Neuro-oncological Ventral Antigen Research Articles

Upregulation of FGF9 and NOVA1 in cancer-associated fibroblasts promotes cell proliferation, invasion and migration of triple negative breast cancer.

Cancer-associated fibroblasts (CAFs) play a pivotal role in cancer progression. This study aimed to explore the roles of CAFs-derived Fibroblast growth factor 9 (FGF9) and Neuro-oncological ventral antigen 1 (NOVA1) in triple negative breast cancer (TNBC) progression. MDA-MB-231 and BT-549 cells were cocultured with CAF conditioned-medium (CAF-CM) or normal fibroblasts conditioned-medium (NF-CM). MTT, EdU, colony formation, wound healing, transwell migration, and invasion assays were employed to determine cell proliferation, migration and invasion, respectively. Western blot and RT-qPCR were carried out to examine the protein and mRNA expression of FGF9 and NOVA1. Xenograft tumor experiments were conducted to evaluate the effects of CAFs, FGF9, and NOVA1 on tumor growth in vivo. Our results showed that CAFs significantly promoted the proliferation, invasion, and migration of TNBC cells. FGF9 and NOVA1 were significantly upregulated in TNBC CAFs, tissues and cells. CAF-CM also could increase the expression of FGF9 and NOVA1 in TNBC cells. Knockdown of FGF9 or NOVA1 could hamper cell proliferation, invasion, migration, and EMT of TNBC cells. Moreover, CAFs with FGF9/NOVA1 knockdown also could inhibit TNBC progression. Besides, CAFs significantly accelerated tumor growth in vivo, which was blocked by FGF9/NOVA1 knockdown in nude mice. In conclusion, our results indicated the tumor-promoting role of CAFs in TNBC progression. FGF9 and NOVA1 upregulation in CAFs induced cell proliferation, migration and invasion in vitro, and facilitated tumor growth in vivo in TNBCdevelopment.

Alternative Splicing Changes Promoted by NOVA2 Upregulation in Endothelial Cells and Relevance for Gastric Cancer.

Angiogenesis is crucial for cancer progression. While several anti-angiogenic drugs are in use for cancer treatment, their clinical benefits are unsatisfactory. Thus, a deeper understanding of the mechanisms sustaining cancer vessel growth is fundamental to identify novel biomarkers and therapeutic targets. Alternative splicing (AS) is an essential modifier of human proteome diversity. Nevertheless, AS contribution to tumor vasculature development is poorly known. The Neuro-Oncological Ventral Antigen 2 (NOVA2) is a critical AS regulator of angiogenesis and vascular development. NOVA2 is upregulated in tumor endothelial cells (ECs) of different cancers, thus representing a potential driver of tumor blood vessel aberrancies. Here, we identified novel AS transcripts generated upon NOVA2 upregulation in ECs, suggesting a pervasive role of NOVA2 in vascular biology. In addition, we report that NOVA2 is also upregulated in ECs of gastric cancer (GC), and its expression correlates with poor overall survival of GC patients. Finally, we found that the AS of the Rap Guanine Nucleotide Exchange Factor 6 (RapGEF6), a newly identified NOVA2 target, is altered in GC patients and associated with NOVA2 expression, tumor angiogenesis, and poor patient outcome. Our findings provide a better understanding of GC biology and suggest that AS might be exploited to identify novel biomarkers and therapeutics for anti-angiogenic GC treatments.

Circ-EIF3I facilitates proliferation, migration, and invasion of lung cancer via regulating the activity of Wnt/β-catenin pathway through the miR-1253/NOVA2 axis.

