Flavonoids and Breast Cancer Risk in Italy

Dietary flavonoid intake and risk of hormone-related cancers: A population-based prospective cohort study

BACKGROUND

Dietary flavonoids may have potential effects on hormone-related cancers (HRCs) due to their anti-cancer properties via regulating hormones and suppressing inflammation and oxidative stress. We aimed to examine the association of flavonoid intake with risks of HRCs and whether this association was mediated by blood biomarkers involved in biological mechanisms.

METHODS

This prospective cohort study from UK Biobank included 187,350 participants free of cancer when the last dietary recall was completed. The dietary intakes of flavonoids and subclasses were assessed using 24-hour dietary recalls. Venous blood was collected at baseline and assayed for biomarkers of inflammation, hormones, and oxidative stress. Hazard ratios (HR) and 95 % confidential intervals (CI) for the associations between flavonoid intake and HRCs risk were estimated by the cause-specific Cox proportional hazards model. The role of blood biomarkers in the flavonoids-HRCs association was investigated through mediation analysis.

RESULTS

Over a median follow-up of 9.5 years, 3,392 female breast cancer, 417 ovarian cancer, 516 endometrial cancer, 4,305 prostate cancer, 45 testicular cancer, and 146 thyroid cancer cases were documented. Compared to the lowest quintile, multivariable-adjusted HRs (95 % CIs) in the highest quintile of total flavonoid intake were 0.89 (0.80-0.99) for breast cancer, 0.68 (0.50-0.92) for ovarian cancer, and 0.88 (0.80-0.98) for female-specific cancers. For subclasses, intakes of flavonols and anthocyanidins were inversely associated with the risk of female-specific cancers (Ptrend <0.05). Anthocyanidin intake was positively related to prostate cancer risk, whereas isoflavone intake was inversely linked to thyroid cancer risk (Ptrend <0.05). Additionally, certain biomarkers of inflammation, hormones and oxidative stress jointly mediated the association of flavonoid intake with the risk of female-specific cancers and prostate cancer.

CONCLUSIONS

Our findings highlighted the importance of dietary flavonoids for the prevention of HRCs in the general population, providing epidemiological evidence for dietary guidelines.

Phloridzin Docosahexaenoate Inhibits Spheroid Formation by Breast Cancer Stem Cells and Exhibits Cytotoxic Effects against Paclitaxel-Resistant Triple Negative Breast Cancer Cells

The eradication of cancer stem cells (CSCs) is vital to successful cancer treatment and overall disease-free survival. CSCs are a sub-population of cells within a tumor that are defined by their capacity for continuous self-renewal and recapitulation of new tumors, demonstrated in vitro through spheroid formation. Flavonoids are a group of phytochemicals with potent anti-oxidant and anti-cancer properties. This paper explores the impact of the flavonoid precursor phloridzin (PZ) linked to the ω-3 fatty acid docosahexaenoate (DHA) on the growth of MCF-7 and paclitaxel-resistant MDA-MB-231-TXL breast cancer cell lines. Spheroid formation assays, acid phosphatase assays, and Western blotting were performed using MCF-7 cells, and the cell viability assays, Annexin-V-488/propidium iodide (PI) staining, and 7-aminoactinomycin D (7-AAD) assays were performed using MDA-MB-231-TXL cells. PZ-DHA significantly reduced spheroid formation, as well as the metabolic activity of MCF-7 breast cancer cells in vitro. Treatment with PZ-DHA also suppressed the metabolic activity of MDA-MB-231-TXL cells and led to apoptosis. PZ-DHA did not have an observable effect on the expression of the drug efflux transporters ATP-binding cassette super-family G member 2 (ABCG2) and multidrug resistance-associated protein 1 (MRP1). PZ-DHA is a potential treatment avenue for chemo-resistant breast cancer and a possible novel CSC therapy. Future pre-clinical studies should explore PZ-DHA as a chemo-preventative agent.

Dietary Inflammatory Index and risk of breast cancer: evidence from a prospective cohort of 67,879 women followed for 20 years in France

BACKGROUND

Inflammation is implicated in breast cancer development, and diet is one of the modifiable risk factors involved in the regulation of chronic inflammation. Previous studies on the association between breast cancer risk and Dietary Inflammatory Indexes (DII) derived from food frequency questionnaires and data on inflammatory potential of dietary components have reported inconsistent results.

OBJECTIVE

To investigate the association between the DII and the risk of breast cancer using data from a large population-based cohort study.

DESIGN

A total of 67,879 women from the E3N cohort were followed from 1993 to 2014. A total of 5686 breast cancer cases were diagnosed during the follow-up. The food frequency questionnaire administered at baseline in 1993 was used to calculate an adapted DII. Cox proportional hazard models using age as the time scale were used to estimate hazard ratios (HR) and 95% confidence intervals (CI). Spline regression was used to determine any dose-response relationship. We also evaluated effect modification by menopausal status, body mass index, smoking status and alcohol consumption.

RESULTS

The median DII score of the study population was slightly pro-inflammatory (DII = + 0.39); ranged from - 4.68 in the lowest quintile to + 4.29 in the highest quintile. The HR increased linearly with the DII (HR per 1SD = 1.04 [95% CI: 1.01, 1.07]), and reached 1.13 [95% CI: 1.04, 1.23] in the 5th quintile group as compared to the first. A positive linear dose-response relationship was also observed when modeling DII with spline functions. Slightly higher HRs were observed in non-smokers (HR _{for 1-SD increase} 1.06 [95% CI: 1.02, 1.10]; p trend = 0.001) and in low-alcohol consumers (≤ 1 glass/day) (HR _{for 1-SD increase} 1.05 [95% CI: 1.01, 1.08]; p trend = 0.002).

CONCLUSION

Our results suggest a positive association between DII and breast cancer risk. Consequently, the promotion of anti-inflammatory diet may contribute to breast cancer prevention.

Evidence of Flavonoids on Disease Prevention

A growing body of evidence highlights the properties of flavonoids in natural foods for disease prevention. Due to their antioxidative, anti-inflammatory, and anti-carcinogenic activities, flavonoids have been revealed to benefit skeletal muscle, liver, pancreas, adipocytes, and neural cells. In this review, we introduced the basic classification, natural sources, and biochemical properties of flavonoids, then summarize the experimental results and underlying molecular mechanisms concerning the effects of flavonoid consumption on obesity, cancers, and neurogenerative diseases that greatly threaten public health. Especially, the dosage and duration of flavonoids intervening in these diseases are discussed, which might guide healthy dietary habits for people of different physical status.

Anti-Inflammatory Mechanisms of Dietary Flavones: Tapping into Nature to Control Chronic Inflammation in Obesity and Cancer

Flavones are natural phytochemicals broadly distributed in our diet. Their anti-inflammatory properties provide unique opportunities to control the innate immune system and inflammation. Here, we review the role of flavones in chronic inflammation with an emphasis on their impact on the molecular mechanisms underlying inflammatory diseases including obesity and cancer. Flavones can influence the innate immune cell repertoire restoring the immune landscape. Flavones impinge on NF-κB, STAT, COX-2, or NLRP3 inflammasome pathways reestablishing immune homeostasis. Devoid of adverse side effects, flavones could present alternative opportunities for the treatment and prevention of chronic inflammation that contributes to obesity and cancer.

