CD24 as a genetic modifier of disease progression in multiple sclerosis in Argentinean patients

MS and Disability Progression in Latin America, Africa, Asia and the Middle East: A Systematic Review

BACKGROUND

There is evidence of an increased prevalence and disease burden of Multiple Sclerosis (MS) in parts of the world where the risk was once considered low, such as Latin America (LA), Sub-Saharan Africa, Asia and the Middle East-North Africa (MENA). Despite the growing number of clinical reports, the phenotype and course of MS in these regions remains understudied compared with Europe and North America. We aimed to investigate MS phenotypes and long-term clinical outcomes across these regions.

METHOD

A Boolean search of the medical literature was conducted between January 1980 and April 30, 2020. PubMed, SCOPUS, Global Health, and the Cochrane databases, were used to identify all relevant citations. Articles were collated and managed on Covidence® software. We independently appraised the articles for meeting study criteria and for quality using the Critical Appraisal Skills Program (CASP) and the Specialist Unit for Review Evidence (SURE) system.

RESULTS

A total of 1,639 studies were imported for screening. After removing 545 duplicates, two authors assessed 1,094 abstracts and selected 515 for full-text screening. 72 articles met study criteria, including 19 studies from LA, 4 from sub-Saharan Africa, 24 from Asia and 25 from MENA. The overall sex ratio was 2.5:1 (female: male). Disability was assessed using the Expanded Disability Status Scale (EDSS). Longitudinal disability progression and time to standard endpoints was compared by region and with relevant Western reports. Patients with MS living in the MENA region appear to reach disability milestones faster than those in the Western world, although this finding is not uniform. South Asia shows distinct disability features compared with East Asia, more closely resembling those of the West. Disease morbidity in East Asia appears more benign than in the West after careful exclusion of neuromyelitis optica spectrum disorder cases. Populations in LA tend to have similar MS features to the Western world, but some exceptions exist, including African descendants that reach disability milestones earlier. Using all studies with appropriate survival analysis, the mean time to EDSS 6.0 was 16.97 years with a heterogeneity index of 24.59.

CONCLUSION

The clinical phenotypes and disability progression of MS in LA, Africa, Asia and the MENA region have similarities to Western MS. In some regions and subpopulations there is evidence of a more aggressive course, possibly due to a combination of genetic and environmental factors. More population-based longitudinal data are needed, particularly in Sub-Saharan Africa.

A CD24-p53 axis contributes to African American prostate cancer disparities

BACKGROUND

Using a functional analysis of prostate cancer cells, we found a CD24-dependent inactivation of mutant p53, but the clinical significance of this observation remained uncertain. Here, we validated these results with samples of human prostate cancer and explored the role of a CD24-p53 axis in racial disparities of prostate cancer.

METHODS

Samples of formalin-fixed, paraffin-embedded prostate cancer from 141 European Americans (EAs) and 147 African Americans (AAs) in two independent sample cohorts were assessed for protein expression of CD24, mutant p53, mouse double minute 2 human homolog (MDM2), and cyclin dependent kinase inhibitor 2A (ARF) using immunohistochemical analyses. All samples were analyzed for TP53^R175H and TP53^R273H .

RESULTS

CD24, mutant p53, MDM2, and ARF proteins were expressed in 55%, 24%, 39%, and 68% of prostate cancer samples, respectively. CD24 and mutant p53 were present more frequently in late-stage and metastatic prostate cancer. The presence of CD24 was associated with a greater than fourfold risk of metastasis, which included lymph node and distant metastases. H score analysis showed positive correlations of CD24 expression with mutant p53 (r = .308, P < .001) and MDM2 (r = .227, P = .004). There was a negative correlation for CD24 with ARF (r = -.280, P < .001). A racial disparity was evident for CD24 (AAs/EAs: 64% vs 47%; P = .004) but not for mutant p53 (AA/EA: 28% vs 21%; P = .152). In 32 CD24⁺ /mutant p53⁺ cases, a TP53^R273H mutation was found in five cases, but no TP53^R175H mutation was found.

CONCLUSION

The CD24-p53 axis may contribute to aggressive and metastatic prostate cancers, especially those of AAs. This observation enhances understanding of the pathogenesis of prostate cancer and its associated racial disparities.

Association between CD24 Ala/Val polymorphism and multiple sclerosis risk: A meta analysis

BACKGROUND

The aim of this study was to explore the association between CD24 Ala/Val polymorphism and susceptibility of multiple sclerosis (MS).

METHODS

A comprehensive literature search for relevant studies was performed on google scholar, PubMed, Web of science, Embase, the Chinese National Knowledge Infrastructure and the Chinese Biology Medicine. This meta-analysis was conducted using the STATA 11.0 software and the pooled odds ratio with 95% confidence interval was calculated.

