Dietary Polyphenol Intake and Gastric Cancer: A Systematic Review and Meta-Analysis

Plant polyphenols in gastric cancer: Nature's healing touch

Globally, gastric cancer ranks as the fifth most common cancer and is the third most common cause of malignancy-associated mortality. Although surgery is the primary treatment option for gastric cancer, adjuvant chemotherapy improves survival in patients following surgery. Proverbially, plant polyphenols have many beneficial health effects, including anticancer properties. Extensive studies have shown that plant polyphenols exhibit potential anticancer effects against gastric cancer in vitro and in vivo, as well as very few human studies. However, this topic has not yet been reviewed. The present review shows that the potential anticancer effect of plant polyphenols on gastric cancer was preliminarily attributed to their antiproliferative, antimetastatic, and antiangiogenic effects and modulations of apoptosis, autophagy, and intracellular reactive oxygen species. Moreover, conventional therapeutics combined with plant polyphenols make gastric cancer cells more sensitive to conventional therapy. We also discuss challenges and opportunities in translating plant polyphenol-based therapy to clinical applications. The content provided in this review is of interest to pharmacologists, ethnobotanists, and oncologists who are involved in phytomedicine.

Effects of Fermented Kimchi Consumption on Anthropometric and Blood Cardiometabolic Indicators: A Systematic Review and Meta-Analysis of Intervention Studies and Prospective Cohort Studies

CONTEXT

Increasing global kimchi consumption has prompted interest in its health impact. However, comprehensive reviews of the influence of kimchi on cardiometabolic risk factors, especially meta-analyses, remain limited.

OBJECTIVE

This review assessed the impact of fermented kimchi consumption on cardiometabolic risk factors by systematically reviewing human intervention and prospective cohort studies, and conducting a meta-analysis of intervention studies.

DATA SOURCES

A literature search of PubMed, EMBASE, Scopus, Web of Science, RISS, KISS, and ScienceON databases was conducted through April 30, 2024. The inclusion criteria encompassed studies that examined the effects of fermented kimchi, without any added ingredients or lactic acid bacteria, on health outcomes, including anthropometric measures, blood pressure, cardiometabolic and glycemic indicators, inflammatory cytokines, and the incidence of related chronic diseases.

DATA EXTRACTION

Data extraction and quality evaluation were conducted independently by 3 researchers.

DATA ANALYSIS

Pooled effect sizes were calculated as weighted mean differences (WMDs) with 95% CIs employing random-effects models.

RESULTS

Five intervention studies (205 participants) and 4 prospective cohort studies (42 455 participants) were selected. A meta-analysis of the intervention studies revealed a significant reduction in fasting blood glucose (WMD: -1.93 mg/dL; 95% CI: -3.82, -0.03; I2 = 17.4%) following the consumption of fermented kimchi. After excluding studies that contributed to increased heterogeneity, significant inverse associations were observed between fermented kimchi consumption and triglycerides (WMD: -28.9 mg/dL; 95% CI: -53.2, -4.5; I2 = 0.0%), systolic blood pressure (WMD: -3.48 mmHg; 95% CI: -5.95, -1.01, I2 = 0.0%), and diastolic blood pressure (WMD: -2.68 mmHg; 95% CI: -4.75, -0.62; I2 = 0.0%). Prospective cohort studies linked higher kimchi intake with a lower incidence of cancer and metabolic syndrome and an increased likelihood of achieving normal body weight.

CONCLUSION

This review supports beneficial effects of fermented kimchi on cardiometabolic health. However, due to the limited number of studies, these findings should be interpreted cautiously, highlighting the need for further research in diverse populations.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration No. CRD42024532020.

