Does cancer risk increase with HbA1c, independent of diabetes?

Extracellular matrix glycation and receptor for advanced glycation end-products activation: a missing piece in the puzzle of the association between diabetes and cancer

A growing body of epidemiologic evidence suggests that people with diabetes are at a significantly higher risk of many forms of cancer. However, the molecular mechanisms underlying this association are not fully understood. Cancer cells are surrounded by a complex milieu, also known as tumor microenvironment, which contributes to the development and metastasis of tumors. Of note, one of the major components of this niche is the extracellular matrix (ECM), which becomes highly disorganized during neoplastic progression, thereby stimulating cancer cell transformation, growth and spread. One of the consequences of chronic hyperglycemia, the most frequently observed sign of diabetes and the etiological source of diabetes complications, is the irreversible glycation and oxidation of proteins and lipids leading to the formation of the advanced glycation end-products (AGEs). These compounds may covalently crosslink and biochemically modify structure and functions of many proteins, and AGEs accumulation is particularly high in long-living proteins with low biological turnover, features that are shared by most, if not all, ECM proteins. AGEs-modified proteins are recognized by AGE-binding proteins, and thus glycated ECM components have the potential to trigger Receptor for advanced glycation end-products-dependent mechanisms. The biological consequence of receptor for advanced glycation end-products activation mechanisms seems to be connected, in different ways, to drive some hallmarks of cancer onset and tumor growth. The present review intends to highlight the potential impact of ECM glycation on tumor progression by triggering receptor for advanced glycation end-products-mediated mechanisms.

Fasting blood glucose, glycaemic control and prostate cancer risk in the Finnish Randomized Study of Screening for Prostate Cancer

Background

Diabetic men have lowered overall risk of prostate cancer (PCa), but the role of hyperglycaemia is unclear. In this cohort study, we estimated PCa risk among men with diabetic fasting blood glucose level.

Methods

Participants of the Finnish Randomized Study of Screening for Prostate Cancer (FinRSPC) were linked to laboratory database for information on glucose measurements since 1978. The data were available for 17,860 men. Based on the average yearly level, the men were categorised as normoglycaemic, prediabetic, or diabetic. Median follow-up was 14.7 years. Multivariable-adjusted Cox regression was used to calculate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for prostate cancer overall and separately by Gleason grade and metastatic stage.

Results

In total 1,663 PCa cases were diagnosed. Compared to normoglycaemic men, those men with diabetic blood glucose level had increased risk of PCa (HR 1.52; 95% CI 1.31–1.75). The risk increase was observed for all tumour grades, and persisted for a decade afterwards. Antidiabetic drug use removed the risk association. Limitations include absence of information on lifestyle factors and limited information on BMI.

Conclusions

Untreated diabetic fasting blood glucose level may be a prostate cancer risk factor.

Cancer risk among insulin users: comparing analogues with human insulin in the CARING five-country cohort study

AIMS/HYPOTHESIS

The aim of this work was to investigate the relationship between use of certain insulins and risk for cancer, when addressing the limitations and biases involved in previous studies.

METHODS

National Health Registries from Denmark (1996-2010), Finland (1996-2011), Norway (2005-2010) and Sweden (2007-2012) and the UK Clinical Practice Research Datalink database (1987-2013) were used to conduct a cohort study on new insulin users (N = 327,112). By using a common data model and semi-aggregate approach, we pooled individual-level records from five cohorts and applied Poisson regression models. For each of ten cancer sites studied, we estimated the rate ratios (RRs) by duration (≤0.5, 0.5-1, 1-2, 2-3, 3-4, 4-5, 5-6 and >6 years) of cumulative exposure to insulin glargine or insulin detemir relative to that of human insulin.

RESULTS

A total of 21,390 cancer cases occurred during a mean follow-up of 4.6 years. No trend with cumulative treatment time for insulin glargine relative to human insulin was observed in risk for any of the ten studied cancer types. Of the 136 associations tested in the main analysis, only a few increased and decreased risks were found: among women, a higher risk was observed for colorectal (RR 1.54, 95% CI 1.06, 2.25) and endometrial cancer (RR 1.78, 95% CI 1.07, 2.94) for ≤0.5 years of treatment and for malignant melanoma for 2-3 years (RR 1.92, 95% CI 1.02, 3.61) and 4-5 years (RR 3.55, 95% CI 1.68, 7.47]); among men, a lower risk was observed for pancreatic cancer for 2-3 years (RR 0.34, 95% CI 0.17, 0.66) and for liver cancer for 3-4 years (RR 0.36, 95% CI 0.14, 0.94) and >6 years (RR 0.22, 95% CI 0.05, 0.92). Comparisons of insulin detemir with human insulin also showed no consistent differences.

