Biomarkers Of Disease Progression Research Articles

Clinical Validation of the Somatic FANCD2 Mutation (c.2022-5C>T) as a Novel Molecular Biomarker for Early Disease Progression in Chronic Myeloid Leukemia: A Case–Control Study

Background: Chronic myeloid leukemia (CML) results from chromosomal translocation t(9;22) leading to the formation of the BCR-ABL fusion oncogene. CML has three stages: the chronic phase (CP), the accelerated phase (AP), and the blast crisis (BC). Tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of CML. TKIs work well in CP-CML, and these patients have a survival rate similar to the normal population, but TKIs are less effective in advanced-phase CML. Even with current advances in treatment, BC-CML patients have an average overall survival of less than a year. Early recognition of CML patients at risk of disease progression can help in timely interventions with appropriate TKIs or other therapeutic modalities. Although some markers of disease progression like BCR-ABL kinase domain, ASXL1, and GATA2 mutations are available, no universal and exclusively specific molecular biomarkers exist to early diagnose CML patients at risk of CML progression for timely therapeutic interventions to delay or minimize blast crisis transformation in CML. A recent study found that all BC-CML patients harbored the FANCD2 (c.2022-5C>T) mutation. Therefore, the current study was designed to detect this FANCD2 mutant in AP-CML (early progression phase) and to clinically validate its potential as a novel molecular biomarker of early CML progression from CP to AP. Methods: Our study comprised 123 CP-CML (control group) and 60 AP-CML patients (experimental group) from 2 oncology centers, from January 2020 to July 2023. Mean hemoglobin level, WBC count, platelet count, treatment type, hepatomegaly, splenomegaly, and survival status of AP-CML patients were significantly different from those of CP-CML patients. However, as these clinical parameters cannot help in the early detection of patients at risk of CML progression, there was a need for a clinically validated biomarker of AP-CML. DNA was extracted from the patients’ blood samples, and the FANCD2 gene was sequenced using an Illumina NextSeq500 next-generation sequencer (NGS). Results: The NGS analysis revealed a unique splice-site mutation in the FANCD2 gene (c.2022-5C>T). This mutation was detected in the majority (98.3%) of AP-CML patients but in none of the CP-CML patients or healthy control sequences from genomic databases. The mutation was confirmed by Sanger sequencing. FANCD2 is a member of the Fanconi anemia pathway genes involved in DNA repair and genomic stability, and aberrations of this gene are associated with many cancers. Conclusions: In conclusion, our study shows that the somatic FANCD2 (c.2022-5C>T) mutation is a new molecular biomarker for early CML progression. We recommend further clinical validation of this biomarker in prospective clinical trials.

Clinical Validation of the Somatic FANCD2 Mutation (c.2022-5C>T) as a Novel Molecular Biomarker for Early Disease Progression in Chronic Myeloid Leukemia: A Case–Control Study

Background: Chronic myeloid leukemia (CML) results from chromosomal translocation t(9;22) leading to the formation of the BCR-ABL fusion oncogene. CML has three stages: the chronic phase (CP), the accelerated phase (AP), and the blast crisis (BC). Tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of CML. TKIs work well in CP-CML, and these patients have a survival rate similar to the normal population, but TKIs are less effective in advanced-phase CML. Even with current advances in treatment, BC-CML patients have an average overall survival of less than a year. Early recognition of CML patients at risk of disease progression can help in timely interventions with appropriate TKIs or other therapeutic modalities. Although some markers of disease progression like BCR-ABL kinase domain, ASXL1, and GATA2 mutations are available, no universal and exclusively specific molecular biomarkers exist to early diagnose CML patients at risk of CML progression for timely therapeutic interventions to delay or minimize blast crisis transformation in CML. A recent study found that all BC-CML patients harbored the FANCD2 (c.2022-5C>T) mutation. Therefore, the current study was designed to detect this FANCD2 mutant in AP-CML (early progression phase) and to clinically validate its potential as a novel molecular biomarker of early CML progression from CP to AP. Methods: Our study comprised 123 CP-CML (control group) and 60 AP-CML patients (experimental group) from 2 oncology centers, from January 2020 to July 2023. Mean hemoglobin level, WBC count, platelet count, treatment type, hepatomegaly, splenomegaly, and survival status of AP-CML patients were significantly different from those of CP-CML patients. However, as these clinical parameters cannot help in the early detection of patients at risk of CML progression, there was a need for a clinically validated biomarker of AP-CML. DNA was extracted from the patients’ blood samples, and the FANCD2 gene was sequenced using an Illumina NextSeq500 next-generation sequencer (NGS). Results: The NGS analysis revealed a unique splice-site mutation in the FANCD2 gene (c.2022-5C>T). This mutation was detected in the majority (98.3%) of AP-CML patients but in none of the CP-CML patients or healthy control sequences from genomic databases. The mutation was confirmed by Sanger sequencing. FANCD2 is a member of the Fanconi anemia pathway genes involved in DNA repair and genomic stability, and aberrations of this gene are associated with many cancers. Conclusions: In conclusion, our study shows that the somatic FANCD2 (c.2022-5C>T) mutation is a new molecular biomarker for early CML progression. We recommend further clinical validation of this biomarker in prospective clinical trials.

