Based on the Ontology for General Medical Science, we propose definitions for biomarkers of various types of. These definitions provide not only a complete formal representation of what biomarkers are according to the Institute of Medicine (IOM), but also remove the ambiguities and inconsistencies encountered in the documentation provided by the IOM.

Prevention of age-related disorders is increasingly in focus of health policies, and it is hoped that early intervention on processes of deterioration can promote healthier and longer lives. New opportunities to slow down the aging process are emerging with new fields such as personalized nutrition. Data-intensive research has the potential to improve the precision of existing risk factors, e.g., to replace coarse-grained markers such as blood cholesterol with more detailed multivariate biomarkers. In this paper, we follow an attempt to (...) develop a new aging biomarker. The vision among the project consortium, comprising both research and industrial partners, is that the new biomarker will be predictive of a range of age-related conditions, which may be preventable through personalized nutrition. We combine philosophical analysis and ethnographic fieldwork to explore the possibilities and challenges of managing aging through bodily signs that are not straightforwardly linked to symptomatic disease. We document how the improvement of measurement brings about new conceptual challenges of demarcating healthy and unhealthy states. Moreover, we highlight that the reframing of aging as risk has social and ethical implications, as it is generative of normative notions of what constitutes successful aging and good citizenship. (shrink)

Thousands of candidate cancer biomarkers have been proposed, but so far, few are used in cancer screening. Failure to implement these biomarkers is attributed to technical and design flaws in the discovery and validation phases, but a major obstacle stems from cancer biology itself. Oncogenomics has revealed broad genetic heterogeneity among tumors of the same histology and same tissue (or organ) from different patients, while tumors of different tissue origins also share common genetic mutations. Moreover, there is wide (...) intratumor genetic heterogeneity among cells within any single neoplasm. These findings seriously limit the prospects of finding a single biomarker with high specificity for early cancer detection. Current research focuses on developing biomarker panels, with data assessment by machine‐learning algorithms. Whether such approaches will overcome the inherent limitations posed by tumor biology and lead to tests with true clinical value remains to be seen. (shrink)

In biomedical measurement, biomarkers are used to achieve reliable prediction of, and useful causal information about patient outcomes while minimizing complexity of measurement, resources, and invasiveness. A biomarker is an assayable metric that discloses the status of a biological process of interest, be it normative, pathophysiological, or in response to intervention. The greatest utility from biomarkers comes from their ability to help clinicians (and researchers) make and evaluate clinical decisions. In this paper we discuss a specific methodological use (...) of clinical biomarkers in pharmacological measurement: Some biomarkers, called ‘surrogate markers’, are used to substitute for a clinically meaningful endpoint corresponding to events and their penultimate risk factors. We confront the reliability of clinical biomarkers that are used to gather information about clinically meaningful endpoints. Our aim is to present a systematic methodology for assessing the reliability of multiple surrogate markers (and biomarkers in general). To do this we draw upon the robustness analysis literature in the philosophy of science and the empirical use of clinical biomarkers. After introducing robustness analysis we present two problems with biomarkers in relation to reliability. Next, we propose an intervention-based robustness methodology for organizing the reliability of biomarkers in general. We propose three relevant conditions for a robust methodology for biomarkers: (R1) Intervention-based demonstration of partial independence of modes: In biomarkers partial independence can be demonstrated through exogenous interventions that modify a process some number of “steps” removed from each of the markers. (R2) Comparison of diverging and converging results across biomarkers: By systematically comparing partially-independent biomarkers we can track under what conditions markers fail to converge in results, and under which conditions they successfully converge. (R3) Information within the context of theory: Through a systematic cross-comparison of the markers we can make causal conclusions as well as eliminate competing theories. We apply our robust methodology to currently developing Alzheimer’s research to show its usefulness for making causal conclusions. (shrink)

Central and peripheral biomarkers can be used to diagnose, treat, and potentially prevent major psychiatric disorders. But there is uncertainty about the role of these biological signatures in neural pathophysiology, and their clinical significance has yet to be firmly established. Psychomotor, cognitive, affective, and volitional impairment in these disorders results from the interaction between neural, immune, endocrine, and enteric systems, which in turn are influenced by a person’s interaction with the environment. Biomarkers may be a critical component of (...) this process. The identification and interpretation of biomarkers also raise ethical and social questions. This article analyzes and discusses these aspects of biomarkers and how advances in biomarker research could contribute to personalized psychiatry that could prevent or mitigate the effects of these disorders. (shrink)

