact on the regulation of the epigenetic modifier activities involved in DNA methylation and histone modifications. Our study provides key insights about the impact of the combined administration of BSp and GTPs on BC using a multi-omics analysis, suggesting a combinatorial approach is more efficacious in preventing and inhibiting BC by impacting key tumor-related genes at transcriptomic and methylomic levels. Our findings could be further extrapolated as a comprehensive source for understanding the epigenetic modifications that are associated with the effects of these dietary botanicals on BC prevention.

Epigenetic regulation by metabolites from the gut microbiome

The gut microbiome can metabolise food components, such as dietary fibres and various phytochemicals; and the microbiome can also synthesise some nutrients, for example B vitamins. The metabolites produced by bacteria and other micro-organisms in the colon can have implications for health and disease risk. Some of these metabolites are epigenetically active, and can contribute to changes in the chemical modification and structure of chromatin by affecting the activity and expression of epigenetically-active enzymes, for example histone deacetylases and DNA methyltransferases. The epigenetic activity of such gut microbiome metabolites is reviewed herein.

Diindolylmethane Promotes Metabolic Crisis and Enhances the Efficacy of Centchroman in Breast Cancer: A 1H NMR-Based Approach

Diindolylmethane (DIM) is a key metabolite of indole-3-carbinol found in cruciferous vegetables such as broccoli, cauliflower, and cabbage. DIM has been known for its anti-cancerous activity through various mechanisms. Most cancer cells, including triple-negative breast cancer (TNBC), adapt distinct metabolic reprogramming for rapid growth and proliferation. Hence, targeting metabolic dysregulation may provide a favorable therapeutic condition for the treatment of TNBC. Earlier, we found that DIM increases the intracellular accumulation of Centchroman (CC), a potential anticancer agent, thereby enhancing the therapeutic potential of CC against breast cancer. However, the role of DIM in regulating TNBC cellular metabolism remains unknown. In the current study, we investigated the potential therapeutic interventions of DIM in TNBC and its metabolic reprogramming in enhancing the efficacy of CC. We found that DIM induced metabolic catastrophe in TNBC cells by regulating aerobic glycolysis and intermediate metabolism. Further, the DIM and CC combination significantly inhibited the TNBC tumor growth in the 4T1-syngeneic model. The inhibition of tumor growth was associated with the downregulation of key aerobic glycolysis mediators such as PKM2, GLUT1, and hypoxia-inducible factor 1α (HIF-1α). This is a first-of-a-kind investigation linking DIM with aerobic glycolysis regulation and enhancing the treatment efficacy of CC against TNBC. Therefore, these findings suggest that DIM-based nutraceuticals and functional foods can be developed as adjuvant therapy for treating metabolically dysregulated TNBC.

Microbial dysbiosis and epigenetics modulation in cancer development - A chemopreventive approach

An overwhelming number of research articles have reported a strong relationship of the microbiome with cancer. Microbes have been observed more commonly in the body fluids like urine, stool, mucus of people with cancer compared to the healthy controls. The microbiota is responsible for both progression and suppression activities of various diseases. Thus, to maintain healthy human physiology, host and microbiota relationship should be in a balanced state. Any disturbance in this equilibrium, referred as microbiome dysbiosis becomes a prime cause for the human body to become more prone to immunodeficiency and cancer. It is well established that some of these microbes are the causative agents, whereas others may encourage the formation of tumours, but very little is known about how these microbial communications causing change at gene and epigenome level and trigger as well as encourage the tumour growth. Various studies have reported that microbes in the gut influence DNA methylation, DNA repair and DNA damage. The genes and pathways that are altered by gut microbes are also associated with cancer advancement, predominantly those implicated in cell growth and cell signalling pathways. This study exhaustively reviews the current research advancements in understanding of dysbiosis linked with colon, lung, ovarian, breast cancers and insights into the potential molecular targets of the microbiome promoting carcinogenesis, the epigenetic alterations of various potential targets by altered microbiota, as well as the role of various chemopreventive agents for timely prevention and customized treatment against various types of cancers.

Implication of the Mediterranean diet on the human epigenome

Epigenetics, defined as "hereditary changes in gene expression that occur without any change in the DNA sequence", consists of various epigenetic marks, including DNA methylation, histone modifications, and non-coding RNAs. The epigenome, which has a dynamic structure in response to intracellular and extracellular stimuli, has a key role in the control of gene activity, since it is located at the intersection of cellular information encoded in the genome and molecular/chemical information of extracellular origin. The focus shift of studies to epigenetic reprogramming has led to the formation and progressive importance of a concept called "nutriepigenetics", whose aim is to prevent diseases by intervening on nutrition style. Among the diet types adopted in the world, the renowned Mediterranean Diet (MD), being rich in unsaturated fatty acids and containing high levels of whole grain foods and large quantities of fruits, vegetables, and legumes, has shown numerous advantages in excluding chronic diseases. Additionally, the fact that this diet is rich in polyphenols with high antioxidant and anti-inflammatory properties has an undeniable effect in turning some cellular pathways against the disease. It is also apparent that the effects of polyphenols on the epigenome cause changes in mechanisms such as DNA methylation and histone acetylation/deacetylation, which have a regulatory effect on gene regulation. This review presents the effects of long-term consumption of nutrients from the MD on the epigenome and discusses the benefits of this diet in the treatment and even prevention of chronic diseases.

The Anticancer Potential of Plant-Derived Nutraceuticals via the Modulation of Gene Expression

Current studies show that approximately one-third of all cancer-related deaths are linked to diet and several cancer forms are preventable with balanced nutrition, due to dietary compounds being able to reverse epigenetic abnormalities. An appropriate diet in cancer patients can lead to changes in gene expression and enhance the efficacy of therapy. It has been demonstrated that nutraceuticals can act as powerful antioxidants at the cellular level as well as anticarcinogenic agents. This review is focused on the best studies on worldwide-available plant-derived nutraceuticals: curcumin, resveratrol, sulforaphane, indole-3-carbinol, quercetin, astaxanthin, epigallocatechin-3-gallate, and lycopene. These compounds have an enhanced effect on epigenetic changes such as histone modification via HDAC (histone deacetylase), HAT (histone acetyltransferase) inhibition, DNMT (DNA methyltransferase) inhibition, and non-coding RNA expression. All of these nutraceuticals are reported to positively modulate the epigenome, reducing cancer incidence. Furthermore, the current review addresses the issue of the low bioavailability of nutraceuticals and how to overcome the drawbacks related to their oral administration. Understanding the mechanisms by which nutraceuticals influence gene expression will allow their incorporation into an “epigenetic diet” that could be further capitalized on in the therapy of cancer.

