Search

In order to investigate the correlation between neuroaxon-guiding factor (Netrin-1), deleted in colorectal cancer (DCC), uncoordinated 5B (UNC5B), and vascular endothelial growth factor (VEGF) expression machine in villus tissues of delayed abortion in colorectal cancer, a total of 120 pregnant women are selected from February 2019 to August 2021. The two groups of subjects improve the relevant examinations before surgery and the underwent negative pressure induces abortion hysterectomy guided by abdominal ultrasound under intravenous anesthesia. The mRNA and protein expressions of netrin-1, DCC, UNC5B, and VEGF in the villi of the two groups are detected by real-time fluorescence quantitative polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC), and the correlation of the four indicators is analyzed by Pearson's test.

Anterolateral system (AS) neurons transmit pain signals from the spinal cord to the brain. Their morphology, anatomy, and physiological properties have been extensively characterized and suggest that specific AS neurons and their brain targets are concerned with the discriminatory aspects of noxious stimuli, such as their location or intensity, and their motivational/emotive dimension. Among the recently unraveled molecular markers of AS neurons is the developmentally expressed transcription factor Phox2a, providing us with the opportunity to selectively disrupt the embryonic wiring of AS neurons to gain insights into the logic of their adult function. As mice with a spinal-cord-specific loss of the netrin-1 receptor deleted in colorectal carcinoma (DCC) have increased AS neuron innervation of ipsilateral brain targets and defective noxious stimulus localization or topognosis, we generated mice of either sex carrying a deletion ofDccin Phox2a neurons. SuchDccPhox2amice displayed impaired topognosis along the rostrocaudal axis but with little effect on left-right discrimination and normal aversive responses. Anatomical tracing experiments inDccPhox2amice revealed defective targeting of cervical and lumbar AS axons within the thalamus. Furthermore, genetic labeling of AS axons revealed their expression of DCC on their arrival in the brain, at a time when many of their target neurons are being born and expressNtn1. Our experiments suggest a postcommissural crossing function for netrin-1:DCC signaling during the formation of somatotopically ordered maps and are consistent with a discriminatory function of some of the Phox2a AS neurons.SIGNIFICANCE STATEMENTHow nociceptive (pain) signals are relayed from the body to the brain remains an important question relevant to our understanding of the basic physiology of pain perception. Previous studies have demonstrated that the AS is a main effector of this function. It is composed of AS neurons located in the spinal cord that receive signals from nociceptive sensory neurons that detect noxious stimuli. In this study, we generate a genetic miswiring of mouse AS neurons that results in a decreased ability to perceive the location of a painful stimulus. The precise nature of this defect sheds light on the function of different kinds of AS neurons and how pain information may be organized.

Background: Congenital mirror movements are involuntary movements of a side of the body imitating intentional movements on the opposite side, appearing in early childhood and persisting beyond 7 years of age. Congenital mirror movements are usually idiopathic but have been reported in association with various brain malformations. Methods: We describe clinical, genetic, and radiologic features in 9 individuals from 5 families manifesting congenital mirror movements. Results: The brain malformations associated with congenital mirror movements were: dysplastic corpus callosum in father and daughter with a heterozygous p.Met1* mutation in DCC; hypoplastic corpus callosum, dysgyria, and malformed vermis in a mother and son with a heterozygous p.Thr312Met mutation in TUBB3; dysplastic corpus callosum, dysgyria, abnormal vermis, and asymmetric ventricles in a father and 2 daughters with a heterozygous p.Arg121Trp mutation in TUBB; hypoplastic corpus callosum, dysgyria, malformed basal ganglia and abnormal vermis in a patient with a heterozygous p.Glu155Asp mutation in TUBA1A; hydrocephalus, hypoplastic corpus callosum, polymicrogyria, and cerebellar cysts in a patient with a homozygous p.Pro312Leu mutation in POMGNT1. Conclusion: DCC, TUBB3, TUBB, TUBA1A, POMGNT1 cause abnormal axonal guidance via different mechanisms and result in congenital mirror movements associated with brain malformations.

Background Genetic variation in the guidance cue DCC gene is linked to psychopathologies involving dysfunction in the prefrontal cortex. We created an expression-based polygenic risk score (ePRS) based on the DCC coexpression gene network in the prefrontal cortex, hypothesizing that it would be associated with individual differences in total brain volume. Methods We filtered single nucleotide polymorphisms (SNPs) from genes coexpressed with DCC in the prefrontal cortex obtained from an adult postmortem donors database (BrainEAC) for genes enriched in children 1.5 to 11 years old (BrainSpan). The SNPs were weighted by their effect size in predicting gene expression in the prefrontal cortex, multiplied by their allele number based on an individual’s genotype data, and then summarized into an ePRS. We evaluated associations between the DCC ePRS and total brain volume in children in 2 community-based cohorts: the Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) and University of California, Irvine (UCI) projects. For comparison, we calculated a conventional PRS based on a genome-wide association study of total brain volume. Results Higher ePRS was associated with higher total brain volume in children 8 to 10 years old (β = 0.212, p = 0.043; n = 88). The conventional PRS at several different thresholds did not predict total brain volume in this cohort. A replication analysis in an independent cohort of newborns from the UCI study showed an association between the ePRS and newborn total brain volume (β = 0.101, p = 0.048; n = 80). The genes included in the ePRS demonstrated high levels of coexpression throughout the lifespan and are primarily involved in regulating cellular function. Limitations The relatively small sample size and age differences between the main and replication cohorts were limitations. Conclusion Our findings suggest that the DCC coexpression network in the prefrontal cortex is critically involved in whole brain development during the first decade of life. Genes comprising the ePRS are involved in gene translation control and cell adhesion, and their expression in the prefrontal cortex at different stages of life provides a snapshot of their dynamic recruitment.

