Transcriptome-wide profiling identifies colon cancer-associated m6A transcripts and potential RNA methyl modifiers.

BACKGROUND: N6-methyladenosine (m6A) is a prevalent and crucial RNA methylation modification that plays a significant role in various biological and pathological processes. The dysregulation of m6A has been linked to the initiation, progression, and metastasis of several cancer types, including colon cancer. The transcriptome of colon cancer indeed provides insight into dysregulated coding and non-coding RNAs, but it does not reveal the mechanisms, such as m6A modifications, that determine post-transcriptional and pre-translational regulations. This study using MeRIP sequencing aims to explain the distribution of m6A modification across altered gene expression and its association with colon cancer. METHODS AND RESULTS: The levels of m6A in different colon cancer cell lines were quantified and correlated with the expression of m6A modifiers such as writers, readers, and erasers. Our results showed that global m6A levels in colon cancer were associated with METTL14, YTHDF2, and YTHDC1. We performed Epi-transcriptome profiling of m6A in colon cancer cell lines using Methylated RNA Immunoprecipitation (MeRIP) sequencing. The differential methylation analysis revealed 7312 m6A regions among the colon cancer cell lines. Our findings indicated that the m6A RNA methylation modifications were mainly distributed in the last exonic and 3' untranslated regions. We also discovered that non-coding RNAs such as miRNA, lncRNA, and circRNA carry m6A marks. Gene set enrichment and motif analysis suggested a strong association of m6A with post-transcriptional events, particularly splicing control. Overall, our study sheds light on the potential role of m6A in colon cancer and highlights the importance of further investigation in this area. CONCLUSION: This study reports m6A enrichment in the last exonic regions and 3' UTRs of mRNA transcripts in colon cancer. METTL14, YTHDF2, and YTHDC1 were the most significant modifiers in colon cancer cells. The functions of m6A-modified genes were found to be RNA methylation and RNA capping. Overall, the study illustrates the transcriptome-wide distribution of m6A and its eminent role in mRNA splicing and translation control of colon cancer.

Functional alteration due to structural damage is network dependent: insight from multiple sclerosis.

Little is known about how the brain's functional organization changes over time with respect to structural damage. Using multiple sclerosis as a model of structural damage, we assessed how much functional connectivity (FC) changed within and between preselected resting-state networks (RSNs) in 122 subjects (72 with multiple sclerosis and 50 healthy controls). We acquired the structural, diffusion, and functional MRI to compute functional connectomes and structural disconnectivity profiles. Change in FC was calculated by comparing each multiple sclerosis participant's pairwise FC to controls, while structural disruption (SD) was computed from abnormalities in diffusion MRI via the Network Modification tool. We used an ordinary least squares regression to predict the change in FC from SD for 9 common RSNs. We found clear differences in how RSNs functionally respond to structural damage, namely that higher-order networks were more likely to experience changes in FC in response to structural damage (default mode R2 = 0.160-0.207, P < 0.001) than lower-order sensory networks (visual network 1 R2 = 0.001-0.007, P = 0.157-0.387). Our findings suggest that functional adaptability to structural damage depends on how involved the affected network is in higher-order processing.

Locus-Specific Enrichment Analysis of 5-Hydroxymethylcytosine Reveals Novel Genes Associated with Breast Carcinogenesis.

An imbalance in DNA methylation is a hallmark epigenetic alteration in cancer. The conversion of 5-methylcytosine (5-mC) to 5-hydroxymethyl cytosine (5-hmC), which causes the imbalance, results in aberrant gene expression. The precise functional role of 5-hydroxymethylcytosine in breast cancer remains elusive. In this study, we describe the landscape of 5-mC and 5-hmC and their association with breast cancer development. We found a distinguishable global loss of 5-hmC in the localized and invasive types of breast cancer that strongly correlate with TET expression. Genome-wide analysis revealed a unique 5-mC and 5-hmC signature in breast cancer. The differentially methylated regions (DMRs) were primarily concentrated in the proximal regulatory regions such as the promoters and UTRs, while the differentially hydroxymethylated regions (DhMRs) were densely packed in the distal regulatory regions, such as the intergenic regions (>-5 kb from TSSs). Our results indicate 4809 DMRs and 4841 DhMRs associated with breast cancer. Validation of nine 5-hmC enriched loci in a distinct set of breast cancer and normal samples positively correlated with their corresponding gene expression. The novel 5-hmC candidates such as TXNL1, and CNIH3 implicate a pro-oncogenic role in breast cancer. Overall, these results provide new insights into the loci-specific accumulation of 5-mC and 5-hmC, which are aberrantly methylated and demethylated in breast cancer.

