Associations of NINJ2 sequence variants with incident ischemic stroke in the Cohorts for Heart and Aging in Genomic Epidemiology (CHARGE) consortium

Genetic polymorphisms of MRPS30-DT and NINJ2 may influence lung cancer risk

Lung cancer is one of the malignant tumors, and genetic background is a risk factor in lung cancer that cannot be neglected. In this study, we aimed to find out the effect of MRPS30-DT and NINJ2 variants on lung cancer risk. In this study, the seven selected single-nucleotide polymorphisms (SNPs) of MRPS30-DT and NINJ2 were genotyped in 509 lung cancer patients and 501 healthy controls based on the Agena MassARRAY platform. Odds ratios and 95% confidence intervals were calculated by logistic regression analysis to evaluate association between gene polymorphisms and lung cancer risk. False-positive report probability was also used to assess false-positive results. Furthermore, the interaction between SNPs was analyzed by multifactor dimensionality reduction to predict lung cancer risk. We identified the genotype TA of rs16901963 (T < A) in MRPS30-DT as a protective factor against lung cancer, while rs16901963-TT was significantly associated with an increased risk of lung cancer. We also revealed that the effect of MRPS30-DT and NINJ2 variants on the risk of lung cancer was dependent on age, gender, smoking, and drinking status. In conclusion, this study first proved that MRPS30-DT and NINJ2 variants played important roles in affecting the susceptibility to lung cancer.

Involvement of NINJ2 Protein in Inflammation and Blood-Brain Barrier Transmigration of Monocytes in Multiple Sclerosis

Multiple sclerosis (MS) is an inflammatory neurodegenerative disorder of the central nervous system (CNS). The migration of immune cells into the CNS is essential for its development, and plasma membrane molecules play an important role in triggering and maintaining the inflammation. We previously identified ninjurin2, a plasma membrane protein encoded by NINJ2 gene, as involved in the occurrence of relapse under Interferon-β treatment in MS patients. The aim of the present study was to investigate the involvement of NINJ2 in inflammatory conditions and in the migration of monocytes through the blood-brain barrier (BBB). We observed that NINJ2 is downregulated in monocytes and in THP-1 cells after stimulation with the pro-inflammatory cytokine LPS, while in hCMEC/D3 cells, which represent a surrogate of the BBB, LPS stimulation increases its expression. We set up a transmigration assay using an hCMEC/D3 transwell-based model, finding a higher transmigration rate of monocytes from MS subjects compared to healthy controls (HCs) in the case of an activated hCMEC/D3 monolayer. Moreover, a positive correlation between NINJ2 expression in monocytes and monocyte migration rate was observed. Overall, our results suggest that ninjurin2 could be involved in the transmigration of immune cells into the CNS in pro-inflammatory conditions. Further experiments are needed to elucidate the exact molecular mechanisms.

Functional rare variant in a C/EBP beta binding site in NINJ2 gene increases the risk of coronary artery disease

Objective: NINJ2 regulates activation of vascular endothelial cells, and genome-wide association studies showed that variants in NINJ2 confer risk to stroke. However, whether variants in NINJ2 are associated with coronary artery disease (CAD) is unknown.

Methods: We genotyped rs34166160 in NINJ2 in two independent Chinese GeneID populations which included 2,794 CAD cases and 4,131 controls, and performed genetics association studies. Functional studies were also performed to reveal the mechanisms.

Results: Allele rs34166160 significantly confers risk to CAD in the GeneID Hubei population which contained 1,440 CAD cases and 2,660 CAD-free controls (observed P_-obs = 6.39 × 10⁻³ with an odds ratio (OR) was 3.39, adjusted P_-adj = 8.12 × 10⁻³ with an OR of 3.10). The association was replicated in another population, GeneID Shandong population contained 1,354 CAD cases and 1,471 controls (P_-obs = 3.33 × 10⁻³ with an OR of 3.14, P_-adj = 0.01 with an OR of 2.74). After combining the two populations, the association was more significant (P_-obs = 1.57 × 10⁻⁵ with an OR of 3.58, P_-adj = 3.41 × 10⁻⁴ with an OR of 2.80). In addition, we found that rs34166160 was associated with the mRNA expression level of NINJ2 and the flanking region of rs34166160 can directly bind with transcriptional factor CCAAT-box/enhancer-binding protein beta, and the risk A allele has more transcription activity than non-risk C allele with or without LPS in HUVEC cells.

Conclusions: Our study demonstrates that the functional rare variant rs34166160 in NINJ2 confers risk to CAD for the first time, and these findings further expand the range of the pathology of CAD and atherosclerosis.

