Lycopene, Tomato Products, and Prostate Cancer Incidence: A Review and Reassessment in the PSA Screening Era

Application of ionic liquid ultrasound-assisted extraction (IL-UAE) of lycopene from guava (Psidium guajava L.) by response surface methodology and artificial neural network-genetic algorithm

Lycopene-rich guava (Psidium guajava L.) exhibits significant economic potential as a functional food ingredient, making it highly valuable for the pharmaceutical and agro-food industries. However, there is a need to enhance the extraction methods of lycopene to fully exploit its beneficial uses. In this study, we evaluated various ionic liquids to identify the most effective one for extracting lycopene from guava. Among thirteen ionic liquids with varying carbon chains or anions, 1-butyl-3-methylimidazolium chloride demonstrated the highest productivity. Subsequently, a single-factor experiment was employed to test the impact of several parameters on the efficiency of lycopene extraction using this selected ionic liquid. These parameters included extraction time, ultrasonic power, liquid-solid ratio, concentration of the ionic liquid, as well as material particle size. Moreover, models of artificial neural networks using genetic algorithms (ANN-GA) and response surface methodology (RSM) were employed to comprehensively assess the first four key parameters. The optimized conditions for ionic liquid ultrasound-assisted extraction (IL-UAE) were determined as follows: 33 min of extraction time, 225 W of ultrasonic power, 22 mL/g of liquid-solid ratio, 3.0 mol/L of IL concentration, and extraction cycles of three. Under these conditions, lycopene production reached an impressive yield of 9.35 ± 0.36 mg/g while offering advantages such as high efficiency, time savings, preservation benefits, and most importantly environmental friendliness.

Walk More, Eat Less, Don't Stress

Unhealthy diet, obesity, lack of physical activity, and psychologic stress are associated with increased inflammation, oxidative stress, insulin resistance, and DNA methylation, which are the main mechanisms of chronic diseases such as cancer, hypertension, diabetes, cardiovascular disease, and Alzheimer's disease. It has recently been found that healthy diet and physical activity can reduce inflammatory markers and improve insulin sensitivity resulting in better survivorship outcomes in patients with prostate cancer. An "anti-inflammatory" lifestyle, including physical activity, healthy body weight, healthy diet, and stress reduction, has been associated with decreased cancer risk and progression. Epigenetic changes due to DNA methylation and altered gene expression associated with unhealthy lifestyle can be modulated by healthy behaviors. National Center for Complementary and Integrative Health (NCCIH) focuses on healthy lifestyle, and it supports research on psychologic and physical approaches including dietary supplements and plant-based products, as well as mind and body approaches, such as yoga, massage, meditation, mindfulness-based stress reduction, and acupuncture. See related article by Langlais et al., p. 1760.

Chemopreventive Potential of Dietary Nanonutraceuticals for Prostate Cancer: An Extensive Review

There are more than two hundred fifty different types of cancers, that are diagnosed around the world. Prostate cancer is one of the suspicious type of cancer spreading very fast around the world, it is reported that in 2018, 29430 patients died of prostate cancer in the United State of America (USA), and hence it is expected that one out of nine men diagnosed with this severe disease during their lives. Medical science has identified cancer at several stages and indicated genes mutations involved in the cancer cell progressions. Genetic implications have been studied extensively in cancer cell growth. So most efficacious drug for prostate cancer is highly required just like other severe diseases for men. So nutraceutical companies are playing major role to manage cancer disease by the recommendation of best natural products around the world, most of these natural products are isolated from plant and mushrooms because they contain several chemoprotective agents, which could reduce the chances of development of cancer and protect the cells for further progression. Some nutraceutical supplements might activate the cytotoxic chemotherapeutic effects by the mechanism of cell cycle arrest, cell differentiation procedures and changes in the redox states, but in other, it also elevate the levels of effectiveness of chemotherapeutic mechanism and in results, cancer cell becomes less reactive to chemotherapy. In this review, we have highlighted the prostate cancer and importance of nutraceuticals for the control and management of prostate cancer, and the significance of nutraceuticals to cancer patients during chemotherapy.

Tomatoes, Lycopene, and Prostate Cancer: What Have We Learned from Experimental Models?

Human epidemiology suggests a protective effect of tomatoes or tomato phytochemicals, such as lycopene, on prostate cancer risk. However, human epidemiology alone cannot reveal causal relations. Laboratory animal models of prostate cancer provide opportunities to investigate hypotheses regarding dietary components in precisely controlled, experimental systems, contributing to our understanding of diet and cancer risk relations. We review the published studies evaluating the impact of tomatoes and/or lycopene in preclinical models of prostate carcinogenesis and tumorigenesis. The feeding of tomatoes or tomato components demonstrates anti-prostate cancer activity in both transplantable xenograft models of tumorigenesis and models of chemically- and genetically-driven carcinogenesis. Feeding pure lycopene shows anticancer activity in most studies, although outcomes vary by model system, suggesting that the impact of pure lycopene can depend on dose, duration, and specific carcinogenic processes represented in different models. Nonetheless, studies with the transgenic adenocarcinoma of the mouse prostate (TRAMP) model of carcinogenesis typically demonstrate similar bioactivity to that of tomato feeding. In general, interventions that commence earlier in carcinogenesis and are sustained tend to be more efficacious. Accumulated data suggest that lycopene is one, but perhaps not the only, anticancer bioactive compound in tomatoes. Although it is clear that tomatoes and lycopene have anti-prostate cancer activity in rodent models, major knowledge gaps remain in understanding dose-response relations and molecular mechanisms of action. Published and future findings from rodent studies can provide guidance for translational scientists to design and execute informative human clinical trials of prostate cancer prevention or in support of therapy.

Tomatoes: An Extensive Review of the Associated Health Impacts of Tomatoes and Factors That Can Affect Their Cultivation

Simple Summary

The research outlined in this review paper discusses potential health benefits associated with a diet enriched with tomatoes and tomato products. This includes details of previous studies investigating the anticancer properties of tomatoes, protection against cardiovascular and neurodegenerative diseases and diabetes, maintenance of a healthy gut microbiome, and improved skin health, fertility, immune response, and exercise recovery. The specific parts of a tomato fruit that contribute these health benefits are also outlined. The potential disadvantages to a tomato-rich diet are detailed, especially the consumption of supplements that contain compounds found in tomatoes, such as lycopene. This review also discusses how the cultivation of tomato plants can affect the nutritional value of the fruit harvested. Different environmental growing conditions such as light intensity, growing media, and temperature are explained in terms of the impact they have on the quality of fruit, its nutrient content, and hence the potential health benefits acquired from eating the fruit.