Experimental and Computational Approaches for Non-CpG Methylation Analysis.

Cytosine methylation adjacent to adenine, thymine, and cytosine residues but not guanine of the DNA is distinctively known as non-CpG methylation. This CA/CT/CC methylation accounts for 15% of the total cytosine methylation and varies among different cell and tissue types. The abundance of CpG methylation has largely concealed the role of non-CpG methylation. Limitations in the early detection methods could not distinguish CpG methylation from non-CpG methylation. Recent advancements in enrichment strategies and high throughput sequencing technologies have enabled the detection of non-CpG methylation. This review discusses the advanced experimental and computational approaches to detect and describe the genomic distribution and function of non-CpG methylation. We present different approaches such as enzyme-based and antibody-based enrichment, which, when coupled, can also improve the sensitivity and specificity of non-CpG detection. We also describe the current bioinformatics pipelines and their specific application in computing and visualizing the imbalance of CpG and non-CpG methylation. Enrichment modes and the computational suites need to be further developed to ease the challenges of understanding the functional role of non-CpG methylation.

Lower cerebral arterial blood flow is associated with greater serum neurofilament light chain levels in multiple sclerosis patients.

BACKGROUND AND PURPOSE: Hypoperfusion, vascular pathology, and cardiovascular risk factors are associated with disease severity in multiple sclerosis (MS). We aimed to assess relationships between cerebral arterial blood flow (CABF) and serum neurofilament light chain (sNfL) as neuronal damage biomarkers. METHODS AND MATERIALS: Total CABF was measured in 137 patients (86 with clinically isolated syndrome/relapsing-remitting (RR) MS and 51 with progressive MS [PMS]) and 48 healthy controls using Doppler ultrasonography. sNfL was quantitated using a single-molecule assay (Simoa). Examination using 3.0-T magnetic resonance imaging (MRI) allowed quantification of T2 lesions and whole-brain volume (WBV). Multiple linear regression models determined the sNfL association with CABF after correction for demographic and MRI-derived variables. RESULTS: After adjustment for age, sex and body mass index (BMI), total CABF remained statistically significant and model comparisons showed that CABF explained an additional 2.6% of the sNfL variance (ß = -0.167, p = 0.044). CABF also remained significant in a stepwise regression model (ß = 0.18, p = 0.034) upon the inclusion of T2 lesion burden and WBV effects. Patients in the lowest CABF quartile (CABF ≤ 761 ml/min) had significantly higher sNfL levels (34.6 vs. 23.9 pg/ml, age and BMI-adjusted-p = 0.042) when compared to the highest quartile (CABF ≥ 1130 ml/min). CONCLUSION: Lower CABF is associated with increased sNfL in MS patients, highlighting the relationship between cerebral hypoperfusion and axonal pathology.

Time course of lesion-induced atrophy in multiple sclerosis.

BACKGROUND AND PURPOSE: White matter (WM) tract disruption impacts volume loss in connected deep gray matter (DGM) over 5 years in people with multiple sclerosis (PwMS). However, the timeline of this phenomenon remains poorly characterized. MATERIALS AND METHODS: Annual serial MRI for 181 PwMS was retrospectively analyzed from a 10-year clinical trial database. Annualized thalamic atrophy, DGM atrophy, and disruption of connected WM tracts were measured. For time series analysis, ~700 epochs were collated using a sliding 5-year window, and regression models predicting 1-year atrophy were applied to characterize the influence of new tract disruption from preceding years, while controlling for whole brain atrophy and other relevant factors. RESULTS: Disruptions of WM tracts connected to the thalamus were significantly associated with thalamic atrophy 1 year later (ß: 0.048-0.103). This effect was not observed for thalamic tract disruption concurrent with the time of atrophy nor for thalamic tract disruption preceding the atrophy by 2-4 years. Similarly, disruptions of white matter tracts connected to the DGM were significantly associated with DGM atrophy 1 year later (ß: 0.078-0.111), but not for tract disruption concurrent with, nor preceding the atrophy by 2-4 years. CONCLUSION: Increased rates of thalamic and DGM atrophy were restricted to 1 year following newly developed disruption in connected WM tracts. In research and clinical settings, additional gray matter atrophy may be expected 1 year following new lesion growth in connected white matter.