Muscle MRI as a biomarker of disease activity and progression in myotonic dystrophy type 1: a longitudinal study.

Myotonic dystrophy type 1 (DM1) is an autosomal dominant disease characterized by myotonia and progressive muscular weakness and atrophy. The aim of this study was to investigate the usefulness of longitudinal muscle MRI in detecting disease activity and progression in DM1, and to better characterize muscle edema, fat replacement and atrophy overtime. This is a prospective, observational, longitudinal study including 25 DM1 patients that performed at least two muscle MRIs. Demographic and genetic characteristics were recorded. Muscular Impairment Rating Scale (MIRS) and MRC score were performed within 3months from MRIs at baseline (BL) and at follow-up (FU). We analysed 32 muscles of lower body (LB) and 17 muscles of upper body (UB) by T1 and STIR sequences. T1-, STIR- and atrophy scores and their variations were evaluated. Correlations between MRIs' scores and demographic, clinical and genetic characteristics were analysed. Eighty (80%) of patients showed fat replacement progression at FU. The median T1 score progression (ΔT1-score) was 1.3% per year in LB and 0.5% per year in UB. The rate of fat replacement progression was not homogenous, stratifying patients from non-progressors to fast progressors (> 3% ΔT1-score per year). Half of the STIR-positive muscles at BL showed T1-score progression at FU. Two patients with normal MRI at baseline only showed STIR-positive muscle at FU, marking the disease activity onset. STIR positivity at baseline correlated with fat replacement progression (ΔT1-score; p < 0.0001) and clinical worsening at FU (ΔMRC-score; p < 0.0001). Sixty-five (65%) of patients showed STIR- and fat replacement-independent muscle atrophy progression, more evident in UB. Muscle MRI represents a sensitive biomarker of disease activity, severity, and progression in DM1. STIR alterations precede fat replacement and identify patients with a higher risk of disease progression, while T1-sequences reveal atrophy and fat replacement progression before clinical worsening.

Changes in saccadic intrusions over time as an objective biomarker to follow ALS disease progression

Objective: Saccadic Intrusions (SIs) are abnormal eye movements during gaze fixation. Studies have indicated the clinical relevance of SIs, especially of square wave jerks (SWJ) in ALS. We used a software-based platform to extract SIs as a part of an interventional drug trial. The objective was to examine SIs’ change over time as a potential biomarker of ALS disease progression. Methods: 28 ALS patients (61.95 ± 8.6 years) were assessed with the revised ALS Functional Rating Scale (ALSFRS-R) and with an oculometric test. Changes of SIs over time and correlations with ALSFRS-R and its bulbar subscale were calculated. A power calculation was conducted to understand the practical implications of results. Results: A significant increase of SWJ over trial duration was observed, with an increase in frequency (mean rise of 0.14 ± 0.28, p < 0.01), amplitude (0.001 ± 0.0016 degrees, p < 0.005), overall duration of SWJ (0.13 ± 0.25, in %, p < 0.01), and in their relative part out of all intrusions (0.18 ± 0.32, in %, p < 0.005). Negative correlations were found with the bulbar subscale (R=-0.43, −0.41, −0.39 and −0.47, respectively, p < 0.001). The required sample size for observing a 40% reduction in bulbar aspects when using the oculometric test (α = 0.05 and β = 0.8), was found to be 150 patients per arm, compared with 200 patients using the bulbar subscale. Conclusions: Evaluation of saccadic intrusions during fixation was able to detect disease progression over time, correlated with ALSFRS-R bulbar subscale. Eye movements can potentially serve as an objective biomarker in ALS clinical trials and reduce the required sample size to show clinical effect of therapies.

Extracellular Vesicles: The Next Generation of Biomarkers and Treatment for Central Nervous System Diseases.