Abstract

This review outlines the health benefits associated with the regular consumption of tomatoes and tomato products. The first section provides a detailed account of the horticultural techniques that can impact the quality of the fruit and its nutritional properties, including water availability, light intensity, temperature, and growing media. The next section provides information on the components of tomato that are likely to contribute to its health effects. The review then details some of the health benefits associated with tomato consumption, including anticancer properties, cardiovascular and neurodegenerative diseases and skin health. This review also discusses the impact tomatoes can have on the gut microbiome and associated health benefits, including reducing the risk of inflammatory bowel diseases. Other health benefits of eating tomatoes are also discussed in relation to effects on diabetes, the immune response, exercise recovery, and fertility. Finally, this review also addresses the negative effects that can occur as a result of overconsumption of tomato products and lycopene supplements.

Review On Documented Medicinal Plants Used For The Treatment Of Cancer

Background:

Cancer is a frightful disease and it is the second leading cause of death worldwide. Naturally derived compounds are gaining interest of research workers as they have less toxic side effects as compared to currently used treatments such as chemotherapy. Plants are the pool of chemical compounds which provides a promising future for research on cancer.

Objective:

This review paper provides updated information gathered on medicinal plants and isolated phytoconstituents used as anticancer agents and summarises the plant extracts and their isolated chemical constituents exhibiting anticancer potential on clinical trials.

Methods:

An extensive bibliographic investigation was carried out by analysing worldwide established scientific databases like SCOPUS, PUBMED, SCIELO, ScienceDirect, Springerlink, Web of Science, Wiley, SciFinder and Google Scholar etc. In next few decades, herbal medicine may become a new epoch of medical system.

Results:

Many researches are going on medicinal plants for the treatment of cancer but it is a time to increase further experimental studies on plant extracts and their chemical constituents to find out their mechanism of action at molecular level.

Conclusion:

The article may help many researchers to start off further experimentation that might lead to the drugs for the cancer treatment.

Biochemical composition of tomato fruits of various colors

Tomato (Lycopersicon esculentum Mill.) is an economically important and widely cultivated vegetable crop that is consumed both fresh and processed. The nutritional value of tomato fruits is related to the content of carotenoids, polyphenols, sugars, organic acids, minerals and vitamins. Currently, there is a growing interest in the qualitative and quantitative increase in the content of health-promoting compounds in tomato fruits. VIR Lycopersicon (Tourn.) Mill. genetic resources collection includes 7678 accessions of one cultivated and nine wild species, which in turn provides ample opportunities for searching for information on the variability of the content of biologically active substances and searching for sources with a high content of them in the gene pool. Our work presents the results of the study of 70 accessions of cultivated and wild tomato on the main biochemical characteristics: the content of dry matter, ascorbic acid, sugars, carotenoids, chlorophylls and anthocyanins. As the basis for the selection of accessions for the study, accessions with various colors of fruits, including new accessions with varying content of anthocyanin, were taken. As a result of this study, the amplitude of variability in the content of dry matter (3.72–8.88 and 9.62–11.33 %), sugars (1.50–5.65 and 2.20–2.70 %), ascorbic acid (12.40–35.56 and 23.62– 28.14 mg/100 g), titratable acidity (0.14–0.46 and 0.33–0.48 %), chlorophylls (0.14–5.11 and 2.95–4.57 mg/100 g), carotenoids (0.97–99.86 and 1.03–10.06 mg/100 g) and anthocyanins (3.00–588.86 and 84.31–152.71 mg/100 g) in the fruits of cultivated and wild tomatoes, respectively, was determined. We have determined correlations between the content of dry matter and monosaccharides (r = 0.40, p ≤ 0.05), total sugars (r = 0.37, p ≤ 0.05) and ascorbic acid (r = 0.32, p ≤ 0.05); the content of ascorbic acid and carotenoids (r = 0.25, p ≤ 0.05). A high dependence of the content of chlorophyll a and b among themselves (r = 0.89, p ≤ 0.05), as well as between the content of chlorophyll b and anthocyanins (r = 0.47, p ≤ 0.05), the content of β-carotene (r = 0.26, p ≤ 0.05) and the content of monosaccharides (r = –0.29, p ≤ 0.05) has been noted. We have identif ied tomato accessions with a high content of individual chemical substances, as well as with a complex of traits that can be used as sources in breeding for a high content of dry matter, sugars, ascorbic acid, pigments and anthocyanins.

Pertinence of nutriments for a stalwart body

Nutrition plays a significant role in the prevention and treatment of common diseases. Some superb dietary choices such as functional foods and nutriments can surely help fight against certain diseases and provide various advantages to an individual's health. Plants have been regarded as a primary source of highly effective conventional drugs leading to the development of potential novel agents, which may boost the treatment. Growing demand for functional foods acts as an aid for the producers to expand in agriculture and pave the way for innovation and research by the nutraceutical industry. The given review highlights how various functional foods such as tomatoes, chocolates, garlic and flaxseed are currently being defined, their sources, benefit in treating various ailments and the challenges with their use.

Anticancer Potential of Betulonic Acid Derivatives

Clinical trials have evidenced that several natural compounds, belonging to the phytochemical classes of alkaloids, terpenes, phenols and flavonoids, are effective for the management of various types of cancer. Latest research has proven that natural products and their semisynthetic variants may serve as a starting point for new drug candidates with a diversity of biological and pharmacological activities, designed to improve bioavailability, overcome cellular resistance, and enhance therapeutic efficacy. This review was designed to bring an update regarding the anticancer potential of betulonic acid and its semisynthetic derivatives. Chemical derivative structures of betulonic acid including amide, thiol, and piperidine groups, exert an amplification of the in vitro anticancer potential of betulonic acid. With the need for more mechanistic and in vivo data, some derivatives of betulonic acids may represent promising anticancer agents.