Patient-Reported Outcome Severity and Emotional Salience Network Disruption in Multiple Sclerosis.

BACKGROUND: Overall burden of white matter damage is associated with increased self-report fatigue severity in people with multiple sclerosis. However, a paradoxically opposite association was reported for white matter damage to tracts in specific subnetworks including the amygdala, temporal pole, and insula. Based on neuroanatomical principles and other data from the literature, we hypothesized that these results might be indicative of a broader relationship between damage to these subnetworks and impaired recognition of negative emotional salience central to patient-reported outcomes. OBJECTIVE: We examined whether damage in the same previously-identified subnetworks is also associated with lower self-report depressive symptoms, something which may be decreased in individuals with impaired recognition of negative emotional salience. Other patient characteristics were also explored. METHODS: In a cohort of 137 people with multiple sclerosis, we measured location-specific network white matter tract damage in the proposed negative emotional salience network, along with self-report severity of depressive symptoms and cognitive problems, personality characteristics, objective cognitive performance, and physical disability. We applied regression analyses, accounting for lesion burden, to explore the relationship between damage in the proposed negative emotional salience network and these factors. RESULTS: We found disruption within the negative emotional salience network is associated with lower self-report depressive symptoms (ß = -0.277, p = 0.036), cognitive complaints (r = -0.196, p = 0.024) and personality trait Neuroticism (r = -0.179, p = 0.042). In contrast, damage within this network was not significantly associated with objective cognitive processing speed, personality trait Openness, or physical disability. CONCLUSION: The identified network may be a generalizable network which corresponds to the recognition of negative emotional salience, but not to objective factors such as processing speed and physical disability. Damage to this network may paradoxically buffer against negative emotional perception of symptom severity, central to patient-reported outcomes.

Genome-wide methylome pattern predictive network analysis reveal mesenchymal stem cell's propensity to undergo cardiovascular lineage.

Mesenchymal stem cells (MSCs) differentiation toward cardiovascular lineage prediction using the global methylome profile will highlight its prospective utility in regenerative medicine. We examined the propensity prediction to cardiovascular lineage using 5-Aza, a well-known cardiac lineage inducer. The customized 180 K microarray was performed and further analysis of global differentially methylated regions by Ingenuity pathway analysis (IPA) in both MSCs and 5-AC-treated MSCs. The cluster enrichment tools sorted differentially enriched genes and further annotated to construct the interactive networks. Prediction analysis revealed pathways pertaining to the cardiovascular lineage found active in the native MSCs, suggesting its higher propensity to undergo cardiac, smooth muscle cell, and endothelial lineages in vitro. Interestingly, gene interaction network also proposed majorly stemness gene network NANOG and KLF6, cardiac-specific transcription factors GATA4, NKX2.5, and TBX5 were upregulated in the native MSCs. Furthermore, the expression of cardiovascular lineage specific markers such as Brachury, CD105, CD90, CD31, KDR and various forms of ACTIN (cardiac, sarcomeric, smooth muscle) were validated in native MSCs using real time PCR and immunostaining and blotting analysis. In 5-AC-treated MSCs, mosaic interactive networks were observed to persuade towards osteogenesis and cardiac lineage, indicating that 5-AC treatment resulted in nonspecific lineage induction in MSCs, while MSCs by default have a higher propensity to undergo cardiovascular lineage. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13205-021-03058-2.

Brain atrophy and lesion burden are associated with disability progression in a multiple sclerosis real-world dataset using only T2-FLAIR: The NeuroSTREAM MSBase study.

