Muscadine Grape Skin Extract (MPX) in Men with Biochemically Recurrent Prostate Cancer: A Randomized, Multicenter, Placebo-Controlled Clinical Trial

Unveiling the potential of Muscadine grape Skin extract as an innovative therapeutic intervention in cancer treatment

The use of muscadine grape extracts (MGSE). in cancer treatment has gained attention due to its distinctive composition of polyphenols and antioxidants. This review analyses the reported anti-cancer properties of MGSE. The study commences by reviewing the phytochemical composition of MGSE, highlighting the presence of resveratrol and ellagic acid. Furthermore, the review underscores the mechanism of action of these active compounds in MGSE in combating cancer cells. The anti-cancer potential of MGSE compared to other plant extracts is also discussed. In addition, it highlights MGSE's superiority and distinct phytochemical composition in preventing cancer growth by comparing its anti-cancer compounds with those of other anti-cancer medicinal plants. Lastly, the combinatory approaches of MGSE with traditional cancer therapies, its safety, and its possible side effects were highlighted. This work provides an understanding of the anti-cancer properties of MGSE, positioning it as a valuable and unique challenge within the field of cancer therapy.

Inhibitory Potential of Resveratrol in Cancer Metastasis: From Biology to Therapy

Cancer metastasis is a significant challenge in cancer treatment, and most existing drugs are designed to inhibit tumor growth but are often ineffective in treating metastatic cancer, which is the leading cause of cancer-related deaths. Resveratrol, a polyphenol found in grapes, berries, and peanuts, has shown potential in preclinical studies as an anticancer agent to suppress metastasis. However, despite positive results in preclinical studies, little progress has been made in clinical trials. To develop resveratrol as an effective anticancer agent, it is crucial to understand its cellular processes and signaling pathways in tumor metastasis. This review article evaluates the current state and future development strategies of resveratrol to enhance its potency against cancer metastasis within its therapeutic dose. In addition, we critically evaluate the animal models used in preclinical studies for cancer metastasis and discuss novel techniques to accelerate the translation of resveratrol from bench to bedside. The appropriate selection of animal models is vital in determining whether resveratrol can be further developed as an antimetastatic drug in cancer therapy.

Phytochemicals in Cancer Treatment and Cancer Prevention-Review on Epidemiological Data and Clinical Trials

Phytochemicals are a non-nutritive substances that are present in plants and contribute significantly to their flavor and color. These biologically active compounds are classified into five major groups, namely phenolics, carotenoids, organosulfur compounds, nitrogen-containing compounds, and alkaloids, and are known for their potential health benefits in the prevention of various diseases, including cancer. The purpose of this review article is to explore the potential therapeutic benefits of the dietary phytochemicals, such as flavonoids, phenolic acids, phytosterols, carotenoids, and stilbenes, in cancer treatment and prevention based on the epidemiological studies and clinical trials. Although the majority of epidemiological studies report a significant advantage of the heightened phytochemical consumption and increased serum levels of these compounds, linking increased exposure with a lower cancer risk across most cancer types, these effects could not be replicated in the most available clinical trials. In fact, many of these trials were withdrawn early due to a lack of evidence and/or risk of harm. Despite the strong anticancer effect of phytochemicals, as well as their proven efficacy in multiple epidemiological studies, there is still a great need for human studies and clinical trials, with great caution regarding the safety measures. This review article provides an overview of the epidemiological and clinical evidence supporting the potential chemopreventive and anticancer properties of phytochemicals, with a focus on the need for further research in this area.

Uncovering the mechanism of Kang-ai injection for treating intrahepatic cholangiocarcinoma based on network pharmacology, molecular docking, and in vitro validation

Objective: Kang-ai injection (KAI) has been a popular adjuvant treatment for solid tumors, but its anti-tumor mechanism in intrahepatic cholangiocarcinoma (ICC) remains poorly understood. This study applied a network pharmacology-based approach to unveil KAI's anti-tumor activity, key targets, and potential pharmacological mechanism in ICC by integrating molecular docking and in vitro validation. Methods: The KAI-compound-target-ICC network was constructed to depict the connections between active KAI compounds and ICC-related targets based on the available data sources. The crucial ingredients, potential targets, and signaling pathways were screened using GO, KEGG enrichment analysis, and the PPI network. Molecular docking was performed to visualize the interactions between hub targets and components. In vitro experiments were carried out to validate the findings. Results: Among the 87 active components of KAI and 80 KAI-ICC-related targets, bioinformatics analysis identified quercetin as a possible candidate. GO and KEGG enrichment analysis indicated that the PI3K-AKT signaling pathway might be essential in ICC pharmacotherapy. The PPI network and its sub-networks screened 10 core target genes, including AKT1 and IL1β. Molecular docking results showed stable binding between AKT1 and IL1β with KAI active ingredients. The in vitro experiments confirmed that KAI might suppress the proliferation of ICC cell lines by inhibiting the PI3K/AKT signaling pathway, consistent with the network pharmacology approach and molecular docking predictions. Conclusion: The study sheds light on KAI's biological activity, potential targets, and molecular mechanisms in treating ICC and provides a promising strategy for understanding the scientific basis and therapeutic mechanisms of herbal treatments for ICC. This research has important implications for developing new, targeted therapies for ICC and highlights the importance of network pharmacology-based approaches in investigating complex herbal formulations.