Chemopreventive and therapeutic properties of anthocyanins in breast cancer: A comprehensive review

Anthocyanins have received the attention of the scientific community because of their antioxidant, antimetastatic, and cancer-inhibitory properties. The aim of this review is to comprehensively summarize the possible mechanisms by which anthocyanins exhibit anticarcinogenic properties in breast cancer (BC) cell lines and animal models. Anthocyanins inhibit proinflammatory, signal transducer and activator of transcription 3, and nuclear factor kappa-light-chain-enhancer of activated B cell pathways and increase the activities of detoxification enzymes. In addition, downregulation of metalloproteinases by anthocyanins inhibits tumor invasion and metastatic processes in experimental systems. Anthocyanins mediate anticancer and angiogenic effects by modifying multiple receptor families. Furthermore, inhibition of cell-cycle upstream polo-like kinase signaling, the chromosomal replication checkpoint, and ataxia telangiectasia mutated signaling may contribute to the anticarcinogenic effects of anthocyanins. Finally, anthocyanins induce mitochondrial-mediated apoptosis and downregulate the phosphatidylinositol-3-kinase/AKT/mTOR pathway. In conclusion, anthocyanins have been shown to exert potential antitumor effects against breast carcinogenesis in vitro and in vivo, providing insights into the use of anthocyanins as a natural chemopreventive intervention in BC.

Apigenin Targets MicroRNA-155, Enhances SHIP-1 Expression, and Augments Anti-Tumor Responses in Pancreatic Cancer

Pancreatic cancer (PC) is a deadly disease with a grim prognosis. Pancreatic tumor derived factors (TDF) contribute to the induction of an immunosuppressive tumor microenvironment (TME) that impedes the effectiveness of immunotherapy. PC-induced microRNA-155 (miRNA-155) represses expression of Src homology 2 (SH2) domain-containing Inositol 5'-phosphatase-1 (SHIP-1), a regulator of myeloid cell development and function, thus impacting anti-tumor immunity. We recently reported that the bioflavonoid apigenin (API) increased SHIP-1 expression which correlated with the expansion of tumoricidal macrophages (TAM) and improved anti-tumor immune responses in the TME of mice with PC. We now show that API transcriptionally regulates SHIP-1 expression via the suppression of miRNA-155, impacting anti-tumor immune responses in the bone marrow (BM) and TME of mice with PC. We discovered that API reduced miRNA-155 in the PC milieu, which induced SHIP-1 expression. This promoted the restoration of myelopoiesis and increased anti-tumor immune responses in the TME of heterotopic, orthotopic and transgenic SHIP-1 knockout preclinical mouse models of PC. Our results suggest that manipulating SHIP-1 through miR-155 may assist in augmenting anti-tumor immune responses and aid in the therapeutic intervention of PC.

Consumption of flavonoids and risk of hormone-related cancers: a systematic review and meta-analysis of observational studies

BACKGROUND

Flavonoids seem to have hormone-like and anti-hormone properties so that the consumption of flavonoids may have potential effects on hormone-related cancers (HRCs), but the findings have been inconsistent so far. This meta-analysis was aimed to explore the association between flavonoids intake and HRCs risk among observational studies.

METHODS

Qualified articles, published on PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI) from January 1999 to March 2022 and focused on relationships between flavonoids (total, subclass of and individual flavonoids) and HRCs (breast, ovarian, endometrial, thyroid, prostate and testicular cancer), were retrieved for pooled analysis. Random effects models were performed to calculate the pooled odds ratios (ORs) and corresponding 95% confidence intervals (CIs). Funnel plots and Begg's/Egger's test were used to evaluate the publication bias. Subgroup analyses and sensitivity analyses were conducted to explore the origins of heterogeneity.

RESULTS

All included studies were rated as medium or high quality. Higher consumption of flavonols (OR = 0.85, 95% CI: 0.76-0.94), flavones (OR = 0.85, 95% CI: 0.77-0.95) and isoflavones (OR = 0.87, 95% CI: 0.82-0.92) was associated with a decreased risk of women-specific cancers (breast, ovarian and endometrial cancer), while the higher intake of total flavonoids was linked to a significantly elevated risk of prostate cancer (OR = 1.11, 95% CI: 1.02-1.21). A little evidence implied that thyroid cancer risk was augmented with the higher intake of flavones (OR = 1.24, 95% CI: 1.03-1.50) and flavanones (OR = 1.31, 95% CI: 1.09-1.57).

CONCLUSIONS

The present study suggests evidence that intake of total flavonoids, flavonols, flavones, flavanones, flavan-3-ols and isoflavones would be associated with a lower or higher risk of HRCs, which perhaps provides guidance for diet guidelines to a certain extent.

TRIAL REGISTRATION

This protocol has been registered on PROSPERO with registration number CRD42020200720 .

Impacts of nutritive and bioactive compounds on cancer development and therapy

For persons who survive with progressive cancer, nutritional therapy and exercise may be significant factors to improve the health condition and life quality of cancer patients. Nutritional therapy and medications are essential to managing progressive cancer. Cancer survivors, as well as cancer patients, are mostly extremely encouraged to search for knowledge about the selection of diet, exercise, and dietary supplements to recover as well as maintain their treatment consequences, living quality, and survival of patients. A healthy diet plays an important role in cancer treatment. Different articles are studied to collect information and knowledge about the use of nutrients in cancer treatment as well as cancer prevention. The report deliberates nutrition and exercise strategies during the range of cancer care, emphasizing significant concerns during treatment of cancer and for patients of advanced cancer, but concentrating mostly on the requirements of the population of persons who are healthy or who have constant disease following their repossession from management. It also deliberates choice nutrition and exercise problems such as dietary supplements, food care, food selections, and weight; problems interrelated to designated cancer sites, and common questions about diet, and cancer survival. Decrease the side effects of medicines both during and after treatment.

Dietary Intake of Polyphenols and the Risk of Breast Cancer: a Case-Control Study

Despite mounting evidence that dietary polyphenols might have a protective role against the risk of breast cancer (BC), few studies have assessed the relationship between intake of polyphenol classes and subclasses with BC. Thus, we examined the relationship between dietary polyphenol classes and individual polyphenol subclasses and the risk of BC. Overall, 134 newly diagnosed BC patients and 267 healthy hospitalized controls were studied. Dietary intake was assessed using a validated 168-item food frequency questionnaire (FFQ). To estimate dietary intake of polyphenols, polyphenol content (flavonoids, lignans, stilbenes and phenolic acids) of 80 food items were derived from an updated version of the phenol explorer database containing information on the effects of food processing on polyphenol content. The dietary polyphenol intake was calculated by matching the subjects' food consumption data with our polyphenol content database. Multivariate logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Controls had higher intake of total polyphenol (marginally significant; p = 0.07), hydroxycinnamic acid (marginally significant; p = 0.05) and lignan (p = 0.01). After adjusting for potential confounders, high consumption of lignans (highest vs. lowest tertile: OR, 0.51; 95% CI, 0.26–0.97; p for trend = 0.04) associated with decreased risk of BC. There was no significant relationship between intake of other polyphenols and risk of BC. Our findings suggest that high lignan intake is associated with a reduced risk of BC.

Association between Dietary Intake of Flavonoids and Cancer Recurrence among Breast Cancer Survivors

Intake of flavonoids is associated with the incidence of breast cancer, but the association between the intake of flavonoids and cancer recurrence is unclear. This study aimed to investigate the hypothesis that intake of flavonoids and flavonoid-rich foods is negatively associated with cancer recurrence. Among 572 women who underwent breast cancer surgery, 66 patients had a cancer recurrence. Dietary data were collected using a structured 24-h dietary recall, and intake of flavonoids was calculated based on the Korea Rural Development Administration flavonoid database. Among overweight and obese patients, disease-free survival was associated with intake of flavonoids (p = 0.004) and flavonoid-rich foods (p = 0.003). Intake of flavonoids (hazard ratio (HR) = 0.249, 95% confidence interval (CI): 0.09–0.64) and flavonoid-rich foods (HR = 0.244, 95% CI: 0.09–0.66) was negatively associated with cancer recurrence after adjusting for confounding factors in overweight and obese patients. Consumption of flavonoids and flavonoid-rich foods was lower in overweight and obese patients with cancer recurrence than those without recurrence and in normal-weight patients. This study suggests that intake of flavonoids and flavonoid-rich foods could have beneficial effects on cancer recurrence in overweight and obese breast cancer survivors.