CONCLUSIONS/INTERPRETATION

The present multi-country study found no evidence of consistent differences in risk for ten cancers for insulin glargine or insulin detemir use compared with human insulin, at follow-up exceeding 5 years.

Psychological resources and glucoregulation in Japanese adults: Findings from MIDJA

OBJECTIVE

To examine associations between glucoregulation and 3 categories of psychological resources: hedonic well-being (i.e., life satisfaction, positive affect), eudaimonic well-being (i.e., personal growth, purpose in life, ikigai), and interdependent well-being (i.e., gratitude, peaceful disengagement, adjustment) among Japanese adults. The question is important given increases in rates of type 2 diabetes in Japan in recent years, combined with the fact that most prior studies linking psychological resources to better physical health have utilized Western samples.

METHOD

Data came from the Midlife in Japan Study involving randomly selected participants from the Tokyo metropolitan area, a subsample of whom completed biological data collection (N = 382; 56.0% female; M(SD)age = 55.5(14.0) years). Glycosylated hemoglobin (HbA1c) was the outcome. Models adjusted for age, gender, educational attainment, smoking, alcohol, chronic conditions, body mass index (BMI), use of antidiabetic medication, and negative affect.

RESULTS

Purpose in life (β = -.104, p = .021) was associated with lower HbA1c, and peaceful disengagement (β = .129, p = .003) was associated with higher HbA1c in fully adjusted models. Comparable to the effects of BMI, a 1 standard deviation change in well-being was associated with a .1% change in HbA1c.

CONCLUSIONS

Associations among psychological resources and glucoregulation were mixed. Healthy glucoregulation was evident among Japanese adults with higher levels of purpose in life and lower levels of peaceful disengagement, thereby extending prior research from the United States. The results emphasize the need for considering sociocultural contexts in which psychological resources are experienced in order to understand linkages to physical health. (PsycINFO Database Record

Insights into the relationships between diabetes, prediabetes, and cancer

Diabetes mellitus and cancer are two growing health problems. They have in common many modifiable risk factors including sex, age, obesity, physical activity, diet, alcohol, and smoking, and have a long latency before overtly manifesting. Patients with diabetes experience a roughly 20-25% higher cancer incidence compared to individuals without diabetes, and it depends on cancer site. Moreover, patients with diabetes who further develop cancer have increased early and late mortality in comparison with cancer patients without diabetes. Prediabetes and metabolic syndrome are also related to an increased risk of developing and die from cancer. Possible mechanisms linking diabetes and prediabetes with cancer include hyperglycemia (endogenous or exogenous), hyperinsulinemia, and alterations of insulin-like growth factor system, chronic subclinical inflammation, abnormalities in sex hormone metabolism, and adipokines. It becomes crucial to define the right orientation of the associations between diabetes and cancer in order to identify the modifiable pathogenic mechanisms. The common soil hypothesis claims that prediabetes and diabetes, as well as metabolic syndrome, may be considered a surrogate sign for dietary risk factors of cancer. The clepsydra of foods may help choose foods associated with healthy benefit while avoiding foods associated with harm, including cancer.

Association of Genomic Instability with HbA1c levels and Medication in Diabetic Patients

Diabetes Mellitus type 2 (DM2) is associated with increased cancer risk. Instability of the genetic material plays a key role in the aetiology of human cancer. This study aimed to analyse genomic instability with the micronucleus cytome assay in exfoliated buccal cells depending on glycated haemoglobin (HbA1c) levels and medication in 146 female DM2 patients. The occurrence of micronuclei was significantly increased in DM2 patients compared to healthy controls. Furthermore, it was doubled in DM2 patients with HbA1c > 7.5% compared to subjects with HbA1c ≤ 7.5%. Positive correlations were found between micronuclei frequencies and HbA1c as well as fasting plasma glucose. Patients under insulin treatment showed a two-fold increase in micronuclei frequencies compared to subjects under first-line medication (no drugs or monotherapy with non-insulin medication). However, after separation of HbA1c (cut-off 7.5%) only patients with severe DM2 characterised by high HbA1c and insulin treatment showed higher micronuclei frequencies but not patients with insulin treatment and low HbA1c. We demonstrated that the severity of DM2 accompanied by elevated micronuclei frequencies predict a possible enhanced cancer risk among female DM2 patients. Therapy, therefore, should focus on a strict HbA1c control and personalised medical treatments.