Frazzled (Fra) and deleted in colorectal cancer (Dcc) are homologous receptors that promote axon attraction in response to netrin. In Drosophila, Fra also acts independently of netrin by releasing an intracellular domain (ICD) that activates gene transcription. How neurons coordinate these pathways to make accurate guidance decisions is unclear. Here we show that the ADAM metalloprotease Tace cleaves Fra, and this instructs the switch between the two pathways. Genetic manipulations that either increase or decrease Tace levels disrupt midline crossing of commissural axons. These conflicting phenotypes reflect Tace's function as a bi-directional regulator of axon guidance, a function conserved in its vertebrate homolog ADAM17: while Tace induces the formation of the Fra ICD to activate transcription, excessive Tace cleavage of Fra and Dcc suppresses the response to netrin. We propose that Tace and ADAM17 are key regulators of midline axon guidance by establishing the balance between netrin-dependent and netrin-independent signaling.

Traumatic brain injury (TBI) is a common neurological disease. Netrin-1 and deleted in colorectal cancer (DCC) receptor are potential biomarkers associated with nerve regeneration and immune regulation. We aimed to investigate the ability of the DCC receptor and Netrin-1 to predict a high ICP level after operation in severe traumatic brain injury and their prognostic significance. This study is a prospective observational study. We selected 23 patients with traumatic brain injury who had undergone surgical operations as subjects. Immunohistochemical staining was performed on the contusion tissue that was removed by the operation to determine the expression of DCC receptor. At the same time, enzyme-linked immunosorbent assay (ELISA) kits were used to detect the serum Netrin-1 content. Determination of intracranial pressure (ICP) value was measured by intraventricular catheter. The Glasgow Outcome Scale (GOS) score at six months after trauma was defined as the main study endpoint. The results showed that serum Netrin-1 concentrations of patients in the critical TBI group (GCS 3–5 points) was significantly lower than that in the severe TBI group (GCS 6–8 points). The ICP peak and average mannitol consumption in the high Netrin-1 group were significantly lower than those in the low Netrin-1 group. DCC receptor-positive patients had a significantly lower ICP peak. There was no significant difference in six month-GOS scores between patients in the high and low Netrin-1 groups, while DCC receptor concentrations below 3.82 ng/mL predicted poor prognosis (GOS 1–3 points). In conclusion, the expression level of the DCC receptor can better evaluate the postoperative high ICP level and prognosis than the level of serum Netrin-1 in severe traumatic brain injury.

Symptoms of subthreshold depression may differentially affect the illness transition. We examined the impact of cognitive-affective and somatic symptoms on different subthreshold depression transitions as well as risk factors influencing the aforementioned symptoms changes.Adults with subthreshold depression in the Depression Cohort in China were enrolled. Data collection was conducted at baseline, 6 and 12 months from 2019 to 2020. Cognitive-affective and somatic symptoms were assessed using the Patient Health Questionnaire-9. A total of 993 participants completed 12-month follow-up and were divided into persistent, intermittent and remission groups according to change in depressive symptoms. The longitudinal change of cognitive-affective and somatic symptoms in the three groups, as well as risk factors was analyzed using the generalized linear mixed-model.There were 24.07 %, 34.04 % and 41.89 % of participants proceeding into persistent, intermittent and remission subthreshold depression groups, respectively. Cognitive-affective symptoms were the core symptoms for predicting the deterioration in persistent subthreshold depression (t = 2.48, P = 0.013), whereas somatic symptoms improved over time (t = -2.82, P = 0.005). Anxiety symptoms were the primary risk factors for worsening cognitive-affective symptoms (P 0.001), following by insomnia symptoms, age, marital status, resilience and social functions. Somatic symptoms were affected by insomnia symptoms, anxiety symptoms and Body Mass Index successively.Major Depressive Episode was not explored in follow-up.Cognitive-affective symptoms in subthreshold depression are at greater risk of illness deterioration. Future studies should endeavor to identify specific risk factors in different symptoms to forestall the transition from subthreshold to Major Depressive Disorder.