The potential health benefits of dietary natural plant products in age related eye diseases

In the past decade, there has been a tremendous increase in the number of cases of age-related eye diseases such as age-related macular degeneration (AMD), cataract, diabetic retinopathy and glaucoma. These diseases are the leading causes of visual impairment and blindness all over the world and are associated with many pathological risk factors such as aging, pollution, high levels of glucose (hyperglycaemia), high metabolic rates, and light exposure. These risk factors lead to the generation of uncontrollable reactive oxygen species (ROS), which causes oxidative stress. Oxidative stress plays a crucial role in the pathogenesis of age-related eye diseases through the activation of nuclear factor kappa B (NF-κB), vascular endothelial growth factor (VEGF), and lipid peroxidation, which leads to the production of inflammatory cytokines, angiogenesis, protein and DNA damages, apoptosis that causes macular degeneration (AMD), cataract, diabetic retinopathy and glaucoma. This review provides updated information on the beneficial effects of dietary natural plant products (DPNPs) against age-related eye diseases. In this review, supplementation of DPNPs demonstrated preventive and therapeutic effects on people at risk of or with age-related eye diseases due to their capacity to scavenge free radicals, ameliorate inflammatory molecules, neutralize the oxidation reaction that occurs in photoreceptor cells, decrease vascular endothelial growth factor and the blood-retinal barrier and increase the antioxidant defence system. However, further experiments and clinical trials are required to establish the daily doses of DPNPs that will safely and effectively prevent age-related eye diseases.

Dried Fruit Intake and Cancer: A Systematic Review of Observational Studies

Insufficient intake of total fruits and vegetables is linked to an increased cancer risk, but the relation is not understood for dried fruits. Dried fruits are generally perceived, by both consumers and researchers, as a less attractive but shelf-stable equivalent to fresh fruits and constitute a small but significant proportion of modern diets. Chemical compositions of raw and dried fruits, however, may differ substantially. Several clinical and laboratory intervention studies have reported the protective effects of dehydrated fruits against the progression of some cancers and the modulating effects of dried fruits on common cancer risk factors. In this systematic review, we identified, summarized, and critically evaluated 9 prospective cohort and 7 case-control studies that examined the relations between traditional dried fruit (raisins, prunes, dates) consumption and cancer risk in humans. Prospective cohort studies determined that significant reductions in relative risk of precancerous colorectal polyps, incidence of prostate cancer, or mortality from pancreatic cancer, by, respectively, 24%, 49%, and 65%, were associated with 3-5 or more servings of dried fruits per week. Selected case-control studies revealed inverse associations between dried fruit intake and risk of cancer as well. The reported associations were comparable to or stronger than those observed for total or raw fruits. Although the small number and high heterogeneity impede meta-analysis of these studies, we conclude that currently available data provide some initial evidence that consumption of dried fruits may be associated with a lower cancer incidence or mortality in populations. The data suggest that higher intake of raisins and other dried fruits may be important in the prevention of cancers of the digestive system. Because only a limited number of health outcome and dried fruit intake relations have been evaluated in prospective studies to date, reanalyzing existing high-quality epidemiological data may expand the knowledge base.

Effect of green tea and lycopene on the insulin-like growth factor system: the ProDiet randomized controlled trial

Whether prostate cancer (PCa) may be preventable by dietary interventions can be assessed in randomized trials using intermediate biomarkers of cancer risk or progression. We investigated whether lycopene or green tea modify circulating insulin-like growth factor (IGF) peptides in men at increased risk of PCa. Participants (aged 50-69 years) in one centre in the UK wide PCa testing and treatment trial (ProtecT) with prostate specific antigen between 2.0 and 2.95 ng/ml or negative biopsies, were randomized to daily lycopene (n = 44 assigned 15 mg capsules/day; 44 assigned a lycopene-rich diet; 45 assigned placebo) and green tea (n = 45 assigned 600 mg/day epigallocatechin gallate; 45 assigned green tea drink; 43 assigned placebo) for 6 months. The interventions significantly elevated the primary outcomes, serum epigallocatechin gallate and lycopene at 6 months of follow-up. We report here an exploratory analysis in which serum IGF-I, IGF-II, IGF binding protein (BP)-2 and IGFBP-3 were measured at baseline and 6 months of postintervention. A total of 133 men were randomized (34% of eligible men approached) and 130 had follow-up IGF peptides (98%). In intention-to-treat analyses, there was only weak evidence that lycopene or green tea influenced some aspects of serum IGF-I, IGF-II, IGFBP-2 or IGFBP-3. In men randomized to lycopene supplements, IGFBP-2 was nonsignificantly (50.9 ng/ml; 95% confidence interval: -51.2-152.9, P = 0.3) higher in comparison to placebo, whereas in men randomized to green tea supplements, IGFBP-3 was nonsignificantly (205.2 ng/ml; 95% confidence interval: -583.3-172.9, P = 0.3) lower than with placebo. In this small, pilot randomized controlled trial, there was little evidence that lycopene or green tea interventions influenced serum levels of IGF-I, IGF-II, IGFBBP-3 and IGFBP-2. However, the effects were imprecisely estimates and some observed trends may justify larger trials.

Cancer and Mediterranean Diet: A Review

The Mediterranean diet is considered one of the most worldwide healthy dietary patterns thanks to a combination of foods rich mainly in antioxidants and anti-inflammatory nutrients. Many studies have demonstrated a strong and inverse relationship between a high level of Mediterranean diet adherence and some chronic diseases (such as cardiovascular diseases, diabetes, etc.) and cancer. Given its protective effects in reducing oxidative and inflammatory processes of cells and avoiding DNA damages, cell proliferation, and their survival, angiogenesis, inflammations and metastasis, the Mediterranean diet is considered a powerful and manageable method to fight cancer incidence. The aim of this narrative review was to determine the magnitude of interaction between the Mediterranean diet and more widespread types of cancer so as to give a first and useful overview on this relationship identifying, with a nutritional approach, those nutrients of Mediterranean diet able to reduce cancer incidence.