BACKGROUND: Methodological challenges limit the use of brain atrophy and lesion burden measures in the follow-up of multiple sclerosis (MS) patients on clinical routine datasets. OBJECTIVE: To determine the feasibility of T2-FLAIR-only measures of lateral ventricular volume (LVV) and salient central lesion volume (SCLV), as markers of disability progression (DP) in MS. METHODS: A total of 3,228 MS patients from 9 MSBase centers in 5 countries were enrolled. Of those, 2,875 (218 with clinically isolated syndrome, 2,231 with relapsing-remitting and 426 with progressive disease subtype) fulfilled inclusion and exclusion criteria. Patients were scanned on either 1.5 T or 3 T MRI scanners, and 5,750 brain scans were collected at index and on average after 42.3 months at post-index. Demographic and clinical data were collected from the MSBase registry. LVV and SCLV were measured on clinical routine T2-FLAIR images. RESULTS: Longitudinal LVV and SCLV analyses were successful in 96% of the scans. 57% of patients had scanner-related changes over the follow-up. After correcting for age, sex, disease duration, disability, disease-modifying therapy and LVV at index, and follow-up time, MS patients with DP (n = 671) had significantly greater absolute LVV change compared to stable (n = 1,501) or disability improved (DI, n = 248) MS patients (2.0 mL vs. 1.4 mL vs. 1.1 mL, respectively, ANCOVA p < 0.001, post-hoc pair-wise DP vs. Stable p = 0.003; and DP vs. DI, p = 0.002). Similar ANCOVA model was also significant for SCLV (p = 0.03). CONCLUSIONS: LVV-based atrophy and SCLV-based lesion outcomes are feasible on clinically acquired T2-FLAIR scans in a multicenter fashion and are associated with DP over mid-term.

Non-CpG methylation-a key epigenetic modification in cancer.

The methylation of cytosine residues that precede adenine/thymine or other cytosine nucleotides instead of guanine in DNA is known as non-CpG methylation. It is a pronounced epigenetic modification with a central role in gene regulation similar to CpG methylation. Due to technological limitations, the locus-specific role of non-CpG methylation was scarcely understood. At present, high-throughput analyses and improved enrichment methods can elucidate the role of genome-wide non-CpG methylation distributions. Although the functional basis of non-CpG methylation in regulating gene expression control is known, its role in cancer development is yet to be ascertained. This review sheds light on the possible mechanism of non-CpG methylation in embryos and developed tissues with a special focus on cancer development and progression. In particular, the maintenance and alteration of non-CpG methylation levels and the crucial factors that determine this level of non-CpG methylation and its functional role in cancer are discussed.

Quantifying disease pathology and predicting disease progression in multiple sclerosis with only clinical routine T2-FLAIR MRI.

BACKGROUND: Although quantitative measures from research-quality MRI provide a means to study multiple sclerosis (MS) pathology in vivo, these metrics are often unavailable in legacy clinical datasets. OBJECTIVE: To determine how well an automatically-generated quantitative snapshot of brain pathology, measured only on clinical routine T2-FLAIR MRI, can substitute for more conventional measures on research MRI in terms of capturing multi-factorial disease pathology and providing similar clinical relevance. METHODS: MRI with both research-quality sequences and conventional clinical T2-FLAIR was acquired for 172 MS patients at baseline, and neurologic disability was assessed at baseline and five-years later. Five measures (thalamus volume, lateral ventricle volume, medulla oblongata volume, lesion volume, and network efficiency) for quantifying disparate aspects of neuropathology from low-resolution T2-FLAIR were applied to predict standard research-quality MRI measures. They were compared in regard to association with future neurologic disability and disease progression over five years. RESULTS: The combination of the five T2-FLAIR measures explained most of the variance in standard research-quality MRI. T2-FLAIR measures were associated with neurologic disability and cognitive function five-years later (R2 = 0.279, p < 0.001; R2 = 0.382, p < 0.001), similar to standard research-quality MRI (R2 = 0.279, p < 0.001; R2 = 0.366, p < 0.001). They also similarly predicted disability progression over five years (%-correctly-classified = 69.8, p = 0.034), compared to standard research-quality MRI (%-correctly-classified = 72.4%, p = 0.022) in relapsing-remitting MS. CONCLUSION: A set of five T2-FLAIR-only measures can substitute for standard research-quality MRI, especially in relapsing-remitting MS. When only clinical T2-FLAIR is available, it can be used to obtain substantially more quantitative information about brain pathology and disability than is currently standard practice.