Many studies have shown that circular RNA (circRNA) is an important regulator mediating the malignant progression of cancer. However, the role and mechanism of circ-EIF3I in lung cancer (LC) development are still unclear. A total 36 paired LC tumor tissues and adjacent normal tissues were enrolled. The expression of circ-EIF3I, microRNA (miR)-1253, and neuro-oncological ventral antigen 2 (NOVA2) was measured by quantitative real-time PCR. The proliferation, apoptosis, migration, and invasion of LC cells were determined by MTT assay, colony formation assay, flow cytometry, and transwell assay. Dual-luciferase reporter assay was performed to verify the interaction between miR-1253 and circ-EIF3I or NOVA2. The protein levels of NOVA2 and Wnt/β-catenin pathway-related markers were detected by western blot analysis. Xenograft tumor was constructed to explore the function of circ-EIF3I on LC tumor growth. Circ-EIF3I was upregulated in LC tumor tissues and cells. Silenced circ-EIF3I could suppress the proliferation, migration, invasion, and enhance the apoptosis of LC cells in vitro, as well as reduce LC tumor growth in vivo. Circ-EIF3I could sponge miR-1253, and miR-1253 inhibitor overturned the regulation of circ-EIF3I knockdown on LC cell progression. NOVA2 was confirmed to be a target of miR-1253, which could reverse the inhibitory effects of miR-1253 on LC cell progression. Further experiments showed that circ-EIF3I regulated NOVA2 expression by sponging miR-1253. In addition, circ-EIF3I silencing could inhibit the activity of Wnt/β-catenin pathway via regulating the miR-1253/NOVA2 axis. Circ-EIF3I might function as an oncogene in LC, which promoted LC progression by the miR-1253/NOVA2/Wnt/β-catenin network.

Neuro-oncological Ventral Antigen 2 Regulates Splicing of Vascular Endothelial Growth Factor Receptor 1 and Is Required for Endothelial Function

Pre-eclampsia (PE) affects 2–8% of pregnancies and is responsible for significant morbidity and mortality. The maternal clinical syndrome (defined by hypertension, proteinuria, and organ dysfunction) is the result of endothelial dysfunction. The endothelial response to increased levels of soluble FMS-like Tyrosine Kinase 1 (sFLT1) is thought to play a central role. sFLT1 is released from multiple tissues and binds VEGF with high affinity and antagonizes VEGF. Expression of soluble variants of sFLT1 is a result of alternative splicing; however, the mechanism is incompletely understood. We hypothesize that neuro-oncological ventral antigen 2 (NOVA2) contributes to this. NOVA2 was inhibited in human umbilical vein endothelial cells (HUVECs) and multiple cellular functions were assessed. NOVA2 and FLT1 expression in the placenta of PE, pregnancy-induced hypertension, and normotensive controls was measured by RT-qPCR. Loss of NOVA2 in HUVECs resulted in significantly increased levels of sFLT1, but did not affect expression of membrane-bound FLT1. NOVA2 protein was shown to directly interact with FLT1 mRNA. Loss of NOVA2 was also accompanied by impaired endothelial functions such as sprouting. We were able to restore sprouting capacity by exogenous VEGF. We did not observe statistically significant regulation of NOVA2 or sFLT1 in the placenta. However, we observed a negative correlation between sFLT1 and NOVA2 expression levels. In conclusion, NOVA2 was found to regulate FLT1 splicing in the endothelium. Loss of NOVA2 resulted in impaired endothelial function, at least partially dependent on VEGF. In PE patients, we observed a negative correlation between NOVA2 and sFLT1.

Landscape of Alternative Splicing Events Related to Prognosis and Immune Infiltration in Glioma: A Data Analysis and Basic Verification.

