Dietary fats and their sources in association with the risk of bladder cancer: A pooled analysis of 11 prospective cohort studies

The association between animal protein, plant protein, and their substitution with bladder cancer risk: a pooled analysis of 10 cohort studies

PURPOSE

Although total dietary protein intake has been associated with bladder cancer (BC) risk, the effect of the origin (plant or animal) and the substitutions remain to be understood. This study aimed to investigate the effect of total dietary protein, animal-based protein, plant-based protein, and their substitutions with each other on the risk of BC using a pooled analysis of 10 cohort studies.

METHODS

The study was conducted within the "BLadder cancer Epidemiology and Nutritional Determinants" (BLEND) study, including 10 prospective cohort studies from several European countries, the United Kingdom, and the United States. Individual data from 10 prospective cohorts containing 434,412 participants (overall male/female ratio was almost 3:1) with a total of 4,224,643.8 person-years of follow-up was analyzed. Hazard ratios (HRs) and 95% confidence intervals (CIs) for BC risk for animal and plant-based protein substitutions of 30gram (g) per day (g/day) were estimated by multivariable adjusted HRs using Cox proportional hazards models.

RESULTS

During 11.4 years of follow-up, among 434,412 participants (73.28% female), 1,440 new cases of BC were identified. After multivariable adjustment, no association was observed between the intake of total, animal-based protein, and plant-based protein and BC risk. Replacement of every 30 g/day of animal-based protein intake by the same amount of plant-based protein intake or vice versa was not associated with the risk of BC.

CONCLUSION

In conclusion, our study found no association between protein intake-whether from animal or plant sources-and the risk of BC. Substituting animal-based protein with plant-based protein, or the reverse, did not influence BC risk. Future studies are required to provide information on the link between animal- and plant-based proteins and BC risk.

Cholesterol Metabolism and Urinary System Tumors

Cancers of the urinary system account for 13.1% of new cancer cases and 7.9% of cancer-related deaths. Of them, renal cancer, bladder cancer, and prostate cancer are most prevalent and pose a substantial threat to human health and the quality of life. Prostate cancer is the most common malignant tumor in the male urinary system. It is the second most common type of malignant tumor in men, with lung cancer surpassing its incidence and mortality. Bladder cancer has one of the highest incidences and is sex-related, with men reporting a significantly higher incidence than women. Tumor development in the urinary system is associated with factors, such as smoking, obesity, high blood pressure, diet, occupational exposure, and genetics. The treatment strategies primarily involve surgery, radiation therapy, and chemotherapy. Cholesterol metabolism is a crucial physiological process associated with developing and progressing urinary system tumors. High cholesterol levels are closely associated with tumor occurrence, invasion, and metastasis. This warrants thoroughly investigating the role of cholesterol metabolism in urinary system tumors and identifying novel treatment methods for the prevention, early diagnosis, targeted treatment, and drug resistance of urinary system tumors.

Olive oil intake and cardiovascular disease, cancer, and all-cause mortality: a systematic review and dose-response meta-analysis of prospective cohort studies

Background: Currently, the reported links between olive oil intake and cardiovascular disease (CVD), cancer morbidity and mortality, and all-cause mortality are inconsistent. The aim of this meta-analysis is to study the reported correlations of olive oil intake with CVD, coronary heart disease (CHD), stroke and cancer incidence and mortality, and all-cause mortality. Methods: PubMed, Embase, and Web of Science were searched until March 7, 2024. Pooled relative risks (RRs) and 95% confidence intervals (CIs) were estimated by the random-effects model. Nonlinear dose-response relationships were modeled with restricted cubic splines. This study has been registered at PROSPERO (CRD42023419001). Results: Overall, 30 articles covering 2 710 351 participants were identified. Higher olive oil intake was linked with a reduced risk of CVD incidence (RR: 0.85; 95% CI: 0.77, 0.93), CHD incidence (RR: 0.85; 95% CI: 0.72, 0.99), CVD mortality (RR: 0.77; 95% CI: 0.67, 0.88), and all-cause mortality (RR: 0.85; 95% CI: 0.81, 0.89). For a 10 g d-1 increment of olive oil intake, the risk of CVD incidence, stroke incidence, CVD mortality, and all-cause mortality decreased by 7%, 5%, 8%, and 8%, respectively. No association was found between olive oil intake and cancer incidence and mortality. Nonlinear relationships between olive oil intake and CVD and all-cause mortality were observed, with a reduced risk from intakes ranging from 0 to 18 g d-1 and 0 to 22 g d-1, respectively. Conclusion: Our study found that high olive oil intake was related to a lower risk of CVD and CHD incidence and CVD mortality and all-cause mortality.