Analytical Validation of SOD2 Genotyping

Manganese superoxide dismutase-2 (SOD2) plays a crucial role in cells' protection against mitochondrial oxidative damage. A genetic polymorphism in the mitochondrial targeting sequence of the SOD2 gene has been implicated in various diseases, including prostate cancer. Paller et al. have shown an increase in prostate-specific antigen (PSA) doubling time in patients with the Ala/Ala (wildtype) genotype when treated with pomegranate/grape extract antioxidants. We developed and validated a pyrosequencing assay that detects the common germline SOD2 SNP (rs_4880) with the aim of identifying men with castrate-resistant prostate cancer eligible for an antioxidant therapy clinical trial. We first selected 37 samples from the 1000 genomes study with known genotypes determined using Illumina-based sequencing and confirmed them by Sanger sequencing. In a blinded design, we then performed the new pyrosequencing assay on these samples and assigned genotypes. Genotypes for all 37 samples (13 homozygous Ala, 12 heterozygous Ala/Val, and 12 homozygous Val) were all concordant by pyrosequencing. The pyrosequencing assay has been live since May 2018 and has proven to be robust and accurate.

Exploiting Polyphenol-Mediated Redox Reorientation in Cancer Therapy

Polyphenol, one of the major components that exert the therapeutic effect of Chinese herbal medicine (CHM), comprises several categories, including flavonoids, phenolic acids, lignans and stilbenes, and has long been studied in oncology due to its significant efficacy against cancers in vitro and in vivo. Recent evidence has linked this antitumor activity to the role of polyphenols in the modulation of redox homeostasis (e.g., pro/antioxidative effect) in cancer cells. Dysregulation of redox homeostasis could lead to the overproduction of reactive oxygen species (ROS), resulting in oxidative stress, which is essential for many aspects of tumors, such as tumorigenesis, progression, and drug resistance. Thus, investigating the ROS-mediated anticancer properties of polyphenols is beneficial for the discovery and development of novel pharmacologic agents. In this review, we summarized these extensively studied polyphenols and discussed the regulatory mechanisms related to the modulation of redox homeostasis that are involved in their antitumor property. In addition, we discussed novel technologies and strategies that could promote the development of CHM-derived polyphenols to improve their versatile anticancer properties, including the development of novel delivery systems, chemical modification, and combination with other agents.

Destroying the Shield of Cancer Stem Cells: Natural Compounds as Promising Players in Cancer Therapy

In a scenario where eco-sustainability and a reduction in chemotherapeutic drug waste are certainly a prerogative to safeguard the biosphere, the use of natural products (NPs) represents an alternative therapeutic approach to counteract cancer diseases. The presence of a heterogeneous cancer stem cell (CSC) population within a tumor bulk is related to disease recurrence and therapy resistance. For this reason, CSC targeting presents a promising strategy for hampering cancer recurrence. Increasing evidence shows that NPs can inhibit crucial signaling pathways involved in the maintenance of CSC stemness and sensitize CSCs to standard chemotherapeutic treatments. Moreover, their limited toxicity and low costs for large-scale production could accelerate the use of NPs in clinical settings. In this review, we will summarize the most relevant studies regarding the effects of NPs derived from major natural sources, e.g., food, botanical, and marine species, on CSCs, elucidating their use in pre-clinical and clinical studies.

Targeted UHPLC-MS Analysis Reveals Disparate Polyphenol Composition and Concentration in Muscadine Grape Supplements with Proportional Antioxidant Activity

Muscadine grape supplements (MGS) with high polyphenol content are a potential therapeutic option to combat oxidative stress; however, the precise identity and concentration of individual phenolics in commercially processed MGSs is not well defined. We probed for 17 phenolic compounds by ultra-high pressure liquid chromatography and mass spectroscopy from distinct lots of four commercially processed MGSs composed of MG seed and/or skin waste products. The total phenolic content (TPC) and antioxidant capacity were highest in a dried water-extract MGS as compared to three ground seed and/or skin products. The TPC was not different between MGS lots from individual companies and remained stable for 3 years without microbial contamination. The extract MGS had the highest concentration of epicatechin, ellagic acid, gallic acid, procyanidin B2, catechin and catechin gallate compared to the other supplements. Only ellagic acid and gallic acid were detected in all four MGSs, while catechin and catechin gallate were below detection in two supplements. Based on gram weight, only the extract MGS prevented the angiotensin II-induced increase in malondialdehyde and 4-hydroxynonenol in rat H9c2 cardiomyocytes as well as upregulated superoxide dismutase and catalase. This study demonstrates that commercial MGSs differ in phenolic composition and concentration, resulting in disparate antioxidant activity.

A Polyphenol-Rich Extract from Muscadine Grapes Prevents Hypertension-Induced Diastolic Dysfunction and Oxidative Stress

Muscadine grapes are abundant in dietary polyphenols, but their effect on hypertension-induced cardiac damage is limited. This study assessed whether a muscadine grape skin/seed extract supplement (MGES) prevents hypertension-induced cardiac damage and oxidative stress. Male Sprague Dawley rats were treated for four weeks with drinking water, angiotensin II (Ang II) to induce hypertension, MGES, or both Ang II and MGES. Cardiac function assessed by echocardiography showed that Ang II increased systolic blood pressure while MGES alone or in combination with Ang II had no effect. Ang II increased E/e', an indicator of left ventricular filling pressure and diastolic dysfunction, by 41% compared to Control and co-treatment with MGES prevented the Ang II-mediated increase, suggesting that the extract attenuated hypertension-induced diastolic function. Ang II infusion increased urinary 8-hydroxy-2'-deoxyguanosine and cardiac 4-hydroxynonenal and malondialdehyde, which were prevented by the extract. The antioxidant enzymes catalase and superoxide dismutase 1 activity and mRNA were increased significantly in animals treated with MGES alone or in combination with Ang II, suggesting that the extract upregulates oxidative stress defense mechanisms in cardiac tissue. Thus, MGES may serve as a medical food to protect the heart from hypertension-induced diastolic dysfunction caused in part by excessive reactive oxygen species production.

