Consumption of vegetables may reduce the risk of liver cancer: results from a meta-analysis of case-control and cohort studies

An Overview of Hepatocellular Carcinoma with Emphasis on Dietary Products and Herbal Remedies

The most common principal malignant tumor that accounts for ∼80% of cases of liver cancer across the world is hepatocellular carcinoma (HCC). It is a multifacetedillness that is caused by several risk factors and often progresses in the context of underlying cirrhosis. It is tremendously difficult and essential for the screening of novel therapeutic medications to establish HCC preclinical models that are equivalent to clinical diseases settings, i.e., representing the tumor microenvironment of HCC. In the progress of HCC, numerous molecular cascades have been supposed to play a part. Sorafenib is the only drug permitted by the US Food and Drug Administration for the treatment of HCC. Yet because of the increasing resistance to the drug and its toxicity, clinical treatment methods are not completely adequate. Newer treatment therapy options are essential for the management of HCC in patients. Natural compounds can be afforded by the patients with improved results with less toxicity and fewer side effects, among different methods of liver cancer treatment. The treatment and management of HCC with natural drugs and their phytoconstituents are connected to several paths that can prevent the occurrence and progress of HCC in several ways. The present review summarizes the etiology of HCC, molecular pathways, newer therapeutic approaches, natural dietary products, herbal plants and phytoconstituents for HCC treatment.

Herbal and Natural Dietary Products: Upcoming Therapeutic Approach for Prevention and Treatment of Hepatocellular Carcinoma

The most common tumor linked with elevated death rates is considered the hepatocellular carcinoma (HCC), sometimes called the malignant hepatoma. The initiation and progression of HCC are triggered by multiple factors like long term alcohol consumption, metabolic disorders, fatty liver disease, hepatitis B and C infection, age, and oxidative stress. Sorafenib is the merely US Food and Drug Administration (FDA)-approved drug used to treat HCC. Several treatment methods are available for HCC therapy such as chemotherapy, immunotherapy and adjuvant therapy but they often lead to several side effects. Yet these treatment methods are not entirely adequate due to the increasing resistance to the drug and their toxicity. Many natural products help to prevent and treat HCC. A variety of pathways are associated with the prevention and treatment of HCC with herbal products and their active components. Accumulating research shows that certain natural dietary compounds are possible source of hepatic cancer prevention and treatments, such as black currant, strawberries, plum, grapes, pomegranate, cruciferous crops, tomatoes, French beans, turmeric, garlic, ginger, asparagus, and many more. Such a dietary natural products and their active constituents may prevent the production and advancement of liver cancer in many ways such as guarding against liver carcinogens, improving the effectiveness of chemotherapeutic medications, inhibiting the growth, metastasis of tumor cells, reducing oxidative stress, and chronic inflammation. The present review article represents hepatic carcinoma etiology, role of herbal products, their active constituents, and dietary natural products for the prevention and treatment of HCC along with their possible mechanisms of action.

Estimates of the current and future burden of cancer attributable to low fruit and vegetable consumption in Canada

Low fruit and vegetable consumption is associated with colorectal cancer and may be associated with lung, breast, bladder, pancreatic, ovarian, liver, stomach, esophageal, head and neck cancers. We estimated the current attributable and future avoidable burden of cancer associated with low fruit and vegetable consumption in Canada. Using data on cancer incidence, exposure prevalence and risk effects, we estimated the population attributable risk (PAR) for cancers associated with low fruit and vegetable consumption as well as the future avoidable burden. The prevalence of fruit and vegetable consumption was projected to 2032 and cancer incidence was projected to 2042 to estimate the future potential impact fraction of cancer attributable to low fruit and vegetable consumption. Based on estimates from the Canadian Community Health Survey, the prevalence of low fruit (<4 servings/day) and vegetable (<4 servings/day) consumption in the Canadian population was 80.5% and 86.6%, respectively. The PARs for colorectal cancer associated with low fruit and vegetable consumption were 6.1% (1, 371 cases) and 2.2% (487 cases), respectively. For all incident cancers in 2015, 0.7% and 0.3% were attributable to low fruit and vegetable consumption, respectively. An increase of one serving/week of fruit could prevent 20,710 colorectal cancer cases cumulatively by 2042, and the same increase in vegetable consumption could prevent 10,185 cases. Although more research on the association between fruit and vegetable consumption and cancer risk is needed, our results demonstrate that with reasonable increases in current fruit and vegetable consumption by Canadians, over 30,000 colorectal cancer cases could be prevented by 2042.

