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PubMed2000

Optimizing the use of biomarkers, surrogate endpoints, and clinical endpoints for more efficient drug development.

Biomarkers and surrogate endpoints are critical to the future of efficient drug development. Definitions, a conceptual model, and a conceptual framework for validating and bridging biomarkers to clinical endpoints are provided in this presentation. In addition, a few examples are provided to support the development concept. Poor correlation between a biomarker and its clinical endpoint may result from (1) poor measurement of one or both, (2) selection of an inappropriate biomarker, or, more important, (3) use of an inappropriate clinical endpoint. Pharmacokinetic/pharmacodynamic (PK/PD) modeling output can be no better than biomarkers or surrogate endpoints used for the modeling. As we increase our understanding of biomarkers, surrogate markers, and the mechanistic basis for the processes of interest, biomarker and surrogate endpoint predictive power will no longer be an issue and PK/PD modeling inputs and outputs will improve.

Biomarkers↗

PubMed2004

Validation of biomarkers for impact evaluation of aqueous industrial waste in mesocosms.

The use of exposure biomarkers in measuring the impact of aqueous waste holds promise because such tools have short response times, are flexible in use and may give an indication about the type of pollution. However, their ecological significance has not yet been demonstrated. It is necessary to validate these responses under controlled conditions before using such biomarkers for biomonitoring. The TotalFinaElf company has developed a pilot scheme incorporating such controlled conditions. This pilot is a dynamic open mesocosm (16 channels 40 m in length supplied with river water). The research programme currently carried out in the "Pilot Rivers" aims at validating biochemical parameters (components of phases I and II (de)toxication metabolism and propionylcholinesterase activity), measured in a fresh water bivalve Corbicula fluminea as a biomarker of water quality. The comparison between biomarker responses and community ones (reference) gives information about the precocity and sensitivity of these biomarker responses. Pure substances (trichloroethylene (TCE), cadmium (CD) and anthracenic oil (AO)) have been injected during one month. Biomarker responses are as sensitive as the most sensitive community response in the presence of CD and AO. With TCE, community responses are more sensitive. Precocity of biomarker response is observed only in the presence of CD.

Animals↗

PubMed2006

[The use of biomarkers in cancer prevention].

Biomarkers in cancer prevention are increasingly important tools in primary prevention and in intervention by chemopreventive agents. Biomarkers can be utilized as indicators of exposures, effects and individual susceptibility to cancer. Sampling of biomarkers in relation to exposure may have a great impact on the reliability of mechanism of action. The recent developments in genomics provides us with an opportunity to investigate simultaneously numerous oncogenes, tumor-suppressor genes, phenotypic changes in proteins and to utilize the same samples for better understanding of possible ways to disrupt carcinogenesis. Identification of high cancer risk biomarkers is possible also by traditional molecular genetics techniques. Chromosomal studies are based on peripheral blood lymphocyte (PBL) cultures, which may present mutation as a cytogenetic change on chromosome structures. International databases are available for evaluation of high cancer risk among those people who are carrying high incidence of chromosomal aberrations. The biomarkers are suitable to indicate the need for intervention in high risk groups. In those cases, where removal of environmental hazards are not efficient enough in preventive measures since genetic damages are irreversible, it may be possible to introduce chemoprevention at the same time, which includes changes in lifestyle, smoking and drinking habits as well as prescription of vitamins, antioxidants, minerals etc. This paper summarizes the current knowledge on biomarkers indicative of high risk groups and/or individual susceptibility measured by different methodologies, mainly based on Hungarian human genotoxic monitoring studies, which may help to understand the use of biomarkers in everyday medical practice.

Biomarkers, Tumor↗

PubMedDate not supplied

[Therapeutic and prognostic significance of cardiac biomarkers in patients with the acute coronary syndrome].

Diagnostics in patients with the acute coronary syndromes (ACS) is becoming even more complex with the increase of number of available options. In addition, the number of treatment options accessible to patients with ACS keeps on growing rapidly. Physicians must now choose from a wide variety of antiplatelet and antithrombotic therapies and also determine what patients would benefit from an invasive management approach. These decisions have become more difficult with the introduction of recent drugs such as low molecular weight heparins, direct-acting antithrombins, thienopyridines, and glycoprotein IIb/IIIa inhibitors. Simple tools, which can often be applied at the patient's bedside, can help physicians to choose the intensity of antiplatelet and antithrombotic therapy, and decide whether to use invasive coronary procedures. Cardiac biomarkers have proven to be particularly effective for these purposes. Moreover, cardiac biomarkers play an important role in risk stratification in ACS, and the results of cardiac biomarker tests can be used to help us choose between alternative therapies. In addition to biomarkers of myocyte necrosis, markers of neurohormonal activation, such as B-type natriuretic peptide (BNP), provide important prognostic information in ACS. However, the increase of number of elevated biomarkers, although simple to implement in practice, does not allow for full employment of value of information provided by these biomarkers. In the future, multimarker strategies that incorporate panels of cardiac biomarkers are likely to be used for risk stratification and for pathophysiology guided treatment in patients with ACS.

