Concentrations of IGF-I and IGFBP-3 and brain tumor risk in the European Prospective Investigation into Cancer and Nutrition

Skin advanced glycation end-products as indicators of the metabolic profile in diabetes mellitus: correlations with glycemic control, liver phenotypes and metabolic biomarkers

INTRODUCTION

The production of advanced glycation end-products (AGEs) is a key pathomechanism related to the complications of diabetes mellitus. The measurement of HbA1c as one of the AGEs is widely used in the clinic, but also other proteins undergo glycation in the course of diabetes. Here, we measure skin AGEs (SAGEs) in patients with diabetes type 1 (DM1) and type 2 (DM2) and correlate them with metabolic markers as well as non-invasively measured liver fibrosis and steatosis.

PATIENTS AND METHODS

In this cross-sectional study, a total of 64 patients with either DM1 or DM2 and 28 healthy controls were recruited. SAGEs were measured using autofluorescence (AGE Reader). Liver fibrosis and steatosis were quantified using transient elastography, which determines liver stiffness measurement (LSM) and controlled attenuation parameter (CAP). FGF19, FGF21 and GDF-15 were measured in blood samples using ELISA.

RESULTS

SAGEs were elevated in both groups of patients with diabetes as compared to healthy controls (both p < 0.001) and were higher in patients with DM2 in comparison to DM1 (p = 0.006). SAGEs correlated positively with HbA1c (r = 0.404, p < 0.001), CAP (r = 0.260, p = 0.016) and LSM (r = 0.356, p < 0.001), and negatively with insulin growth factor binding protein 3 (p < 0.001). We also detected a positive correlation between GDF15 and SAGEs (r = 0.469, p < 0.001).

CONCLUSIONS

SAGEs are significantly elevated in patients with both DM types 1 and 2 and correlate with metabolic markers, including HbA1c and GDF15. They might also help to detect patients with advanced liver injury in the setting of diabetes.

Safety of long-term use of daily and long-acting growth hormone in growth hormone-deficient adults on cancer risk

Daily injections of recombinant human growth hormone (rhGH) have been used in clinical practice for almost four decades as a replacement therapy in adult patients with GH deficiency (GHD). Long-term adherence to daily injections of rhGH is a clinical concern that may result in reduced therapeutic efficacy, and long-acting GH (LAGH) formulations have been developed in an attempt of overcoming this problem. Long-term safety issues of rhGH are the other side of the coin that has been carefully monitored over the years, particularly related to the proliferative actions of GH that could increase the risk of tumor recurrence or induce the development of new benign and malignant tumors. In this review, we present what is currently known about the cancer risk in GHD adults treated with daily rhGH injections and we discuss the major concerns and responses needed from future surveillance studies regarding the safety of LAGH preparations.

Elevated IGF-1 concentrations in children with low grade glioma: A descriptive analysis in a retrospective national cohort

Children with low grade glioma (LGG) may present with, or develop, elevated concentrations of insulin-like growth factor 1 (IGF-1). The prevalence, pathophysiology, or its possible clinical effects are poorly understood. Our aim was to evaluate the prevalence of such elevated IGF-1 concentrations and to describe its association with linear growth, body mass index (BMI), pituitary outcome, and tumor behavior in a large retrospective national cohort. From a nationwide retrospective cohort of pediatric brain tumor survivors diagnosed between 2002 and 2012, tumor, treatment, endocrine, and auxological data of children with LGG were collected (n = 358). Prevalence and risk factors for elevated IGF-1 concentrations, as well as the association between having elevated IGF-1 concentrations and receiving tumor treatment, were explored. IGF-1 concentrations had only been measured in 45.5% of cases (n = 163/358). In 18.4% of 163 children with available IGF-1 measurements, IGF-1 concentrations were found elevated. No association was described between having an elevated IGF-1 concentration and tumor behavior or height SDS at last moment of follow-up. Multivariate logistic regression identified posterior pituitary disorder (OR 6.14 95% CI: 2.21-17.09) and BMI SDS at follow-up (OR 1.56 95% CI: 1.09-2.20) to be significantly associated with elevated IGF-1 concentrations. In this retrospective cohort of children with LGG, IGF-1 was found elevated in 18.4% of children with available IGF-1 measurements. Elevated IGF-1 seems to be related to hypothalamic dysfunction worsening over time. Larger prospective cohort studies are needed.

Pre-diagnostic blood biomarkers for adult glioma

Glioma is one of the most common malignant primary brain tumours in adults, of which, glioblastoma is the most prevalent and malignant entity. Glioma is often diagnosed at a later stage of disease progression, which means it is associated with significant mortality and morbidity. Therefore, there is a need for earlier diagnosis of these tumours, which would require sensitive and specific biomarkers. These biomarkers could better predict glioma onset to improve diagnosis and therapeutic options for patients. While liquid biopsies could provide a cheap and non-invasive test to improve the earlier detection of glioma, there is little known on pre-diagnostic biomarkers which predate disease detection. In this review, we examine the evidence in the literature for pre-diagnostic biomarkers in glioma, including metabolomics and proteomics. We also consider the limitations of these approaches and future research directions of pre-diagnostic biomarkers for glioma.