Background Glioma is a prevalent primary brain cancer with high invasiveness and typical local diffuse infiltration. Alternative splicing (AS), as a pervasive transcriptional regulatory mechanism, amplifies the coding capacity of the genome and promotes the progression of malignancies. This study was aimed at identifying AS events and novel biomarkers associated with survival for glioma. Methods RNA splicing patterns were collected from The Cancer Genome Atlas SpliceSeq database, followed by calculating the percentage of splicing index. Expression profiles and related clinical information of glioma were integrated based on the UCSC Xena database. The AS events in glioma were further analyzed, and glioma prognosis-related splicing factors were identified with the use of bioinformatics analysis and laboratory techniques. Further immune infiltration analysis was performed. Results Altogether, 9028 AS events were discovered. Upon univariate Cox analysis, 425 AS events were found to be related to the survival of patients with glioma, and 42 AS events were further screened to construct the final prognostic model (area under the curve = 0.974). Additionally, decreased expression of the splicing factors including Neuro-Oncological Ventral Antigen 1 (NOVA1), heterogeneous nuclear ribonucleoprotein C (HNRNPC), heterogeneous nuclear ribonucleoprotein L-like protein (HNRNPLL), and RNA-Binding Motif Protein 4 (RBM4) contributed to the poor survival in glioma. The immune infiltration analysis demonstrated that AS events were related to the proportion of immune cells infiltrating in glioma. Conclusions It is of great value for comprehensive consideration of AS events, splicing networks, and related molecular subtype clusters in revealing the underlying mechanism and immune microenvironment remodeling for glioma, which provides clues for the further verification of related therapeutic targets.

MicroRNA miR-27a-3p accelerates cardiac hypertrophy by targeting neuro-oncological ventral antigen 1

ABSTRACT MiRNAs are a class of small non-coding RNAs (ncRNAs) responsible for post-transcriptional regulation of target genes. Accumulating evidence indicates that miRNAs are implicated in the progression of cardiac hypertrophy. Therefore, understanding the molecular mechanisms how these miRNAs regulate cardiac hypertrophy is useful for diagnosis and monitoring of disease progression. In this study, to investigate the effect of miR-27a-3p, we established an in vitro cardiac hypertrophy model by treating H9c2 cardiomyocytes with angiotensin II (Ang II) and an in vivo model through the chronic infusion of Ang II into mice. As revealed by our experimental results, miR-27a-3p expression was significantly increased in clinical samples, animal and cell models of cardiac hypertrophy. Inhibiting miR-27a-3p mitigated cardiac hypertrophy phenotype induced by Ang II. Additionally, our work identified NOVA1 (neuro-oncological ventral antigen 1) as a downstream target of miR-27a-3p. miR-27a-3p overexpression reduced NOVA1 protein level and mRNA expression. Consistently, NOVA1 silencing promoted cardiac hypertrophy phenotype induced by Ang II. In summary, these results suggest that the upregulation of miR-27a-3p may serve as a diagnostic factor for cardiac hypertrophy, and miR-27a-3p upregulation promotes cardiac hypertrophy by targeting NOVA1.

NOVA1 promotes SMN2 exon 7 splicing by binding the UCAC motif and increases SMN protein expression.

Spinal muscular atrophy (SMA) is a rare hereditary neuromuscular disease with a high lethality rate in infants. Variants in the homologous genes survival of motor neuron (SMN)1 and SMN2 have been reported to be SMA pathogenic factors. Previous studies showed that a high inclusion rate of SMN2 exon 7 increased SMN expression, which in turn reduced the severity of SMA. The inclusion rate of SMN2 exon 7 was higher in neural tissues than in non-neural tissues. Neuro-oncological ventral antigen (NOVA) is a splicing factor that is specifically and highly expressed in neurons. It plays a key role in nervous system development and in the induction of nervous system diseases. However, it remains unclear whether this splicing factor affects SMA. In this study, we analyzed the inclusion of SMN2 exon 7 in different tissues in a mouse model of SMA (genotype smn-/-SMN22tg/0) and littermate controls (genotype smn+/-SMN22tg/0). We found that inclusion level of SMN2 exon 7 was high in the brain and spinal cord tissue, and that NOVA1 was also highly expressed in nervous system tissues. In addition, SMN2 exon 7 and NOVA1 were expressed synchronously in the central nervous system. We further investigated the effects of NOVA1 on disease and found that the number of neurons in the anterior horn of spinal cord decreased in the mouse model of SMA during postnatal days 1-7, and that NOVA1 expression levels in motor neurons decreased simultaneously as spinal muscular atrophy developed. We also found that in vitro expression of NOVA1 increased the inclusion of SMN2 exon 7 and expression of the SMN2 protein in the U87MG cell line, whereas the opposite was observed when NOVA1 was knocked down. Finally, point mutation and RNA pull-down showed that the UCAC motif in SMN2 exon 7 plays a critical role in NOVA1 binding and promoting the inclusion of exon 7. Moreover, CA was more essential for the inclusion of exon 7 than the order of Y residues in the motif. Collectively, these findings indicate that NOVA1 interacts with the UCAC motif in exon 7 of SMN2, thereby enhancing inclusion of exon 7 in SMN2, which in turn increases expression of the SMN protein.