Polyphenols Modulating Effects of PD-L1/PD-1 Checkpoint and EMT-Mediated PD-L1 Overexpression in Breast Cancer

Investigating dietary polyphenolic compounds as antitumor agents are rising due to the growing evidence of the close association between immunity and cancer. Cancer cells elude immune surveillance for enhancing their progression and metastasis utilizing various mechanisms. These mechanisms include the upregulation of programmed death-ligand 1 (PD-L1) expression and Epithelial-to-Mesenchymal Transition (EMT) cell phenotype activation. In addition to its role in stimulating normal embryonic development, EMT has been identified as a critical driver in various aspects of cancer pathology, including carcinogenesis, metastasis, and drug resistance. Furthermore, EMT conversion to another phenotype, Mesenchymal-to-Epithelial Transition (MET), is crucial in developing cancer metastasis. A central mechanism in the upregulation of PD-L1 expression in various cancer types is EMT signaling activation. In breast cancer (BC) cells, the upregulated level of PD-L1 has become a critical target in cancer therapy. Various signal transduction pathways are involved in EMT-mediated PD-L1 checkpoint overexpression. Three main groups are considered potential targets in EMT development; the effectors (E-cadherin and Vimentin), the regulators (Zeb, Twist, and Snail), and the inducers that include members of the transforming growth factor-beta (TGF-β). Meanwhile, the correlation between consuming flavonoid-rich food and the lower risk of cancers has been demonstrated. In BC, polyphenols were found to downregulate PD-L1 expression. This review highlights the effects of polyphenols on the EMT process by inhibiting mesenchymal proteins and upregulating the epithelial phenotype. This multifunctional mechanism could hold promises in the prevention and treating breast cancer.

Apigenin ameliorates doxorubicin-induced renal injury via inhibition of oxidative stress and inflammation

BACKGROUND AND OBJECTIVE

Doxorubicin (DOX) is an anthracycline antitumor antibiotic widely utilized in treating various tumors. Nevertheless, the toxicity of DOX toward normal cells limits its applicability, with nephrotoxicity considered a major dose-limiting adverse effect. Apigenin (APG), a flavonoid widely distributed in natural plants, has been reported to have antioxidant, anti-inflammatory, and mild tumor-suppressive properties. In this study, we investigated the role of APG in DOX-induced nephrotoxicity and chemotherapeutic efficacy.

METHODS

Male BALB/c mice were administered DOX (11.5 mg/kg) via the tail vein to establish the DOX nephropathy model. After treatment with or without APG (125, 250, and 500 mg/kg) for two weeks, urine, serum, and tissue samples were collected to evaluate proteinuria, serum albumin, serum creatinine (Scr), blood urea nitrogen (BUN), superoxide dismutase (SOD) activity, malondialdehyde (MDA), glutathione (GSH), and pathological changes. Rat renal tubular epithelial cells (NRK52E), murine podocyte cells (MPC5), and murine breast cancer cells (4T1) were utilized to verify the effect of APG on DOX-induced cell injury. An MTT assay was employed to analyze cell viability. Apoptosis was evaluated using a colorimetric TUNEL staining and cleaved caspase-3 protein analysis by western blotting. A reactive oxygen species (ROS)/superoxide (O2-) fluorescence probe was employed to determine oxidative injury. Western blotting was used to analyze nephrin, α-smooth muscle actin (α-SMA), collagen I (Col1), fibronectin (FN), and SOD2 expression. The mRNA levels of tumor necrosis factor-α (TNF-α), interleukin-18 (IL-18), IL-6, NACHT, LRR, PYD domain-containing protein 3 (NLRP3), caspase-1, and IL-1β were tested by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

APG ameliorated DOX-elicited renal injuries in both the glomeruli and tubules. The DOX + APG groups had much lower tissue MDA, IL-6, TNF-α, NLRP3, caspase-1, and IL-1β levels and generation of intracellular ROS, but significantly higher SOD activity and GSH levels compared to those of the DOX group. Additionally, APG attenuated DOX-induced morphological changes, loss of cellular viability, and apoptosis in NRK-52E and MPC-5 cells, but not in 4T1 cells.

CONCLUSION

APG has a protective role against DOX-induced nephrotoxicity, without weakening DOX cytotoxicity in malignant tumors. Thus, APG may serve as a potential protective agent against renal injury and inflammatory diseases and may be a promising candidate to attenuate renal toxicity in cancer patients treated with DOX.

Endocrine disrupting chemicals and breast cancer: a systematic review of epidemiological studies

BACKGROUND

Endocrine-disrupting compounds (EDCs) are ubiquitous substances that are found in our everyday lives, including pesticides, plasticizers, pharmaceutical agents, personal care products, and also in food products and food packaging. Increasing epidemiological evidence suggest that EDCs may affect the development or progression of breast cancer and consequently lead to lifelong harmful health consequences, especially when exposure occurs during early life in humans. Yet so far no appraisal of the available evidence has been conducted on this topic.

OBJECTIVE

To systematically review all the available epidemiological studies about the association of the levels of environmental exposures of EDCs with breast cancer risk.

METHODS

The search was performed in accordance with the PRISMA guidelines. We retrieved articles from PubMed (MEDLINE) until 10 March 2021. The key words used in this research were: "Endocrine disruptor(s)" OR "Endocrine disrupting chemical(s)" OR any of the EDCs mentioned below AND "Breast cancer" to locate all relevant articles published. We included only cohort studies and case-control studies. All relevant articles were accessed in full text and were evaluated and summarized in tables.

RESULTS

We identified 131 studies that met the search criteria and were included in this systematic review. EDCs reviewed herein included pesticides (e.g. p,p'-dichlorodiphenyltrichloroethane (DDT), p,p'-dichlorodiphenyldichloroethylene (DDE), atrazine, 2,3,7,8-tetrachloridibenzo-p-dioxin (TCDD or dioxin)), synthetic chemicals (e.g. bisphenol A (BPA), phthalates, per- and polyfluoroalkyl substances (PFAS), parabens, polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), contraceptive pills), phytoestrogens (e.g. genistein, resveratrol), and certain mycotoxins (e.g. zearalenone). Most studies assessed environmental EDCs exposure via biomarker measurements.

CONCLUSION

We identified certain EDC exposures could potentially elevate the risk of breast cancer. As majority of EDCs are highly persistent in the environment and bio-accumulative, it is essential to assess the long-term impacts of EDC exposures, especially multi-generational and transgenerational. Also, since food is often a major route of exposure to EDCs, well-designed exposure assessments of potential EDCs in food and food packing are necessary and their potential link to breast cancer development need to be carefully evaluated for subsequent EDC policy making and regulations.

