Diabetes mellitus and incidence of kidney cancer: a meta-analysis of cohort studies

Associations between Diabetes Mellitus and Selected Cancers

Cancer is one of the major causes of mortality and is the second leading cause of death. Diabetes mellitus is a serious and growing problem worldwide, and its prevalence continues to grow; it is the 12th leading cause of death. An association between diabetes mellitus and cancer has been suggested for more than 100 years. Diabetes is a common disease diagnosed among patients with cancer, and evidence indicates that approximately 8-18% of patients with cancer have diabetes, with investigations suggesting an association between diabetes and some particular cancers, increasing the risk for developing cancers such as pancreatic, liver, colon, breast, stomach, and a few others. Breast and colorectal cancers have increased from 20% to 30% and there is a 97% increased risk of intrahepatic cholangiocarcinoma or endometrial cancer. On the other hand, a number of cancers and cancer therapies increase the risk of diabetes mellitus. Complications due to diabetes in patients with cancer may influence the choice of cancer therapy. Unfortunately, the mechanisms of the associations between diabetes mellitus and cancer are still unknown. The aim of this review is to summarize the association of diabetes mellitus with selected cancers and update the evidence on the underlying mechanisms of this association.

Causality of genetically determined metabolites on susceptibility to prevalent urological cancers: a two-sample Mendelian randomization study and meta-analysis

Background

Prevalent urological cancers, including kidney, prostate, bladder, and testicular cancers, contribute significantly to global cancer incidence and mortality. Metabolomics, focusing on small-molecule intermediates, has emerged as a tool to understand cancer etiology. Given the knowledge gap in this field, we employ a two-sample Mendelian randomization (MR) analysis to investigate the causal relationships between genetically determined metabolites (GDMs) and the susceptibility to four common urological cancers.

Methods

The study employs genome-wide association studies (GWAS) data from European populations, featuring the most extensive case count available for both blood metabolites and four prevalent urological cancers. Preliminary and secondary MR analyses were separately conducted, employing inverse variance weighted (IVW) as the primary method. Multiple statistical analyses, including the MR-Steiger test, Cochran's Q test, leave-one-out analysis, MR-Egger intercept analysis, and MR-PRESSO analysis, were executed to ensure robustness. Additionally, a meta-analysis was carried out to consolidate findings. The weighted median (WM) method was utilized for a relatively lenient correction (PWM < 0.05).

Results

After rigorous genetic variation filtering, 645 out of 1,400 metabolites were included in both preliminary and secondary MR analyses. Preliminary MR analysis identified 96 potential causal associations between 94 distinct metabolites and four urological cancers. Secondary analysis based on Finnish outcome data revealed 93 potential causal associations. Cross-database meta-analysis identified 68 blood metabolites associated with four urological cancers. Notably, 31 metabolites remained significant after using WM for correction, with additional 37 suggestive causal relationships. Reverse MR analysis revealed a significant causal association between genetically predicted prostate cancer and elevated 4-hydroxychlorothalonil levels (IVW, combined OR: 1.039, 95% CI 1.014-1.064, p = 0.002; WM, combined OR: 1.052, 95% CI 1.010-1.095, p = 0.014).

Conclusion

This comprehensive MR study provides insights into the causal relationships between blood metabolites and urological cancers, revealing potential biomarkers and therapeutic targets, thereby addressing gaps in understanding and laying the foundation for targeted interventions in urological cancer research and treatment.

The causal relationship between smoking, alcohol consumption, and renal clear cell carcinoma: a Mendelian randomization study

Introduction: Observational studies have found a correlation between the consumption of tobacco and alcohol and the likelihood of developing renal cell carcinoma. However, whether these associations indicate causal relationships is unclear. Methods: To establish if these connections indicate causal relationships, we performed a Mendelian Randomization (MR) analysis using a two-sample approach. For the number of daily cigarettes, lifetime smoking index, smoking initiation, and weekly drinking, we employed 44, 108, 174, and 76 single nucleotide polymorphisms (SNPs) as instrumental variables. Outcome data were obtained from the FinnGen Alliance, which included a combined total of 429,290 individuals. The MR analysis was conducted using the inverse-variance weighted (IVW) method to estimate causal effects. To address potential violations of MR assumptions due to directional pleiotropy, we performed MR-Egger regression and MR-PRESSO (Mendelian Randomization Pleiotropy RESidual Sum and Outlier) analysis. Results: Genetically influenced smoking initiation was directly associated with the risk of developing renal cell carcinoma (OR = 1.55, 95% CI: 1.04-2.33; p = 0.03). No causal relationship was found between daily cigarette consumption and lifetime smoking index with the risk of renal cell cancer. Genetic predisposition for weekly alcohol consumption showed a reduced risk of renal cell cancer (OR = 0.45, 95% CI: 0.26-0.81; p = 0.007). Discussion: Our study suggests a potential causal relationship between alcohol consumption and reduced risk of renal cell cancer, while no such association was observed with smoking. Further research is needed to confirm these findings.

Association between diabetes and subsequent malignancy risk among older breast cancer survivors

Type II diabetes is associated with cancer risk in the general population but has not been well studied as a risk factor for subsequent malignancies among cancer survivors. We investigated the association between diabetes and subsequent cancer risk among older (66-84 years), 1-year breast cancer survivors within the linked Surveillance Epidemiology and End Results (SEER)-Medicare database using Cox regression analyses to quantify hazard ratios (HR) and corresponding 95% confidence intervals (95% CI). Among 133 324 women, 29.3% were diagnosed with diabetes before or concurrent with their breast cancer diagnosis, and 10 452 women developed subsequent malignancies over a median follow-up of 4.3 years. Diabetes was statistically significantly associated with liver (HR = 2.35, 95% CI = 1.48 to 3.74), brain (HR = 1.94, 95% CI = 1.26 to 2.96), and thyroid cancer risks (HR = 1.38, 95% CI = 1.01 to 1.89). Future studies are needed to better understand the spectrum of subsequent cancers associated with diabetes and the role of diabetes medications in modifying subsequent cancer risk, alone or in combination with cancer treatments.

Metabolic dysfunction-associated profiles and subsequent site-specific risk of obesity-related cancers among Chinese patients with diabetes: a retrospective cohort study

OBJECTIVES

To compare metabolic dysfunction-associated profiles between patients with diabetes who developed different obesity-related site-specific cancers and those who remained free of cancer during follow-up.

DESIGN

Retrospective cohort study.

SETTING

Public general outpatient clinics in Hong Kong.

PARTICIPANTS

Patients with diabetes without a history of malignancy (n=391 921).

PRIMARY OUTCOME MEASURES

The outcomes of interest were diagnosis of site-specific cancers (colon and rectum, liver, pancreas, bladder, kidney and stomach) during follow-up. Cox proportional hazards regression was applied to assess the associations between metabolic dysfunction and other clinical factors with each site-specific cancer.

RESULTS

Each 0.1 increase in waist-to-hip ratio was associated with an 11%-35% elevated risk of colorectal, bladder and liver cancers. Each 1% increase in glycated haemoglobin was linked to a 4%-9% higher risk of liver and pancreatic cancers. While low-density lipoprotein cholesterol and triglycerides were inversely associated with the risk of liver and pancreatic cancers, high-density lipoprotein cholesterol was negatively associated with pancreatic, gastric and kidney cancers, but positively associated with liver cancer. Furthermore, liver cirrhosis was linked to a 56% increased risk of pancreatic cancer. No significant association between hypertension and cancer risk was found.

CONCLUSIONS

Metabolic dysfunction-associated profiles contribute to different obesity-related cancer outcomes differentially among patients with diabetes. This study may provide evidence to help identify cancer prevention targets during routine diabetes care.

Tracing the pathways and mechanisms involved in medicinal uses of flaxseed with computational methods and bioinformatics tools

Pharmacological drugs targeting specific pathways involved in various diseases have seen recent advancement with newer and more efficient emerging drug targets, but these drugs are limited in terms of their side effects and patient adherence. The potential of plant-based diets in the form of functional foods is increasingly being realized as an option to treat and/or prevent several diseases. In this work, we have selected flaxseed (Linum usitatissimum), also known as linseed, to study its pharmacological efficacy and proposed mechanisms of action for medicinal purposes. The target genes of linseed with Disease Specificity Index (DSI >0.6) are compared to the associated genes of diabetes mellitus, decrease in appetite, addictive behavior, cardiovascular diseases (CVDs), inflammatory bowel diseases (IBDs), and Polycystic Ovary Syndrome (PCOS), and the selected genes are further evaluated using in silico methods. The binding affinity of flaxseed to three common target proteins (CCDC28b, PDCD6IP, and USP34) is assessed by docking and molecular dynamics (MD) simulations. The results show that linseed is safe to use for mutagenic toxicity and other cardiotoxicity measures, but linseed is unsafe for embryotoxicity, hERG toxicity, and cardiac failure. The analysis of the protein-protein interaction (PPI) network, Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways indicates that flaxseed can be used as a medicinal herb for treatment of diabetes mellitus, cardiovascular diseases, IBDs, and PCOS.

Meta-analysis of the Relationship between Type 2 Diabetes Mellitus and Renal Cancer Risk

OBJECTIVE

This study aimed to investigate the relationship between type 2 diabetes mellitus and the risk of renal cancer.