Analysis of Tomato Carotenoids: Comparing Extraction and Chromatographic Methods

Background: Tomatoes (Solanum lycopersicum) are an economically and nutritionally important crop colored by carotenoids such as lycopene and β-carotene. Market diversification and interest in the health benefits of carotenoids has created the desire in plant, food, and nutritional scientists for improved extraction and quantification protocols that avoid the analytical bottlenecks caused by current methods. Objective: Our objective was to compare standard and rapid extraction as well as chromatographic separation methods for tomato carotenoids. Method: Comparison was based on accuracy and the ability to discriminate between alleles and genetic backgrounds. Estimates of the contribution to variance in the presence of genetic and environmental effects were further used for comparison. Selections of cherry and processing tomatoes with varying carotenoid profiles were assessed using both established extraction and HPLC-diode array detector (HPLC-DAD) methods and rapid extraction and ultra-HPLC-DAD (UHPLC-DAD) protocols. Results: Discrimination of alleles in samples extracted rapidly (<5 min/sample) was similar to samples extracted using a standard method (10 min/sample), although carotenoid concentrations were lower due to reduced extraction efficiency. Quantification by HPLC-DAD (21.5 min/sample) and UHPLC-DAD (4.2 min/sample) were comparable, but the UHPLC-DAD method could not separate all carotenoids and isomers of tangerine tomatoes. Random effects modeling indicated that extraction and chromatographic methods explained a small proportion of variance compared with genetic and environmental sources. Conclusions: The rapid extraction and UHPLC-DAD methods could enhance throughput for some applications compared with standard protocols.

Diet and longevity: The effects of traditional eating habits on human lifespan extension

Since the dawn of time human beings have been trying to improve the quality of the existence and extend their lifespan. Genetic, environmental, behavioral and dietary factors influence the pathways that regulate aging and life expectancy, thus rendering longevity a very complex phenomenon. Although a long-lived elixir has not yet been found, physicians and scientists agree that nutrition has a major impact on the overall mortality and morbidity, hence becoming the subject of a widespread scientific research. This review describes, analyzes and compares the effects of different types of diets in reducing the onset of typical Western countries non-communicable diseases (NCDs) (cardiovascular diseases, tumors, chronic respiratory diseases, diabetes, etc.), thus increasing the average lifespan. It will first depict the most relevant characteristics, nutraceutical properties and effects on the populations of the Mediterranean, Japanese, Vegetarian and New Nordic Diet. Finally, it will describe the impact of different dietary restrictions in modulating the genetic pathways that regulate metabolism and aging. Overall, this work reinforces the evidence that specific eating habits, in addition to healthy and active lifestyles, are crucial to increase people’s health span and to achieve an optimal longevity.

A Pooled Analysis of 15 Prospective Cohort Studies on the Association between Fruit, Vegetable, and Mature Bean Consumption and Risk of Prostate Cancer

Background: Relationships between fruit, vegetable, and mature bean consumption and prostate cancer risk are unclear.Methods: We examined associations between fruit and vegetable groups, specific fruits and vegetables, and mature bean consumption and prostate cancer risk overall, by stage and grade, and for prostate cancer mortality in a pooled analysis of 15 prospective cohorts, including 52,680 total cases and 3,205 prostate cancer-related deaths among 842,149 men. Diet was measured by a food frequency questionnaire or similar instrument at baseline. We calculated study-specific relative risks using Cox proportional hazards regression, and then pooled these estimates using a random effects model.Results: We did not observe any statistically significant associations for advanced prostate cancer or prostate cancer mortality with any food group (including total fruits and vegetables, total fruits, total vegetables, fruit and vegetable juice, cruciferous vegetables, and tomato products), nor specific fruit and vegetables. In addition, we observed few statistically significant results for other prostate cancer outcomes. Pooled multivariable relative risks comparing the highest versus lowest quantiles across all fruit and vegetable exposures and prostate cancer outcomes ranged from 0.89 to 1.09. There was no evidence of effect modification for any association by age or body mass index.Conclusions: Results from this large, international, pooled analysis do not support a strong role of collective groupings of fruits, vegetables, or mature beans in prostate cancer.Impact: Further investigation of other dietary exposures, especially indicators of bioavailable nutrient intake or specific phytochemicals, should be considered for prostate cancer risk. Cancer Epidemiol Biomarkers Prev; 26(8); 1276-87. ©2017 AACR.

Increased dietary and circulating lycopene are associated with reduced prostate cancer risk: a systematic review and meta-analysis

BACKGROUND

Prostate cancer (PCa) is the fifth leading cause of cancer-related deaths worldwide. Many epidemiological studies have investigated the association between prostate cancer and lycopene, however, results have been inconsistent. This study aims to determine the impact of dietary and circulating concentrations of lycopene on PCa risk and to investigate potential dose-response associations.

METHODS

We conducted a systematic review and dose-response meta-analysis for the for the association between dietary and circulating lycopene and PCa risk. Eligible studies were published before 1 December 2016 and were identified from PubMed, Web of Science and the Cochrane Library. We estimated pooled relative risk ratios (RR) and 95% confidence intervals (CI) using random and fixed effects models. Linear and nonlinear dose-response relationships were also evaluated for PCa risk.

RESULTS

Forty-two studies were included in the analysis, which included 43 851 cases of PCa reported from 692 012 participants. Both dietary intake (RR=0.88, 95% CI: 0.78-0.98, P=0.017) and circulating concentrations (RR=0.88, 95% CI: 0.79-0.98, P=0.019) of lycopene were significantly associated with reduced PCa risk. Sensitivity analyses within the dose-response analysis further revealed a significant linear dose-response for dietary lycopene and PCa risk such that PCa decreased by 1% for every additional 2 mg of lycopene consumed (P=0.026). Additionally, PCa risk decreased by 3.5 to 3.6% for each additional 10 μgdl^-1 of circulating lycopene in the linear and nonlinear models respectively (p_linear=0.004, p_nonlinear=0.006). While there were no associations between lycopene and advanced PCa, there was a trend for protection against PCa aggressiveness (RR=0.74, 95% CI: 0.55-1.00, P=0.052).

CONCLUSIONS

Our data demonstrate that higher dietary and circulating lycopene concentrations are inversely associated with PCa risk. This was accompanied by dose-response relationships for dietary and circulating lycopene. However, lycopene was not associated with a reduced risk of advanced PCa. Further studies are required to determine the mechanisms underlying these associations.

Carotenoid deposition in plant and animal foods and its impact on bioavailability

Over the past decades, an enormous body of literature dealing with the natural deposition of carotenoids in plant- and animal-based foods has accumulated. Prominent examples are the large solid-crystalline aggregates in carrots and tomatoes or the lipid-dissolved forms in dairy products and egg yolk. Latest research has identified lipid-dissolved forms in a rare number of plant foods, such as tangerine tomatoes and peach palm fruit (Bactris gasipaes Kunth). In addition, liquid-crystalline forms were assumed in so-called tubular chromoplasts of numerous fruits, e.g., in papaya, mango, and bell pepper. The bioavailability of carotenoids from fresh and processed foods strongly depends on their genuine deposition form, since their effective absorption to the human organism requires their liberation from the food matrix and subsequent solubilization into mixed micelles in the small intestine. Consequently, a broad overview about the natural array of carotenoid deposition forms should be helpful to better understand and modulate their bioavailability from foods. Furthermore, naturally highly bioavailable forms may provide biomimetic models for the improved formulation of carotenoids in food supplements. Therefore, this review paper presents scientific evidence from human intervention studies associating carotenoid deposition forms with their bioavailability, thus suggesting novel technological and dietary strategies for their enhanced absorption.