In this round table response, we discuss some of the problems inherent in insisting on specific consent for an activity that needs to happen rapidly as part of a package of care. The Human Tissue Authority consider that specific consent is mandatory to assess which antibiotics are appropriate on the neonatal unit, but this insistence may actually limit the autonomy which consent aims to promote. While genetic testing to determine which child will react adversely to particular antibiotics has been available (...) clinically for several years, the research proposed here is to assess whether improving the speed of testing allows decisions to be made before treatment starts. Insisting on specific consent before this activity can take place is likely to delay appropriate care in some cases. On admission to the neonatal unit, the unwell infant is routinely subjected to a range of investigations and treatments. A person with parental responsibility will usually be asked to provide consent to undertake treatments for children who do not have capacity to give consent themselves.1 For the acutely unwell child, consent will usually be sought for a package of care: the urgent nature of neonatal medicine often requires clinicians to make many decisions without explicit consent. Doctors must always act in a child’s best interests: their decisions need to protect the health and well-being of a child and hold the child’s welfare paramount in accordance with the Children Act and General Medical Council guidelines.1 2 Thus, for example, ventilation might be initiated, sedation provided, antibiotics commenced or diagnostic investigations requested without separate consent conversations or …. (shrink)

Until recently, cardiotoxicity in the setting of a malignant disease was attributed solely to the detrimental effects of chemo‐ and/or radio‐therapy to the heart. On this account, the focus was on the evaluation of well‐established cardiac biomarkers for the early detection of myocardial damage. Currently, this view has been revised. Cardiotoxicity is not restricted to a single organ but instead affects the endothelium as a whole. Indeed, it has come into light that not only cancer therapy but also malignant (...) cells per se can impair the cardiovascular system, through a paracrine and endocrine mode of action. Even more intriguingly, a clear interplay between molecular pathways involved in cancer and cardiovascular disease has become prevalent, suggesting a common nominator that governs the pathophysiology of these two entities. Taken together, our strategy in the quest of novel biomarkers in the emerging field of cardio‐oncology should be critically reshaped. (shrink)

Validation of a biomarker-based medical product development tool or clinical test is an evidentiary process that must be tailored to the proposed use. Appropriate data and analyses are needed to demonstrate that the biomarker meets analytical and clinical performance criteria consistent with favorable benefit: risk balance.

Several previous studies have reported atypicality in resting-state functional connectivity in autism spectrum disorder, yet the relatively small effect sizes prevent us from using these characteristics for diagnostic purposes. Here, canonical correlation analysis and hierarchical clustering were used to partition the high-functioning ASD group into subgroups. A support vector machine model was trained through the 10-fold strategy to predict Autism Diagnostic Observation Schedule scores within the ASD discovery group, which was further validated in an independent sample. The neuroimage-based partition derived (...) two subgroups representing severe versus mild autistic patients. We identified FCs that show graded changes in strength from ASD-severe, through ASD-mild, to controls, while the same pattern cannot be observed in partitions based on ADOS score. We also identified FCs that are specific for ASD-mild, similar to a partition based on ADOS score. The current study provided multiple pieces of evidence with replication to show that resting-state functional magnetic resonance imaging FCs could serve as neural biomarkers in partitioning high-functioning autistic individuals based on their symptom severity and showing advantages over traditional partition based on ADOS score. Our results also indicate a compensatory role for a frontocortical network in patients with mild ASD, indicating potential targets for future clinical treatments. (shrink)

Graphical AbstractIs a two-fold approach — preliminary studies based on small samples followed by a large-sample study to check reproducibility — in the search for biomarkers really prudent?

Current research in molecular epidemiology uses biomarkers to model the different disease phases from environmental exposure, to early clinical changes, to development of disease. The hope is to get a better understanding of the causal impact of a number of pollutants and chemicals on several diseases, including cancer and allergies. In a recent paper Russo and Williamson address the question of what evidential elements enter the conceptualisation and modelling stages of this type of biomarkers research. Recent research in (...) causality has examined Ned Hall’s distinction between two concepts of causality: production and dependence. In another recent paper, Illari examined the relatively under-explored production approach to causality, arguing that at least one job of an account of causal production is to illuminate our inferential practices concerning causal linking. Illari argued that an informational account solves existing problems with traditional accounts. This paper follows up this previous work by investigating the nature of the causal links established in biomarkers research. We argue that traditional accounts of productive causality are unable to provide a sensible account of the nature of the causal link in biomarkers research, while an informational account is very promising. (shrink)

Surrogate endpoints are a common application of biomarkers to estimate clinical benefit in clinical trials, despite questions about reliability. This article discusses ongoing opportunities for their validation, in the context of a regulatory environment in which they are increasingly championed.