Knockdown of NOVA1 inhibits inflammation and migration of asthmatic airway smooth muscle cells to regulate PTEN/Akt pathway by targeting PTBP1

NOVA1 (neuro-oncological ventral antigen 1) is a neuron specific RNA binding protein, belonging to the Nova family, which plays an important role in various diseases. However, the role of NOVA1 in childhood asthma remains unclear. This study was aimed to investigate the role of NOVA1 in TGF-β1-induced ASMCs proliferation and migration as well as the potential mechanisms. In our study, the NOVA1 expression was significantly increased in asthmatic tissues and TGF-β1-induced ASMCs. Inhibition of NOVA1 significantly inhibited TGF-β1-induced ASMCs cell proliferation and migration, and alleviates TGF-β1-induced inflammation. NOVA1 positively regulated the PTBP1 expression and si-NOVA1 inhibited the activation of PTEN/AKT signal pathway. Importantly, the overexpression of PTBP1 partially reversed the effect of NOVA1 on cell viability, migration, inflammation and the activation of PTEN/AKT signal pathway. Generally, our study demonstrated that si-NOVA1 inhibited TGF-β1-induced inflammation and migration in ASMCs through PTBP1/PTEN/AKT pathway. Therefore, inhibition of NOVA1 may be useful for the prevention or treatment of asthma airway remodeling.

Roles of the microRNA‑338‑3p/NOVA1 axis in retinoblastoma.

Retinoblastoma (RB) is an intraocular malignancy that mainly affects young children. Previous reports have demonstrated that mutations or the inactivation of the RB1 gene were the main cause of RB; however, disruption of the intracellular signaling pathways following deficiency of RB1 requires further investigation. Based on the Gene Expression Omnibus data and bioinformatics prediction, the present study aimed to investigate the microRNA (miR)-338-3p/neuro-oncological ventral antigen 1 (NOVA1) axis in RB. Subsequently, overexpression and knockdown of miR-338-3p and NOVA1, respectively, were performed to study the role of miR-338-3p/NOVA1 in the progression of the RB cells. The results demonstrated that overexpression of miR-338-3p significantly inhibited cell proliferation, migration and invasion, and promoted apoptosis of the RB cells. Moreover, knockdown of NOVA1 showed similar results. A dual-luciferase reporter assay and rescue experiments further confirmed the direct binding between miR-338-3p and NOVA1. Taken together, the results indicated that miR-338-3p acted as tumor suppressor by targeting the oncogene of NOVA1 in RB, which may serve as potential therapeutic targets in RB.

Reintroduction of the archaic variant of NOVA1 in cortical organoids alters neurodevelopment.

The evolutionarily conserved splicing regulator neuro-oncological ventral antigen 1 (NOVA1) plays a key role in neural development and function. NOVA1 also includes a protein-coding difference between the modern human genome and Neanderthal and Denisovan genomes. To investigate the functional importance of an amino acid change in humans, we reintroduced the archaic allele into human induced pluripotent cells using genome editing and then followed their neural development through cortical organoids. This modification promoted slower development and higher surface complexity in cortical organoids with the archaic version of NOVA1 Moreover, levels of synaptic markers and synaptic protein coassociations correlated with altered electrophysiological properties in organoids expressing the archaic variant. Our results suggest that the human-specific substitution in NOVA1, which is exclusive to modern humans since divergence from Neanderthals, may have had functional consequences for our species' evolution.

Comprehensive exploratory autoantibody profiling in patients with early rheumatoid arthritis treated with methotrexate or tocilizumab.