Assessing the Impact of Phytochemicals on Immune Checkpoints: Implications for Cancer Immunotherapy

Phytochemicals are the basis for many anticancer drugs currently in clinical use, as well as a potential source of future cancer treatments. Some phytochemicals have been found to modify the expression of checkpoint inhibitors of the immune response, as well as kill cancer cells. Cancer cells, in turn, may evade detection by the immune system by expressing molecules such as programmed death ligand 1 (PD-L1) that interacts with programmed cell death 1 (PD-1) on T cells to inhibit T cell activation and effector function. Phytochemicals have direct effects on cancer cells and/or T cells that may impact PD-L1/PD1 interactions, although this may vary depending on the phytochemical in question. Flow cytometric analysis of cancer cells stained with anti-PD-L1 antibodies following treatment with a given phytochemical enables the detection of any alteration in PD-L1 expression. The effect of the phytochemical on T cell function can be assessed using proliferation assays (e.g., tritiated thymidine incorporation, flow cytometric analysis of Oregon Green 488-stained cells) and enzyme-linked immunosorbent assay of interleukin-2 content in culture supernatants. Additional study is needed to better understand the impact of phytochemicals on cancer immunotherapy.

Apigenin, a Partial Antagonist of the Estrogen Receptor (ER), Inhibits ER-Positive Breast Cancer Cell Proliferation through Akt/FOXM1 Signaling

Approximately 80% of breast cancer (BC) cases express the estrogen receptor (ER), and 30-40% of these cases acquire resistance to endocrine therapies over time. Hyperactivation of Akt is one of the mechanisms by which endocrine resistance is acquired. Apigenin (Api), a flavone found in several plant foods, has shown beneficial effects in cancer and chronic diseases. Here, we studied the therapeutic potential of Api in the treatment of ER-positive, endocrine therapy-resistant BC. To achieve this objective, we stably overexpressed the constitutively active form of the Akt protein in MCF-7 cells (named the MCF-7/Akt clone). The proliferation of MCF-7/Akt cells is partially independent of estradiol (E2) and exhibits an incomplete response to the anti-estrogen agent 4-hydroxytamoxifen, demonstrating the resistance of these cells to hormone therapy. Api exerts an antiproliferative effect on the MCF-7/Akt clone. Api inhibits the proliferative effect of E2 by inducing G2/M phase cell cycle arrest and apoptosis. Importantly, Api inhibits the Akt/FOXM1 signaling pathway by decreasing the expression of FOXM1, a key transcription factor involved in the cell cycle. Api also alters the expression of genes regulated by FOXM1, including cell cycle-related genes, particularly in the MCF-7/Akt clone. Together, our results strengthen the therapeutic potential of Api for the treatment of endocrine-resistant BC.

Plant Natural Compounds in the Treatment of Adrenocortical Tumors

Plant natural products are a plethora of diverse and complex molecules produced by the plant secondary metabolism. Among these, many can reserve beneficial or curative properties when employed to treat human diseases. Even in cancer, they can be successfully used and indeed numerous phytochemicals exert antineoplastic activity. The most common molecules derived from plants and used in the fight against cancer are polyphenols, i.e., quercetin, genistein, resveratrol, curcumin, etc. Despite valuable data especially in preclinical models on such compounds, few of them are currently used in the medical practice. Also, in adrenocortical tumors (ACT), phytochemicals are scarcely or not at all used. This work summarizes the available research on phytochemicals used against ACT and adrenocortical cancer, a very rare disease with poor prognosis and high metastatic potential, and wants to contribute to stimulate preclinical and clinical research to find new therapeutic strategies among the overabundance of biomolecules produced by the plant kingdom.

Pretreatment Dietary Patterns, Serum Carotenoids and Tocopherols Influence Tumor Immune Response in Head and Neck Squamous Cell Carcinoma

BACKGROUND

Tumor infiltrating lymphocytes (TILs) aid in informing treatment for head and neck squamous cell carcinoma (HNSCC). Nevertheless, little is known about the role of diet on TILs.

METHODS

Immunohistologic expression of CD4, CD8, CD68, CD103, CD104 and FOXP3 were assessed in tissue microarrays from 233 previously untreated HNSCC patients. Associations between these markers and pretreatment dietary patterns were evaluated using linear regression. Associations between baseline serum carotenoids, tocopherols and TILs were assessed using logistic regression. Cox models evaluated the association between diet and TILs on overall and recurrence-free survival.

RESULTS

Consumption of a Western dietary pattern was associated with lower CD8+ and FOXP3+ infiltrates (p-value:0.03 and 0.02, respectively). Multivariable logistic regression models demonstrated significantly higher CD8+ (OR:2.21;p-value:0.001) and FOXP3+ (OR:4.26;p-value:<0.0001) among patients with high gamma tocopherol. Conversely, high levels of xanthophylls (OR:0.12;p-value:<0.0001), lycopene (OR:0.36;p-value:0.0001) and total carotenoids(OR:0.31;p-value: <0.0001) were associated with significantly lower CD68+. Among those with high CD4+ (HR:1.77;p-value:0.03), CD68+ (HR:2.42;p-value:0.004), CD103+ (HR:3.64;p-value:0.03) and FOXP3+ (HR:3.09;p-value:0.05), having a high Western dietary pattern increased the risk of overall mortality when compared to a low Western dietary pattern.

CONCLUSION

Dietary patterns and serum carotenoids may play an important role in modifying TILs, and ultimately, outcome after diagnosis with HNSCC.

Associations between serum concentration of flavonoids and breast cancer risk among Chinese women

PURPOSE

In vitro and in vivo studies suggested that flavonols, flavones, flavanones and flavan-3-ols have preventive effects on breast carcinogenesis. Epidemiological evidence about the associations between these flavonoid biomarkers and breast cancer risk is limited. This study aimed to investigate the association between serum concentration of these flavonoids and breast cancer risk among Chinese women.

METHODS

This hospital-based case-control study recruited 792 breast cancer cases and 813 age frequency-matched (5-year interval) controls who provided eligible blood samples in Guangdong Province, China. Ultra-high-performance liquid chromatography-tandem mass spectrometry was used to measure flavonoids. Unconditional logistic regression was used to estimate the odds ratio (OR) and 95% confidence internal (CI).

RESULTS

Higher concentrations of serum flavonols, isorhamnetin, kaempferol, flavanones and naringenin were significantly associated with lower breast cancer risk, with adjusted ORs (95% CIs) for the highest versus the lowest group of 0.66 (0.49-0.89) for flavonols, 0.52 (0.38-0.70) for isorhamnetin, 0.60 (0.45-0.80) for kaempferol, 0.65 (0.49-0.87) for flavanones and 0.45 (0.34-0.60) for naringenin, respectively. Significant positive associations were observed between serum flavan-3-ols, epigallocatechin, epigallocatechin-3-gallate and breast cancer risk. No significant associations were observed for serum quercetin, flavones, apigenin, luteolin, hesperetin, catechin, epicatechin and epicatechin-3-gallate with overall breast cancer risk.

CONCLUSIONS

This study suggested that serum flavonols and flavanones were inversely associated with breast cancer risk and serum flavan-3-ols were positively associated with breast cancer risk. Serum flavones were not associated with overall breast cancer risk. These findings warrant further confirmation in prospective studies.