Anterolateral system neurons in lamina I of the spinal cord rely on DCC for the formation of topographically appropriate nociceptive inputs to the brain., Anterolateral system (AS) neurons relay nociceptive information from the spinal cord to the brain, protecting the body from harm by evoking a variety of behaviours and autonomic responses. The developmental programs that guide the connectivity of AS neurons remain poorly understood. Spinofugal axons cross the spinal midline in response to Netrin-1 signalling through its receptor deleted in colorectal carcinoma (DCC); however, the relevance of this canonical pathway to AS neuron development has only been demonstrated recently. Here, we disrupted Netrin-1:DCC signalling developmentally in AS neurons and assessed the consequences on the path finding of the different classes of spinofugal neurons. Many lamina I AS neurons normally innervate the lateral parabrachial nucleus and periaqueductal gray on the contralateral side. The loss of DCC in the developing spinal cord resulted in increased frequency of ipsilateral projection of spinoparabrachial and spinoperiaqueductal gray neurons. Given that contralateral spinofugal projections are largely associated with somatotopic representation of the body, changes in the laterality of AS spinofugal projections may contribute to reduced precision in pain localization observed in mice and humans carrying Dcc mutations.

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.

Genome-wide association studies (GWAS) of major depression and its relevant biological phenotypes have been extensively conducted in large samples, and transcriptome-wide analyses in the tissues of brain regions relevant to pathogenesis of depression, e.g., dorsolateral prefrontal cortex (DLPFC), have also been widely performed recently. Integrating these multi-omics data will enable unveiling of depression risk genes and even underlying pathological mechanisms. Here, we employ summary data-based Mendelian randomization (SMR) and integrative risk gene selector (iRIGS) approaches to integrate multi-omics data from GWAS, DLPFC expression quantitative trait loci (eQTL) analyses and enhancer-promoter physical link studies to prioritize high-confidence risk genes for depression, followed by independent replications across distinct populations. These integrative analyses identify multiple high-confidence depression risk genes, and numerous lines of evidence supporting pivotal roles of the netrin 1 receptor (DCC) gene in this illness across different populations. Our subsequent explorative analyses further suggest that DCC significantly predicts neuroticism, well-being spectrum, cognitive function and putamen structure in general populations. Gene expression correlation and pathway analyses in DLPFC further show that DCC potentially participates in the biological processes and pathways underlying synaptic plasticity, axon guidance, circadian entrainment, as well as learning and long-term potentiation. These results are in agreement with the recent findings of this gene in neurodevelopment and psychiatric disorders, and we thus further confirm that DCC is an important susceptibility gene for depression, and might be a potential target for new antidepressants.

Netrin is a prototypical axon guidance cue. Structural studies have revealed how netrin interacts with the deleted in colorectal cancer (DCC) receptor, other receptors, and co-factors for signaling. Recently, genetic studies suggested that netrin is involved in neuronal haptotaxis, which requires a reversible adhesion process. Structural data indicate that netrin can also mediate trans-adhesion between apposing cells decorated with its receptors on the condition that the auxiliary guidance cue draxin is present. Here, we propose that netrin is involved in conditional adhesion, a reversible and localized process that can contribute to cell adhesion and migration. We suggest that netrin-mediated adhesion and signaling are linked, and that local environmental factors in the ventricular zone, the floor plate, or other tissues coordinate its function.

The outbreak of the COVID-19 epidemic intensified the volatility of commodity markets (the energy and precious metals markets), which created a significant negative impact on the volatility spillovers among these markets. It may also have triggered a new volatility risk contagion. In this paper, we introduce the DCC-GARCH-CONNECTEDNESS approach to explore the volatility spillover level and multi-level spillover structure characteristics among the commodity markets before and during the COVID-19 epidemic in order to clarify the new volatility risk contagion patterns across the markets. The results implied several conclusions. (i) The COVID-19 epidemic has significantly improved the total volatility spillover level of the energy and precious metals markets and has enhanced the risk connectivity among the markets. (ii) The COVID-19 epidemic has amplified the volatility of the crude oil market, making it the main volatility spillover market, namely the source of volatility risk contagion. (iii) The COVID-19 epidemic outbreak enhanced the external risk absorption capacity of the natural gas and silver markets, and the absorption level of the external volatility spillover improved significantly. Furthermore, the risk absorption capacity of the gold market weakened, while the gold market has remained the endpoint of external volatility risk during the epidemic and has acted as a risk stabilizer. (iv) The volatility spillover among markets has clear time-varying characteristics and a positive connectedness with the severity of the COVID-19 epidemic. As the severity of the COVID-19 epidemic increases, the volatility risk connectivity among the markets rapidly increases.

Triple-negative breast cancer (TNBC), an aggressive histological subtype of breast cancer, exhibits a high risk of early recurrence rate and a poor prognosis, and it is primarily associated with the abundance of cancer stem cells (CSCs). At present, the strategies for effectively eradicating or inhibiting TNBC CSCs are still limited, which makes the development of novel drugs with anti-CSCs function be of great value for the treatment of TNBC, especially the refractory TNBC. In this study, we found that the small-molecule tyrosine kinase inhibitor DCC-2036 suppressed TNBC stem cells by inhibiting the tyrosine kinase AXL and the transcription factor KLF5. DCC-2036 downregulated the expression of KLF5 by decreasing the protein stability of KLF5 via the AXL-Akt-GSK3β signal axis, and in turn, the downregulation of KLF5 further reduced the expression of AXL via binding to its promotor (−171 to −162 bp). In addition, p-AXL/AXL levels were positively correlated with KLF5 expression in human TNBC specimens. These findings indicated that DCC-2036 is able to suppress the CSCs in TNBC by targeting the AXL-KLF5 positive feedback loop. Moreover, our findings indicated that DCC-2036 increased the sensitivity of TNBC chemotherapy. Therefore, this study proposes a potential drug candidate and several targets for the treatment of refractory TNBC.