Natural Radiosensitizers in Radiotherapy: Cancer Treatment by Combining Ionizing Radiation with Resveratrol

Conventional cancer treatment is mainly based on the surgical removal of the tumor followed by radiotherapy and/or chemotherapy. When surgical removal is not possible, radiotherapy and, less often, chemotherapy is the only way to treat patients. However, despite significant progress in understanding the molecular mechanisms of carcinogenesis and developments in modern radiotherapy techniques, radiotherapy (alone or in combination) does not always guarantee treatment success. One of the main causes is the radioresistance of cancer cells. Increasing the radiosensitivity of cancer cells improves the processes leading to their elimination during radiotherapy and prolonging the survival of cancer patients. In order to enhance the effect of radiotherapy in the treatment of radioresistant neoplasms, radiosensitizers are used. In clinical practice, synthetic radiosensitizers are commonly applied, but scientists have recently focused on using natural products (phytocompounds) as adjuvants in radiotherapy. In this review article, we only discuss naturally occurring radiosensitizers currently in clinical trials (paclitaxel, curcumin, genistein, and papaverine) and those whose radiation sensitizing effects, such as resveratrol, have been repeatedly confirmed by many independent studies.

Anti-prostate cancer protection and therapy in the framework of predictive, preventive and personalised medicine — comprehensive effects of phytochemicals in primary, secondary and tertiary care

According to the GLOBOCAN 2020, prostate cancer (PCa) is the most often diagnosed male cancer in 112 countries and the leading cancer-related death in 48 countries. Moreover, PCa incidence permanently increases in adolescents and young adults. Also, the rates of metastasising PCa continuously grow up in young populations. Corresponding socio-economic burden is enormous: PCa treatment costs increase more rapidly than for any other cancer. In order to reverse current trends in exploding PCa cases and treatment costs, pragmatic decisions should be made, in favour of advanced populational screening programmes and effective anti-PCa protection at the level of the health-to-disease transition (sub-optimal health conditions) demonstrating the highest cost-efficacy of treatments. For doing this, the paradigm change from reactive treatments of the clinically manifested PCa to the predictive approach and personalised prevention is essential.

Phytochemicals are associated with potent anti-cancer activity targeting each stage of carcinogenesis including cell apoptosis and proliferation, cancer invasiveness and metastatic disease. For example, their positive effects are demonstrated for stabilising and restoring mitochondrial health quality, which if compromised is strongly associated with sub-optimal health conditions and strong predisposition to aggressive PCa sub-types. Further, phytochemicals significantly enhance response of cancer cells to anti-cancer therapies including radio- and chemotherapy. Evident plant-based mitigation of negative side-effects frequently observed for conventional anti-cancer therapies has been reported. Finally, dual anti-cancer and anti-viral effects of phytochemicals such as these of silibinin have been demonstrated as being highly relevant for improved PCa management at the level of secondary and tertiary care, for example, under pandemic conditions, since PCa-affected individuals per evidence are highly vulnerable towards COVID-19 infection.

Here, we present a comprehensive data analysis towards clinically relevant anti-cancer effects of phytochemicals to be considered for personalised anti-PCa protection in primary care as well as for an advanced disease management at the level of secondary and tertiary care in the framework of predictive, preventive and personalised medicine.

Harnessing redox signaling to overcome therapeutic-resistant cancer dormancy

Dormancy occurs when cells preserve viability but stop proliferating, which is considered an important cause of tumor relapse, which may occur many years after clinical remission. Since the life cycle of dormant cancer cells is affected by both intracellular and extracellular factors, gene mutation or epigenetic regulation of tumor cells may not fully explain the mechanisms involved. Recent studies have indicated that redox signaling regulates the formation, maintenance, and reactivation of dormant cancer cells by modulating intracellular signaling pathways and the extracellular environment, which provides a molecular explanation for the life cycle of dormant tumor cells. Indeed, redox signaling regulates the onset of dormancy by balancing the intrinsic pathways, the extrinsic environment, and the response to therapy. In addition, redox signaling sustains dormancy by managing stress homeostasis, maintaining stemness and immunogenic equilibrium. However, studies on dormancy reactivation are still limited, partly explained by redox-mediated activation of lipid metabolism and the transition from the tumor microenvironment to inflammation. Encouragingly, several drug combination strategies based on redox biology are currently under clinical evaluation. Continuing to gain an in-depth understanding of redox regulation and develop specific methods targeting redox modification holds the promise to accelerate the development of strategies to treat dormant tumors and benefit cancer patients.

Angioprevention of Urologic Cancers by Plant-Derived Foods

The number of cancer cases worldwide keeps growing unstoppably, despite the undeniable advances achieved by basic research and clinical practice. Urologic tumors, including some as prevalent as prostate, bladder or kidney tumors, are no exceptions to this rule. Moreover, the fact that many of these tumors are detected in early stages lengthens the duration of their treatment, with a significant increase in health care costs. In this scenario, prevention offers the most cost-effective long-term strategy for the global control of these diseases. Although specialized diets are not the only way to decrease the chances to develop cancer, epidemiological evidence support the role of certain plant-derived foods in the prevention of urologic cancer. In many cases, these plants are rich in antiangiogenic phytochemicals, which could be responsible for their protective or angiopreventive properties. Angiogenesis inhibition may contribute to slow down the progression of the tumor at very different stages and, for this reason, angiopreventive strategies could be implemented at different levels of chemoprevention, depending on the targeted population. In this review, epidemiological evidence supporting the role of certain plant-derived foods in urologic cancer prevention are presented, with particular emphasis on their content in bioactive phytochemicals that could be used in the angioprevention of cancer.