Prediagnostic biomarkers for early detection of glioma—using case–control studies from cohorts as study approach

Background

Understanding the trajectory and development of disease is important and the knowledge can be used to find novel targets for therapy and new diagnostic tools for early diagnosis.

Methods

Large cohorts from different parts of the world are unique assets for research as they have systematically collected plasma and DNA over long-time periods in healthy individuals, sometimes even with repeated samples. Over time, the population in the cohort are diagnosed with many different diseases, including brain tumors.

Results

Recent studies have detected genetic variants that are associated with increased risk of glioblastoma and lower grade gliomas specifically. The impact for genetic markers to predict disease in a healthy population has been deemed low, and a relevant question is if the genetic variants for glioma are associated with risk of disease or partly consist of genes associated to survival. Both metabolite and protein spectra are currently being explored for early detection of cancer.

Conclusions

We here present a focused review of studies of genetic variants, metabolomics, and proteomics studied in prediagnostic glioma samples and discuss their potential in early diagnostics.

Safety of growth hormone (GH) treatment in GH deficient children and adults treated for cancer and non-malignant intracranial tumors-a review of research and clinical practice

Individuals surviving cancer and brain tumors may experience growth hormone (GH) deficiency as a result of tumor growth, surgical resection and/or radiotherapy involving the hypothalamic-pituitary region. Given the pro-mitogenic and anti-apoptotic properties of GH and insulin-like growth factor-I, the safety of GH replacement in this population has raised hypothetical safety concerns that have been debated for decades. Data from multicenter studies with extended follow-up have generally not found significant associations between GH replacement and cancer recurrence or mortality from cancer among childhood cancer survivors. Potential associations with secondary neoplasms, especially solid tumors, have been reported, although this risk appears to decline with longer follow-up. Data from survivors of pediatric or adult cancers who are treated with GH during adulthood are scarce, and the risk versus benefit profile of GH replacement of this population remains unclear. Studies pertaining to the safety of GH replacement in individuals treated for nonmalignant brain tumors, including craniopharyngioma and non-functioning pituitary adenoma, have generally been reassuring with regards to the risk of tumor recurrence. The present review offers a summary of the most current medical literature regarding GH treatment of patients who have survived cancer and brain tumors, with the emphasis on areas where active research is required and where consensus on clinical practice is lacking.

The relationship between rice consumption and glioma: a case-control study in adults

Previous studies have shown the effect of refined grains on various cancers; however, data on the link between rice consumption and brain cancer are scarce. We aimed to investigate the relationship between rice consumption and glioma in Iranian adults. Current hospital-based case–control study was done in Tehran between 2009 and 2011. Cases were individuals with pathologically confirmed glioma in a maximally 1 month of the disease diagnosis (n = 128). Controls were individuals, aged between 20 and 75 years, who were hospitalized or were outpatients referred to other wards of the same hospital (n = 256). Cases and controls were frequently matched in terms of age and gender. Usual dietary intakes of participants, including rice consumption, during the preceding year were examined using a Block-format validated semi-quantitative 126-item food frequency questionnaire. Compared with participants in the lowest tertile of rice consumption (< 181 g/day), those in the highest tertile (≥ 279 g/day) had 2.47 times greater chance for having glioma (OR: 2.47, 95% CI 1.44–4.23). This relationship was also seen when potential confounders including demographic variables, energy and dietary intakes as well as body mass index were taking into account; such that individuals in the top tertile of rice consumption had 2.46 times greater odds of glioma compared with those in the bottom tertile (OR: 2.46, 95% CI 1.01–5.97). We found that rice consumption was positively associated with risk of glioma in adults. Further prospective studies are required to confirm this finding.

Endurance Exercise Mitigates Immunometabolic Adipose Tissue Disturbances in Cancer and Obesity

Adipose tissue is considered an endocrine organ whose complex biology can be explained by the diversity of cell types that compose this tissue. The immune cells found in the stromal portion of adipose tissue play an important role on the modulation of inflammation by adipocytokines secretion. The interactions between metabolic active tissues and immune cells, called immunometabolism, is an important field for discovering new pathways and approaches to treat immunometabolic diseases, such as obesity and cancer. Moreover, physical exercise is widely known as a tool for prevention and adjuvant treatment on metabolic diseases. More specifically, aerobic exercise training is able to increase the energy expenditure, reduce the nutrition overload and modify the profile of adipocytokines and myokines with paracrine and endocrine effects. Therefore, our aim in this review was to cover the effects of aerobic exercise training on the immunometabolism of adipose tissue in obesity and cancer, focusing on the exercise-related modification on adipose tissue or immune cells isolated as well as their interaction.