BackgroundWe sought to identify immunoglobin G autoantibodies predictive of early treatment response to methotrexate, the recommended first-line therapy for patients with newly diagnosed rheumatoid arthritis, and to the interleukin-6 receptor inhibitor biologic tocilizumab, initiated as the first disease-modifying anti-rheumatic drug.Materials and methodsIn baseline sera of a subset of patients with newly diagnosed rheumatoid arthritis in the U-Act-Early study, selected based on specific responder/non-responder criteria using the Disease Activity Score assessing 28 joints (DAS28) within the first 20 weeks, we measured immunoglobin G antibody reactivity against 463 protein antigens and performed supervised cluster analysis to identify predictive autoantibodies for treatment response. The analysis subset comprised 56 patients in the methotrexate arm (22 responders, 34 non-responders) and 50 patients in the tocilizumab arm (34 responders, 16 non-responders). For comparison, these analyses were also performed in 50 age- and gender-matched healthy controls.ResultsIncreased reactivity in responders versus non-responders was found in the methotrexate arm against two antigens—DOT1-like histone lysine methyltransferase (p = 0.009) and tropomyosin (p = 0.003)—and in the tocilizumab arm against one antigen—neuro-oncological ventral antigen 2 (p = 0.039). Decreased reactivity was detected against two antigens in the methotrexate arm—G1 to S phase transition 2 (p = 0.023) and the zinc finger protein ZPR1 (p = 0.021). Reactivity against the identified antigens was not statistically significant in either treatment arm for patients with rheumatoid factor–positive versus–negative or anti-cyclic citrullinated test–positive versus test–negative rheumatoid arthritis (p ≥ 0.06).ConclusionsComprehensive profiling of baseline sera revealed several novel immunoglobin G autoantibodies associated with early treatment response to methotrexate and to tocilizumab in disease-modifying anti-rheumatic drug-naive patients with rheumatoid arthritis. These findings could eventually yield clinically relevant predictive markers, if corroborated in different patient cohorts, and may facilitate future benefit in personalised healthcare.

Hsa_circ_0046263 Drives the Carcinogenesis and Metastasis of Non-Small Cell Lung Cancer Through the Promotion of NOVA2 by Absorbing Mir-940 as a Molecular Sponge.

BackgroundCircular RNAs (circRNAs) have increasingly been investigated in different cancers due to their regulatory roles. In this study, hsa_circ_0046263 will be detailedly researched in non-small cell lung cancer (NSCLC).MethodsThe analyses of hsa_circ_0046263, microRNA-940 (miR-940), and neuro-oncological ventral antigen 2 (NOVA2) levels were administrated by quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation detection was conducted using Cell Counting Kit-8 (CCK-8) and colony formation assays. Cell cycle and apoptosis were evaluated by flow cytometry. Transwell assay for migration and invasion was used to determine cell metastatic capacity. Overall protein levels were examined adopting Western blot. Target binding analysis was completed via dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. The effect of hsa_circ_0046263 on NSCLC in vivo was studied by xenograft model in mice.ResultsHsa_circ_0046263 was overtly upregulated in NSCLC with important prognostic value. In vitro experiments indicated that hsa_circ_0046263 knockdown caused inhibitory effects on NSCLC cell proliferation, cell cycle, and metastasis but stimulative effect on apoptosis. Molecular mechanism analysis demonstrated that hsa_circ_0046263 served as a miR-940 sponge to act in the development of NSCLC. Moreover, miR-940 targeted NOVA2 and NOVA2 was regulated by hsa_circ_0046263/miR-940 axis. NOVA2 overexpression also neutralized the miR-940-mediated progression inhibition of NSCLC cells. In vivo assays suggested that hsa_circ_0046263 enhanced NSCLC tumorigenesis by targeting miR-940/NOVA2 axis.ConclusionHsa_circ_0046263 was identified as a cancer-promoting factor in NSCLC via sponging miR-940 and upregulating NOVA2, which presented a clear mechanism of NSCLC occurrence and progression.