METHODS

A search was carried out on PubMed, Embase, Web of Science, China Biology Medicine disc (CBM), China National Knowledge Infrastructure (CNKI), Wanfang and other databases. The search period was from 2000 to 2022. The two authors independently conducted literature screening, extracted literature data, and then conducted a literature quality evaluation. The type of study is a cohort study. Meta-analysis was carried out on the included literature through Stata12.0 software, and the combined value was calculated with RR value and 95% confidence interval. Subgroup analysis was carried out to explore the impact of different factors on the overall results.

RESULTS

A total of 10 articles were included. Through cohort study, the meta-analysis on the risk of type 2 diabetes and renal cancer showed that the combined effect value Risk Ratio (RR) = 1.57 with 95% Confidence Intervals (CI) (1.36, 1.82) and P<0.05. The difference had a significant impact, indicating that the risk of renal cancer in type 2 diabetes patients was 1.55 times higher than that in non-type 2 diabetes patients. The subgroup analysis showed that the combined effect value RR and 95% CI for men was 1.49 (1.26, 1.75), and the combined effect value RR and 95% CI for women was 1.60 (1.35, 1.88), which was basically consistent.

CONCLUSION

Type 2 diabetes can significantly increase the risk of renal cell carcinoma, and the former is a risk factor for the latter. It is suggested that multi-center studies with larger sample sizes should be conducted in the future, and adjustments should be made according to the type of diabetes, the source of the study population, the pathological type of renal cell carcinoma, the use of hypoglycemic drugs, and other factors, to provide a reliable basis for the study of the relationship between diabetes and renal cell carcinoma. At present, the specific mechanism of diabetes increasing the risk of renal cell carcinoma and whether diabetes increases mortality due to renal cell carcinoma is still unclear and needs further research.

Associations of dietary patterns with kidney cancer risk, kidney cancer-specific mortality and all-cause mortality among postmenopausal women

BACKGROUND

The empirical dietary index for hyperinsulinemia (EDIH) and empirical dietary inflammatory pattern (EDIP) are novel measures of dietary quality associated with insulin hypersecretion or chronic inflammation, respectively, whereas the Healthy Eating Index (HEI-2015) measures adherence to the Dietary Guidelines for Americans (DGA). We evaluated associations of EDIH, EDIP and HEI-2015 on the risk of both kidney cancer development and mortality.

METHODS

We calculated the dietary scores from baseline food frequency questionnaires among 115,830 participants aged 50-79 years in the Women's Health Initiative. Multivariable-adjusted Cox regression was used to estimate hazard ratios (HR) and 95% confidence intervals (95%CI) for kidney cancer risk, kidney cancer-specific mortality and all-cause mortality, per 1-standard deviation increment in dietary pattern scores.

RESULTS

Higher EDIH was associated with greater risk of kidney cancer development [HR, 1.12; 95%CI, (1.01,1.23)], kidney cancer-specific death [1.22(0.99,1.48)], and all-cause mortality, [1.05(1.02,1.08)]. Higher HEI-2015 was associated with lower risk of kidney cancer development, [0.85(0.77, 0.94)], kidney cancer-specific death, [0.84(0.69,1.03)] and all-cause mortality, [0.97(0.95,1.00)]. However, EDIP was not significantly associated with outcomes. Associations did not differ by BMI categories.

CONCLUSIONS

Low-insulinemic dietary patterns and higher quality diets, are worthy of testing in dietary pattern intervention trials for kidney cancer prevention and improved survivorship.

The impact of diabetes status on total and site-specific cancer risk in the elderly population: A nationwide cohort study

AIMS

We aimed to evaluate the association of prediabetes, diabetes, and diabetes duration with risk of total and site-specific cancer in the Korean population aged 65 years and above.

METHODS

This study included 1,232,173 subjects aged ≥ 65 years who underwent a general health screening program. Diabetes status was categorized as normal glucose tolerance, impaired fasting glucose, new-onset diabetes, diabetes duration of < 5 years, and diabetes duration of ≥ 5 years. Cox proportional hazards models were used to investigate the association of diabetes status with cancer risk.

RESULTS

The risk of total cancer increased as diabetes status worsened, as did the risks of liver, biliary, and pancreatic cancer. Risks of liver, biliary, and pancreatic cancer were significantly higher in subjects aged 65-74 years than in those aged ≥ 75 years. The relationship of diabetes status with overall cancer incidence was found to significantly interact with sex. Among subjects with diabetes, the risks of liver and lung cancer were significantly higher in men than in women regardless of diabetes duration.

CONCLUSIONS

Diabetes status is associated with increased risk of cancer in the elderly. There are age and sex differences in the risk of total and site-specific cancers, including liver, biliary, and pancreatic cancer. This study highlights the importance of cancer screening for elderly subjects with diabetes.

Impairment of kidney function and kidney cancer: A bidirectional Mendelian randomization study

BACKGROUND

Many observational epidemiology studies discovered that kidney cancer and impaired kidney function have a bidirectional relationship. However, it remains unclear whether these two kinds of traits are causally linked. In this study, we aimed to investigate the bidirectional causal relation between kidney cancer and kidney function biomarkers (creatinine-based estimated glomerular filtration rate (eGFRcrea), cystatin C-based estimated glomerular filtration rate (eGFRcys), blood urea nitrogen (BUN), serum urate, and urinary albumin-to-creatinine ratio (UACR)).

METHODS

For both directions, single-nucleotide polymorphisms (SNPs), as genetic instruments, for the five kidney function traits were selected from up to 1,004,040 individuals, and SNPs for kidney cancer were from 408,786 participants(1338 cases). In the main analysis, we applied two state-of-the-art MR methods, namely, contamination mixture and Robust Adjusted Profile Score to downweight the effect of weak instrument bias, pleiotropy, and extreme outliers. We additionally conducted traditional MR analyses as sensitivity analyses. Summary-level data of European ancestry were extracted from UK Biobank, Chronic Kidney Disease Genetics Consortium, and Kaiser Permanente.

RESULTS

Based on 99 SNPs, we found that the eGFRcrea had a significant negative causal effect on the risk of kidney cancer (OR = 0.007, 95% CI:2.6 × 10-4 -0.569, p = 0.041). After adjusting for body composition or diabetes, urate had a significant negative causal effect on kidney cancer (OR <1, p < 0.05). For UACR, it showed a strong causal effect on kidney cancer, after adjusting for body composition (OR = 14.503, 95% CI: 2.546-96.001, p = 0.032). Due to lacking significant signals and effect power for the reverse MR, further investigations are warranted.

CONCLUSIONS

Our study suggested a potential causal effect of damaged kidney function on kidney cancer. EGFRcrea and UACR might be causally associated with kidney cancer, especially when patients were comorbid with obesity or diabetes. We called for larger sample-size studies to further unravel the underlying causal relationship and the exact mechanism.

Association between diabetes and cancer. Current mechanistic insights into the association and future challenges

Compelling pieces of epidemiological, clinical, and experimental research have demonstrated that Diabetes mellitus (DM) is a major risk factor associated with increased cancer incidence and mortality in many human neoplasms. In the pathophysiology context of DM, many of the main classical actors are relevant elements that can fuel the different steps of the carcinogenesis process. Hyperglycemia, hyperinsulinemia, metabolic inflammation, and dyslipidemia are among the classic contributors to this association. Furthermore, new emerging actors have received particular attention in the last few years, and compelling data support that the microbiome, the epigenetic changes, the reticulum endoplasmic stress, and the increased glycolytic influx also play important roles in promoting the development of many cancer types. The arsenal of glucose-lowering therapeutic agents used for treating diabetes is wide and diverse, and a growing body of data raised during the last two decades has tried to clarify the contribution of therapeutic agents to this association. However, this research area remains controversial, because some anti-diabetic drugs are now considered as either promotors or protecting elements. In the present review, we intend to highlight the compelling epidemiological shreds of evidence that support this association, as well as the mechanistic contributions of many of these potential pathological mechanisms, some controversial points as well as future challenges.

Burden of kidney cancer and attributed risk factors in China from 1990 to 2019

Background

The changing trends and risk-attributed burdens of kidney cancer in China are unknown. Therefore, this study aimed to describe the latest status and trends of kidney cancer burden in China and its associated risk factors.

Methods

The absolute numbers and rates of the incidence, deaths, and disability-adjusted life-years (DALYs) of kidney cancer in China were extracted from the Global Burden of Disease 2019 platform. Overall burden and burden attributed to smoking and high body mass index (BMI) were described. Average annual percent change (AAPC) was calculated to describe trend analyses from 1990 to 2019 using the Joinpoint regression program.

Results

In 2019, 59,827 new cases, 23,954 deaths, and 642,799 DALYs of kidney cancer occurred in China, of which men accounted for 71.1, 70.5, and 72.0%, and the population aged ≥55 years accounted for 58.9, 77.9, and 60.1%, of new cases, deaths, and DALYs, respectively. From 1990 to 2019, the age-standardized incidence rate (per 100,000 person-years) increased from 1.16 in 1990 to 3.21 in 2019, with an AAPC of 3.4% (95% confidence interval [CI]: 3.1-3.8%, p < 0.05); the mortality rate increased from 0.70 to 1.27, with an AAPC of 2.1% (1.5-2.3%, p < 0.05); and the DALY rate increased from 0.70 to 1.27, with an AAPC of 2.1% (1.5-2.3%, p < 0.05). In 2019, the proportions of DALYs attributed to smoking and high BMI were 18.0% and 11.1%, respectively, and the DALY rates attributed to both smoking and high BMI increased from 1990 to 2019, with AAPC of 2.9% (2.6-3.3%, p < 0.05) and 4.8% (4.2-5.4%, p < 0.05), respectively.