RESULTS

Seven case-control studies were included in this meta-analysis. The results showed significant association between CD24 Ala/Val polymorphism and susceptibility to MS. Stratified analysis by areas also showed significant association in Asians. However, no association was found in Europeans.

CONCLUSION

This study suggested that the CD24 Val allele was associated with an increased risk of MS and larger-scale studies of populations are needed to explore the role of CD24 Ala/Val polymorphism during the pathogenesis of MS.

CD24 aggravates acute liver injury in autoimmune hepatitis by promoting IFN-γ production by CD4+ T cells

The T-cell-mediated immune response is implicated in many clinical hepatic injuries, such as autoimmune hepatitis and acute virus hepatitis. CD24 is widely expressed by different immune cells and plays an important role in the pathogenesis of many autoimmune diseases. However, the role of CD24 in T-cell-mediated liver injury has not been elucidated until now. Here we showed that CD24 deficiency protects mice from concanavalin A (ConA)-induced fulminant liver injury by reducing serum interferon-γ (IFN-γ) levels. CD24 expression by hepatic T cells was markedly increased following ConA challenge. Moreover, decreased IFN-γ production by hepatic CD4⁺ T cells in CD24-deficient mice was detected, which was correlated with downregulated phosphorylation of STAT1 in hepatic tissue. In vitro experiments also supported the conclusion that CD24 deficiency impaired IFN-γ production by CD4⁺ T cells following ConA, CD3/CD28 and phorbol myristate acetate/ionomycin stimulation. Our study suggests that CD24 deficiency confers hepatoprotection by decreasing CD4⁺ T-cell-dependent IFN-γ production in vivo, which suggests that CD24 might be a potential target molecule for reducing clinical hepatitis.

Silencing of CD24 Enhances the PRIMA-1-Induced Restoration of Mutant p53 in Prostate Cancer Cells

PURPOSE

In prostate cancer cells, there is CD24-dependent inactivation of mutant p53, but the mechanism and its significance remain largely unknown. Here, we validated this observation and explored the therapeutic potential of targeting CD24 in TP53 mutant prostate cancer cells.

EXPERIMENTAL DESIGN

Overall, 553 prostate cancers (522 formalin-fixed paraffin-embedded and 31 frozen tissues) were assessed for protein or mRNA expression of CD24 and TP53 The effects of CD24 on p53-dependent transcriptional regulation, cancer cell growth, the cell cycle, apoptosis, and mutant p53 restoration were also determined.

RESULTS

As determined with three sample cohorts, CD24 and p53 were not expressed in prostate epithelial cells but in prostate cancer cells in 48% of cases for CD24 and 16% of cases for p53 (mutant form). Expressions of CD24 and mutant p53 were more frequently observed in late-stage and metastatic prostate tumors. Mutant p53 accompanied with CD24 was expressed in most cases (91.6%, 76/83). Silencing of CD24 increased the transcriptional activity of p53 target genes, such as CDKNA1, VDR, and TP53INP1, leading to suppression of p53-dependent cell growth, cell-cycle arrest, and apoptosis in most TP53-mutant prostate cancer cells. Silencing of CD24 enhanced restoration of PRIMA-1-induced mutant p53 in endogenous TP53(P223L/V274F) DU145 cells and in PC3 cells transfected with TP53(R273H) CONCLUSIONS: In human prostate cancers, there is CD24-dependent inactivation of mutant p53. The coexpression of CD24 and p53 may help identify aggressive cancers. Targeting CD24 provides a strategy to enhance mutant p53-restoring therapies, especially in patients with TP53(R273H) prostate cancer. Clin Cancer Res; 22(10); 2545-54. ©2015 AACR.

Polymorphisms of the CD24 Gene Are Associated with Risk of Multiple Sclerosis: A Meta-Analysis

CD24 is a cell-surface protein mainly expressed in cells of the immune and central nervous system (CNS), cells that play a critical role in the development of multiple sclerosis (MS). In the current study, we investigated four polymorphisms of the CD24 gene regarding their associations with MS. To this end, univariate and multivariate meta-analysis were applied along with modifications to include data from family-trios so as to increase the robustness of the meta-analysis. We found that the polymorphism 226 C>T (Ala57Val) of the CD24 gene is associated with MS according to the recessive mode of inheritance (odds ratio = 1.75; 95% CI: 1.09, 2.81). Moreover, the 1527–1528 TG>del polymorphism is inversely associated with MS according to the dominant mode of inheritance (odds ratio = 0.57; 95% CI 0.39, 0.83). Conversely, the 1056 A>G and 1626 A>G polymorphisms were not found to be associated with MS. We conclude that the CD24 226 C>T polymorphism increases the risk of MS, while the 1527–1528 TG>del polymorphism seems to have a protective role against MS, suggesting that these two polymorphisms can be used as predictive biomarkers for MS development.