Angina, Unstable↗

PubMed2006

Current status of biomarkers for melanoma metastasis.

There is a critical unmet need for new predictive and prognostic biomarkers for melanoma. This feature presents a brief overview of the opportunities and challenges facing investigators who are seeking biomarkers that can predict those melanomas that are likely to result in progression (metastasis) and death. Melanoma metastasis to the regional lymph nodes is now readily identified by sentinel node biopsy. However, currently available prognostic factors, which are based on clinical parameters and histological findings in the primary tumor, are limited in their ability to reliably discriminate which patients will manifest sentinel node metastasis and/or disseminated disease. To date, even those biomarkers for which substantial clinical correlation has been obtained have suffered from both conflicting data in clinical trials involving different patient populations and poorly understood interactions between the biomarkers and other established prognostic factors. An understanding of whether biomarker data should be viewed as a continuum or be categorized based on discrete breakpoints is also frequently lacking. In many cases, biomarkers are initially developed based on unequivocal index cases, such as clearly benign or clearly malignant melanocytic lesions, but then fail as predictive tools when applied to the more difficult cases that arise in clinical practice; such cases occupy a 'gray' zone that is filled with uncertainty and lacks an established 'gold standard' against which a biomarker prediction can be validated.

Animals↗

PubMed1996

Variability of molecular biomarker measurements from nonlinear calibration curves.

In any immunoassay experiment for the detection of molecular biomarkers, a nonlinear calibration curve is constructed to relate fixed biomarker concentrations to observed tracer levels. The biomarker concentration in an experimental sample can then be estimated by projecting the experimental tracer measurements through the inverse of the calibration curve. Once an estimate of the biomarker level has been calculated, it is often of interest to determine its variability. Typically, methods for estimating this variability assume that the biomarker variability is due solely to the uncertainty in the estimation of the calibration curve. A more complete analysis would combine this uncertainty with the variability in the processing and measurements of the sample, including, e.g., measurement error of laboratory procedures or variation in enzymatic activity in enzyme-linked immunosorbent assays or radioactivity counts in RIAs. In this paper, we present a method of estimating the variability of inverse estimates assuming there is variation arising from both the determination of the calibration curve and from the preparation and measurement of the experimental sample. Our method uses a resampling algorithm that avoids requiring many distributional assumptions present in alternative procedures, can be easily implemented, and is generalizable to any immunoassay procedure. Methods for incorporating our results in the estimation of variability for planning and analyzing biomarker experiments are discussed. We provide an example using RIA data for aflatoxin B1 detection. These biomarkers for aflatoxin exposure are used in the analysis of serum aflatoxin adduct levels in human and experimental samples, and they are important in hepatocellular carcinoma research.

Algorithms↗

PubMed2002

Pharmacogenomic biomarkers.

Pharmacogenomic biomarkers hold great promise for the future of medicine and have been touted as a means to personalize prescriptions. Genetic biomarkers for disease susceptibility including both Mendelian and complex disease promise to result in improved understanding of the pathophysiology of disease, identification of new potential therapeutic targets, and improved molecular classification of disease. However essential to fulfilling the promise of individualized therapeutic intervention is the identification of drug activity biomarkers that stratify individuals based on likely response to a particular therapeutic, both positive response, efficacy, and negative response, development of side effect or toxicity. Prior to the widespread clinical application of a genetic biomarker multiple scientific studies must be completed to identify the genetic variants and delineate their functional significance in the pathophysiology of a carefully defined phenotype. The applicability of the genetic biomarker in the human population must then be verified through both retrospective studies utilizing stored or clinical trial samples, and through clinical trials prospectively stratifying patients based on the biomarker. The risk conferred by the polymorphism and the applicability in the general population must be clearly understood. Thus, the development and widespread application of a pharmacogenomic biomarker is an involved process and for most disease states we are just at the beginning of the journey towards individualized therapy and improved clinical outcome.