Conclusion

The kidney cancer burden in China has continued to grow over the recent three decades, with a severe burden among older adults and men. Therefore, timely preventive interventions for modifiable risk factors are required.

Long term exposure to air pollution and kidney parenchyma cancer - Effects of low-level air pollution: a Study in Europe (ELAPSE)

BACKGROUND

Particulate matter (PM) is classified as a group 1 human carcinogen. Previous experimental studies suggest that particles in diesel exhaust induce oxidative stress, inflammation and DNA damage in kidney cells, but the evidence from population studies linking air pollution to kidney cancer is limited.

METHODS

We pooled six European cohorts (N = 302,493) to assess the association of residential exposure to fine particles (PM2.5), nitrogen dioxide (NO2), black carbon (BC), warm season ozone (O3) and eight elemental components of PM2.5 (copper, iron, potassium, nickel, sulfur, silicon, vanadium, and zinc) with cancer of the kidney parenchyma. The main exposure model was developed for year 2010. We defined kidney parenchyma cancer according to the International Classification of Diseases 9th and 10th Revision codes 189.0 and C64. We applied Cox proportional hazards models adjusting for potential confounders at the individual and area-level.

RESULTS

The participants were followed from baseline (1985-2005) to 2011-2015. A total of 847 cases occurred during 5,497,514 person-years of follow-up (average 18.2 years). Median (5-95%) exposure levels of NO2, PM2.5, BC and O3 were 24.1 μg/m3 (12.8-39.2), 15.3 μg/m3 (8.6-19.2), 1.6 10-5 m-1 (0.7-2.1), and 87.0 μg/m3 (70.3-97.4), respectively. The results of the fully adjusted linear analyses showed a hazard ratio (HR) of 1.03 (95% confidence interval [CI]: 0.92, 1.15) per 10 μg/m³ NO2, 1.04 (95% CI: 0.88, 1.21) per 5 μg/m³ PM2.5, 0.99 (95% CI: 0.89, 1.11) per 0.5 10-5 m-1 BCE, and 0.88 (95% CI: 0.76, 1.02) per 10 μg/m³ O3. We did not find associations between any of the elemental components of PM2.5 and cancer of the kidney parenchyma.

CONCLUSION

We did not observe an association between long-term ambient air pollution exposure and incidence of kidney parenchyma cancer.

The burden and risks of emerging complications of diabetes mellitus

The traditional complications of diabetes mellitus are well known and continue to pose a considerable burden on millions of people living with diabetes mellitus. However, advances in the management of diabetes mellitus and, consequently, longer life expectancies, have resulted in the emergence of evidence of the existence of a different set of lesser-acknowledged diabetes mellitus complications. With declining mortality from vascular disease, which once accounted for more than 50% of deaths amongst people with diabetes mellitus, cancer and dementia now comprise the leading causes of death in people with diabetes mellitus in some countries or regions. Additionally, studies have demonstrated notable links between diabetes mellitus and a broad range of comorbidities, including cognitive decline, functional disability, affective disorders, obstructive sleep apnoea and liver disease, and have refined our understanding of the association between diabetes mellitus and infection. However, no published review currently synthesizes this evidence to provide an in-depth discussion of the burden and risks of these emerging complications. This Review summarizes information from systematic reviews and major cohort studies regarding emerging complications of type 1 and type 2 diabetes mellitus to identify and quantify associations, highlight gaps and discrepancies in the evidence, and consider implications for the future management of diabetes mellitus.

Biochemical mechanism underlying the pathogenesis of diabetic retinopathy and other diabetic complications in humans: the methanol-formaldehyde-formic acid hypothesis

Hyperglycemia in diabetic patients is associated with abnormally-elevated cellular glucose levels. It is hypothesized that increased cellular glucose will lead to increased formation of endogenous methanol and/or formaldehyde, both of which are then metabolically converted to formic acid. These one-carbon metabolites are known to be present naturally in humans, and their levels are increased under diabetic conditions. Mechanistically, while formaldehyde is a cross-linking agent capable of causing extensive cytotoxicity, formic acid is an inhibitor of mitochondrial cytochrome oxidase, capable of inducing histotoxic hypoxia, ATP deficiency and cytotoxicity. Chronic increase in the production and accumulation of these toxic one-carbon metabolites in diabetic patients can drive the pathogenesis of ocular as well as other diabetic complications. This hypothesis is supported by a large body of experimental and clinical observations scattered in the literature. For instance, methanol is known to have organ- and species-selective toxicities, including the characteristic ocular lesions commonly seen in humans and non-human primates, but not in rodents. Similarly, some of the diabetic complications (such as ocular lesions) also have a characteristic species-selective pattern, closely resembling methanol intoxication. Moreover, while alcohol consumption or combined use of folic acid plus vitamin B is beneficial for mitigating acute methanol toxicity in humans, their use also improves the outcomes of diabetic complications. In addition, there is also a large body of evidence from biochemical and cellular studies. Together, there is considerable experimental support for the proposed hypothesis that increased metabolic formation of toxic one-carbon metabolites in diabetic patients contributes importantly to the development of various clinical complications.

Association Between Diabetes and the Risk of Kidney Cancer: Systematic Review and Meta-Analysis

Diabetes is a risk factor for several types of cancer, but the specific relationship between diabetes and kidney cancer is not well understood. We conducted a search strategy in scientific databases for case-control and cohort studies on this topic. We analyzed 17 studies and found that diabetes was significantly associated with the risk of developing kidney cancer and that this risk was slightly stronger for women and for people living in Asia. These findings were not influenced by obesity, cigarette smoking, or hypertension. We conclude that diabetes is an independent risk factor for the development of kidney cancer.

The association between diabetes and cancer in Mexico: Analysis using death certificate databases, 2009-2017

Context

Previous studies have shown that diabetes mellitus (DM) is a risk factor of some type-specific cancers. However, no data are available on the association between cancer and DM in Latin America.

Aims

The aim of this study is to determine which type-specific cancers are associated with DM using multiple cause of death data.

Settings and Design

Whole country of Mexico, cross-sectional design.

Materials and Methods

Analysis of all cancer deaths (2009-2017) using death certificate databases of Mexican adults aged ≥20 years.

Statistical Analysis Used

Multivariable logistic regression.

Results

There were 710,292 total cancer deaths. DM increased the risk of pancreatic (adjusted odds ratio [aOR] = 1.7), liver (aOR = 1.6), kidney (aOR = 1.4), gallbladder (aOR = 1.2) and endometrial (aOR = 1.1) cancers, all P < 0.05. Type 2 or unknown-type DM were associated with the same cancer types with little variation of estimates. Higher estimates were found in males than females (except for kidney cancer). Type 1 DM was associated with pancreatic cancer only (aOR = 1.9).

Conclusions

DM in Mexico is associated with gastrointestinal (pancreatic, liver, gallbladder), kidney and endometrial cancers. Dissemination of knowledge to both health-care workers and diabetics regarding potential cancer risks including adequate diet, regular exercise, weight reduction if obese/overweight, cessation of smoking, and good glucose control and medication compliance should be reinforced. Specific cancer preventative measures should be implemented for patients with DM.

Sugary drink consumption and risk of kidney and bladder cancer in Japanese adults

Globally, sugary drinks are widely consumed, however, few epidemiologic studies have investigated the association between sugary drink consumption and risk of kidney and bladder cancer. We examined the association of sugary drinks with risk of kidney and bladder cancer in 73,024 participants from the Japan Public Health Center-based Prospective Study who reported no history of cancer. Sugary drink consumption was assessed using a validated food frequency questionnaire at study baseline (1995–1999). Individuals were followed to December 31, 2013. Multivariable Cox proportional hazards regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CIs). During 1,069,815 person years of follow-up, 169 kidney cancer and 297 bladder cancer cases were documented. After adjusting for potential confounders, no greater risk of kidney and bladder cancer was observed. However, sugary drink consumption was positively associated with the risk of kidney cancer (HR for 100 ml/day increase in consumption was 1.11 [95% CI 1.01–1.22]) and bladder cancer (HR for 100 ml/d increase in consumption was 1.11 [95% CI 1.01–1.22]) among women after exclusion of cases diagnosed in the first three years of follow-up. In this large prospective cohort, consumption of sugary drinks was significantly associated with a small increase in hazard ratio for kidney and bladder cancer among women after exclusion of cases diagnosed within the first three years.