Association between the CD24 Ala57Val polymorphism and risk for multiple sclerosis and systemic lupus erythematosus: a meta-analysis

The cluster of differentiation 24 (CD24) Ala57Val polymorphism has been implicated as a risk factor for multiple sclerosis (MS) and systemic lupus erythematosus (SLE); however, genetic studies have produced controversial results. A meta-analysis was performed on this topic. We used odds ratio (OR) and 95% confidence interval (95% CI) to investigate the strength of association. Eleven studies from nine publications consisting of 2466 cases and 2650 controls were included. The results suggested that the CD24 Val/Val genotypes were associated with an increased risk of MS in all study subjects and Caucasians (OR = 2.28, 95% CI: 1.68–3.10, P_z < 0.001 and OR = 2.30, 95% CI: 1.66–3.20, P_z < 0.001, respectively). Sensitivity analysis showed that no individual study was found to be significantly biasing the pooled results. Although meta-analysis also suggested an association between the CD24 Val/Val genotypes and SLE risk in Caucasians (OR = 1.71, 95% CI: 1.31–2.24, P_z < 0.001), sensitivity analysis demonstrated that the association was not statistically significant after removing a Spanish study. In conclusion, this meta-analysis suggests that the CD24 Ala57Val polymorphism is associated with an increased risk of MS in Caucasians. However, the available evidence is not sufficient to support an association between the CD24 Ala57Val polymorphism and SLE risk.

Intracellular CD24 disrupts the ARF-NPM interaction and enables mutational and viral oncogene-mediated p53 inactivation

CD24 is overexpressed in nearly 70% human cancers, whereas TP53 is the most frequently mutated tumour-suppressor gene that functions in a context-dependent manner. Here we show that both targeted mutation and short hairpin RNA (shRNA) silencing of CD24 retard the growth, progression and metastasis of prostate cancer. CD24 competitively inhibits ARF binding to NPM, resulting in decreased ARF, increase MDM2 and decrease levels of p53 and the p53 target p21/CDKN1A. CD24 silencing prevents functional inactivation of p53 by both somatic mutation and viral oncogenes, including the SV40 large T antigen and human papilloma virus 16 E6-antigen. In support of the functional interaction between CD24 and p53, in silico analyses reveal that TP53 mutates at a higher rate among glioma and prostate cancer samples with higher CD24 mRNA levels. These data provide a general mechanism for functional inactivation of ARF and reveal an important cellular context for genetic and viral inactivation of TP53.

P53 is a tumour suppressor that is frequently mutated or downregulated in cancer. Here, Wang et al. show that CD24, a molecule frequently overexpressed in cancer, promotes p53 degradation by disrupting a regulatory ARF–MDM2 interaction, and silencing CD24 prevents the downregulation of p53.

Selectins and their ligands as potential immunotherapeutic targets in neurological diseases

Selectins are a family of adhesion receptors that bind to highly glycosylated molecules expressed on the surface of leukocytes and endothelial cells. The interactions between selectins and their ligands control tethering and rolling of leukocytes on the vascular wall during the process of leukocyte migration into the tissues under physiological and pathological conditions. In recent years, it has been shown that leukocyte recruitment in the CNS plays a pivotal role in diseases such as multiple sclerosis, ischemic stroke, epilepsy and traumatic brain injury. In this review, we discuss the role of selectins in leukocyte–endothelial interactions in the pathogenesis of neurological diseases, highlighting new findings suggesting that selectins and their ligands may represent novel potential therapeutic targets for the treatment of CNS diseases.

Genetic association analysis and meta-analysis of imputed SNPs in longitudinal studies

In this paper we propose a new method to analyze time-to-event data in longitudinal genetic studies. This method address the fundamental problem of incorporating uncertainty when analyzing survival data and imputed single-nucleotide polymorphisms (SNPs) from genome-wide association studies (GWAS). Our method incorporates uncertainty in the likelihood function, the opposite of existing methods that incorporate the uncertainty in the design matrix. Through simulation studies and real data analyses, we show that our proposed method is unbiased and provides powerful results. We also show how combining results from different GWAS (meta-analysis) may lead to wrong results when effects are not estimated using our approach. The model is implemented in an R package that is designed to analyze uncertainty not only arising from imputed SNPs, but also from copy number variants.