The association between cancer-related fatigue and diabetes from pre-chemotherapy to 6 months post-chemotherapy.

PURPOSE: To quantify the relationship between diabetes and fatigue from pre-chemotherapy to 6 months post-chemotherapy for women with breast cancer compared to women without a history of cancer (controls). METHODS: This was a secondary analysis from a nationwide prospective longitudinal study of female patients with breast cancer undergoing chemotherapy and controls. Diabetes diagnosis (yes/no) was obtained at baseline, and cancer-related fatigue was measured using the Multidimensional Fatigue Symptom Inventory (MFSI) pre-, post-, and 6 months post-chemotherapy in patients; controls were assessed at equivalent time points. Repeated measures mixed effects models estimated the association between fatigue and diabetes controlling for cancer (yes/no), body mass index, exercise and smoking habits, baseline anxiety and depressive symptoms, menopausal status, marital status, race, and education. RESULTS: Among 439 patients and 235 controls (52.8 ± 10.5 years old), diabetes was twice as prevalent among patients as controls (11.6% vs. 6.8%). At baseline, diabetes was associated with worse fatigue (4.1 ± 1.7 points, p = 0.017). Also, diabetes was associated with clinically meaningful worse fatigue throughout the study period among all participants (5.2 ± 1.9 points, p = 0.008) and patients alone (4.5 ± 2.0, p = 0.023). For the MFSI subdomains among patients, diabetes was associated with worse general (p = 0.005) and mental fatigue (p = 0.026). CONCLUSIONS: Diabetes was twice as prevalent in women with breast cancer compared to controls, and diabetes was associated with more severe cancer-related fatigue in patients before and after chemotherapy and at 6 months post-chemotherapy. Interventions that address diabetes management may also help address cancer-related fatigue during chemotherapy treatment. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01382082, first posted June 27, 2011.

Gas6 induces inflammation and reduces plaque burden but worsens behavior in a sex-dependent manner in the APP/PS1 model of Alzheimer's disease.

BACKGROUND: Alzheimer's disease is the leading cause of dementia worldwide. TAM receptor tyrosine kinases (Tyro3, Axl, MerTK) are known for their role in engagement of phagocytosis and modulation of inflammation, and recent evidence suggests a complex relationship between Axl, Mer, and microglial phagocytosis of amyloid plaques in AD. Gas6, the primary CNS TAM ligand, reduces neuroinflammation and improves outcomes in murine models of CNS disease. Therefore, we hypothesized that AAV-mediated overexpression of Gas6 would alleviate plaque pathology, reduce neuroinflammation, and improve behavior in the APP/PS1 model of Alzheimer's disease. METHODS: Adeno-associated viral vectors were used to overexpress Gas6 in the APP/PS1 model of Alzheimer's disease. Nine-month-old male and female APP/PS1 and nontransgenic littermates received bilateral stereotactic hippocampal injections of AAV-Gas6 or AAV-control, which expresses a non-functional Gas6 protein. One month after injections, mice underwent a battery of behavioral tasks to assess cognitive function and brains were processed for immunohistochemical and transcriptional analyses. RESULTS: Gas6 overexpression reduced plaque burden in male APP/PS1 mice. However, contrary to our hypothesis, Gas6 increased pro-inflammatory microglial gene expression and worsened contextual fear conditioning compared to control-treated mice. Gas6 overexpression appeared to have no effect on phagocytic mechanisms in vitro or in vivo as measured by CD68 immunohistochemistry, microglial methoxy-04 uptake, and primary microglial uptake of fluorescent fibrillar amyloid beta. CONCLUSION: Our data describes a triad of worsened behavior, reduced plaque number, and an increase in proinflammatory signaling in a sex-specific manner. While Gas6 has historically induced anti-inflammatory signatures in the peripheral nervous system, our data suggest an alternative, proinflammatory role in the context of Alzheimer's disease pathology.