Caloric restriction - A promising anti-cancer approach: From molecular mechanisms to clinical trials

Cancer is the second leading cause of death worldwide and the morbidity is growing in developed countries. According to WHO, >14 million people per year are diagnosed with cancer and about 8 million die. Anti-cancer strategy includes chemo-, immune- and radiotherapy or their combination. Unfortunately, these widely used strategies often have insufficient efficacy and significant toxic effects on healthy cells. Consequently, the improvement of treatment approaches is an important goal. One of promising schemes to enhance the effect of therapy is the restriction of calorie intake or some nutrients. The combination of caloric restriction or its chemical mimetics along with anti-cancer drugs may suppress growth of tumor cells and enhance death of cancer cells. That will allow the dose of therapeutic drugs to be decreased and their toxic effects to be reduced. Here the possibility of using this combinatory therapy as well as the molecular mechanisms underlying this approach will be discussed.

Risk factors for cancer development in type 2 diabetes: A retrospective case-control study

BACKGROUND

The risk of several types of cancer is increased in type 2 diabetes mellitus. The earliest possible diagnosis of cancer - difficult within regular outpatient diabetes care - is of utmost importance for patients' survival. The aim of this multicenter, retrospective (years 1998-2015), case-control study was to identify risk factors associated with malignancy in subjects with diabetes treated in a typical outpatient setting.

METHODS

In the databases of 3 diabetic and 1 primary care clinics 203 patients (115 women) with type 2 diabetes mellitus who developed malignancy while treated for diabetes were identified. The control group consisted of 203 strictly age- and gender matched subjects with type 2 diabetes without cancer. Factors associated with diabetes: disease duration, antidiabetic medications use and metabolic control of diabetes were analyzed. Also other variables: BMI (body mass index), smoking habits, place of residence and comorbidities were included into analysis.

RESULTS

The most prevalent malignancies in men and women together were breast cancer (20.7 %) and colorectal cancer (16.3 %). HbA1c (hemoglobin A1c) level ≥8.5 %, obesity and insulin treatment in dose-dependent and time-varying manner demonstrated significant association with increased risk of malignancy, while metformin use was associated with a lower risk of cancer. Diabetes duration, comorbidities, smoking habits, place of residence and aspirin use did not show significant association with risk of malignancy.

CONCLUSIONS

In the outpatient setting the obese patients with poorly controlled insulin treated type 2 diabetes mellitus should be rigorously assessed towards malignancies, particularly breast cancer in women and colorectal cancer in men.

Diabetes and mortality in patients with prostate cancer: a meta-analysis

BACKGROUND

There are conflicting results as to the association between pre-existing diabetes and the risk of mortality in patients with prostate cancer. The purpose of this study is to estimate the influence of pre-existing diabetes on prostate cancer-specific mortality and all-cause mortality.

METHODS

We searched PubMed and Embase to identify studies that investigated the association between pre-existing diabetes and risk of death among men with prostate cancer. Pooled risk estimates and 95 % confidence intervals were calculated using fixed-effects models or random-effects models. Heterogeneity tests were conducted between studies. Publication bias was analyzed by using the Egger's test, Begg's test, and the trim and fill method.

RESULTS

Of the 733 articles identified, 17 cohort studies that had 274,677 male patients were included in this meta-analysis. Pre-existing diabetes was associated with a 29 % increase in prostate cancer-specific mortality [relative risk (RR) 1.29, 95 % CI 1.22-1.38, I(2) = 66.68 %], and with a 37 % increase in all-cause mortality (RR 1.37, 95 % CI 1.29-1.45, p < 0.01, I(2) = 90.26 %). Additionally, in a subgroup analysis that was a type specific analysis focusing on type 2 diabetes and was conducted only with three cohort studies, pre-existing type 2 diabetes was associated with all-cause mortality (RR 2.01, 95 % CI 1.37-2.96, I(2) = 95.55 %) and no significant association with prostate cancer-specific mortality was detected (RR 1.17, 95 % CI 0.96-1.42, I(2) = 75.59 %). There was significant heterogeneity between studies and no publication bias was found.

CONCLUSIONS

This meta-analysis suggests diabetes may result in a worse prognosis for men with prostate cancer. Considering heterogeneity between studies, additional studies should be conducted to confirm these findings, and to allow generalization regarding the influence that each type of diabetes has on prostate cancer mortality.

Prostate Cancer Patients With Unmanaged Diabetes or Receiving Insulin Experience Inferior Outcomes and Toxicities After Treatment With Radiation Therapy

BACKGROUND

The purpose of the study was to determine the effect of type 2 diabetes mellitus (T2DM) on outcomes and toxicities among men with localized prostate cancer receiving definitive radiation therapy.

