Diet and risk of glioma: combined analysis of 3 large prospective studies in the UK and USA

The gut microbiome and dietary fibres: implications in obesity, cardiometabolic diseases and cancer

Dietary fibres constitute a heterogeneous class of nutrients that are key in the prevention of various chronic diseases. Most dietary fibres are fermented by the gut microbiome and may, thereby, modulate the gut microbial ecology and metabolism, impacting human health. Dietary fibres may influence the occurrence of specific bacterial taxa, with this effect varying between individuals. The effect of dietary fibres on microbial diversity is a matter of debate. Most intervention studies with dietary fibres in the context of obesity and related metabolic disorders reveal the need for an accurate assessment of the microbiome to better understand the variable response to dietary fibres. Epidemiological studies confirm that a high dietary fibre intake is strongly associated with a reduced occurrence of many types of cancer. However, there is a need to determine the impact of intervention with specific dietary fibres on cancer risk, therapy efficacy and toxicity, as well as in cancer cachexia. In this Review, we summarize the mechanisms by which the gut microbiome can mediate the physiological benefits of dietary fibres in the contexts of obesity, cardiometabolic diseases and cancer, their incidence being clearly linked to low dietary fibre intake.

Exploiting the gut microbiome for brain tumour treatment

Increasing evidence suggests that the gut microbiome plays a key role in a host of pathological conditions, including cancer. Indeed, the bidirectional communication that occurs between the gut and the brain, known as the 'gut-brain axis,' has recently been implicated in brain tumour pathology. Here, we focus on current research that supports a gut microbiome-brain tumour link with emphasis on high-grade gliomas, the most aggressive of all brain tumours, and the impact on the glioma tumour microenvironment. We discuss the potential use of gut-brain axis signals to improve responses to current and future therapeutic approaches. We highlight that the success of novel treatment strategies may rely on patient-specific microbiome profiles, and these should be considered for personalised treatment approaches.

A novel golgi related genes based correlation prognostic index can better predict the prognosis of glioma and responses to immunotherapy

BACKGROUND

The Golgi apparatus (GA) serves as the center of protein and lipid synthesis and modification within cells, playing a crucial role in regulating diverse cellular processes as a signaling hub. Dysregulation of GA function can give rise to a range of pathological conditions, including tumors. Notably, mutations in Golgi-associated genes (GARGs) are frequently observed in various tumors, and these mutations have been implicated in promoting tumor metastasis. However, the precise relationship between GARGs and glioma, a type of brain tumor, remains poorly understood. Therefore, the objective of this investigation was to assess the prognostic significance of GARGs in glioma and evaluate their impact on the immune microenvironment.

METHODS

The expression of GARGs was obtained from the TCGA and CGGA databases, encompassing a total of 1564 glioma samples (598 from TCGA and 966 from CGGA). Subsequently, a risk prediction model was constructed using LASSO regression and Cox analysis, and its efficacy was assessed. Additionally, qRT-PCR was employed to validate the expression of GARGs in relation to glioma prognosis. Furthermore, the association between GARGs and immunity, mutation, and drug resistance was investigated.

RESULTS

A selection of GARGs (SPRY1, CHST6, B4GALNT1, CTSL, ADCY3, GNL1, KIF20A, CHP1, RPS6, CLEC18C) were selected through differential expression analysis and Cox analysis, which were subsequently incorporated into the risk model. This model demonstrated favorable predictive efficiency, as evidenced by the area under the curve (AUC) values of 0.877, 0.943, and 0.900 for 1, 3, and 5-year predictions, respectively. Furthermore, the risk model exhibited a significant association with the tumor immune microenvironment and mutation status, as well as a diminished sensitivity to chemotherapy drugs. qRT-PCR analysis confirmed the up-regulation or down-regulation of the aforementioned genes in glioma.

CONCLUSION

The utilization of GARGs in our constructed model exhibits a high level of accuracy in prognosticating glioma and offers promising avenues for the development of therapeutic interventions targeting glioma.

Latent Association Between Diets and Glioma Risk: A Mendelian Randomization Analysis

BACKGROUND

Gliomas, particularly high-grade gliomas such as glioblastoma, represent a major challenge due to their poor prognosis. While dietary factors have been proposed as potential modulators of glioma risk, causal inference has been hindered by confounding and reverse causality in observational studies. This study employs Mendelian randomization to investigate the causal relationship between dietary factors and glioma risk.

METHODS

A two-sample MR framework was applied, utilizing genome-wide association study data for 22 dietary exposures and glioma risks, including both GBM and non-GBM subtypes. Instrumental variables (genetic variants) were identified for each dietary factor to address confounding and pleiotropy. Causal inference was conducted using inverse-variance weighted regression, complemented by MR-Egger and MR-PRESSO analyses to assess and correct for potential pleiotropy.

RESULTS

A positive causal association was observed between the intake of cooked vegetables and the GBM risk (OR = 6.55, 95% CI: 1.86-23.12, p = 0.00350). While alcohol intake demonstrated a protective effect for non-GBM risk (OR = 0.770, 95% CI: 0.61-0.97, p = 0.029), beer was substantially linked to an increased risk of non-GBM gliomas (OR = 4.82, 95% CI: 1.84-12.59, p = 0.0014). Other dietary factors did not exhibit significant causal associations.

CONCLUSIONS

These findings suggest that certain dietary factors, including cooked vegetable intake, beer consumption, and alcohol intake, may exert a causal influence on glioma risk. This study provides new insights into the potential dietary determinants of glioma and underscores the need for further investigation into modifiable risk factors for glioma prevention.

Coffee and tea consumption and glioma risk: a meta-analysis of cohort studies

Background

Research on the association between glioma risk and coffee and tea consumption remains inconclusive. This study seeks to present a meta-analysis of the relationship between coffee and tea intake and glioma risk.

Method

Relevant cohort studies that collected coffee and tea exposure prospectively were identified through searches of the PubMed, Embase, and Scopus databases. Eligible studies included those providing adjusted relative risk estimates or hazard ratios (HRs) with 95% confidence intervals (CIs), or data sufficient for such calculations. Study quality was evaluated using the Newcastle-Ottawa Scale, while the GRADE system assessed the quality of evidence. The analysis explored glioma risk concerning the highest versus lowest levels of coffee and tea intake, supplemented by a dose-response evaluation using a one-stage robust error meta-regression model.

Results

A total of nine studies, published between 2004 and 2020, were included. In a model comparing the highest and lowest levels of coffee and tea consumption, 3,896 glioma cases were identified among 2,648,468 participants. Correspondingly, the pooled HRs with 95% CIs were 0.98 (0.87-1.09) for coffee and 0.95 (0.86-1.06) for tea, respectively. Furthermore, no evidence of publication bias was detected for either beverage. The dose-response analysis indicated a near "L"-shaped relationship between tea consumption and glioma risk, with the most notable risk reduction observed in individuals consuming more than 2.5 cups of tea per day. However, additional tea intake beyond this threshold did not confer evident risk reduction. According to Grade scoring system, the quality of meta-evidence was classified as "very low" for coffee and "low" for tea.