Prostate cancer: Therapeutic prospect with herbal medicine

Prostate cancer (PCa) is a major cause of morbidity and mortality in men worldwide. A geographic variation on the burden of the disease suggested that the environment, genetic makeup, lifestyle, and food habits modulate one's susceptibility to the disease. Although it has been generally thought to be an older age disease, and awareness and timely execution of screening programs have managed to contain the disease in the older population over the last decades, the incidence is still increasing in the population younger than 50. Existing treatment is efficient for PCa that is localized and responsive to androgen. However, the androgen resistant and metastatic PCa are challenging to treat. Conventional radiation and chemotherapies are associated with severe side effects in addition to being exorbitantly expensive. Many isolated phytochemicals and extracts of plants used in traditional medicine are known for their safety and diverse healing properties, including many with varying levels of anti-PCa activities. Many of the phytochemicals discussed here, as shown by many laboratories, inhibit tumor cell growth and proliferation by interfering with the components in the pathways responsible for the enhanced proliferation, metabolism, angiogenesis, invasion, and metastasis in the prostate cells while upregulating the mechanisms of cell death and cell cycle arrest. Notably, many of these agents simultaneously target multiple cellular pathways. We analyzed the available literature and provided an update on this issue in this review article.

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Prostate cancer in a major cause of death in older population worldwide.

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Efficacies of current treatment options are limited in many cases.

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Phytochemicals and extracts isolated from plants show anti-prostate cancer activity with unique mechanisms.

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Certain phytochemicals alone or in combination with current chemotherapy show therapeutic promise.

Natural Product-Based Studies for the Management of Castration-Resistant Prostate Cancer: Computational to Clinical Studies

Background: With prostate cancer being the fifth-greatest cause of cancer mortality in 2020, there is a dire need to expand the available treatment options. Castration-resistant prostate cancer (CRPC) progresses despite androgen depletion therapy. The mechanisms of resistance are yet to be fully discovered. However, it is hypothesized that androgens depletion enables androgen-independent cells to proliferate and recolonize the tumor. Objectives: Natural bioactive compounds from edible plants and herbal remedies might potentially address this need. This review compiles the available cheminformatics-based studies and the translational studies regarding the use of natural products to manage CRPC. Methods: PubMed and Google Scholar searches for preclinical studies were performed, while ClinicalTrials.gov and PubMed were searched for clinical updates. Studies that were not in English and not available as full text were excluded. The period of literature covered was from 1985 to the present. Results and Conclusion: Our analysis suggested that natural compounds exert beneficial effects due to their broad-spectrum molecular disease-associated targets. In vitro and in vivo studies revealed several bioactive compounds, including rutaecarpine, berberine, curcumin, other flavonoids, pentacyclic triterpenoids, and steroid-based phytochemicals. Molecular modeling tools, including machine and deep learning, have made the analysis more comprehensive. Preclinical and clinical studies on resveratrol, soy isoflavone, lycopene, quercetin, and gossypol have further validated the translational potential of the natural products in the management of prostate cancer.

Resveratrol for cancer therapy: Challenges and future perspectives

Resveratrol (3,4',5-trihydroxy-trans-stilbene) has been expected to ameliorate cancer and foster breakthroughs in cancer therapy. Despite thousands of preclinical studies on the anticancer activity of resveratrol, little progress has been made in translational research and clinical trials. Most studies have focused on its anticancer effects, cellular mechanisms, and signal transduction pathways in vitro and in vivo. In this review, we aimed to discern the causes that prevent resveratrol from being used in cancer treatment. Among the various limitations, poor pharmacokinetics and low potency seem to be the two main bottlenecks of resveratrol. In addition, resveratrol-induced nephrotoxicity in multiple myeloma patients hinders its further development as an anticancer drug. New insights and strategies have been proposed to accelerate the conversion of resveratrol from bench to bedside. In the interim, the most promising approach is to enhance the bioavailability of resveratrol with new formulations. Alternatively, more potent analogues of resveratrol could be developed to augment its anticancer potency. Given all the gaps mentioned, much work remains to be done. However, if remarkable progress can be made, resveratrol may finally be used for cancer therapy.

Pharmacological Properties of Polyphenols: Bioavailability, Mechanisms of Action, and Biological Effects in In Vitro Studies, Animal Models, and Humans

Drugs are bioactive compounds originally discovered from chemical structures present in both the plant and animal kingdoms. These have the ability to interact with molecules found in our body, blocking them, activating them, or increasing or decreasing their levels. Their actions have allowed us to cure diseases and improve our state of health, which has led us to increase the longevity of our species. Among the molecules with pharmacological activity produced by plants are the polyphenols. These, due to their molecular structure, as drugs, also have the ability to interact with molecules in our body, presenting various pharmacological properties. In addition, these compounds are found in multiple foods in our diet. In this review, we focused on discussing the bioavailability of these compounds when we ingested them through diet and the specific mechanisms of action of polyphenols, focusing on studies carried out in vitro, in animals and in humans over the last five years. Knowing which foods have these pharmacological activities could allow us to prevent and aid as concomitant treatment against various pathologies.