The β-site Amyloid precursor protein Cleaving Enzyme 1 (BACE1) is an extensively studied therapeutic target for Alzheimer’s disease (AD), owing to its role in the production of neurotoxic amyloid beta (Aβ) peptides. However, despite numerous BACE1 inhibitors entering clinical trials, none have successfully improved AD pathogenesis, despite effectively lowering Aβ concentrations. This can, in part, be attributed to an incomplete understanding of BACE1, including its physiological functions and substrate specificity. We propose that BACE1 has additional important physiological functions, mediated through substrates still to be identified. Thus, to address this, we computationally analysed a list of 533 BACE1 dependent proteins, identified from the literature, for potential BACE1 substrates, and compared them against proteins differentially expressed in AD. We identified 15 novel BACE1 substrates that were specifically altered in AD. To confirm our analysis, we validated Protein tyrosine phosphatase receptor type D (PTPRD) and Netrin receptor DCC (DCC) using Western blotting. These findings shed light on the BACE1 inhibitor failings and could enable the design of substrate-specific inhibitors to target alternative BACE1 substrates. Furthermore, it gives us a greater understanding of the roles of BACE1 and its dysfunction in AD.

Mechanisms that determine the survival of midbrain dopaminergic (mDA) neurons in the adult central nervous system (CNS) are not fully understood. Netrins are a family of secreted proteins that are essential for normal neural development. In the mature CNS, mDA neurons express particularly high levels of netrin-1 and its receptor Deleted in Colorectal Cancer (DCC). Recent findings indicate that overexpressing netrin-1 protects mDA neurons in animal models of Parkinson's disease (PD), with a proposed pro-apoptotic dependence function for DCC that triggers cell death in the absence of a ligand. Here, we sought to determine if DCC expression influences mDA neuron survival in young adult and ageing mice. To circumvent the perinatal lethality of DCC null mice, we selectively deleted DCC from mDA neurons utilizing DAT

Schizophrenia (SZ) is a complex disorder caused by a variety of genetic and environmental factors. Mounting evidence suggests the involvement of microRNAs (miRNAs) in the pathology of SZ. Accordingly, the current study set out to investigate the possible implication of the miR-182/183 cluster, as well as its associated mechanism in the progression of SZ. Firstly, rat models of SZ were established by intraperitoneal injection of MK-801. Moreover, rat primary hippocampal neurons were exposed to MK-801 to simulate injury of hippocampal neurons. The expression of miR-182/183 or its putative target gene DCC was manipulated to examine their effects on SZ in vitro and in vivo. It was found that miR-182 and miR-183 were both highly expressed in peripheral blood of SZ patients and hippocampal tissues of SZ rats. In addition, the miR-182/183 cluster could target DDC and downregulate the expression of DDC. On the other hand, inhibition of the miR-182/183 cluster ameliorated SZ, as evidenced by elevated serum levels of NGF and BDNF, along with reductions in spontaneous activity, serum GFAP levels, and hippocampal neuronal apoptosis. Additionally, DCC was found to activate the axon guiding pathway and influence synaptic activity in hippocampal neurons. Collectively, our findings highlighted that inhibition of the miR-182/183 cluster could potentially attenuate SZ through DCC-dependent activation of the axon guidance pathway. Furthermore, inhibition of the miR-182/183 cluster may represent a potential target for the SZ treatment.

Deleted in colorectal cancer (DCC) encodes a transmembrane dependence receptor and is frequently mutated in melanoma. The associations of DCC mutation with chromosomal instability and immunotherapeutic efficacy in melanoma are largely uncharacterised.We performed an integrated study based on biological experiments and multi-dimensional data types, including genomic, transcriptomic and clinical immune checkpoint blockade (ICB)-treated melanoma cohorts from public databases.DCC mutation was significantly correlated with the tumour mutational burden (TMB) in The Cancer Genome Atlas (TCGA), International Cancer Genome Consortium (ICGC) and ICB-treated melanoma cohorts. DCC expression levels were correlated with DNA damage response and repair (DDR) pathways responsive to irradiation (IR) in the Malme-3M and SK-MEL-2 cell lines. In the TCGA cohort, DCC-mutated samples presented more neoantigens, higher proportions of infiltrating antitumour immunocytes and lower proportions of infiltrating pro-tumour immunocytes than DCC wild-type samples. DCC-mutated samples were significantly enriched in activated immune response and DDR pathways. Furthermore, patients harbouring mutated DCC treated with ICB showed remarkable clinical benefits in terms of the response rate and overall survival.Somatic mutations in DCC are associated with improved clinical outcomes in ICB-treated melanoma patients. Once further validated, the DCC mutational status can improve patient selection for clinical practice and future study enrolment.

Based on knowledge of kinase switch-control inhibition and using a combination of structure-based drug design and standard medicinal chemistry principles, we identified a novel series of dihydropyrimidone-based CSF1R kinase inhibitors displaying exquisite selectivity for CSF1R versus a large panel of kinases and non-kinase protein targets. Starting with lead compound 3, an SAR optimization campaign led to the discovery of vimseltinib (DCC-3014; compound 20) currently undergoing clinical evaluation for the treatment of Tenosynovial Giant Cell Tumor (TGCT), a locally aggressive benign tumor associated with substantial morbidity. 2021 Elsevier ltd. All rights reserved.