C15:0 and C17:0 partially mediate the association of milk and dairy products with bladder cancer risk

The relationship between saturated fatty acids (SFA) and bladder cancer (BC) risk has been conflicting. Our aim was to investigate the relationship between erythrocyte membrane SFA and BC risk. A total of 404 participants were enrolled in the study (including 112 cases and 292 controls). A validated food frequency questionnaire was used to assess the food intake. The constitutive composition of fatty acids in the erythrocyte membrane was measured by gas chromatography. After adjustment for BC risk factors, SFA had no significant association with BC risk. However, C18:0 was positively linked with BC risk with an odds ratio (OR; 95% CI) of 2.99 (1.37-6.53). In contrast, very-long-chain saturated fatty acids (VLCSFA), especially C24:0, were negatively related to BC risk with an OR (95% CI) of 0.28 (0.12-0.65) for VLCSFA and 0.33 (0.15-0.75) for C24:0. Higher total odd-chain SFA (C15:0 and C17:0) were associated with a lower risk of BC with OR (95% CI) of 0.18 (0.076-0.44), 0.18 (0.068-0.47), 0.34 (0.14-0.81), respectively. After subgroup analysis, the protective effects C15:0 and C17:0 were still remained. Receiver operating characteristic analysis displayed that the combination of C15:0 and C17:0 indexes increased the accurate predictive rate of BC risk. Further mediation effect analysis showed that C15:0 and C17:0 could be used as partial mediation effectors for milk and dairy products and bladder carcinogenesis. Overall, the combination of odd-chain SFA (C15:0 and C17:0) in the erythrocyte membrane could serve as a reliable mediator and predictor, indicating a relationship between a high intake of milk and dairy products and a lower risk of BC.

Adherence to the Diabetes Risk Reduction Diet and Bladder Cancer Risk in the Prostate, Lung, Colorectal, Ovarian (PLCO) Cohort

BACKGROUND

This study aimed to explore the relationship between diabetes risk reduction diet (DRRD) and bladder cancer risk in Prostate, Lung, Colorectal, Ovarian (PLCO) cohort.

METHODS

Data from 99,001 participants in the PLCO Cancer Screening Trial were analyzed using Cox proportional hazards regression models to estimate HRs and 95% confidence intervals (CI) for the association between DRRD score and bladder cancer incidence. Subgroup analyses were conducted to assess whether variables such as age, sex, body mass index, cigarette smoking status, and history of diabetes influenced the observed association. The DRRD score was formulated on the basis of nine nutrient intake indicators derived from the Dietary History Questionnaire.

RESULTS

During the median follow-up of 11.7 years, 761 new bladder cancer cases were identified. Participants with highest DRRD scores exhibited a reduced risk of bladder cancer compared with those in the lowest quartile (unadjusted analysis, HR, 0.65; 95% CI, 0.53-0.82); multivariable adjusted analysis, HR, 0.79; 95% CI, 0.64-0.98; Ptrend = 0.007). A similar risk reduction was seen solely in transitional cell carcinoma (HR, 0.79; 95% CI, 0.64-0.99; P = 0.007). In addition, the significant negative association between DRRD scores and bladder cancer risk persisted even after excluding participants with unique characteristics.

CONCLUSIONS

This large prospective population-based study suggests that adherence to a DRRD may contribute to the prevention of bladder cancer.

IMPACT

The DRRD could potentially mitigate bladder cancer risk, which warrants further validation in diverse populations.