Conclusion

This meta-analysis provides evidence suggesting a potential inverse association between tea consumption and glioma risk, while no such association was observed for coffee consumption. Given that the evidence for coffee was classified as "very low" and for tea as "low," cautious interpretation of the findings is warranted, and further research is needed to validate these results.

Dietary Recommendations for Glioma: A Mini-Review

PURPOSE OF REVIEW

Glioma is the most common type of brain cancer, associated with a high mortality rate. Diet is one of the most modifiable factors that can influence the risk of various cancers, including glioma. While the relationship between diet and glioma has been explored in recent years, the number of studies in this area remains limited, and the findings are often controversial. Moreover, all existing studies are observational, which means they may be influenced by a range of confounding variables. In this mini-review, we aim to provide a comprehensive and informative overview of the dietary recommendations related to glioma that have been published to date.

RECENT FINDINGS

Research suggests that adherence to healthy dietary patterns-such as the Mediterranean diet, Dietary Approaches to Stop Hypertension (DASH) diet, Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet, Paleolithic diet, high-protein dietary patterns, and vegetarian dietary patterns-may be associated with a reduced risk of glioma. These diets are rich in phytochemicals and antioxidants. Additionally, certain food groups, including fruits, vegetables, legumes, nuts, eggs, fresh fish, tea, and coffee, are emphasized for their protective effects against glioma. Conversely, adherence to unhealthy dietary patterns, such as the Western diet, or diets with high inflammatory potential, glycemic and insulinemic loads, and high consumption of grains (especially refined grains), processed meats, and processed fish, has been linked to an increased risk of glioma. Current studies suggest that following a healthy diet may reduce the odds of developing glioma. However, due to the limited number of studies and the observational nature of the existing research, further investigations with more robust designs, such as randomized controlled trials, are needed to clarify these associations.

Epidemiology of malignant brain tumors in Genova, Italy. 1993-2017

We present an updated analysis on the incidence of primary brain tumors in the Metropolitan Area of Genova, the capital of the northwestern Italian region Liguria.The number of cases and incidence rates for all malignant brain tumors, glioblastoma, malignant brain tumors other than glioblastoma, and brain tumors not otherwise specified were calculated for each of seven three-year and one-eighth four-year periods in which the quarter century 1993-2017 was divided. The rates were age-adjusted (AAR) using the 2013 European standard population, presented per 100,000 person-years and the average percentage change over the three-year period was calculated.The number of cases of all malignant brain tumors and glioblastoma was higher in males than in females in each three-year period and in the entire quarter century 1993-2017. During the latter, the average three-year percentage change in AARs for all brain tumors was minimal [0.6 (95% C.I. = -1.0/2.1) %] while for glioblastoma there was a change of 5.3 (95% C.I. = -0.4/11.3) %. The partially concurrent decline in the incidence rates of malignant brain tumors other than glioblastoma or not otherwise specified suggests that the observed increase in the incidence rate of glioblastoma during 1993-2017 may have been at least partially linked to the improvement during the same period in sensitivity and specificity of the diagnosis of glioblastoma, depleting the reservoirs of other malignant or unspecified brain tumors. Research into possibly increased environmental risk factors (e.g., population exposure to ionizing radiation) for glioblastoma in Genova remains warranted.

Association of multiple trace metals in scalp hair with glioma risk: the mediating role of inflammation

OBJECTIVE

To explore the relationship between 35 trace metals in scalp hair and the glioma risk as well as the potential mediating roles of 27 plasma inflammatory cytokines.

METHODS

A case-control study involving 228 participants was performed in southeastern China. Trace metals in scalp hair were analyzed using inductively coupled plasma mass spectrometry, and multiplex cytokines were detected based on Luminex® technology. The least absolute shrinkage and selection operator (LASSO) regression in combination with four machine learning methods were used to select trace metals associated with gliomas. The joint exposure effect of trace metals was estimated using the generalized weighted quantile sum (gWQS) regression and quantile-based g-computation (qgcomp) algorithms.

RESULTS

Both LASSO regression and random forest algorithms identified five trace metals (gadolinium [Gd], lithium [Li], thulium [Tm], thorium [Th], and molybdenum [Mo]) associated with gliomas. After adjustments for potential confounders, Gd (odds ratio [OR] = 2.84, 95% confidence interval [CI]: 1.89-4.43) and Li (OR = 1.77, 95% CI: 1.04-3.02) concentrations were positively associated with glioma risk, while Tm (OR = 0.36, 95% CI: 0.17-0.73) and Th (OR = 0.45, 95% CI: 0.28-0.71) exhibited inverse associations. Both gWQS and qgcomp algorithms showed Gd contributed most to the mixture effect. Moreover, there was a significant interaction between Gd and Tm or Th on glioma risk (p < 0.05). Notably, granulocyte-macrophage colony-stimulating factor (GM-CSF) mediated the association between Gd exposure and glioma risk by 25.75%.

INTERPRETATION

These findings suggest potential associations of certain trace metals, especially for Gd, with glioma risk, and may provide new insights into the mechanisms underlying from an inflammatory response perspective.

Dietary patterns in relation to glioma: a case-control study

Although the association of individual foods and nutrients with glioma have been investigated, studies on the association of major dietary patterns and glioma are scarce. The aim of this study was to examine the association between major dietary patterns and risk of glioma in a group of Iranian adults. In this hospital-based case-control design, we recruited 128 newly diagnosed glioma cases and 256 controls in Tehran from 2009 to 2011. A Willett-format-validated 126-item semi-quantitative Food Frequency Questionnaire (FFQ) was used to assess participants' dietary intake. Factor analysis was used to identify major dietary patterns. We identified 3 major dietary patterns using factor analysis: high protein, vegetarian and western dietary pattern. After several adjustments for potential confounders, adherence to the high protein dietary pattern was inversely associated with risk of glioma (OR: 0.47; 95% CI: 0.23, 0.95). Consumption of vegetarian dietary pattern was also associated with a reduced risk of glioma (OR: 0.16; 95% CI: 0.07, 0.34). Greater adherence to the western dietary pattern was associated with a greater chance of glioma (OR: 3.30; 95% CI: 1.52, 7.17). We found that high protein, vegetarian and western dietary pattern were significantly associated with glioma risk. Further prospective studies are needed to confirm these findings.

Healthy Lifestyle and Cancer Risk: Modifiable Risk Factors to Prevent Cancer

Cancer has become a serious problem worldwide, as it represents the main cause of death, and its incidence has increased over the years. A potential strategy to counter the growing spread of various forms of cancer is the adoption of prevention strategies, in particular, the use of healthy lifestyles, such as maintaining a healthy weight, following a healthy diet; being physically active; avoiding smoking, alcohol consumption, and sun exposure; and vitamin D supplementation. These modifiable risk factors are associated with this disease, contributing to its development, progression, and severity. This review evaluates the relationship between potentially modifiable risk factors and overall cancer development, specifically breast, colorectal, and prostate cancer, and highlights updated recommendations on cancer prevention. The results of numerous clinical and epidemiological studies clearly show the influence of lifestyles on the development and prevention of cancer. An incorrect diet, composed mainly of saturated fats and processed products, resulting in increased body weight, combined with physical inactivity, alcohol consumption, and smoking, has induced an increase in the incidence of all three types of cancer under study. Given the importance of adopting correct and healthy lifestyles to prevent cancer, global institutions should develop strategies and environments that encourage individuals to adopt healthy and regular behaviors.