Identification of novel dysregulated circular RNAs in early-stage breast cancer.

Breast cancer is a major cause of cancer-related death in women worldwide. Non-coding RNAs are a potential resource to be used as an early diagnostic biomarker for breast cancer. Circular RNAs are a recently identified group of non-coding RNA with a significant role in disease development with potential utility in diagnosis/prognosis in cancer. In this study, we identified 26 differentially expressed circular RNAs associated with early-stage breast cancer. RNA sequencing and two circRNA detection tools (find_circ and DCC) were used to understand the circRNA expression signature in breast cancer. We identified hsa_circ_0006743 (circJMJD1C) and hsa_circ_0002496 (circAPPBP1) to be significantly up-regulated in early-stage breast cancer tissues. Co-expression analysis identified four pairs of circRNA-miRNA (hsa_circ_0023990 : hsa-miR-548b-3p, hsa_circ_0016601 : hsa_miR-1246, hsa_circ_0001946 : hsa-miR-1299 and hsa_circ_0000117:hsa-miR-502-5p) having potential interaction. The miRNA target prediction and network analysis revealed mRNA possibly regulated by circRNAs. We have thus identified circRNAs of diagnostic implications in breast cancer and also observed circRNA-miRNA interaction which could be involved in breast cancer development.

Clinical feasibility of longitudinal lateral ventricular volume measurements on T2-FLAIR across MRI scanner changes.

BACKGROUND: Greater brain atrophy is associated with disability progression (DP) in patients with multiple sclerosis (PwMS). However, methodological challenges limit its routine clinical use. OBJECTIVE: To determine the feasibility of atrophy measures as markers of DP in PwMS scanned across different MRI field strengths. METHODS: A total of 980 PwMS were scanned on either 1.5 T or 3.0 T MRI scanners. Demographic and clinical data were retrospectively collected, and the presence of DP was determined according to standard clinical trial criteria. Lateral ventricular volume (LVV) change was measured with the NeuroSTREAM technique on clinical routine T2-FLAIR images. Percent brain volume change (PBVC) was measured using SIENA and ventricular cerebrospinal fluid (vCSF) % change was measured using VIENA and SIENAX algorithms on 3D T1-weighted images (WI). Stable vs. DP PwMS were compared using analysis of covariance (ANCOVA). Mixed modeling determined the effect of MRI scanner change on MRI-derived atrophy measures. RESULTS: Longitudinal LVV analysis was successful in all PwMS. SIENA-based PBVC and VIENA-based changes failed in 37.6% of cases, while SIENAX-based vCSF failed in 12.9% of cases. PwMS with DP (n = 241) had significantly greater absolute (20.9% vs. 8.7%, d = 0.66, p < 0.001) and annualized LVV % change (4.1% vs. 2.3%, d = 0.27, p < 0.001) when compared to stable PwMS (n = 739). In subjects with both analyses available, both 3D-T1 and T2-FLAIR-based analyses differentiated PwMS with DP (n = 149). However, only NeuroSTREAM and VIENA-based LVV/vCSF were able to show greater atrophy in PwMS that were scanned on different scanners. PBVC and SIENAX-based vCSF % changes were significantly affected by scanner change (Beta = -0.16, t-statistics = -2.133, p = 0.033 and Beta = -2.08, t-statistics = -4.084, p < 0.001), whereas no MRI scanner change effects on NeuroSTREAM-based PLVVC and VIENA-based vCSF % change were noted. CONCLUSIONS: LVV-based atrophy on T2-FLAIR is a clinically relevant measure in spite of MRI scanner changes and mild disability levels.

Leptomeningeal, dura mater and meningeal vessel wall enhancements in multiple sclerosis.

