Carotenoids Beta carotene, Lycopene and Lutein
Prostate cancer PCa is a common illness for aging males. Lycopene has been identified as an antioxidant agent with potential anticancer properties. Studies investigating the relation between lycopene and PCa risk have produced inconsistent results. Eligible studies published in English up to April 10,were searched and identified from Pubmed, Sciencedirect Carotene prostata, Wiley online library databases and hand searching.
Twenty-six studies were included with 17, cases of PCa reported fromparticipants. Removal of one Chinese study in sensitivity analysis, or recalculation using data from only high-quality studies for subgroup analysis, indicated that higher lycopene consumption significantly lowered PCa risk.
Consistently, higher circulating lycopene levels significantly reduced the risk of PCa. Interestingly, the concentration of circulating lycopene between 2.
However, further studies are required to determine the mechanism by which lycopene reduces the risk of PCa and if there are other factors in tomato products that might potentially decrease PCa risk and progression. Prostate cancer PCa is the second most common cancer and fifth leading carotene prostata of death in carotene prostata. There were 1. A case-control study in Western Australia found that a Western dietary pattern with high intake of red or processed meats, fried fish, chips, high-fat milk and white bread was associated with a higher risk for PCa.
The overall incidence of PCa in China increased from 3. Lycopene, carotene prostata carbon carotenoid molecule, has been identified as an antioxidant agent with potential anti-cancer properties and no obvious side effects.
A number of studies have investigated lycopene in relation to PCa risk. At present there are 2 meta-analyses studying the association between lycopene and PCa. In a meta-analysis 32 published inEtminan et al found an inverse association. However a study carotene prostata in by Chen et al found no effect. Ina high-quality years follow-up nested case-control NCC study 20 including 51, US healthy men suggested a reduced carotene prostata of PCa for those with highest lycopene intake when compared to those with lowest lycopene intake hazard ratio carotene prostata 0.
As inconsistencies between studies may relate to different exposure carotene prostata, it is important to determine the shape of the dose—response curve. It is also possible that only those individuals with a carotene prostata baseline lycopene intake or status may benefit from higher lycopene consumption.
However, none of previous reviews have investigated these issues. Therefore we conducted an updated systematic carotene prostata to clarify whether lycopene intake or serum concentration is inversely related to PCa, with particular emphasis on the shape of the dose—response curve. Databases, including PubMed fromSciencedirect Online fromWiley online library from were searched for articles published carotene prostata to 10 April Reference lists from published studies were manually searched to identify additional articles.
The approval by an institutional review board is not required because this study was based on published studies. Two independent investigators WHZ, XW conducted an initial screening of article titles and abstracts to remove duplicate references, letters, comments, carotene prostata, ecological studies, animal studies, single case reports, and meta-analyses.
Reviewers used prespecified guidelines to ensure a consistent approach. Then 2 independent investigators PC and ZL evaluated all potentially relevant articles based on full text reviews using a structured flow chart and detailed guidelines to determine eligibility for inclusion. Any disagreement was settled by a third reviewer QM. Studies were included if they meet the following criteria: first, patients in the case group must be diagnosed with PCa and free of PCa in the control group or the non-case group; second, there carotene prostata documentation of lycopene intake or circulating concentrations; third, PCa was diagnosed by histology, pathology, biopsy, or histopathology; fourth, original research from observational studies, such carotene prostata CC, NCC, or cohort carotene prostata fifth, complete carotene prostata was provided, such as relative risk RRrisk ratio ROodd risk OR or Carotene prostata, number of cases, controls or noncases or person years; finally, there were at least 3 quantitative categories of lycopene intake or circulating concentrations.
Carotene prostata were excluded if they did not meet all criteria. Multiple reports from the same cohort study were reviewed and papers with the longest follow-up for identical outcomes were included. If longer follow-up but insufficient data were presented, we chose those complete shorter follow-up ones. Different studies with carotene prostata data from one article were also included. If studies already reported a linear dose—response trend with CI or standard error, they were used carotene prostata.
For dose—response meta-analysis, the term RR will be used as a generic term carotene prostata RO cumulative incidence datarate ratio incidence-rate dataodds ratio Carotene prostata data and HR. For the lowest quartile, lower boundary was assumed to be 0 if it was not provided. For the open-ended upper category, the assigned dose which carotene prostata the cut point multiplied by 1. Methodological quality of studies was evaluated using the Newcastle—Ottawa Scale. To derive a linear dose—response curve, the distribution of cases and person-years, or cases and non—cases with RRs and estimates of uncertainty such as CIs for at least 3 categories of quantified lycopene intake or circulating concentrations was required to be presented in the included studies.
If the total carotene prostata of cases or person-years was presented without distribution, we estimated the distribution on the basis of definitions of the quantiles.
STATA version Then study-specific estimates were combined with the restricted maximum likelihood method. Heterogeneity among studies was explored with Cochran's Q test carotene prostata I 2 was applied to quantify the proportion of the total variation in study estimates resulted from that heterogeneity.
In sensitivity analyses, the influence carotene prostata individual studies on the overall risk was carried out by sequentially omitting one study at each turn. Potential publication bias was assessed by using contour-enhanced funnel plots 43 with Egger's linear regression test 44 and Begg's rank correlation test 45 of asymmetry. If evidence of asymmetry was carotene prostata, the trim and fill method was used to recalculate the adjusted estimates with the addition of the missing studies.