Adherence to Healthy Dietary Patterns and Glioma: A Matched Case-Control Study

Recent studies have revealed a putative relationship between diet and glioma development and prognosis, but few studies have examined the association between overall diet and glioma risk. This study, conducted in China, employed a hospital-based case-control approach. The researchers utilized an a priori method based on dietary data to evaluate compliance scores for five healthy dietary patterns (the Mediterranean diet, the Dietary Approaches to Stop Hypertension (DASH) diet, the Mediterranean-DASH diet Intervention for Neurodegenerative Delay (MIND) diet, the Paleolithic diet, and the Planetary Health Diet) in 1012 participants. At the same time, data-driven methods were used to explore the association between dietary patterns and glioma via principal component analysis (PCA). In the multivariate model, adhering to the Mediterranean diet (odds ratio (OR) = 0.29; 95% confidence interval (95% CI): 0.17-0.52), the DASH diet (OR = 0.09; 95% CI: 0.04-0.18), the MIND diet (OR = 0.25; 95% CI: 0.14-0.44), and the Paleolithic diet (OR = 0.13; 95% CI: 0.06-0.25) was associated with a reduced glioma risk. The results of PCA suggested that increasing the intake of plant-based foods and fish and limiting foods rich in carbohydrates, fats, and salts were associated with a reduced glioma risk. There was a substantial nonlinear dose-response association between glioma and the Mediterranean diet score. However, the DASH diet score, the MIND diet score, and the Paleolithic diet score exhibited linear dose-response relationships. Therefore, this study finds that dietary patterns may be an influencing factor for glioma risk.

Chinese Dietary Indices and Glioma: New Insights of a Case-Control Study in the Chinese Population

Identifying modifiable factors in primary prevention strategies is a typical goal of glioma epidemiology. Among many glioma risk factors, diet was always considered as one. Most of the relevant studies thus far were concentrated on the West. It was crucial to investigate the connection between the Chinese diet and gliomas given the stark variations between western and eastern diets. A food frequency questionnaire including 114 items was used to investigate the food intake of the study subjects. The Chinese Dietary Quality Index (CDQI), the Chinese Dietary Balance Index (CDBI), the Dietary Antioxidant Index (DAI), the Dietary Inflammation Index (DII), and the Chinese Healthy Eating Index (CHEI) were calculated based on the data provided by the food frequency questionnaire to evaluate dietary quality, dietary balance, dietary antioxidants, dietary inflammation and adherence to the Chinese dietary guidelines in 506 glioma patients and 506 controls, respectively. After adjusting covariates, CHEI (OR = 0.90, 95% CI: 0.88-0.93) and DAI (OR = 0.61, 95% CI: 0.54-0.70) were correlated to a reduced glioma risk, and CDBI-based undernutrition (OR = 1.08, 95% CI: 1.06-1.12) and overnutrition (OR = 1.14, 95% CI: 1.09-1.20) and DII (OR = 2.20, 95% CI: 1.81-2.68) were correlated to an elevated glioma risk. Moreover, restrictive cubic spline analysis showed that there were significant nonlinear dose-response relationships between CHEI, CDBI, DAI, DII, and glioma. Therefore, adhering to the Chinese dietary guidelines was connected with a lower glioma risk, and undernutrition and overnutrition in the Chinese diet were associated with an increased risk of glioma.

Modifiable risk factors for glioblastoma: a systematic review and meta-analysis

Glioblastoma (GBM) is the most common and aggressive glioma histological subtype, associated with high disability and poor survival. The etiology of this condition is still mostly unknown, and evidence about risk factors is elusive. The aim of this study is to identify modifiable risk factors for GBM. Electronic search was performed by two reviewers independently using the keywords and MeSH terms 'glioblastoma' OR 'glioma' OR 'brain tumor' AND 'risk factor'. The inclusion criteria were (1) observational studies or experimental studies on humans, (2) studies assessing the association between glioblastoma and exposure to modifiable conditions, and (3) studies published in English or Portuguese. Studies on the pediatric population or about exposure to ionizing radiation were excluded. A total of 12 studies were included. Seven were case-control studies, and five were cohort studies. The risk factors assessed included body mass index, alcohol consumption, exposure to magnetic fields, diabetes mellitus type 2 (DM2), and use of non-steroidal anti-inflammatory drugs (NSAID). No significant link was found between GBM incidence and DM2 or magnetic field exposure. On the other hand, higher BMI, alcohol consumption, and NSAID use demonstrated a protective effect on GMB risk. However, given the limited number of studies, it is not possible to obtain a behavioral recommendation; instead, these findings are relevant to guide future basic scientific studies on GBM oncogenesis.

Healthy dietary patterns, foods, and risk of glioma: A systematic review and meta-analysis of observational studies

Background

Accumulating epidemiological evidence has shown the favorable associations between healthy dietary patterns and risk of glioma, although the results remain inconclusive.

Objective

We therefore carried out a systematic review and meta-analysis to summarize the evidence from previous published studies, and to clarify the effects of healthy dietary patterns, typical healthy foods on glioma.

Methods

PubMed, Web of Science, CNKI, and Wan fang data were searched from inception up to September 2022 for eligible studies. Two authors independently performed the literature search, study selection, data extraction, and quality assessment. Heterogeneity across studies was estimated using the Cochran's Q test and I ² statistic. According to heterogeneity, the fixed-effects model or random-effects model was selected to obtain the relative risk (RR) of the merger. Subgroup analysis, sensitivity analysis and publication bias were also used for our analysis.

Results

Twenty-four articles that met the selection criteria, involving 7,278 glioma cases and 2,143,528 participants, were included in our analysis. There was a reduced risk of glioma in the highest compared with the lowest categories of healthy dietary patterns (RR = 0.58; 95% CI: 0.44-0.77; P < 0.0001). Moreover, compared with the lowest intakes, the highest intakes of vegetables (RR = 0.84; 95% CI: 0.73-0.96; P = 0.012) and fruits (RR = 0.85; 95% CI: 0.72-1.00; P = 0.045) significantly reduce the risk of glioma. However, the intakes of fresh fish, nuts, whole grains, and dairy products showed no statistically significant associations with the risk of glioma (P > 0.05).

Conclusion

Findings from this systematic review and meta-analysis indicate that higher intakes of healthy dietary patterns, vegetables, and fruits are significantly associated with the lower risk of glioma. Further studies, particularly with prospective design, are required to confirm our findings.

Signaling pathways in brain tumors and therapeutic interventions

Brain tumors, although rare, contribute to distinct mortality and morbidity at all ages. Although there are few therapeutic options for brain tumors, enhanced biological understanding and unexampled innovations in targeted therapies and immunotherapies have considerably improved patients' prognoses. Nonetheless, the reduced response rates and unavoidable drug resistance of currently available treatment approaches have become a barrier to further improvement in brain tumor (glioma, meningioma, CNS germ cell tumors, and CNS lymphoma) treatment. Previous literature data revealed that several different signaling pathways are dysregulated in brain tumor. Importantly, a better understanding of targeting signaling pathways that influences malignant behavior of brain tumor cells might open the way for the development of novel targeted therapies. Thus, there is an urgent need for a more comprehensive understanding of the pathogenesis of these brain tumors, which might result in greater progress in therapeutic approaches. This paper began with a brief description of the epidemiology, incidence, risk factors, as well as survival of brain tumors. Next, the major signaling pathways underlying these brain tumors' pathogenesis and current progress in therapies, including clinical trials, targeted therapies, immunotherapies, and system therapies, have been systemically reviewed and discussed. Finally, future perspective and challenges of development of novel therapeutic strategies in brain tumor were emphasized.