It has been widely established that the characterization of extracellular vesicles (EVs), particularly small EVs (sEVs), shed by different cell types into biofluids, helps to identify biomarkers and therapeutic targets in neurological and neurodegenerative diseases. Recent studies are also exploring the efficacy of mesenchymal stem cell-derived extracellular vesicles naturally enriched with therapeutic microRNAs and proteins for treating various diseases. In addition, EVs released by various neural cells play a crucial function in the modulation of signal transmission in the brain in physiological conditions. However, in pathological conditions, such EVs can facilitate the spread of pathological proteins from one brain region to the other. On the other hand, the analysis of EVs in biofluids can identify sensitive biomarkers for diagnosis, prognosis, and disease progression. This review discusses the potential therapeutic use of stem cell-derived EVs in several central nervous system diseases. It lists their differences and similarities and confers various studies exploring EVs as biomarkers. Further advances in EV research in the coming years will likely lead to the routine use of EVs in therapeutic settings.

Gray matter alterations in Huntington's disease: A meta-analysis of VBM neuroimaging studies.

Increasing neuroimaging studies have attempted to identify biomarkers of Huntington's disease (HD) progression. Here, we conducted voxel-based meta-analyses of voxel-based morphometry (VBM) studies on HD to investigate the evolution of gray matter volume (GMV) alterations and explore the effects of genetic and clinical features on GMV changes. A systematic review was performed to identify the relevant studies. Meta-analyses of whole-brain VBM studies were performed to assess the regional GMV changes in all HD mutation carriers, in presymptomatic HD (pre-HD), and in symptomatic HD (sym-HD). A quantitative comparison was performed between pre-HD and sym-HD. Meta-regression analyses were used to explore the effects of genetic and clinical features on GMV changes. Twenty-eight studies were included, comparing a total of 1811 HD mutation carriers [including 1150 pre-HD and 560 sym-HD] and 969 healthy controls (HCs). Pre-HD showed decreased GMV in the bilateral caudate nuclei, putamen, insula, anterior cingulate/paracingulate gyri, middle temporal gyri, and left dorsolateral superior frontal gyrus compared with HCs. Compared with pre-HD, GMV decrease in sym-HD extended to the bilateral median cingulate/paracingulate gyri, Rolandic operculum and middle occipital gyri, left amygdala, and superior temporal gyrus. Meta-regression analyses found that age, mean lengths of CAG repeats, and disease burden were negatively associated with GMV atrophy of the bilateral caudate and right insula in all HD mutation carriers. This meta-analysis revealed the pattern of GMV changes from pre-HD to sym-HD, prompting the understanding of HD progression. The pattern of GMV changes may be biomarkers for disease progression in HD.

Synaptic Protein Loss in Extracellular Vesicles Reflects Brain and Retinal Atrophy in People With Multiple Sclerosis.

To assess whether the rate of change in synaptic proteins isolated from neuronally enriched extracellular vesicles (NEVs) is associated with brain and retinal atrophy in people with multiple sclerosis (MS). People with MS were followed with serial blood draws, MRI (MRI), and optical coherence tomography (OCT) scans. NEVs were immunocaptured from plasma, and synaptopodin and synaptophysin proteins were measured using ELISA. Subject-specific rates of change in synaptic proteins, as well as brain and retinal atrophy, were determined and correlated. A total of 50 people with MS were included, 46 of whom had MRI and 45 had OCT serially. The rate of change in NEV synaptopodin was associated with whole brain (rho = 0.31; p = 0.04), cortical gray matter (rho = 0.34; p = 0.03), peripapillary retinal nerve fiber layer (rho = 0.37; p = 0.01), and ganglion cell/inner plexiform layer (rho = 0.41; p = 0.006) atrophy. The rate of change in NEV synaptophysin was also correlated with whole brain (rho = 0.31; p = 0.04) and cortical gray matter (rho = 0.31; p = 0.049) atrophy. NEV-derived synaptic proteins likely reflect neurodegeneration and may provide additional circulating biomarkers for disease progression in MS.

Differential Vulnerability of Hippocampal Subfields to Amyloid and Tau Deposition in the Lewy Body Diseases.