There is a burgeoning scientific and ethical literature on the use of biomarkers—such as genes or brain scan results—and biological interventions to predict and prevent crime. This literature on biopredicting and biopreventing crime focuses almost exclusively on crimes that are physical, violent, and/or sexual in nature—often called blue-collar crimes—while giving little attention to less conventional crimes such as economic and environmental offences, also known as white-collar crimes. We argue here that this skewed focus is unjustified: white-collar crime is likely (...) far costlier than blue-collar crime in money, health, and lives lost. Moreover, attempts to biopredict and bioprevent blue-collar crime may entail adopting potentially unfair measures that target individuals who are already socio-economically disadvantaged, thus compounding pre-existing unfairness. We argue, therefore, that we ought to extend the study of bioprediction and bioprevention to white-collar crime as a means of more efficiently and fairly responding to crime. We suggest that identifying biomarkers for certain psychopathic traits, which appear to be over-represented among senior positions in corporate and perhaps political organisations, is one avenue through which this research can be broadened to include white-collar crime. (shrink)

Understanding the phenomenon of health is crucial for ageing research since there is often an implicit view on what constitutes health and how to measure it. We provide some reflections on how we might better understand and measure health, discuss the basic biological principles of survival, ageing, age-related diseases and eventual death, and end by tying these ideas together to rethink the nature of and implications for healthy ageing. We defend a more positive view on health understood in terms of (...) various phenotypic parameters, such as robustness and resilience, and show how it relates to the aim to support these parameters over time to achieve healthy ageing. Together, these ideas suggest that the most effective strategies for healthy ageing may come from the outside-in by altering those aspects of the environment that prevent robust and resilient phenotypic responses and by supporting those aspects which ensure such responses. (shrink)

Biomarkers can be powerful tools to guide diagnosis, treatment, and research. However, prudent use of biomarkers requires formal validation efforts. Although the data needed for biomarker validation has traditionally been hard to access, new research initiatives can ease this process.

What is the value of an early diagnosis of dementia in the absence of effective treatment? There has been a lively scholarly debate over this question, but until now patients have not played a large role in it. Our study supplements biomedical research into innovative diagnostics with an exlporation of its meanings and values according to patients. Based on seven focusgroups with patients and their care-givers, we conclude that stakeholders evaluate early diagnostics with respect to whether and how they expect (...) it to empower their capacity to care. They value it, for instance, with respect to whether it explains experienced complaints, allows to start a process of psychological acceptance and social adaptation to the expected degeneration, contributes to dealing with anxieties, informs adequately about when to start preparing for the end of life, informs the planning of a request for euthanasia, or allows society to deal with a growing amount of dementia patients. Our study suggests that information about disease is considered ‘harmful’ or ‘premature’ when recipients feel unable to act on that information in their care. The results of this research offers input to further ethical research. It invites to adopt a care perspective in evaluation and to seek ways to prevent the ‘harm’ that such diagnostic methods can bring about. (shrink)

Cancer is fast becoming an alarming cause of human death. However, it has been reported that if the disease is detected at an early stage, diagnosed, treated appropriately, the patient has better chances of survival long life. Machine learning technique with feature-selection contributes greatly to the detecting of cancer, because an efficient feature-selection method can remove redundant features. In this paper, a Fuzzy Preference-Based Rough Set (FPRS) blended with Support Vector Machine (SVM) has been applied in order to predict cancer (...) biomarkers for biological and gene expression datasets. Biomarkers are determined by deploying three models of FPRS, namely, Fuzzy Upward Consistency (FUC), Fuzzy Downward Consistency (FLC), and Fuzzy Global Consistency (FGC). The efficiency of the three models with SVM on five datasets is exhibited, and the biomarkers that have been identified from FUC models have been reported. (shrink)