Ionizing radiation exposure during adulthood and risk of developing central nervous system tumors: systematic review and meta-analysis

Many studies on ionizing radiation (IR) exposure during childhood have shown deleterious effects on the central nervous system (CNS), however results regarding adult exposure are inconsistent, and no systematic reviews have been performed. The objectives are to synthesize the findings and draw evidence-based conclusions from epidemiological studies on the risk of benign and malignant brain and CNS tumors in humans exposed to low-to-moderate doses (< 0.5 Gy) of IR during adulthood/young adulthood. A systematic literature search of four electronic databases, supplemented by a hand search, was performed to retrieve relevant epidemiological studies published from 2000 to 2022. Pooled excess relative risk (ERRpooled) was estimated using a random effect model. Eighteen publications were included in the systematic review and twelve out of them were included in a meta-analysis. The following IR sources were considered: atomic bombs, occupational, and environmental exposures. No significant dose-risk association was found for brain/CNS tumors (ERRpooled at 100 mGy = - 0.01; 95% CI: - 0.05, 0.04). Our systematic review and meta-analysis did not show any association between exposure to low-to-moderate doses of IR and risk of CNS tumors. Further studies with histological information and precise dose assessment are needed.

Oral Contraceptive and Glioma Risk: A Prospective Cohort Study and Meta-Analysis

Background

Epidemiological evidence that glioma has a slight male predominance implies that factors associated with sex hormones may play a role in the development of glioma. The association between oral contraceptive (OC) use and glioma risk remains controversial.

Method

In the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial of 70,516 women in the USA, Cox proportional hazards regression analyses were adopted to calculate the crude and adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). Additionally, a meta-analysis combining the PLCO findings with those of other prospective cohorts was performed.

Results

During a mean follow-up of ~11.7 years, 110 of 70,516 women aged 50–78 years at baseline were diagnosed with glioma in PLCO studies. Compared with never users, an inverse association of borderline significance was found for OC users (HR 0.67, 95% CI 0.44–1.04, P = 0.074). Analyses assessing glioma risk according to the duration of OC use yielded no significant association. When PLCO was combined with four other prospective studies, there was an inverse association between OC use and glioma risk (HR 0.85, 95% CI 0.75–0.97, I² = 0.0%). Further dose-response analysis showed a nonlinear, inverse relationship between OC use and glioma risk (P < 0.001).

Conclusions

This study provided some evidence of a nonlinear, inverse association between OC use and glioma risk. Future larger studies are warranted to validate this finding.

Epidemiology of Glioblastoma Multiforme-Literature Review

Glioblastoma multiforme (GBM) is one of the most aggressive malignancies, with a median overall survival of approximately 15 months. In this review, we analyze the pathogenesis of GBM, as well as epidemiological data, by age, gender, and tumor location. The data indicate that GBM is the higher-grade primary brain tumor and is significantly more common in men. The risk of being diagnosed with glioma increases with age, and median survival remains low, despite medical advances. In addition, it is difficult to determine clearly how GBM is influenced by stimulants, certain medications (e.g., NSAIDs), cell phone use, and exposure to heavy metals.

Pesticide Residue Intake From Fruit and Vegetable Consumption and Risk of Glioma

We aimed to determine whether intake of pesticide residues from fruits and vegetables was associated with glioma. Within 3 prospective cohorts from 1998-2016-the Nurses' Health Study (NHS), Nurses' Health Study II (NHSII), and Health Professionals Follow-up Study-we computed multivariable-adjusted hazard ratios (MVHRs) and 95% confidence intervals (CI) for glioma by quintiles of intake of low- and high-pesticide-residue fruits and vegetables using Cox proportional hazards regression. Fruits and vegetables were categorized as high or low residue using a validated method based on pesticide surveillance data. We confirmed 275 glioma cases across 2,745,862 person-years. A significant association was observed between intake of high-residue fruits and vegetables and glioma in NHS (MVHR = 2.99, 95% CI: 1.38, 6.44 comparing highest with lowest quintile, P for trend = 0.02). This was not identified in NHSII (MVHR = 0.52, 95% CI: 0.19, 1.45, P for trend = 0.20) or Health Professionals Follow-up Study (MVHR = 1.01, 95% CI: 0.42, 2.45, P for trend = 0.39). No significant associations were observed by intake of low-residue fruits and vegetables; overall intake was not significantly associated with glioma in any cohort. We found no evidence for an inverse relationship of fruit and vegetable intake with glioma. Although limited in power, this study suggests a possible association between fruit-and-vegetable pesticide residue intake and risk of glioma that merits further study.

Dietary Factors and Risk of Glioma in Adults: A Systematic Review and Dose-Response Meta-Analysis of Observational Studies

Background

Gliomas are the most common primary intracranial tumors in adults. Inappropriate dietary habits are thought to be a risk factor for most human cancer, and glioma is no exception. However, the effect of dietary factors on glioma is not clear.

Objective

This review aims to quantitatively evaluate the association between various dietary intakes and glioma using a meta-analysis.

Methods

We searched articles on PubMed, the Cochrane Library, the Web of Science, and EMBASE from their inception until October 11, 2021. According to heterogeneity, the fixed-effects or random-effects model was selected to obtain the relative risk (RR) of merger. Based on the methods described by Greenland and Longnecker, we explored the dose-response relationship between dietary intakes and the risk of glioma. Subgroup analysis, sensitivity analysis, and publication bias were also used.

Results

This study reviewed 33 articles, including 3,606,015 controls and 8,831 patients with glioma. This study included 12 food groups. Compared with the lowest intakes, the highest intakes of tea (RR = 0.82, 95%CI:0.71–0.93), total vegetables (RR = 0.84, 95%CI: 0.70–1.00), green vegetables (RR = 0.80, 95%CI: 0.66–0.98), and orange vegetables (RR = 0.79, 95%CI: 0.66–0.96) significantly reduced the risk of glioma, while the highest intakes of grains (RR = 1.39, 95%CI: 1.16–1.66), processed meats (RR = 1.19, 95%CI: 1.00–1.42), and processed fish (RR = 1.37, 95%CI: 1.03–1.84) significantly increased the risk of glioma. The results of subgroup and sensitivity analyses remained unchanged. In the dose-response relationship, only tea was statistically significant. Taking an extra cup of tea every day reduced the risk of glioma by 4%.

Conclusions

Our analysis suggests that the intakes of tea, total vegetables, green vegetables, and orange vegetables may reduce the risk of glioma, while the intakes of grains, processed meats, and processed fish may increase the risk of glioma. Therefore, the effect of dietary factors on glioma should not be ignored.

Systematic Review Registration:https://www.crd.york.ac.uk/prospero/, CRD42022296658.