Fruit and vegetable consumption and health outcomes: an umbrella review of observational studies

The aim of this study was to provide a comprehensive evaluation of current evidence on fruit and vegetable consumption and health outcomes. A systematic search for quantitative syntheses was performed. Several criteria, including study design, dose-response relationship, heterogeneity and agreement of results over time, and identification of potential confounding factors, were used to assess the level of evidence. The strongest (probable) evidence was found for cardiovascular disease protection; possible evidence for decreased risk of colon cancer, depression and pancreatic diseases was found for fruit intake; and colon and rectal cancer, hip fracture, stroke, depression and pancreatic diseases was found for vegetable intake. Suggestive and rather limited associations with other outcomes have been found. Evidence of potential confounding by sex and geographical localisation has been reported. Despite findings are consistent enough for hypothesising causation (at least for cardiovascular-related outcomes), further studies are needed to clarify the role of potential confounding factors.

The Associations of Fruit and Vegetable Intakes with Burden of Diseases: A Systematic Review of Meta-Analyses

BACKGROUND

Low fruit and vegetable intakes are recognized risk factors for noncommunicable diseases. This systematic review summarizes published meta-analyses of global burden of diseases attributable to low fruit and vegetable intakes, and the best relative risk estimates.

METHODS

A published novel assessment process combining Cochrane Review measures, Assessing the Methodological Quality of Systematic Reviews checklist, and Newcastle-Ottawa Quality Assessment Scale was employed.

RESULTS

Sixty-four reports investigating 98 risk-disease pairs were included in the systematic review. Fifty-six pairs from 39 reports were assessed as statistically significant, involving 29 burden of diseases. Dose responses were identified for 31 negative and two positive associations. High against low intake relative risks were identified for 22 negative and one positive association. The highest identified linear dose response for each 100 g/day increase in fruit intakes was 0.56 (95% CI 0.42 to 0.74) for esophageal cancer, followed by 0.72 (95% CI 0.59 to 0.87) for mouth, pharynx, and larynx cancer; nonlinear dose response for the first 100 g/day of fruit intakes were 0.86 (95% CI 0.84 to 0.88) for stroke, followed by 0.89 (95% CI 0.88 to 0.90) for all-cause mortality. The highest identified linear dose response for each 100 g/day increase in vegetable intakes was 0.88 (95% CI 0.80 to 0.95) for renal cell cancer, followed by 0.89 (95% CI 0.84 to 0.95) for non-Hodgkin lymphoma; nonlinear dose responses for the first 100 g/day of vegetable intake were 0.86 (95% CI 0.84 to 0.89) for coronary heart disease, followed by 0.87 (95% CI 0.84 to 0.90) for all-cause mortality. For nonlinear associations, clear increases in protective associations were observed with the first 200 g/day of intakes, whereas little further increase or even decrease in protective associations were reported beyond 300 g/day intakes. Canned fruit intakes were positively associated with all-cause and cardiovascular disease mortality, and pickled vegetable intakes were positively associated with stomach cancer.

CONCLUSIONS

This systematic review supports existing recommendations for fruit and vegetable intakes. Current comparative risk assessments might significantly underestimate the protective associations of fruit and vegetable intakes.

Systematic Review and Meta-Analysis on the Association between Polymorphisms in Genes of IL-12 Signaling Pathway and Hepatocellular Carcinoma Risk

We performed an updated meta-analysis and systematic review to explore the associations between polymorphisms in genes of IL-12 signaling pathway and hepatocellular carcinoma (HCC) risk. Diverse databases were retrieved to identify entire available studies, and odds ratios (ORs) correspondence with 95% confidence intervals (CIs) were performed to assess their associations. Finally, 6 polymorphisms in five genes of the IL-12 signaling pathway were extracted from 39 case-control studies, 26 publications. We identified that STAT4-rs7574865 polymorphism was significantly associated with an increased risk of HCC in allelic contrast, dominant, homozygote and recessive models. However, we failed to uncover any significant association between other polymorphisms in genes of IL-12 signaling pathway and HCC risk, including IL18-rs1946518 and -rs187238, IFN-γ-rs2430561, IL12A-rs568408, IL12B-rs3212227 and STAT4-rs7574865. When the subgroup analysis was conducted based on Hardy-Weinberg Equilibrium (HWE) status, we identified that IFN-γ-rs2430561 polymorphism was significantly associated with an increased risk of HCC in homozygote and recessive models of these studies whose control groups were conformed to HWE. To sum up, our study suggests that STAT4-rs7574865 is a risk factor for HCC. Further well-designed large sample size studies are warranted to shed new light on these findings.