It has been argued that a biomarker-informed classification system for antisocial individuals has the potential to overcome many obstacles in current conceptualizations of forensic and psychiatric constructs and promises better targeted treatments. However, some have expressed ethical worries about the social impact of the use of biological information for classification. Many have discussed the ethical and legal issues related to possibilities of using biomarkers for predicting antisocial behaviour. We argue that prediction should not raise the most pressing ethical worries. (...) Instead, issues connected with ‘biologisation’, such as stigmatization and negative effects on self-image, need more consideration. However, we conclude that also in this respect there are no principled ethical objections against the use of biomarkers to guide classification and treatment of adult antisocial individuals. (shrink)

An increasing number of people seek medical attention for mild cognitive symptoms at older age, worried that they might develop Alzheimer’s disease. Some clinical practice guidelines suggest offering biomarker testing in such cases, using a brain scan or a lumbar puncture, to improve diagnostic certainty about Alzheimer’s disease and enable an earlier diagnosis. Critics, on the other hand, point out that there is no effective Alzheimer treatment available and argue that biomarker tests lack clinical validity. The debate on the ethical (...) desirability of biomarker testing is currently polarized; advocates and opponents tend to focus on their own line of arguments. In this paper, we show how the method of reflective equilibrium can be used to systematically weigh the relevant arguments on both sides of the debate to decide whether to offer Alzheimer biomarker testing. In the tradition of RE, we reflect upon these arguments in light of their coherence with other argumentative elements, including relevant facts, ethical principles, and theories on societal ideals or relevant concepts, such as autonomy. Our stance in the debate therefore rests upon previously set out in-depth arguments and reflects a wide societal perspective. (shrink)

“Additional needs children” is a term often used in the education system to describe children with school-based problems characterised by learning difficulties arising from academic, social and emotional stressors including, but not limited to, clinically diagnosed Neurodevelopmental Disorders (NDD). What has seldom been investigated is what biopsychosocial characteristics and other common comorbid behaviours are associated with academic learning difficulties. Thus, the aim of this study was to investigate the relationship between anxiety levels (Spence Children’s Anxiety Scale- Parent Report), autism traits (...) (Autism Spectrum Quotient – Child Version) and sleep quality (Sleep Disturbance Scale for Children) in ‘additional needs children’ with a diagnosis of Autism Spectrum Disorder (ASD), Language Impairment or Mixed Diagnosis without an intellectual disability. The results demonstrated that the ASD group reported more impairments associated with comorbid anxiety and sleep compared to the other clinically diagnosed groups. Similarly, greater anxiety level was positively associated with a greater number of autism traits and poorer sleep quality regardless of diagnostic group. This suggests that higher anxiety symptoms are a core biomarker of children who often first come to their teacher’s attention with reading and learning difficulties (i.e. “additional needs”), irrespective of the primary cause of school-based problems. (shrink)

Biomarkers are widely used not only as prognostic or diagnostic indicators, or as surrogate markers of disease in clinical trials, but also to formulate theories of pathogenesis. We identify two problems in the use of biomarkers in mechanistic studies. The first problem arises in the case of multifactorial diseases, where different combinations of multiple causes result in patient heterogeneity. The second problem arises when a pathogenic mediator is difficult to measure. This is the case of the oxidative stress (...) (OS) theory of disease, where the causal components are reactive oxygen species (ROS) that have very short half-lives. In this case, it is usual to measure the traces left by the reaction of ROS with biological molecules, rather than the ROS themselves. Borrowing from the philosophical theories of signs, we look at the different facets of biomarkers and discuss their different value and meaning in multifactorial diseases and system medicine to inform their use in patient stratification in personalized medicine. (shrink)