Quantitative Expression of SFN, lncRNA CCDC18-AS1, and lncRNA LINC01343 in Human Breast Cancer as the Regulator Biomarkers in a Novel ceRNA Network: Based on Bioinformatics and Experimental Analyses

Breast cancer (BC) is one of the leading cancers in the world, which has become an increasing serious problem. In this context, reports demonstrate that some long noncoding RNAs (lncRNAs) play significant regulatory roles in breast tumorigenesis and BC progression via various pathways and act as endogenous RNAs. Finding their dysregulation in cancer and evaluating their interaction with other molecules, such as short noncoding RNAs “microRNA (miRNAs)” as well as various genes, are the most important parts in cancer diagnostics. In this study, after performing GSEA and microarray analysis on the GSE71053 dataset, a new ceRNA network of CCDC18-AS1, LINC01343, hsa-miR4462, and SFN in BC was detected by bioinformatics analysis. Therefore, the expression of SFN, CCDC18-AS1, and LINC01343 was quantitatively measured in 24 BC and normal paired tissues using qRT-PCR. CCDC18-AS1, LINC01343, and SFN were expressed higher in BC than in the control (normal paired) tissues based on qRT-PCR data. Furthermore, a significant positive correlation was observed between CCDC18-AS1 and LINC01343 expression in the samples investigated in this study. The investigation of clinicopathological parameters showed that SFN was highly expressed in tumor size of <5 cm and in nonmenopausal ages, while CCDC18-AS1 and LINC01343 indicated a high expression in stages II-III and III of BC, respectively. The overall survival analysis displayed high and low survival in patients with high expression of SFN and CCDC18-AS1, respectively. The ROC curve analysis disclosed that SFN, CCDC18-AS1, and LINC01343 might be suggested as potential biological markers in BC patients. The high expression of CCDC18-AS1, LINC01343, and SFN in BC samples suggests their potential role in BC tumorigenesis and could be considered hallmarks for the diagnosis and prognosis of BC, although this will require further clinical investigations.

Extract of Murraya koenigii selectively causes genomic instability by altering redox-status via targeting PI3K/AKT/Nrf2/caspase-3 signaling pathway in human non-small cell lung cancer

BACKGROUND

Lung cancer is the leading cause of cancer-related death worldwide. Dietary bioactives have been used as alternative therapeutics to overcome various adverse effects caused by chemotherapeutics. Curry leaves are a widely used culinary spice and different parts of this plant have been used in traditional medicines. Curry leaves are a rich source of multiple bioactives, especially polyphenols and alkaloids. Therefore, extraction processes play a key role in obtaining the optimum yield of bioactives and their efficacy.

PURPOSE

We aim to select an extraction process that achieves the optimum yield of bioactives in curry leaves crude extract (CLCE) with minimum solvent usage and in a shorter time. Further, to investigate the anticancer properties of CLCE and its mechanism against lung cancer.

METHODS

Different extraction processes were performed and analyzed polyphenol content. The bioactives and essential oils present in curry leaves were identified through LC-MS/MS and GC-MS analysis. The cytotoxicity of microwave-assisted CLCE (MA-CLCE) was investigated through MTT and colony-forming assays. The DNA damage was observed by comet assay. The apoptotic mechanisms of MA-CLCE were investigated by estimating ROS production, depolarization of mitochondrial membrane potential (MMP), and apoptotic proteins. The glutathione assay estimated the antioxidant potential of MA-CLCE in normal cells.

RESULTS

Generally, conventional extraction methods require high temperatures, extra energy input, and time. Recently, green extraction processes are getting wider attention as alternative extraction methods. This study compared different extraction processes and found that the microwave-assisted extraction (MAE) method yields the highest polyphenols from curry leaves among other extraction processes with minimum processing. The MA-CLCE functions as an antioxidant under normal physiological conditions but pro-oxidant to cancer cells. MA-CLCE scavenges free radicals and enhances the intracellular GSH level in alveolar macrophages in situ. We found that MA-CLCE selectively inhibits cell proliferation and induces apoptosis in cancer cells by altering cellular redox status. MA-CLCE induces chromatin condensation and genotoxicity through ROS-induced depolarization of MMP. The depolarization of MMP causes the release of cytochrome c into the cytosol and activates the apoptotic pathway in lung cancer cells. However, pretreatment with ascorbic acid, an antioxidant, inhibits the MA-CLCE-induced apoptosis by reducing ROS production, which impedes mitochondrial membrane disruption, preventing BAX/BCL-2 expression alteration. Simultaneously, MA-CLCE downregulates the expression of survival signaling regulator PI3K/AKT, which modulates Nrf-2. MA-CLCE also diminishes intracellular antioxidant proficiency by suppressing Nrf-2 expression, followed by HO-1 expressions.

CONCLUSION

Among several extraction methods, MA-CLCE is rich in several bioactives, especially polyphenols, alkaloids, and essential oils. Here, we reported for the first time that MA-CLCE functions as a pro-oxidant to lung cancer cells and acts as an antioxidant to normal cells by regulating different cellular programs and signaling pathways. Therefore, it can be further developed as a promising phytomedicine against lung cancer.

Modulating Microbiota as a New Strategy for Breast Cancer Prevention and Treatment

Breast cancer (BC) is the most common cancer in women in the United States. There has been an increasing incidence and decreasing mortality rate of BC cases over the past several decades. Many risk factors are associated with BC, such as diet, aging, personal and family history, obesity, and some environmental factors. Recent studies have shown that healthy individuals and BC patients have different microbiota composition, indicating that microbiome is a new risk factor for BC. Gut and breast microbiota alterations are associated with BC prognosis. This review will evaluate altered microbiota populations in gut, breast tissue, and milk of BC patients, as well as mechanisms of interactions between microbiota modulation and BC. Probiotics and prebiotics are commercially available dietary supplements to alleviate side-effects of cancer therapies. They also shape the population of human gut microbiome. This review evaluates novel means of modulating microbiota by nutritional treatment with probiotics and prebiotics as emerging and promising strategies for prevention and treatment of BC. The mechanistic role of probiotic and prebiotics partially depend on alterations in estrogen metabolism, systematic immune regulation, and epigenetics regulation.