PATIENTS AND METHODS

We performed a retrospective review of 3217 patients, from 1998 to 2013, subdivided into 5 subgroups: (I) no T2DM; (II) T2DM receiving oral antihyperglycemic agent that contains metformin, no insulin; (III) T2DM receiving nonmetformin oral agent alone, no insulin; (IV) T2DM receiving any insulin; and (V) T2DM not receiving medication. Outcome measures were overall survival, freedom from biochemical failure (BF), freedom from distant metastasis, cancer-specific survival, and toxicities. Kaplan-Meier analysis, log rank tests, Fine and Gray competing risk regression (to adjust for patient and lifestyle factors), Cox models, and subdistribution hazard ratios (sHRs) were used.

RESULTS

Of the 3217 patients, 1295 (40%) were low-risk, 1192 (37%) were intermediate-risk, and 652 (20%) were high risk. The group I to V distribution was 81%, 8%, 5%, 3%, and 4%. The median dose was 78 Gy, and the median follow-up time was 50 (range, 1-190) months. Group V had increased mortality (sHR, 2.1; 95% confidence interval [CI], 0.66-1.54), BF (sHR, 2.14; 0.88-1.83), and cause-specific mortality (sHR, 3.87; 95% CI, 1.31-11). Acute toxicities were higher in group IV versus group I (genitourinary: 38% vs. 26%; P = .01; gastrointestinal: 21% vs. 5%; P = 001). Late toxicities were higher in groups IV and V versus group I (12%-14% vs. 2%-6%; P < .01).

CONCLUSION

Men with T2DM not receiving medication and men with T2DM receiving insulin had worse outcomes and toxicities compared to other patients.

Oxidative Stress, DNA Damage and DNA Repair in Female Patients with Diabetes Mellitus Type 2

BACKGROUND

Diabetes mellitus type 2 (T2DM) is associated with oxidative stress which in turn can lead to DNA damage. The aim of the present study was to analyze oxidative stress, DNA damage and DNA repair in regard to hyperglycemic state and diabetes duration.

METHODS

Female T2DM patients (n = 146) were enrolled in the MIKRODIAB study and allocated in two groups regarding their glycated hemoglobin (HbA1c) level (HbA1c≤7.5%, n = 74; HbA1c>7.5%, n = 72). In addition, tertiles according to diabetes duration (DD) were created (DDI = 6.94±3.1 y, n = 49; DDII = 13.35±1.1 y, n = 48; DDIII = 22.90±7.3 y, n = 49). Oxidative stress parameters, including ferric reducing ability potential, malondialdehyde, oxidized and reduced glutathione, reduced thiols, oxidized LDL and F2-Isoprostane as well as the activity of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase were measured. Damage to DNA was analyzed in peripheral blood mononuclear cells and whole blood with single cell gel electrophoresis. DNA base excision repair capacity was tested with the modified comet repair assay. Additionally, mRNA expressions of nine genes related to base excision repair were analyzed in a subset of 46 matched individuals.

RESULTS

No significant differences in oxidative stress parameters, antioxidant enzyme activities, damage to DNA and base excision repair capacity, neither between a HbA1c cut off />7.5%, nor between diabetes duration was found. A significant up-regulation in mRNA expression was found for APEX1, LIG3 and XRCC1 in patients with >7.5% HbA1c. Additionally, we observed higher total cholesterol, LDL-cholesterol, LDL/HDL-cholesterol, triglycerides, Framingham risk score, systolic blood pressure, BMI and lower HDL-cholesterol in the hyperglycemic group.

CONCLUSION

BMI, blood pressure and blood lipid status were worse in hyperglycemic individuals. However, no major disparities regarding oxidative stress, damage to DNA and DNA repair were present which might be due to good medical treatment with regular health checks in T2DM patients in Austria.

Diabetes Mellitus Type 2: A Driving Force for Urological Complications

Type 2 diabetes mellitus (T2DM) is a growing epidemic associated with many adverse complications. Urological complications of diabetes mellitus in men are gaining recognition. Previously unknown associations between T2DM and risk for prostate cancer, bladder cancer, renal cell carcinomas, urinary tract infections, nephrolithiasis, penile lesions, androgen deficiency, and erectile dysfunction have been discovered. Significantly, metformin could play a role in the management of urological malignancies, and therapies used for management of these cancers could in return lead to increased risk for diabetes. In this review, we aim to bridge the gap between T2DM and urological complications by discussing the latest findings in these fields, with the ultimate goal being improved patient care on both fronts.

Cancer incidence in persons with type 1 diabetes: a five-country study of 9,000 cancers in type 1 diabetic individuals

AIMS/HYPOTHESIS

An excess cancer incidence of 20-25% has been identified among persons with diabetes, most of whom have type 2 diabetes. We aimed to describe the association between type 1 diabetes and cancer incidence.