miR-4286 is Involved in Connections Between IGF-1 and TGF-β Signaling for the Mesenchymal Transition and Invasion by Glioblastomas

The insulin-like growth factor (IGF)-1 and transforming growth factor (TGF)-β signal pathways are both recognized as important in regulating cancer prognosis, such as the epithelial-to-mesenchymal transition (EMT) and cell invasion. However, cross-talk between these two signal pathways in glioblastoma multiforme (GBM) is still unclear. In the present study, by analyzing data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GSE) 4412, GBM patients with higher IGF-1 levels exhibited poorer survival. Genes positively correlated with IGF-1 were enriched in EMT and TGF-β signal pathways. IGF-1 treatment enhanced mesenchymal marker expressions and GBM cell invasion. A significant positive correlation was observed for IGF-1 with TGF-β1 (TGFB1) or TGF-β receptor 2 (TGFBR2), both of which participate in TGF-β signaling and are risk genes in the GBM process. IGF-1 stimulation promoted both TGFB1 and TGFBR2 expressions. LY2157299, a TGF-β signaling inhibitor, attenuated IGF-1-enhanced GBM cell invasion and mesenchymal transition. By analyzing IGF-1-regulated microRNA (miR) profiles, miR-4286 was found to be significantly downregulated in IGF-1-treated cells and could be targeted to both TGFB1 and TGFBR2. Overexpression of miR-4286 significantly attenuated expressions of the IGF-1-mediated mesenchymal markers, TGFB1 and TGFBR2. Using kinase inhibitors, only U0126 treatment showed an inhibitory effect on IGF-1-reduced miR-4286 and IGF-1-induced TGFB1/TGFBR2 expressions, suggesting that MEK/ERK signaling is involved in the IGF-1/miR-4286/TGF-β signaling axis. Finally, our results suggested that miR-4286 might act as a tumor suppressive microRNA in inhibiting IGF-1-enhanced GBM cell invasion. In conclusion, IGF-1 is connected to TGF-β signaling in regulating the mesenchymal transition and cell invasion of GBM through inhibition of miR-4286. Our findings provide new directions and mechanisms for exploring GBM progression.

Circulating Insulin-like Growth Factor-I Concentrations and Risk of 30 Cancers: Prospective Analyses in UK Biobank

Circulating insulin-like growth factor I (IGF-I) is positively associated with the risks of colorectal, breast, and prostate cancer, but evidence for other less common cancers is limited. In this study, we investigated associations between serum IGF-I concentrations and incidence of less common cancers in the UK Biobank study. To enable comparison of effect estimates, and as positive controls, both common and less common cancer sites (total 30) were included in an outcome-wide analysis. Data from 394,388 cancer-free participants in the UK Biobank study were analyzed. Multivariable adjusted Cox proportional hazards models were used to determine associations between baseline serum IGF-I concentrations and cancer incidence, using repeated IGF-I measurements from up to 14,149 participants to correct for regression dilution bias. Higher IGF-I concentration was associated with increased risks of thyroid cancer [HR per 5 nmol/L higher concentration 1.18; 95% confidence interval (CI), 1.01-1.37] in addition to colorectal (HR, 1.08; 95% CI, 1.03-1.13), breast (HR, 1.11; 95% CI, 1.07-1.15), and prostate cancer (HR, 1.08; 95% CI, 1.05-1.12), and reduced risks of ovarian and liver cancer. Mean follow-up was 6.9 years and the possibility that the observed associations may be influenced by reverse causality bias cannot be excluded. Additional nominally significant associations with malignant melanoma, multiple myeloma, oral cancer, and esophageal squamous cell carcinoma did not survive correction for multiple testing. Studies with longer follow-up and pooled analyses are needed to further assess how broad the role of IGF-I is in cancer development. SIGNIFICANCE: The results from this outcome-wide analysis are consistent with a positive association of IGF-I with cancers at several sites.

Circulating Insulin-Like Growth Factor-1 and Risk of Total and 19 Site-Specific Cancers: Cohort Study Analyses from the UK Biobank

BACKGROUND

Insulin-like growth factor-1 (IGF-1) has been implicated in several malignancies, but few studies have examined multiple cancers simultaneously. We sought to conduct systematic assessments of the association between IGF-1 and cancer risk.

METHODS

We conducted a prospective analysis between IGF-1 and incident total and 19 site-specific cancers among 412,645 individuals enrolled in the UK Biobank with follow-up to 2016. IGF-1 was measured using blood samples provided at the baseline examination. HR and 95% confidence interval (CI) were calculated with multivariable-adjusted Cox models with IGF-1 modeled both in sex-specific quintiles and continuously.

