Allelic variation to the APOE gene confers the greatest genetic risk for sporadic Alzheimer's disease (AD). Independent of genotype, low abundance of apolipoprotein E (apoE), is characteristic of AD ...CSF, and predicts cognitive decline. The mechanisms underlying the genotype and apoE level risks are uncertain. Recent fluid and imaging biomarker studies have revealed an unexpected link between apoE and brain iron, which also forecasts disease progression, possibly through ferroptosis, an iron-dependent regulated cell death pathway. Here, we report that apoE is a potent inhibitor of ferroptosis (EC
≈ 10 nM; N27 neurons). We demonstrate that apoE signals to activate the PI3K/AKT pathway that then inhibits the autophagic degradation of ferritin (ferritinophagy), thus averting iron-dependent lipid peroxidation. Using postmortem inferior temporal brain cortex tissue from deceased subjects from the Rush Memory and Aging Project (MAP) (N = 608), we found that the association of iron with pathologically confirmed clinical Alzheimer's disease was stronger among those with the adverse APOE-ε4 allele. While protection against ferroptosis did not differ between apoE isoforms in vitro, other features of ε4 carriers, such as low abundance of apoE protein and higher levels of polyunsaturated fatty acids (which fuel ferroptosis) could mediate the ε4 allele's heighted risk of AD. These data support ferroptosis as a putative pathway to explain the major genetic risk associated with late onset AD.
Copper is an essential micronutrient for brain health and dyshomeostasis of copper could have a pathophysiological role in Alzheimer's disease (AD), however, there are limited data from ...community-based samples. In this study, we investigate the association of brain copper (assessed using ICP-MS in four regions -inferior temporal, mid-frontal, anterior cingulate, and cerebellum) and dietary copper with cognitive decline and AD pathology burden (a quantitative summary of neurofibrillary tangles, diffuse and neuritic plaques in multiple brain regions) at autopsy examination among deceased participants (N = 657; age of death: 90.2(±6.2)years, 70% women, 25% APOE-ɛ4 carriers) in the Rush Memory and Aging Project. During annual visits, these participants completed cognitive assessments using a 19-test battery and dietary assessments (using a food frequency questionnaire). Regression, linear mixed-effects, and logistic models adjusted for age at death, sex, education, and APOE-ε4 status were used. Higher composite brain copper levels were associated with slower cognitive decline (β(SE) = 0.028(0.01), p = 0.001) and less global AD pathology (β(SE) = -0.069(0.02), p = 0.0004). Participants in the middle and highest tertile of dietary copper had slower cognitive decline (T2vs.T1: β = 0.038, p = 0.0008; T3vs.T1: β = 0.028, p = 0.01) than those in the lowest tertile. Dietary copper intake was not associated with brain copper levels or AD pathology. Associations of higher brain copper levels with slower cognitive decline and with less AD pathology support a role for copper dyshomeostasis in AD pathogenesis and suggest that lower brain copper may exacerbate or indicate disease severity. Dietary and brain copper are unrelated but dietary copper is associated with slower cognitive decline via an unknown mechanism.
Epirubicin, oxaliplatin, and capecitabine (EOC) is a standard treatment in advanced esophagogastric cancer. Panitumumab (P) is a fully human, immunoglobulin G2 monoclonal antibody targeting epidermal ...growth factor receptor. Randomized Trial of EOC +/- Panitumumab for Advanced and Locally Advanced Esophagogastric Cancer (REAL-3) will evaluate whether the addition of P to EOC improves survival in patients with advanced esophagogastric adenocarcinoma and undifferentiated carcinoma.
The original design of REAL-3 added P 9 mg/kg to the standard dose of EOC (dose level DL + 1). Due to toxicity, a dose de-escalation was made to EOC + P DL-1 (epirubicin 50 mg/m(2), oxaliplatin130 mg/m(2), capecitabine 1,000 mg/m(2)/d + P 9 mg/kg every 3 weeks). After additional toxicity was observed, the study was amended to include two additional EOC + P dose levels. Using a 3 + 3 design, dose-limiting toxicities (DLTs) were assessed weekly during cycle 1. Patients were randomly assigned 1:1 to EOC +/- P.
Between July 2008 and October 2009, 29 patients were randomly selected for standard-dose EOC (n = 13) or EOC + P (n = 16). Five patients were treated at DL + 1, with grade 3 diarrhea in four of five patients by cycle 4. At DL-1, one patient had grade 3 diarrhea and grade 5 infection. Three patients were treated at DL-3, and then six were treated at DL-2, without DLTs.