BackgroundFunctional changes after spinal cord injury are related to changes in cortical plasticity. These changes can be measured with electroencephalography and has potential to be used as a clinical biomarker.MethodIn this longitudinal study participants underwent a total of 30 sessions of robotic-assisted gait training over a course of 6 weeks. The duration of each session was 30 min. Resting state EEG was recorded before and after 30-session rehabilitation therapy. To measure gait, we used the Walking Index for Spinal Cord Injury (...) Scale, 10-Meter- Walking Test, Timed-Up-and-Go, and 6-Min-Walking Test. Balance was measured using Berg Balance Scale.ResultsFifteen participants with incomplete SCI who had AIS C or D injuries based on American Spinal Cord Injury Association Impairment Scale classification were included in this study. Mean age was 35.7 years and the mean time since injury was 17.08 months. All participants showed clinical improvement with the rehabilitation program. EEG data revealed that high beta EEG activity in the central area had a negative correlation with gait and balance measured at baseline, in a way that greater high beta EEG power was related to worse clinical function at baseline. Moreover, improvement in gait and balance had negative correlations with the change in alpha/theta ratio in the parietal area.ConclusionIn SCI, functional impairment and subsequent improvement following rehabilitation therapy with RAGT correlated with the change in cortical activity measured by EEG. Our results suggest that EEG alpha/theta ratio may be a potential surrogate marker of functional improvement during rehabilitation. Future studies are necessary to improve and validate these findings as a neurophysiological biomarker for SCI rehabilitation. (shrink)

The main aim of our study was to determinate whether a repeated bout (RB) (vs. first bout [FB]) of sprint interval cycling exercise (SIE) is sufficient to mitigate SIE-induced psychological and physiological biomarker kinetics within 48 h after the exercise. Ten physically active men (age, 22.6 ± 5.2 years; VO2max, 44.3 ± 5.7 ml/kg/min) performed the FB of sprint interval cycling exercise (12 repeats of 5 s each) on one day and the RB 2 weeks later. The following parameters were (...) measured: motor performance (voluntary, electrically induced and isokinetic skeletal muscle contraction torque, and central activation ratio [CAR]); stress markers (BDNF, cortisol, norepinephrine, and epinephrine); inflammatory markers (IL-6, IL-10, and TNF-); metabolic markers (glucose and lactate); muscle and rectal temperature; cycling power output; and psychological perceptions. The average cycling power output and neuromuscular fatigue after exercise did not differ between the FB and RB. There were significant decreases in cortisol and BDNF concentration at 12 h (P < 0.05) and 24 h (P < 0.001) after the FB, respectively. The decrease in cortisol concentration observed 12 h after exercise was significantly greater after the RB (P < 0.05) than after the FB. The immune-metabolic response to the RB (vs. FB) SIE was suppressed and accompanied by lower psychological exertion. Most of the changes in psychological and physiological biomarkers in the FB and RB were closely related to the response kinetics of changes in BDNF concentration. (shrink)

What makes a high-quality biomarker experiment? The success of personalized medicine hinges on the answer to this question. In this paper, I argue that judgment about the quality of biomarker experiments is mediated by the problem of theoretical underdetermination. That is, the network of biological and pathophysiological theories motivating a biomarker experiment is sufficiently complicated that it often frustrates valid interpretation of the experimental results. Drawing on a case-study in biomarker diagnostic development from neurooncology, I argue that this problem of (...) underdetermination can be overcome with greater coordination across the biomarker research trajectory. I then sketch an account for how coordination across a research trajectory can be evaluated. I ultimate conclude that what makes a high-quality biomarker experiment must be judged by the epistemic contribution it makes to this coordinated research effort. (shrink)

As functional magnetic resonance imaging becomes more precise and the data more extensive, neuroscientists like Kent Kiehl are raising the possibility that such research might someday, together with existing clinical assessment tools, increase our ability to predict the likelihood that a given convict will commit another crime after getting out of prison. Such an advance would provoke challenging questions about our notions of liberty and personal autonomy, with potentially chilling ramifications.

Many healthy volunteers choose to take part in Alzheimer’s disease prevention studies because they want to know whether they will develop dementia—and what they can do to reduce their risk—and are therefore interested in learning the results of AD biomarker tests. Proponents of AD biomarker disclosure often refer to the personal utility of AD biomarkers, claiming that research participants will be able to use AD biomarker information for personal purposes, such as planning ahead or making important life decisions. In (...) this paper, the claim that AD biomarkers have personal utility for asymptomatic individuals is critically assessed. It demonstrates that in the absence of clinical validity, AD biomarkers cannot have personal utility and do not serve research participants’ autonomy. Over the next few years, many research groups will be confronted with participants’ preferences to learn the results of AD biomarker tests. When researchers choose to make results available upon explicit request, they should ensure adequate information provision and education, notably on the uncertain clinical significance of AD biomarker information. Routine disclosure of AD biomarkers to cognitively unimpaired individuals in research settings cannot be justified with an appeal to the personal utility of AD biomarker information. (shrink)