RESULTS

Participants were followed for a median of 7.2 years. We observed positive associations between circulating IGF-1 and overall cancer risk for both men (HR = 1.03 per 5-nmol/L increment in IGF-1; 95% CI, 1.01-1.06) and women (HR = 1.03; 95% CI, 1.01-1.06). For specific sites, we observed positive associations for breast (HR = 1.10; 95% CI, 1.07-1.14), prostate (1.09; 95% CI, 1.05-1.12), colorectum (1.07; 95% CI, 1.02-1.11), melanoma (1.08; 95% CI, 1.01-1.15), kidney (1.10; 95% CI, 1.00-1.20), and thyroid (1.22; 95% CI, 1.05-1.42) and inverse associations for lung (0.91; 95% CI, 0.86-0.96), ovaries (0.86; 95% CI, 0.77-0.95), head and neck (0.90; 95% CI, 0.82-0.99), and liver (0.32; 95% CI, 0.26-0.38). The inverse association between IGF-1 and lung cancer was observed only in ever-smokers (HR_ever-smoker = 0.88 vs. HR_never-smoker = 1.14; P_interaction = 0.0005). Analyses comparing extreme quintiles were consistent.

CONCLUSIONS

IGF-1 is modestly associated with increased risk of total cancer in both men and women but demonstrated divergent associations for site-specific cancers.

IMPACT

Our study suggests that IGF-1 could serve as a target for cancer prevention or treatment.

Growth Hormone's Links to Cancer

Several components of the GH axis are involved in tumor progression, and GH-induced intracellular signaling has been strongly associated with breast cancer susceptibility in genome-wide association studies. In the general population, high IGF-I levels and low IGF-binding protein-3 levels within the normal range are associated with the development of common malignancies, and components of the GH-IGF signaling system exhibit correlations with clinical, histopathological, and therapeutic parameters in cancer patients. Despite promising findings in preclinical studies, anticancer therapies targeting the GH-IGF signaling system have led to disappointing results in clinical trials. There is substantial evidence for some degree of protection against tumor development in several animal models and in patients with genetic defects associated with GH deficiency or resistance. In contrast, the link between GH excess and cancer risk in acromegaly patients is much less clear, and cancer screening in acromegaly has been a highly controversial issue. Recent studies have shown that increased life expectancy in acromegaly patients who attain normal GH and IGF-I levels is associated with more deaths due to age-related cancers. Replacement GH therapy in GH deficiency hypopituitary adults and short children has been shown to be safe when no other risk factors for malignancy are present. Nevertheless, the use of GH in cancer survivors and in short children with RASopathies, chromosomal breakage syndromes, or DNA-repair disorders should be carefully evaluated owing to an increased risk of recurrence, primary cancer, or second neoplasia in these individuals.

Targeting the Warburg effect for cancer treatment: Ketogenic diets for management of glioma

Gliomas are a highly heterogeneous tumor, refractory to treatment and the most frequently diagnosed primary brain tumor. Although the current WHO grading system (2016) demonstrates promise towards identifying novel treatment modalities and better prediction of prognosis over time, to date, existing targeted and mono therapy approaches have failed to elicit a robust impact on disease progression and patient survival. It is possible that tumor heterogeneity as well as specifically targeted agents fail because redundant molecular pathways in the tumor make it refractory to such approaches. Additionally, the underlying metabolic pathology, which is significantly altered during neoplastic transformation and tumor progression, is unaccounted for. With several molecular and metabolic pathways implicated in the carcinogenesis of CNS tumors, including glioma, we postulate that a systemic, broad spectrum approach to produce robust targeting of relevant and multiple molecular and metabolic regulation of growth and survival pathways, critical to the modulation of hallmarks of carcinogenesis, without clinically limiting toxicity, may provide a more sustained impact on clinical outcomes compared to the modalities of treatment evaluated to date. The objective of this review is to examine the emerging hallmark of reprogramming energy metabolism of the tumor cells and the tumor microenvironment during carcinogenesis, and to provide a rationale for exploiting this hallmark and its biological capabilities as a target for secondary chemoprevention and treatment of glioma. This review will primarily focus on interventions to induce ketosis to target the glycolytic phenotype of many cancers, with specific application to secondary chemoprevention of low grade glioma- to halt the progression of lower grade tumors to more aggressive subtypes, as evidenced by reduction in validated intermediate endpoints of disease progression including clinical symptoms.

Could IGF-I levels play a neuroprotective role in patients with large vestibular schwannomas?

Aim

To evaluate the possible superiority of outcome in patients with elevated IGF-I levels after vestibular schwannoma (VS) resection.

Patients & methods

This retrospective study included 65 patients (34 male, 52.3%) with VS operated in between January 2009 and April 2014 (follow-up 3.2 ± 0.7 years). Preoperative or postoperative IGF-I levels were identified for each patient.

Results

Patients were divided into two groups: Group A (small size tumor), 56 patients; and Group B (large size tumor), 9 cases. IGF-I levels in Group A (195.8 ± 32.9 ng/ml) were compared with those of Group B (242.2 ± 22.2 ng/ml) and were found to have statistically significant difference (p = 0.001).