Shared genetic links between bladder cancer and obesity-related traits: A conjunctional false discovery rate study

Bladder cancer (BCa) is a common cancer worldwide and is often linked with obesity-related comorbidities, but little is known about the underlying genetic mechanisms. To investigate these mechanisms, we used various quantitative tools, including conditional quantile-quantile (Q-Q) plots, conditional false discovery rate (cFDR), and conjunctional conditional false discovery rate (ccFDR), to explore the pleiotropic enrichment of risk loci between BCa and obesity-related traits. We also performed an expression quantitative trait locus (eQTL) analysis to assess the relationship between shared risk loci and gene expression. Finally, we conducted functional annotation using Kyoto Encyclopedia of Genes and Genomes (KEGG) and gene ontology (GO) analysis. Our findings indicated that there was successive enrichment for a range of obesity-related traits, including body fat percentage, body mass index, fasting insulin, type 2 diabetes mellitus, fasting glucose, high-density lipoprotein cholesterol, total triglycerides, and waist-to-hip ratio. Using the tools mentioned above, we identified 18 significant SNPs and 18 closely related genes (cFDR<0.01) under the condition of 8 obesity-related traits. The SNPs included rs143004880, rs73301337, rs10798572, rs11594929, rs17019138, rs2877, rs149795948, rs142509736, rs12727575, rs1571277, rs12131828, rs635634, rs76895963, rs118081211, rs7044247, rs138895564, rs4135275, and rs148023060. Additionally, we identified 15 novel loci using ccFDR, including rs143004880, rs73301337, rs10798572, rs11594929, rs17019138, rs2877, rs142509736, rs1571277, rs635634, rs76895963, rs12131828, rs118081211, rs7044247, rs138895564, and rs4135275. Of the 2 significant loci that modify gene expression, rs12131828 and rs635634 were identified. The functional annotation indicated that the conditional risk genes mainly participated in the regulation of gene silencing. Our study provided evidence of pleiotropic enrichment between BCa and 8 obesity-related traits, and we identified potential genetic mechanisms underlying this relationship. These findings may help in developing targeted clinical treatments for BCa.

Relationship between Bladder Cancer, Nutritional Supply, and Treatment Strategies: A Comprehensive Review

Bladder cancer (BC) is the predominant neoplasm affecting the urinary system and ranks among the most widespread malignancies globally. The causes of bladder cancer include genetic factors; age; sex; and lifestyle factors, such as imbalanced nutrition, obesity, and metabolic disorders. The lack of proper nutrient intake leads to the development of bladder cancer because insufficient nutrients are consumed to prevent this disease. The purpose of this review was to analyze the nutrients closely linked to the onset and advancement of bladder cancer and to explore the relationship between dietary nutrients and bladder cancer. Particular emphasis was placed on nutrients that are frequently ingested in daily life, including sugar, fat, protein, and others. The focus of this research was to analyze how nutritional intake before and after surgery affects the recovery process of patients who have been diagnosed with bladder cancer. This article seeks to increase awareness among both society and the medical community about the significance of implementing appropriate dietary nutrition to reduce the chances of developing bladder cancer, enhance perioperative care for patients with bladder cancer, and aid in their recuperation.

Intermediate and high-risk non-muscle-invasive bladder cancer: an overview of epidemiology, burden, and unmet needs

Bladder cancer ranks among the most common cancers globally. At diagnosis, 75% of patients have non-muscle-invasive bladder cancer (NMIBC). Patients with low-risk NMIBC have a good prognosis, but recurrence and progression rates remain high in intermediate- and high-risk NMIBC, despite the decades-long availability of effective treatments for NMIBC such as intravesical Bacillus Calmette-Guérin (BCG). The present review provides an overview of NMIBC, including its burden and treatment options, and then reviews aspects that counteract the successful treatment of NMIBC, referred to as unmet treatment needs. The scale and reasons for each unmet need are described based on a comprehensive review of the literature, including insufficient adherence to treatment guidelines by physicians because of insufficient knowledge, training, or access to certain therapy options. Low rates of lifestyle changes and treatment completion by patients, due to BCG shortages or toxicities and adverse events as well as their impact on social activities, represent additional areas of potential improvement. Highly heterogeneous evidence for the effectiveness and safety of some treatments limits the comparability of results across studies. As a result, efforts are underway to standardize treatment schedules for BCG, but intravesical chemotherapy schedules remain unstandardized. In addition, risk-scoring models often perform unsatisfactorily due to significant differences between derivation and real-world cohorts. Reporting in clinical trials suffers from a lack of consistent outcomes reporting in bladder cancer clinical trials, paired with an under-representation of racial and ethnic minorities in many trials.