METHODS

Persons with type 1 diabetes were identified from five nationwide diabetes registers: Australia (2000-2008), Denmark (1995-2014), Finland (1972-2012), Scotland (1995-2012) and Sweden (1987-2012). Linkage to national cancer registries provided the numbers of incident cancers in people with type 1 diabetes and in the general population. We used Poisson models with adjustment for age and date of follow up to estimate hazard ratios for total and site-specific cancers.

RESULTS

A total of 9,149 cancers occurred among persons with type 1 diabetes in 3.9 million person-years. The median age at cancer diagnosis was 51.1 years (interquartile range 43.5-59.5). The hazard ratios (HRs) (95% CIs) associated with type 1 diabetes for all cancers combined were 1.01 (0.98, 1.04) among men and 1.07 (1.04, 1.10) among women. HRs were increased for cancer of the stomach (men, HR 1.23 [1.04, 1.46]; women, HR 1.78 [1.49, 2.13]), liver (men, HR 2.00 [1.67, 2.40]; women, HR 1.55 [1.14, 2.10]), pancreas (men, HR 1.53 [1.30, 1.79]; women, HR 1.25 [1.02,1.53]), endometrium (HR 1.42 [1.27, 1.58]) and kidney (men, HR 1.30 [1.12, 1.49]; women, HR 1.47 [1.23, 1.77]). Reduced HRs were found for cancer of the prostate (HR 0.56 [0.51, 0.61]) and breast (HR 0.90 [0.85, 0.94]). HRs declined with increasing diabetes duration.

CONCLUSION

Type 1 diabetes was associated with differences in the risk of several common cancers; the strength of these associations varied with the duration of diabetes.

Baseline glycemic status and mortality in 241,499 Korean metropolitan subjects: A Kangbuk Samsung Health Study

OBJECTIVE

Diabetes and prediabetes subjects have increased risk for mortality. We analyzed the mortality risk due to all causes, cardiovascular disease (CVD) and cancer in Korean subjects participating in a health-screening program according to baseline glycemic status and HbA1c levels.

MATERIALS/METHODS

Among 241,499 participants of a health-screening program between 2005 and 2012, the risk of death from all causes, CVD, and cancer was calculated based on the baseline glycemic status (normoglycemia, prediabetes, and diabetes) and HbA1c levels. Uncontrolled diabetes was defined as HbA1c≥7.0%. Vital status and confirmation of the cause of death were based on the analysis of death certificate records from the National Death Index.

RESULTS

During 923,343.1 person-years of follow-up, 877 participants died. The multivariable-adjusted hazard ratios (HR) of subjects with controlled and uncontrolled diabetes to normoglycemic subjects for all-cause mortality were 1.58 (95% CI 1.24-2.03) and 2.26 (95% CI 1.78-2.86), respectively. The HRs of subjects with controlled and uncontrolled diabetes to normoglycemic subjects for mortality due to cancer were 1.75 (95% CI 1.23-2.48) and 1.67 (95% CI 1.13-2.45). However, glycemic status was not significantly associated with the risk of mortality due to CVD. The subjects with HbA1c higher than 6.5% showed more than 2-fold increased risk for all-cause mortality and the subjects with HbA1c lower than 5.2% showed increased HR (1.45, 95% CI 1.06-1.97) compared with those with HbA1c of 5.5% in subjects not taking anti-diabetic medications.

CONCLUSIONS

Mortality risk from all causes and cancer significantly increased in diabetes subjects regardless of the glucose control status. In subjects not taking anti-diabetic medications, both high and low HbA1c resulted in increased risk for all-cause mortality.

Type 2 diabetes mellitus and risk of gallbladder cancer: a systematic review and meta-analysis of observational studies

AIMS

Increasing evidence suggests that a history of type 2 diabetes mellitus (type 2 DM) may be involved in the development of various sites of cancer. However, the association with risk of gallbladder cancer remains unclear.

METHODS

We identified studies by a literature search of MEDLINE and EMBASE through 31 August 2014 and by searching the reference lists of pertinent articles. All data were independently extracted by two investigators using a standardized data abstraction tool. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were calculated with a random effects model.

RESULTS

A total of 20 studies (eight case-control studies and 12 cohort studies) were included in this meta-analysis. Analysis of these 20 studies found that compared with non-diabetic individuals, diabetic individuals had an increased risk of gallbladder cancer (SRR = 1.56, 95% CI: 1.36-1.79). There was evidence of moderate heterogeneity among these studies (p = 0.010 and I(2)  = 43.5%). This increased risk relationship is independent of smoking, body mass index and a history of gallstones. However, whether or not controlled for, alcohol use may be one of the potential confounders that significantly affect the association between type 2 DM and the risk of gallbladder cancer. Diabetic women and men had a similarly increased risk of gallbladder cancer associated with type 2 DM.