Conclusion

Increased IGF-I levels could hold a key role in nerve recovery in patients undergoing surgical resection of large VS.

Overweight, obesity and height as risk factors for meningioma, glioma, pituitary adenoma and nerve sheath tumor: a large population-based prospective cohort study

BACKGROUND

In 2016, the International Agency for Research on Cancer (IARC) has announced that avoiding body fatness (i.e. overweight and obesity) contributes to prevent meningioma occurrence, but considered the available evidence for glioma inadequate. The association of body fatness with other CNS tumor subgroups is largely unknown.

OBJECTIVES

To assess whether body fatness or body height are associated with risk for meningioma, glioma, pituitary adenoma (PA) or nerve sheath tumor (NST) in a large population-based Norwegian cohort.

METHODS

In this prospective cohort study of 1.8 million Norwegian residents, weight and height were measured at baseline and incident intracranial tumors were subsequently identified by linkage to the Cancer Registry of Norway. Cox regression analyses were performed to estimate risk for each tumor subgroup in relation to anthropometric measures, stratified by sex and in different age groups.

RESULTS

During 54 million person-years of follow-up 3335 meningiomas, 4382 gliomas, 1071 PAs and 759 NSTs were diagnosed. Obesity (BMI ≥30 kg/m²) was not associated with risk for meningioma or glioma, but was significantly associated with risk for PA (HR 1.43; 95% CI 1.09-1.88) compared with the reference group (BMI 20-24.9 kg/m²). For intracranial NSTs, obesity was associated with reduced tumor risk (HR 0.68; 95% CI 0.46-0.99). Body height was associated with increased risk for all four tumor subgroups.

CONCLUSIONS

This study does not confirm overweight or obesity as risk factors for meningioma. Additionally, overweight and obesity can be quite confidently excluded as risk factors for glioma. However, this study indicates that body fatness increases the risk for PA, while it reduces the risk for NST.

An Insight into the Increasing Role of LncRNAs in the Pathogenesis of Gliomas

Long non-coding RNAs (LncRNAs) are essential epigenetic regulators with critical roles in tumor initiation and malignant progression. However, the roles and mechanisms of aberrantly expressed lncRNAs in the pathogenesis of gliomas are not fully understood. With the development of deep sequencing analyses, an extensive amount of functional non-coding RNAs has been discovered in glioma tissues and cell lines. Additionally, the contributions of several lncRNAs, such as Hox transcript antisense intergenic RNA, H19 and Colorectal neoplasia differentially expressed, previously reported to be involved in other pathogenesis and processes to the oncogenesis of glioblastoma are currently addressed. Thus, lncRNAs detected in tumor tissues could serve as candidate diagnostic biomarkers and therapeutic targets for gliomas. To understand the potential function of lncRNAs in gliomas, in this review, we briefly describe the profile of lncRNAs in human glioma research and therapy. Then, we discuss the individual lncRNA that has been under intensive investigation in glioma research, and the focus is its mechanism and clinical implication.

A systematic review of the risk factors associated with the onset and progression of primary brain tumours

The overall aim of this systematic review was to identify risk factors for onset and natural progression, which were shown to increase, decrease, or have a null association with risk of primary brain tumour. For onset, the project was separated into two phases. The first phase consisted of a systematic search of existing systematic reviews and meta-analyses. Moderate to high methodological quality reviews were incorporated and summarized with relevant observational studies published since 2010, identified from a systematic search performed in phase 2. For natural progression, only the first phase was conducted. Standard systematic review methodology was utilized. Based on this review, various genetic variants, pesticide exposures, occupational farming/hairdressing, cured meat consumption and personal hair dye use appear to be associated with increased risk of onset amongst adults. The specific EGF polymorphsm 61-A allele within Caucasian populations and having a history of allergy was associated with a decreased risk. For progression, M1B-1 antigen was shown to increase the risk. High birth weight, pesticide exposure (childhood exposure, and parental occupational exposure) and maternal consumption of cured meat during pregnancy may also increase the risk of onset of childhood brain tumours. Conversely, maternal intake of pre-natal supplements (folic acid) appeared to decrease risk. Children with neurofibromatosis 2 were considered to have worse overall and relapse free survival compared to neurofibromatosis 1, as were those children who had grade III tumours compared to lesser grades.

Diabetes, use of antidiabetic drugs, and the risk of glioma

BACKGROUND

Prior epidemiologic studies suggest inverse relations between diabetes and glioma risk, but the underlying mechanisms, including use of antidiabetic drugs, are unknown.

METHODS

We therefore performed a matched case-control analysis using the Clinical Practice Research Datalink (CPRD). We identified incident glioma cases diagnosed between 1995 and 2012 and matched each case with 10 controls on age, gender, calendar time, general practice, and years of active history in the CPRD. We performed conditional logistic regression to estimate odds ratios (ORs) with 95% CIs, adjusted for body mass index and smoking.