The recommended dose for EOC + P is epirubicin 50 mg/m(2), oxaliplatin 100 mg/m(2), capecitabine 1,000 mg/m(2)/d, and P 9 mg/kg every 3 weeks. This dose has been selected for the ongoing phase II/III REAL-3 study.
Abstract
High-throughput digital pathology offers considerable advantages over traditional semiquantitative and manual methods of counting pathology. We used brain tissue from 5 clinical-pathologic ...cohort studies of aging; the Religious Orders Study, the Rush Memory and Aging Project, the Minority Aging Research Study, the African American Clinical Core, and the Latino Core to (1) develop a workflow management system for digital pathology processes, (2) optimize digital algorithms to quantify Alzheimer disease (AD) pathology, and (3) harmonize data statistically. Data from digital algorithms for the quantification of β-amyloid (Aβ, n = 413) whole slide images and tau-tangles (n = 639) were highly correlated with manual pathology data (r = 0.83 to 0.94). Measures were robust and reproducible across different magnifications and repeated scans. Digital measures for Aβ and tau-tangles across multiple brain regions reproduced established patterns of correlations, even when samples were stratified by clinical diagnosis. Finally, we harmonized newly generated digital measures with historical measures across multiple large autopsy-based studies. We describe a multidisciplinary approach to develop a digital pathology pipeline that reproducibly identifies AD neuropathologies, Aβ load, and tau-tangles. Digital pathology is a powerful tool that can overcome critical challenges associated with traditional microscopy methods.
Human leucocyte antigen (HLA)-C is expressed at lower levels than other classical HLA-I molecules on somatic cells. Surface HLA-C proteins can occur as conventionally β₂-microglobulin ...(β2m)-associated complexes or as open conformers dissociated from peptide and/or β₂m. We investigated the conformation of HLA-C molecules on normal human trophoblast cells, which invade the maternal decidua during placentation. A panel of monoclonal antibodies to different conformations of HLA-I molecules was used in flow cytometry and surface immunoprecipitation experiments. On the surface of trophoblast cells only β₂m-associated complexes of HLA-C molecules were detected. In contrast, both open conformers and β₂m-associated HLA-C could be detected on other cells from the decidua, HLA-C-transfectants and cell lines. The levels of HLA-C expressed on primary trophoblast cells could be detected by antibodies specific to non-β₂m-associated conformations because binding was seen after acid-induced denaturation of surface proteins. In contrast to HLA-G molecules on trophoblasts, we found no evidence for the presence of disulphide-linked multimers of HLA-C complexes. These results show that most HLA-C molecules present at the trophoblast cell surface are in the conventional β₂m-associated conformation. These findings have implications regarding the stability of trophoblast HLA-C molecules and how they interact with receptors on decidual leucocytes during placentation.
The aim of this study was to evaluate pretreatment clinical features and biological markers together with changes in these factors as predictors of response and relapse in patients receiving ...tamoxifen for primary breast cancer. Fine-needle aspiration cytology of the primary breast cancer was performed before tamoxifen treatment in 54 patients and repeated after therapy on day 14, day 60, or on both days in a subset of 35 patients. These samples were evaluated for estrogen receptor (ER), progesterone receptor (PgR), Ki67, S-phase fraction and ploidy. The overall response to tamoxifen was 57% (31 of 54 patients). Pretreatment ER and PgR significantly predicted for response by univariate analysis (P < 0.0001 and P < 0.003, respectively). By multivariate analysis, ER expression was the only independent predictor of response, and it was associated with 27 times the likelihood of response (95% confidence interval, 6-136). Increase in PgR and decrease in Ki67 on day 14 significantly predicted for response to tamoxifen (P < 0.03 and P < 0.04, respectively). Lack of ER, clinical node-positive disease, and failure to decrease Ki67 on day 14 were significantly associated with increased risk of relapse (P < 0.05). By multivariate analysis, ER expression was the only independent predictor of relapse (P < 0.005). Pretreatment and early changes in molecular marker expression may assist in the prediction of response and clinical outcome in primary breast cancer patients receiving tamoxifen.