Herbal Ingredients in the Prevention of Breast Cancer: Comprehensive Review of Potential Molecular Targets and Role of Natural Products

Among various cancers, breast cancer is the most prevalent type in women throughout the world. Breast cancer treatment is challenging due to complex nature of the etiology of disease. Cell division cycle alterations are often encountered in a variety of cancer types including breast cancer. Common treatments include chemotherapy, surgery, radiotherapy, and hormonal therapy; however, adverse effects and multidrug resistance lead to complications and noncompliance. Accordingly, there is an increasing demand for natural products from medicinal plants and foods. This review summarizes molecular mechanisms of signaling pathways in breast cancer and identifies mechanisms by which natural compounds may exert their efficacy in the treatment of breast cancer.

Traditional uses, phytochemistry, transformation of ingredients and pharmacology of the dried seeds of Raphanus sativus L. (Raphani Semen), A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Raphani Semen (Lai Fu-zi in Chinese, RS), the dried seeds of Raphanus sativus L., is a traditional Chinese herbal medicine. RS has long been used for eliminating bloating and digestion, antitussive, expectorant and anti-asthmatic in clinical treatment of traditional Chinese medicine.

AIM OF THE STUDY

This review provides a critical and comprehensive summary of traditional uses, phytochemistry, transformation of ingredients and pharmacology of RS based on research data that have been reported, aiming at providing a basis for further study on RS.

MATERIALS AND METHODS

The search terms "Raphani Semen", "the seeds of Raphanus sativus L." and "radish seed" were used to obtain the information from electronic databases such as Web of Science, China National Knowledge Infrastructure, PubMed and other web search instruments. Traditional uses, phytochemistry, transformation of ingredients and pharmacology of RS were summarized.

RESULTS

RS has been traditionally used to treat food dyspeptic retention, distending pain in the epigastrium and abdomen, constipation, diarrhea and dysentery, panting, and cough with phlegm congestion in the clinical practice. The chemical constituents of RS include glucosinolates and sulfur-containing derivatives, phenylpropanoid sucrosides, small organic acids and derivatives, flavone glycosides, alkaloids, terpenoids, steroids, oligosaccharides and others. Among them, glucosinolates can be transformated to isothiocyanates by plant myrosinase or the intestinal flora, which display a variety of activities, such as anti-tumor, anti-inflammatory, antioxidant, antibacterial, treatment of metabolic diseases, central nervous system protection, anti-osteoporosis. RS has a variety of pharmacological activities, including treatment of metabolic diseases, anti-inflammatory, anti-tumor, antioxidant, antibacterial, antihypertensive, central nervous system protection, anti-osteoporosis, etc. This review will provide useful insight for exploration, further study and precise medication of RS in the future.

CONCLUSIONS

According to its traditional uses, phytochemistry, transformation of ingredients and pharmacology, RS is regarded as a promising medical plant with various chemical compounds and numerous pharmacological activities. However, the material bases and mechanisms of traditional effect of RS need further study.

Telomere length and vitamin B12

Telomeres are non-coding nucleoprotein structures consisting of a highly conserved tandem repeat DNA sequence that caps the ends of chromosomes in eukaryotes. Telomeres confer chromosomal stability, protect the genome from nucleolytic degradation, avoid aberrant recombination and improper repair, and prevent random fusion of chromosomes. The end-replication problem results in telomere shortening with every cell division, eventually leading to cellular senescence and aging. Telomere length (TL) is thereby an ideal candidate for "biological aging." Telomeres possess guanine-rich repeats, which are highly susceptible to oxidative stress. Epidemiological studies have indicated the association of telomere attrition with mortality and various age-related diseases. Micronutrients comprising vitamins and minerals act as potential modulators of stress and can influence TL. Research has indicated that vitamin B12 (B12) regulates oxidative stress and maintains genomic stability, thereby influencing telomere integrity and cellular aging. The deficiency of B12 leads to elevated levels of homocysteine, which reduces the methylation potential and increases oxidative stress, thereby compromising the TL. Telomere shortening and mitochondrial dysfunction are independently linked to aging. However, they are connected through telomerase reverse transcriptase activity, which regulates mitochondrial biogenesis. Further, experimental evidence indicated the positive association of B12 with relative TL and mitochondrial DNA copy number, an indirect index of mitochondrial biogenesis. The present chapter provides some insights into the role of B12 in influencing TL. Exploring their association might open new avenues to understand the pathophysiology of aging and age-related diseases.

Natural Bioactive Compounds Targeting Histone Deacetylases in Human Cancers: Recent Updates

Cancer is a complex pathology that causes a large number of deaths worldwide. Several risk factors are involved in tumor transformation, including epigenetic factors. These factors are a set of changes that do not affect the DNA sequence, while modifying the gene’s expression. Histone modification is an essential mark in maintaining cellular memory and, therefore, loss of this mark can lead to tumor transformation. As these epigenetic changes are reversible, the use of molecules that can restore the functions of the enzymes responsible for the changes is therapeutically necessary. Natural molecules, mainly those isolated from medicinal plants, have demonstrated significant inhibitory properties against enzymes related to histone modifications, particularly histone deacetylases (HDACs). Flavonoids, terpenoids, phenolic acids, and alkaloids exert significant inhibitory effects against HDAC and exhibit promising epi-drug properties. This suggests that epi-drugs against HDAC could prevent and treat various human cancers. Accordingly, the present study aimed to evaluate the pharmacodynamic action of different natural compounds extracted from medicinal plants against the enzymatic activity of HDAC.

DNA Methylation of T Lymphocytes as a Therapeutic Target: Implications for Rheumatoid Arthritis Etiology

Rheumatoid arthritis (RA) is an autoimmune disease that can cause joint damage and disability. Epigenetic variation, especially DNA methylation, has been shown to be involved in almost all the stages of the pathology of RA, from autoantibody production to various self-effector T cells and the defects of protective T cells that can lead to chronic inflammation and erosion of bones and joints. Given the critical role of T cells in the pathology of RA, the regulatory functions of DNA methylation in T cell biology remain unclear. In this review, we elaborate on the relationship between RA pathogenesis and DNA methylation in the context of different T cell populations. We summarize the relevant methylation events in T cell development, differentiation, and T cell-related genes in disease prediction and drug efficacy. Understanding the epigenetic regulation of T cells has the potential to profoundly translate preclinical results into clinical practice and provide a framework for the development of novel, individualized RA therapeutics.