Alcohol intake and risk of pituitary adenoma

BACKGROUND

The association between alcohol intake and incidence of pituitary adenoma has not been reported previously. We examined this association in three large, prospective cohort studies.

METHODS

Using data from the Nurses' Health Study, Nurses' Health Study II, and Health Professionals Follow-Up Study, we computed multivariable-adjusted hazard ratios (MVHR) and 95% confidence intervals (CI) for pituitary adenoma by levels of alcohol intake using Cox proportional hazards regression.

RESULTS

We identified 292 incident cases of pituitary adenoma (225 among women, 67 among men) among 235,973 participants with 6,548,732 person-years of follow-up. Compared with intake of ≤ 0.5 g/day, cumulative average alcohol intake in all categories was associated with reduced risk of pituitary adenoma (MVHR = 0.60, 95% CI 0.43-0.83 for 0.5-≤ 2 g/day, MVHR = 0.57, 95% CI 0.41-0.79 for > 2.0-≤ 8.0, MVHR = 0.70, 95% CI 0.47-1.04 for > 8.0-≤ 15.0, and MVHR = 0.51, 95% CI 0.32-0.83 for > 15.0 g/day). Significant inverse findings were present in women and were similar but non-significant in men. For specific alcoholic beverages, inverse associations were statistically significant for total wine (MVHR = 0.58, 95% CI 0.43-0.79 comparing 0.5-≤ 2 to ≤ 0.5 g/day), red wine (MVHR = 0.65, 95% CI 0.46-0.92 comparing 0.5-≤ 2 to ≤ 0.5 g/day), and white wine (MVHR = 0.72, 95% CI 0.53-0.97 comparing 0.5-≤ 2 to ≤ 0.5 g/day). Results were consistent using baseline intake, recent intake, and with an 8-year lag.

CONCLUSION

In three prospective cohorts, compared to almost no consumption, alcohol consumption was associated with reduced risk of pituitary adenoma. Sensitivity analyses suggest that these results are unlikely to be the result of reverse causation or diagnostic bias.

The Epidemiology of Central Nervous System Tumors

This article reviews the current epidemiology of central nervous system tumors. Population-level basic epidemiology, nationally and internationally, and current understanding of germline genetic risk are discussed, with a focus on known and well-studied risk factors related to the etiology of central nervous system tumors.

A combined healthy lifestyle score in relation to glioma: a case-control study

Background

The evidence on the association between adherence to a healthy lifestyle and risk of glioma are scarce. This is particularly relevant to Middle Eastern countries where lifestyle factors including dietary intakes, physical activity and environmental contributors are different from other parts of the world. The aim of this case-control study was, therefore, investigating the association between adherence to a healthy lifestyle and odds of glioma among adults.

Methods

Totally, 128 newly diagnosed glioma cases and 256 age- and sex-matched controls were recruited in this hospital-based case-control study. Dietary intakes were examined by the use of a 126-item validated FFQ. International Physical Activity Questionnaire (IPAQ) was used for measuring physical activity of participants. To construct a healthy lifestyle score (HLS), data from dietary intakes, physical activity and BMI were used. Subjects in the low risk categories of the mentioned components received the score of 1, otherwise they received the score of 0. The final HLS was computed through summing up the scores of components.

Results

After adjustment for age and sex, we found that individuals with the highest HLS score were 55% less likely to have glioma compared with those with the lowest score (OR: 0.45; 95% CI: 0.22, 0.92). Additional controlling for other potential confounders made the association stronger (OR: 0.28; 95%CI: 0.12, 0.66). In terms of individual components of healthy lifestyle score, subjects with a healthy diet had 54% lower odds of glioma than those with a non-healthy diet (OR: 0.46; 95%CI: 0.26, 0.80). No significant associations were seen between physical activity level or BMI status and glioma.

Conclusion

We found evidence indicating that adherence to a healthy lifestyle, in particular a healthy diet, was associated with a lower odds of glioma. Prospective cohort studies are needed to confirm these findings.

Trends in Intracranial Glioma Incidence and Mortality in the United States, 1975-2018

Purpose

Glioma incidence in the US seems to have stabilized over the past 20 years. It’s also not clear whether changes in glioblastoma incidence are associated with glioma mortality trends. Our study investigated trends in glioma incidence and mortality according to tumor characteristics.

Methods

This study obtained data from the Surveillance, Epidemiology, and End Results-9 (SEER-9) registries to calculate glioma incidence and mortality trends. Annual percent changes (APC) and 95% CIs were calculated using the Joinpoint program.

Results

62,159 patients (34,996 males and 55,424 whites) were diagnosed with glioma during 1975-2018, and 31,922 deaths occurred from 1995-2018. Glioblastoma (32,893 cases) and non-glioblastoma astrocytoma (17,406 cases) were the most common histologic types. During the study period, the incidence of glioma first experienced a significant increase (APC=1.8%, [95% CI, 1.3% to 2.3%]) from 1975 to 1987, and then experienced a slight decrease (APC=-0.4%, [95% CI, -0.5% to -0.3%]) from 1987 to 2018, while the APC was 0.8% for glioblastoma, -2.0% for non-glioblastoma astrocytoma, 1.1% for oligodendroglial tumors, 0.7% for ependymoma and -0.3% for glioma NOS during the study period. Glioblastoma incidence increased for all tumor size and tumor extension except for distant. From 1995 to 2018, glioma mortality declined 0.4% per year (95% CI: -0.6% to -0.2%) but only increased in patients older than 80 years [APC=1.0%, (95% CI, 0.4% to 1.6%)].

Conclusion

Significant decline in glioma incidence (1987-2018) and mortality (1995-2018) were observed. Epidemiological changes in non-glioblastoma astrocytoma contributed the most to overall trends in glioma incidence and mortality. These findings can improve understanding of risk factors and guide the focus of glioma therapy.

Adherence to plant-based dietary patterns in relation to glioma: a case-control study

Available evidence suggests a favorable association between adherence to a plant-based diet and disease prevention, but data on the link between such dietary intakes and cancer are scarce. We examined the association between the overall plant-based diet (PDI), healthy plant-based diet (hPDI), and unhealthy plant-based diet (uPDI) and risk of glioma. This case–control study was conducted on 128 newly diagnosed glioma patients, and 256 hospital-based controls. Cases were diagnosed by pathological test and controls were selected from hospitalized people in orthopedic and surgical wards. Dietary intakes were assessed using a validated Block-format 123-items food frequency questionnaire. Scores of plant-based dietary patterns were calculated using the method suggested by Satija et al. After controlling for potential confounders, individuals with higher scores of PDI (OR: 0.54, 95% CI: 0.32–0.91, P-trend < 0.001) and hPDI (OR: 0.32, 95% CI: 0.18–0.57, P-trend < 0.001) had significantly lower odds of glioma compared with those with the lowest scores. This association did not change in the fully adjusted model; such that subjects in the highest tertile of PDI and hPDI were 69% and 71% less likely to have glioma compared with those in the lowest tertile. In contrast, higher scores of uPDI was significantly associated with a greater odds of glioma (OR: 2.85, 95% CI: 1.26–6.47, P-trend = 0.02). Adherence to PDI and hPDI was associated with a lower odds of glioma, while greater adherence to uPDI was directly associated with the likelihood of glioma. Further prospective cohort studies are needed to examine our findings.