Association Between Genetically Proxied Lipid-Lowering Drug Targets and Renal Cell Carcinoma: A Mendelian Randomization Study

Observational studies suggested inconsistent associations between lipid-lowering drugs, such as statins, and renal cell carcinoma (RCC) risk. In a two-sample Mendelian randomization (MR) framework, we assessed the causal influence of lipid-lowering agents and circulating lipid traits on overall and sex-specific RCC risk. Genetic variants of six drug-target genes were selected to proxy the effects of low-density lipoprotein cholesterol (LDL-C) lowering therapies. Instrumental variables for circulating lipid traits were constructed from two large genome-wide association studies. We used endpoints for RCC from summary statistics of two studies [International Agency for Research on Cancer [IARC], N = 13,230; National Cancer Institute [NCI], N = 4,735]. The robustness of results was assessed through conventional MR sensitivity analyses. Overall, there was no significant association between genetically proxied HMG-CoA reductase (HMGCR) inhibition and RCC risk [Odds ratio [OR] = 1.42, 95% CI, 0.29–6.99]. In the sex-stratified analysis, we observed a positive association for genetically proxied drug targets with RCC risk. Specifically, genetically proxied proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition was associated with a higher risk of RCC in men [OR = 2.20 [95% CI, 1.24–3.89]], and the difference by sex was moderate. This study suggested genetically proxied inhibition of HMGCR was not associated with RCC risk, while genetically proxied PCSK9 inhibition might be associated with a higher risk of RCC in male.

Cancer mortality in a population-based cohort of American Indians - The strong heart study

BACKGROUND

Cancer mortality among American Indian (AI) people varies widely, but factors associated with cancer mortality are infrequently assessed.

METHODS

Cancer deaths were identified from death certificate data for 3516 participants of the Strong Heart Study, a population-based cohort study of AI adults ages 45-74 years in Arizona, Oklahoma, and North and South Dakota. Cancer mortality was calculated by age, sex and region. Cox proportional hazards model was used to assess independent associations between baseline factors in 1989 and cancer death by 2010.

RESULTS

After a median follow-up of 15.3 years, the cancer death rate per 1000 person-years was 6.33 (95 % CI 5.67-7.04). Cancer mortality was highest among men in North/South Dakota (8.18; 95 % CI 6.46-10.23) and lowest among women in Arizona (4.57; 95 % CI 2.87-6.92). Factors independently associated with increased cancer mortality included age, current or former smoking, waist circumference, albuminuria, urinary cadmium, and prior cancer history. Factors associated with decreased cancer mortality included Oklahoma compared to Dakota residence, higher body mass index and total cholesterol. Sex was not associated with cancer mortality. Lung cancer was the leading cause of cancer mortality overall (1.56/1000 person-years), but no lung cancer deaths occurred among Arizona participants. Mortality from unspecified cancer was relatively high (0.48/100 person-years; 95 % CI 0.32-0.71).

CONCLUSIONS

Regional variation in AI cancer mortality persisted despite adjustment for individual risk factors. Mortality from unspecified cancer was high. Better understanding of regional differences in cancer mortality, and better classification of cancer deaths, will help healthcare programs address cancer in AI communities.

Cancer and diabetes: the interlinking metabolic pathways and repurposing actions of antidiabetic drugs

Cancers are regarded as one of the main causes of death and result in high health burden worldwide. The management of cancer include chemotherapy, surgery and radiotherapy. The chemotherapy, which involves the use of chemical agents with cytotoxic actions is utilised as a single treatment or combined treatment. However, these managements of cancer such as chemotherapy poses some setbacks such as cytotoxicity on normal cells and the problem of anticancer drug resistance. Therefore, the use of other therapeutic agents such as antidiabetic drugs is one of the alternative interventions used in addressing some of the limitations in the use of anticancer agents. Antidiabetic drugs such as sulfonylureas, biguanides and thiazolidinediones showed beneficial and repurposing actions in the management of cancer, thus, the activities of these drugs against cancer is attributed to some of the metabolic links between the two disorders and these includes hyperglycaemia, hyperinsulinemia, inflammation, and oxidative stress as well as obesity. Furthermore, some studies showed that the use of antidiabetic drugs could serve as risk factors for the development of cancerous cells particularly pancreatic cancer. However, the beneficial role of these chemical agents overweighs their detrimental actions in cancer management. Hence, the present review indicates the metabolic links between cancer and diabetes and the mechanistic actions of antidiabetic drugs in the management of cancers.

Alcohol consumption, tobacco smoking, and subsequent risk of renal cell carcinoma: The JPHC study

The effects of alcohol consumption and tobacco smoking on renal cell carcinoma (RCC) incidence have not been well‐investigated in Asian populations. Here, we evaluated these effects in a large Japanese prospective cohort. We collected data on eligible participants in the Japan Public Health Center‐based Prospective Study, and undertook multivariable‐adjusted Cox proportional hazards regression to estimate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) of RCC incidence. We identified 340 cases (230 men and 110 women) among the 105 663 eligible participants (50 262 men and 55 741 women), who were followed for an average of 19.1 years, with a cumulative total of 2 020 364 person‐years. A slightly inverse but nonsignificant association was observed between alcohol drinking and RCC incidence. In contrast, the risk of RCC was increased in those with heavy smoking (≥40 pack‐years) when men and women were combined (HR 1.50; 95% CI, 1.01‐2.25). We identified no significant association between alcohol consumption and RCC incidence. In contrast, heavy smoking (≥40 pack‐years) was associated with a significant increase in incidence.

Using a large prospective cohort in Japan, we evaluated the effects of alcohol consumption and tobacco smoking on renal cell carcinoma (RCC). Our analyses showed no significant association between alcohol consumption and RCC incidence. In contrast, heavy smoking (≥40 pack‐years) was associated with a significant increase in incidence.

From kidney injury to kidney cancer

Epidemiologic studies document strong associations between acute or chronic kidney injury and kidney tumors. However, whether these associations are linked by causation, and in which direction, is unclear. Accumulating data from basic and clinical research now shed light on this issue and prompt us to propose a new pathophysiological concept with immanent implications in the management of patients with kidney disease and patients with kidney tumors. As a central paradigm, this review proposes the mechanisms of kidney damage and repair that are active during acute kidney injury but also during persistent injuries in chronic kidney disease as triggers of DNA damage, promoting the expansion of (pre-)malignant cell clones. As renal progenitors have been identified by different studies as the cell of origin for several benign and malignant kidney tumors, we discuss how the different types of kidney tumors relate to renal progenitors at specific sites of injury and to germline or somatic mutations in distinct signaling pathways. We explain how known risk factors for kidney cancer rather represent risk factors for kidney injury as an upstream cause of cancer. Finally, we propose a new role for nephrologists in kidney cancer (i.e., the primary and secondary prevention and treatment of kidney injury to reduce incidence, prevalence, and recurrence of kidney cancer).

High circulating insulin-like growth factor-1 reduces the risk of renal cell carcinoma: a Mendelian randomization study

Insulin and insulin-like growth factors play important roles in carcinogenesis. Circulating insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-binding protein-3 (IGFBP-3) have been linked to cancer susceptibility. The associations of circulating IGF-1 and IGFBP-3 with the risk of renal cell carcinoma (RCC) are inconsistent. Recent large genome-wide association studies have identified 413 single nucleotide polymorphisms (SNPs) associated with IGF-1 and 4 SNPs associated with IGFBP-3. In this large case-control study consisting of 2069 RCC patients and 2052 healthy controls of European ancestry, we used a two-sample Mendelian randomization (MR) approach to investigate the associations of genetically predicted circulating IGF-1 and IGFBP-3 with RCC risk. We used an individual level data-based genetic risk score (GRS) and a summary statistics-based inverse-variance weighting (IVW) method in MR analyses. We found that genetically predicted IGF-1 was significantly associated with RCC risk in both the GRS analysis [odds ratio (OR) = 0.43 per SD increase, 95% confidence interval (CI), 0.34-0.53] and the IVW analysis (OR = 0.46 per SD increase, 95% CI, 0.37-0.57). Dichotomized at the median GRS value of IGF-1 in controls, individuals with high GRS had a 45% reduced RCC risk (OR = 0.55, 95% CI, 0.48-0.62) compared with those with low GRS. Genetically predicted circulating IGFBP-3 was not associated with RCC risk. This is the largest RCC study of circulating IGF-1 and IGFBP-3 to date and our data suggest a strong inverse relationship between circulating IGF-1 level and RCC risk.

Possible role of the receptor of advanced glycation end products (RAGE) in the clinical course of prostate neoplasia in patients with and without type 2 diabetes mellitus

AIM

The expression of the cognate receptor of advanced glycation end products (RAGE) in malignant tissues of patients with type 2 diabetes has been suggested as a co-factor determining the clinical course and prognosis. We aimed to investigate the relationship between RAGE expression and clinicopathological features of prostate neoplasia.

METHODS

Tissue samples of 197 patients, 64 (24 patients with type 2 diabetes and 40 controls) with benign prostate hyperplasia (BPH) and 133 (71 patients with type 2 diabetes and 62 controls) with localised or metastatic prostate cancer (LPCa/MetPCa) were included in the study. The expression of RAGE in prostate specimens was studied immunohistochemically. RAGE scores were determined according to the extent of immunoreactivity and staining intensity.

RESULTS

RAGE expression in BPH group (patients with type 2 diabetes and controls) was negative. Patients with both LPCa and MetPCa had significantly higher scores than those with BPH (P < .001). The mean RAGE scores of patients with type 2 diabetes LPCa and MetPCa were 4.71 ± 3.14 and 4.97 ± 3.69. The mean scores of control LPCa and MetPCa were 1.52 ± 1.87 and 1.69 ± 1.58, respectively. The scores of patients with type 2 diabetes LPCa and MetPCa were significantly higher than those of control LPCa and MetPCa (P = .01 and P < .001, respectively).