An integrated analysis of the effects of maternal broccoli sprouts exposure on transcriptome and methylome in prevention of offspring mammary cancer

Broccoli sprouts (BSp), a cruciferous vegetable, has shown promising effects on prevention of many types of cancer including breast cancer (BC). BC has a developmental foundation, and maternal nutrition status may influence an offspring’s risk to BC later in life. What is less understood, however, is the influence of maternal nutrition intervention on reversing epigenomic abnormalities that are essential in BC programming during early development. Our research focused on how maternal exposure to BSp diet prevents offspring BC and investigation of possible epigenetic mechanisms during these processes. Our results showed that maternal feeding of BSp can prevent mammary tumor development in the offspring of a transgenic mouse model. Through comprehensive integrated multi-omics studies on transcriptomic and methylomic analysis, we identified numerous target genes exhibiting significantly differential gene expression and DNA methylation patterns in the offspring mammary tumor. We discovered that maternal exposure to BSp diet can induce both gene and methylation changes in several key genes such as Avpr2, Cyp4a12b, Dpp6, Gria2, Pcdh9 and Tspan11 that are correlated with pivotal biological functions during carcinogenesis. In addition, we found an impact of maternal BSp treatment on DNA methyltransferase and histone deacetylases activity. Our study provides knowledgeable information regarding how maternal BSp diet influences key tumor-related gene expression and the epigenetic changes using a genome-wide perspective. Additionally, these findings provide mechanistic insights into the effectiveness of maternal BSp administration on the prevention of BC in the offspring later in life, which may lead to an early-life BC chemopreventive strategy that benefits the progenies’ long-term health.

Nanoparticles as phytochemical carriers for cancer treatment: News of the last decade

INTRODUCTION

The development and application of novel therapeutic medicines for the treatment of cancer are of vital importance to improve the disease's outcome and survival rate. One noteworthy treatment approach is the use of biologically active compounds present in natural products. Even though these phytocompounds present anti-inflammatory, antioxidant, and anticancer properties, their use is limited essentially due to poor systemic delivery, low bioavailability, and water solubility concerns. To make full use of the anticancer potential of natural products, these limitations need to be technologically addressed. In this sense, nanotechnology emerges as a promising drug delivery system strategy.

AREAS COVERED

In this review, the benefits and potential of nanodelivery systems for natural products encapsulation as promising therapeutic approaches for cancer, which were developed during the last decade, are highlighted.

EXPERT OPINION

The nanotechnology area has been under extensive research in the medical field given its capacity for improving the therapeutic potential of drugs by increasing their bioavailability and allowing a targeted delivery to the tumor site. Thereby, the nanoencapsulation of phytocompounds can have a direct impact on the recognized therapeutic activity of natural products towards cancer.

The Role of Glucosinolates from Cruciferous Vegetables (Brassicaceae) in Gastrointestinal Cancers: From Prevention to Therapeutics

The gastrointestinal (GI) tract is composed of rapidly renewing cells, which increase the likelihood of cancer. Colorectal cancer is one of the most frequently diagnosed GI cancers and currently stands in second place regarding cancer-related mortality. Unfortunately, the treatment of GI is limited, and few developments have occurred in the field over the years. With this in mind, new therapeutic strategies involving biologically active phytocompounds are being evaluated as anti-cancer agents. Vegetables such as broccoli, brussels sprouts, cabbage, cauliflower, and radish, all belonging to the Brassicaceae family, are high in dietary fibre, minerals, vitamins, carotenoids, polyphenols, and glucosinolates. The latter compound is a secondary metabolite characteristic of this family and, when biologically active, has demonstrated anti-cancer properties. This article reviews the literature regarding the potential of Cruciferous vegetables in the prevention and/or treatment of GI cancers and the relevance of appropriate compound formulations for improving the stability and bioaccessibility of the major Cruciferous compounds, with a particular focus on glucosinolates.

Novel molecules as the emerging trends in cancer treatment: an update

As per World Health Organization cancer remains as a leading killer disease causing nearly 10 million deaths in 2020. Since the burden of cancer increases worldwide, warranting an urgent search for anti-cancer compounds from natural sources. Secondary metabolites from plants, marine organisms exhibit a novel chemical and structural diversity holding a great promise as therapeutics in cancer treatment. These natural metabolites target only the cancer cells and the normal healthy cells are left unharmed. In the emerging trends of cancer treatment, the natural bioactive compounds have long become a part of cancer chemotherapy. In this review, we have tried to compile about eight bioactive compounds from plant origin viz. combretastatin, ginsenoside, lycopene, quercetin, resveratrol, silymarin, sulforaphane and withaferin A, four marine-derived compounds viz. bryostatins, dolastatins, eribulin, plitidepsin and three microorganisms viz. Clostridium, Mycobacterium bovis and Streptococcus pyogenes with their well-established anticancer potential, mechanism of action and clinical establishments are presented.

Effects and mechanisms of dietary bioactive compounds on breast cancer prevention

Breast cancer (BC) is the most often diagnosed cancer among females globally and has become an increasing global health issue over the last decades. Despite the substantial improvement in screening methods for initial diagnosis, effective therapy remains lacking. Still, there has been high recurrence and disease progression after treatment of surgery, endocrine therapy, chemotherapy, and radiotherapy. Considering this view, there is a crucial requirement to develop safe, freely accessible, and effective anticancer therapy for BC. The dietary bioactive compounds as auspicious anticancer agents have been recognized to be active and their implications in the treatment of BC with negligible side effects. Hence, this review focused on various dietary bioactive compounds as potential therapeutic agents in the prevention and treatment of BC with the mechanisms of action. Bioactive compounds have chemo-preventive properties as they inhibit the proliferation of cancer cells, downregulate the expression of estrogen receptors, and cell cycle arrest by inducing apoptotic settings in tumor cells. Therapeutic drugs or natural compounds generally incorporate engineered nanoparticles with ideal sizes, shapes, and enhance their solubility, circulatory half-life, and biodistribution. All data of in vitro, in vivo, and clinical studies of dietary bioactive compounds and their impact on BC were collected from Science Direct, PubMed, and Google Scholar. The data of chemopreventive and anticancer activity of dietary bioactive compounds were collected and orchestrated in a suitable place in the review. These shreds of data will be extremely beneficial to recognize a series of additional diet-derived bioactive compounds to treat BC with the lowest side effects.

Multiple strategies for the treatment of invasive breast carcinoma: A comprehensive prospective

In this review, we emphasize on evolving therapeutic strategies and advances in the treatment of breast cancer (BC). This includes small-molecule inhibitors under preclinical and clinical investigation, phytoconstituents with antiproliferative potential, targeted therapies as antibodies and antibody-drug conjugates (ADCs), vaccines as immunotherapeutic agents and peptides as a novel approach inhibiting the interaction of oncogenic proteins. We provide an update of molecules under different phases of clinical investigation which aid in the identification of loopholes or shortcomings that can be overcomed with future breast cancer research.