Drug Design↗

PubMed2024

Free-water: A promising structural biomarker for cognitive decline in aging and mild cognitive impairment.

Diffusion MRI derived free-water (FW) metrics show promise in predicting cognitive impairment and decline in aging and Alzheimer's disease (AD). FW is sensitive to subtle changes in brain microstructure, so it is possible these measures may be more sensitive than traditional structural neuroimaging biomarkers. In this study, we examined the associations among FW metrics (measured in the hippocampus and two AD signature meta-ROIs) with cognitive performance, and compared FW findings to those from more traditional neuroimaging biomarkers of AD. We leveraged data from a longitudinal cohort (nparticipants = 296, nobservations = 870, age at baseline: 73 ± 7 years, 40% mild cognitive impairment [MCI]) of older adults who underwent serial neuropsychological assessment (episodic memory, information processing speed, executive function, language, and visuospatial skills) and brain MRI over a maximum of four time points, including baseline (n = 284), 18-month (n = 246), 3-year (n = 215), and 5-year (n = 125) visits. The mean follow-up period was 2.8 ± 1.3 years. Structural MRI was used to quantify hippocampal volume, in addition to Schwarz and McEvoy AD Signatures. FW and FW-corrected fractional anisotropy (FAFWcorr) were quantified in the hippocampus (hippocampal FW) and the AD signature areas (SchwarzFW, McEvoyFW) from diffusion-weighted (dMRI) images using bi-tensor modeling (FW elimination and mapping method). Linear regression assessed the association of each biomarker with baseline cognitive performance. Additionally, linear mixed-effects regression assessed the association between baseline biomarker values and longitudinal cognitive performance. A subsequent competitive model analysis was conducted on both baseline and longitudinal data to determine how much additional variance in cognitive performance was explained by each biomarker compared to the covariate only model, which included age, sex, race/ethnicity, apolipoprotein-ε4 status, cognitive status, and modified Framingham Stroke Risk Profile scores. All analyses were corrected for multiple comparisons using an FDR procedure. Cross-sectional results indicate that hippocampal volume, hippocampal FW, Schwarz and McEvoy AD Signatures, and the SchwarzFW and McEvoyFW metrics are all significantly associated with memory performance. Baseline competitive model analyses showed that the McEvoy AD Signature and SchwarzFW explain the most unique variance beyond covariates for memory (ΔRadj 2 = 3.47 ± 1.65%) and executive function (ΔRadj 2 = 2.43 ± 1.63%), respectively. Longitudinal models revealed that hippocampal FW explained substantial unique variance for memory performance (ΔRadj 2 = 8.13 ± 1.25%), and outperformed all other biomarkers examined in predicting memory decline (pFDR = 1.95 x 10-11). This study shows that hippocampal FW is a sensitive biomarker for cognitive impairment and decline, and provides strong evidence for further exploration of this measure in aging and AD.

Alzheimer’s disease (AD)↗

PubMed1999

The biomarkers detecting early changes in the human organism exposed to occupational carcinogens.

Epidemiological studies and clinical data confirm that occupational exposure to carcinogenic agents plays an important role in cancer etiology. Recent tremendous progress in understanding of the mechanisms of carcinogenesis, and also introduction of new tests to recognize changes occurring in the exposed organism have made it possible for the occupational medicine to detect the earliest cancer stages which occur during the latent phase of the disease. Detecting pre-neoplastic changes which precede an overt form of cancer and identification of measurable indicators of those changes has been one of the fundamental aims of molecular biology research. Biomarkers may serve as a research tool which makes it possible to achieve this aim. Suitably selected biomarker sets can provide information on the extent of the exposure to carcinogenic agents (biomarkers of exposure), detect early changes produced by the agents in the exposed organism (biomarkers of effects), and identify people with particularly high cancer risk (biomarkers of susceptibility). It will soon be possible to use molecular biomarkers, capable of detecting increased cancer risk at the molecular level of cell structure, in prophylactic action intended to reduce cancer incidence. Molecular biomarkers are capable of recording very early health effects of exposure to carcinogens, thus making it possible to determine cancer risk at a very early stage of cancer development.

Carcinogens, Environmental↗

PubMed2005

Can we develop biomarkers that predict response of cancer patients to immunotherapy?