BACKGROUND: Leptomeningeal contrast enhancement (LMCE) has previously shown potential to be an indirect marker for leptomeningeal inflammation in multiple sclerosis (MS). Dura mater (DME), inclusive falx cerebri (FCE) enhancement and meningeal vessel wall enhancement (VWE) represent two other meningeal enhancement patterns in MS that have not been extensively studied. OBJECTIVES: To investigate the frequency of LMCE, DME/FCE and VWE in patients with MS and their associations with demographic, clinical and MRI characteristics in a longitudinal retrospective study. METHODS: 217 MS patients (193 relapsing-remitting MS, 24 progressive MS) were assessed at baseline and over 18 months follow-up using 3T 3D FLAIR pre- and post-contrast and subtraction images. Lesion and brain volume outcomes were additionally calculated. Analyses were adjusted for age, and corrected for multiple comparisons. RESULTS: LMCE and VWE frequency was associated with higher age (p<0.02), but the presence of DME/FCE was not (p=0.402). 24% of MS patients revealed LMCE and VWE, respectively, and 47% showed DME/FCE. Presence of LMCE, VWE and DME/FCE was not significantly associated with clinical or imaging markers of disease severity. All three patterns of meningeal enhancement showed a high persistence in shape and size at follow-up. CONCLUSIONS: LMCE, DME/FCE and VWE can be identified by gadolinium-enhanced 3D FLAIR MR imaging. Meningeal enhancement is associated with higher age. DME/FCE is the most frequent meningeal enhancement pattern in MS, however further case-control studies should determine whether this represents abnormal lymphatic drainage in these patients or is an age-dependent physiologic phenomenon.

Subcutaneous anti-CD20 antibody treatment delays gray matter atrophy in human myelin oligodendrocyte glycoprotein-induced EAE mice.

BACKGROUND: The human myelin oligodendrocyte glycoprotein-induced experimental autoimmune encephalomyelitis (huMOG-EAE) model, generates B-cell driven demyelination in mice, making it a suitable multiple sclerosis model to study B cell depletion. OBJECTIVES: We investigated the effect of subcutaneous anti-CD20 antibody treatment on huMOG-EAE gray matter (GM) pathology. METHODS: C57Bl/6, 8-week old mice were immunized with 200 huMOG1-125 and treated with 50 µg/mouse of anti-CD20 antibody (n = 16) or isotype control (n = 16). Serial brain volumetric 9.4 T MRI scans was performed at baseline, 1 and 5 wkPI. Disease severity was measured by clinical disability score (CDS) and performance on rotarod test. RESULTS: Anti-CD20 antibody significantly reduced brain volume loss compared with the isotype control across all timepoints longitudinally in the basal ganglia (p = 0.01), isocortex (p = 0.025) and thalamus (p = 0.023). The CDS was reduced significantly with anti-CD20 antibody vs. the isotype control at 3 (p = 0.003) and 4 (p = 0.03) wkPI, while a trend was observed at 5 (p = 0.057) and 6 (p = 0.086) wkPI. Performance on rotarod was also improved significantly at 3 (p = 0.007) and 5 (p = 0.01) wkPI compared with the isotype control. At cellular level, anti-CD20 therapy suppressed the percentage of proliferative nuclear antigen positive microglia in huMOG-EAE isocortex (p = 0.016). Flow cytometry confirmed that anti-CD20 antibody strongly depleted the CD19-expressing B cell fraction in peripheral blood mononuclear cells, reducing it from 39.7% measured in isotype control to 1.59% in anti-CD20 treated mice (p < 0.001). CONCLUSIONS: Anti-CD20 antibody treatment delayed brain tissue neurodegeneration in GM, and showed clinical benefit on measures of disease severity in huMOG-EAE mice.

Diagnosis of depression in multiple sclerosis is predicted by frontal-parietal white matter tract disruption.