Natural Bioactive Compounds Targeting Epigenetic Pathways in Cancer: A Review on Alkaloids, Terpenoids, Quinones, and Isothiocyanates

Cancer is one of the most complex and systemic diseases affecting the health of mankind, causing major deaths with a significant increase. This pathology is caused by several risk factors, of which genetic disturbances constitute the major elements, which not only initiate tumor transformation but also epigenetic disturbances which are linked to it and which can induce transcriptional instability. Indeed, the involvement of epigenetic disturbances in cancer has been the subject of correlations today, in addition to the use of drugs that operate specifically on different epigenetic pathways. Natural molecules, especially those isolated from medicinal plants, have shown anticancer effects linked to mechanisms of action. The objective of this review is to explore the anticancer effects of alkaloids, terpenoids, quinones, and isothiocyanates.

Influence of the Bioactive Diet Components on the Gene Expression Regulation

Diet bioactive components, in the concept of nutrigenetics and nutrigenomics, consist of food constituents, which can transfer information from the external environment and influence gene expression in the cell and thus the function of the whole organism. It is crucial to regard food not only as the source of energy and basic nutriments, crucial for living and organism development, but also as the factor influencing health/disease, biochemical mechanisms, and activation of biochemical pathways. Bioactive components of the diet regulate gene expression through changes in the chromatin structure (including DNA methylation and histone modification), non-coding RNA, activation of transcription factors by signalling cascades, or direct ligand binding to the nuclear receptors. Analysis of interactions between diet components and human genome structure and gene activity is a modern approach that will help to better understand these relations and will allow designing dietary guidances, which can help maintain good health.

Sulforaphane: A Broccoli Bioactive Phytocompound with Cancer Preventive Potential

Simple Summary

As of the past decade, phytochemicals have become a major target of interest in cancer chemopreventive and chemotherapeutic research. Sulforaphane (SFN) is a metabolite of the phytochemical glucoraphanin, which is found in high abundance in cruciferous vegetables, such as broccoli, watercress, Brussels sprouts, and cabbage. In both distant and recent research, SFN has been shown to have a multitude of anticancer effects, increasing the need for a comprehensive review of the literature. In this review, we critically evaluate SFN as an anticancer agent and its mechanisms of action based on an impressive number of in vitro, in vivo, and clinical studies.

Abstract

There is substantial and promising evidence on the health benefits of consuming broccoli and other cruciferous vegetables. The most important compound in broccoli, glucoraphanin, is metabolized to SFN by the thioglucosidase enzyme myrosinase. SFN is the major mediator of the health benefits that have been recognized for broccoli consumption. SFN represents a phytochemical of high interest as it may be useful in preventing the occurrence and/or mitigating the progression of cancer. Although several prior publications provide an excellent overview of the effect of SFN in cancer, these reports represent narrative reviews that focused mainly on SFN’s source, biosynthesis, and mechanisms of action in modulating specific pathways involved in cancer without a comprehensive review of SFN’s role or value for prevention of various human malignancies. This review evaluates the most recent state of knowledge concerning SFN’s efficacy in preventing or reversing a variety of neoplasms. In this work, we have analyzed published reports based on in vitro, in vivo, and clinical studies to determine SFN’s potential as a chemopreventive agent. Furthermore, we have discussed the current limitations and challenges associated with SFN research and suggested future research directions before broccoli-derived products, especially SFN, can be used for human cancer prevention and intervention.

Impact of Stilbenes as Epigenetic Modulators of Breast Cancer Risk and Associated Biomarkers

With the recent advancement of genetic screening for testing susceptibility to mammary oncogenesis in women, the relevance of the gene−environment interaction has become progressively apparent in the context of aberrant gene expressions. Fetal exposure to external stressors, hormones, and nutrients, along with the inherited genome, impact its traits, including cancer susceptibility. Currently, there is increasing interest in the role of epigenetic biomarkers such as genomic methylation signatures, plasma microRNAs, and alterations in cell-signaling pathways in the diagnosis and primary prevention of breast cancer, as well as its prognosis. Polyphenols like natural stilbenes have been shown to be effective in chemoprevention by exerting cytotoxic effects that can stall cell proliferation. Besides possessing antioxidant properties against the DNA-damaging effects of reactive oxygen species, stilbenes have also been observed to modulate cell-signaling pathways. With the increasing trend of early-life screening for hereditary breast cancer risks, the potency of different phytochemicals in harnessing the epigenetic biomarkers of breast cancer risk demand more investigation. This review will explore means of exploiting the abilities of stilbenes in altering the underlying factors that influence breast cancer risk, as well as the appearance of associated biomarkers.

Sulforaphane as a potential remedy against cancer: Comprehensive mechanistic review

Sulforaphane belongs to the active class of isothiocyanates capable of delivering various biological benefits for health promotion and disease prevention. This compound is considered vital to curtail numerous metabolic disorders. Various studies have proven its beneficial effects against cancer prevention and its possible utilization as a therapeutic agent in cancer treatment. Understanding the mechanistic pathways and possible interactions at cellular and subcellular levels is key to design and develop cancer therapeutics for humans. In this respect, a number of mechanisms such as modulation of carcinogen metabolism & phase II enzymatic activities, cell cycle arrest, activation of Nrf2, cytotoxic, proapoptotic and apoptotic pathways have been reported to be involved in cancer prevention. This article provides sufficient information by critical analysis to understand the mechanisms involved in cancer prevention attributed to sulforaphane. Furthermore, various clinical studies have also been included for design and development of novel therapies for cancer prevention and cure. PRACTICAL APPLICATIONS: Diet and dietary components are potential tools to address various lifestyle-related disorders. Due to plenty of environmental and cellular toxicants, the chances of cancer prevalence are quite large which are worsen by adopting unhealthy lifestyles. Cancer can be treated with various therapies but those are acquiring side effects causing the patients to suffer the treatment regime. Nutraceuticals and functional foods provide safer options to prevent or delay the onset of cancer. In this regard, sulforaphane is a pivotal compound to be targeted as a potential agent for cancer treatment both in preventive and therapeutic regimes. This article provides sufficient evidence via discussing the underlying mechanisms of positive effects of sulforaphane to further the research for developing anticancer drugs that will help assuage this lethal morbidity.