Role of phytochemicals in the modulation of miRNA expression in cancer

MicroRNAs (miRNAs) are single-stranded non-coding endogenous RNAs. They act as tumour suppressors and oncogenes in tumorigenesis. Phytochemicals have a unique capability to regulate the expression of miRNAs in various cancers.

Plasma Lycopene Is Associated with Pizza and Pasta Consumption in Middle-Aged and Older African American and White Adults in the Southeastern USA in a Cross-Sectional Study

BACKGROUND

The role of dietary lycopene in chronic disease prevention is not well known.

METHODS

This study examined intake of lycopene and other antioxidants from lycopene-rich foods (e.g., pizza and pasta) simultaneously with plasma levels of lycopene and other antioxidants in a representative cross-sectional sample (187 Blacks, 182 Whites, 40-79 years old) from the Southern Community Cohort Study (SCCS). The SCCS is an ongoing study conducted in populations at high risk for chronic diseases living in Southeastern United States. Dietary intake was assessed using a validated food frequency questionnaire (FFQ), and plasma levels of lycopene and other antioxidants were measured at baseline (2002-2005). The participants were classified into tertiles according to consumption of pizza and pasta food groups.

RESULTS

Lycopene dietary intake and plasma lycopene concentrations were significantly higher in the highest (tertile 3) compared to tertiles 1 and 2 (both P < 0.01). Total energy intake ranged from 1964.3 ± 117.1 kcal/day (tertile 1) to 3277.7 ± 115.8 kcal/day (tertile 3) (P<0.0001). After adjusting for age and energy intake, total dietary fat, saturated fatty acids, trans-fatty acids, and sodium intakes were significantly higher in tertile 3 than tertiles 2 and 1 (all P <0.01). Vitamin C intake was significantly lower in tertile 3 than tertiles 1 and 2 (P = 0.003). Except for γ-tocopherol being higher in tertile 3 than tertiles 1 and 2 (P = 0.015), the plasma concentrations of antioxidants were lower in tertile 3 than tertiles 1 and 2 (β-carotene, α-carotene, lutein and zeaxanthin, all P<0.05).

CONCLUSIONS

In the SCCS population, pizza and pasta were the main sources of dietary lycopene and their intake was associated with plasma lycopene concentration. Diets with frequent pizza and pasta consumption were high in energy, saturated fatty acids, trans-fatty acids, sodium and low in other antioxidants. Future studies of lycopene as a protective dietary factor against chronic disease should consider the overall nutritional quality of lycopene-containing foods.

A Phase II Randomized Trial of Lycopene-Rich Tomato Extract Among Men with High-Grade Prostatic Intraepithelial Neoplasia

A diverse body of evidence suggests that lycopene might inhibit prostate cancer development. We conducted a 6-mo repeat biopsy randomized trial among men with high-grade prostatic intraepithelial neoplasia (HGPIN). Here we report results for serum lycopene, prostate specific antigen (PSA) and insulin-like growth factor (IGF) proteins, histopathological review, and tissue markers for proliferation [minichromosome maintenance protein 2 (MCM-2)] and cell cycle inhibition (p27). Participants consumed placebo or tomato extract capsules containing 30 mg/day lycopene. Pre- and posttreatment biopsies were immunostained and digitally scored. Serum lycopene was determined by LC-MS-MS. In secondary analyses, pathologists blindly reviewed each biopsy to score histological features. Fifty-eight men completed the trial. Serum lycopene increased 0.55 μmol/L with treatment and declined 0.29 μmol/L with placebo. We observed no meaningful differences in PSA, IGF-1, or IGF binding protein 3 concentrations between groups, nor any differences in expression of MCM-2 or p27 in epithelial nuclei. Prevalences of cancer, HGPIN, atrophy, or inflammation posttreatment were similar; however, more extensive atrophy and less extensive HGPIN was more common in the lycopene group. Despite large differences in serum lycopene following intervention, no treatment effects were apparent on either the serum or benign tissue endpoints. Larger studies are warranted to determine whether changes observed in extent of HGPIN and focal atrophy can be replicated.

A Common Variant in the SETD7 Gene Predicts Serum Lycopene Concentrations

Dietary intake and higher serum concentrations of lycopene have been associated with lower incidence of prostate cancer and other chronic diseases. Identifying determinants of serum lycopene concentrations may thus have important public health implications. Prior studies have suggested that serum lycopene concentrations are under partial genetic control. The goal of this research was to identify genetic predictors of serum lycopene concentrations using the genome-wide association study (GWAS) approach among a sample of 441 Old Order Amish adults that consumed a controlled diet. Linear regression models were utilized to evaluate associations between genetic variants and serum concentrations of lycopene. Variant rs7680948 on chromosome 4, located in the intron region of the SETD7 gene, was significantly associated with serum lycopene concentrations (p = 3.41 × 10⁻⁹). Our findings also provided nominal support for the association previously noted between SCARB1 and serum lycopene concentrations, although with a different SNP (rs11057841) in the region. This study identified a novel locus associated with serum lycopene concentrations and our results raise a number of intriguing possibilities regarding the nature of the relationship between SETD7 and lycopene, both of which have been independently associated with prostate cancer. Further investigation into this relationship might help provide greater mechanistic understanding of these associations.