CONCLUSIONS

These findings of this systematic review indicate that compared with non-diabetic individuals, both men and women with type 2 DM had an increased risk of gallbladder cancer. Copyright © 2015 John Wiley & Sons, Ltd.

High hemoglobin A1c levels within the non-diabetic range are associated with the risk of all cancers

Previous studies have reported associations between diabetes and cancer risk. However, specific association of hemoglobin A1c (HbA1c) levels with cancer risk remains inconclusive. We followed 29,629 individuals (11,336 men; 18,293 women) aged 46-80 years who participated in the Japan Public Health Center-based prospective study who had HbA1c measurements available and were cancer-free at baseline. Cancer incidence was assessed by systemic surveys. We estimated hazard ratios (HRs) for cancer risk with adjustment for age sex, geographic area, body mass index, smoking status, physical activity, alcohol, coffee, vegetable and total energy consumption, and history of cardiovascular disease. After a median follow-up of 8.5 years, 1,955 individuals had developed cancer. Higher HbA1c levels within both the non-diabetic and diabetic ranges in individuals without known diabetes were associated with overall cancer risk. Compared with individuals without known diabetes and HbA1c levels of 5.0-5.4%, the HRs for all cancers were 1.27 (95% confidence interval, 1.07-1.52); 1.01 (0.90-1.14); 1.28 (1.09-1.49); and 1.43 (1.14-1.80) for individuals without known diabetes and HbA1c levels <5.0%, 5.5-5.9%, 6.0-6.4%, and ≥6.5%, respectively, and 1.23 (1.02-1.47) for individuals with known diabetes. The lowest HbA1c group had the highest risk of liver cancer, and HbA1c levels were linearly associated with the risk of all cancers after excluding liver cancer (P for linear trend, 0.004). In conclusion, our findings corroborate the notion that glycemic control in individuals with high HbA1c levels may be important not only to prevent diabetes but also to prevent cancer.

Effects of metformin on clinical outcome in diabetic patients with advanced HCC receiving sorafenib

BACKGROUND AND OBJECTIVE

Several studies have reported an association between type 2 diabetes mellitus and hepatocellular carcinoma (HCC). Data from several retrospective studies and meta-analyses have highlighted a reduction of about 50% in the risk of developing HCC in cirrhotic patients treated with metformin for diabetes. The aim of this study was to evaluate the different outcomes of patients who received or did not receive metformin during treatment with sorafenib.

METHODS

We analyzed 93 patients consecutively treated with sorafenib. Forty-two (45.2%) patients were diabetic, of whom 31 were on metformin. Progression-free survival (PFS) and overall survival (OS) were estimated with the Kaplan-Meier method and compared with the log-rank test.

RESULTS

The concomitant use of sorafenib and metformin was associated with a median PFS of 2.6 months (95% CI 1.9-3.3) compared to 5.0 months (95% CI 2.5-8.2) for patients receiving sorafenib alone (p = 0.029). The median OS of patients treated with the combination was 10.4 months (95% CI 3.9-14.4) compared to 15.1 months (95% CI 11.7-17.8) for those who were not given metformin (p = 0.014).

CONCLUSIONS

Our findings could be the result of increased tumor aggressiveness and resistance to sorafenib in metformin-treated patients.

Obesity and Diabetes: The Increased Risk of Cancer and Cancer-Related Mortality

Obesity and type 2 diabetes are becoming increasingly prevalent worldwide, and both are associated with an increased incidence and mortality from many cancers. The metabolic abnormalities associated with type 2 diabetes develop many years before the onset of diabetes and, therefore, may be contributing to cancer risk before individuals are aware that they are at risk. Multiple factors potentially contribute to the progression of cancer in obesity and type 2 diabetes, including hyperinsulinemia and insulin-like growth factor I, hyperglycemia, dyslipidemia, adipokines and cytokines, and the gut microbiome. These metabolic changes may contribute directly or indirectly to cancer progression. Intentional weight loss may protect against cancer development, and therapies for diabetes may prove to be effective adjuvant agents in reducing cancer progression. In this review we discuss the current epidemiology, basic science, and clinical data that link obesity, diabetes, and cancer and how treating obesity and type 2 diabetes could also reduce cancer risk and improve outcomes.