Comparison of the postoperative effect between epidural anesthesia and continuous wound infiltration on patients with open surgeries: A meta-analysis

PURPOSE

The study aimed to compare the effect of epidural anesthesia (EA) and continuous wound infiltration (CWI) on surgical patients.

METHODS

The literature retrieval was conducted in relevant databases from their inception to June 2018 with the predefined searching strategy and selection criteria. Then, the Cochrane Collaboration's tool was used to assess the quality of included studies. In addition, odds ratio (OR) and standardized mean difference (SMD) with its corresponding 95% confidence interval (CI) were used as a measure of effect size for evaluating outcomes indicators.

RESULTS

Totally, sixteen RCTs were included. The incidence of hypotension in EA group was significantly higher than CWI group (OR = 3.7398; 95% CI: 1.0632 to 13.1555). In addition, EA provided better pain relief than CWI on rest at 72 h (SMD = -0.6037; 95% CI: -1.0767 to -0.1308) after surgery. Additionally, there were no significant differences in pain score on rest and mobilization at 2 h, 12 h, 24 h and 48 h. Moreover, the subgroup analysis showed that pain scores in EA group was significantly reduced at 2 h on rest and 12 h on mobilization than CWI group after liver resection surgery, as well as at 72 h on rest after colorectal surgery.

CONCLUSION

CWI is superior to EA with a lower incidence of complications for use in surgery, and EA may provide better pain control than CWI on pain relief after surgery.

Food as Pharma? The Case of Glucosinolates

BACKGROUND

Glucosinolates (GLSs) are dietary plant secondary metabolites occurring in the order Brassicales with potential health effects, in particular as anti-carcinogenic compounds. GLSs are converted into a variety of breakdown products (BPs) upon plant tissue damage and by the gut microbiota. GLS biological activity is related to BPs rather than to GLSs themselves.

METHODS

we have reviewed the most recent scientific literature on the metabolic fate and the biological effect of GLSs with particular emphasis on the epidemiological evidence for health effect and evidence from clinical trials. An overview of potential molecular mechanisms underlying GLS biological effect is provided. The potential toxic or anti-nutritional effect has also been discussed.

RESULTS

Epidemiological and human in vivo evidence point towards a potential anti-cancer effect for sulforaphane, indole-3-carbinol and 3,3-diindolylmethane. A number of new human clinical trials are on-going and will likely shed further light on GLS protective effect towards cancer as well as other diseases. BPs biological effect is the results of a plurality of molecular mechanisms acting simultaneously which include modulation of xenobiotic metabolism, modulation of inflammation, regulation of apoptosis, cell cycle arrest, angiogenesis and metastasis and regulation of epigenetic events. BPs have been extensively investigated for their protective effect towards cancer but in recent years the interest also includes other diseases.

CONCLUSION

It appears that certain BPs may protect against and may even represent a therapeutic strategy against several forms of cancer. Whether this latter effect can be achieved through diet or supplements should be investigated more thoroughly.

Effect of peritoneal dialysis versus hemodialysis on renal anemia in renal in end-stage disease patients: a meta-analysis

The aim of this meta-analysis was to evaluate the effect of peritoneal dialysis (PD) and hemodialysis (HD) on renal anemia (RA) in renal disease patients by a meta-analysis. Relevant studies published before June 2015 were searched. Pooled odds ratio (OR) with 95% confidence interval (CI) was used to evaluate the effect of HD and PD on RA based on five indexes: hemoglobin, ferritin, transferrin saturation index, serum albumin, and parathyroid hormone. Sensitivity analysis and publication bias assessment were conducted to evaluate the stability and reliability of our results. A total of fourteen eligible studies with 1103 cases underwent HD and 625 cases underwent PD were used for this meta-analysis. There were no significant difference for levels of hemoglobin (SMD = -0.23, 95% CI: -0.74 to 0.28), ferritin (SMD = 0.01, 95% CI: -0.59 to 0.62), parathyroid hormone (SMD = 0.11, 95% CI: -1.53 to 1.75) and transferrin saturation index (SMD = -0.06, 95% CI: -0.67 to 0.56) between HD and PD group. However, the content of serum albumin in HD group was much more than that in PD group (SMD = 1.58, 95% CI: 0.35 to 2.81). Neither of the included studies could reverse the pooled side effect and Egger's test demonstrated no publication bias. Both of the two dialysis strategies have a similar effect on RA in renal disease patients.