Phase I Study of Muscadine Grape Extract for Patients With Advanced Cancer

OBJECTIVE

Preclinical studies with muscadine grape extract (MGE) show antitumor activity and decreased systemic inflammation. This phase I study (NCT02583269) assessed safety and tolerability of a proprietary MGE preparation in patients with advanced solid tumors.

METHODS

Patients with metastatic or unresectable cancers who were progressing on standard therapies were assigned to MGE in a standard 3+3 design. Five dose levels were tested (320 to 1600 mg total phenolics/d). Safety and maximum-tolerated dose were assessed after 4 weeks. Patients were evaluated for response at 8 weeks and continued on MGE if clinically stable. Secondary outcomes were response, survival, adherence, fatigue, and quality of life (QOL).

RESULTS

In total, 23 patients (lung, n=7; gastrointestinal, n=7; genitourinary, n=6; other, n=3) received MGE capsules by mouth twice daily. The cohort [median age 72 years, 48% Eastern Cooperative Oncology Group (ECOG) 2] was heavily pretreated. After 4 weeks on MGE, possibly attributable adverse events grade 2 or higher were fatigue (n=1), decreased lymphocyte count (n=1), and constipation (n=2), including 1 dose-limiting toxicity for grade 3 constipation. Maximum-tolerated dose was not reached. No partial responses were observed. Median time on therapy was 8 weeks, with 29% of patients treated beyond 16 weeks and a median overall survival of 7.2 months. QOL and fatigue levels were stable from baseline to 8 weeks. Higher MGE dose was correlated with improvement in self-reported physical well-being QOL at 8 weeks (r=0.6; P=0.04).

CONCLUSIONS

MGE is safe and well-tolerated in heavily pretreated and older cancer patients.  The potential anticancer properties and the effects of MGE on physical well-being and QOL metrics will be evaluated in future studies.

The effect of grape products containing polyphenols on oxidative stress: a systematic review and meta-analysis of randomized clinical trials

BACKGROUND

The literature showed that Grape Products Containing Polyphenols (GPCP) had anti-oxidant activity. However, the effects of GPCP on different biomarkers of oxidative stress are still controversial. In this regard, this systematic review and meta-analysis aimed to evaluate the effect of Grape Products Containing Polyphenols (GPCP) intake on oxidative stress markers.

METHODS

PubMed, Scopus, Web of Science, and Google Scholar data bases were searched up to August 20, 2020. A random-effects model, weighted mean difference (WMD), and 95% confidence interval (CI) were applied for data analysis. Meta-analysis was conducted over 17 eligible RCTs with a total of 633 participants. The study registration number is CRD42019116696.

RESULTS

A significant increase was observed in Total Antioxidant Capacity (TAC) (weighted mean difference (WMD) = 1.524 mmol/L, 95% confidence interval (CI): 0.83, 2.21). Intake of GPCP enhanced Superoxide Dismutase (SOD) (WMD = 0.450 mmol/L, 95% CI: 0.23, 0.66), TAC (WMD = 2.829 mmol/L, 95% CI: 0.13, 5.52), and Oxygen Radical Absorbance Capacity (ORAC) (WMD = 0.524 μmol/L, 95% CI: 0.42, 0.62) among healthy participants. Higher GPCP doses increased SOD (WMD = 0.539 U/mgHb, 95% CI: 0.24, 0.82) and ORAC (WMD = 0.377 μmol/L, 95% CI: 0.08, 0.67), whereas longer intervention periods enhanced ORAC (WMD = 0.543 μmol/L, 95% CI: 0.43, 0.64).

CONCLUSION

GPCP intake may partly improve status of oxidative stress, but further well-designed trials are required to confirm these results.

Status and Challenges of Plant-Anticancer Compounds in Cancer Treatment

Nowadays, cancer is one of the deadliest diseases in the world, which has been estimated to cause 9.9 million deaths in 2020. Conventional treatments for cancer commonly involve mono-chemotherapy or a combination of radiotherapy and mono-chemotherapy. However, the negative side effects of these approaches have been extensively reported and have prompted the search of new therapeutic drugs. In this context, scientific community started to look for innovative sources of anticancer compounds in natural sources, including traditional plants. Currently, numerous studies have evaluated the anticancer properties of natural compounds derived from plants, both in vitro and in vivo. In pre-clinical stages, some promising compounds could be mentioned, such as the sulforaphane or different phenolic compounds. On the other hand, some phytochemicals obtained positive results in clinical stages and were further approved for cancer treatment, such as vinca alkaloids or the paclitaxel. Nevertheless, these compounds are not exempt of limitations, such as low solubility, restricted effect on their own, negative side-effects, etc. This review aims to compile the information about the current phytochemicals used for cancer treatment and also promising candidates, main action mechanisms and also reported limitations. In this sense, some strategies to face the limitations have been considered, such as nano-based formulations to improve solubility or chemical modification to reduce toxicity. In conclusion, although more research is still necessary to develop more efficient and safe phytochemical drugs, more of these compounds might be used in future cancer therapies.