MicroRNA-let-7f-1 is induced by lycopene and inhibits cell proliferation and triggers apoptosis in prostate cancer

Previous studies have suggested that lycopene has cytotoxic effects in a variety of types of human cancer. An improved understanding of the mechanisms underlying the anticancer effects of lycopene may provide novel therapeutic targets for cancer treatment. PC3 cells were treated with different concentrations of lycopene for 24 and 48 h, the level of protein kinase B (AKT2) was detected by reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) and western blotting. Additionally, the expression levels of microRNA (miR)‑let‑7f‑1 were measured using RT‑qPCR. miR‑let‑7f‑1 function was analyzed using cell proliferation and apoptosis assays in gain‑ and loss‑of‑function experiments. It was observed that lycopene downregulated the expression of AKT2 and upregulated the expression of miR‑let‑7f‑1 in PC3 cells. Re‑introduction of miR‑let‑7f‑1 into PC3 cells was able to inhibit cell proliferation and induce apoptosis. Further investigation indicated that miR‑let‑7f‑1 targeted AKT2 in PC3 cells and upregulation of AKT2 could attenuate the effects induced by miR‑let‑7f‑1. The results of the current study indicate that miR‑let‑7f‑1 is involved in the anticancer effects of lycopene and serves an important role in the inhibition of prostate cancer progression through the downregulation of AKT2.

A comparison of plasma and prostate lycopene in response to typical servings of tomato soup, sauce or juice in men before prostatectomy

Tomato product consumption and estimated lycopene intake are hypothesised to reduce the risk of prostate cancer. To define the impact of typical servings of commercially available tomato products on resultant plasma and prostate lycopene concentrations, men scheduled to undergo prostatectomy (n 33) were randomised either to a lycopene-restricted control group ( < 5 mg lycopene/d) or to a tomato soup (2-2¾ cups prepared/d), tomato sauce (142-198 g/d or 5-7 ounces/d) or vegetable juice (325-488 ml/d or 11-16·5 fluid ounces/d) intervention providing 25-35 mg lycopene/d. Plasma and prostate carotenoid concentrations were measured by HPLC. Tomato soup, sauce and juice consumption significantly increased plasma lycopene concentration from 0·68 (sem 0·1) to 1·13 (sem 0·09) μmol/l (66 %), 0·48 (sem 0·09) to 0·82 (sem 0·12) μmol/l (71 %) and 0·49 (sem 0·12) to 0·78 (sem 0·1) μmol/l (59 %), respectively, while the controls consuming the lycopene-restricted diet showed a decline in plasma lycopene concentration from 0·55 (sem 0·60) to 0·42 (sem 0·07) μmol/l ( - 24 %). The end-of-study prostate lycopene concentration was 0·16 (sem 0·02) nmol/g in the controls, but was 3·5-, 3·6- and 2·2-fold higher in tomato soup (P= 0·001), sauce (P= 0·001) and juice (P= 0·165) consumers, respectively. Prostate lycopene concentration was moderately correlated with post-intervention plasma lycopene concentrations (r 0·60, P =0·001), indicating that additional factors have an impact on tissue concentrations. While the primary geometric lycopene isomer in tomato products was all-trans (80-90 %), plasma and prostate isomers were 47 and 80 % cis, respectively, demonstrating a shift towards cis accumulation. Consumption of typical servings of processed tomato products results in differing plasma and prostate lycopene concentrations. Factors including meal composition and genetics deserve further evaluation to determine their impacts on lycopene absorption and biodistribution.

Oxidative stress-related genetic variants, pro- and antioxidant intake and status, and advanced prostate cancer risk

BACKGROUND

Increased oxidative stress has been linked to prostate cancer. We investigated oxidative stress-related genetic variants in relation to advanced prostate cancer risk and examined potential interactions with pro- and antioxidant exposures.

METHODS

A case-cohort analysis was conducted in the prospective Netherlands Cohort Study, which included 58,279 men ages 55 to 69 years. Cohort members completed a baseline questionnaire and provided toenail clippings, which were used to isolate DNA. Advanced prostate cancer cases were identified during 17.3 years of follow-up. The analysis included 14 genetic variants and 11 exposures. Cox regression models were used for analysis and FDR Q-values were calculated.

RESULTS

Complete genotyping data were available for 952 cases and 1,798 subcohort members. CAT rs1001179 was associated with stage III/IV and stage IV prostate cancer risk, with HRs per minor allele of 1.16 [95% confidence intervals (CI), 1.01-1.33; P = 0.032] and 1.25 (95% CI, 1.07-1.46; P = 0.006), respectively. We tested 151 gene-environment interactions in relation to both stage III/IV and IV prostate cancer risk. Seven interactions were statistically significant after adjusting for multiple testing (FDR Q-value <0.20); for stage III/IV prostate cancer, these involved intake of β-carotene (GPX1 rs17650792, hOGG1 rs1052133) and heme iron (GPX1 rs1800668 and rs3448), and for stage IV prostate cancer, these involved intake of catechin (SOD2 rs4880) and heme iron (hOGG1 rs1052133, SOD1 rs10432782).

CONCLUSION

This study of advanced prostate cancer risk showed a marginal association with a CAT polymorphism and seven novel gene-environment interactions in the oxidative stress pathway.

IMPACT

Oxidative stress-related genes and exposures may have a joint effect on advanced prostate cancer. Cancer Epidemiol Biomarkers Prev; 24(1); 178-86. ©2014 AACR.

Dietary factors and risk for advanced prostate cancer

Prostate cancer is the second most common cancer among men worldwide. Although some nutrients have been linked to the development of total prostate cancer, it remains unclear whether these nutrients modulate the risk of its clinically significant form - advanced tumor. Therefore, this study sought to perform a systematic review of the literature on this topic. The papers reviewed were identified from PubMed using keywords diet and advanced, metastatic, or lethal prostate cancer. A total of 46 papers published until September 2012 met our eligibility criteria and thus were evaluated in this review. Epidemiologic studies have shown that, overall, the habitual consumption of a diet high in saturated fat, well-done meats, and calcium is associated with an increased risk for advanced prostate cancer. An inconsistent association was observed for intake of total meat, fruits, and vegetables. Although most case-control studies suggest that intake of these nutrients or foods significantly alters advanced prostate cancer risk, cohort studies yielded mixed results. No apparent effect of fish and zinc intake on advanced prostate cancer was found in most epidemiologic studies. Epidemiologic studies conducted to date have revealed that some dietary factors modulate the risk for advanced prostate cancer. If these findings are confirmed by more adequately powered epidemiologic studies, especially prospective cohort studies that measure the nutrients and their biochemical indicators, the risk of advanced prostate cancer, which is fatal and thus clinically significant, may be reduced by dietary modification or chemoprevention.