Protective Effect of Isothiocyanates from Cruciferous Vegetables on Breast Cancer: Epidemiological and Preclinical Perspectives

BACKGROUND

The effect of cruciferous vegetable intake on breast cancer survival is controversial at present. Glucosinolates are the naturally occurring constituents found across the cruciferous vegetables. Isothiocyanates are produced from the hydrolysis of glucosinolates and this reaction is catalysed by the plant-derived enzyme myrosinase. The main Isothiocyanates (ITCs) from cruciferous vegetables are sulforaphane, benzyl ITC, and phenethyl ITC, which had been intensively investigated over the last decade for their anti-breast cancer effects.

OBJECTIVE

The aim of this article is to systematically review the evidence from all types of studies, which examined the protective effect of cruciferous vegetables and/or their isothiocyanate constituents on breast cancer.

METHODS

A systematic review was conducted in Pubmed, EMBASE, and the Cochrane Library from inception to 27 April 2020. Peer-reviewed studies of all types (in vitro studies, animal studies, and human studies) were selected.

RESULTS

The systematic literature search identified 16 human studies, 4 animal studies, and 65 in vitro studies. The effect of cruciferous vegetables and/or their ITCs intake on breast cancer survival was found to be controversial and varied greatly across human studies. Most of these trials were observational studies conducted in specific regions, mainly in the US and China. Substantial evidence from in vitro and animal studies was obtained, which strongly supported the protective effect of sulforaphane and other ITCs against breast cancer. Evidence from in vitro studies showed that sulforaphane and other ITCs reduced cancer cell viability and proliferation via multiple mechanisms and pathways. Isothiocyanates inhibited cell cycle, angiogenesis and epithelial mesenchymal transition, as well as induced apoptosis and altered the expression of phase II carcinogen detoxifying enzymes. These are the essential pathways that promote the growth and metastasis of breast cancer. Noticeably, benzyl ITC showed a significant inhibitory effect on breast cancer stem cells, a new dimension of chemo-resistance in breast cancer treatment. Sulforaphane and other ITCs displayed anti-breast cancer effects at variable range of concentrations and benzyl isothiocyanate appeared to have a relatively lower inhibitory concentration IC₅₀. The mechanisms underlying the cancer protective effect of sulforaphane and other ITCs have also been highlighted in this article.

CONCLUSION

Current preclinical evidence strongly supports the role of sulforaphane and other ITCs as potential therapeutic agents for breast cancer, either as adjunct therapy or combined therapy with current anti-breast cancer drugs, with sulforaphane displaying the greatest potential.

Dietary bioactive diindolylmethane enhances the therapeutic efficacy of centchroman in breast cancer cells by regulating ABCB1/P-gp efflux transporter

Overexpression of drug efflux transporters is commonly associated with multidrug-resistance in cancer therapy. Here for the first time, we investigated the ability of diindolylmethane (DIM), a dietary bioactive rich in cruciferous vegetables, in enhancing the efficacy of Centchroman (CC) by modulating the drug efflux transporters in human breast cancer cells. CC is a selective estrogen receptor modulator, having promising therapeutic efficacy against breast cancer. The combination of DIM and CC synergistically inhibited cell proliferation and induced apoptosis in breast cancer cells. This novel combination has also hindered the stemness of human breast cancer cells. Molecular docking analysis revealed that DIM had shown a strong binding affinity with the substrate-binding sites of ABCB1 (P-gp) and ABCC1 (MRP1) drug-efflux transporters. DIM has increased the intracellular accumulation of Hoechst and Calcein, the substrates of P-gp and MRP1, respectively, in breast cancer cells. Further, DIM stimulates P-gp ATPase activity, which indicates that DIM binds at the substrate-binding domain of P-gp, and thereby inhibits its efflux activity. Intriguingly, DIM enhanced the intracellular concentration of CC by inhibiting the P-gp and MRP1 expression as well as activity. The intracellular retaining of CC has increased its efficacy against breast cancer. Overall, DIM, a dietary bioactive, enhances the anticancer efficiency of CC through modulation of drug efflux ABC-transporters in breast cancer cells. Therefore, DIM-based nutraceuticals and functional foods can be developed as adjuvant therapy against human breast cancer.

Association between Oral Cancer and Diet: An Update

Oral cancer, included within head and neck cancer, is the sixth most common malignant neoplasm in the world. The main etiological factors are tobacco and alcohol, although currently, diet is considered an important determinant for its development. Several dietary nutrients have specific mechanisms of action, contributing to both protection against cancer and increasing the risk for development, growth, and spread. Foods such as fruits, vegetables, curcumin, and green tea can reduce the risk of oral cancer, while the so-called pro-inflammatory diet, rich in red meat and fried foods, can enhance the risk of occurrence. Dietary factors with a protective effect show different mechanisms that complement and overlap with antioxidant, anti-inflammatory, anti-angiogenic, and anti-proliferative effects. The main limitation of in vivo studies is the complexity of isolating the effects related to each one of the nutrients and the relationship with other possible etiological mechanisms. On the contrary, in vitro studies allow determining the specific mechanisms of action of some of the dietary compounds. In conclusion, and despite research limitations, the beneficial effects of a diet rich in vegetables and fruits are attributed to different micronutrients that are also found in fish and animal products. These compounds show antioxidant, anti-inflammatory, anti-angiogenic, and anti-proliferative properties that have a preventive role in the development of oral and other types of cancer.

Telomerase Regulation: A Role for Epigenetics

Simple Summary

Maintenance of telomeres is a fundamental step in human carcinogenesis and is primarily regulated by telomerase and the human telomerase reverse transcriptase gene (TERT). Improved understanding of the transcriptional control of this gene may provide potential therapeutic targets. Epigenetic modifications are a prominent mechanism to control telomerase activity and regulation of the TERT gene. TERT-targeting miRNAs have been widely studied and their function explained through pre-clinical in vivo model-based validation studies. Further, histone deacetylase inhibitors are now in pre and early clinical trials with significant clinical success. Importantly, TERT downregulation through epigenetic modifications including TERT promoter methylation, histone deacetylase inhibitors, and miRNA activity might contribute to clinical study design. This review provides an overview of the epigenetic mechanisms involved in the regulation of TERT expression and telomerase activity.