We thank Parker and Wright for engaging in this roundtable debate in such a spirited way. The ‘Pharmacogenetic [test] to Avoid Loss of Hearing’ Trial is the first time a genetic point of care test has been applied in the acute neonatal setting; therefore, it is not surprising that questions have been raised which require debate, discussion and clarification. Parker and Wright misattribute several assumptions to the roundtable authors, which we would like to clarify here. Since they raise wider questions (...) about the PALOH trial itself, several of the roundtable discussants have made a joint response. (shrink)

Stroke remains one of the leading causes of various disabilities, including debilitating motor and language impairments. Though various treatments exist, post-stroke impairments frequently become chronic, dramatically reducing daily life quality, and requiring specific rehabilitation. A critical goal of chronic stroke rehabilitation is to induce, usually through behavioral training, experience-dependent plasticity processes in order to promote functional recovery. However, the efficiency of such interventions is typically modest, and very little is known regarding the neural dynamics underpinning recovery processes and possible (...) class='Hi'>biomarkers of their efficiency. Some studies have emphasized specific alterations of excitatory–inhibitory balance within distributed neural networks as an important recovery correlate. Neural processes sensitive to these alterations, such as task-dependent oscillatory activity in beta as well as alpha bands, may be candidate biomarkers of chronic stroke functional recovery. In this review, we discuss the results of studies on motor and language recovery with a focus on oscillatory processes centered around the beta band and their modulations during functional recovery in chronic stroke. The discussion is based on a framework where task-dependent modulations of beta and alpha oscillatory activity, generated by the deep cortical excitatory–inhibitory microcircuits, serve as a neural mechanism of domain-general top-down control processes. We discuss the findings, their limitations, and possible directions for future research. (shrink)

While the HVTN 505 trial showed no overall efficacy of the tested vaccine to prevent HIV infection over placebo, markers measuring immune response to vaccination were strongly correlated with infection. This finding generated the hypothesis that some marker-defined vaccinated subgroups were partially protected whereas others had their risk increased. This hypothesis can be assessed using the principal stratification framework (Frangakis and Rubin, 2002) for studying treatment effect modification by an intermediate response variable, using methods in the sub-field of principal surrogate (...) (PS) analysis that studies multiple principal strata. Unfortunately, available methods for PS analysis require an augmented study design not available in HVTN 505, and make untestable structural risk assumptions, motivating a need for more robust PS methods. Fortunately, another sub-field of principal stratification, survivor average causal effect (SACE) analysis (Rubin, 2006) – which studies effects in a single principal stratum – provides many methods not requiring an augmented design and making fewer assumptions. We show how, for a binary intermediate response variable, methods developed for SACE analysis can be adapted to PS analysis, providing new and more robust PS methods. Application to HVTN 505 supports that the vaccine partially protected individuals with vaccine-induced T-cells expressing certain combinations of functions. (shrink)

In clinical research – whether pharmaceutical, genetic or biomarker research – it is important to protect research participants’ autonomy and to ensure or strengthen their control over health-related decisions. Empirical–ethical studies have argued that both the ethical concept and the current legalistic practice of informed consent should be adapted to the complexity of the clinical environment. For this, a better understanding of recruitment, for which also the physician–patient relationship plays an important role, is needed. Our aim is to ethically reflect (...) communication processes by identifying patterns used by physicians to motivate patients’ participation in clinical research and to assess whether patients also use these patterns in formulating their own research motivation. We conducted a secondary analysis with empirical data from a research project involving physicians and patients in a clinical research setting of a biomarker study for rectal cancer treatment. Our empirical data included observations of physician–patient consultations and semi-structured interviews with patients. Overall, we collected 93 interviews. We found two dominant communication patterns, which physicians applied for motivating patients to take part in this research study. Some forms of these patterns tend to mislead patients’ understanding, while others could justifiably be applied in this consultation setting without undermining patients’ autonomy. This insight that the physician–patient communication has a strong influence on patients increases the importance to strengthen physicians’ ethically acceptable communication patterns regarding research participation. We further suggest that there is a need for a critical reflection of the ethics committee’s requirements for information regarding research participation. (shrink)