PRIMARY OBJECTIVE: The primary objective is to delineate the potential utility of cancer biomarkers that correlate and predict response to immunotherapy in cancer patients who are refractory to conventional therapeutics. Unlike significant development of biomarkers that predict response to chemotherapy, very few biomarkers have been developed to predict the response to immunotherapy. MAIN OUTCOMES AND RESULTS: This article describes briefly the importance of characterizing and validating biomarkers for immunotherapy. A few examples have been provided, such as the transcription factor NF-kappaB, the transcription repressor Yin-Yang 1 (YY1), the pro-apoptotic gene product (Smac/DIABLO) and the circulating Fas and Fas ligand. These biomarkers have been determined to be of prognostic significance in different cancers. CONCLUSIONS: Immunotherapy is considered as an alternative therapy in the treatment of cancer patients who are refractory to chemotherapy/radiation/hormonal therapies. Cross-resistance to apoptosis develops between cancer cells that are resistant to conventional therapeutics and immunotherapy. Therefore, it is important to develop biomarkers that will determine patient response to immunotherapy.

Animals↗

PubMed2000

Proteomic strategies for biomarker identification: progress and challenges.

The simplest definition of a biomarker is a molecule that indicates an alteration in physiology from normal. A more practical definition of a biomarker would require clinical utility of this molecule. In this sense, the biomarker would specifically and sensitively reflect a disease state and could be used for diagnosis as well as for disease monitoring during and following therapy. The need for such biomarkers in all clinical fields is urgent, since the current arsenal of biomarkers is sadly deficient and, in most cases, non-specific. In this review, we discuss strategies that use a proteomics approach to identify novel biomarkers and give examples of recent studies employing these strategies.

Animals↗

PubMed2006

Association of physical activity and body mass index with novel and traditional cardiovascular biomarkers in women.

CONTEXT: There are few data directly comparing the effects of physical activity and body weight on cardiovascular biomarkers. OBJECTIVE: To examine the association of physical activity and body mass index (BMI, defined as weight in kilograms divided by the square of height in meters) alone and in combination with cardiovascular biomarkers. DESIGN, SETTING, AND PARTICIPANTS: Cross-sectional analysis of 27,158 apparently healthy US women (mean age, 54.7 years) at the time of enrollment (1992-1995) in the Women's Health Study, a randomized, double-blind, placebo-controlled trial of low-dose aspirin and vitamin E in the primary prevention of cardiovascular disease and cancer. MAIN OUTCOME MEASURES: The association of physical activity and BMI with high-sensitivity C-reactive protein (CRP), fibrinogen, soluble intracellular adhesion molecule 1 (ICAM-1), homocysteine, low- and high-density lipoprotein (LDL and HDL) cholesterol, total cholesterol, apolipoprotein A-1 and B100, lipoprotein(a), and creatinine. RESULTS: Lower levels of physical activity and higher levels of BMI were independently associated (P for trend <.001) with adverse levels of nearly all lipid and inflammatory biomarkers. High BMI showed stronger associations with these biomarkers than physical inactivity. For example, using the reference group of physically active, normal weight women (energy expenditure > or =1000 kcal/week; BMI, 18.5-24.9) and adjusting for age, race, smoking, blood pressure, diabetes, menopausal status, and hormone use, the odds ratios (95% confidence intervals [CIs]) for having CRP >3 mg/L were: for inactive, normal weight women 1.26 (1.15-1.37); active, overweight 2.68 (2.41-2.98); inactive, overweight 3.11 (2.84-3.41); active, obese 8.25 (7.15-9.51); and inactive, obese 9.86 (8.84-10.99). In similar analyses, the odds ratios (95% CIs) for having HDL cholesterol <50 mg/dL were 1.20 (1.11-1.30); 2.25 (2.04-2.49); 2.62 (2.41-2.85); 4.21 (3.68-4.81); and 5.27 (4.77-5.84), respectively, and for having apolipoprotein B100 >120 mg/dL they were 1.21 (1.11-1.33); 1.86 (1.66-2.08); 2.06 (1.88-2.67); 2.35 (2.04-2.70); and 2.33 (2.09-2.59). Fibrinogen, ICAM-1, apolipoprotein A1, total cholesterol, and LDL cholesterol showed similar associations. By contrast, homocysteine, lipoprotein (a), and creatinine showed weak or nonsignificant associations. CONCLUSIONS: High BMI was more strongly related to adverse cardiovascular biomarker levels than physical inactivity. However, within BMI categories, physical activity was generally associated with more favorable cardiovascular biomarker levels than inactivity.