Prolonged Nightly Fasting and Breast Cancer Risk: Findings from NHANES (2009-2010)

BACKGROUND

A novel line of research has emerged, suggesting that daily feeding-fasting schedules that are synchronized with sleep-wake cycles have metabolic implications that are highly relevant to breast cancer. We examined associations of nighttime fasting duration with biomarkers of breast cancer risk among women in the 2009-2010 U.S. National Health and Nutrition Examination Survey.

METHODS

Dietary, anthropometric, and HbA1c data were available for 2,212 women, and 2-hour postprandial glucose concentrations were available for 1,066 women. Nighttime fasting duration was calculated using 24-hour food records. Separate linear regression models examined associations of nighttime fasting with HbA1c and 2-hour glucose concentrations. Logistic regression modeled associations of nighttime fasting with elevated HbA1c (HbA1c ≥ 39 mmol/mol or 5.7%) and elevated 2-hour glucose (glucose ≥ 140 mg/dL). All models adjusted for age, education, race/ethnicity, body mass index, total kcal intake, evening kcal intake, and the number of eating episodes per day.

RESULTS

Each 3-hour increase in nighttime fasting (roughly 1 SD) was associated with a 4% lower 2-hour glucose measurement [β, 0.96; 95% confidence interval (CI), 0.93-1.00; P < 0.05], and a nonstatistically significant decrease in HbA1c. Logistic regression models indicate that each 3-hour increase in nighttime fasting duration was associated with roughly a 20% reduced odds of elevated HbA1c (OR, 0.81; 95% CI, 0.68-0.97; P < 0.05) and nonsignificantly reduced odds of elevated 2-hour glucose.

CONCLUSIONS

A longer nighttime duration was significantly associated with improved glycemic regulation.

IMPACT

Randomized trials are needed to confirm whether prolonged nighttime fasting could improve biomarkers of glucose control, thereby reducing breast cancer risk.

Impaired glucose metabolism among those with and without diagnosed diabetes and mortality: a cohort study using Health Survey for England data

BACKGROUND

The extent that controlled diabetes impacts upon mortality, compared with uncontrolled diabetes, and how pre-diabetes alters mortality risk remain issues requiring clarification.

METHODS

We carried out a cohort study of 22,106 Health Survey for England participants with a HbA1C measurement linked with UK mortality records. We estimated hazard ratios (HRs) of all-cause, cancer and cardiovascular disease (CVD) mortality and 95% confidence intervals (CI) using Cox regression.

RESULTS

Average follow-up time was seven years and there were 1,509 deaths within the sample. Compared with the non-diabetic and normoglycaemic group (HbA1C <5.7% [<39 mmol/mol] and did not indicate diabetes), undiagnosed diabetes (HbA1C ≥6.5% [≥48 mmol/mol] and did not indicate diabetes) inferred an increased risk of mortality for all-causes (HR 1.40, 1.09-1.80) and CVD (1.99, 1.35-2.94), as did uncontrolled diabetes (diagnosed diabetes and HbA1C ≥6.5% [≥48 mmol/mol]) and diabetes with moderately raised HbA1C (diagnosed diabetes and HbA1C 5.7-<6.5% [39-<48 mmol/mol]). Those with controlled diabetes (diagnosed diabetes and HbA<5.7% [<39 mmol/mol]) had an increased HR in relation to mortality from CVD only. Pre-diabetes (those who did not indicate diagnosed diabetes and HbA1C 5.7-<6.5% [39-<48 mmol/mol]) was not associated with increased mortality, and raised HbA1C did not appear to have a statistically significant impact upon cancer mortality. Adjustment for BMI and socioeconomic status had a limited impact upon our results. We also found women had a higher all-cause and CVD mortality risk compared with men.

CONCLUSIONS

We found higher rates of all-cause and CVD mortality among those with raised HbA1C, but not for those with pre-diabetes, compared with those without diabetes. This excess differed by sex and diabetes status. The large number of deaths from cancer and CVD globally suggests that controlling blood glucose levels and policies to prevent hyperglycaemia should be considered public health priorities.