Previously diagnosed by symptoms alone, Alzheimer's disease is now also defined by measures of amyloid and tau, referred to as “biomarkers.” Biomarkers are detectible up to twenty years before symptoms present and open the door to predicting the risk of Alzheimer's disease. While these biomarkers provide information that can help individuals and families plan for long-term care services and supports, insurers could also use this information to discriminate against those who are more likely to need such services. (...) In this article, we evaluate whether state laws prohibit long-term care insurers from making discriminatory or unfair underwriting and coverage decisions based Alzheimer's disease biomarkers status. We report data demonstrating that current state laws do not provide meaningful protections from discrimination by long-term care insurers based on biomarker information. (shrink)

The use of biomarkers holds great promise for the development of new therapeutics and the acceleration of clinical research. However, biomarkers must be validated — a complex and costly endeavor. Importantly, biomarker validation is meaningfully shaped by economic and policy-driven incentives.

Small non‐coding RNAs (microRNAs or miRs) represent one of the most fertile areas of cancer research and recent advances in the field have prompted us to reconsider the traditional concept of cancer. Some miRs exert negative control over the expression of numerous oncoproteins in normal cells and consequently their deregulation is believed to be an important mechanism underlying cancer development and progression. Owing to their distinct patterns of expression associated with cancer type, remarkable stability and presence in blood and other (...) body fluids, miRs are considered to be highly promising cancer biomarkers. The identification of “miR signatures” associating cancer cell phenotypes with disease outcome and specific risk factor exposures will undoubtedly open new avenues for early diagnosis and therapy of cancer, as well as for the development of novel strategies for cancer prevention. (shrink)

Although data sharing platforms host diverse data types the features of these platforms are well-suited to facilitating biomarker research. Given the current state of biomarker discovery, an innovative paradigm to accelerate biomarker discovery is to utilize platforms such as Vivli to leverage researchers' abilities to integrate certain classes of biomarkers.

When there have been substantial failures by institutional leadership in their oversight responsibility to protect research integrity, the public should demand that these be recognized and addressed by the institution itself, or the funding bodies. This commentary discusses a case of research failures in developing genomic predictors for cancer risk assessment and treatment at a leading university. In its review of this case, the Office of Research Integrity, an agency within the US Department of Health and Human Services, focused their (...) report entirely on one individual faculty member and made no comment on the institution’s responsibility and its failure to provide adequate oversight and investigation. These actions missed an important opportunity to emphasize the institution’s critical responsibilities in oversight of research integrity and the importance of institutional transparency and accountability. (shrink)

We have developed a first generation tool for the unbiased identification and characterization of human pluripotent stem cells, termed PluriTest. This assay utilizes all the information contained on a microarray and abandons the conventional stem cell marker concept. Stem cells are defined by the ability to replenish themselves and to differentiate into more mature cell types. As differentiation potential is a property that cannot be directly proven in the stem cell state, biologists have to rely on correlative measurements in stem (...) cells associated with differentiation potential. Unfortunately, most, if not all, of those markers are only valid within narrow limits of specific experimental systems. Microarray technologies and recently next‐generation sequencing have revolutionized how cellular phenotypes can be characterized on a systems‐wide level. Here we discuss the challenges PluriTest and similar global assays need to address to fulfill their enormous potential for industrial, diagnostic and therapeutic applications. (shrink)

The environment can elicit biological responses such as oxidative stress (OS) and inflammation as a consequence of chemical, physical, or psychological changes. As population studies are essential for establishing these environment-organism interactions, biomarkers of OS or inflammation are critical in formulating mechanistic hypotheses. By using examples of stress induced by various mechanisms, we focus on the biomarkers that have been used to assess OS and inflammation in these conditions. We discuss the difference between biomarkers that are the (...) result of a chemical reaction (such as lipid peroxides or oxidized proteins that are a result of the reaction of molecules with reactive oxygen species) and those that represent the biological response to stress, such as the transcription factor NRF2 or inflammation and inflammatory cytokines. The high-throughput and holistic approaches to biomarker discovery used extensively in large-scale molecular epidemiological exposome are also discussed in the context of human exposure to environmental stressors. We propose to consider the role of biomarkers as signs and to distinguish between signs that are just indicators of biological processes and proxies that one can interact with and modify the disease process. (shrink)