Background
Allelic variation to the APOE gene confers the greatest genetic risk for sporadic Alzheimer’s disease (AD). Independent of genotype, low abundance of apolipoprotein E (apoE), is ...characteristic of AD CSF, and predicts cognitive decline. The mechanisms underlying the genotype and apoE level risks are uncertain. Recent fluid and imaging biomarker studies have revealed an unexpected link between apoE and brain iron, which also forecasts disease progression, possibly through ferroptosis, an iron‐dependent regulated cell death pathway.
Method
Ferroptosis was induced in the N27 neuronal cell model of ferroptosis using multiple agents (erastin, RSL3, iron, cysteine depletion). The severity of ferroptosis was measured by several toxicity assays (MTT, LDH) and lipid peroxide probe (C11BODIPY). Iron levels in the temporal inferior cortex was gathered from 608 deceased subjects in the memory and aging project (MAP, Chicago, USA). Iron levels were quantified and analyzed using multiple regression models stratified by APOE genotype.
Result
We report that apoE is a potent inhibitor of ferroptosis (EC50≈10 nM; N27 neurons). We demonstrate that apoE signals to activate the PI3K/AKT pathway that then inhibits the autophagic degradation of ferritin (ferritinophagy), thus averting iron‐dependent lipid peroxidation. Using postmortem inferior temporal brain cortex tissue from deceased subjects from the Rush Memory and Aging Project (MAP) (N = 608), we found that the association of iron with pathologically confirmed clinical Alzheimer’s disease was stronger among those with the adverse APOE‐ε4 allele. While protection against ferroptosis did not differ between apoE isoforms in vitro, other features of ε4 carriers, such as low abundance of apoE protein and higher levels of polyunsaturated fatty acids (which fuel ferroptosis) could mediate the ε4 allele’s heighted risk of AD.
Conclusion
We show that apoE protects against ferroptic neurodegeneration through regulating autophagy and identified an increased risk of AD diagnosis associated with the apoE risk allele in a clinical study. These findings support ferroptosis as a putative pathway to explain the major genetic risk associated with late onset AD.
Background
Iron is an essential trace metal for brain health but maybe damaging when in excess, for example, through the regulated cell death program, ferroptosis. We earlier reported that higher ...brain iron levels are associated with faster cognitive decline and more neurofibrillary tangles, but the cause of iron elevation is unknown. This study investigates dietary and demographic factors associated with brain iron levels, Alzheimer’s Disease (AD) pathology, and cognitive decline.
Method
The study was conducted in 614 decedents (age‐at‐death:91.2±7.2years; education:14.6±3years;70% females) of the Rush Memory and Aging Project. AD pathology was assessed using standard criteria. Brain iron levels were evaluated in four brain regions (inferior temporal, mid frontal, and anterior cingulate cortices, and cerebellum) using Inductively Coupled Plasma Mass Spectrophotometry, and a composite mean z‐score was generated. Cognitive performance measured with 19 tests examined annually until death. Mean annual dietary iron intake was obtained from a validated food frequency questionnaire. Linear and logistic regression models with stepwise selection were used to investigate associations.
Result
The mean dietary iron intake (up to>10 years of follow‐up before death) was not associated with postmortem brain iron levels, cognitive decline, or global AD pathology. Age‐at‐death (β=‐0.01,p=0.001), sex (β=0.30,p<0.0001), smoking (β=‐0.20,p=0.0008), and APOE‐ε 4 status (β=1.65,p=0.01) were each associated with higher brain iron levels. Except for APOE‐ε 4 status, these associations were retained when further controlled for AD pathology. Among dietary factors, in the age‐adjusted model, total fat (β=0.007,p=0.04) was positively, and omega‐3 fat (β=‐0.18,p=0.001) was negatively associated with higher brain iron levels. However, with further adjustment for age, sex, smoking, and APO‐ε 4 status, only the omega‐3 association, was retained.
Conclusion
Unlike brain iron, dietary iron intake does not relate to AD pathology or cognitive decline. This may not be surprising since the blood‐brain barrier is relatively impermeable to fluctuations in blood iron levels. Brain iron accumulation in older adults relates to demographic factors independent of AD pathology. Overall, brain iron was not associated with dietary iron but was inversely associated with omega‐3 fats. Further studies on fat intake, dietary fat and iron interaction, and its relationship with brain measures are warranted.
Abstract
Background
Copper (Cu) is an essential element for brain health. There is increasing recognition that altered Cu homeostasis is related to the development of Alzheimer’s disease (AD). ...Neuropathologic findings of amyloid plaque and neurofibrillary tangles are the hallmarks of Alzheimer's disease process. Whether brain Cu is associated with AD neuropathology in humans is unknown. This study examines the relationship between brain Cu levels and AD neuropathology in autopsies from a community sample of older adults.