Alzheimer disease (AD) copathologies of β-amyloid and tau are common in the Lewy body diseases (LBD), dementia with Lewy bodies (DLB) and Parkinson disease (PD), and target distinct hippocampal subfields compared with Lewy pathology, including subiculum and CA1. We investigated the hypothesis that AD copathologies impact the pattern of hippocampal subregion volume loss and cognitive function in LBD. This was a cross-sectional and longitudinal, single-center, observational cohort study. Participants underwent neuropsychological testing and 3T-MRI with hippocampal segmentation using FreeSurferV7. PiB-PET and flortaucipir-PET imaging of comorbid β-amyloid (A) and tau (T) were acquired. The association of functional cognition, β-amyloid, and tau loads with hippocampal subregion volume was assessed. The contribution of subregion volumes to the relationship of AD-related deposits on functional cognition was examined with mediation analysis. The effects of AD-related deposits on the rate of subregion atrophy were evaluated with mixed-effects models. Of 103 participants (mean age: 70.3 years; 37.3% female), 52 had LBD with impaired cognition (LBD-I), 26 had normal cognition (LBD-N), and 25 were A- healthy controls (HCs). Volumes of hippocampal subregions prone to AD copathologies, including subiculum (F = 6.9, p = 0.002), presubiculum (F = 7.3, p = 0.001), and parasubiculum (F = 5.9, p = 0.004), were reduced in LBD-I compared with LBD-N and HC. Volume was preserved in CA2/3, Lewy pathology susceptible subregions. In LBD-I, reduced CA1, subiculum, and presubiculum volumes were associated with greater functional cognitive impairment (all p < 0.05). Compared with HC, subiculum volume was reduced in A+T+ but not A-T- participants (F = 2.62, p = 0.043). Reduced subiculum volume mediated the effect of amyloid on functional cognition (0.12, 95% CI: 0.005 to 0.26, p = 0.040). In 26 longitudinally-evaluated participants, baseline tau deposition was associated with faster CA1 (p = 0.021) and subiculum (p = 0.002) atrophy. In LBD, volume loss in hippocampal output subregions-particularly the subiculum-is associated with functional cognition and AD-related deposits. Tau deposition appears to accelerate subiculum and CA1 atrophy, whereas Aβ does not. Subiculum volume may have value as a biomarker of AD copathology-mediated neurodegeneration and disease progression.

Top-Down Proteomics Identifies Plasma Proteoform Signatures of Liver Cirrhosis Progression.

Cirrhosis, advanced liver disease, affects 2-5 million Americans. While most patients have compensated cirrhosis and may be fairly asymptomatic, many decompensate and experience life-threatening complications such as gastrointestinal bleeding, confusion (hepatic encephalopathy), and ascites, reducing life expectancy from 12 to less than 2 years. Among patients with compensated cirrhosis, identifying patients at high risk of decompensation is critical to optimize care and reduce morbidity and mortality. Therefore, it is important to preferentially direct them towards specialty care which cannot be provided to all patients with cirrhosis. We used discovery Top-down Proteomics (TDP) to identify differentially expressed proteoforms (DEPs) in the plasma of patients with progressive stages of liver cirrhosis with the ultimate goal to identify candidate biomarkers of disease progression. In this pilot study, we identified 209 DEPs across three stages of cirrhosis (compensated, compensated with portal hypertension, and decompensated), of which 115 derived from proteins enriched in the liver at a transcriptional level and discriminated the three stages of cirrhosis. Enrichment analyses demonstrated DEPs are involved in several metabolic and immunological processes known to be impacted by cirrhosis progression. We have preliminarily defined the plasma proteoform signatures of cirrhosis patients, setting the stage for ongoing discovery and validation of biomarkers for early diagnosis, risk stratification, and disease monitoring.

CSF sphingolipids are correlated with neuroinflammatory cytokines and differentiate neuromyelitis optica spectrum disorder from multiple sclerosis

BackgroundThere is a need for biomarkers of disease progression and therapeutic response in multiple sclerosis (MS). This study aimed to identify cerebrospinal fluid (CSF) lipids that differentiate MS from other...

Role of miRNAs in the Chikungunya virus replication and pathogenesis

Chikungunya virus (CHIKV) is a vector-born alphavirus responsible for chikungunya fever with clinical manifestation of polyarthritis transmitted by Aedes aegypti and Aedes albopictus. Establishing viral pathogenesis needs host machinery modulation, and the microRNAs (miRNA) modulate host cellular machinery to establish the infection or inhibit viral replication. miRNAs are the small noncoding RNA that control the gene expression. They are essential in cell differentiation, growth, development, and apoptosis. It also affects disease progression, cancer, and viral infection. CHIKV infection causes differential expression of miRNA, and miRNA has target genes involved in different cellular functions. These target genes may be crucial in CHIKV replication and cell growth. Suppression or overexpression of these miRNAs may have been linked with CHIKV pathogenesis by regulating immune and signaling pathways. Identification of biomarkers in disease progression through the study of circulating miRNAs during CHIKV infection is an emerging field. Therefore, understanding miRNAs’ differential expression and function during CHIKV infection is essential. The detailed studies on the miRNA-mediated regulatory network will provide new ways to develop miRNA-based therapies.