MiR-582-5p inhibits the growth and invasion of osteosarcoma cell by targeting NOVA1.

To investigate the role of microRNA-582-5p (miR-582-5p) on osteosarcoma (OS) cell behaviors and provide potential therapeutic targets for OS. Expression levels of miR-582-5p in OS cell lines and normal cell lines were measured by quantitative real-time PCR. Cell proliferation, migration and invasion capacities were assessed by cell counting kit-8 assay, wound-healing assay, and transwell invasion assay, respectively. Downstream target of miR-582-5p was confirmed by Luciferase activity reporter assay and Western blotting assay. MiR-582-5p expression was downregulated in OS cell lines compared with normal cell lines. Overexpression of miR-582-5p inhibits OS cell proliferation, migration, and invasion capacities. Neuro-oncological ventral antigen 1 (NOVA1) was chosen as target gene of miR-582-5p by bioinformatics analysis and Luciferase reporter assay. Moreover, overexpression of NOVA1 could impair tumor suppression role of miR-582-5p on OS cell behaviors. MiR-582-5p exerts tumor-suppressive role on OS cell behaviors via targeting NOVA1 in vitro, which will help us to understand the mechanisms underlying OS progression.

Circ_0000376, a Novel circRNA, Promotes the Progression of Non-Small Cell Lung Cancer Through Regulating the miR-1182/NOVA2 Network.

BackgroundHypoxia has been shown to induce the malignant progression of cancer, including non-small cell lung cancer (NSCLC). Circular RNA (circRNA) is considered to be an important regulator of cancer progression. However, the role of a newly discovered circRNA, circ_0000376, in the progression of NSCLC is unclear.MethodsThe relative expression levels of circ_0000376, miR-1182 and neuro-oncological ventral antigen 2 (NOVA2) were detected via quantitative real-time polymerase chain reaction (qRT-PCR). Glucose consumption and lactate production were determined using Glucose Assay Kit and Lactate Assay Kit, respectively. Moreover, the protein levels of glycolysis markers and NOVA2 were measured using Western blot (WB) analysis. Furthermore, 3-(4, 5-dimethyl-2 thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay was performed to assess cell viability, and transwell assay was employed to evaluate cell migration and invasion. The interaction between miR-1182 and circ_0000376 or NOVA2 was confirmed by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. In addition, animal experiments were conducted to assess the influence of circ_0000376 silencing on NSCLC tumor growth in vivo.ResultsCirc_0000376 was upregulated in NSCLC, and its high expression was related to the poor overall survival of NSCLC patients. Hypoxia could enhance circ_0000376 expression and promote the glycolysis, viability, migration, and invasion of NSCLC cells. However, silencing of circ_0000376 could inhibit the glycolysis, viability, migration, and invasion of hypoxia-induced NSCLC cells. Additionally, circ_0000376 could sponge miR-1182, and miR-1182 could target NOVA2. MiR-1182 silencing could reverse the inhibitory effect of circ_0000376 knockdown on NSCLC progression, and NOVA2 overexpression also could reverse the suppressive effect of miR-1182 overexpression on NSCLC progression. Meanwhile, miR-1182 inhibitor could invert the negative regulation effect of circ_0000376 silencing on NOVA2 expression. In addition, circ_0000376 knockdown inhibited the NSCLC tumor growth via regulating the miR-1182 and NOVA2 expression in vivo.ConclusionCirc_0000376 promoted NSCLC progression by regulating the miR-1182/NOVA2 axis, suggesting that circ_0000376 might be a potential biomarker for NSCLC treatment.

NOVA1 expression is associated with clinicopathological characteristics and prognosis in patients with small cell lung cancer.