Anti-proliferative and apoptosis-inducing activity of lycopene against three subtypes of human breast cancer cell lines

Although lycopene, a major carotenoid component of tomatoes, has been suggested to attenuate the risk of breast cancer, the underlying preventive mechanism remains to be determined. Moreover, it is not known whether there are any differences in lycopene activity among different subtypes of human breast cancer cells. Using ER/PR positive MCF-7, HER2-positive SK-BR-3 and triple-negative MDA-MB-468 cell lines, we investigated the cellular and molecular mechanism of the anticancer activity of lycopene. Lycopene treatment for 168 consecutive hours exhibited a time-dependent and dose-dependent anti-proliferative activity against these cell lines by arresting the cell cycle at the G₀/G₁ phase at physiologically achievable concentrations found in human plasma. The greatest growth inhibition was observed in MDA-MB-468 where the sub-G₀/G₁ apoptotic population was significantly increased, with demonstrable cleavage of PARP. Lycopene induced strong and sustained activation of the ERK1/2, with concomitant cyclin D1 suppression and p21 upregulation in these three cell lines. In triple negative cells, lycopene inhibited the phosphorylation of Akt and its downstream molecule mTOR, followed by subsequent upregulation of proapoptotic Bax without affecting anti-apoptotic Bcl-xL. Taken together, these data indicate that the predominant anticancer activity of lycopene in MDA-MB-468 cells suggests a potential role of lycopene for the prevention of triple negative breast cancer.

Low prostate concentration of lycopene is associated with development of prostate cancer in patients with high-grade prostatic intraepithelial neoplasia

Prostate cancer (PC) is a frequent male malignancy and represents the second most diagnosed cancer in men. Since pre-cancerous lesions, i.e., the high-grade prostatic intraepithelial neoplasia (HGPIN), can be detected years before progression to PC, early diagnosis and chemoprevention are targeted strategies to reduce PC rates. Animal studies have shown that lycopene, a carotenoid contained in tomatoes, is a promising candidate for the chemoprevention of PC. However, its efficacy in humans remains controversial. The present study aimed to investigate the relevance of plasma and prostate concentration of lycopene after a lycopene-enriched diet in patients diagnosed with HGPIN. Thirty-two patients diagnosed with HGPIN were administered a lycopene-enriched diet (20–25 mg/day of lycopene; through 30 g/day of triple concentrated tomato paste) for 6 months. A 6-month follow-up prostate biopsy assessed progression to PC. Patients were classified into three groups according to the histopathological features of the 6-month follow-up biopsy results: prostatitis; HGPIN and PC. PSA and plasma lycopene levels were measured before and after the dietary lycopene supplementation. Prostatic lycopene concentration was only assessed after the supplementation diet. Only prostatic lycopene concentration showed significant differences between the three groups (p = 0.03). Prostatic lycopene concentration below a 1 ng/mg threshold was associated with PC at 6-month follow-up biopsy (p = 0.003). We observed no overall benefits from a 6-month lycopene supplementation, as the rate of HGPIN progression to PC in our population (9/32, 28%) was similar to rates reported in the literature. Baseline PSA levels also showed no significant changes after a lycopene-enriched diet. Our findings point to prostatic lycopene concentration as a promising biomarker of PC. Further prospective longitudinal studies are needed to assess the prognostic role of prostatic lycopene in PC.

Differential bioavailability, clearance, and tissue distribution of the acyclic tomato carotenoids lycopene and phytoene in mongolian gerbils

Lycopene (LYC) is the major tomato carotenoid and is the focus of substantial research. Phytoene (PE), a minor tomato carotenoid, is found in human blood and tissues in similar concentrations to LYC. To determine which metabolic differences underlie this phenomenon, Mongolian gerbils (Meriones unguiculatus, n = 56) were fed control or tomato powder (TP)-containing diets (to establish steady-state serum and tissue carotenoid concentrations similar to tomato-fed humans) for 26 d. The TP-fed gerbils were then provided either a single, oral, cottonseed oil (CO) vehicle dose and tissues were collected at 6 h or they were provided unlabeled PE or LYC in CO and tissues were evaluated at 6, 12, or 24 h. In vehicle-dosed, TP-fed gerbils, LYC was the major carotenoid (≥ 55% carotenoids) in liver, spleen, testes, and the prostate-seminal vesicle complex, whereas PE was the major serum and adipose carotenoid (≥ 37% total carotenoid) and phytofluene was the major carotenoid (≥ 38%) in adrenals and lungs. PE dosing increased hepatic, splenic, and serum PE concentrations compared with vehicle dosing (P < 0.05) from 6 to 24 h, whereas LYC dosing increased only serum LYC at 6 and 12 h (P < 0.05) compared with vehicle dosing. This suggested PE was more bioavailable and cleared more slowly than LYC. To precisely track absorptive and distributive differences, (14)C-PE or (14)C-LYC (n = 2/group) was provided to TP-fed gerbils. Bioavailability assessed by carcass (14)C-content was 23% for PE and 8% for LYC. Nearly every extra-hepatic tissue accumulated greater dose radioactivity after (14)C-PE than (14)C-LYC dosing. Thus, LYC and PE, which structurally differ only by saturation, pharmacokinetically differ in bioavailability, tissue deposition, and clearance.

Potential role of gastrointestinal microbiota composition in prostate cancer risk

Background

Among men in the U.S., prostate cancer is the most common cancer and the second leading cause of cancer death. Despite its prevalence, there are few established risk factors for prostate cancer. Some studies have found that intake of certain foods/nutrients may be associated with prostate cancer risk, but few have accounted for how intake and metabolic factors may interact to influence bioavailable nutrient levels and subsequent disease risk.

Presentation of the hypothesis

The composition of the gastrointestinal (GI) microbiome may influence metabolism of dietary compounds and nutrients (e.g., plant phenols, calcium, choline) that may be relevant to prostate cancer risk. We, therefore, propose the hypothesis that GI microbiota may have a markedly different composition among individuals with higher prostate cancer risk. These individuals could have microbial profiles that are conducive to intestinal inflammation and/or are less favorable for the metabolism and uptake of chemopreventive agents.

Testing the hypothesis

Because very little preliminary data exist on this potential association, a case–control study may provide valuable information on this topic. Such a study could evaluate whether the GI microbial profile is markedly different between three groups of individuals: healthy men, those with latent prostate cancer, and those with invasive prostate cancer. Any findings could then be validated in a larger study, designed to collect a series of specimens over time.