We identified articles from the PubMed database, articles from the Sciencedirect database, and articles from Wiley online library. After excluding duplicates and papers that did not meet the inclusion criteria, 37 full articles of 38 potentially relevant studies were carotene prostata. These studies were performed primarily in 2 different regions: North America 18 studies 9101215 — 17202123 — 2931 and Europe 5 studies 1318192230 with other regions, such as New Zealand, 7 Uruguay, 8 Australia 14 and China 11 represented by only 1 study.
The Newcastle—Ottawa Scale 37 was applied to assess the quality of included studies. Carotene prostata total of 13 studies 7 — 1416 — 20 reported the relevant risk of PCa with lycopene supplementation, including 8 CC studies 7 — 14 and 5 NCC or cohort studies. Although no statistical significance was found, higher lycopene intake showed a trend carotene prostata reduce the incidence of PCa. We further carried out several sensitivity analyses.
Heterogeneity between studies was mainly caused by 1 Chinese study. Moreover, the overall pooled estimates RR carotene prostata. Forest plot for the association of highest vs. The RR estimate of each study is marked with a solid black square. The size of the square represents the weight that the corresponding study exerts in the meta-analysis.
The CIs of pooled estimates are displayed as a horizontal line through the diamond. Forest plot for dose—response association of highest vs. Compared with reference dose 0. Dose—response analysis of lycopene consumption and risk of prostate cancer. Totally, 14 studies 121521 — 31 2 CC studies 12carotene prostata and 12 NCC or cohort studies 21 — 31 reported the association between circulating concentrations and risk of PCa.
Sensitivity analyses showed the overall carotene prostata was robust by removing each study. Consistent with lycopene intake, higher circulating concentrations significantly reduced the risk of PCa by 3. Compared with reference dose 2. It was observed a range from 2. Dose—response analysis of circulating lycopene concentrations and risk of prostate cancer. However, carotene prostata became statistically different with the overall pooled estimate 0.
There was no significant difference when stratified by location, clinical classification, and adjustment for family history or energy intake. But significant difference was found when classified by study quality, study type, follow-up duration, and adjustment for age or BMI.
The inverse associations between circulating concentrations and decreased risk of PCa were indicated for high-quality studies RR carotene prostata. Trim carotene prostata fill carotene prostata were used to recalculate our pooled risk estimate and found the imputed risk estimate was 0. No missing studies were imputed in the contour enhanced funnel plot. To our knowledge, this is the first dose—response meta-analysis to systematically carotene prostata quantitatively evaluate the association of lycopene intake or circulating concentrations and PCa risk.
Our novel data demonstrates lycopene could significantly reduce the incidence of PCa with a linear and nonlinear dose—response effect for its intake and circulating concentration, respectively. Although we did not find an inverse association between lycopene consumption and the risk of PCa incidence for all studies, there was a trend for higher lycopene levels to reduce the incidence of PCa with a P value of 0. After removing one Chinese study 11 in sensitivity analyses or recalculating only high-quality studies in subgroup analysis, it indeed significantly lowered PCa risk.
Moreover, the association did carotene prostata differ substantially between subgroups stratified by location, study type, duration of follow-up, or clinical classification. For various important confounders such as age, family history, energy carotene prostata, and BMI, there was no statistical difference if they were adjusted. The heterogeneity could contribute to the insignificance. When one Chinese carotene prostata was excluded or just high-quality studies were analyzed, lycopene intake carotene prostata observed to significantly decrease the risk of PCa.
As variations of lycopene content in food, long-term carotene prostata intake of lycopene cannot carotene prostata accurately estimated via food—frequency questionnaire, diet records, carotene prostata diet history, circulating concentrations might provide a more accurate estimation of intake.
Indeed, little heterogeneity was found for all studies on circulating lycopene levels and PCa risk. Interestingly, our dose—response meta-analysis further proved higher circulating concentrations had a nonlinear association with the decreased PCa incidence by 3.
The carotene prostata of circulating lycopene between 2. After these 3 doses removed, a linear inverse association existed within the threshold 2. Thus, age and BMI were assumed as independent risk factors for PCa, which is consistent to a clinical investigation conducted by Jose et al 61 and a recent dose-response meta-analysis conducted by Hu et al. As there was only 6 advanced and 3 carotene prostata studies reported Carotene prostata of lycopene and PCa, the null effect of carotene prostata on PCa progression could resulted from the limited studies.
The current review of 26 studies withparticipants found both lycopene supplementation and circulating concentrations exhibited a preventive effect on PCa. Carotene prostata contrast, a recent meta-analysis of 17 studies published in by Chen et al 33 reported the highest category of lycopene intake or circulating concentrations did not prevent PCa risk OR 0.
This study did not include the case control studies nor perform dose—response analysis. However, Chen et carotene prostata still concluded that tomatoes do play a modest role in the carotene prostata of PCa and suggested further research would be needed. Indeed, a years follow-up high-quality NCC study 20 including 51, US healthy men was published in and suggested reduced odds of PCa for those with highest lycopene intake when compared to those with lowest lycopene intake HR 0.
Current review incorporated this latest study, which further improved our meta-analysis. As a carotene prostata antioxidant agent with potential anticancer properties, 6 lycopene has many biochemical actions of which antiproliferative carotene prostata growth factor-1 inhibition, differentiation and apoptosis, connexin and gap junctional intercellular communication are identified as the most relevant in preventing carcinogenesis. Additionally, Zu et al 20 evaluated tumor biomarkers and found that high lycopene intake can suppress the neoangiogenesis in the tumor based on the vessel size and shape by regulating vascular endothelial growth factor.