Exercise Affects Cardiopulmonary Function in Patients with Chronic Kidney Disease: A Meta-Analysis

This study aimed to comprehensively assess the effects of exercise on cardiopulmonary function indices in patients with chronic kidney disease (CKD). A literature review was performed by searching literatures in PubMed and Embase before June 2016. Studies were selected based on predefined inclusion and exclusion criteria, followed by data extraction and a quality assessment of the included studies using the Cochrane Collaboration's tool. Correlations between exercise and cardiopulmonary function indices [pulse wave velocity, respiratory exchange ratio, and peak oxygen uptake (VO₂ peak)] were then evaluated using mean differences and 95% confidence intervals. All meta-analyses were conducted using R 3.12 software. Finally, five eligible studies involving 179 CKD patients were included. After intervention, a heterogeneity test showed that the VO₂ peak values of the treatment group were greater than those of the control group, whereas no significant differences were found for the other indices. However, a sensitivity analysis showed inconsistent results both before and after intervention. Thus, we concluded that exercise might play an important role in improving the VO₂ peak values in CKD patients. Additional studies are needed to verify this conclusion.

The Effect of Three Different Meditation Exercises on Hypertension: A Network Meta-Analysis

We aimed to use the pairwise and network meta-analysis to estimate the effects of different meditation exercises on the control of systolic blood pressure (SBP) and diastolic blood pressure (DBP). Randomized controlled trials (RCTs) were retrieved from PubMed and Embase up to June 2016, which are published in English and reported on meditation exercise for hypertensive patients. Risks of bias assessment of the included studies were assessed by Cochrane Collaboration Recommendations and network meta-analysis was performed by ADDIS. Mean difference (MD) and its 95% confidence interval (CI) were used as the effect size. A number of 19 RCTs were included in this study. Results of pairwise comparisons indicated that meditation exercise could significantly decrease the SBP and DBP, compared with other interventions (MD = −7.10, 95% CI: −10.82 to −3.39; MD = −4.02, 95% CI: −6.12 to −1.92). With good consistence and convergence, network meta-analysis showed that there were no significant differences between meditation and other interventions on SBP. For DBP, Qigong was significantly lower than “no intervention” (MD = −11.73, 95% CI: −19.85 to −3.69). Qigong may be the optimal exercise way in lowering SBP and DBP of hypertensive patients, but a detailed long-term clinical research should be needed in the future.

Reducing effect of aerobic exercise on blood pressure of essential hypertensive patients: A meta-analysis

BACKGROUND

The comprehensive meta-analysis aimed to explore the reductive effect of aerobic exercise on blood pressure of hypertensive patients.

METHODS

The related researches were selected from PubMed and Embase databases up to June 2016. Based on specific inclusive criteria, the eligible studies were selected, and the heterogeneities in their results were estimated by χ-based Q-test and I statistics. Quantitative meta-analysis was assessed by R 3.12 software, and results were presented by standardized mean difference (SMD) and their 95% confidence intervals (CIs). Outcome indicators were systolic blood pressure (SBP) and diastolic blood pressure (DBP). The publication biases were estimated by Egger test. Besides, the "leave one out" method was used for sensitivity evaluations.

RESULTS

As a result, a total of 13 papers with 802 samples were included. Based on the meta-analysis results, there were no significant differences in SBP and DBP between aerobic and control groups before exercise (SMD = 0.15, 95%CI: -0.16-0.46; SMD = 0.16, 95% CI: -0.23-0.55). However, significant reductions were obviously in aerobic group after aerobics, compared with control (SMD = -0.79, 95% CI: -1.29 to -0.28; SMD = -0.63, 95% CI: -1.14 to -0.12). A significant publication bias was detected in SBP (t = -2.2314, P = 0.04549) but not in DBP (t = -1.4962, P = 0.1604). Additionally, the DBP result would be altered after the exclusion of 2 individual papers.

CONCLUSION

Aerobic exercise may be a potential nonpharmacological treatment for blood pressure improvement in essential hypertensive patients.