Deleted in colorectal cancer (DCC) and uncoordinated-5 (UNC5) receptors, play a key role in tumor progression of several solid tumors by inducing apoptosis when unbound to their ligand netrin-1. Netrin 1 is currently being evaluated as a therapeutic target. These receptors, known as dependence receptors, and their ligands, have not yet been extensively explored in hematological malignancies. Here, we performed a screening of various human myeloma cell lines and bone marrow samples from multiple myeloma patients for netrin-1 and its receptors to determine the expression of netrin 1 and its receptors in multiple myeloma as well as to assess the potential anti-myeloma activity of a novel anti-netrin-1 treatment (NP137). Our results showed heterogeneous expression of netrin-1 and its receptors DCC and UNC5H2(B) in six human myeloma lines. Additionally, immunohistochemistry and flow cytometry showed expression of these molecules in a majority of myeloma patient samples. In vitro NP137 did not induce apoptosis of myeloma cell lines yet enhanced the cytotoxicity of bortezomib and dexamethasone. In vivo, NP137 treatment of SCID mice with established RPMI8226 myeloma tumors led to a reduction of tumor size compared to controls. Ex vivo, NP137 lowered the plasma cells percentage in bone marrow aspirates in a fraction of the patient samples analyzed. These results suggest that netrin signaling could constitute a novel therapeutic target in multiple myeloma.

Inhibitory control deficits are prevalent in multiple neuropsychiatric conditions. The communication- as well as the connectivity- between corticolimbic regions of the brain are fundamental for eliciting inhibitory control behaviors, but early markers of vulnerability to this behavioral trait are yet to be discovered. The gradual maturation of the prefrontal cortex (PFC), in particular of the mesocortical dopamine innervation, mirrors the protracted development of inhibitory control; both are present early in life, but reach full maturation by early adulthood. Evidence suggests the involvement of the Netrin-1/DCC signaling pathway and its associated gene networks in corticolimbic development. Here we investigated whether an expression-based polygenic score (ePRS) based on corticolimbic-specific DCC gene co-expression networks associates with impulsivity-related phenotypes in community samples of children. We found that lower ePRS scores associate with higher measurements of impulsive choice in 6-year-old children tested in the Information Sampling Task and with impulsive action in 6- and 10-year-old children tested in the Stop Signal Task. We also found the ePRS to be a better overall predictor of impulsivity when compared to a conventional PRS score comparable in size to the ePRS (4515 SNPs in our discovery cohort) and derived from the latest GWAS for ADHD. We propose that the corticolimbic DCC-ePRS can serve as a novel type of marker for impulsivity-related phenotypes in children. By adopting a systems biology approach based on gene co-expression networks and genotype-gene expression (rather than genotype-disease) associations, these results further validate our methodology to construct polygenic scores linked to the overall biological function of tissue-specific gene networks.

Deleted in colorectal carcinoma (DCC) A > G (rs714) is the most widely studied SNP of tumor suppressor DCC gene found to be associated with increased risk of various cancers. Therefore, the aim of ...

Agenesis of the corpus callosum (ACC) is a common prenatally-detected brain anomaly. Recently, an association between mutations in the DCC Netrin 1 receptor (DCC) gene and ACC, with or without mirror movements, has been demonstrated. In this manuscript, we present a family with a novel heterozygous frameshift mutation in DCC, review the available literature, and discuss the challenges involved in the genetic counseling for recently discovered disorders with paucity of medical information. We performed whole exome sequencing in a healthy nonconsanguineous couple that underwent two pregnancy terminations due to prenatal diagnosis of ACC. A heterozygous variant c.2774dupA (p.Asn925Lysfs*17) in the DCC gene was demonstrated in fetal and paternal DNA samples, as well as in a healthy 4-year-old offspring. When directly questioned, both father and child reported having mirror movements not affecting quality of life. Segregation analysis demonstrated the variant in three paternal siblings, two of them having mirror movements. Brain imaging revealed normal corpus callosum. Summary of literature data describing heterozygous loss-of-function variants in DCC (n = 61) revealed 63.9% penetrance for mirror movements, 9.8% for ACC, and 5% for both. No significant neurodevelopmental abnormalities were reported among the seven published patients with DCC loss-of-function variants and ACC. Prenatal diagnosis of ACC should prompt a specific anamnesis regarding any neurological disorder, as well as intentional physical examination of both parents aimed to detect mirror movements. In suspicious cases, detection of DCC pathogenic variants might markedly improve the predicted prognosis, alleviate the parental anxiety, and possibly prevent pregnancy termination.

Axon guidance molecules direct growing axons toward their targets, assembling the intricate wiring of the nervous system. One of these molecules, Netrin-1, and its receptor, DCC (deleted in colorectal cancer), has profound effects, in laboratory animals, on the adolescent expansion of mesocorticolimbic pathways, particularly dopamine. Now, a rapidly growing literature suggests that (1) these same alterations could occur in humans, and (2) genetic variants in Netrin-1 and DCC are associated with depression, schizophrenia, and substance use. Together, these findings provide compelling evidence that Netrin-1 and DCC influence mesocorticolimbic-related psychopathological states that emerge during adolescence.