Association between Polyphenol Intake and Breast Cancer Risk by Menopausal and Hormone Receptor Status

There is limited evidence of phenolic compounds acting as protective agents on several cancer types, including breast cancer (BC). Nevertheless, some polyphenol classes have not been investigated and there is a lack of studies assessing the effect on menopausal status and hormone receptor status as influenced by these compounds. The objective of this study is to evaluate the association between the intake of all polyphenol classes in relation to the BC risk by menopausal and hormone receptor status. We used data from a population-based multi-case-control study (MCC-Spain) including 1472 BC cases and 1577 controls from 12 different regions of Spain. The odds ratios (ORs) with 95% CI were calculated using logistic regression of mixed effects by quartiles and log2 of polyphenol intakes (adjusted for the residual method) of overall BC, menopausal and receptor status. No associations were found between total intake of polyphenols and BC risk. However, inverse associations were found between stilbenes and all BC risk (OR_{Q4 vs. Q1}: 0.70, 95%CI: 0.56–0.89, P_trend = 0.001), the consumption of hydroxybenzaldehydes (OR_{Q4 vs. Q1}: 0.75, 95%CI: 0.59–0.93, P_trend = 0.012) and hydroxycoumarins (OR_{Q4 vs. Q1}: 0.73, 95%CI: 0.57–0.93; P_trend = 0.005) were also inversely associated. The intake of stilbenes, hydroxybenzaldehydes and hydroxycoumarins can contribute to BC reduction risk on all menopausal and receptor statuses.

Flavonoids and Other Polyphenols Act as Epigenetic Modifiers in Breast Cancer

Breast cancer is a common cancer that occurs due to different epigenetic alterations and genetic mutations. Various epidemiological studies have demonstrated an inverse correlation between breast cancer incidence and flavonoid intake. The anti-cancer action of flavonoids, a class of polyphenolic compounds that are present in plants, as secondary metabolites has been a major topic of research for many years. Our review analysis demonstrates that flavonoids exhibit anti-cancer activity against breast cancer occurring in different ethnic populations. Breast cancer subtype and menopausal status are the key factors in inducing the flavonoid's anti-cancer action in breast cancer. The dose is another key factor, with research showing that approximately 10 mg/day of isoflavones is required to inhibit breast cancer occurrence. In addition, flavonoids also influence the epigenetic machinery in breast cancer, with research demonstrating that epigallocatechin, genistein, and resveratrol all inhibited DNA methyltransferase and altered chromatin modification in breast cancer. These flavonoids can induce the expression of different tumor suppressor genes that may contribute to decreasing breast cancer progression and metastasis. Additional studies are required to confirm the contribution of epigenetic modifications by flavonoids to breast cancer prevention.

Chemoprevention of Breast Cancer With Vitamins and Micronutrients: A Concise Review

Numerous dietary components and vitamins have been found to inhibit the molecular events and signalling pathways associated with various stages of breast cancer development. To identify the vitamins and dietary micronutrients that exert protective effects against breast cancer and define their mechanism of action, we performed a literature review of in vitro, animal and epidemiological studies and selected the in vitro and animal studies with robust molecular evidence and the epidemiological studies reporting statistically significant inverse associations for a breast cancer-specific protective effect. There is sufficient evidence from in vitro, animal and epidemiological human studies that certain vitamins, such as vitamin D3, folate, vitamin B6, and beta carotene as well as dietary micronutrients, such as curcumin, piperine, sulforaphane, indole-3-carbinol, quercetin, epigallocatechin gallate (EGCG) and omega-3 polyunsaturated fatty acids (PUFAs), display an antitumoral activity against breast cancer and have the potential to offer a natural strategy for breast cancer chemoprevention and reduce the risk of breast cancer recurrence. Therefore, a supplement that contains these micronutrients, using the safest form and dosage should be investigated in future breast cancer chemoprevention studies and as part of standard breast cancer therapy.

A Review on Flavonoid Apigenin: Dietary Intake, ADME, Antimicrobial Effects, and Interactions with Human Gut Microbiota

Apigenin is a flavonoid of low toxicity and multiple beneficial bioactivities. Published reviews all focused on the findings using eukaryotic cells, animal models, or epidemiological studies covering the pharmacokinetics, cancer chemoprevention, and drug interactions of apigenin; however, no review is available on the antimicrobial effects of apigenin. Research proves that dietary apigenin passes through the upper gastrointestinal tract and reaches the colon after consumption. For that reason, it is worthwhile to study the potential interactions between apigenin and human gut microbiota. This review summarizes studies on antimicrobial effects of apigenin as well as what has been reported on apigenin and human gut microbiota. Various levels of effectiveness have been reported on apigenin's antibacterial, antifungal, and antiparasitic capability. It has been shown that apigenin or its glycosides are degraded into smaller metabolites by certain gut bacteria which can regulate the human body after absorption. How apigenin contributes to the structural and functional changes in human gut microbiota as well as the bioactivities of apigenin bacterial metabolites are worth further investigation.

Dietary Flavonoids for Immunoregulation and Cancer: Food Design for Targeting Disease

Flavonoids, one of the most abundant phytochemicals in a diet rich in fruits and vegetables, have been recognized as possessing anti-proliferative, antioxidant, anti-inflammatory, and estrogenic activities. Numerous cellular and animal-based studies show that flavonoids can function as antioxidants by preventing DNA damage and scavenging reactive oxygen radicals, inhibiting formation of DNA adducts, enhancing DNA repair, interfering with chemical damage by induction of Phase II enzymes, and modifying signaling pathways. Recent evidence also shows their ability to regulate the immune system. However, findings from clinical trials have been mixed with no clear consensus on dose, frequency, or type of flavonoids best suited to elicit many of the beneficial effects. Delivery of these bioactive compounds to their biological targets through "targeted designed" food processing strategies is critical to reach effective concentration in vivo. Thus, the identification of novel approaches that optimize flavonoid bioavailability is essential for their successful clinical application. In this review, we discuss the relevance of increasing flavonoid bioavailability, by agricultural engineering and "targeted food design" in the context of the immune system and cancer.

Flavonoids: New Frontier for Immuno-Regulation and Breast Cancer Control

Breast cancer (BC) remains the second most common cause of cancer-related deaths in women in the US, despite advances in detection and treatment. In addition, breast cancer survivors often struggle with long-term treatment related comorbidities. Identifying novel therapies that are effective while minimizing toxicity is critical in curtailing this disease. Flavonoids, a subclass of plant polyphenols, are emerging as promising treatment options for the prevention and treatment of breast cancer. Recent evidence suggests that in addition to anti-oxidant properties, flavonoids can directly interact with proteins, making them ideal small molecules for the modulation of enzymes, transcription factors and cell surface receptors. Of particular interest is the ability of flavonoids to modulate the tumor associated macrophage function. However, clinical applications of flavonoids in cancer trials are limited. Epidemiological and smaller clinical studies have been largely hypothesis generating. Future research should aim at addressing known challenges with a broader use of preclinical models and investigating enhanced dose-delivery systems that can overcome limited bioavailability of dietary flavonoids. In this review, we discuss the structure-functional impact of flavonoids and their action on breast tumor cells and the tumor microenvironment, with an emphasis on their clinical role in the prevention and treatment of breast cancer.

Nutritional Relevance of Flavonoids in Disease Prevention

Flavonoids are not essential nutrients in that their absence from the diet does not produce deficiency conditions in animals and man. However, many have important similarities to pharmacological agents used in the treatment of disease. Their role as dietary components in disease prevention is less clear. Many potentially anti-carcinogenic and anti-atherogenic effects observed in cell cultures will not be of nutritional relevance unless flavonoids gain access to appropriate cellular sites. The bioavailability of flavonoids will depend on numerous factors including molecular structure, the amount consumed, the food matrix, degree of bioconversion in the gut and tissues, the nutrient status of the host and genetic factors. Moreover, extensive and rapid intestinal and hepatic metabolism of flavonoids suggests that the body may treat them as xenobiotic and potentially toxic compounds requiring rapid elimination. Consequently, in addition to potential health benefits, possible adverse effects of flavonoids in the diet also need to be considered when assessing their roles in the prevention of degenerative diseases.