RESULTS

We identified 2005 cases and 20 050 controls. Diabetes was associated with decreased risk of glioma (OR = 0.74; 95% CI = 0.60-0.93), particularly glioblastoma (OR = 0.69; 95% CI = 0.51-0.94). Glioblastoma risk reduction was markedly pronounced among diabetic men (OR = 0.60; 95% CI = 0.40-0.90), most apparently for those with diabetes of long-term duration (OR for >5 vs 0 y = 0.46; 95% CI = 0.26-0.82) or poor glycemic control (OR for HbA1c ≥ 8 vs <6.5% = 0.20; 95% CI = 0.06-0.70). In contrast, the effect of diabetes on glioblastoma risk was absent among women (OR = 0.85; 95% CI = 0.53-1.36). No significant associations with glioma were found for use of metformin (OR for ≥ 30 vs 0 prescriptions = 0.72; 95% CI = 0.38-1.39), sulfonylureas (OR = 0.71; 95% CI = 0.39-1.30), or insulin (OR = 0.79; 95% CI = 0.37-1.69).

CONCLUSIONS

Antidiabetic treatment appears to be unrelated to glioma, but long-term diabetes duration and increased HbA1c both show decreased glioma risk. Stronger findings in men than women suggest low androgen levels concurrent with diabetes as a biologic mechanism.

Inhibition of intracerebral glioblastoma growth by targeting the insulin-like growth factor 1 receptor involves different context-dependent mechanisms

BACKGROUND

Signaling by insulin-like growth factor 1 receptor (IGF-1R) can contribute to the formation and progression of many diverse tumor types, including glioblastoma. We investigated the effect of the IGF-1R blocking antibody IMC-A12 on glioblastoma growth in different in vivo models.

METHODS

U87 cells were chosen to establish rapidly growing, angiogenesis-dependent tumors in the brains of nude mice, and the GS-12 cell line was used to generate highly invasive tumors. IMC-A12 was administered using convection-enhanced local delivery. Tumor parameters were quantified histologically, and the functional relevance of IGF-1R activation was analyzed in vitro.

RESULTS

IMC-A12 treatment inhibited the growth of U87 and GS-12 tumors by 75% and 50%, respectively. In GS-12 tumors, the invasive tumor extension and proliferation rate were significantly reduced by IMC-A12 treatment, while apoptosis was increased. In IMC-A12-treated U87 tumors, intratumoral vascularization was markedly decreased, and tumor cell proliferation was moderately reduced. Flow cytometry showed that <2% of U87 cells but >85% of GS-12 cells expressed IGF-1R. Activation of IGF-1R by IGF-1 and IGF-2 in GS-12 cells was blocked by IMC-A12. Both ligands stimulated GS-12 cell proliferation, and IGF-2 also stimulated migration. IMC-A12 inhibited these stimulatory effects and increased apoptosis. In U87 cells, stimulation with either ligand had no functional effect.

CONCLUSIONS

IGF-1R blockade can inhibit glioblastoma growth by different mechanisms, including direct effects on the tumor cells as well as indirect anti-angiogenic effects. Hence, blocking IGF-1R may be useful to target both the highly proliferative, angiogenesis-dependent glioblastoma core component as well as the infiltrative periphery.

Perinatal and familial risk factors for brain tumors in childhood through young adulthood

Perinatal factors, including high birth weight, have been associated with childhood brain tumors in case-control studies. However, the specific contributions of gestational age and fetal growth remain unknown, and these issues have never been examined in large cohort studies with follow-up into adulthood. We conducted a national cohort study of 3,571,574 persons born in Sweden in 1973-2008, followed up for brain tumor incidence through 2010 (maximum age 38 years) to examine perinatal and familial risk factors. There were 2,809 brain tumors in 69.7 million person-years of follow-up. After adjusting for potential confounders, significant risk factors for brain tumors included high fetal growth [incidence rate ratio (IRR) per additional 1 SD, 1.04; 95% confidence interval (CI), 1.01-1.08, P = 0.02], first-degree family history of a brain tumor (IRR, 2.43; 95% CI, 1.86-3.18, P < 0.001), parental country of birth (IRR for both parents born in Sweden vs. other countries, 1.21; 95% CI, 1.09-1.35, P < 0.001), and high maternal education level (Ptrend = 0.01). These risk factors did not vary by age at diagnosis. The association with high fetal growth appeared to involve pilocytic astrocytomas, but not other astrocytomas, medulloblastomas, or ependymomas. Gestational age at birth, birth order, multiple birth, and parental age were not associated with brain tumors. In this large cohort study, high fetal growth was associated with an increased risk of brain tumors (particularly pilocytic astrocytomas) independently of gestational age, not only in childhood but also into young adulthood, suggesting that growth factor pathways may play an important long-term role in the etiology of certain brain tumor subtypes.