A single nucleotide polymorphism within Ninjurin 2 is associated with risk of multiple sclerosis

Multiple sclerosis (MS) is a devastating inflammatory disease of the central nervous system (CNS) associated with loss of myelin sheaths. The role of Schwan cells in the remyelination of MS lesions has been documented. However, the detailed steps of this process are unknown. Ninjurin 2 (NINJ2) encodes an adhesion protein with high expression in Schwann cells adjoining the distal piece of injured nerve. Based on the role of this protein in neurite outgrowth, it might participate in the process of nerve regeneration after nerve damage. In the present study, we genotyped two NINJ2 single nucleotide polymorphisms (SNPs) namely rs11833579 and rs3809263 in a population of Iranian patients with MS as well as healthy individuals. The frequency of T allele of the rs3809263 was significantly higher in MS patients compared with healthy subjects (OR (95% CI) = 1.33 (1.08-1.63), adjusted P value = 0.01). TT genotype of this SNP was associated with MS risk compared with CC genotype (OR (95% CI) = 2.22 (1.37-3.57), adjusted P value = 0.009). Moreover, the rs3809263 was associated with MS risk in recessive model (OR (95% CI) = 2.09 (1.33-3.31), adjusted P value = 0.003). There were no significant difference in the alleles and genotypes frequencies of rs11833579 between cases and controls. The current research suggests contribution of NINJ2 in the pathogenesis of MS and warrants further studies for elaboration of the underlying mechanism of such contribution.

A pharmacogenetic study implicates NINJ2 in the response to Interferon-β in multiple sclerosis

BACKGROUND

Multiple sclerosis (MS) is a disease in which biomarker identification is fundamental to predict response to treatments and to deliver the optimal drug to patients. We previously found an association between rs7298096, a polymorphism upstream to the NINJ2 gene, and the 4-year response to interferon-β (IFNβ) treatment in MS patients.

OBJECTIVES

To analyse the association between rs7298096 and time to first relapse (TTFR) during IFNβ therapy in MS patients and to better investigate its functional role.

METHODS

Survival analysis was applied in three MS cohorts from different countries (n = 1004). We also studied the role of the polymorphism on gene expression using GTEx portal and a luciferase assay. We interrogated GEO datasets to explore the relationship between NINJ2 expression, IFNβ and TTFR.

RESULTS

Rs7298096_AA patients show a shorter TTFR than rs7298096_G-carriers (P_{meta-analysis} = 3 × 10^-4, hazard ratio = 1.41). Moreover, rs7298096_AA is associated with a higher NINJ2 expression in blood (p = 7.0 × 10^-6), which was confirmed in vitro (p = 0.009). Finally, NINJ2 expression is downregulated by IFNβ treatment and related to TTFR.

CONCLUSIONS

Rs7298096 could influence MS disease activity during IFNβ treatment by modulating NINJ2 expression in blood. The gene encodes for an adhesion molecule involved in inflammation and endothelial cells activation, supporting its role in MS.

Genetic Risk Factors for Ischemic and Hemorrhagic Stroke

Understanding the genetic risk factors for stroke is an essential step to decipher the underlying mechanisms, facilitate the identification of novel therapeutic targets, and optimize the design of prevention strategies. A very small proportion of strokes are attributable to monogenic conditions, the vast majority being multifactorial, with multiple genetic and environmental risk factors of small effect size. Genome-wide association studies and large international consortia have been instrumental in finding genetic risk factors for stroke. While initial studies identified risk loci for specific stroke subtypes, more recent studies also revealed loci associated with all stroke and all ischemic stroke. Risk loci for ischemic stroke and its subtypes have been implicated in atrial fibrillation (PITX2 and ZFHX3), coronary artery disease (ABO, chr9p21, HDAC9, and ALDH2), blood pressure (ALDH2 and HDAC9), pericyte and smooth muscle cell development (FOXF2), coagulation (HABP2), carotid plaque formation (MMP12), and neuro-inflammation (TSPAN2). For hemorrhagic stroke, two loci (APOE and PMF1) have been identified.

Sexually Dimorphic Gene Expression Associated with Growth and Reproduction of Tongue Sole (Cynoglossus semilaevis) Revealed by Brain Transcriptome Analysis

In this study, we performed a comprehensive analysis of the transcriptome of one- and two-year-old male and female brains of Cynoglossus semilaevis by high-throughput Illumina sequencing. A total of 77,066 transcripts, corresponding to 21,475 unigenes, were obtained with a N50 value of 4349 bp. Of these unigenes, 33 genes were found to have significant differential expression and potentially associated with growth, from which 18 genes were down-regulated and 12 genes were up-regulated in two-year-old males, most of these genes had no significant differences in expression among one-year-old males and females and two-year-old females. A similar analysis was conducted to look for genes associated with reproduction; 25 genes were identified, among them, five genes were found to be down regulated and 20 genes up regulated in two-year-old males, again, most of the genes had no significant expression differences among the other three. The performance of up regulated genes in Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis was significantly different between two-year-old males and females. Males had a high gene expression in genetic information processing, while female’s highly expressed genes were mainly enriched on organismal systems. Our work identified a set of sex-biased genes potentially associated with growth and reproduction that might be the candidate factors affecting sexual dimorphism of tongue sole, laying the foundation to understand the complex process of sex determination of this economic valuable species.