Implications of the hypothesis

Given the plethora of information emerging from the Human Microbiome Project, this is an opportune time to explore associations between the microbiome and complex human diseases. Identification of profiles that alter the host’s risk for disease may clarify inconsistencies in the literature on dietary factors and cancer risk, and could provide valuable targets for novel cancer prevention strategies.

Complex interactions between dietary and genetic factors impact lycopene metabolism and distribution

Intake of lycopene, a red, tetraterpene carotenoid found in tomatoes is epidemiologically associated with a decreased risk of chronic disease processes, and lycopene has demonstrated bioactivity in numerous in vitro and animal models. However, our understanding of absorption, tissue distribution, and biological impact in humans remains very limited. Lycopene absorption is strongly impacted by dietary composition, especially the amount of fat. Concentrations of circulating lycopene in lipoproteins may be further influenced by a number of variations in genes related to lipid absorption and metabolism. Lycopene is not uniformly distributed among tissues, with adipose, liver, and blood being the major body pools, while the testes, adrenals, and liver have the greatest concentrations compared to other organs. Tissue concentrations of lycopene are likely dictated by expression of and genetic variation in lipoprotein receptors, cholesterol transporters, and carotenoid metabolizing enzymes, thus impacting lycopene accumulation at target sites of action. The novel application of genetic evaluation in concert with lycopene tracers will allow determination of which genes and polymorphisms define individual lycopene metabolic phenotypes, response to dietary variables, and ultimately determine biological and clinical outcomes. A better understanding of the relationship between diet, genetics, and lycopene distribution will provide necessary information to interpret epidemiological findings more accurately and to design effective, personalized clinical nutritional interventions addressing hypotheses regarding health outcomes.

Utilization of prostate cancer screening according to dietary patterns and other demographic variables. The adventist health study-2

Background: Prostate-specific antigen test and digital rectal examination are considered important screening methods for early detection of prostate cancer. However, the utilization of prostate cancer screening varies widely and there is limited knowledge of the predictors of utilization.

Methods: Self-reported prostate cancer screening utilization within the last 2 years was investigated among 11,162 black and non-black North American Seventh-day Adventist men, aged 50-75 years, with different dietary patterns and lifestyle characteristics.

Results: Blacks were more likely to screen for prostate cancer than non-blacks (Odds Ratio (OR)=1.38 (95% confidence interval (CI): 1.20-1.57).

Those with a vegetarian diet, especially vegans, were less likely to follow screening guidelines, particularly among non-Blacks: vegans (OR=0.47, 0.39-0.58), lacto-ovo-vegetarians (OR=0.75, 0.66-0.86), and pesco-vegetarians (OR=0.74, 0.60-0.91) compared to non-vegetarians after adjusting for age, BMI, marital status, education, income, and family history of cancer. Trends for dietary patterns remained unchanged after stratification on age, family history of cancer, education, personal income, marital status, and BMI.

Among black men, diet patterns showed no significant associations with utilization of prostate cancer screening, although vegans tended to underutilize screening compared to non-vegetarians (OR=0.70, 0.44-1.10).

Conclusions: Vegetarians, especially non-black vegans, are less likely to follow recommended prostate cancer screening guidelines. The effect of diet was attenuated, and not statistically significant, among black men.

Impact: Since only about 60% of US men follow prostate cancer screening guidelines, it is important to study reasons for non-compliance in order to increase utilization of preventive measures against prostate cancer.

Mediterranean Diet Score and prostate cancer risk in a Swedish population-based case-control study

Several individual components of the Mediterranean diet have been shown to offer protection against prostate cancer. The present study is the first to investigate the association between adherence to the Mediterranean diet and the relative risk of prostate cancer. We also explored the usefulness of the Mediterranean Diet Score (MDS) in a non-Mediterranean population. FFQ data were obtained from 1482 incident prostate cancer patients and 1108 population-based controls in the Cancer of the Prostate in Sweden (CAPS) study. We defined five MDS variants with different components or using either study-specific intakes or intakes in a Greek reference population as cut-off values between low and high intake of each component. Unconditional logistic regression was used to estimate the relative risk of prostate cancer for high and medium v. low MDS, as well as potential associations with the individual score components. No statistically significant association was found between adherence to the Mediterranean diet based on any of the MDS variants and prostate cancer risk (OR range: 0·96-1·19 for total prostate cancer, comparing high with low adherence). Overall, we found little support for an association between the Mediterranean diet and prostate cancer in this Northern European study population. Despite potential limitations inherent in the study or in the build-up of a dietary score, we suggest that the original MDS with study-specific median intakes as cut-off values between low and high intake is useful in assessing the adherence to the Mediterranean diet in non-Mediterranean populations.

Prostate cancer: is it time to expand the research focus to early-life exposures?

Although the contribution of lifestyle and environment (non-genetic factors) to prostate carcinogenesis is indicated by international variation in prostate cancer occurrence and migration studies, no conclusive modifiable risk factors have yet been identified. One possible reason for this may be the dearth of epidemiological research on exposures experienced early in life, when the immature prostate may be more susceptible to carcinogenic exposures. In this Opinion article, we summarize the rationale for studying early-life exposures, describe the small body of early-life research and its associated challenges, and point to solutions for future research.

Lycopene-derived bioactive retinoic acid receptors/retinoid-X receptors-activating metabolites may be relevant for lycopene's anti-cancer potential

Dietary consumption of tomato products and especially the red tomato pigment lycopene has been associated with lower risk of cancer. New evidence is emerging toward metabolic pathways mediating the anti-cancer activities of lycopene. In this review, we explore associations between tomatoes and lycopene intake and cancer and relate this to the metabolic activation pathways of lycopene via carotene oxygenases and further carotenoid/retinoid-metabolizing enzymes to apo-lycopenoids. Several of these apo-lycopenoids have already been identified but up to date no direct connection between lycopene metabolism and apo-lycopenoids mediated receptor activation pathways has been established. Retinoic acid receptors/retinoid-X receptors activation pathways in particular, may be mediated via lycopene metabolites that are related to retinoic acids. Various studies have shown an association between lower concentration of insulin-like growth factor-1 upon lycopene treatment, cancer incidences, and retinoid-mediated signaling. In this review, we interrelate tomato/lycopene ingestion and cancer incidence, with metabolic activation of lycopene and retinoid-mediated signaling. The aim is to discuss a potential mechanism to explain lycopene related anti-cancer activities by modulation of insulin-like growth factor-1 concentrations via lycopene metabolite activation of retinoid-mediated signaling.