While neural cell transplantation represents a promising therapy for neurodegenerative diseases, the formation of functional networks of transplanted cells with host neurons constitutes one of the challenging steps. Here, we introduce a magnetic guidance methodology that controls neurite growth signaling via magnetic nanoparticles (MNPs) conjugated with antibodies targeting the deleted in colorectal cancer (DCC) receptor (DCC-MNPs). Activation of the DCC receptors by clusterization and subsequent axonal growth of the induced neuronal (iN) cells was performed in a spatially controlled manner. In addition to the directionality of the magnetically controlled axon projection, axonal growth of the iN cells assisted the formation of functional connections with pre-existing primary neurons. Our results suggest magnetic guidance as a strategy for improving neuronal connectivity by spatially guiding the axonal projections of transplanted neural cells for synaptic interactions with the host tissue.

During development, neurons extend axons toward their appropriate synaptic targets to establish functional neuronal connections. The growth cone, a highly motile structure at the tip of the axon, is capable of recognizing extracellular guidance cues and translating them into directed axon outgrowth through modulation of the actin cytoskeleton. Netrin-1 mediates its attractive function through the receptor deleted in colorectal cancer (DCC) to promote axon outgrowth and guidance. The calcium-activated protease calpain is involved in the cleavage of cytoskeletal proteins, which plays an important role during adhesion turnover and cell migration. However, its function during neuronal development is less understood. Here we demonstrate that netrin-1 activated calpain in embryonic rat cortical neurons in an extracellular-regulated kinase 1/2-dependent manner. In addition, we found that netrin-1 stimulation led to an increase in calpain-1 localization in the axon, whereas its endogenous inhibitor calpastatin was decreased in the growth cones of cortical neurons by indirect immunofluorescence. Interestingly, calpain-1 was able to cleave DCC in vitro. Furthermore, netrin-1 induced the cleavage of the cytoskeletal proteins spectrin and focal adhesion kinase concomitantly with the intracellular domain of DCC in a calpain-dependent manner in embryonic rat cortical neurons. Cortical neurons over-expressing calpastatin or calpain-depleted neurons displayed increased basal axon length and were unresponsive to netrin-1 stimulation. Altogether, we propose a novel model whereby netrin-1/DCC-mediated axon outgrowth is modulated by calpain-mediated proteolysis of DCC and cytoskeletal targets in embryonic cortical neurons. Open Science: This manuscript was awarded with the Open Materials Badge For more information see: https://cos.io/our-services/open-science-badges/.

Objective Recently identified mutations of the axon guidance molecule receptor gene, DCC, present an opportunity to investigate, in living human brain, mechanisms affecting neural connectivity and the basis of mirror movements, involuntary contralateral responses that mirror voluntary unilateral actions. We hypothesized that haploinsufficient DCC+/- mutation carriers with mirror movements would exhibit decreased DCC mRNA expression, a functional ipsilateral corticospinal tract, greater "mirroring" motor representations, and reduced interhemispheric inhibition. DCC+/- mutation carriers without mirror movements might exhibit some of these features. Methods The participants (n = 52) included 13 DCC+/- mutation carriers with mirror movements, 7 DCC+/- mutation carriers without mirror movements, 13 relatives without the mutation or mirror movements, and 19 unrelated healthy volunteers. The multimodal approach comprised quantitative real time polymerase chain reaction, transcranial magnetic stimulation (TMS), functional magnetic resonance imaging (fMRI) under resting and task conditions, and measures of white matter integrity. Results Mirror movements were associated with reduced DCC mRNA expression, increased ipsilateral TMS-induced motor evoked potentials, increased fMRI responses in the mirroring M1 and cerebellum, and markedly reduced interhemispheric inhibition. The DCC+/- mutation, irrespective of mirror movements, was associated with reduced functional connectivity and white matter integrity. Interpretation Diverse connectivity abnormalities were identified in mutation carriers with and without mirror movements, but corticospinal effects and decreased peripheral DCC mRNA appeared driven by the mirror movement phenotype. ANN NEUROL 2019;85:433-442.

Low-intensity pulsed ultrasound is found to be effective in axonal regeneration, while the role of ultrasound in axonal growth guidance is still unclear. This study was performed to explore the neuroprotective role of low-intensity pulsed ultrasound (US) both in vitro and in vivo. Primary cultured rat cortical neurons were subjected to 1.0 MHz ultrasound for 5 min every day at intensity of 0, 0.008, 0.12, and 0.21 W/cm2. Our results demonstrated that low-intensity pulsed ultrasound significantly increased neuronal cell viability and inhibited neuronal apoptosis in vitro as determined by fluorescein diacetate assay (FDA) and a TdT-mediated biotin-dUTP nicked-end labeling (TUNEL) assay. Moreover, low-intensity pulsed ultrasound at 0.12 W/cm2 significantly enhanced the axonal growth guidance by activation of netrin-1 and DCC (deleted in colorectal carcinoma) expression as determined by Western blots assay. More interestingly, we further found that low-intensity pulsed ultrasound treatment at 0.21 W/cm2 promoted the functional restoration of rat injured nerves in vivo, decreased hemorrhage, and reversed the injury process by activating positive netrin-1 expression as seen in the immunohistochemistry (IHC) assay. Thus, our study strongly demonstrated that low-intensity pulsed ultrasound activated netrin-1/DCC signaling and further mediated neurite outgrowth. It would be a new approach to nerve regeneration in the future.