Inflammation, Attention, and Processing Speed in Patients With Breast Cancer Before and After Chemotherapy.

BACKGROUND: Inflammation may contribute to cognitive difficulties in patients with breast cancer. We tested 2 hypotheses: inflammation is elevated in patients with breast cancer vs noncancer control participants and inflammation in patients is associated with worse attention and processing speed over the course of chemotherapy. METHODS: Serum cytokines (interleukin [IL]-4, 6, 8, 10; tumor necrosis factor [TNF]-α) and soluble receptors [sTNFRI, II]) were measured in 519 females with breast cancer before and after chemotherapy and 338 females without cancer serving as control participants. Attention and processing speed were measured by Rapid Visual Processing (RVP), Backward Counting (BCT), and Trail Making-A (TMT-A) tests. Linear regression models examined patient vs control cytokines and receptor levels, adjusting for covariates. Linear regression models also examined relationships between patient cytokines and receptor levels and test performance, adjusting for age, body mass index, anxiety, depression, cognitive reserve, and chemotherapy duration. Statistical tests were 2-sided (α = .05). RESULTS: sTNFRI and sTNFRII increased over time in patients relative to controls, whereas IL-4, IL-6, and IL-10 decreased. Prechemotherapy, higher IL-8 associated with worse BCT (ß = 0.610, SE = 0.241, P = .01); higher IL-4 (ß = -1.098, SE = 0.516, P = .03) and IL-10 (ß = -0.835, SE = 0.414, P = .04) associated with better TMT-A. Postchemotherapy, higher IL-8 (ß = 0.841, SE = 0.260, P = .001), sTNFRI (ß = 6.638, SE = 2.208, P = .003), and sTNFRII (ß = 0.913, SE = 0.455, P = .045) associated with worse BCT; higher sTNFRII also associated with worse RVP (ß = -1.316, SE = 0.587, P = .03). At prechemotherapy, higher IL-4 predicted RVP improvement over time (ß = 0.820, SE = 0.336, P = .02); higher sTNFRI predicted worse BCT over time (ß = 5.566, SE = 2.367, P = .02). Longitudinally, increases in IL-4 associated with BCT improvement (ß = -0.564, SE = 0.253, P = .03). CONCLUSIONS: Generally, worse attention and processing speed were associated with higher inflammatory cytokines and receptors and lower anti-inflammatory cytokines in patients; future confirmatory studies are needed.

Longitudinal Changes in Cognitive Function in a Nationwide Cohort Study of Patients With Lymphoma Treated With Chemotherapy.

BACKGROUND: Cancer-related cognitive decline (CRCD) is an important clinical problem, but limited research exists on assessment of cognitive function in patients with lymphoma. METHODS: The overall objective of this nationwide, prospective, observational study conducted in the National Cancer Institute Community Clinical Oncology Research Program (NCORP) was to assess changes in memory, attention, and executive function in patients with lymphoma from pre- (A1) to postchemotherapy (A2) and to 6 months postchemotherapy (A3). Individuals without cancer served as noncancer controls, paired to patients by age and sex, and assessed at the same time-equivalent points. Longitudinal linear mixed models (LMM) including A1, A2, and A3 and adjusting for age, education, race, sex, cognitive reserve score, baseline anxiety, and depressive symptoms were fit. We assessed changes in patients compared with control participants without cancer and assessed differences in cognitive function in those patients with Hodgkin vs non-Hodgkin disease and by disease subtype. All statistical tests were 2-sided. RESULTS: Patients with lymphoma (n = 248) and participants without cancer serving as controls (n = 212) were recruited from 19 NCORP sites. From pre- to postchemotherapy and from prechemotherapy to 6 months follow-up, patients reported more cognitive problems over time compared with controls (Functional Assessment of Cancer-Therapy-Cognitive Function [FACT-Cog] perceived cognitive impairment effect size (ES) = 0.83 and 0.84 for A1 to A2 and A1 to A3, respectively; P < .001; single-item cognitive symptoms ES range = 0.55 to 0.70 inclusive of A1 to A2 and A1 to A3; P < .001); the complaints were more pronounced in women with lymphoma compared with men with lymphoma (FACT-Cog Perceived Cognitive Impairment (PCI) score group-by-time-by-sex interaction, P = .007). Patients with lymphoma also performed statistically significantly less well on tests of verbal memory and delayed recall, attention and executive function, and telephone-based category fluency. CONCLUSION: Patients with lymphoma experience worse patient-reported and objectively assessed cognitive function from prechemotherapy to 6-month follow-up compared with age- and sex-paired controls without cancer assessed at similar time intervals.