Biomarkers↗

PubMed2000

Potential roles of genetic biomarkers in colorectal cancer chemoprevention.

Colorectal cancer is a significant cause of morbidity and mortality in industrialized societies and the second most frequent cause of cancer death in the United States. Surrogate endpoint biomarkers are gaining wide acceptance in early diagnosis and short-term cancer chemoprevention trials in place of cancer endpoints. Molecular genetic biomarkers can be useful tools in identifying subjects at risk of developing cancer and screening for early cancers amenable to complete cure. They may be useful both in predicting and assessing response to a given therapy and in determining prognosis after an initial diagnosis has been made. Ideally, biomarkers should fulfill some, if not all, of the following criteria: variability of expression between phases of carcinogenesis, association with cancer risk, ability to undergo modification in response to a chemopreventive agent, and finally, permit ease of measurement. In consideration of colorectal cancer chemoprevention, several genetic biomarkers seem to meet many of these criteria, as they do exhibit distinct variability of expression at different phases of carcinogenesis, are often strongly associated with increased cancer risk (especially the hereditary/familial syndromes), are generally able to be measured relatively easily through peripheral blood sampling (germline mutations) or by colonic mucosal sampling by endoscopic techniques (somatic mutations). In some cases, genetic biomarkers have also been demonstrated to undergo modification in response to a chemopreventive agent. With further understanding of the genetic and molecular changes involved in sporadic and familial colorectal carcinogenesis, genetic biomarkers appear to hold great potential for the identification of subjects at high risk of developing colorectal cancer, as well as the development of novel chemopreventive approaches and form a promising area for further research.

Anticarcinogenic Agents↗

PubMed1990

The use of biomarkers in the prediction of survival in patients with pulmonary carcinoma.

Data on ten variables and 16 biomarkers were obtained on 119 patients with newly diagnosed pulmonary cancer. The prognostic value of 16 biomarkers (alpha-1-antitrypsin [AAT], adrenocorticotropic hormone [ACTH], alpha-fetoprotein [AFP], carcinoembryonic antigen [CEA], human chorionic gonadotropin [HCG], immune complexes, immunoglobulins, N-terminal peptide of proopiomelanocortin [NTERM], and tumor-associated antibody [TAA]) was tested by adding these to the model of age, gender, stage, morphology, Feinstein's classification of symptoms, Karnofsky scale, leukocyte count, recent weight loss, and liver enzymes. Using Cox's regression method and a forward stepwise procedure, seven biomarkers (ACTH, AAT, AFP, calcitonin, HCG, TAA, and prolactin) entered the model. Elevated levels of cortisol and TAA were associated with longer survival. The selection of biomarkers by stepwise regression needs to be interpreted with caution, especially since the Z scores were found to be dependent on the particular variables included in the model. Furthermore, when dichotomized on maximum of the normal laboratory values, HCG and AFP were infrequently (2%) elevated. The lack of correlation among the biomarkers supports the hypothesis of random derepression of the genome of cancer cells. Further studies in improved modeling and the formulation of a biomarker index could enhance our understanding of the biology of cancer.

Adenocarcinoma↗

PubMed2001

Proteomic approaches to biomarker discovery in prostate and bladder cancers.

Proteomic technologies, including high resolution two-dimensional electrophoresis (2-DE), antibody/protein arrays, and advances in mass spectrometry (MS), are providing the tools needed to discover and identify disease associated biomarkers. Although application of these technologies to search for potential diagnostic/prognostic biomarkers associated with prostate and bladder cancer have been somewhat limited to date, proteins either overexpressed or underexpressed have been detected in both these urological cancers. Recent advances in mass spectrometry, especially platforms that permit rapid "fingerprint" profiling of multiple biomarkers, and tandem mass spectrometers for protein identification, will most assuredly enhance the discovery, identification, and characterization of potential cancer associated biomarkers. Furthermore, application of laser capture microdissection microscopes has provided a rapid and reproducible approach to procure pure populations of cells. This technology coupled to 2-DE and MS has significantly aided the elucidation of the differential expression profiles between disease, benign and normal prostate and bladder cell populations. Finally, development and application of learning algorithms and bioinformatics to the data generated by these proteomic technologies will be essential in determining the clinical potential of a protein biomarker. The purpose of this review is to provide the reader with an overview of the application of these technologies in the search and identification of potential diagnostic/prognostic biomarkers for prostate and bladder cancers.