Val16A SOD2 Polymorphism Promotes Epithelial-Mesenchymal Transition Antagonized by Muscadine Grape Skin Extract in Prostate Cancer Cells

Epithelial–mesenchymal transition (EMT), a key event in cancer metastasis, allows polarized epithelial cells to assume mesenchymal morphologies, enhancing invasiveness and migration, and can be induced by reactive oxygen species (ROS). Val16A (Ala) SOD2 polymorphism has been associated with increased prostate cancer (PCa) risk. We hypothesized that SOD2 Ala single nucleotide polymorphism (SNP) may promote EMT. We analyzed SOD2 expression and genotype in various prostate cell lines. Stable overexpression of Ala-SOD2 or Val-SOD2 allele was performed in Lymph Node Carcinoma of the Prostate (LNCaP) cells followed by analysis of intracellular ROS and EMT marker protein expression. Treatments were performed with muscadine grape skin extract (MSKE) antioxidant, with or without addition of H₂O₂ to provide further oxidative stress. Furthermore, MTS cell proliferation, cell migration, and apoptosis assays were completed. The results showed that SOD2 expression did not correlate with tumor aggressiveness nor SOD2 genotype. We demonstrated that the Ala-SOD2 allele was associated with marked induction of EMT indicated by higher Snail and vimentin, lower E-cadherin, and increased cell migration, when compared to Val-SOD2 allele or Neo control cells. Ala-SOD2 SNP cells exhibited increased levels of total ROS and superoxide and were more sensitive to co-treatment with H₂O₂ and MSKE, which led to reduced cell growth and increased apoptosis. Additionally, MSKE inhibited Ala-SOD2 SNP-mediated EMT. Our data indicates that treatment with a combination of H₂O₂-generative drugs, such as certain chemotherapeutics and antioxidants such as MSKE that targets superoxide, hold promising therapeutic potential to halt PCa progression in the future.

A phase II randomized placebo-controlled trial of pomegranate fruit extract in men with localized prostate cancer undergoing active surveillance

INTRODUCTION OR OBJECTIVE

Men with favorable-risk prostate cancer (PCa) on active surveillance may benefit from intervention strategies to slow or prevent disease progression and the need for definitive treatment. Pomegranate and its extracts have shown antiproliferative and proapoptotic effects in cell lines and animal models, but its effect on human prostate cancer as a target tissue remain unclear. Objectives of this trial include pomegranate's ability to alter serum and prostate tissue biomarkers and the ability of an active surveillance cohort to adhere to a chemoprevention trial for 1 year.

METHODS

Men with organ-confined, favorable-risk PCa on AS were randomly assigned to receive pomegranate fruit extract (PFE) 1000 mg (n = 15) or placebo (n = 15) once daily for twelve months. Prostate biopsies were performed at study entry and upon completion of the 1-year intervention. Plasma and urinary biomarkers were analyzed utilizing immunoassays and HPLC. Tissue proteins were assessed by immunohistochemistry (IHC) and measured by automated quantitation.

RESULTS

PFE was well-tolerated with no significant toxicities. One patient withdrew before study initiation and 29 completed the 1-year intervention. No differences in plasma insulin-like growth factor-1 (IGF-1) levels, prostate-specific antigen doubling time, or biopsy kinetics were observed. Metabolites including urolithin A and urolithin A-gluc were detected more frequently in the PFE arm in both urine and plasma (p < .001 and p = .006, respectively). IHC analyses revealed reductions from baseline in 8-OHdG (a DNA damage marker) (p = .01) and androgen receptor expression (p = .04) in prostate tumor associated with PFE treatment.

CONCLUSION

PFE administration for 12-month was well-tolerated and the protocol followed in an active surveillance population. Analyses suggest that PFE contains bioactive compounds capable of altering biomarkers involving oxidative stress and androgen signaling in prostate tumor and normal-appearing adjacent tissue. No alterations in the IGF axis were noted. This finding of study adherence and target activity provides a rationale for the further investigation of PFE in the active surveillance population.

Brazilian berry extract (Myrciaria jaboticaba): A promising therapy to minimize prostatic inflammation and oxidative stress

BACKGROUND

Brazilian berry is a fruit popularly known as "Jaboticaba," rich in bioactive compounds with antioxidant and anti-inflammatory properties. Senescence and overweight are increasing worldwide and are considered risk factors to prostatic pathogenesis mainly due to oxidative and inflammatory processes induction. Thus, this study aimed to evaluate the effect of two increasing doses of the patented jaboticaba peel extract (PJE) on oxidative-stress and inflammation in the prostate of aging or high-fat-fed aging mice.

METHODS

PJE and/or high-fat diet (HFD) treatments started with 11-month-old mice and lasted 60 days. The levels or the immunoexpression of different inflammatory (nuclear factor κB [NFκB], CD3+, cyclooxygenase 2 [COX-2], toll-like receptor 4 [TLR4], phosphorylated signal transducers and activators of transcription 3 [pSTAT-3], tumor necrosis factor α [TNF-α], interleukin 6 [IL-6], and IL-1β) and oxidative-stress (catalase, superoxide dismutase 2 [SOD2], glutathione reductase [GSR], reduced glutathione, and glutathione peroxidase 3 [GPx3]) related molecules were analyzed by western-blotting, immunohistochemistry, and enzyme-linked immunosorbent assays.

RESULTS

Both PJE doses reduced the levels of oxidative-stress-related molecules (GPx3, GSR, catalase), lipid peroxidation (4-hydroxynonenal), inflammatory mediators (COX-2, TNF-α, and pSTAT-3) and CD3+ T cells number, which were associated with the maintenance of the glandular morphological integrity in aging and HFD-fed-aging mice. Nevertheless, only the high PJE dose reduced the NFκB and TLR4 levels in aging mice; and SOD2, IL-6, and IL-1β levels in HFD-aging mice. Aging itself promoted an oxidative inflammation in the prostate, interfering in the levels of the different oxidative-stress, lipid peroxidation, and inflammatory mediators evaluated, in association with high incidence of prostate epithelial and stromal damages. The HFD intake intensified aging alterations, showing an unfavorable prostatic microenvironment prone to oxidative and inflammatory damages.