Evaluating Effects of Glatiramer Acetate Treatment on Amyloid Deposition and Tau Phosphorylation in the 3xTg Mouse Model of Alzheimer's Disease.

Neuroinflammation driven by the accumulation of amyloid ß (Aß) can lead to neurofibrillary tangle formation in Alzheimer's Disease (AD). To test the hypothesis that an anti-inflammatory immunomodulatory agent might have beneficial effects on amyloid and tau pathology, as well as microglial phenotype, we evaluated glatiramer acetate (GA), a multiple sclerosis drug thought to bias type 2 helper T (Th2) cell responses and alternatively activate myeloid cells. We administered weekly subcutaneous injections of GA or PBS to 15-month-old 3xTg AD mice, which develop both amyloid and tau pathology, for a period of 8 weeks. We found that subcutaneous administration of GA improved behavioral performance in novel object recognition and decreased Aß plaque in the 3xTg AD mice. Changes in tau phosphorylation were mixed with specific changes in phosphoepitopes seen in immunohistochemistry but not observed in western blot. In addition, we found that there was a trend toward increased microglia complexity in 3xTg mice treated with GA, suggesting a shift toward homeostasis. These findings correlated with subtle changes in the microglial transcriptome, in which the most striking difference was the upregulation of Dcstamp. Lastly, we found no evidence of changes in proportions of major helper T cell (Th) subtypes in the periphery. Overall, our study provides further evidence for the benefits of immunomodulatory therapies that alter the adaptive immune system with the goal of modifying microglia responses for the treatment of Alzheimer's Disease.

Health related quality of life in adult cancer survivors: Importance of social and emotional support.

BACKGROUND: Adult cancer survivors (ACS) are at increased risk for developing various comorbid conditions and having poor health-related quality of life (HRQOL) when compared to adults with no history of cancer. The effect of social and emotional support on HRQOL among ACS is not fully elucidated. The purpose of this study was to understand the role of social and emotional support on HRQOL in ACS and to examine if the association between social and emotional support and HRQOL is modified by gender, time since cancer diagnosis, or marital status. METHODS: Data for this study were obtained from the 2009 Behavioral Risk Factor Surveillance System. Statistical analysis was based on ACS with complete data (n = 23,939) on all variables considered. Multivariable logistic regression models were used to model the association between social and emotional support and indicators of HRQOL (i.e., general health, physical health, mental health, and activity limitation). To examine if gender, marital status, or the number of years since cancer diagnosis modify the association, separate stratified analyses were conducted. RESULTS: When compared to ACS who reported that they Rarely/Never received social and emotional support, those who reported that they Always received were 32 % less likely to report Fair/Poor General health, 23 % less likely to report frequent unhealthy days of Physical health, 73 % less likely to report frequent unhealthy days of Mental health and 38 % less likely to report frequent unhealthy days of Activity limitation. Social and emotional support was positively associated with all four domains of HRQOL among ACS who were female, unmarried, or greater than 5 years since cancer diagnosis, while this positive association was evident only with one or two domains of HRQOL among their corresponding counterparts (i.e., male, married, less than 5 years since diagnosis). CONCLUSIONS: Social and emotional support is an important factor directly related to a better HRQOL, but it is modified by gender, marital status, and time since diagnosis. Findings from this study should inform health care providers about the importance of a support system for ACS in improving their overall quality of life.