Method
The study was conducted in 679 deceased participants from the Rush Memory and Aging Project, a cohort study. Brain Cu levels were measured using ICP‐MS in gray matter from inferior temporal, mid frontal, anterior cingulate, and cerebellum. Diffuse and neuritic plaques and neurofibrillary tangles were assessed in multiple brain regions and summarized as standard measures of AD pathology, including Braak, CERAD, NIA‐Reagan, global AD pathology. Linear regression analyses were used to evaluate the associations of brain Cu (grouped in tertiles) with the AD pathology in models controlled for age at death, sex, education, and APOE‐ ε 4 status.
Result
The mean age at death was 90.2 (±6.2) years, 70% were women, and 25% carriers of the APOE4 allele. Higher brain Cu levels were associated with less AD neuropathology. Participants in the middle and highest tertile of overall brain Cu levels had less global AD pathology (T3 vs. T1:β = ‐0.10; T2 vs. T1 = ‐0.11; p trend = 0.007) and Braak stage (T3 vs. T1: β = ‐0.31; T2 vs. T1 = ‐0.22; p trend = 0.005) when compared to those in the lowest tertile. Similar associations were found between inferior temporal brain Cu levels and AD neuropathology: global AD pathology (T3 vs. T1: β = ‐0.17, p = <0.0001); Braak (T3 vs. T1: β = ‐0.42, p = 0.0001); CERAD (T3 vs. T1: β = ‐0.17, p = 0.008); NIA‐Reagan (T3 vs. T1: β = ‐0.21, p = 0.002)). Brain Cu levels in mid‐frontal and cerebellum had a marginal association, whereas anterior cingulate Cu levels had no association with AD neuropathology.
Conclusion
Higher brain copper levels are associated with fewer AD neuropathology, suggesting that brain Cu levels either may reflect the severity of the disease or may indicate its potential beneficial effect on the disease process.
Background
Copper (Cu) is an essential element for brain health. There is increasing recognition that altered Cu homeostasis is related to the development of Alzheimer’s disease (AD). Neuropathologic ...findings of amyloid plaque and neurofibrillary tangles are the hallmarks of Alzheimer's disease process. Whether brain Cu is associated with AD neuropathology in humans is unknown. This study examines the relationship between brain Cu levels and AD neuropathology in autopsies from a community sample of older adults.
Method
The study was conducted in 679 deceased participants from the Rush Memory and Aging Project, a cohort study. Brain Cu levels were measured using ICP‐MS in gray matter from inferior temporal, mid frontal, anterior cingulate, and cerebellum. Diffuse and neuritic plaques and neurofibrillary tangles were assessed in multiple brain regions and summarized as standard measures of AD pathology, including Braak, CERAD, NIA‐Reagan, global AD pathology. Linear regression analyses were used to evaluate the associations of brain Cu (grouped in tertiles) with the AD pathology in models controlled for age at death, sex, education, and APOE‐ ε 4 status.
Result
The mean age at death was 90.2 (±6.2) years, 70% were women, and 25% carriers of the APOE4 allele. Higher brain Cu levels were associated with less AD neuropathology. Participants in the middle and highest tertile of overall brain Cu levels had less global AD pathology (T3 vs. T1:β = ‐0.10; T2 vs. T1 = ‐0.11; p trend = 0.007) and Braak stage (T3 vs. T1: β = ‐0.31; T2 vs. T1 = ‐0.22; p trend = 0.005) when compared to those in the lowest tertile. Similar associations were found between inferior temporal brain Cu levels and AD neuropathology: global AD pathology (T3 vs. T1: β = ‐0.17, p = <0.0001); Braak (T3 vs. T1: β = ‐0.42, p = 0.0001); CERAD (T3 vs. T1: β = ‐0.17, p = 0.008); NIA‐Reagan (T3 vs. T1: β = ‐0.21, p = 0.002)). Brain Cu levels in mid‐frontal and cerebellum had a marginal association, whereas anterior cingulate Cu levels had no association with AD neuropathology.
Conclusion
Higher brain copper levels are associated with fewer AD neuropathology, suggesting that brain Cu levels either may reflect the severity of the disease or may indicate its potential beneficial effect on the disease process.
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