Prospective Study of Avocado Consumption and Cancer Risk in U.S. Men and Women

Avocados contain nutrients and phytochemicals that make it promising for cancer prevention, and chemopreventive properties have been demonstrated in prior studies. Prospective studies on avocado consumption and cancer risk have yet to be conducted. This study included data from 45,289 men in the Health Professionals Follow-Up Study (HPFS, 1986-2016) and 67,039 women in the Nurses' Health Study (NHS, 1986-2014). Avocado consumption was assessed using validated food frequency questionnaires every 4 years. Cox proportional hazards models calculated multivariable HRs and 95% confidence intervals (CI) for associations between avocado consumption and risk of total and site-specific cancers in each cohort. In HPFS, consumption of ≥1 weekly serving of avocados was associated with decreased risk of total (HR, 0.85; 95% CI, 0.80-0.91), colorectal (HR, 0.71; 95% CI, 0.59-0.85), lung (HR, 0.71; 95% CI, 0.57-0.90), and bladder cancer (HR, 0.72; 95% CI, 0.57-0.90). In NHS, avocado consumption was associated with increased risk of breast cancer (HR, 1.21; 95% CI, 1.07-1.37). No associations were observed between avocado consumption and risk of total cancer (HR, 1.06; 95% CI, 0.98-1.14) or other site-specific cancers in NHS. Considering the surprising breast cancer finding, analyses were repeated using data from 93,230 younger women in the parallel NHSII (1991-2017). In NHSII, avocado consumption was not associated with breast cancer risk (HR, 0.93; 95% CI, 0.76-1.13). Overall, avocado consumption may be associated with reduced risk of total and some site-specific cancers in men. The positive association with breast cancer risk in NHS was not seen in the younger NHSII.

PREVENTION RELEVANCE

The results of this prospective study suggest that avocado consumption may be associated with decreased risk of total and some site-specific cancers in men. See related Spotlight, p. 187.

Epidemiology, Screening, and Prevention of Bladder Cancer

CONTEXT

Bladder cancer (BC) represents a significant health problem due to the potential morbidity and mortality associated with disease burden, which has remained largely unaltered over time.

OBJECTIVE

To provide an expert collaborative review and describe the incidence, prevalence, and mortality of BC and to evaluate current evidence for BC screening and prevention.

EVIDENCE ACQUISITION

Data on the estimated incidence and mortality of BC for 2020 in 185 countries were derived from the International Agency for Research on Cancer GLOBOCAN database. A review of English-language articles published over the past 5 yr was conducted using PubMed/MEDLINE to identify risk factors in addition to contemporary evidence on BC screening and prevention.

EVIDENCE SYNTHESIS

BC is the tenth most common cancer worldwide, with 573 278 cases in 2020. BC incidence is approximately fourfold higher in men than women. Tobacco smoking remains the principal risk factor, accounting for approximately 50% of cases. There is insufficient evidence to recommend routine BC screening. However, targeted screening of high-risk individuals (defined according to smoking history or occupational exposure) may reduce BC mortality and should be the focus of prospective randomized trials. In terms of disease prevention, smoking cessation represents the most important intervention, followed by a reduction in exposure to occupational and environmental carcinogens.

CONCLUSIONS

BC confers a significant disease burden. An understanding of BC epidemiology and risk factors provides an optimal foundation for disease prevention and the care of affected patients.

PATIENT SUMMARY

Bladder cancer is the tenth most common cancer worldwide and is approximately four times more common among men than among women. The main risk factors are tobacco smoking, followed by exposure to carcinogens in the workplace or the environment. Routine screening is not currently recommended, but may be beneficial in individuals at high risk, such as heavy smokers. Primary prevention is extremely important, and smoking cessation represents the most important action for reducing bladder cancer cases and deaths.