Review of the Role of the Brain in Chemotherapy-Induced Peripheral Neuropathy.

Chemotherapy-induced peripheral neuropathy (CIPN) is a common, debilitating, and dose-limiting side effect of many chemotherapy regimens yet has limited treatments due to incomplete knowledge of its pathophysiology. Research on the pathophysiology of CIPN has focused on peripheral nerves because CIPN symptoms are felt in the hands and feet. However, better understanding the role of the brain in CIPN may accelerate understanding, diagnosing, and treating CIPN. The goals of this review are to (1) investigate the role of the brain in CIPN, and (2) use this knowledge to inform future research and treatment of CIPN. We identified 16 papers using brain interventions in animal models of CIPN and five papers using brain imaging in humans or monkeys with CIPN. These studies suggest that CIPN is partly caused by (1) brain hyperactivity, (2) reduced GABAergic inhibition, (3) neuroinflammation, and (4) overactivation of GPCR/MAPK pathways. These four features were observed in several brain regions including the thalamus, periaqueductal gray, anterior cingulate cortex, somatosensory cortex, and insula. We discuss how to leverage this knowledge for future preclinical research, clinical research, and brain-based treatments for CIPN.

Nutritional Status Predicts Fatty Acid Uptake from Fish and Soybean Oil Supplements for Treatment of Cancer-Related Fatigue: Results from a Phase II Nationwide Study.

Cancer-related fatigue is a prevalent and debilitating condition that persists for years into survivorship. Studies evaluating both fish oil supplementation on fatigue and associations between fish oil consumption and fatigue have shown mixed effects; it is unknown what factors contribute to these differential effects. Herein, we investigate whether the nutritional status of cancer survivors was associated with serum omega-3 concentration or change in serum omega-3s throughout a fish oil supplementation study, and then if any of these factors were associated with fatigue. Breast cancer survivors 4-36 months post-treatment with moderate-severe fatigue were randomized to take 6 g fish oil, 6 g soybean oil, or 3 g of each daily for 6 weeks. Baseline nutritional status was calculated using the Controlling Nutritional Status tool (serum albumin, lymphocytes, cholesterol). At baseline and post-intervention, serum fatty acids were quantified and fatigue was assessed using the Multidimensional Fatigue Symptom Inventory. Participants (n = 85) were 61.2 ± 9.7 years old with a body mass index of 31.9 ± 6.7 kg/m2; 69% had a good nutritional score and 31% had light-moderate malnutrition. Those with good nutritional status had greater total serum omega-3s at baseline (p = 0.013) and a greater increase in serum omega-3s with supplementation (p = 0.003). Among those who were supplemented with fish oil, greater increases in serum omega-3s were associated with greater improvements in fatigue. In conclusion, good nutritional status may increase uptake of fatty acid supplements, increasing their ability to improve fatigue.

Cranial irradiation acutely and persistently impairs injury-induced microglial proliferation.

Microglia, the resident immune cells of the central nervous system (CNS), play multiple roles in maintaining CNS homeostasis and mediating tissue repair, including proliferating in response to brain injury and disease. Cranial irradiation (CI), used for the treatment of brain tumors, has a long-lasting anti-proliferative effect on a number of cell types in the brain, including oligodendrocyte progenitor and neural progenitor cells; however, the effect of CI on CNS-resident microglial proliferation is not well characterized. Using a sterile cortical needle stab injury model in mice, we found that the ability of CNS-resident microglia to proliferate in response to injury was impaired by prior CI, in a dose-dependent manner, and was nearly abolished by a 20 â€‹Gy dose. Similarly, in a metastatic tumor model, prior CI (20 â€‹Gy) reduced microglial proliferation in response to tumor growth. The effect of irradiation was long-lasting; 20 â€‹Gy CI 6 months prior to stab injury significantly impaired microglial proliferation. We also investigated how stab and/or irradiation impacted levels of P2Y12R, CD68, CSF1, IL-34 and CSF1R, factors involved in the brain's normal response to injury. P2Y12R, CD68, CSF1, and IL-34 expression were altered by stab similarly in irradiated mice and controls; however, CSF1R was differentially affected. qRT-PCR and flow cytometry analyses demonstrated that CI reduced overall Csf1r mRNA levels and microglial specific CSF1R protein expression, respectively. Interestingly, Csf1r mRNA levels increased after injury in unirradiated controls; however, Csf1r levels were persistently decreased in irradiated mice, and did not increase in response to stab. Together, our data demonstrate that CI leads to a significant and lasting impairment of microglial proliferation, possibly through a CSF1R-mediated mechanism.