#2308 The effect of Dapagliflozin on albuminuria and biomarkers associated with renal function in patients with β-thalassemia and/or sickle-cell disease

Abstract Background and Aims Patients with β-thalassemia present already from the 1st year of life with serious anemia thus needing regular blood transfusions in order to attain normal hemoglobin levels. Chronic anemia, iron overload and the use of iron chelating agents have been associated with renal dysfunction. In sickle-cell syndromes, which include sickle-cell anemia and sickle-cell trait, patients present with typical kidney functional and structural defects, resulting in urinary concentrating defects, distal nephron dysfunction and albuminuria. Sodium–glucose cotransporter-2 inhibitors (SGLT-2i) have shown beneficial effects on renal outcomes in large clinical trials with the added benefit of a substantial decrease in albuminuria. The aim of this prospective, non randomized open label study is to investigate the effect of Dapagliflozin at a dose of 10 mg daily on albuminuria and the overall progression of CKD in patients with β-thalassemia and/or sickle-cell disease undergoing regular blood transfusions. Method In this study we included adult patients undergoing regular blood transfusions with a baseline albuminuria of ACR&amp;gt;30 mg/gCr (assessed with a spot urine sample) who received treatment with Dapagliflozin, a second group with no albuminuria that did not receive treatment and a group of adults with no kidney disease (Controls). In all patients renal function biomarkers were measured in urine and serum with commercial ELISA kits (NGAL and uPAR in serum, MMP9 and KIM-1 in urine), while in patients that received Dapagliflozin additional measurements of ACR and eGFR (CKD-EPI formula) were performed after 3 months of treatment initiation. Results In this study we included 16 patients (7 males) with β-thalassemia and/or sickle-cell disease with ACR&amp;gt;30 mg/gCr, 35 patients (17 males) with β-thalassemia and/or sickle-cell disease without albuminuria and 20 controls (13 males). Patients that received Dapagliflozin showed a significant reduction in albuminuria three months post-initiation of treatment (ACR: 0.52 ± 1.2 vs. 0.3 ± 0.68 mg/g, p=0.006) while kidney function showed a slight non-significant reduction (eGFR: 99.3 ± 21.7 vs. 94.7 ± 28.9 ml/min/1.73m2, p=0.36). Concerning the urine and serum biomarkers of tubular dysfunction, inflammation and kidney disease progression, all were significantly increased in patients with β-thalassemia and/or sickle-cell disease in comparison to controls (Table 1). In patients that received treatment with Dapagliflozin, NGAL, MMP-9 and suPAR at 3 months post-treatment initiation did not show any significant reduction (Table 2). Conclusion Patients with β-thalassemia and/or sickle-cell disease show increased urine and serum levels of kidney damage biomarkers in comparison to healthy controls. Treatment of these patients with Dapagliflozin for 3 months has a significant effect in albuminuria reduction while it does not alter urine and serum levels of these biomarkers.

Association of serum Spp1 levels with disease progression in ALS and SBMA.

In comparison with amyotrophic lateral sclerosis (ALS), the contribution of neuroinflammation in spinobulbar muscular atrophy (SBMA) has been less explored. We investigated the role of neuroinflammation in the pathogenesis of ALS and SBMA by analyzing systemic inflammatory markers and osteopontin (Spp1). This study involved 105 ALS, 77 SBMA, and 55 healthy controls. We measured their systemic inflammatory markers, serum Spp1, and cytokine levels (interferon-γ, interleukin [IL]-1β, IL-6, IL-8, IL-10, tumor necrosis factor-α, and IL-17A), investigated correlations between Spp1 levels and clinical features, and evaluated ALS survival rates according to Spp1 levels. In the ALS group, systemic inflammatory markers were significantly higher than in the control and SBMA groups. Spp1 levels were observed to be higher in ALS patients, but the difference was not statistically significant among the study groups. Cytokine profiles were comparable. In ALS, higher Spp1 levels were correlated with lower ALS Functional Rating Scale-Revised (ALSFRS-R) scores (r = -0.25, p = 0.02) and faster disease progression rate (r = 0.37, p < 0.001). After adjusting for other prognostic indicators, high Spp1 levels were independently associated with shorter survival in ALS patients (hazard ratio 13.65, 95% confidence interval 2.57-72.53, p < 0.01). Neuroinflammation does not appear to be a primary contributor to the pathogenesis of SBMA. Serum Spp1 levels may serve as a reliable biomarker for disease progression and prognosis in ALS. These findings expand our understanding of these two distinct motor neuron disorders and offer a potential biomarker for future studies.