BACKGROUND: Persons with multiple sclerosis (PwMS) are at an elevated risk of depression. Decreased Conscientiousness may affect patient outcomes in PwMS. Low Conscientiousness has a strong correlation with depression. Previous work has also reported that white matter (WM) tract disruption in frontal-parietal networks explains reduced Conscientiousness in PwMS. OBJECTIVE: We hypothesized that Conscientiousness-associated WM tract disruption predicts new-onset depression over 5 years in PwMS and evaluated this by assessing the predictive power of mean Conscientiousness associated frontal-parietal network (CFPN) disruption in PwMS for clinically diagnosed depression over 5 years. METHODS: This longitudinal retrospective analysis included 53 PwMS who were not previously diagnosed as depressed. All participants underwent structural MRI. Medical records were reviewed to evaluate diagnosis of depression for these patients over 5 years. WM tract damage between pairs of gray matter regions in the CFPN was measured using diffusion imaging. The relationship between CFPN disruption and depression was analyzed using logistic regression. RESULTS: Participants with MS had a mean age of 46.0 years (SD = 11.2). 22.6% (n = 12) acquired a diagnosis of clinical depression over the 5-year period. Baseline disruption in the CFPN was a significant predictor (ROC AUC = 61.8%). of new-onset clinical depression, accounting for age, sex, lateral ventricular volume, disease modifying treatment, and lesion volume. CONCLUSION: Baseline CFPN disruption is associated with progression to clinical depression over 5 years in PwMS. Development of new WM pathology within this network may be a risk factor for depression.

Late onset multiple sclerosis is associated with more severe ventricle expansion.

BACKGROUND: Late-onset multiple sclerosis (LOMS) is associated with faster disability progression than persons with adult-onset MS (PwAOMS). The differences in brain atrophy are currently unknown. OBJECTIVES: To determine MRI-derived atrophy rates in persons with late-onset MS (PwLOMS) and compare them to an age-matched and disease duration-matched sample of PwAOMS. METHODS: 870 persons with MS (290 PwLOMS, 290 age-matched PwAOMS, and 290 disease duration-matched PwAOMS), and 150 healthy controls (HCs), were followed for 5 years and 3 years, respectively. Cross-sectional and longitudinal measures of T2-lesion volume (LV), lateral ventricular volume (LVV) and whole brain volume (WBV) were derived. Expanded Disability Status Scale (EDSS) and Multiple Sclerosis Severity Score (MSSS) were calculated. Both analyses were corrected for false discovery rate. RESULTS: Persons with MS exhibited significantly greater annualized WBV loss (-0.88% vs. -0.38%, p<0.001) and annualized LVV expansion (3.1% vs. 1.7%, p=0.002) when compared to HCs. PwLOMS had significantly higher baseline and follow-up median MSSS when compared to both age-matched and disease duration-matched PwAOMS (p<0.026). PwLOMS showed significantly greater percent LVV change (14.3% vs. 9.3% p=0.001) and greater annualized percent LVV change (4.1% vs. 1.6%, p<0.001) compared to age-matched PwAOMS. CONCLUSION: PwLOMS had higher MSSS and greater ventricle expansion when compared to PwAOMS.

Longitudinal Magnetic Resonance Imaging of Cerebral Microbleeds in Multiple Sclerosis Patients.

We hypothesized that cerebral microbleeds (CMBs) in multiple sclerosis (MS) patients will be detected with higher prevalence compared to healthy controls (HC) and that quantitative susceptibility mapping (QSM) will help remove false positives seen in susceptibility weighted imaging (SWI). A cohort of 100 relapsing remitting MS subjects scanned at 3T were used to validate a set of CMB detection guidelines specifically using QSM. A second longitudinal cohort of 112 MS and 25 HCs, also acquired at 3T, was reviewed across two time points. Both cohorts were imaged with SWI and fluid attenuated inversion recovery. Fourteen subjects in the first cohort (14%, 95% CI 8-21%) and twenty-one subjects in the second cohort (18.7%, 95% CI 11-27%) had at least one CMB. The combined information from SWI and QSM allowed us to discern stable CMBs and new CMBs from potential mimics and evaluate changes over time. The longitudinal results demonstrated that longer disease duration increased the chance to develop new CMBs. Higher age was also associated with increased CMB prevalence for MS and HC. We observed that MS subjects developed new CMBs between time points, indicating the need for longitudinal quantitative imaging of CMBs.

Relationships Among Circulating Levels of Hemostasis Inhibitors, Chemokines, Adhesion Molecules, and MRI Characteristics in Multiple Sclerosis.