Space radiation does not alter amyloid or tau pathology in the 3xTg mouse model of Alzheimer's disease.

Space radiation is comprised of highly charged ions (HZE particles) and protons that are able to pass through matter and cause radiation-induced injury, including neuronal damage and degeneration, glial activation, and oxidative stress. Previous work demonstrated a worsening of Alzheimer's disease pathology in the APP/PS1 transgenic mouse model, however effects of space radiation on tau pathology have not been studied. To determine whether tau pathology is altered by HZE particle or proton irradiation, we exposed 3xTg mice, which acquire both amyloid plaque and tau pathology with age, to iron, silicon, or solar particle event (SPE) irradiation at 9 months of age and evaluated behavior and brain pathology at 16 months of age. We found no differences in performance in fear conditioning and novel object recognition tasks between groups of mice exposed to sham, iron (10 and 100 cGy), silicon (10 and 100 cGy), or solar particle event radiation (200 cGy), though female mice had higher freezing responses than males. 200 cGy SPE irradiated female mice had fewer plaques than sham-irradiated females but had no differences in tau pathology. Overall, females had worse amyloid and tau pathology at 16 months of age and demonstrated a reduced neuroinflammatory gene expression response to radiation. These findings uncover differences between mouse models following radiation injury and corroborate prior reports of sex differences within the 3xTg mouse model.

Sympathetic innervation, norepinephrine content, and norepinephrine turnover in orthotopic and spontaneous models of breast cancer.

Activation of the sympathetic nervous system (SNS) drives breast cancer progression in preclinical breast cancer models, but it has yet to be established if neoplastic and stromal cells residing in the tumor are directly targeted by locally released norepinephrine (NE). In murine orthotopic and spontaneous mammary tumors, tyrosine hydroxylase (TH)+ sympathetic nerves were limited to the periphery of the tumor. No TH+ staining was detected deeper within these tumors, even in regions with a high density of blood vessels. NE concentration was much lower in tumors compared to the more densely innervated spleen, reflecting the relative paucity of tumor TH+ innervation. Tumor and spleen NE concentration decreased with increased tissue mass. In mice treated with the neurotoxin 6-hydroxydopamine (6-OHDA) to selectively destroy sympathetic nerves, tumor NE concentration was reduced approximately 50%, suggesting that the majority of tumor NE is derived from local sympathetic nerves. To evaluate NE utilization, NE turnover in orthotopic 4T1 mammary tumors was compared to spleen under baseline and stress conditions. In non-stressed mice, NE turnover was equivalent between tumor and spleen. In mice exposed to a stressor, tumor NE turnover was increased compared to spleen NE turnover, and compared to non-stressed tumor NE turnover. Together, these results demonstrate that NE in mammary tumors is derived from local sympathetic nerves that synthesize and metabolize NE. However, differences between spleen and tumor NE turnover with stressor exposure suggest that sympathetic NE release is regulated differently within the tumor microenvironment compared to the spleen. Local mammary tumor sympathetic innervation, despite its limited distribution, is responsive to stressor exposure and therefore can contribute to stress-induced tumor progression.