Meta-analysis for outcomes of acute kidney injury after cardiac surgery

This study aimed to investigate the outcomes of acute kidney injury (AKI) after cardiac surgery by the meta-analysis.Electronic databases PubMed and Embase were searched for relative studies from December 2008 to June 2015. For eligible studies, the R software was conducted to meta-analyze outcomes of AKI patients (AKI group) and none-AKI patients after cardiac surgery (NO AKI group). The chi-square-based Q test and I statistic were used for heterogeneity analysis. P < 0.1 or I > 50% revealed significant heterogeneity among studies, and then a random effects model was used; otherwise a fixed effect model was performed. Egger's test was performed for publication bias assessment. Subgroup analysis was performed by stratifying AKI definitions and study type.Totally 17 studies with 9656 subjects (2331 in the AKI group and 7325 in the NO AKI group) were enrolled. Significantly higher renal replacement therapy (RRT) (OR=23.67, 95%CI: 12.58-44.55), mortality (OR = 6.27, 95%CI: 3.58-11.00), serum creatinine (SMD = 1.42, 95%CI: 1.01-1.83), and hospital length of stay (LOS) (SMD = 0.45, 95%CI: 0.02-0.88) were shown in the AKI group compared with patients in the NO AKI group. Subgroup analysis showed that results of only 3 subgroups were reversed indicating that the definition of AKI did not affect its outcomes. Publication bias was only found among studies involving mortality and serum creatinine, but the 2 outcomes were not reversed after correction.This meta-analysis confirmed the worse outcomes of AKI in patients after cardiac surgery, including higher RRT rates, mortality, and longer hospital LOS than those of NO AKI patients.

Dietary trace element intake and liver cancer risk: Results from two population-based cohorts in China

Dietary factors have been hypothesized to affect the risk of liver cancer via various mechanisms, but the influence has been not well studied and the evidence is conflicting. We investigated associations of dietary trace element intake, assessed through a validated food frequency questionnaire, with risk of liver cancer in two prospective cohort studies of 132,765 women (1997-2013) and men (2002-2013) in Shanghai, China. The associations were first evaluated in cohort studies and further assessed in a case-control study nested within these cohorts adjusting for hepatitis B virus infection. For cohort analyses, Cox proportional hazard models were used to estimate hazard ratios and 95% confidence intervals. For nested case-control analyses, conditional logistic regression was used to calculate odds ratios and 95% confidence intervals. After a median follow-up time of 15.2 years for the Shanghai Women's Health Study and 9.3 years for the Shanghai Men's Health Study, 192 women and 344 men developed liver cancer. Dietary intake of manganese was inversely associated with liver cancer risk (highest vs. lowest quintile, HR = 0.51, 95% CI: 0.35-0.73; p_trend  = 0.001). Further adjustment for hepatitis B virus infection in the nested case-control study yielded a similar result (highest vs. lowest quintile, OR = 0.38, 95% CI: 0.21-0.69; p_trend  < 0.001). No significant association was found between dietary intake of selenium, iron, zinc, copper and liver cancer risk. The results suggest that higher intake of manganese may be associated with a lower risk of liver cancer in China.

Dietary Natural Products for Prevention and Treatment of Liver Cancer

Liver cancer is the most common malignancy of the digestive system with high death rate. Accumulating evidences suggests that many dietary natural products are potential sources for prevention and treatment of liver cancer, such as grapes, black currant, plum, pomegranate, cruciferous vegetables, French beans, tomatoes, asparagus, garlic, turmeric, ginger, soy, rice bran, and some edible macro-fungi. These dietary natural products and their active components could affect the development and progression of liver cancer in various ways, such as inhibiting tumor cell growth and metastasis, protecting against liver carcinogens, immunomodulating and enhancing effects of chemotherapeutic drugs. This review summarizes the potential prevention and treatment activities of dietary natural products and their major bioactive constituents on liver cancer, and discusses possible mechanisms of action.

Increasing vegetable intakes: rationale and systematic review of published interventions

Purpose

While the health benefits of a high fruit and vegetable consumption are well known and considerable work has attempted to improve intakes, increasing evidence also recognises a distinction between fruit and vegetables, both in their impacts on health and in consumption patterns. Increasing work suggests health benefits from a high consumption specifically of vegetables, yet intakes remain low, and barriers to increasing intakes are prevalent making intervention difficult. A systematic review was undertaken to identify from the published literature all studies reporting an intervention to increase intakes of vegetables as a distinct food group.

Methods

Databases—PubMed, PsychInfo and Medline—were searched over all years of records until April 2015 using pre-specified terms.

Results

Our searches identified 77 studies, detailing 140 interventions, of which 133 (81 %) interventions were conducted in children. Interventions aimed to use or change hedonic factors, such as taste, liking and familiarity (n = 72), use or change environmental factors (n = 39), use or change cognitive factors (n = 19), or a combination of strategies (n = 10). Increased vegetable acceptance, selection and/or consumption were reported to some degree in 116 (83 %) interventions, but the majority of effects seem small and inconsistent.

Conclusions

Greater percent success is currently found from environmental, educational and multi-component interventions, but publication bias is likely, and long-term effects and cost-effectiveness are rarely considered. A focus on long-term benefits and sustained behaviour change is required. Certain population groups are also noticeably absent from the current list of tried interventions.