IntroductionThis study aimed to evaluate, in adults with mild cognitive impairment, the brain atrophy that may distinguish between three AT biomarker-based profiles, and to determine its clinical value.MethodsStructural MRI was employed to evaluate the volume and cortical thickness differences in MCI patients with different AT profiles, namely, A−T−−: normal AD biomarkers; A+T−−: AD pathologic change; and A+T++: prodromal AD. Sensitivity and specificity of these changes were also estimated.ResultsAn initial atrophy in medial temporal lobe areas was found in the A+T−− (...) and A+T++ groups, spreading toward the parietal and frontal regions in A+T++ patients. These structural changes allowed distinguishing AT profiles within the AD continuum; however, the profiles and their pattern of neurodegeneration were unsuccessful to determine the current clinical status.ConclusionsMRI is useful in the determination of the specific brain structural changes of AT profiles along the AD continuum, allowing differentiation between MCI adults with or without pathological AD biomarkers. (shrink)

Background To describe the preferences for disclosure of individual biomarker results among mothers participating in a longitudinal birth cohort. Methods We surveyed 343 mothers that participated in the Health Outcomes and Measures of the Environment Study about their biomarker disclosure preferences. Participants were told that the study was measuring pesticide metabolites in their biological specimens, and that the health effects of these low levels of exposure are unknown. Participants were asked whether they wanted to receive their results and their child's (...) results. In addition, they were asked about their preferred method (letter vs in person) and format (more complex vs less complex) for disclosure of results. Results Almost all of the study participants wanted to receive their individual results (340/343) as well as their child's results (342/343). However, preferences for receiving results differed by education level. Mothers with less than a college degree preferred in-person disclosure of results more often than mothers with some college education or a college degree (34.3% vs 17.4% vs 7.9%, p<0.001). Similarly, mothers with less than a college education preferred a less complex disclosure format than mothers with some college education or a college degree (59.7% vs 79.1% vs 86.3%, p<0.0001). Conclusion While almost all study participants preferred to receive results of their individual biomarker tests, level of education was a key factor in predicting preferences for disclosure of biomarker results. To ensure effective communication of this information, disclosure of biomarker results should be tailored to the education level of the study participants. (shrink)

Precise and timely diagnosis of Parkinson’s disease is important to control its progression among subjects. Currently, a neuroimaging technique called dopaminergic imaging that uses single photon emission computed tomography (SPECT) with 123I-Ioflupane is popular among clinicians for detecting Parkinson’s disease in early stages. Unlike other studies, which consider only low-level features like gray matter, white matter, or cerebrospinal fluid, this study explores the non-linear relation between different biomarkers (SPECT + biological) using deep learning and multivariate logistic regression. Striatal binding (...) ratios are obtained using 123I-Ioflupane SPECT scans from four brain regions which are further integrated with five biological biomarkers to increase the diagnostic accuracy. Experimental results indicate that this investigated approach can differentiate subjects with 100% accuracy. The obtained results outperform the ones reported in the literature. Furthermore, logistic regression model has been developed for estimating the Parkinson’s disease onset probability. Such models may aid clinicians in diagnosing this disease. (shrink)

Motivation: There is an ongoing search for definitive and reliable biomarkers to forecast or predict imminent seizure onset, but to date most research has been limited to EEG with sampling rates <1,000 Hz. High-frequency oscillations have gained acceptance as an indicator of epileptic tissue, but few have investigated the temporal properties of HFOs or their potential role as a predictor in seizure prediction. Here we evaluate time-varying trends in preictal HFO rates as a potential biomarker of seizure prediction.Methods: HFOs (...) were identified for all interictal and preictal periods with a validated automated detector in 27 patients who underwent intracranial EEG monitoring. We used LASSO logistic regression with several features of the HFO rate to distinguish preictal from interictal periods in each individual. We then tested these models with held-out data and evaluated their performance with the area-under-the-curve of their receiver-operating curve. Finally, we assessed the significance of these results using non-parametric statistical tests.Results: There was variability in the ability of HFOs to discern preictal from interictal states across our cohort. We identified a subset of 10 patients in whom the presence of the preictal state could be successfully predicted better than chance. For some of these individuals, average AUC in the held-out data reached higher than 0.80, which suggests that HFO rates can significantly differentiate preictal and interictal periods for certain patients.Significance: These findings show that temporal trends in HFO rate can predict the preictal state better than random chance in some individuals. Such promising results indicate that future prediction efforts would benefit from the inclusion of high-frequency information in their predictive models and technological architecture. (shrink)