A systematic review on the applicability of cell-free DNA level as an obesity biomarker.

Obesity has become a global health concern in recent decades. Utilizing biomarkers presents a promising approach to comprehensively monitor the progress of obesity and its associated health conditions. This review aims to synthesize the available evidence on the correlation between cfDNA level and obesity and to provide insights into the applicability of using cfDNA level as a tool for monitoring progression of obesity. Searches were performed in PubMed and Embase on April 1, 2022. Data and other relevant information were extracted and compiled into a structured table for further analysis. Among 1170 articles screened, 11 articles were included in this review and assessed qualitatively. The results demonstrated that existing evidence mainly focused on three populations, including healthy individuals, cancer patients and pregnant women. Majority of the studies on healthy individuals identified a significant association between cfDNA level and body weight status but not among cancer patients. Varying results were observed among pregnant women at different gestational trimesters. Our review summarized some preliminary evidence on the association between cfDNA level and obesity. More cohort studies in larger scale with comprehensive assessment have to be conducted to examine the applicability of cfDNA as a biomarker for severity and disease progression of obesity.

Cardiovascular autonomic failure in hereditary transthyretin amyloidosis and TTR carriers is an early and progressive disease marker.

The cardiomyopathic and neuropathic phenotype of hereditary transthyretin amyloidosis are well recognized. Cardiovascular autonomic dysfunction is less systematically and objectively assessed. Autonomic and clinical features, quantitative cardiovascular autonomic function, and potential autonomic prognostic markers of disease progression were recorded in a cohort of individuals with hereditary transthyretin amyloidosis and in asymptomatic carriers of TTR variants at disease onset (T0) and at the time of the first quantitative autonomic assessment (T1). The severity of peripheral neuropathy and its progression was stratified with the polyneuropathy disability score. A total of 124 individuals were included (111 with a confirmed diagnosis of hereditary transthyretin amyloidosis, and 13 asymptomatic carriers of TTR variants). Symptoms of autonomic dysfunction were reported by 27% individuals at T0. Disease duration was 4.5 ± 4.0years [mean ± standard deviation (SD)] at autonomic testing (T1). Symptoms of autonomic dysfunction were reported by 78% individuals at T1. Cardiovascular autonomic failure was detected by functional testing in 75% individuals and in 64% of TTR carriers. Progression rate from polyneuropathy disability stages I/II to III/IV seemed to be shorter for individuals with autonomic symptoms at onset [2.33 ± 0.56 versus 4.00 ± 0.69years (mean ± SD)]. Cardiovascular autonomic dysfunction occurs early and frequently in individuals with hereditary transthyretin amyloidosis within 4.5years from disease onset. Cardiovascular autonomic failure can be subclinical in individuals and asymptomatic carriers, and only detected with autonomic function testing, which should be considered a potential biomarker for early diagnosis and disease progression.

Precision brain morphometry using cluster scanning

Abstract Measurement error limits the statistical power to detect group differences and longitudinal change in structural MRI morphometric measures (e.g., hippocampal volume, prefrontal cortical thickness). Recent advances in scan acceleration enable extremely fast T1-weighted scans (~1 minute) that achieve morphometric errors that are close to the errors in longer traditional scans. As acceleration allows multiple scans to be acquired in rapid succession, it becomes possible to pool estimates to increase measurement precision, a strategy known as “cluster scanning.” Here, we explored brain morphometry using cluster scanning in a test-retest study of 40 individuals (12 younger adults, 18 cognitively unimpaired older adults, and 10 adults diagnosed with mild cognitive impairment or Alzheimer’s Dementia). Morphometric errors from a single compressed sensing (CS) 1.0 mm scan (CS) were, on average, 12% larger than a traditional scan using the Alzheimer’s Disease Neuroimaging Initiative (ADNI) protocol. Pooled estimates from four clustered CS acquisitions led to errors that were 34% smaller than ADNI despite having a shorter total acquisition time. Given a fixed amount of time, a gain in measurement precision can thus be achieved by acquiring multiple rapid scans instead of a single traditional scan. Errors were further reduced when estimates were pooled from eight CS scans (51% smaller than ADNI). Neither pooling across a break nor pooling across multiple scans of different spatial resolutions boosted this benefit. We discuss the potential of cluster scanning to improve morphometric precision, boost statistical power, and produce more sensitive disease progression biomarkers.