CONCLUSION

We found higher RAGE expression levels in malignant prostate neoplasia than in BPH. As expected, patients with diabetes had higher scores than control patients. Disease progression and survival parameters were worse in patients with high RAGE levels. RAGE expression may be a useful biomarker for the diagnosis and prognosis of prostate cancer.

Metformin and Malignant Tumors: Not Over the Hill

Malignant tumors are a major cause of death, and their incidence is increasing worldwide. Although the survival rate for some cancers has improved, treatments for other malignant tumors are limited, and their mortality rate continues to increase. People with type 2 diabetes have a higher risk of malignant tumors and a higher mortality rate than those without diabetes. Metformin is a commonly used hypoglycemic drug. In recent years, a growing number of studies have indicated that metformin has antitumor effects and increases the sensitivity of malignant tumors to chemotherapy. However, the effect of metformin on different tumors is currently controversial, and the mechanism of metformin's antitumor action is not fully understood. Insights into the effect of metformin on malignant tumors and the possible mechanism may contribute to the development of antitumor drugs.

Annual glycemic variations and risk of cancer among Chinese patients with type 2 diabetes mellitus: A population-based cohort study in Shanghai

BACKGROUND

Long-term glycemic variation in diabetes patients may have contributed to cancer incidence.

AIM

In this study we aimed at the association between annual glycemic variation and the risk of cancer in Chinese patients with type 2 diabetes mellitus (T2DM).

METHODS

Subjects of this study were from an established population-based cohort of T2DM patients in Minhang District of Shanghai, China. Incident cancer were obtained from the Shanghai Cancer Registry. Glycemic variation was evaluated using the annual fasting glucose coefficient of variation (FG-CV), which was used as a time-dependent variable in a Cox regression model to estimate the associations with the cancer risk. Restricted cubic splines were used to explore potential non-linear associations.

RESULTS

A total of 2,140 incident cancers (1100 men and 1040 women) were identified from the 46,202 diabetes patients during 12-year follow-up. The annual FG-CV remained significantly associated with an increased risk of cancer, even after adjusting for the annual mean FG level. A significant non-linear association was found in male T2DM patients, and a significant linear association in female patients.

CONCLUSIONS

The positive association of the annual FG-CV with the risk of cancer in T2DM patients indicate the importance to stabilize the FG level.

Bioinformatic gene analysis for potential biomarkers and therapeutic targets of diabetic nephropathy associated renal cell carcinoma

Background

Numerous epidemiological studies have confirmed that diabetes can promote the development of malignant tumors. However, the relationship between renal cell carcinoma (RCC) and diabetic nephropathy (DN) is still controversial. This study aimed to investigate the genes that are co-expressed in DN and RCC in order to gain a better understanding of the relationship between these diseases, and to identify potential biomarkers and targets for the treatment of DN-related RCC.

Methods

We evaluated the differentially expressed genes (DEGs) that are co-expressed in DN and RCC using a wide range of target prediction and analysis methods. Twenty-four genes were identified by intersecting the differential genes of 3 DN datasets and 2 RCC datasets. We predicted the micro-ribonucleic acids (miRNAs) of these genes that may be controlled using the miRNA Data Integration Portal (mirDIP) database, and rated them according to each data forecast based on the Comparative Toxicogenomics Database (CTD) and the StarBase database.

Results

Four genes were associated with DN and RCC patients: the predicted miRNAs hsa-miR-200b-3p and hsa-miR-429 of fibronectin 1 (FN1); the predicted miRNA hsa-miR-29c-3p of collagen type 1 alpha 2 (COL1A2); the predicted miRNA hsa-miR-29c-3p of collagen type 3 alpha 1 (COL3A1); and the predicted miRNA hsa-miR-29a-3p and hsa-miR-200c-3p of glucose-6-phosphatase catalytic subunit (G6PC). These genes may serve as potential biomarkers or specific targets in the treatment of DN-related RCC.

Conclusions

A significant correlation was identified between DN and RCC. The FN1, COL1A2, COL3A1, and G6PC genes could be novel biomarkers of DN-related RCC.

Increased kidney cancer risk in diabetes mellitus patients: a population-based cohort study in Lithuania

BACKGROUND

Diabetes is associated with increased risk of various cancers but its association with kidney cancer is unclear. The objective of this study was to evaluate the association between T2DM with or without metformin use and the risk of kidney cancer in a population-based national cohort in Lithuania.

METHODS

The cohort was composed of diabetic patients identified in the NHIF database during 2000-2012. Cancer cases were identified by record linkage with the national Cancer Registry. Standardized incidence ratios (SIRs) for kidney cancer as a ratio of observed number of cancer cases in diabetic patients to the expected number of cancer cases in the underlying general population were calculated.

RESULTS

T2DM patients (11,592) between 2000 and 2012 were identified. Overall, 598 cases of primary kidney cancer were identified versus 393.95 expected yielding an overall SIR of 1.52 (95% CI: 1.40-1.64). Significantly higher risk was found in males and females. Significantly higher risk of kidney cancer was also found in both metformin users and never-users' groups (SIRs 1.45, 95% CI: 1.33-1.60 and 1.78 95% CI: 1.50-2.12, respectively).

CONCLUSIONS

The patients with T2DM have higher risk for kidney cancer compared with the general Lithuanian population.

Glycemic control and the incidence of neoplasm in patients with type 2 diabetes: a meta-analysis of randomized controlled trials

PURPOSE

Previous epidemiologic studies indicate an increased risk of cancer and cancer mortality in patients with type 2 diabetes (T2D). Whether the resolution of hyperglycemia will lead to reduced risk of neoplasm in T2D remains uncertain. Therefore, we performed a meta-analysis to assess the association between glycemic control and incidence of neoplasm in T2D patients.

METHODS

Randomized controlled trials (RCTs) in T2D with significant HbA1c reduction difference between intensive/active and standard/control groups plus follow-up ≥48 weeks were included and analyzed by fixed-effect models, random-effect model, and meta-regression analysis accordingly.

RESULTS

Overall, 52 studies were included. Compared with standard/control treatment, intensive/active treatment led to significantly greater HbA1c reduction from baseline (WMD = -0.51%, 95% CI, -0.55 to -0.46%, P < 0.001), but was not associated with a decreased incidence of neoplasm (OR = 0.99, 95% CI, 0.94-1.03, I² = 2%) in T2D. Meta-regression analysis indicated that HbA1c reduction difference between intensive/active treatment and standard/control treatment was not associated with the incidence of neoplasm in T2D patients (β = -0.0011, 95% CI, -0.0058 to 0.0035, P = 0.625). In neoplasm-site subgroup analysis, a decreased incidence of breast neoplasm was observed in T2D patients using dipeptidyl-peptidase-4 inhibitor (OR = 0.56, 95% CI, 0.35-0.89, I² = 0%) and incidence of prostate neoplasm was reduced in T2D patients with glucagon-like peptide-1 receptor agonist treatment (OR = 0.66, 95% CI, 0.47-0.91, I² = 0%).

CONCLUSION

Improved glycemic control in short and medium periods achieved by existing glucose-lowering drugs or strategies may not confer reduced risk of neoplasm in patients with T2D. Studies with longer follow-up duration are needed to better elucidate the long-period effects.

Association of Type 2 Diabetes With Cancer: A Meta-analysis With Bias Analysis for Unmeasured Confounding in 151 Cohorts Comprising 32 Million People

BACKGROUND AND PURPOSE

Whether the association between type 2 diabetes (T2D) and cancer is causal remains controversial. The goal of this work is to assess the robustness of the observational associations between T2D and cancer to unmeasured confounding.

DATA SOURCES AND STUDY SELECTION

PubMed, Web of Science, and the Cochrane library were systematically searched on 10 January 2019 for observational studies investigating associations between T2D and cancer incidence or mortality.

DATA EXTRACTION AND DATA SYNTHESIS

Cohort-level relative risk (RR) was extracted. RRs were combined in random-effects meta-analyses and pooled estimates used in bias analyses. A total of 151 cohorts (over 32 million people, 1.1 million cancer cases, and 150,000 cancer deaths) were included. In meta-analyses, T2D was associated with incidence of several cancers, from prostate (RR 0.83; 95% CI 0.79, 0.88) to liver (2.23; 1.99, 2.49), and with mortality from pancreatic cancer (1.67; 1.30, 2.14). In bias analyses, assuming an unmeasured confounding associated with both T2D and cancer with a RR of 1.5, the proportion of studies with a true effect size larger than a RR of 1.1 (i.e., 10% increased risk in individuals with T2D) was nearly 100% for liver, pancreatic, and endometrial, 86% for gallbladder, 67% for kidney, 64% for colon, 62% for colorectal, and <50% for other cancer incidences, and 92% for pancreatic cancer mortality.

LIMITATIONS

Biases other than unmeasured confounding were not analytically assessed.

CONCLUSIONS

Our findings strongly suggest a causal association between T2D and liver, pancreatic, and endometrial cancer incidence, and pancreatic cancer mortality. Conversely, associations with other cancers were less robust to unmeasured confounding.