The Association Between Anti-Neoplastic Effects of Curcumin and Urogenital Cancers: A Systematic Review

Background: Curcumin is a polyphenol compound with anticancer effects. We aimed to review the anti-neoplastic effects of curcumin on urogenital cancers, by regulating different microRNA expressions. Methods: A systematic search was conducted in Medline (PubMed), Embase, Scopus, and Web of Science up to the end of August 2024. All English, in vitro, and observational studies that evaluated the effect of curcumin on preventing or treating urogenital cancers through its impact on microRNA expression were included. In vivo or silico studies were excluded. Result: A total of 2549 records were found. Finally, 25 studies were included. Twelve studies assessed the effect of curcumin on prostate cancer, six studies on ovarian cancer, three studies on cervical cancer, three studies on bladder cancer, and one study on renal cancer. MicroRNAs are small noncoding RNAs that regulate the post-transcriptional pathways. They possess pivotal roles in different fundamental mechanisms in cells such as differentiation, migration, apoptosis, and proliferation. Curcumin exerts its anticancer effects on urogenital neoplasms by upregulating tumor suppressor microRNAs (miR-143, miR-145, miR-Let-7, miR-101, miR-3127, miR-3178, miR-1275, miR-3198, miR-1908, miR-770, miR-1247, miR-411, miR-34a, miR-383, miR-708, miR-483, miR-199a, miR-335, miR-503, miR-10b, miR-551a, miR-9, miR-203, miR-7110, miR-29b, and miR-126) and downregulating oncogenic microRNAs (miR-21, miR-210, miR-382, miR-654, miR-494, miR-193b, miR-671, miR-222, miR-23b, miR-664, miR-183, miR-214, miR-320a, miR-23a, miR-30a, miR-320d, miR-1285, miR-32, miR-181a, miR-205, miR-216a, miR-1246, and miR-106b). Conclusion: Cell proliferation is inhibited, and cell apoptosis is induced by curcumin in different urogenital cancers through suppressing oncogenic microRNAs or provoking tumor suppressor microRNAs.

Opinion Piece: New Plant-Based Food Products Between Technology and Physiology

The rapid growth of product sectors for plant-based meat and dairy alternatives has raised significant scientific interest in their nutritional and ecological benefits. Here, it outlines the fractionation of plant-based raw materials and describes the technologies applied in the production of meat and dairy substitutes. Moreover, the study describes the effects of these new products on human nutrient supply and metabolic responses. Examples of meat-like products produced by extrusion technology and dairy alternatives are provided, addressing production challenges and the effects of processing on nutrient digestibility and bioavailability. In contrast to animal-based products, plant-based protein ingredients can contain many compounds produced by plants for defense or symbiotic interactions, such as lectins, phytates, and a wide range of secondary metabolites. The intake of these compounds as part of a plant-based diet can influence the digestion, bioaccessibility, and bioavailability of essential nutrients such as minerals and trace elements but also of amino acids. This is a critical factor, especially in regions with limited plant species for human consumption and inadequate technologies to eliminate these compounds. To fully understand these impacts and ensure that plant-based diets meet human nutritional needs, well-controlled human studies are needed.

Sexual dimorphism in the context of nutrition and health

Diets and dietary constituents that we consume have a considerable impact on disease risk. Intriguingly these effects may be modulated to some extent by sex. Lack of female representation in nutritional studies as well as a lack of stratification by sex has and continues to limit our understanding of these sex × diet interactions. Here we provide an overview of the current and available literature describing how exposure to certain dietary patterns (Western-style diet, Mediterranean diet, vegetarian/vegan, ketogenic diet) and dietary constituents (dietary fibre, PUFA and plant bioactive) influences disease risk in a sex-specific manner. Interestingly, these sex differences appear to be highly disease-specific. The identification of such sex differences in response to diet stresses the importance of sex stratification in nutritional research.

Polyphenol intake and gastric cancer: A case-control study in the Brazilian Amazon region

BACKGROUND

Polyphenol intake has been associated with a decreased risk of some types of cancer, including gastric cancer (GC). However, few studies address this topic in the Latin American population. In the present study, we evaluated the association between polyphenol intake and the risk of GC in the Brazilian Amazon region.