A prospective study of height and body mass index in childhood, birth weight, and risk of adult glioma over 40 years of follow-up

Greater attained height and greater body mass index (BMI; weight (kg)/height (m)(2)) in young adulthood have been associated with glioma risk, but few studies have investigated the association with body size at birth or during childhood, when the brain undergoes rapid cell growth and differentiation. The Copenhagen School Health Records Register includes data on 320,425 Danish schoolchildren born between 1930 and 1989, with height and weight measurements from ages 7-13 years and parentally recorded birth weights. We prospectively evaluated associations between childhood height and BMI, birth weight, and adult glioma risk. During follow-up (1968-2010), 355 men and 253 women aged ≥18 years were diagnosed with glioma. In boys, height at each age between 7 and 13 years was positively associated with glioma risk; hazard ratios per standard-deviation score at ages 7 (approximately 5.1 cm) and 13 (approximately 7.6 cm) years were 1.17 (95% confidence interval (CI): 1.05, 1.30) and 1.21 (95% CI: 1.09, 1.35), respectively. No associations were observed for childhood height in girls or for BMI. Birth weight was positively associated with risk (per 0.5 kg: hazard ratio = 1.13, 95% CI: 1.04, 1.24). These results suggest that exposures associated with higher birth weight and, in boys, greater height during childhood may contribute to the etiology of adult glioma.

Biomarker patterns of inflammatory and metabolic pathways are associated with risk of colorectal cancer: results from the European Prospective Investigation into Cancer and Nutrition (EPIC)

A number of biomarkers of inflammatory and metabolic pathways are individually related to higher risk of colorectal cancer (CRC); however, the association between biomarker patterns and CRC incidence has not been previously evaluated. Our study investigates the association of biomarker patterns with CRC in a prospective nested case-control study within the European Prospective Investigation into Cancer and Nutrition (EPIC). During median follow-up time of 7.0 (3.7-9.4) years, 1,260 incident CRC cases occurred and were matched to 1,260 controls using risk-set sampling. Pre-diagnostic measurements of C-peptide, glycated hemoglobin, triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), C-reactive protein (CRP), reactive oxygen metabolites (ROM), insulin-like growth factor 1, adiponectin, leptin and soluble leptin receptor (sOB-R) were used to derive biomarker patterns from principal component analysis (PCA). The relation with CRC incidence was assessed using conditional logistic regression models. We identified four biomarker patterns 'HDL-C/Adiponectin fractions', 'ROM/CRP', 'TG/C-peptide' and 'leptin/sOB-R' to explain 60 % of the overall biomarker variance. In multivariable-adjusted logistic regression, the 'HDL-C/Adiponectin fractions', 'ROM/CRP' and 'leptin/sOB-R' patterns were associated with CRC risk [for the highest quartile vs the lowest, incidence rate ratio (IRR) = 0.69, 95 % CI 0.51-0.93, P-trend = 0.01; IRR = 1.70, 95 % CI 1.30-2.23, P-trend = 0.002; and IRR = 0.79, 95 % CI 0.58-1.07; P-trend = 0.05, respectively]. In contrast, the 'TG/C-peptide' pattern was not associated with CRC risk (IRR = 0.75, 95 % CI 0.56-1.00, P-trend = 0.24). After cases within the first 2 follow-up years were excluded, the 'ROM/CRP' pattern was no longer associated with CRC risk, suggesting potential influence of preclinical disease on these associations. By application of PCA, the study identified 'HDL-C/Adiponectin fractions', 'ROM/CRP' and 'leptin/sOB-R' as biomarker patterns representing potentially important pathways for CRC development.

Plasma levels of glucose and insulin in patients with brain tumors

In the last years there were many authors that suggest the existence of an association between different components of metabolic syndrome and various cancers. Two important components of metabolic syndrome are hyperglycemia and hyperinsulinemia. Both of them had already been linked with the increased risk of pancreatic, breast, endometrial or prostate cancer. However the correlation of the level of the glucose and insulin with various types and grades of brain tumors remains unclear. In this article we have analysed the values of plasma glucose and insulin in 267 patients, consecutively diagnosed with various types of brain tumors. Our results showed no correlation between the glycemia and brain tumor types or grades. High plasma levels of insulin were found in brain metastasis and astrocytomas while the other types of brain tumors (meningiomas and glioblastomas) had lower levels of the peptide. The levels of insulin were also higher in brain metastasis and grade 3 brain tumors when compared with grade 1, grade 2 and grade 4 brain tumors.