The burden of kidney cancer and its attributable risk factors in 195 countries and territories, 1990-2017

Kidney cancer globally accounts for more than 131,000 deaths each year and has been found to place a large economic burden on society. However, there are no recent articles on the burden of kidney cancer across the world. The aim of this study was to present a status report on the incidence, mortality and disability-adjusted life years (DALYs) associated with kidney cancer in 195 countries, from 1990 to 2017. Vital registration and cancer registry data (total of 23,660 site-years) were used to generate the estimates. Mortality was estimated first and the incidence and DALYs were calculated based on the estimated mortality values. All estimates were presented as counts and age-standardised rates per 100,000 population. The estimated rates were calculated by age, sex and according to the Socio-Demographic Index (SDI). In 2017, kidney cancer accounted for 393.0 thousand (95% UI: 371.0-404.6) incident cases, 138.5 thousand (95% UI: 128.7-142.5) deaths and 3.3 million (95% UI: 3.1-3.4) DALYs globally. The global age-standardised rates for the incidence, deaths and DALY were 4.9 (95% UI: 4.7-5.1), 1.7 (95% UI: 1.6-1.8) and 41.1 (95% UI: 38.7-42.5), respectively. Uruguay [15.8 (95% UI: 13.6-19.0)] and Bangladesh [1.5 (95% UI: 1.0-1.8)] had highest and lowest age-standardised incidence rates, respectively. The age-standardised death rates varied substantially from 0.47 (95% UI: 0.34-0.58) in Bangladesh to 5.6 (95% UI: 4.6-6.1) in the Czech Republic. Incidence and mortality rates were higher among males, than females, across all age groups, with the highest rates for both sexes being observed in the 95+ age group. Generally, positive associations were found between each country's age-standardised DALY rate and their corresponding SDI. The considerable burden of kidney cancer was attributable to high body mass index (18.5%) and smoking (16.6%) in both sexes. There are large inter-country differences in the burden of kidney cancer and it is generally higher in countries with a high SDI. The findings from this study provide much needed information for those in each country that are making health-related decisions about priority areas, resource allocation, and the effectiveness of prevention programmes. The results of our study also highlight the need for renewed efforts to reduce exposure to the kidney cancer risk factors and to improve the prevention and the early detection of this disease.

Diabetes and kidney cancer risk among post-menopausal women: The Iowa women's health study

BACKGROUND

Many studies have reported a positive association between diabetes and kidney cancer. However, it is unclear whether diabetes is a risk factor for kidney cancer independent of other risk factors, such as obesity and hypertension. We comprehensively examined the association of diabetes and its duration with incident kidney cancer in the prospective cohort Iowa Women's Health Study (1986-2011).

METHODS

Diabetes status was self-reported at baseline (1986) and on five follow-up questionnaires. Cox proportional hazards regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations of baseline and time-dependent diabetes with the risk of incident kidney cancer.

RESULTS

During the 25 years of follow-up, 245 cases of kidney cancer occurred among 36,975 post-menopausal women. In an age-adjusted model, there was a significant association between time-dependent diabetes and the risk of kidney cancer [HR (95% CI) = 1.76 (1.26, 1.45)]; the association was attenuated after multivariable adjustment for age, body mass index (BMI), waist-to-hip ratio (WHR), hypertension, physical activity, diuretic use, pack-years of smoking, alcohol intake, and total caloric intake [HR = 1.35 (0.94, 1.94)]. However, among non-obese women or women with a waist circumference less than 34.6 in., diabetes was significantly associated with kidney cancer risk: for time-dependent diabetes, HRs (95% CIs) were 1.82 (1.10, 3.00) among those with BMI < 30 kg/m² and 2.18 (1.08, 4.38) among those with a waist circumference <34.6 in..

CONCLUSIONS

Our results suggest that diabetes is associated with kidney cancer risk among non-obese post-menopausal women.

Is Type 2 Diabetes Causally Associated With Cancer Risk? Evidence From a Two-Sample Mendelian Randomization Study

We conducted a two-sample Mendelian randomization study to investigate the causal associations of type 2 diabetes mellitus (T2DM) with risk of overall cancer and 22 site-specific cancers. Summary-level data for cancer were extracted from the Breast Cancer Association Consortium and UK Biobank. Genetic predisposition to T2DM was associated with higher odds of pancreatic, kidney, uterine, and cervical cancer and lower odds of esophageal cancer and melanoma but not associated with 16 other site-specific cancers or overall cancer. The odds ratios (ORs) were 1.13 (95% CI 1.04, 1.22), 1.08 (1.00, 1.17), 1.08 (1.01, 1.15), 1.07 (1.01, 1.15), 0.89 (0.81, 0.98), and 0.93 (0.89, 0.97) for pancreatic, kidney, uterine, cervical, and esophageal cancer and melanoma, respectively. The association between T2DM and pancreatic cancer was also observed in a meta-analysis of this and a previous Mendelian randomization study (OR 1.08; 95% CI 1.02, 1.14; P = 0.009). There was limited evidence supporting causal associations between fasting glucose and cancer. Genetically predicted fasting insulin levels were positively associated with cancers of the uterus, kidney, pancreas, and lung. The current study found causal detrimental effects of T2DM on several cancers. We suggest reinforcing the cancer screening in T2DM patients to enable the early detection of cancer.

Dietary fiber, glycemic index, glycemic load and renal cell carcinoma risk

Several epidemiological studies have investigated the potential association between dietary fiber, glycemic index (GI) or glycemic load (GL), and renal cell carcinoma (RCC) risk with inconsistent results. The aim of this study was to systematically evaluate this issue with a meta-analysis approach. A comprehensive literature search up to March 2018 was performed in PubMed and Web of Science databases. Summary relative risks (RRs) and 95% confidence intervals (CIs) were estimated with a random-effects model. Twelve studies were finally included in this study (eight for fiber analysis, five for GI and five for GL). A significant positive association was observed between GI and the risk of RCC (summary RR 1.16, 95% CI 1.02-1.32), and no significant heterogeneity was detected among studies (I2 = 22.8%, P = 0.262). A significant inverse association was found between fiber intake and the risk of RCC (summary RR 0.82, 95% CI 0.72-0.92), and no significant heterogeneity was observed across studies (I2 = 27.6%, P = 0.218). GL was not significantly associated with RCC risk (summary RR 1.14, 95% CI 0.81-1.60), and significant heterogeneity was found across studies (I2 = 78.6%, P < 0.001). In conclusion, this systematic review and meta-analysis suggests that dietary GI and fiber may be associated with the risk of RCC. Further large prospective cohort studies are still warranted to confirm our preliminary findings.

Validation of risk factors for recurrence of renal cell carcinoma: Results from a large single-institution series

PURPOSE

To validate prognostic factors and determine the impact of obesity, hypertension, smoking and diabetes mellitus (DM) on risk of recurrence after surgery in patients with localized renal cell carcinoma (RCC).

MATERIALS AND METHODS

We performed a retrospective cohort study among patients that underwent partial or radical nephrectomy at Weill Cornell Medicine for RCC and collected preoperative information on RCC risk factors, as well as pathological data. Cases were reviewed for radiographic evidence of RCC recurrence. A Cox proportional-hazards model was developed to determine the contribution of RCC risk factors to recurrence risk. Disease-free survival and overall survival were analyzed using the Kaplan-Meier method and log-rank test.

RESULTS

We identified 873 patients who underwent surgery for RCC between the years 2000-2015. In total 115 patients (13.2%) experienced a disease recurrence after a median follow up of 4.9 years. In multivariate analysis, increasing pathological T-stage (HR 1.429, 95% CI 1.265-1.614) and Nuclear grade (HR 2.376, 95% CI 1.734-3.255) were independently associated with RCC recurrence. In patients with T1-2 tumors, DM was identified as an additional independent risk factor for RCC recurrence (HR 2.744, 95% CI 1.343-5.605). Patients with DM had a significantly shorter median disease-free survival (1.5 years versus 2.6 years, p = 0.004), as well as median overall survival (4.1 years, versus 5.8 years, p<0.001).

CONCLUSIONS

We validated high pathological T-stage and nuclear grade as independent risk factors for RCC recurrence following nephrectomy. DM is associated with an increased risk of recurrence among patients with early stage disease.

Pre-existing type 2 diabetes is an adverse prognostic factor in patients with renal cell carcinoma

BACKGROUND

Diabetes is a risk factor for various cancers, but its prognostic role in renal cell carcinoma (RCC) is controversial and understudied. This study investigated the prognostic value of type 2 diabetes (T2D) in RCC patients.

METHODS

The clinicopathological and follow-up data of 451 RCC patients undergoing radical or partial nephrectomy at the First Hospital of Shanxi Medical University from 2013 to 2018 were reviewed. Associations of T2D with clinicopathological parameters of RCC were evaluated using the Kaplan-Meier method for survival estimates and Cox regression univariate and multivariate analyses.

RESULTS

Of 451 patients, 74 (16.4%) had T2D. These patients were older, had a higher body mass index, higher incidence rates of hypertension and cardiovascular morbidity, a higher rate of laparoscopic surgery, and smaller neoplasms (all P < .05). Patients with T2D exhibited shorter overall survival (OS; P = .009), cancer-specific survival (CSS; P = .043), and recurrence-free survival (RFS; P = .008) than patients without T2D. Fuhrman grade (hazard ratio [HR] 2.542, 95% confidence interval [CI] 1.115-5.795, P = .026) and T2D (HR 3.391, CI 1.458-7.886, P = .005) were independent predictors of OS; T2D was an independent predictor of CSS (HR = 4.637, 95% CI 1.420-15.139, P = .011) and RFS (HR 3.492, 95% CI 1.516-8.044, P = .003).