Association between dietary glycemic index and glycemic load and glioma: a case-control study

OBJECTIVE

Although glycemic index (GI) and load (GL) have been linked with several health outcomes, no information is available linking dietary GI and GL with glioma. This study aimed to investigate the relationship between dietary GI and GL and odds of glioma.

METHODS

This hospital-based case-control study was conducted between November 2009 and September 2011 in the hospital affiliated to Shahid Beheshti University of Medical Sciences. We recruited 128 newly diagnosed cases of glioma and 256 age- and sex-matched controls. All cases were pathologically diagnosed with glioma patients, with no history of any type of other pathologically confirmed cancers and chemotherapy or radiotherapy (due to cancers). Dietary GI and GL were measured by using a validated, self-administered, dish-based, semi-quantitative food-frequency questionnaire.

RESULT

A significant positive association was found between dietary GI and glioma (OR: 3.01; 95% CI: 1.75-5.17, P < 0.001); such that after considering for potential confounders, participants in the highest tertile of dietary GI had 3.51 times greater risk of glioma than those in the lowest tertile (OR: 3.51; 95% CI: 1.69-7.28, P_trend = 0.001). Furthermore, we observed a significant positive association between dietary and glioma (OR: 3.74; 95% CI: 1.97-6.11, P_trend < 0.001). This association remained significant even after further controlling for potential confounders (OR: 2.42; 95% CI: 1.02-5.69, P_trend= 0.04).

DISCUSSION

We observed a significant positive association between dietary GI and GL and risk of glioma in adults. However, prospective cohort studies are required to confirm this association.

Alcohol intake and risk of glioma: results from three prospective cohort studies

PURPOSE

The association between alcohol intake and glioma remains unclear. We evaluated the association between alcohol intake and incidence of glioma in three large, prospective cohort studies with repeated alcohol assessments.

METHODS

We harnessed data from three studies with repeat alcohol assessment to compute hazard ratios (HR) and 95% confidence intervals (CI) for glioma by overall alcohol intake and intake from specific beverages using Cox proportional hazards regression, adjusted for age, cohort, body mass index, smoking status, and caloric intake. Analyses were conducted separately for glioma overall and for glioblastoma (GBM).

RESULTS

We confirmed 554 incident glioma cases (362 GBM) among 237,505 participants with 6,216,378 person-years of follow up. Cumulative average alcohol intake was associated with reduced risk of glioma (HR = 0.75, 95%CI:0.56-0.99 comparing > 8-15 to ≤ 0.5 g/d; HR = 0.71, 95%CI:0.53-0.96 comparing > 15 g/d to ≤ 0.5 g/d). When stratified by sex, for the same comparisons, the HRs for men were 0.57 (95%CI:0.36-0.89) and 0.79 (0.53-1.16), and for women 0.90 (95%CI:0.62-1.30) and 0.62, 95%CI:0.39-0.97. Results were consistent when examining cumulative average, baseline, and recent intake, and with a 4 year lag.

CONCLUSION

These results provide evidence against a positive association between alcohol intake and glioma risk. Alcohol intake was associated with reduced risk of glioma in both men and women.

Consumption of red meat and processed meat and cancer incidence: a systematic review and meta-analysis of prospective studies

Red meat and processed meat consumption has been hypothesized to increase risk of cancer, but the evidence is inconsistent. We performed a systematic review and meta-analysis of prospective studies to summarize the evidence of associations between consumption of red meat (unprocessed), processed meat, and total red and processed meat with the incidence of various cancer types. We searched in MEDLINE and EMBASE databases through December 2020. Using a random-effect meta-analysis, we calculated the pooled relative risk (RR) and 95% confidence intervals (CI) of the highest versus the lowest category of red meat, processed meat, and total red and processed meat consumption in relation to incidence of various cancers. We identified 148 published articles. Red meat consumption was significantly associated with greater risk of breast cancer (RR = 1.09; 95% CI = 1.03-1.15), endometrial cancer (RR = 1.25; 95% CI = 1.01-1.56), colorectal cancer (RR = 1.10; 95% CI = 1.03-1.17), colon cancer (RR = 1.17; 95% CI = 1.09-1.25), rectal cancer (RR = 1.22; 95% CI = 1.01-1.46), lung cancer (RR = 1.26; 95% CI = 1.09-1.44), and hepatocellular carcinoma (RR = 1.22; 95% CI = 1.01-1.46). Processed meat consumption was significantly associated with a 6% greater breast cancer risk, an 18% greater colorectal cancer risk, a 21% greater colon cancer risk, a 22% greater rectal cancer risk, and a 12% greater lung cancer risk. Total red and processed meat consumption was significantly associated with greater risk of colorectal cancer (RR = 1.17; 95% CI = 1.08-1.26), colon cancer (RR = 1.21; 95% CI = 1.09-1.34), rectal cancer (RR = 1.26; 95% CI = 1.09-1.45), lung cancer (RR = 1.20; 95% CI = 1.09-1.33), and renal cell cancer (RR = 1.19; 95% CI = 1.04-1.37). This comprehensive systematic review and meta-analysis study showed that high red meat intake was positively associated with risk of breast cancer, endometrial cancer, colorectal cancer, colon cancer, rectal cancer, lung cancer, and hepatocellular carcinoma, and high processed meat intake was positively associated with risk of breast, colorectal, colon, rectal, and lung cancers. Higher risk of colorectal, colon, rectal, lung, and renal cell cancers were also observed with high total red and processed meat consumption.

Severe consequences of a high-lipid diet include hydrogen sulfide dysfunction and enhanced aggression in glioblastoma

Glioblastoma (GBM) remains among the deadliest of human malignancies, and the emergence of the cancer stem cell (CSC) phenotype represents a major challenge to durable treatment response. Because the environmental and lifestyle factors that impact CSC populations are not clear, we sought to understand the consequences of diet on CSC enrichment. We evaluated disease progression in mice fed an obesity-inducing high-fat diet (HFD) versus a low-fat, control diet. HFD resulted in hyper-aggressive disease accompanied by CSC enrichment and shortened survival. HFD drove intracerebral accumulation of saturated fats, which inhibited the production of the cysteine metabolite and gasotransmitter, hydrogen sulfide (H2S). H2S functions principally through protein S-sulfhydration and regulates multiple programs including bioenergetics and metabolism. Inhibition of H2S increased proliferation and chemotherapy resistance, whereas treatment with H2S donors led to death of cultured GBM cells and stasis of GBM tumors in vivo. Syngeneic GBM models and GBM patient specimens present an overall reduction in protein S-sulfhydration, primarily associated with proteins regulating cellular metabolism. These findings provide clear evidence that diet modifiable H2S signaling serves to suppress GBM by restricting metabolic fitness, while its loss triggers CSC enrichment and disease acceleration. Interventions augmenting H2S bioavailability concurrent with GBM standard of care may improve outcomes for GBM patients.