Hyperglycemia and chronic liver diseases on risk of hepatocellular carcinoma in Chinese patients with type 2 diabetes--National cohort of Taiwan Diabetes Study

This study examined whether glycated hemoglobin A1C (HbA1C) and chronic liver diseases are associated with hepatocellular carcinoma (HCC) risk in Type 2 diabetic patients. A retrospective cohort study consisting of 51,705 patients with Type 2 diabetes aged 30 and over enrolled in the National Diabetes Care Management Program before 2004 was used in Cox proportional hazards models. HbA1C was independently associated with HCC incidence, and multivariate-adjusted hazard ratio (HR) of HCC was 1.20 (95% confidence interval, CI: 1.02-1.41) for patients with a level of HbA1c ≥ 9% compared with patients with a level of HbA1c <7% after multivariate adjustment. We observed a significant linear trend in HCC incidence with increasing HbA1c (p for trend = 0.02, HR = 1.07, 95% CI = 1.01-1.12 for every 1% increment in HbA1c). We observed significant HRs of HCC for patients with a level of HbA1c ≥ 9% with alcoholic liver damage, liver cirrhosis, HBV, HCV and any one of chronic liver diseases compared with patients with a level of HbA1c <9% and no counterpart comorbidity in the entire sample (HR = 8.63, 95% CI = 1.41-52.68; HR = 5.02, 95% CI = 3.10-8.12; HR = 2.53, 95% CI = 1.10-5.85; HR = 1.79, 95% CI = 1.01-3.17; and HR = 3.59, 95% CI = 2.56-5.02, respectively). Our results suggest significant joint associations of HbA1c ≥ 9% and chronic liver diseases. Lifestyle or treatment interventions such as maintaining a satisfactory glycemic control and chronic liver diseases may reduce the burden of HCC.

Diabetes mellitus and ovarian cancer: more complex than just increasing risk

OBJECTIVE

Diabetes mellitus (DM) is a risk factor for endometrial cancer and is associated with poorer outcomes in breast and colon cancers. This association is less clear in epithelial ovarian cancer (EOC). We sought to examine the effect of DM on progression-free (PFS) and overall survival (OS) in women with EOC.

METHODS

A retrospective cohort study of EOC patients diagnosed between 2004 and 2009 at a single institution was performed. Demographic, pathologic and DM diagnosis data were abstracted. Pearson chi-square test and t test were used to compare variables. The Kaplan-Meier method and the log rank test were used to compare PFS and OS between non-diabetic (ND) and DM patients.

RESULTS

62 (17%) of 367 patients had a diagnosis of DM. No differences in age, histology, debulking status, or administration of intraperitoneal chemotherapy between ND and DM patients were present, although there were more stage I and IV patients in the ND group (p=0.04). BMI was significantly different between the two groups (ND vs. DM, 27.5 vs. 30.7kg/m(2), p<0.001). While there were no differences in survival based on BMI, diabetic patients had a poorer PFS (10.3 vs. 16.3months, p=0.024) and OS (26.1 vs. 42.2months, p=0.005) compared to ND patients. Metformin use among diabetic patients did not appear to affect PFS or OS.

CONCLUSIONS

EOC patients with DM have poorer survival than patients without diabetes; this association is independent of obesity. Metformin use did not affect outcomes. The pathophysiology of this observation requires more inquiry.

Poor glycemic control of diabetes mellitus is associated with higher risk of prostate cancer detection in a biopsy population

OBJECTIVES

To evaluate the impact of glycemic control of diabetes mellitus (DM) on prostate cancer detection in a biopsy population.

PATIENTS AND METHODS

We retrospectively reviewed the records of 1,368 men who underwent prostate biopsy at our institution. We divided our biopsy population into three groups according to their history of DM, and their Hemoglobin A1c (HbA1c) level: a no-DM (DM-) group; a good glycemic control (DM+GC) group (HbA1c <6.5%); and a poor glycemic control (DM+PC) group (HbA1c ≥6.5%). For sub-analyses, the DM+PC group was divided into a moderately poor glycemic control (DM+mPC) group (6.5≤ HbA1c <7.5%) and a severely poor glycemic control (DM+sPC) group (HbA1c ≥7.5%).

RESULTS

Among 1,368 men, 338 (24.7%) had a history of DM, and 393 (28.7%) had a positive biopsy. There was a significant difference in prostatic specific antigen density (PSAD) (P = 0.037) and the frequency of abnormal DRE findings (P = 0.031) among three groups. The occurrence rate of overall prostate cancer (P<0.001) and high-grade prostate cancer (P = 0.016) also presented with a significantly difference. In the multivariate analysis, the DM+PC group was significantly associated with a higher rate of overall prostate cancer detection in biopsy subjects compared to the DM- group (OR = 2.313, P = 0.001) but the DM+PC group was not associated with a higher rate of high-grade (Gleason score ≥7) diseases detected during the biopsy (OR = 1.297, P = 0.376). However, in subgroup analysis, DM+sPC group was significantly related to a higher risk of high-grade diseases compared to the DM- group (OR = 2.446, P = 0.048).

CONCLUSIONS

Poor glycemic control of DM was associated with a higher risk of prostate cancer detection, including high-grade disease, in the biopsy population.