It has been reported that Netrin-1 is involved in neuroprotection following injury to the central nervous system. However, the minimal functional domain of Netrin-1 which can preserve the neuroprotection but avoid the major side effects of Netrin remains elusive. Here, we investigated the neuroprotective effect of a peptide E1 derived from Netrin-1′s EGF3 domain (residues 407–422). We found that it interacts with deleted colorectal carcinoma (DCC) to activate focal adhesion kinase phosphorylation exhibiting neuroprotection. The administration of the peptide E1 was able to improve functional recovery through reduced apoptosis in an experimental murine model of intracerebral hemorrhage (ICH). In summary, we reveal a functional sequence of Netrin-1 that is involved in the recovery process after ICH and identify a candidate peptide for the treatment of ICH.

The forebrain hemispheres are predominantly separated during embryogenesis by the interhemispheric fissure (IHF). Radial astroglia remodel the IHF to form a continuous substrate between the hemispheres for midline crossing of the corpus callosum (CC) and hippocampal commissure (HC). DCC and NTN1 are molecules that have an evolutionarily conserved function in commissural axon guidance. The CC and HC are absent in Dcc and Ntn1 knockout mice, while other commissures are only partially affected, suggesting an additional aetiology in forebrain commissure formation. Here, we find that these molecules play a critical role in regulating astroglial development and IHF remodelling during CC and HC formation. Human subjects with DCC mutations display disrupted IHF remodelling associated with CC and HC malformations. Thus, axon guidance molecules such as DCC and NTN1 first regulate the formation of a midline substrate for dorsal commissures prior to their role in regulating axonal growth and guidance across it.

Axons navigate through the embryo to construct a functional nervous system. A missing part of the axon navigation puzzle is how a single axon traverses distinct anatomic choice points through its navigation. The dorsal root ganglia (DRG) neurons experience such choice points. First, they navigate to the dorsal root entry zone (DREZ), then halt navigation in the peripheral nervous system to invade the spinal cord, and then reinitiate navigation inside the CNS. Here, we used time-lapse super-resolution imaging in zebrafish DRG pioneer neurons to investigate how embryonic axons control their cytoskeleton to navigate to and invade at the correct anatomic position. We found that invadopodia components form in the growth cone even during filopodia-based navigation, but only stabilize when the axon is at the spinal cord entry location. Further, we show that intermediate levels of DCC and cAMP, as well as Rac1 activation, subsequently engage an axon invasion brake. Our results indicate that actin-based invadopodia components form in the growth cone and disruption of the invasion brake causes axon entry defects and results in failed behavioral responses, thereby demonstrating the importance of regulating distinct actin populations during navigational challenges. SIGNIFICANCE STATEMENT Correct spatiotemporal navigation of neuronal growth cones is dependent on extracellular navigational cues and growth cone dynamics. Here, we link dcc-mediated signaling to actin-based invadopodia and filopodia dynamics during pathfinding and entry into the spinal cord using an in vivo model of dorsal root ganglia (DRG) sensory axons. We reveal a molecularly-controlled brake on invadopodia stabilization until the sensory neuron growth cone is present at the dorsal root entry zone (DREZ), which is ultimately essential for growth cone entry into the spinal cord and behavioral response.

The netrin‐1/DCC ligand/receptor pair has key roles in central nervous system (CNS) development, mediating axonal, and neuronal navigation. Although expression of netrin‐1 and DCC is maintained in the adult brain, little is known about their role in mature neurons. Notably, netrin‐1 is highly expressed in the adult substantia nigra, leading us to investigate a role of the netrin‐1/DCC pair in adult nigral neuron fate. Here, we show that silencing netrin‐1 in the adult substantia nigra of mice induces DCC cleavage and a significant loss of dopamine neurons, resulting in motor deficits. Because loss of adult dopamine neurons and motor impairments are features of Parkinson’s disease (PD), we studied the potential impact of netrin‐1 in different animal models of PD. We demonstrate that both overexpression of netrin‐1 and brain administration of recombinant netrin‐1 are neuroprotective and neurorestorative in mouse and rat models of PD. Of interest, we observed that netrin‐1 levels are significantly reduced in PD patient brain samples. These results highlight the key role of netrin‐1 in adult dopamine neuron fate, and the therapeutic potential of targeting netrin‐1 signaling in PD., In vivo silencing reveals a pro‐survival role for the developmental axon guidance cue netrin‐1 in the adult mouse substantia nigra, which may be lost in Parkinson's patients and thus offering potential therapeutic options.