BackgroundSmall cell lung cancer (SCLC) is a highly aggressive lung malignancy which is characteristic of rapid tumor proliferation, metastasis as well as paraneoplastic neurological syndromes (PNS). Recent studies have shown that neuro-oncological ventral antigen-1 (NOVA1) plays a crucial role in the progression of various tumors. However, its effect on SCLC is still exclusive. This study was aimed to explore NOVA1 expression in tumor tissues of SCLC patients as well as its correlation with clinicopathological characteristics and cancer-specific overall survivals.MethodsIn this study, the patients pathologically diagnosed with new primary SCLC were enrolled. Firstly, we compared NOVA1 expression in SCLC tissues and adjacent normal tissues by immunohistochemistry. We further investigated the association of NOVA1 expression with clinicopathological markers (especially the categories of PNS) and survival time in SCLC patients.ResultsOur finding exhibited that NOVA1 was remarkably expressed in SCLC tumorous tissues compared with adjacent normal lung tissues (P<0.001). Additionally, NOVA1 expression was closely associated with clinicopathological characteristics in SCLC patients in terms of tumor staging(χ2=15.833; P<0.001), lymph node metastasis (χ2=9.624; P=0.002), brain metastasis (χ2=9.624; P=0.002) and PNS (χ2=5.004; P=0.024). With the COX proportional hazard regression model, we detected that high expression of NOVA1 (HR =0.445; 95% CI: 0.213–0.934; P=0.032) was an independent factor for shorter survival time.ConclusionsHigh expression of NOVA1 is closely associated with aggressive clinicopathological characteristics including PNS as well as poor survival in SCLC patients. NOVA1 can be served as a promising predictive factor for prognosis in SCLC.

MiR-27-3p inhibition restore fibroblasts viability in diabetic wound by targeting NOVA1.

Diabetic wounds increase morbidity and decrease quality of life in patients with type 2 diabetes. Serum miR-27-3p levels are reportedly elevated in type 2 diabetic patients. In the present study, we explored the role of miR-27-3p during wound healing. We found that miR-27-3p is overexpressed in cutaneous fibroblasts of diabetic patients and mice. miR-27-3p knockdown enhanced the proliferation and migration of fibroblasts, while suppressing the incidence of fibroblast apoptosis. Overexpressing miR-27-3p in fibroblasts had the opposite effects. We also identified neuro-oncological ventral antigen 1 (NOVA1) as a target of miR-27-3p in fibroblasts. Knocking down NOVA1 using targeted siRNA mimicked the effects of miR-27-3p overexpression in fibroblasts. Administration of miR-27-3p to the area around wounds inflicted in mice delayed healing of those wounds. This suggests that miR-27-3p suppresses fibroblast function by targeting NOVA1, which results in the slowing of wound healing. These findings may offer a new approach to the treatment of diabetic wound healing.

Sevoflurane inhibits neuronal migration and axon growth in the developing mouse cerebral cortex.

The highly organized laminar structure of the mammalian brain is dependent on successful neuronal migration, and migration deficits can cause lissencephaly and behavioral and cognitive defects. Here, we investigated the contribution of neuronal migration dysregulation to anesthesia-induced neurotoxicity in the fetal brain. Pregnant C57BL/6 mice at embryonic day 14.5 received 2.5% sevoflurane daily for two days. Cortical neuron migration and axon lengths were evaluated using GFP immunostaining. Morris water maze tests were performed to assess the effects of sevoflurane exposure on spatial memory in offspring. We found that sevoflurane exposure decreased axon length and caused cognitive defects in young mice. RNA sequencing revealed that these defects were associated with reduced neuro-oncological ventral antigen 2 (Nova2) expression. In utero electroporation experiments using Nova2 shRNA recapitulated this finding. Nova2 shRNA inhibited neuronal migration and decreased axon lengths. Finally, we found that Netrin-1/Deleted in Colorectal Cancer (Dcc) proteins acted downstream of Nova2 to suppresses neuronal migration. These findings describe a novel mechanism by which prenatal anesthesia exposure affects embryonic neural development and postnatal behavior.