An updated systematic review and meta-analysis on adherence to mediterranean diet and risk of cancer

PURPOSE

The aim of current systematic review was to update the body of evidence on associations between adherence to the Mediterranean diet (MedDiet) and risk of cancer mortality, site-specific cancer in the general population; all-cause, and cancer mortality as well as cancer reoccurrence among cancer survivors.

METHODS

A literature search for randomized controlled trials (RCTs), case-control and cohort studies published up to April 2020 was performed using PubMed and Scopus. Study-specific risk estimates for the highest versus lowest adherence to the MedDiet category were pooled using random-effects meta-analyses. Certainty of evidence from cohort studies and RCTs was evaluated using the NutriGrade scoring system.

RESULTS

The updated search revealed 44 studies not identified in the previous review. Altogether, 117 studies including 3,202,496 participants were enclosed for meta-analysis. The highest adherence to MedDiet was inversely associated with cancer mortality (RRcohort: 0.87, 95% CI 0.82, 0.92; N = 18 studies), all-cause mortality among cancer survivors (RRcohort: 0.75, 95% CI 0.66, 0.86; N = 8), breast (RRobservational: 0.94, 95% CI 0.90, 0.97; N = 23), colorectal (RRobservational: 0.83, 95% CI 0.76, 0.90; N = 17), head and neck (RRobservational: 0.56, 95% CI 0.44, 0.72; N = 9), respiratory (RRcohort: 0.84, 95% CI 0.76, 0.94; N = 5), gastric (RRobservational: 0.70, 95% CI 0.61, 0.80; N = 7), bladder (RRobservational: 0.87, 95% CI 0.76, 0.98; N = 4), and liver cancer (RRobservational: 0.64, 95% CI 0.54, 0.75; N = 4). Adhering to MedDiet did not modify risk of blood, esophageal, pancreatic and prostate cancer risk.

CONCLUSION

In conclusion, our results suggest that highest adherence to the MedDiet was related to lower risk of cancer mortality in the general population, and all-cause mortality among cancer survivors as well as colorectal, head and neck, respiratory, gastric, liver and bladder cancer risks. Moderate certainty of evidence from cohort studies suggest an inverse association for cancer mortality and colorectal cancer, but most of the comparisons were rated as low or very low certainty of evidence.

Searching for causal relationships of glioma: a phenome-wide Mendelian randomisation study

BACKGROUND

The aetiology of glioma is poorly understood. Summary data from genome-wide association studies (GWAS) can be used in a Mendelian randomisation (MR) phenome-wide association study (PheWAS) to search for glioma risk factors.

METHODS

We performed an MR-PheWAS analysing 316 phenotypes, proxied by 8387 genetic variants, and summary genetic data from a GWAS of 12,488 glioma cases and 18,169 controls. Causal effects were estimated under a random-effects inverse-variance-weighted (IVW-RE) model, with robust adjusted profile score (MR-RAPS), weighted median and mode-based estimates computed to assess the robustness of findings. Odds ratios per one standard deviation increase in each phenotype were calculated for all glioma, glioblastoma (GBM) and non-GBM tumours.

RESULTS

No significant associations (P < 1.58 × 10-4) were observed between phenotypes and glioma under the IVW-RE model. Suggestive associations (1.58 × 10-4 < P < 0.05) were observed between leukocyte telomere length (LTL) with all glioma (ORSD = 3.91, P = 9.24 × 10-3) and GBM (ORSD = 4.86, P = 3.23 × 10-2), but the association was primarily driven by the TERT variant rs2736100. Serum low-density lipoprotein cholesterol and plasma HbA1C showed suggestive associations with glioma (ORSD = 1.11, P = 1.39 × 10-2 and ORSD = 1.28, P = 1.73 × 10-2, respectively), both associations being reliant on single genetic variants.

CONCLUSIONS

Our study provides further insight into the aetiological basis of glioma for which published data have been mixed.

Nanodelivery Systems Targeting Epidermal Growth Factor Receptors for Glioma Management

A paradigm shift in treating the most aggressive and malignant form of glioma is continuously evolving; however, these strategies do not provide a better life and survival index. Currently, neurosurgical debulking, radiotherapy, and chemotherapy are the treatment options available for glioma, but these are non-specific in action. Patients invariably develop resistance to these therapies, leading to recurrence and death. Receptor Tyrosine Kinases (RTKs) are among the most common cell surface proteins in glioma and play a significant role in malignant progression; thus, these are currently being explored as therapeutic targets. RTKs belong to the family of cell surface receptors that are activated by ligands which in turn activates two major downstream signaling pathways via Rapidly Accelerating Sarcoma/mitogen activated protein kinase/extracellular-signal-regulated kinase (Ras/MAPK/ERK) and phosphatidylinositol 3-kinase/a serine/threonine protein kinase/mammalian target of rapamycin (PI3K/AKT/mTOR). These pathways are critically involved in regulating cell proliferation, invasion, metabolism, autophagy, and apoptosis. Dysregulation in these pathways results in uncontrolled glioma cell proliferation, invasion, angiogenesis, and cancer progression. Thus, RTK pathways are considered a potential target in glioma management. This review summarizes the possible risk factors involved in the growth of glioblastoma (GBM). The role of RTKs inhibitors (TKIs) and the intracellular signaling pathways involved, small molecules under clinical trials, and the updates were discussed. We have also compiled information on the outcomes from the various endothelial growth factor receptor (EGFR)-TKIs-based nanoformulations from the preclinical and clinical points of view. Aided by an extensive literature search, we propose the challenges and potential opportunities for future research on EGFR-TKIs-based nanodelivery systems.

The Influence of Nutritional and Lifestyle Factors on Glioma Incidence

Cancers are the first main cause of premature death in developed countries. Since brain tumors, especially gliomas, are the most lethal type of cancers, risk factors for their prevalence are still being discussed. Nearly 30–50% of all cancers could be prevented by proper nutritional habits and other lifestyle factors, but their influence on the tumors of the central nervous system has not been explained completely and still requires further studies. That is why we attempted to review the available research in this field, with a special focus on the factors with the proven protective activity observed in other cancers. Adequate vegetables and antioxidants (such as vitamins C and A) provided with a diet could have a protective effect, while other factors have shown no correlation with the incidence of glioma. However, further studies are necessary to determine whether fish, coffee, and tea consumption may prevent glioma. Maintaining proper body weight and undertaking a sufficient level of daily physical activity also seem to be important. Excessive body mass index (BMI) and higher attained height have increased the risk of glioma. In order to link more accurately the chosen factors to the prevalence of gliomas, it seems necessary to conduct large cohort, prospective, controlled studies in different world regions.

Adherence to the Mediterranean dietary pattern in relation to glioma: A case-control study

BACKGROUND

Although Mediterranean diet (MD) was associated with a lower risk of mortality and cancer, no data are available investigating the association between adherence to the MD and risk of glioma.

METHODS

In this case-control study, we enrolled a total of 128 newly diagnosed patients with glioma, confirmed by pathological assessment, and 256 hospital-based controls from 2009 to 2011 in Tehran, Iran. A valid and reliable Block-format food frequency questionnaire (FFQ) was used to assess dietary intakes. Adherence to the MD was examined using the scoring method suggested by Trichopoulou et al. Logistic regression was used to examine the associations of interest.