Abstract

Telomerase was first described by Greider and Blackburn in 1984, a discovery ultimately recognized by the Nobel Prize committee in 2009. The three decades following on from its discovery have been accompanied by an increased understanding of the fundamental mechanisms of telomerase activity, and its role in telomere biology. Telomerase has a clearly defined role in telomere length maintenance and an established influence on DNA replication, differentiation, survival, development, apoptosis, tumorigenesis, and a further role in therapeutic resistance in human stem and cancer cells including those of breast and cervical origin. TERT encodes the catalytic subunit and rate-limiting factor for telomerase enzyme activity. The mechanisms of activation or silencing of TERT remain open to debate across somatic, cancer, and stem cells. Promoter mutations upstream of TERT may promote dysregulated telomerase activation in tumour cells but additional factors including epigenetic, transcriptional and posttranscriptional modifications also have a role to play. Previous systematic analysis indicated methylation and mutation of the TERT promoter in 53% and 31%, respectively, of TERT expressing cancer cell lines supporting the concept of a key role for epigenetic alteration associated with TERT dysregulation and cellular transformation. Epigenetic regulators including DNA methylation, histone modification, and non-coding RNAs are now emerging as drivers in the regulation of telomeres and telomerase activity. Epigenetic regulation may be responsible for reversible silencing of TERT in several biological processes including development and differentiation, and increased TERT expression in cancers. Understanding the epigenetic mechanisms behind telomerase regulation holds important prospects for cancer treatment, diagnosis and prognosis. This review will focus on the role of epigenetics in telomerase regulation.

Lepidium sativum and Its Biogenic Silver Nanoparticles Activate Immune Cells and Induce Apoptosis and Cell Cycle Arrest in HT-29 Colon Cancer Cells

There is an increased demand for plants with antioxidants and anticancer properties. Lepidium sativum L. is an edible plant with medical importance. In this study, we aimed to investigate the anticancer activity; antioxidant capacity and antibacterial impact of Lepidium sativum L. seed acetone extract (LSSAExt), alone and with its biogenic silver nanoparticles (AgNPs). LSSAExt-produced AgNPs were characterized using SEM, XRD and Vis/UV analysis. Biomolecules in LSSAExt and LSSAExt + AgNPs were explored utilizing FTIR. The ability of LSSAExt and LSSAExt + AgNPs to induce apoptosis and mitotic cell arrest in the HT-29 colon cancer cells, compared to normal and repeated cell division activated splenic cells was determined by florescent stains and flow cytometry. Antibacterial power was tested using well diffusion technique. LSSAExt and LSSAExt + AgNPs showed a good antibacterial impact. LSSAExt contains ROS, which could help in cancer cells apoptosis. LSSAExt and LSSAExt+AgNPs were not toxic to splenic cells and increased the rate of their cell division. LSSAExt and LSSAExt+AgNPs increased p53 expression and could arrest cell division of HT-29 colon cancer cells but not of normal fast dividing cells. LSSAExt and LSSAExt+AgNPs caused apoptosis in cancer cells rather than necrosis. In conclusion, acetone preparation of the edible plant L. sativum is a good antibacterial agent, good anticancer preparation at least against colon cancer as it is shown to be targeted, effective and can boost immune cells.

Progress and promises of epigenetic drugs and epigenetic diets in cancer prevention and therapy: A clinical update

Epigenetic modifications are heritable yet reversible, essential for normal physiological functions and biological development. Aberrant epigenetic modifications, including DNA methylation, histone modification, and non-coding RNA (ncRNA)-mediated gene regulation play a crucial role in cancer progression. In cellular reprogramming, irregular epigenomic modulations alter cell signaling pathways and the expression of tumor suppressor genes and oncogenes, resulting in cancer growth and metastasis. Therefore, alteration of epigenetic-status in cancer cells can be used as a potential target for cancer therapy. Several synthetic epigenetic inhibitors (epi-drugs) and natural epigenetic modulatory bioactives (epi-diets) have been shown to have the potential to alter the aberrant epigenetic status and inhibit cancer progression. Further, the use of combinatorial approaches with epigenetic drugs and diets has brought promising outcomes in cancer prevention and therapy. In this article, we have summarized the epigenetic modulatory activities of epi-drugs, epi-diets, and their combination against various cancers. We have also compiled the preclinical and clinical status of these epigenetic modulators in different cancers.

Epigenetic modifications of c-MYC: Role in cancer cell reprogramming, progression and chemoresistance

Both genetic and epigenetic mechanisms intimately regulate cancer development and chemoresistance. Different genetic alterations are observed in multiple genes, and most are irreversible. Aside from genetic alterations, epigenetic alterations play a crucial role in cancer. The reversible nature of epigenetic modifications makes them an attractive target for cancer prevention and therapy. Specific epigenetic alteration is also being investigated as a potential biomarker in multiple cancers. c-MYC is one of the most important transcription factors that are centrally implicated in multiple types of cancer cells reprogramming, proliferation, and chemoresistance. c-MYC shows not only genetic alterations but epigenetic changes in multiple cancers. It has been observed that epigenome aberrations can reversibly alter the expression of c-MYC, both transcriptional and translational levels. Understanding the underlying mechanism of the epigenetic alterations of c-MYC, that has its role in multiple levels of cancer pathogenesis, can give a better understanding of various unresolved questions regarding cancer. Recently, some researchers reported that targeting the epigenetic modifiers of c-MYC can successfully inhibit cancer cell proliferation, sensitize the chemoresistant cells, and increase the patient survival rate. As c-MYC is an important transcription factor, epigenetic therapy might be one of the best alternatives for the conventional therapies that assumes the "one-size-fits-all" role. It can also increase the precision of targeting and enhance the effectiveness of treatments among various cancer subtypes. In this review, we highlighted the role of epigenetically modified c-MYC in cancer cell reprogramming, progression, and chemoresistance. We also summarize the potential therapeutic approaches to target these modifications for the prevention of cancer development and chemoresistant phenotypes.

Epigenetics/Epigenomics and Prevention of Early Stages of Cancer by Isothiocyanates

Cancer is a complex disease and cancer development takes 10-50 years involving epigenetics. Evidence suggests that approximately 80% of human cancers are linked to environmental factors impinging upon genetics/epigenetics. Because advanced metastasized cancers are resistant to radiotherapy/chemotherapeutic drugs, cancer prevention by relatively nontoxic chemopreventive "epigenetic modifiers" involving epigenetics/epigenomics is logical. Isothiocyanates are relatively nontoxic at low nutritional and even higher pharmacologic doses, with good oral bioavailability, potent antioxidative stress/antiinflammatory activities, possess epigenetic-modifying properties, great anticancer efficacy in many in vitro cell culture and in vivo animal models. This review summarizes the latest advances on the role of epigenetics/epigenomics by isothiocyanates in prevention of skin, colon, lung, breast, and prostate cancers. The exact molecular mechanism how isothiocyanates modify the epigenetic/epigenomic machinery is unclear. We postulate "redox" processes would play important roles. In addition, isothiocyanates sulforaphane and phenethyl isothiocyanate, possess multifaceted molecular mechanisms would be considered as "general" cancer preventive agents not unlike chemotherapeutic agents like platinum-based or taxane-based drugs. Analogous to chemotherapeutic agents, the isothiocyanates would need to be used in combination with other nontoxic chemopreventive phytochemicals or drugs such as NSAIDs, 5-α-reductase/aromatase inhibitors targeting different signaling pathways would be logical for the prevention of progression of tumors to late advanced metastatic states.