Abstract PO4-24-10: Prognostic role of SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in the locally advanced and metastatic breast cancer

Abstract Introduction: Breast cancer (BC) is associated with a continuous increase in incidence, with high mortality rates in several countries. There are four immunophenotypes of BC, luminal A, luminal B, triple negative (TN), and HER2+. Some proteins in tumor cells and the tumor microenvironment are part of tumorigenesis and metastases. The CD44 molecule is considered an important marker of the inflammatory response. CD44 is present in all leukocytes and on the surface of tumor stem cells, involving tumor invasion and metastasis. Some authors have demonstrated that the signal transducer and activator of transcription 3 (STAT3) and sex-determining region Y-related group box 2 (SOX2) are related to the regulation of somatic cell division and tumorigenesis and metastasis in BC. Aim: To evaluate SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in locally advanced and metastatic breast cancer. Methods: A cross-sectional study was conducted at the Hospital de Cancer de Pernambuco (HCP) and the Translational Research Laboratory of the Instituto de Medicina Integral Prof. Fernando Figueira (IMIP) from March 2017 to April 2018. Sixty-five women diagnosed with breast cancer participated in this study, aged between 28 and 64. Of these, 51 women had stage III (locally advanced) breast tumors, and 14 with metastatic disease (stage IV). There were 24 healthy women aged 18 to 65 as a control group. The analysis of CD44, SOX2, and STAT3 expression was performed by flow cytometry. Results: elevated levels of CD44+/CD24neg cells and CD44+/CD24neg/SOX2+ cells were observed in the blood of BC patients with luminal B, HER2+, and TN compared to the control group (p&amp;lt; 0.0001). Low CD44+/CD24neg/STAT3+ levels in the patient's blood compared to the control group. Elevated CD44+/CD24neg and CD44+/CD24neg/STAT3+ cells were observed in locally advanced BC compared to metastatic group (p &amp;lt; 0.05). Patients with TNBC had elevated SOX2+T lymphocyte levels compared to luminal B and HER2+ subtypes groups (p&amp;lt; 0.05). HER2+ patients had low levels of T lymphocytes and SOX2+T cells compared to controls and luminal A groups (p &amp;lt; 0.05). High levels of total T cells (p=0.0007) and low SOX2+T lymphocytes (p=0.02) in locally advanced compared to metastatic disease (stage IV). Elevated levels of SOX2+T lymphocytes in patients with negative lymph nodes (N0) compared to N1 and N2 groups (p=0.004 and p &amp;lt; 0.0001, respectively). High levels of CD44+/CD24negSTAT3+ cells and T lymphocytes and low levels of STAT3+T lymphocytes in locally advanced TN subtype (stage III) compared to metastatic (stage IV). Conclusion: SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in peripheral blood are prognostic roles in breast cancer. SOX2 and STAT3 expression are potential predictive biomarkers of disease progression in breast cancer regardless of tumor subtype. Investigating these biomarkers in peripheral blood has some advantages because peripheral blood collection is less invasive, easy to access, and allows evaluation at diagnosis, during treatment, and in cases of recurrence. Citation Format: Denise Viana, Victor Andrade, Marcelo Salgado, Carolina Vasconcelos, Leuridan Torres. Prognostic role of SOX2 and STAT3 expression on circulating T lymphocytes and CD44+/CD24neg cells in the locally advanced and metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-24-10.

Identification of Early Transcriptional Markers of Autosomal Dominant Polycystic Kidney Disease Cystic Epithelial Cells