RESULTS

After controlling for age, sex, and energy intake, participants in the highest tertile of MD score had not significantly lower odds of glioma than those in the lowest tertile (OR: 0.58, 95% CI: 0.32-1.03, P_trend = 0.06). However, after taking other potential confounders into account, individuals with the greatest adherence to the MD score were 74% less likely to have glioma than those with the lowest adherence (OR: 0.26, 95% CI: 0.12-0.55, P_trend < 0.001). Additional adjustments for dietary intakes and BMI did not significantly alter this association (OR: 0.36, 95% CI: 0.16-0.78, P_trend = 0.009; OR: 0.36, 95% CI: 0.16-0.78, P_trend = 0.01, respectively).

CONCLUSION

We found that adherence to the MD was associated with a lower likelihood of having glioma. Prospective cohort studies are needed to further examine these findings.

A prospective study of coffee and tea consumption and the risk of glioma in the UK Biobank

BACKGROUND

Coffee and tea have been hypothesised to reduce the risk of some cancers; however, their impact on glioma is less well studied.

METHODS

We examined associations between self-reported intake of tea and coffee in relation to glioma risk in the UK Biobank. We identified 487 incident glioma cases among 379,259 participants. Hazard ratios (HR) and 95% confidence intervals (CI) for glioma according to caffeinated beverage consumption were calculated using Cox proportional hazards regression with adjustment for age, gender, race and education; daily cups of tea or coffee were included in models considering the other beverage.

RESULTS

Consuming 4 or more cups of tea was associated with reduced risk of glioma when compared to no tea consumption (HR = 0.69; 95% CI, 0.51-0.94). A significant inverse association was observed for glioblastoma (HR = 0.93 per 1 cup/d increment; 95% CI, 0.89-0.98) and among males for all gliomas combined (HR = 0.95 per 1 cup/d increment; 95% CI, 0.90-1.00). A suggestive inverse association was also observed with greater consumption of coffee (HR = 0.71; 95% CI, 0.49-1.05 for >4 versus 0 cups/d). Results were not materially changed with further adjustment for smoking, alcohol and body mass index. Associations were similar in 2-year and 3-year lagged analyses.

CONCLUSIONS

In this prospective study, we found a significant inverse association between tea consumption and the risk of developing glioma, and a suggestive inverse association for the consumption of coffee. Further investigation on the possible preventive role of caffeine in glioma is warranted.

Lack of association between modifiable exposures and glioma risk: a Mendelian randomization analysis

BACKGROUND

The etiological basis of glioma is poorly understood. We have used genetic markers in a Mendelian randomization (MR) framework to examine if lifestyle, cardiometabolic, and inflammatory factors influence the risk of glioma. This methodology reduces bias from confounding and is not affected by reverse causation.

METHODS

We identified genetic instruments for 37 potentially modifiable risk factors and evaluated their association with glioma risk using data from a genome-wide association study of 12 488 glioma patients and 18 169 controls. We used the estimated odds ratio of glioma associated with each of the genetically defined traits to infer evidence for a causal relationship with the following exposures:Lifestyle and dietary factors-height, plasma insulin-like growth factor 1, blood carnitine, blood methionine, blood selenium, blood zinc, circulating adiponectin, circulating carotenoids, iron status, serum calcium, vitamins (A1, B12, B6, E, and 25-hydroxyvitamin D), fatty acid levels (monounsaturated, omega-3, and omega-6) and circulating fetuin-A;Cardiometabolic factors-birth weight, high density lipoprotein cholesterol, low density lipoprotein cholesterol, total cholesterol, total triglycerides, basal metabolic rate, body fat percentage, body mass index, fasting glucose, fasting proinsulin, glycated hemoglobin levels, diastolic and systolic blood pressure, waist circumference, waist-to-hip ratio; andInflammatory factors- C-reactive protein, plasma interleukin-6 receptor subunit alpha and serum immunoglobulin E.

RESULTS

After correction for the testing of multiple potential risk factors and excluding associations driven by one single nucleotide polymorphism, no significant association with glioma risk was observed (ie, PCorrected > 0.05).

CONCLUSIONS

This study did not provide evidence supporting any of the 37 factors examined as having a significant influence on glioma risk.

Risk factors for childhood and adult primary brain tumors

Primary brain tumors account for ~1% of new cancer cases and ~2% of cancer deaths in the United States; however, they are the most commonly occurring solid tumors in children. These tumors are very heterogeneous and can be broadly classified into malignant and benign (or non-malignant), and specific histologies vary in frequency by age, sex, and race/ethnicity. Epidemiological studies have explored numerous potential risk factors, and thus far the only validated associations for brain tumors are ionizing radiation (which increases risk in both adults and children) and history of allergies (which decreases risk in adults). Studies of genetic risk factors have identified 32 germline variants associated with increased risk for these tumors in adults (25 in glioma, 2 in meningioma, 3 in pituitary adenoma, and 2 in primary CNS lymphoma), and further studies are currently under way for other histologic subtypes, as well as for various childhood brain tumors. While identifying risk factors for these tumors is difficult due to their rarity, many existing datasets can be leveraged for future discoveries in multi-institutional collaborations. Many institutions are continuing to develop large clinical databases including pre-diagnostic risk factor data, and developments in molecular characterization of tumor subtypes continue to allow for investigation of more refined phenotypes. Key Point 1. Brain tumors are a heterogeneous group of tumors that vary significantly in incidence by age, sex, and race/ethnicity.2. The only well-validated risk factors for brain tumors are ionizing radiation (which increases risk in adults and children) and history of allergies (which decreases risk).3. Genome-wide association studies have identified 32 histology-specific inherited genetic variants associated with increased risk of these tumors.

LncRNA RHPN1-AS1 Targeting miR-625/REG3A Promotes Cell Proliferation And Invasion Of Glioma Cells

Introduction

Glioma arises from the proliferation of neuroglial cells differentiated from the ectoderm. Evidence has confirmed that differentially expressed long non-coding RNAs (lncRNAs) may be involved in the development and progression of various tumors. The present study aimed to explore the biological function of lncRNA RHPN1-AS1 in glioma.

Materials and methods

The expressions of RHPN1-AS1 in glioma tissues and cells were examined using RT-PCR. Colony formation assay, MTT assay, wound healing assay and transwell assay were performed to detect cell cloning efficiency, proliferation, migration and invasion of glioma cells, respectively. Western blot was applied to assess the expression levels of migration-related and invasion-related proteins. Online bioinformatic tools and luciferase reporter assay were, respectively, employed to predict and verify the downstream target microRNA/gene of RHPN1-AS1.

Results

RHPN1-AS1 was up-regulated in glioma tissues and cells. The cell proliferation, migration and invasion of glioma were inhibited when the expression of RHPN1-AS1 was down-regulated in glioma cells. The expressions of migration-related and invasion-related proteins were also suppressed in siRHPN1-AS1 groups. Furthermore, we predicted and verified that RHPN1-AS1 was directly targeted to miR-625-5p/REG3A. Our study demonstrated that the knockdown of RHPN1-AS1 inhibited the proliferation, migration and invasion activity of glioma cells via regulating miR-625-5p/REG3A expression.

Conclusion

The results revealed that the lncRNA RHPN1-AS1 may be a molecular target in glioma therapy.