De Novo Frameshift Variants in the Neuronal Splicing Factor NOVA2 Result in a Common C-Terminal Extension and Cause a Severe Form of Neurodevelopmental Disorder

The neuro-oncological ventral antigen 2 (NOVA2) protein is a major factor regulating neuron-specific alternative splicing (AS), previously associated with an acquired neurologic condition, the paraneoplastic opsoclonus-myoclonus ataxia (POMA). We report here six individuals with de novo frameshift variants in NOVA2 affected with a severe neurodevelopmental disorder characterized by intellectual disability (ID), motor and speech delay, autistic features, hypotonia, feeding difficulties, spasticity or ataxic gait, and abnormal brain MRI. The six variants lead to the same reading frame, adding a common proline rich C-terminal part instead of the last KH RNA binding domain. We detected 41 genes differentially spliced after NOVA2 downregulation in human neural cells. The NOVA2 variant protein shows decreased ability to bind target RNA sequences and to regulate target AS events. It also fails to complement the effect on neurite outgrowth induced by NOVA2 downregulation invitro and to rescue alterations of retinotectal axonal pathfinding induced by loss of NOVA2 ortholog in zebrafish. Our results suggest a partial loss-of-function mechanism rather than a full heterozygous loss-of-function, although a specific contribution of the novel C-terminal extension cannot be excluded.

Identification of NOVA family proteins as novel β-catenin RNA-binding proteins that promote epithelial-mesenchymal transition

ABSTRACT The NOVA (neuro-oncological ventral antigen) protein family, composed of two paralogs, NOVA1 and NOVA2, consists of RNA-binding proteins involving in processes such as alternative splicing and transport of some target mRNAs. The function of NOVA has been well studied, and increasing evidence has shown that NOVA proteins may be important contributors to carcinogenesis. However, the molecular mechanisms underlying the roles of NOVA proteins in carcinogenesis remain to be determined. Here, we have identified both NOVA1 and NOVA2 as novel β-catenin RNA-binding proteins. The NOVA1/NOVA2 heterodimer positively regulates β-catenin expression by enhancing β-catenin mRNA stability. Furthermore, we demonstrated that NOVA1 and NOVA2 promote epithelial-mesenchymal transition via β-catenin in breast cancer cells, as NOVA-induced upregulation of epithelial and mesenchymal marker expression was attenuated by restoring β-catenin expression. Our results advance the current understanding of β-catenin post-transcriptional regulation and shed light on the role of NOVA proteins in cancer, suggesting that NOVA proteins are potential therapeutic targets in breast cancer.

Expression of neuro-oncological ventral antigen-1 in small-cell lung cancer and its value in pathological diagnosis.

BackgroundTo investigate the expression of neuro-oncological ventral antigen-1 (Nova1) in small-cell lung cancer (SCLC) and its value in clinical pathological diagnosis of SCLCs.MethodsNova1 expression in the SCLC cell line H446, lung adenocarcinoma cell line A549, squamous cell carcinoma (SCC) cell line H226 and bronchial epithelial cell line BEAS-2B were examined by RT-PCR. It’s expression in paraffin specimens of 100 SCLC cases, 15 specimens of lung adenocarcinoma cases and 15 specimens of lung SCC cases, as well as adjacent normal tissue was determined by immunohistochemistry. The positive rate of Nova1 in SCLC tissue was compared with those of traditional neuroendocrine markers CD56, Syn and CgA.ResultsNova1 expression in SCLC cell line H446 was significantly higher than that of bronchial epithelial cell line BEAS-2B and lung adenocarcinoma cell line A549 and SCC cell line H226. The positive rate of Nova1 in SCLC tissue was similar to that of CD56 but higher than those of Syn and CgA. Nova1 was neither expressed in the cancer tissue nor in the adjacent normal tissue of the 15 cases of SCC and the 15 cases of adenocarcinoma. In all six cases of combined SCLC, Nova1 was expressed in the SCLC component, whereas markers of SCC or adenocarcinoma were absent.ConclusionsNova1 can be used as a novel neuroendocrine marker for pathological diagnosis of SCLC in clinical practice with high sensitivity and specificity, in addition to its role as an independent prognostic marker of overall survival and tumour recurrence, as suggested by previous studies.