CONCLUSIONS

Renal cell carcinoma patients with T2D have a shorter OS and higher recurrence rate and mortality risk than those without T2D.

The long-term rapid increase in incidence of adenocarcinoma of the kidney in the USA, especially among younger ages

BACKGROUND

We previously observed a rapid increase in the incidence of renal cell carcinoma (RCC) in men and women between 1935 and 1989 in the USA, using data from the Connecticut Tumor Registry. This increase appeared to be largely explained by a positive cohort effect, but no population-based study has been conducted to comprehensively examine age-period-cohort effects by histologic types for the past decade.

METHODS

We calculated age-adjusted and age-specific incidence rates of the two major kidney-cancer subtypes RCC and renal urothelial carcinoma, and conducted an age-period-cohort analysis of 114 138 incident cases of kidney cancer reported between 1992 and 2014 to the Surveillance, Epidemiology, and End Results programme.

RESULTS

The age-adjusted incidence rates of RCC have been increasing consistently in the USA among both men and women (from 12.18/100 000 in 1992-1994 to 18.35/100 000 in 2010-2014 among men; from 5.77/100 000 in 1992-1994 to 8.63/100 000 in 2010-2014 among women). Incidence rates generally increased in successive birth cohorts, with a continuing increase in rates among the younger age groups (ages 0-54 years) in both men and women and among both Whites and Blacks. These observations were confirmed by age-period-cohort modelling, which suggested an increasing birth-cohort trend for RCC beginning with 1955 birth cohorts, regardless of the assumed value for the period effect for both men and women and for Whites and Blacks.

CONCLUSIONS

Known risk factors for kidney cancer may not fully account for the observed increasing rates or the birth-cohort pattern for RCC, prompting the need for additional etiologic hypotheses (such as environmental exposures) to investigate these descriptive patterns.

Diabetes and cancer: A comprehensive review

Diabetes mellitus (DM) is a common worldwide endocrine disorder characterized by hyperglycemia resulting from defects in insulin secretion and insulin action or both. A number of clinical studies have investigated diabetes and its causal relation with neoplasm. Several epidemiological studies have found that diabetic patients have an increased risk of different types of cancers, for example liver, pancreas, gastric (stomach), colorectum, kidney, and breast, and it is predicted that hyperglycemic state observed in diabetic milieu enhances the cancer risk in prediabetic and diabetic individuals. To explore the strength of evidence and biases in the claimed associations between type 2 DM (T2DM) and risk of developing cancer, an umbrella review of the evidence across published meta-analyses or systematic reviews is performed. The concurrence of T2DM with the growing burden of cancer globally has generated interest in defining the epidemiological and biological relationships between these medical conditions. Through this review, it was found that diabetes could be related to cancer. Yet, the results from most of the studies are obscure and conflicting and need a robust research so that the link between diabetes and cancer could be firmly and impeccably documented.

Diabetic lung disease: fact or fiction?

Diabetes mellitus is a chronic, progressive, incompletely understood metabolic disorder whose prevalence has been increasing steadily worldwide. Even though little attention has been paid to lung disorders in the context of diabetes, its prevalence has recently been challenged by newer studies of disease development. In this review, we summarize and discuss the role of diabetes mellitus involved in the progression of pulmonary diseases, with the main focus on pulmonary fibrosis, which represents a chronic and progressive disease with high mortality and limited therapeutic options.

Hyperglycemia-Induced Aberrant Cell Proliferation; A Metabolic Challenge Mediated by Protein O-GlcNAc Modification

Chronic hyperglycemia has been associated with an increased prevalence of pathological conditions including cardiovascular disease, cancer, or various disorders of the immune system. In some cases, these associations may be traced back to a common underlying cause, but more often, hyperglycemia and the disturbance in metabolic balance directly facilitate pathological changes in the regular cellular functions. One such cellular function crucial for every living organism is cell cycle regulation/mitotic activity. Although metabolic challenges have long been recognized to influence cell proliferation, the direct impact of diabetes on cell cycle regulatory elements is a relatively uncharted territory. Among other "nutrient sensing" mechanisms, protein O-linked β-N-acetylglucosamine (O-GlcNAc) modification emerged in recent years as a major contributor to the deleterious effects of hyperglycemia. An increasing amount of evidence suggest that O-GlcNAc may significantly influence the cell cycle and cellular proliferation. In our present review, we summarize the current data available on the direct impact of metabolic changes caused by hyperglycemia in pathological conditions associated with cell cycle disorders. We also review published experimental evidence supporting the hypothesis that O-GlcNAc modification may be one of the missing links between metabolic regulation and cellular proliferation.

Sex differences in the association between diabetes and risk of cardiovascular disease, cancer, and all-cause and cause-specific mortality: a systematic review and meta-analysis of 5,162,654 participants

BACKGROUND

Studies have suggested sex differences in the mortality rate associated with diabetes. We conducted a meta-analysis to estimate the relative effect of diabetes on the risk of all-cause, cancer, cardiovascular disease (CVD), infectious disease, and respiratory disease mortality in women compared with men.

METHODS

Studies published from their inception to April 1, 2018, identified through a systematic search of PubMed and EMBASE and review of references. We used the sex-specific RRs to derive the women-to-men ratio of RRs (RRR) and 95% CIs from each study. Subsequently, the RRR for each outcome was pooled with random-effects meta-analysis weighted by the inverse of the variances of the log RRRs.

RESULTS

Forty-nine studies with 86 prospective cohorts met the inclusion criteria and were eligible for analysis. The pooled women-to-men RRR showed a 13% greater risk of all-cause mortality associated with diabetes in women than in men (RRR 1.13, 95% CI 1.07 to 1.19; P < 0.001). The pooled multiple-adjusted RRR indicated a 30% significantly greater excess risk of CVD mortality in women with diabetes compared with men (RRR 1.30, 95% CI 1.13 to 1.49; P < 0.001). Compared with men with diabetes, women with diabetes had a 58% greater risk of coronary heart disease (CHD) mortality, but only an 8% greater risk of stroke mortality (RRR_CHD 1.58, 95% CI 1.32 to 1.90; P < 0.001; RRR_stroke 1.08, 95% CI 1.01 to 1.15; P < 0.001). However, no sex differences were observed in pooled results of populations with or without diabetes for all-cancer (RRR 1.02, 95% CI 0.98 to 1.06; P = 0.21), infectious (RRR 1.13, 95% CI 0.90 to 1.38; P = 0.33), and respiratory mortality (RRR 1.08, 95% CI 0.95 to 1.23; P = 0.26).

CONCLUSIONS

Compared with men with the same condition, women with diabetes have a 58% and 13% greater risk of CHD and all-cause mortality, respectively, although there was a significant heterogeneity between studies. This points to an urgent need to develop sex- and gender-specific risk assessment strategies and therapeutic interventions that target diabetes management in the context of CHD prevention.

Diabetes and kidney cancer survival in patients undergoing nephrectomy: A Canadian multi-center, propensity score analysis

INTRODUCTION

Diabetes has been associated with worse survival outcomes in various malignancies; however, there are conflicting data in kidney cancer. Determining whether diabetes is associated with survival in kidney cancer may help guide treatment in a comorbid patient population.

METHODS

We used the Canadian Kidney Cancer information system database to identify patients undergoing partial or radical nephrectomy between 1989 and 2017 for localized renal cell carcinoma at 16 institutions across Canada. We derived inverse probability of treatment weights (IPTW) from a propensity score model based on various clinical, surgical, and pathological characteristics. We used Cox proportional hazard models to evaluate the association between diabetes and cancer-specific and overall survival, in the sample weighted by the IPTW.

RESULTS

4828 patients met inclusion criteria, of whom 948 (19.6%) were diabetic. Median follow-up in those without death was 26.6 months (interquartile range 9.7-53.8). Among the entire cohort, 901 deaths were from any cause, and 299 deaths from kidney cancer. Before propensity score methods, diabetics were older, more likely to have comorbidities and clear cell histopathology. After propensity score adjustment, all characteristics were balanced between groups (standardized difference <0.10). IPTW-adjusted Cox proportional hazard models demonstrated no significant association between diabetes and cancer-specific (hazard ratio 1.13, 95% confidence interval 0.78-1.62), or overall survival (hazard ratio 1.14, 95% confidence interval 0.94-1.38).

CONCLUSIONS

Our multi-centre study found that diabetes and nondiabetics have similar survival following nephrectomy for kidney cancer.