The Therapeutic Potential of Apigenin

Several plant bioactive compounds have exhibited functional activities that suggest they could play a remarkable role in preventing a wide range of chronic diseases. The largest group of naturally-occurring polyphenols are the flavonoids, including apigenin. The present work is an updated overview of apigenin, focusing on its health-promoting effects/therapeutic functions and, in particular, results of in vivo research. In addition to an introduction to its chemistry, nutraceutical features have also been described. The main key findings from in vivo research, including animal models and human studies, are summarized. The beneficial indications are reported and discussed in detail, including effects in diabetes, amnesia and Alzheimer's disease, depression and insomnia, cancer, etc. Finally, data on flavonoids from the main public databases are gathered to highlight the apigenin's key role in dietary assessment and in the evaluation of a formulated diet, to determine exposure and to investigate its health effects in vivo.

Bioactivities of Phenolics by Focusing on Suppression of Chronic Diseases: A Review

Phenolics, which are secondary metabolites of plants, exhibit remarkable bioactivities. In this contribution, we have focused on their protective effect against chronic diseases rather than their antioxidant activities, which have been widely discussed in the literature. A large body of epidemiological studies has proven the bioactivities of phenolics in both standard compounds and natural extracts: namely, anticancer, anti-inflammatory, and antibacterial activities as well as reducing diabetes, cardiovascular disease, and neurodegenerative disease. Phenolics also display anti-analgesic, anti-allergic, and anti-Alzheimer’s properties. Thus, this review provides crucial information for better understanding the bioactivities of phenolics in foods and fills a gap in the existing collective and overall knowledge in the field.

The Flavonoid Apigenin Is a Progesterone Receptor Modulator with In Vivo Activity in the Uterus

Apigenin is a flavonoid with well-documented anti-cancer properties; however, its mechanisms of action are still unclear. We previously identified apigenin as a potential phytoprogestin, a natural product with a chemical scaffold that interacts with the progesterone receptor (PR). Our objective was to characterize the ability of apigenin to interact with PR through molecular docking studies, in vitro activity assays, and the ability of apigenin to elicit progestin-like effects in vivo. Molecular docking confirmed that apigenin could interact with PR, though with lower affinity than progesterone due to fewer van der Waals interactions. In Ishikawa cells stably expressing PR-B, apigenin significantly increased progesterone response element/luciferase (PRE/Luc) activity at 5 and 10 μM, but not in the parental Ishikawa cells that lack PR expression. In the presence of 100 nM of progesterone, 10 μM apigenin reduced PRE/Luc activity, indicative of mixed agonist activity. Apigenin also triggered degradation of PR in Ishikawa PR-B cells as measured by western blot. Apigenin reduced proliferation of Ishikawa cells, but through a PR-independent mechanism. In contrast, apigenin and progesterone both stimulated proliferation of T47D cells, an effect blocked by RU486. Apigenin activated other nuclear receptors evidenced by increased luciferase activity in MDA-MB-231 cells, which are PR negative. In vivo, apigenin blocked the genistein-stimulated increase in uterine epithelial cell height; stimulated endometrial expression of Hand2, a transcription factor stimulated by PR, and significantly reduced genistein-induced proliferation. In summary, apigenin is a phytoprogestin, with mixed agonist activity that demonstrates activity in vivo by hindering estrogen receptor-mediated uterine proliferation.

Flavan-3-ols consumption and cancer risk: A meta-analysis of epidemiologic studies

Although numerous in vitro studies and animal model data have suggested that flavan-3-ols, the most common subclass of flavonoids in the diet, may exert protective effects against cancer, epidemiologic studies have reported inconclusive results for the association between flavan-3-ols intake and cancer risk. Therefore, we conducted this meta-analysis of epidemiologic studies to investigate the preventive effects of flavan-3-ols on various types of cancers. A total of 43 epidemiologic studies, consisting of 25 case-control and 18 prospective cohort studies, were included. A significant inverse association was shown between flavan-3-ols intake and the risk of overall cancer (relative risk (RR) 0.935, 95%CI: 0.891-0.981). When cancer types were separately analyzed, a statistically significant protective effect of flavan-3-ols consumption was observed in rectal cancer (RR 0.838, 95%CI: 0.733-0.958), oropharyngeal and laryngeal cancer (RR 0.759, 95%CI: 0.581-0.993), breast (RR 0.885, 95%CI: 0.790-0.991) in case-control studies and stomach cancer in women (RR 0.633, 95%CI: 0.468-0.858). Our analysis indicates the potential benefits of flavan-3-ols in cancer prevention.

Fresh-Cut Onion: A Review on Processing, Health Benefits, and Shelf-Life

The ready-to-eat produce market has grown rapidly because of the health benefits and convenience associated with these products. Onion is widely used as an ingredient in an extensive range of recipes from breakfast to dinner and in nearly every ethnic cuisine. However, cutting/chopping of onion is a nuisance to many consumers due to the lachrymatory properties of the volatiles generated that bring tears to eyes and leave a distinct odor on hands. As a result, there is now an increasing demand for fresh-cut, value-added, and ready-to-eat onion in households, as well as large-scale uses in retail, food service, and various food industries, mainly due to the end-use convenience. Despite these benefits, fresh-cut onion products present considerable challenges due to tissue damage, resulting in chemical and physiological reactions that limit product shelf-life. Intensive discoloration, microbial growth, softening, and off-odor are the typical deteriorations that need to be controlled through the application of suitable preservation methods. This article reviews the literature related to the fresh-cut onion, focusing on its constituents, nutritional and health benefits, production methods, quality changes throughout storage, and technologies available to increase product shelf-life.

Plant flavone apigenin: An emerging anticancer agent

Research in cancer chemoprevention provides convincing evidence that increased intake of vegetables and fruits may reduce the risk of several human malignancies. Phytochemicals present therein provide beneficial anti-inflammatory and antioxidant properties that serve to improve the cellular microenvironment. Compounds known as flavonoids categorized anthocyanidins, flavonols, flavanones, flavonols, flavones, and isoflavones have shown considerable promise as chemopreventive agents. Apigenin (4', 5, 7-trihydroxyflavone), a major plant flavone, possessing antioxidant, anti-inflammatory, and anticancer properties affecting several molecular and cellular targets used to treat various human diseases. Epidemiologic and case-control studies have suggested apigenin reduces the risk of certain cancers. Studies demonstrate that apigenin retain potent therapeutic properties alone and/or increases the efficacy of several chemotherapeutic drugs in combination on a variety of human cancers. Apigenin's anticancer effects could also be due to its differential effects in causing minimal toxicity to normal cells with delayed plasma clearance and slow decomposition in liver increasing the systemic bioavailability in pharmacokinetic studies. Here we discuss the anticancer role of apigenin highlighting its potential activity as a chemopreventive and therapeutic agent. We also highlight the current caveats that preclude apigenin for its use in the human trials.

Intake of Individual Flavonoids and Risk of Carcinogenesis: Overview of Epidemiological Evidence

Several epidemiological findings have demonstrated that specific flavonoids can be responsible for reduction of the risk of certain cancer types. However, these results are still rather limited, inconclusive and controversial. Therefore, in this comprehensive review article the findings reported to date about the associations between dietary intake of individual flavonoid compounds and cancer incidence are compiled and analyzed. Also, the possible reasons for inconsistencies are brought forth and discussed. As diet is a potentially modifiable factor in our behavioral choices, further large-scale prospective studies with longer follow-up times, different populations, various doses and exposure timing as well as diverse well-controlled confounders are highly needed to confirm or disprove the current epidemiological knowledge about the role of flavonoids on cancer risk. Regarding the promising data to date, more research on bioavailability, metabolism and biological action mechanisms of these plant secondary metabolites is also encouraged.