Sulforaphane in broccoli: The green chemoprevention!! Role in cancer prevention and therapy

Isothicyanates present in cruciferous vegetables are known to exhibit chemoprevention by various mechanisms. Presently, there is growing evidence that a phytochemical compound known as sulforaphane in these green leafy vegetables is found to be effective in preventing and treating various cancers such as prostate cancer, breast cancer, colon cancer, skin, urinary bladder and oral cancers. This component is naturally present in the broccoli sprouts, kale, cabbage, cauliflower and garden cress and is available as a commercial supplementary pill called Broccoli extract. Availability of many bioactive substances such as vitamins, polyphenols, sulfides, glucosinolates and antioxidants makes broccoli consumption important in daily diet regularly. Researchers have named it as "Green chemoprevention." It is easily affordable and more cost-effective than the traditional chemopreventive drugs. Results from the epidemiological and experimental studies have emphasized the role of sulforophane as a complementary or alternative chemopreventive agent.

Mechanisms Underlying Biological Effects of Cruciferous Glucosinolate-Derived Isothiocyanates/Indoles: A Focus on Metabolic Syndrome

An inverse correlation between vegetable consumption and the incidence of cancer has long been described. This protective effect is stronger when cruciferous vegetables are specifically consumed. The beneficial properties of vegetables are attributed to their bioactive components like fiber, antioxidants vitamins, antioxidants, minerals, and phenolic compounds. Cruciferous vegetables contain all these molecules; however, what makes them different are their sulfurous components, called glucosinolates, responsible for their special smell and taste. Glucosinolates are inactive biologically in the organism but are hydrolyzed by the enzyme myrosinase released as a result of chewing, leading to the formation of active derivatives such as isothiocyanates and indoles. A considerable number of in vitro and in vivo studies have reported that isothiocyanates and indoles elicit chemopreventive potency through multiple mechanisms that include modulation of phases I and II detoxification pathway enzymes, regulation of cell cycle arrest, and control of cell growth, induction of apoptosis, antioxidant activity, anti-angiogenic effects, and epigenetic regulation. Nuclear erythroid 2-related factor 2 (Nrf2) and Nuclear factor-κB (NF-κB) are key and central regulators in all these processes with a main role in oxidative stress and inflammation control. It has been described that isothiocyanates and indoles regulate their activity directly and indirectly. Today, the metabolic syndrome (central obesity, insulin resistance, hyperlipidemia, and hypertension) is responsible for a majority of deaths worldwide. All components of metabolic syndrome are characterized by chronic inflammation with deregulation of the PI3K/AKT/mTOR, MAPK/EKR/JNK, Nrf2, and NF-κB signaling pathways. The effects of GLSs derivatives controlling these pathways have been widely described in relation to cancer. Changes in food consumption patterns observed in the last decades to higher consumption of ultra-processed foods, with elevation in simple sugar and saturated fat contents and lower consumption of vegetables and fruits have been directly correlated with metabolic syndrome prevalence. In this review, it is summarized the knowledge regarding the mechanisms by which cruciferous glucosinolate derivatives (isothiocyanates and indoles) directly and indirectly regulate these pathways. However, the review places a special focus on the knowledge of the effects of glucosinolates derivatives in metabolic syndrome, since this has not been reviewed before.

The Impact of Natural Dietary Compounds and Food-Borne Mycotoxins on DNA Methylation and Cancer

Cancer initiation and progression is an accumulation of genetic and epigenetic modifications. DNA methylation is a common epigenetic modification that regulates gene expression, and aberrant DNA methylation patterns are considered a hallmark of cancer. The human diet is a source of micronutrients, bioactive molecules, and mycotoxins that have the ability to alter DNA methylation patterns and are thus a contributing factor for both the prevention and onset of cancer. Micronutrients such as betaine, choline, folate, and methionine serve as cofactors or methyl donors for one-carbon metabolism and other DNA methylation reactions. Dietary bioactive compounds such as curcumin, epigallocatechin-3-gallate, genistein, quercetin, resveratrol, and sulforaphane reactivate essential tumor suppressor genes by reversing aberrant DNA methylation patterns, and therefore, they have shown potential against various cancers. In contrast, fungi-contaminated agricultural foods are a source of potent mycotoxins that induce carcinogenesis. In this review, we summarize the existing literature on dietary micronutrients, bioactive compounds, and food-borne mycotoxins that affect DNA methylation patterns and identify their potential in the onset and treatment of cancer.

DNA Methylation Profiling of hTERT Gene Alongside with the Telomere Performance in Gastric Adenocarcinoma

PURPOSE

Epigenetic modification including of DNA methylation, histone acetylation, histone methylation, histon phosphorylation and non-coding RNA can impress the gene expression and genomic stability and cause different types of malignancies and also main human disorder. Conspicuously, the epigenetic alteration special DNA methylation controls telomere length, telomerase activity and also function of different genes particularly hTERT expression. Telomeres are important in increasing the lifespan, health, aging, and the development and progression of some diseases like cancer.

METHODS

This review provides an assessment of the epigenetic alterations of telomeres, telomerase and repression of its catalytic subunit, hTERT and function of long non-coding RNAs such as telomeric-repeat containing RNA (TERRA) in carcinogenesis and tumorgenesis of gastric cancer.

RESULTS

hTERT expression is essential and indispensable in telomerase activation through immortality and malignancies and also plays an important role in maintaining telomere length. Telomeres and telomerase have been implicated in regulating epigenetic factors influencing certain gene expression. Correspondingly, these changes in the sub telomere and telomere regions are affected by the shortening of telomere length and increased telomerase activity and hTERT gene expression have been observed in many cancers, remarkably in gastric cancer.

CONCLUSION

Epigenetic alteration and regulation of hTERT gene expression are critical in controlling telomerase activity and its expression. Graphical Abstract.