CONCLUSIONS

PJE exerted a dose-dependent effect controlling inflammation and oxidative-stress in aging and HFD-fed aging mice prostate. This fact contributed to prostate microenvironment balance recovery, preserving the tissue architecture of this gland. Thus, the PJE emerges as a potential therapy to prevent inflammation and oxidative stress in the prostate.

Grape Powder Supplementation Attenuates Prostate Neoplasia Associated with Pten Haploinsufficiency in Mice Fed High-Fat Diet

SCOPE

Previous studies have identified potent anticancer activities of polyphenols in preventing prostate cancer. The aim of the current study is to evaluate the chemopreventive potential of grape powder (GP) supplemented diets in genetically predisposed and obesity-provoked prostate cancer.

METHODS AND RESULTS

Prostate-specific Pten heterozygous (Pten+/f ) transgenic mice are fed low- and high-fat diet (LFD and HFD, respectively) supplemented with 10% GP for 33 weeks, ad libitum. Prostate tissues are characterized using immunohistochemistry and western blots, and sera are analyzed by ELISA and qRT-PCR. Pten+/f mice fed LFD and HFD supplemented with 10% GP show favorable histopathology, significant reduction of the proliferative rate of prostate epithelial cells (Ki67), and rescue of PTEN expression. The most potent protective effect of GP supplementation is detected against HFD-induced increase in inflammation (IL-1β; TGF-β1), activation of cell survival pathways (Akt, AR), and angiogenesis (CD31) in Pten+/f mice. Moreover, GP supplementation reduces circulating levels of oncogenic microRNAs (miR-34a; miR-22) in Pten+/f mice. There are no significant changes in body weight and food intake in GP supplemented diet groups.

CONCLUSIONS

GP diet supplementation can be a beneficial chemopreventive strategy for obesity-related inflammation and prostate cancer progression. Monitoring serum miRNAs can facilitate the non-invasive evaluation of chemoprevention efficacy.

NF-κB signaling promotes castration-resistant prostate cancer initiation and progression

Prostate Cancer (PCa) is the second leading cause of cancer-related death in men. Adenocarcinoma of the prostate is primarily composed of Androgen Receptor-positive (AR⁺) luminal cells that require AR transcriptional activity for survival and proliferation. As a consequence, androgen deprivation and anti-androgens are used to treat PCa patients whose disease progresses following attempted surgical or radiation interventions. Unfortunately, patients with advanced PCa can develop incurable castration-resistant PCa (CRPCa) due to mutated, variant, or overexpressed AR. Conversely, low or no AR accumulation or activity can also underlie castration resistance. Whether CRPCa is due to aberrant AR activity or AR independence, NF-κB signaling is also implicated in the initiation and maintenance of CRPCa and, thus, the NF-κB pathway may be a promising alternative therapeutic target. In this review, we present evidence that NF-κB signaling promotes CRPCa initiation and progression, describe the dichotomic role of NF-κB in the regulation of AR expression and activity and outline studies that explore NF-κB inhibitors as PCa therapies.

Natural Compounds in Prostate Cancer Prevention and Treatment: Mechanisms of Action and Molecular Targets

Prostate cancer (PCa) represents a major cause of cancer mortality among men in developed countries. Patients with recurrent disease initially respond to androgen-deprivation therapy, but the tumor eventually progresses into castration-resistant PCa; in this condition, tumor cells acquire the ability to escape cell death and develop resistance to current therapies. Thus, new therapeutic approaches for PCa management are urgently needed. In this setting, natural products have been extensively studied for their anti-PCa activities, such as tumor growth suppression, cell death induction, and inhibition of metastasis and angiogenesis. Additionally, numerous studies have shown that phytochemicals can specifically target the androgen receptor (AR) signaling, as well as the PCa stem cells (PCSCs). Interestingly, many clinical trials have been conducted to test the efficacy of nutraceuticals in human subjects, and they have partially confirmed the promising results obtained in vitro and in preclinical models. This article summarizes the anti-cancer mechanisms and therapeutic potentials of different natural compounds in the context of PCa prevention and treatment.

Phytochemicals in Cancer Treatment: From Preclinical Studies to Clinical Practice

Cancer is a severe health problem that continues to be a leading cause of death worldwide. Increasing knowledge of the molecular mechanisms underlying cancer progression has led to the development of a vast number of anticancer drugs. However, the use of chemically synthesized drugs has not significantly improved the overall survival rate over the past few decades. As a result, new strategies and novel chemoprevention agents are needed to complement current cancer therapies to improve efficiency. Naturally occurring compounds from plants known as phytochemicals, serve as vital resources for novel drugs and are also sources for cancer therapy. Some typical examples include taxol analogs, vinca alkaloids such as vincristine, vinblastine, and podophyllotoxin analogs. These phytochemicals often act via regulating molecular pathways which are implicated in growth and progression of cancer. The specific mechanisms include increasing antioxidant status, carcinogen inactivation, inhibiting proliferation, induction of cell cycle arrest and apoptosis; and regulation of the immune system. The primary objective of this review is to describe what we know to date of the active compounds in the natural products, along with their pharmacologic action and molecular or specific targets. Recent trends and gaps in phytochemical based anticancer drug discovery are also explored. The authors wish to expand the phytochemical research area not only for their scientific soundness but also for their potential druggability. Hence, the emphasis is given to information about anticancer phytochemicals which are evaluated at preclinical and clinical level.