Background: Several studies suggested cross talk among components of hemostasis, inflammation, and immunity pathways in the pathogenesis, neurodegeneration, and occurrence of cerebral microbleeds (CMBs) in multiple sclerosis (MS). Objectives: This study aimed to evaluate the combined contribution of the hemostasis inhibitor protein C (PC) and chemokine C-C motif ligand 18 (CCL18) levels to brain atrophy in MS and to identify disease-relevant correlations among circulating levels of hemostasis inhibitors, chemokines, and adhesion molecules, particularly in CMB occurrence in MS. Methods: Plasma levels of hemostasis inhibitors (ADAMTS13, PC, and PAI1), CCL18, and soluble adhesion molecules (sNCAM, sICAM1, sVCAM1, and sVAP1) were evaluated by multiplex in 138 MS patients [85 relapsing-remitting (RR-MS) and 53 progressive (P-MS)] and 42 healthy individuals (HI) who underwent 3-T MRI exams. Association of protein levels with MRI outcomes was performed by regression analysis. Correlations among protein levels were assessed by partial correlation and Pearson's correlation. Results: In all patients, regression analysis showed that higher PC levels were associated with lower brain volumes, including the brain parenchyma (p = 0.002), gray matter (p < 0.001), cortex (p = 0.001), deep gray matter (p = 0.001), and thalamus (p = 0.001). These associations were detectable in RR-MS but not in P-MS patients. Higher CCL18 levels were associated with higher T2-lesion volumes in all MS patients (p = 0.03) and in the P-MS (p = 0.003). In the P-MS, higher CCL18 levels were also associated with lower volumes of the gray matter (p = 0.024), cortex (p = 0.043), deep gray matter (p = 0.029), and thalamus (p = 0.022). PC-CCL18 and CCL18-PAI1 levels were positively correlated in both MS and HI, PC-sVAP1 and PAI1-sVCAM1 only in MS, and PC-sICAM1 and PC-sNCAM only in HI. In MS patients with CMBs (n = 12), CCL18-PAI1 and PAI1-sVCAM1 levels were better correlated than those in MS patients without CMBs, and a novel ADAMTS13-sVAP1 level correlation (r = 0.78, p = 0.003) was observed. Conclusions: Differences between clinical phenotype groups in association of PC and CCL18 circulating levels with MRI outcomes might be related to different aspects of neurodegeneration. Disease-related pathway dysregulation is supported by several protein level correlation differences between MS patients and HI. The integrated analysis of plasma proteins and MRI measures provide evidence for new relationships among hemostasis, inflammation, and immunity pathways, relevant for MS and for the occurrence of CMBs.

High density lipoprotein cholesterol and apolipoprotein A-I are associated with greater cerebral perfusion in multiple sclerosis.

BACKGROUND: The pathophysiological mechanisms underlying the associations of multiple sclerosis (MS) neurodegeneration serum cholesterol profiles is currently unknown. OBJECTIVE: To determine associations between lipid profile measures and cerebral perfusion-based indices in MS patients. METHODS: Seventy-seven MS patients underwent 3 T MRI. Cerebral blood volume (CBV), time-to-peak (TTP) and mean transit time (MTT) measures were computed from dynamic susceptibility contrast (DSC) perfusion-weighted imaging (PWI) for normal-appearing brain tissue (NABT), GM, cortex, deep gray matter (DGM) and thalamus. Total cholesterol, low and high-density lipoprotein cholesterol (LDL-C and HDL-C) and the apolipoproteins (Apo), ApoA-I, ApoA-II, ApoB, ApoC-II and ApoE levels were measured in plasma. Age and body mass index (BMI)-adjusted correlations were used to assess the associations between PWI and lipid profile measures. RESULTS: Higher HDL-C levels were associated with shorter MTT, which are indicative of greater perfusion, in NABT (p = 0.012), NAWM (p = 0.021), GM (p = 0.009), cortex (p = 0.014), DGM p = 0.015; and thalamus p = 0.015). The HDL-C-associated apolipoproteins, ApoA-I and ApoA-II, were associated with shorter MTT of the same brain regions (all p < 0.028). HDL-C and ApoA-I levels were also associated with shorter TTP, indicative of faster cerebral blood delivery. ApoC-II was associated with lower nCBV of the GM and cortex (p = 0.035 and p = 0.014, respectively). CONCLUSION: The HDL pathway is associated with better global brain perfusion and faster cerebral blood delivery as measured by shorter MTT and TTP, respectively. ApoC-II may be associated with lower cortical and DGM perfusion.