METHODS

A case-control study was conducted in Belém (Amazon region) from July 2017 to February 2021. A total of 193 GC cases and 194 controls of both sexes, between 18 and 75 years old, were included in the study. Dietary data were collected using a validated food-frequency questionnaire and polyphenol intake identified using the Phenol-Explorer database. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI), with adjustement for potential confounders.

RESULTS

Cases and controls had similar total polyphenol intake (356.4 mg/1000 kcal/d and 331.1 mg/1000 kcal/d, respectively; p = 0.086). After adjusting for potential confounders, high consumption of flavan-3-ols (highest vs. lowest tertile: OR 0.41, 95% CI 0.18-0.94) and hydroxybenzoic acids (highest vs. lowest tertile: OR 0.24, 95% CI 0.10-0.56) was associated with a decreased risk of GC. The opposite was true regarding the intake of flavones (OR 2.46, 95% IC 1.17-5.18) and other polyphenols (OR 2.54, 95% IC 1.16-5.54). When stratifying according to anatomical topography, we observed that the intake of total flavonoids, flavan-3-ols, and flavanones reduced the risk of cardia GC while that of hydroxybenzoic acids reduced the risk of non-cardia GC. In addition, the intake of flavones and other polyphenols was associated with an increased risk of non-cardia GC. According to histologic subtypes, hydroxybenzoic acid intake was associated with a reduced risk of intestinal-type GC (OR 0.21, 95% IC 0.07-0.64), while flavone consumption was associated with an increased risk of diffuse-type GC (OR 2.59, 95% IC 1.05-6.42).

CONCLUSIONS

Our findings suggest that in the Brazilian Amazon region the high intake of flavan-3-ols and hydroxybenzoic acids is associated with a reduced risk of GC, suggesting a potential beneficial role of these compounds against GC.

Paradigm Shift in Gastric Cancer Prevention: Harnessing the Potential of Aristolochia olivieri Extract

Gastric cancer, particularly adenocarcinoma, is a significant global health concern. Environmental risk factors, such as Helicobacter pylori infection and diet, play a role in its development. This study aimed to characterize the chemical composition and evaluate the in vitro antibacterial and antitumor activities of an Aristolochia olivieri Colleg. ex Boiss. Leaves' methanolic extract (AOME). Additionally, morphological changes in gastric cancer cell lines were analyzed. AOME was analyzed using HPLC-MS/MS, and its antibacterial activity against H. pylori was assessed using the broth microdilution method. MIC and MBC values were determined, and positive and negative controls were included in the evaluation. Anticancer effects were assessed through in vitro experiments using AGS, KATO-III, and SNU-1 cancer cell lines. The morphological changes were examined through SEM and TEM analyses. AOME contained several compounds, including caffeic acid, rutin, and hyperoside. The extract displayed significant antimicrobial effects against H. pylori, with consistent MIC and MBC values of 3.70 ± 0.09 mg/mL. AOME reduced cell viability in all gastric cancer cells in a dose- and time-dependent manner. Morphological analyses revealed significant ultrastructural changes in all tumor cell lines, suggesting the occurrence of cellular apoptosis. This study demonstrated that AOME possesses antimicrobial activity against H. pylori and potent antineoplastic properties in gastric cancer cell lines. AOME holds promise as a natural resource for innovative nutraceutical approaches in gastric cancer management. Further research and in vivo studies are warranted to validate its potential clinical applications.