Epidemiological Evidences on Dietary Flavonoids and Breast Cancer Risk: A Narrative Review

Epidemiological studies on associations between intake of flavonoids and breast cancer risk are highly needed to assess the actual effects of flavonoids in humans. Experimental investigations in vitro conditions cannot detect and model the real action of these phytochemicals due to the limitations to consider absorption and metabolic biotransformation as well as several complex interactions. Therefore, the data about association findings between intake of flavonoids and breast cancer risk are compiled and analyzed in the current review by evaluating both the results obtained using food composition databases as well as different biomarkers. Although several case-control studies demonstrate some reduction in breast cancer risk related to high consumption of flavones and flavonols, large-scale prospective cohort studies with follow-up times of many years do not confirm these findings. Intake of isoflavones can be associated with a decrease in breast tumorigenesis only in Asian countries where the consumption of soy foods is high but not among Western women with significantly lower ingestion amounts, suggesting the presence of so-called threshold level of effect. Besides doses, the timing of exposure to isoflavones seems also to be a significant factor as childhood and prepubertal age can be critical periods. Although women may need to consume high amounts of isoflavones typical to Asian diets to gain beneficial effects and protection against mammary carcinogenesis, it is still too early to give any specific recommendations to prevent breast tumors by diet rich in certain flavonoids.

Apigenin overcomes drug resistance by blocking the signal transducer and activator of transcription 3 signaling in breast cancer cells

Drug resistance in chemotherapy is a serious obstacle for the successful treatment of cancer. Drug resistance is caused by various factors, including the overexpression of P-glycoprotein (P-gp, MDR1). The development of new, useful compounds that overcome drug resistance is urgent. Apigenin, a dietary flavonoid, has been reported as an anticancer drug in vivo and in vitro. In the present study, we investigated whether apigenin is able to reverse drug resistance using adriamycin-resistant breast cancer cells (MCF-7/ADR). In our experiments, apigenin significantly decreased cell growth and colony formation in MCF-7/ADR cells and parental MCF-7 cells. This growth inhibition was related to the accumulation of cells in the sub-G₀/G₁ apoptotic population and an increase in the number of apoptotic cells. Apigenin reduced the mRNA expression of multidrug resistance 1 (MDR1) and multidrug resistance-associated proteins (MRPs) in MCF-7/ADR cells. Apigenin also downregulated the expression of P-gp. Apigenin reversed drug efflux from MCF-7/ADR cells, resulting in rhodamine 123 (Rho123) accumulation. Inhibition of drug resistance by apigenin is related to the suppression of the signal transducer and activator of transcription 3 (STAT3) signaling pathway. Apigenin decreased STAT3 activation (p-STAT3) and its nuclear translocation and inhibited the secretion of VEGF and MMP-9, which are STAT3 target genes. A STAT3 inhibitor, JAK inhibitor I and an HIF-1α inhibitor decreased cell growth in MCF-7 and MCF-7/ADR cells. Taken together, these results demonstrate that apigenin can overcome drug resistance.

Association between the dietary inflammatory index and breast cancer in a large Italian case-control study

INTRODUCTION

The putative relationship between diet, including its inflammatory potential, and breast cancer has been studied extensively, but results remain inconsistent. Using data from a large Italian case-control study conducted between 1991 and 1994, we examined the association between the dietary inflammatory index (DII) and odds of breast cancer.

METHODS

DII scores were computed using a validated 78-item food frequency questionnaire. Subjects were 2569 women with incident, histologically confirmed breast cancer and 2588 controls admitted to hospital for acute, non-hormone-related diseases. Odds ratios (ORs) and 95% confidence intervals (CIs) based on continuous and quintiles of DII were estimated by multiple logistic regression adjusting for age, study center, education, BMI, parity, menopausal status, family history of hormone-related cancers, and total energy intake.

RESULTS

Women in quintiles 2, 3, 4 and 5 had ORs of breast cancer of 1.33 (95% CI: 1.11, 1.59), 1.37 (95% CI: 1.13, 1.66), 1.41 (95% CI: 1.15, 1.73), and 1.75 (95% CI: 1.39, 2.21), respectively, compared to women in quintile 1. One-unit increase in DII increased the odds of having breast cancer by 9% (95% CI: 1.05, 1.14).

CONCLUSIONS

A pro-inflammatory diet is associated to increased risk of breast cancer.

The anticancer and antiobesity effects of Mediterranean diet

Cancers have been the leading cause of death worldwide and the prevalence of obesity is also increasing in these few decades. Interestingly, there is a direct association between cancer and obesity. Each year, more than 90,000 cancer deaths are caused by obesity or overweight. The dietary pattern in Crete, referred as the traditional Mediterranean diet, is believed to confer Crete people the low mortality rates from cancers. Nevertheless, the antiobesity effect of the Mediterranean diet is less studied. Given the causal relationship between obesity and cancer, the antiobesity effect of traditional Mediterranean diet might contribute to its anticancer effects. In this regard, we will critically review the anticancer and antiobesity effects of this diet and its dietary factors. The possible mechanisms underlying these effects will also be discussed.

Dietary phytochemical intake from foods and health outcomes: a systematic review protocol and preliminary scoping

INTRODUCTION

Dietary phytochemicals are found in plant-based foods such as fruits, vegetables and grains and may be categorised in a nested hierarchical manner with many hundred individual phytochemicals identified to date. To associate phytochemical intakes with positive health outcomes, a fundamental step is to accurately estimate the dietary phytochemical intake from foods reported. The purpose of this systematic review protocol is to describe the process to be undertaken to summarise the evidence for food-based dietary phytochemical intakes and health outcomes for adults.

METHODS AND ANALYSIS

The review will be undertaken following the PRISMA guidelines and the Cochrane Handbook for Systematic Reviews of Interventions using the Review Manager software. Phytochemical subclasses (phenolic acids, flavanols, etc) will be used to search for relevant studies using the Web of Science and Scopus scientific databases. The retrieved studies will be screened based on inclusion of natural whole food items and health outcomes. Phytochemical studies related to cardiovascular disease, cancer, overweight, glucose tolerance, digestive, reproductive, macular and bone health and mental disorders, fatigue and immunity will be examined based on prior scoping. The evidence will be aggregated by the food types and health outcomes. Comparison of differences in the outcomes for randomised controlled trials and observational studies will be undertaken. The strength of the review lies in its focus on whole food items and health conditions rather than one type of phytochemical related to one single health condition. Subgroup and sensitivity analyses will be conducted where an adequate number of publications are found per phytochemical subclass.

DISSEMINATION

By comparing the outcomes from experimental and observational studies, the review will determine whether the overall conclusions related to the phytochemical subclasses are the same between study types for the identified health conditions. This is useful to public health policymakers and health professionals alike.

TRIAL REGISTRATION NUMBER

#CRD42014015610.

EBV reactivation as a target of luteolin to repress NPC tumorigenesis

Nasopharyngeal carcinoma (NPC) is a malignancy derived from the epithelial cells of the nasopharynx. Although a combination of radiotherapy with chemotherapy is effective for therapy, relapse and metastasis after remission remain major causes of mortality. Epstein-Barr virus (EBV) is believed to be one of causes of NPC development. We demonstrated previously that EBV reactivation is important for the carcinogenesis of NPC. We sought, therefore, to determine whether EBV reactivation can be a target for retardation of relapse of NPC. After screening, we found luteolin is able to inhibit EBV reactivation. It inhibited EBV lytic protein expression and repressed the promoter activities of two major immediate-early genes, Zta and Rta. Furthermore, luteolin was shown to reduce genomic instability induced by recurrent EBV reactivation in NPC cells. EBV reactivation-induced NPC cell proliferation and migration, as well as matrigel invasiveness, were also repressed by luteolin treatment. Tumorigenicity in mice, induced by EBV reactivation, was decreased profoundly following luteolin administration. Together, these results suggest that inhibition of EBV reactivation is a novel approach to prevent the relapse of NPC.