Study objective: Mechanisms driving autosomal dominant polycystic kidney disease (ADPKD) cystogenesis, a hallmark of this lethal monogenic disease, are not well understood and reliable biomarkers are scarce. We sought to explore transcriptional changes in ADPKD models with suppressed and non-suppressed cystic phenotype to explore mechanisms driving ADPKD cystogenesis and identify potential biomarkers in disease progression. Hypothesis: Early-stage kidneys from a model in which cystic disease is suppressed by expression of the polycystin-1 C-terminal tail (CTT), a 200 amino acid portion of the larger polycystin-1 protein that is dysregulated in ADPKD, exhibit a differential transcriptional profile from early-stage kidneys in a non-suppressed model. Methodology: Orthologous doxycycline-inducible Pkd1fl/fl;Pax8rtTA;Teto-Cre ADPKD C57BL/6N mouse models expressing CTT ( Pkd1-KO+CTT) or not ( Pkd1-KO) were induced between 4-6 weeks and aged to 10 weeks. We performed single cell RNA sequencing (scRNA-seq) with single cell kidney suspensions from biological replicates that were pooled and processed for cDNA synthesis and library preparation with 10X Chromium technology. Reads were aligned using the 10X Genomics CellRanger pipeline and further processed using the gene cell-inverse cell frequency (gf-icf) pipeline. Data: Clusters corresponding to tubule segments were identified using established annotations. Several novel clusters defined by expression of multiple markers, including Jarid2, Tmtc2, and Filip1l, were identified in the Pkd1-KO model. These clusters were sparsely populated in Pkd1-KO+CTT samples, suggesting that they may correspond to cyst epithelial cells that are suppressed by CTT expression. Each of these novel clusters included cells whose markers identified them from distinct tubule segments (e.g. Sglt2, Umod, S100g), suggesting that cells of different segments are clustered together by virtue of sharing the putative cyst cell transcriptional signature. Importantly, at 10 weeks there are no significant differences in disease endpoints such as kidney weight to body weight, serum creatinine, blood urea nitrogen, or kidney morphology between the Pkd1-KO+CTT and Pkd1-KO models, suggesting that the cells assigned to the cystic epithelial cell clusters exhibit early identifiable differences in transcriptional programming. Summary of results: scRNA-seq at an early timepoint reveals novel transcriptional makers of putative cystic epithelial cells. The protein expression levels of individual markers are being assessed. Conclusions: These results suggest that there are epithelial cells early in disease progression exhibiting a unique transcriptional signature that may elucidate the mechanisms of cyst formation and that may provide new candidate biomarkers. This work was funded in part by the NIH F31 DK135356 (VR), NIH RC2 DK120534-01 (MJC), PR191158 Department of Defense (MJC), and PKD 905682 Foundation for Research in Polycystic Kidney Disease Research Grant (MJC). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Prodromal Status of Rapid Eye Movement Sleep Behavior Disorder: Clinical Significance and Future Perspectives

Rapid eye movement (REM) sleep behavior disorder (RBD) is a prodromal stage for major neurodegenerative diseases, particularly α-synucleinopathies. Recently, the spectrum of RBD is expanding and its prodromal state has been recognized and categorized into isolated REM sleep without atonia and isolated dream-enacting behavior. Although unclear, prodromal RBD frequently occurs in the aged population, with a significantly high phenoconversion rate to RBD and an increased risk of developing neurodegenerative disorders. More active and structured general surveillance of this condition may contribute to the effective modulation of major neurodegenerative diseases. However, the clinical and polysomnographic profiles of prodromal RBD, methods for effective screening and diagnosis of prodromal RBD, and biomarkers for disease progression and phenoconversion must be investigated.

Spatially Resolved Association of Structural Biomarkers on Retinal Function in Non-Exudative Age-Related Macular Degeneration Over 4 Years.

To longitudinally assess the impact of high-risk structural biomarkers for natural disease progression in non-exudative age-related macular degeneration (AMD) on spatially resolved mesopic and scotopic fundus-controlled perimetry testing. Multimodal retinal imaging data and fundus-controlled perimetry stimuli points were semiautomatically registered according to landmark correspondences at each annual visit over a period of up to 4 years. The presence of sub-RPE drusen, subretinal drusenoid deposits, pigment epithelium detachments (PEDs), hyper-reflective foci (HRF), vitelliform lesions, refractile deposits, and incomplete RPE and outer retinal atrophy (iRORA) and complete RPE and outer retinal atrophy (cRORA) were graded at each stimulus position and visit. Localized retinal layer thicknesses were extracted. Mixed-effect models were used for structure-function correlation. Fifty-four eyes of 49 patients with non-exudative AMD (mean age, 70.7 ± 9.1years) and 27 eyes of 27 healthy controls (mean age, 63.4 ± 8.9years) were included. During study course, presence of PED had the highest functional impact with a mean estimated loss of -1.30 dB (P < 0.001) for mesopic and -1.23 dB (P < 0.001) for scotopic testing, followed by HRF with -0.89 dB (mesopic, P = 0.001) and -0.87 dB (scotopic, P = 0.005). Subretinal drusenoid deposits were associated with a stronger visual impairment (mesopic, -0.38 dB; P = 0.128; scotopic, -0.37 dB; P = 0.172) compared with sub-RPE drusen (-0.22 dB, P = 0.0004; -0.18 dB, P = 0.006). With development of c-RORA, scotopic retinal sensitivity further significantly decreased (-2.15 dB; P = 0.02). Thickening of the RPE-drusen-complex and thinning of the outer nuclear layer negatively impacted spatially resolved retinal sensitivity. The presence of PED and HRF had the greatest prognostic impact on progressive point-wise sensitivity losses. Higher predominant rod than cone-mediated localized retinal sensitivity losses with early signs of retinal atrophy development indicate photoreceptor preservation as a potential therapeutic target for future interventional AMD trials.