Synergistic Action of Stilbenes in Muscadine Grape Berry Extract Shows Better Cytotoxic Potential Against Cancer Cells Than Resveratrol Alone

Muscadine grape is rich in stilbenes, which include resveratrol, piceid, viniferin, pterostilbene, etc. Resveratrol has been extensively studied for its biological activities; however, the synergistic effect of stilbene compounds in berry extracts is poorly understood. The aim of this study was to evaluate the anti-cancer activity of stilbene-rich muscadine berry extract and pure resveratrol. Stilbenes were extracted from ripened berries of muscadine grape cultivars, Pineapple, and Southern Home. HPLC analysis was performed to determine quantity of stilbenes. The extracts were tested for their cytotoxic activity against A549 (lung carcinoma cells), triple negative breast cancer (HCC-1806) and HepG2 (human liver cancer) cells. The stilbene-rich extracts of the muscadine berry extracts showed cytotoxic activity against all of the cells tested. The extracts at 1 μg/mL induced death in 50-80% of cells by 72 h of treatment. About 50 μg/mL of resveratrol was required to induce a similar response in the cells. Further, modulation of genes involved in tumor progression and suppression was significantly (p < 0.0005) higher with the HepG2 cells treated with stilbene-rich berry extracts than the pure resveratrol. This shows that the synergistic activity of stilbenes present in muscadine grape berries have more potent anti-cancer activity than the resveratrol alone.

Precision Nutrition and Cancer Relapse Prevention: A Systematic Literature Review

Cancer mortality rates are undergoing a global downward trend; however, metastasis and relapse after surgery and adjuvant treatments still correlate with poor prognosis and represent the most significant challenges in the treatment of this disease. Advances in genomics, metabolomics, and proteomics are improving our understanding regarding cancer metabolic diversity, resulting in detailed classifications of tumors and raising the effectiveness of precision medicine. Likewise, the growing knowledge of interactions between nutrients and the expression of certain genes could lead to cancer therapies based on precision nutrition strategies. This review aims to identify the recent advances in the knowledge of the mechanistic role of bioactive phytochemicals in foodstuffs in tumor progression, metastasis, and chemo-resistance in order to assess their potential use in precision nutrition therapies targeting relapse in lung, breast, colon, and prostate cancer, and leukemia. A considerable number of bioactive phytochemicals in foodstuffs were identified in the literature with proven effects modulating tumor growth, progression, and metastasis. In addition, the use of foodstuffs in cancer, and specifically in relapse therapies, is being reinforced by the development of different formulations that significantly increase the therapeutic efficiency of these products. This can open the possibility for testing combinations of bioactive phytochemicals with cancer relapse treatments as a potential prevention strategy.

In Vitro Anticancer Properties of Table Grape Powder Extract (GPE) in Prostate Cancer

Although the link between diet and cancer is complex, epidemiological data confirm that diet is a risk factor for prostate cancer and indicate a reduced prostate cancer incidence associated with a diet rich in vegetables and fruits. Because of the known protective effect of grape seed extract (GSE) against prostate cancer, we evaluated the effects of grape powder extract (GPE) on cell viability, proliferation, and metastatic capability. Importantly, we explored the possible novel mechanism of GPE through metastasis-associated protein 1 (MTA1) downregulation in prostate cancer, since our previous studies indicated resveratrol (Res)- and pterostilbene (Pter)-induced MTA1-mediated anticancer activities in prostate cancer. We found that GPE inhibited the cell viability and growth of prostate cancer cells only at high 100 μg/mL concentrations. However, at low 1.5⁻15 μg/mL concentrations, GPE significantly reduced the colony formation and wound healing capabilities of both DU145 and PC3M cells. Moreover, we found that GPE inhibited MTA1 in a dose-dependent manner in these cells, albeit with considerably less potency than Res and Pter. These results indicate that stilbenes such as Res and Pter specifically and potently inhibit MTA1 and MTA1-associated proteins compared to GPE, which contains low concentrations of Res and mainly consists of other flavonoids and anthocyanidins. Our findings support continued interest in GPE as a chemopreventive and anti-cancer agent against prostate cancer but also emphasize the unique and specific properties of stilbenes on MTA1-mediated anticancer effects on prostate cancer.

Phase II Trial of Acai Juice Product in Biochemically Recurrent Prostate Cancer

BACKGROUND

Plant derivatives have been studied as therapies for prostate cancer based on their purported anti-inflammatory and antioxidant properties and low toxicities. The acai berry is an example of a plant rich in phytochemicals, which may slow the growth of prostate cancer.

METHODS

This was a phase II, Simon 2-stage clinical trial in patients with biochemically recurrent prostate cancer with a primary endpoint of prostate-specific antigen (PSA) response. Patients were asymptomatic, with a rising PSA of at least 0.2 ng/mL, and were treated with twice daily intake of Acai Juice Product until PSA progression, with a primary endpoint of PSA response.

RESULTS

Twenty-one patients were enrolled in the first stage of the trial. One of those patients had a PSA response within the study time period. The PSA doubling time was lengthened in 71% of patients (95% confidence interval = 48% to 89%) on the trial, and in a small number of responders, this was sustained over an extended time.

CONCLUSIONS

This study did not meet its primary endpoint of 50% PSA response. Nevertheless, the overall tolerability and effects on PSA stabilization warrant further exploration in a biochemically recurrent population.