Factors Associated with Dietary Habit Changes in Korean Stomach Cancer Survivors after Cancer Treatment

The current nutritional guidelines for stomach cancer survivors (SCSs) mainly focus on the influence of the surgical resection of the stomach, with limited guidance regarding a wider range of food options. We aimed to investigate the factors associated with healthier dietary changes in Korean adult SCSs. This cross-sectional study assessed dietary pattern changes after cancer treatment for 11 food categories, using a self-administered questionnaire. A 'healthier dietary change' was operationally defined as a reduced consumption of red and processed meat, grains, salt, and burnt food, and an increased consumption of poultry, fish, vegetables, fruits, legumes, and dairy products. Among a total of 624 SCSs, approximately 60% of participants reported dietary changes in a healthier direction in three or more food categories, while 9.1% reported no changes. There was no significant difference in dietary habit changes between surgery types. Multivariable adjusted analysis showed that elderly and long-term survivors were inversely associated with a healthier dietary change. SCSs with a higher level of educational achievement and income were more likely to make healthier changes in their intake of processed meat, vegetables, fruits, burnt food, or salt. SCSs with higher levels of fear of cancer recurrence, anxiety, or depression were more likely to follow healthier dietary changes regarding fish, meat, fruits, grains, or burnt food. Change in dietary pattern varied across different food items, and was associated with various characteristics of SCSs. It is crucial to repeatedly provide SCSs with information about healthier dietary patterns, considering their sociodemographic, clinical, and psychological characteristics.

Potential Role of Natural Antioxidant Products in Oncological Diseases

Nutrition has a significant effect and a crucial role in disease prevention. Low consumption of fruit and vegetables and a sedentary lifestyle are closely related with the onset and development of many types of cancer. Recently, nutraceuticals have gained much attention in cancer research due to their pleiotropic effects and relatively non-toxic behavior. In fact, although in the past there have been conflicting results on the role of some antioxidant compounds as allies against cancer, numerous recent clinical studies highlight the efficacy of dietary phytochemicals in the prevention and treatment of cancer. However, further investigation is necessary to gain a deeper understanding of the potential anticancer capacities of dietary phytochemicals as well as the mechanisms of their action. Therefore, this review examined the current literature on the key properties of the bioactive components present in the diet, such as carotenoids, polyphenols, and antioxidant compounds, as well as their use in cancer therapy. The review focused on potential chemopreventive properties, evaluating their synergistic effects with anticancer drugs and, consequently, the side effects associated with current cancer treatments.

Adherence to Pro-Vegetarian Food Patterns and Risk of Oesophagus, Stomach, and Pancreas Cancers: A Multi Case-Control Study (The PANESOES Study)

We aimed to evaluate the association between three previously defined pro-vegetarian (PVG) food patterns and the cancers of the oesophagus, stomach, and pancreas in a multi case-control study. We analyzed data from a multi-case hospital-based study carried out in two Mediterranean provinces in Spain. A total of 1233 participants were included in the analyses: 778 incident cancer cases, histologically confirmed (199 oesophagus, 414 stomach, and 165 pancreas) and 455 controls. A dietary assessment was performed using a validated food frequency questionnaire (FFQ). Three PVG food patterns (general, healthful, and unhealthful) were estimated using 12 food groups for the general PVG (gPVG), scoring positive plant-based foods and negative animal-based foods, and 18 food groups, for the healthful (hPVG) and unhealthful (uPVG) food patterns. Multinomial logistic regression was used to estimate relative risk ratios (RRR) and confidence intervals (95% CI) for quintiles of adherence to PVG patterns and as a continuous variable. The RRR (95% CI) for the highest vs. the lowest quintile of gPVG were, RRR = 0.37 (0.32, 0.42) for the oesophagus, RRR = 0.34 (0.27, 0.43) for the stomach, and RRR = 0.43 (0.35, 0.52) for pancreas cancer. For the hPVG, the RRR were RRR = 0.72 (0.58, 0.90) for the oesophagus, RRR = 0.42 (0.34, 0.52) for the stomach, and RRR = 0.74 (0.59, 0.92) for pancreas cancer. The uPVG was associated with a higher risk of stomach cancer RRR = 1.76 (1.42, 2.18). Higher adherence to gPVG and hPVG food patterns is associated with a lower risk of oesophageal, stomach, and pancreas cancers, while a higher adherence to a uPVG food pattern is associated with a higher risk of stomach cancer.