Insulin and insulin-like growth factors act as renal cell cancer intratumoral regulators

The risk of renal cell carcinoma development is correlated with obesity and type II diabetes. Since insulin and insulin-like growth factors play a key role during development of both metabolic diseases, these molecules may be important in RCC pathophysiology We investigated the effect of insulin and IGFs on RCC cells using in vitro model with 786-O, 769-P, Caki-1, Caki-2, ACHN cancer cell lines. Cancer cells were compared with normal kidney cells - PCS-400-010 and HEK293. The growth, viability of cells as well as migration rate were assessed upon hormonal stimulation. The insulin receptor and Insulin-like growth factor 1 receptor presence were evaluated and the expression of 84 genes related to insulin signaling pathway. In all RCC cell lines IGF-1R expression was confirmed in contrast to IR, which was expressed only in control HEK293 cell line. Insulin and IGFs stimulated RCC cells growth and migration rate. Insulin, IGF-1 and IGF-2 triggered both IR and IGF-1R phosphorylation. Analyzed RCC did not secret insulin, IGF-1 or IGF-2 and were not activated in autocrine-paracrine signaling loop. Insulin and IGFs stimulations triggered down-regulation of PI3K-Akt-mTOR and Ras-MAPK pathway gens, as well as DOK2-3, INS, FRS3, IRS1-2, IGF1R - genes encoding insulin receptor-associated proteins. In conclusion, we showed that IGFs and insulin may play a stimulatory role for renal cancer cells, thus they can possibly affect renal cancer tumorigenesis and progression on cellular level.

Incidence and relative risk for developing cancers in women with gestational diabetes mellitus: a nationwide cohort study in Taiwan

OBJECTIVES

To evaluate the risk of developing cancers, particularly site-specific cancers, in women with gestational diabetes mellitus (GDM) in Taiwan.

SETTING

The National Health Insurance Research Database (NHIRD) of Taiwan.

PARTICIPANTS

This study was conducted using the nationwide data from 2000 to 2013. In total, 1 466 596 pregnant women with admission for delivery were identified. Subjects with GDM consisted of 47 373 women, while the non-exposed group consisted of 943 199 women without GDM. The participants were followed from the delivery date to the diagnosis of cancer, death, the last medical claim or the end of follow-up (31 December 2013), whichever came first.

PRIMARY OUTCOME MEASURES

Patients with a new diagnosis of cancer (International Classification of Diseases, ninth edition, with clinical modification (ICD-9-CM codes 140-208)) recorded in NHIRD were identified. The risk of 11 major cancer types was assessed, including cancers of head and neck, digestive organs, lung and bronchus, bone and connective tissue, skin, breast, genital organs, urinary system, brain, thyroid gland and haematological system.

RESULTS

The rates of developing cancers were significantly higher in women with GDM compared with the non-GDM group (2.24% vs 1.96%; p<0.001). After adjusting for maternal age at delivery and comorbidities, women with GDM had increased risk of cancers, including cancers of nasopharynx (adjusted HR, 1.739; 95 % CI, 1.400 to 2.161; p<0.0001), kidney (AHR, 2.169; 95 % CI, 1.428 to 3.293; p=0.0003), lung and bronchus (AHR, 1.372; 95 % CI, 1.044 to 1.803; p=0.0231), breast (AHR, 1.234; 95% CI, 1.093 to 1.393; p=0.007) and thyroid gland (AHR, 1.389; 95 % CI, 1.121 to 1.721; p=0.0026).

CONCLUSION

Women with GDM have a higher risk of developing cancers. Cancer screening is warranted in women with GDM. Future research should be aimed at establishing whether this association is causal.

Impact of diabetes mellitus on the prognostic value of the neutrophil-lymphocyte ratio in renal cell carcinoma

The aim of the present study was to evaluate the effect of diabetes mellitus (DM) on the neutrophil-lymphocyte ratio (NLR)-based prediction of the prognosis of patients with renal cell carcinoma (RCC). The data of 662 patients who had undergone nephrectomy for RCC between January 2004 and July 2014 were retrospectively reviewed. X-tile analysis was used to determine the optimal cutoff value for the NLR. Kaplan-Meier curves were drawn and the log-rank test was applied to determine the impact of the NLR (high vs. low) on the overall survival (OS) and metastasis-free survival (MFS). Univariate and multivariate Cox regression analyses were used to identify prognostic factors for OS and MFS. The median follow-up period after surgery was 50.35 months (range, 30.30–85.08 months). The optimal cutoff value of the NLR was determined to be 3.2 using X-tile software. In the analysis of total subjects, patients with a high NLR (≥3.2) had significantly worse OS and MFS rates than those with a low NLR (<3.2) (21.60% vs. 78.40%, P=0.001 for OS and 21.60% vs. 78.40%, P<0.0001 for MFS). In the non-DM subgroup, the OS and MFS rates of patients with a high NLR were significantly worse compared with those of patients with a low NLR (21.69% vs. 78.31%, P=0.003 for OS and 21.69% vs. 78.31%, P<0.001 for MFS). In the DM subgroup, although a high NLR was still associated with the MFS (NLR≥3.2, 21.43% vs. NLR<3.2, 78.57%; P=0.015), it was no longer associated with the OS (NLR≥3.2, 21.43% vs. NLR<3.2, 78.57%; P=0.192). Furthermore, multivariate analysis identified the NLR as a risk factor for OS and MFS in all patients [hazard ratio (HR)=1.77, 95% confidence interval (CI): 1.04–3.01, P=0.037; and HR=2.31, 95% CI: 1.45–3.70, P<0.001, respectively) and in the non-DM subgroup (HR=2.03, 95% CI: 1.05–3.93, P=0.036; and HR=2.57, 95% CI: 1.47–4.49, P=0.001, respectively), but not in the DM subgroup (P>0.05). In conclusion, DM is a factor that impairs the evaluation of the prognosis of RCC using NLR.

Epidemiology and Risk Factors for Kidney Cancer

The purpose of this narrative review is to summarize evidence of the epidemiology of and risk factors for kidney cancer with a focus on renal cell carcinoma in adults. The etiology of kidney cancer is largely unknown and the main epidemiologic determinants are large geographic and temporal variations in incidence rates. Established risk factors include tobacco smoking, body size, and history of hypertension and chronic kidney disease. Other suspected risk factors require additional investigation, as do the underlying biologic mechanisms that are responsible for disease occurrence. Opportunities to prevent kidney cancer include targeting modifiable risk factors-for example, smoking abstinence/cessation and body weight control-as well as interventions along the diagnostic pathway to improve early diagnosis. Molecular epidemiology, including, but not limited to, metabolomics and tumor genomics, are new areas of research that promise to play important roles in identifying some of the underlying causes of kidney cancer.

Cancer incidence among Finnish people with type 2 diabetes during 1989-2014

Diabetes and cancer are common diseases both with enormous impact on health burden globally. The increased risk of several types of cancer among people with type 2 diabetes mellitus has been indicated repeatedly. This study aimed at exploring and describing the association between type 2 diabetes and cancer incidence. A cohort of 428,326 people with type 2 diabetes was identified from the Finnish National Diabetes Register and followed up through a register linkage with the Finnish Cancer Registry for cancer incidence during 1988-2014. A total of 74,063 cases of cancer occurred in this cohort in 4.48 million person-years. This accounted for 16% more than the expected cancer incidence in the Finnish general population; the standardized incidence ratio (SIR) was 1.16 (95% confidence interval [CI] 1.15-1.16). There was a statistically significant excess of cancers of lip (SIR = 1.40, CI = 1.28-1.53), liver (SIR = 2.44, CI = 2.35-2.53), pancreas (SIR = 1.75, CI = 1.70-1.79), stomach (SIR = 1.22, CI = 1.18-1.26), colon (SIR = 1.22, CI = 1.19-1.25), gallbladder and bile ducts (SIR = 1.29, CI = 1.21-1.36), non-melanoma skin (SIR = 1.18, CI = 1.15-1.22), kidney (SIR = 1.42, CI = 1.37-1.47), bladder (SIR = 1.17, CI = 1.13-1.21), and thyroid (SIR = 1.22, CI = 1.12-1.31). There was a small statistically significant decrease in prostate cancer incidence (SIR = 0.95, CI = 0.93-0.96). This study showed an association between type 2 diabetes mellitus and the incidence of cancer at numerous sites in the Finnish population.

Challenges and perspectives in the treatment of diabetes associated breast cancer

Type 2 diabetes mellitus is one of the most common chronic disease worldwide and affects all cross-sections of the society including children, women, youth and adults. Scientific evidence has linked diabetes to higher incidence, accelerated progression and increased aggressiveness of different cancers. Among the different forms of cancer, research has reinforced a link between diabetes and the risk of breast cancer. Some studies have specifically linked diabetes to the highly aggressive, triple negative breast cancers (TNBCs) which do not respond to conventional hormonal/HER2 targeted interventions, have chances of early recurrence, metastasize, tend to be more invasive in nature and develop drug resistance. Commonly used anti-diabetic drugs, such as metformin, have recently gained importance in the treatment of breast cancer due to their proposed anti-cancer properties. Here we discuss the link between diabetes and breast cancer, the metabolic disturbances in diabetes that support the development of breast cancer, the challenges involved and future perspective and directions. We link the three main metabolic disturbances (dyslipidemia, hyperinsulinemia and hyperglycemia) that occur in diabetes to potential aberrant molecular pathways that may lead to the development of an oncogenic phenotype of the breast tissue, thereby leading to acceleration of cell growth, proliferation, migration, inflammation, angiogenesis, EMT and metastasis and inhibition of apoptosis in breast cancer cells. Furthermore, managing diabetes and treating cancer using a combination of anti-diabetic and classical anti-cancer drugs should prove to be more efficient in the treatment diabetes associated cancers.