Role of Apigenin in Cancer Prevention via the Induction of Apoptosis and Autophagy

Apigenin (4′,5,7-trihydroxyflavone) is a flavonoid commonly found in many fruits and vegetables such as parsley, chamomile, celery, and kumquats. In the last few decades, recognition of apigenin as a cancer chemopreventive agent has increased. Significant progress has been made in studying the chemopreventive aspects of apigenin both in vitro and in vivo. Several studies have demonstrated that the anticarcinogenic properties of apigenin occur through regulation of cellular response to oxidative stress and DNA damage, suppression of inflammation and angiogenesis, retardation of cell proliferation, and induction of autophagy and apoptosis. One of the most well-recognized mechanisms of apigenin is the capability to promote cell cycle arrest and induction of apoptosis through the p53-related pathway. A further role of apigenin in chemoprevention is the induction of autophagy in several human cancer cell lines. In this review, we discuss the details of apigenin, apoptosis, autophagy, and the role of apigenin in cancer chemoprevention via the induction of apoptosis and autophagy.

Effect of thermal pasteurization and high pressure processing on bioactive properties in strawberry juice

In the current food industry, companies often offer new and revolutionary processing methods that allow to improve food properties. A prominent technology is High Pressure Processing (HPP), a non-thermal technology that arises as an alternative to the traditional thermal pasteurization (TP). With HPP it is possible to obtain food and drinks similar to the raw food while improving important nutritive and functional properties. Since strawberries are very important fruit in the human diet, the aim of this study was to study the effect of HPP and TP on selected qualitative-quantitative parameters of strawberry juices (HPSJ - High Pressure Strawberry Juice/TPSJ - Thermal Pasteurized Strawberry Juice). It seems that strawberries can have a positive effect on human health due to their high content in beneficial nutrients. From monitored parameters, significant differences (p <0.001) were found between juices in the following parameters: antioxidant activity, β-carotene and zeaxanthin content. Higher antioxidant activity (1547.60 ±4.89 mg AA.L-1 FM vs. 1424.72 ±10.66 mg AA.L-1 FM) and zeaxanthin (1.34 ±0.11 μg.mL-1 FM vs. 0.89 ±0.08 μg.mL-1 FM) was found in HPSJ, comparatively to TPSJ. The content of β-carotene was higher in TPSJ (156.28 ±2.13 μg.mL-1 FM) than in HPSJ (122.02 ±4.28 μg.mL-1 FM). Results related to the polyphenols content showed significantly higher values (p ˃0.01) in HPSJ, compared to TPSJ (1100.04 ±17.16 mg GAE.L-1 FM vs. 1002.66 ±17.16 mg GAE.L-1 FM). The difference in the content of lutein (TPSJ 8.84 ±0.57 μg.mL-1 FM; HPSJ 8.17 ±0.13 μg.mL-1 FM) was not significant (p ˃0.05).

Apigenin inhibits the inducible expression of programmed death ligand 1 by human and mouse mammary carcinoma cells

Programmed death ligand 1 (PD-L1) is expressed by many cancer cell types, as well as by activated T cells and antigen-presenting cells. Constitutive and inducible PD-L1 expression contributes to immune evasion by breast cancer (BC) cells. We show here that the dietary phytochemical apigenin inhibited interferon (IFN)-γ-induced PD-L1 upregulation by triple-negative MDA-MB-468 BC cells, HER2(+) SK-BR-3 BC cells, and 4T1 mouse mammary carcinoma cells, as well as human mammary epithelial cells, but did not affect constitutive PD-L1 expression by triple-negative MDA-MB-231 BC cells. IFN-β-induced expression of PD-L1 by MDA-MB-468 cells was also inhibited by apigenin. In addition, luteolin, the major metabolite of apigenin, inhibited IFN-γ-induced PD-L1 expression by MDA-MB-468 cells. Apigenin-mediated inhibition of IFN-γ-induced PD-L1 expression by MDA-MB-468 and 4T1 cells was associated with reduced phosphorylation of STAT1, which was early and transient at Tyr701 and sustained at Ser727. Apigenin-mediated inhibition of IFN-γ-induced PD-L1 expression by MDA-MB-468 cells also increased proliferation and interleukin-2 synthesis by PD-1-expressing Jurkat T cells that were co-cultured with MDA-MB-468 cells. Apigenin therefore has the potential to increase the vulnerability of BC cells to T cell-mediated anti-tumor immune responses.

Tomato as a Source of Carotenoids and Polyphenols Targeted to Cancer Prevention

A diet rich in vegetables has been associated with a reduced risk of many diseases related to aging and modern lifestyle. Over the past several decades, many researches have pointed out the direct relation between the intake of bioactive compounds present in tomato and a reduced risk of suffering different types of cancer. These bioactive constituents comprise phytochemicals such as carotenoids and polyphenols. The direct intake of these chemoprotective molecules seems to show higher efficiencies when they are ingested in its natural biological matrix than when they are ingested isolated or in dietary supplements. Consequently, there is a growing trend for improvement of the contents of these bioactive compounds in foods. The control of growing environment and processing conditions can ensure the maximum potential accumulation or moderate the loss of bioactive compounds, but the best results are obtained developing new varieties via plant breeding. The modification of single steps of metabolic pathways or their regulation via conventional breeding or genetic engineering has offered excellent results in crops such as tomato. In this review, we analyse the potential of tomato as source of the bioactive constituents with cancer-preventive properties and the result of modern breeding programs as a strategy to increase the levels of these compounds in the diet.

Induction of caspase-dependent extrinsic apoptosis by apigenin through inhibition of signal transducer and activator of transcription 3 (STAT3) signalling in HER2-overexpressing BT-474 breast cancer cells

Phytoestrogen intake is known to be beneficial to decrease breast cancer incidence and progression. But its molecular mechanisms of action are still unknown. The present study aimed to examine the effect of apigenin on proliferation and apoptosis in HER2-expressing breast cancer cells. In our experiments, apigenin inhibited the proliferation of BT-474 cells in a dose- and time-dependent manner. Apigenin also inhibited clonogenic survival (anchorage-dependent and -independent) of BT-474 cells in a dose-dependent manner. These growth inhibitions were accompanied with an increase in sub-G0/G1 apoptotic populations. Apigenin-induced extrinsic a caspase-dependent apoptosis up-regulating the levels of cleaved caspase-8 and cleaved caspase-3, and inducing the cleavage of poly (ADP-ribose) polymerase (PARP). Whereas, apigenin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease mitochondrial membrane potential without affecting the levels of B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (BAX). Apigenin reduced the expression of phospho-JAK1, phospho-JAK2 and phospho-STAT3 and decreased signal transducer and activator of transcription 3 (STAT3) dependent luciferase reporter gene activity in BT-474 cells. Apigenin inhibited CoCl2-induced VEGF secretion and decreased the nuclear translocation of STAT3. Our study indicates that apigenin induces apoptosis through inhibition of STAT3 signalling and could serve as a useful compound to prevent or treat HER2-overexpressing breast cancer.