Biomarkers, Tumor↗

PubMed2026

Translational Gap in Biomarker Discovery: Tumor Surface Markers Rarely Mirror Circulating Levels.

BACKGROUND: Tumor-associated cell surface proteins are frequently proposed as circulating biomarkers for colorectal cancer (CRC) based on their high tumor expression. However, many candidates identified through tissue-based analyses fail to translate into clinically useful biomarkers. We investigated the translational gap between tissue-level expression and circulating detectability in CRC, focusing on molecular subtypes defined by caudal-type homeobox 2 (CDX2) expression. METHODS: Transcriptomic data from The Cancer Genome Atlas (TCGA) were analyzed to identify cell surface markers differentially expressed between CDX2-Low and CDX2-High CRCs. A clinical cohort of right-sided CRC patients was evaluated using paired tumor tissue and preoperative plasma samples. CDX2 expression was assessed by immunohistochemistry, and circulating concentrations of selected cell surface proteins were quantified using a multiplex ELISA platform. RESULTS: Several tumor-associated cell surface markers exhibited marked CDX2-dependent differences in tissue expression. However, for most markers, circulating plasma levels did not mirror tissue-level patterns. CEACAM1 was the sole marker demonstrating concordant CDX2-dependent differences in both tumor tissue and plasma, with significantly lower levels in CDX2-Low CRCs. In contrast, CEACAM5 showed a dissociation between tissue expression and circulating levels, despite analytical validation against serum carcinoembryonic antigen (CEA). CONCLUSIONS: Our findings demonstrate that tumor overexpression of cell surface markers does not necessarily translate into detectable circulating biomarkers. This translational disconnect underscores limitations of biomarker selection strategies based solely on tissue expression and highlights the importance of integrating systemic biology into biomarker development. While some tumor-associated proteins may lack utility as circulating biomarkers, they may still represent viable therapeutic targets in CRC.

CDX2↗

PubMed2002

Molecular indicators (biomarkers) of past life.

Biomarkers in geological samples on Earth are products derived from biochemical precursors (i.e., natural products) by reductive and oxidative alteration processes (e.g., cholestanes from cholesterol). Generally, lipids, pigments, and some biomembranes are preserved best over longer geological times, and labile compounds such as amino acids, sugars, etc. are useful biomarkers for recent times. Thus, the detailed characterization of biomarker composition permits the assessment of the major contributing species of extinct and/or extant life. Nonbiomarkers and abiogenic organic compounds are also discussed. In the case of the early Earth, work has progressed to elucidate biomarker structures and carbon isotopic signals preserved in ancient sedimentary rocks. In addition, the combination of bacterial biochemistry with the organic geochemistry of contemporary and ancient hydrothermal ecosystems permits the modeling of the nature, behavior, and preservation potential of primitive microbial communities. This approach entails combined molecular and isotopic analyses to characterize lipids and biopolymers produced by cultured bacteria (representative of ancient strains) and to test a variety of culture conditions that affect their biosynthesis processes. In regards to Mars, the biomarkers from lipids and biopolymers would be expected to be preserved best if life flourished there during its early history (3.5-4 x 10(9) years ago). Both oxidized and reduced products would be expected. This is based on the inference that hydrothermal activity occurred during that time, with the concomitant preservation of biochemically-derived carbonaceous matter. Known biomarkers (i.e., as elucidated for early terrestrial samples and for primitive terrestrial microbiota) as well as novel, potentially unknown compounds, should be characterized.

Bacterial Physiological Phenomena↗

PubMed2005

Pilot study on the impact of potato chips consumption on biomarkers of acrylamide exposure.

Food is assumed to be one major source of acrylamide exposure in the general population. Acrylamide exposure is usually assessed by measuring hemoglobin adducts of acrylamide and its primary metabolite glycidamide as biomarkers. Little is known about the impact of acrylamide in food on biomarkers of acrylamide exposure. Therefore, CDC is conducting a feeding study to investigate the effect of consumption of endogenous acrylamide in food on biomarkers of acrylamide exposure. As part of this study, we performed a pilot study to obtain further information on the magnitude of the changes in biomarker levels after consumption of high amounts of potato chips (21 ounces) over a short period of time (1 week) in non-smokers. After 1 week, biomarkers levels increased up to 46% for acrylamide adducts and 79% for glycidamide adducts. The results indicate that changes in biomarker levels due to consumption of potato chips can be detected. However, because of the design of this pilot study, the observed magnitude of change cannot be. generalized and needs to be confirmed in the main study.

Acrylamide↗