Phosphorylated insulin-like growth factor-1 receptor (pIGF1R) is a poor prognostic factor in brain metastases from lung adenocarcinomas

A greater understanding of brain metastases is imperative for developing novel therapeutic strategies. Our previous study showed that insulin-like growth factor (IGF) signaling pathway was activated in brain-tropic cancer cells. In this study, we investigated the clinical relevance of activated (phosphorylated) IGF-1 receptor (pIGF1R) expression in brain metastases originating from lung adenocarcinomas. All pathologically confirmed brain metastases from lung adenocarcinomas, with available archived specimens from January 1998 to December 2009 at National Taiwan University Hospital, were assessed immunohistochemically for pIGF1R expression using H-score criteria. A median H-score was used as a cutoff point to define high or low pIGF1R expression. The mutation status in the tyrosine kinase domain of the epidermal growth factor receptor (EGFR) was examined using direct sequencing. The prognostic significance of pIGF1R expression, its correlations with clinicopathological characteristics, and EGFR status were evaluated. In the 86 cases, high membranous/cytoplasmic pIGF1R expression in brain metastases correlated with a shorter median survival (10.8 vs 27.8 mo, P = 0.003). This correlation was more significant in patients with EGFR mutations [hazard ratio (HR) 2.38, 95 % confidence interval (CI) 1.19-4.77 for EGFR mutations; HR 1.99, 95 % CI 0.95-4.15 for EGFR wild type] and remained statistically significant in multivariate analysis after adjusting for the effects of other potential prognostic factors, including the graded prognostic assessment score, solitary brain metastasis, extracranial metastatic status, EGFR mutations, and treatment using EGFR tyrosine kinase inhibitors. Although we also identified nuclear pIGF1R expression, this result was prognostically non-significant. Our study results showed that high membranous/cytoplasmic pIGF1R expression in brain metastases was a poor prognostic factor, more significantly in patients with EGFR mutations than in those with wild-type EGFRs.

Diabetes mellitus and risk of brain tumors: A meta-analysis

Accumulating evidence suggests that a history of diabetes may be involved in the occurrence of various types of cancer. However, the association of diabetes with the risk of brain tumors remains unclear. We identified relevant studies by performing a literature search of PubMed and EMBASE (through to 24 May 2012) and by searching the reference lists of pertinent articles. All data were extracted independently by two investigators using a standardized data abstraction tool. Summary relative risks (SRRs) with 95% confidence intervals (CIs) were calculated using a random-effects model. Inter-study heterogeneity was assessed using the Cochran’s Q and I² statistical tests. A total of 13 studies were included in this meta-analysis, including the entire Danish population, 5,107,506 other participants and more than 2,206 cases of brain tumors. In the analysis of these 13 studies, we observed that diabetic individuals had a similar risk of brain tumors as non-diabetic individuals (SRR, 1.12; 95% CI, 0.89–1.42). There was significant evidence of heterogeneity among these studies (P<0.001; I², 93.5%). Sub-group analysis revealed that diabetic females had a 24.2% increased risk of brain tumors (SRR, 1.242; 95% CI, 1.026–1.502), which was not observed in diabetic males. No significant publication bias was found in this study. The findings of this meta-analysis indicate that diabetic individuals have a similar risk of brain tumors as non-diabetic individuals. However, a significant positive correlation between the risk of brain tumors and diabetes mellitus was revealed in females, but not in males.

Therapeutic potential of anamorelin, a novel, oral ghrelin mimetic, in patients with cancer-related cachexia: a multicenter, randomized, double-blind, crossover, pilot study

PURPOSE

Cachexia in cancer adversely affects patients' perception of symptoms, well-being, and response to therapy, and shortens survival. Anamorelin, an oral mimetic of ghrelin, has been shown to increase body weight and anabolic hormone levels in healthy volunteers and is being investigated to treat cancer cachexia.

METHODS

This multicenter, double-blind, placebo-controlled, crossover study evaluated the effects of anamorelin in 16 patients with different cancers and cachexia. Patients were randomly assigned to anamorelin 50 mg/day or placebo for 3 days. A 3- to 7-day washout period followed and then treatments were switched. Assessments included body weight, appetite, food intake, growth hormone (GH) levels, patient-reported symptom assessments (e.g., the Anderson Symptom Assessment Scale [ASAS] and also an inclusion criterion), and safety.

RESULTS

Anamorelin significantly increased body weight compared with placebo (0.77 kg vs. -0.33 kg). Food intake increased compared with placebo, but not significantly. GH significantly increased at all time points (0.5-4 h postdose). Insulin-like growth factor-1 (IGF-1) significantly increased by 54.09 ng/mL with anamorelin treatment compared with -3.56 ng/mL for placebo; significant changes in insulin-like growth factor-binding protein 3 (IGFBP-3) were 0.75 μg/mL vs. -0.19 μg/mL, respectively. Patient-reported symptoms, including appetite as measured by ASAS, significantly improved with anamorelin (8.1 vs. 1.0 for placebo). Adverse events (AEs) in four patients were possibly or probably related to anamorelin: hyperglycemia (two patients), nausea (one patient), and dizziness (one patient). Most AEs were mild; no patients withdrew due to AEs.

CONCLUSIONS

Anamorelin showed significant metabolic, clinical, and patient-rated effects in cancer cachexia. Further studies are warranted.