Antibodies against contactin-associated protein-like 2 (CASPR2-Abs) have been described in acquired neuromyotonia, limbic encephalitis (LE) and Morvan syndrome (MoS). However, it is unknown whether these constitute one sole spectrum of diseases with the same immunopathogenesis or three distinct entities with different mechanisms.A cluster analysis of neurological symptoms was performed in a retrospective cohort of 56 CASPR2-Abs patients. In parallel, immunological features and human leucocyte antigen (HLA) were studied.Cluster analysis distinguished patients with predominant limbic symptoms (n=29/56) from those with peripheral nerve hyperexcitability (PNH; n=27/56). In the limbic-prominent group, limbic features were either isolated (LE/-; 18/56, 32.1%), or combined with extralimbic symptoms (LE/+; 11/56, 19.6%). Those with PNH were separated in one group with severe PNH and extralimbic involvement (PNH/+; 16/56, 28.6%), resembling historical MoS descriptions; and one group with milder and usually isolated PNH (PNH/-; 11/56, 19.6%). LE/- and LE/+ patients shared immunogenetic characteristics demonstrating a homogeneous entity. HLA-DRB1*11:01 was carried more frequently than in healthy controls only by patients with LE (94.1% vs 18.3%; p=1.3×10Symptoms' distribution supports specific clinical phenotypes without overlap between LE and MoS. The distinct immunogenetic characteristics shared by all patients with LE and the particular oncological and autoimmune associations of MoS suggest two very different aetiopathogenesis.

To analyze the regulatory effect of Netrin-1 in ischemic stroke and its influence on Deleted in Colon Cancer (DCC)/Extracellular Signal-regulated Kinase (ERK) signaling pathway, 20 male rats were selected to construct the rat model of middle cerebral artery occlusion (MCAO), 10 normal rats were selected as healthy controls (Normal Saline (NS)), and they were divided into the MCAO+Netrin-1 group, MCAO group, and NS group according to different treatment schemes. The positive expression of Netrin-1 was detected by immunostaining, magnetic resonance imaging (MRI) was adopted to detect the percentage of rat cerebral infarct volume in the cerebral hemispheres, and Modified Neurological Severity Score (mNSS) was adopted to evaluate postoperative neurological function in rats. Besides, a tunnel staining experiment was applied to detect the apoptosis rate of rat neurons, the sticker removal test was applied to evaluate the postoperative sensory function of rats, and fluorescence staining was adopted to detect the expression of DCC and ERK in rats. The results showed that the percentage of cerebral infarction volume in the cerebral hemispheres of the MCAO+Netrin-1 group was higher than that of the MCAO and NS groups ( P < 0.05 ); in the MCAO+Netrin-1 group, the MCAO mNSS scoring and the time spent in the sticker removal test were lower than the MCAO group ( P < 0.05 ); the apoptosis rate of rats in the MCAO+Netrin-1 group was lower than that in the MCAO group ( P < 0.05 ); the average fluorescence intensity of DCC and p-ERK in the MCAO+Netrin-1 group was higher than that in the MCAO group ( P < 0.05 ); the average fluorescence intensity of p-ERK in the MCAO+Netrin-1 group was higher than that in the MCAO group ( P < 0.05 ). In short, Netrin-1 can effectively reduce the brain tissue damage in rats with ischemic stroke, improve the nerve function and sensory function of rats, and inhibit neuronal cell apoptosis. Netrin-1 can promote DCC expression and ERK phosphorylation, and the EPK signaling pathway may be involved in the antiapoptotic effect of Netrin-1.

Introduction: Colorectal cancer is a leading cause of cancer-related mortality in the United States. Current screening recommendations for individuals aged 50 to 75 years include colonoscopy every 10 years, flexible sigmoidoscopy every 5 years, or annual stool-based testing. Stool-based testing, including fecal immunochemical tests (FITs), are cost effective, easy to perform at home, and noninvasive, yet many patients fail to return testing kits and go unscreened. The purpose of the study was to identify patient characteristics and perceived barriers and facilitators of FIT return. Methods: Patients in a large, federally qualified health center who received a FIT kit order between January 1 and July 1, 2017 were identified. We compared sociodemographic and health characteristics between patients who returned and did not return FITs. We used telephone surveys to nonreturners to identify potential barriers (cost, knowledge, psychosocial factors) and facilitators (prepaid postage, outreach) of FIT kit return. An online survey of clinicians assessed perceived patient barriers and facilitators of colorectal cancer screening. Results: Of the 875 patients who received a FIT order, 435 (49.7%) did not return the kit and 121 of the nonreturners completed a telephone survey. Current smokers had an increased risk of FIT nonreturn compared with never smokers (RR = 1.32; 95% CI, 1.13–1.54). Forgetfulness and lack of motivation were the most common FIT return barriers perceived by both patients and clinicians. Prepaid postage with return address on FIT return envelopes and live call reminders were the most commonly reported facilitators. Barriers and facilitators varied greatest between English- and Spanish-speaking patients. Conclusion: In this study, the most common perceived barriers to return of screening fecal test kits were forgetfulness and lack of motivation. The most common perceived facilitators were live call reminders and postage-paid return envelopes. Understanding barriers and facilitators to FITs may be necessary to enhance cancer screening rates in underserved patient populations.

Colorectal carcinoma (CRC) is a malignancy of epithelial origin in the large bowel. The elucidation of the biological functions of programmed cell death ligand-1 (PD-L1), thymidylate synthase (TYMS), and deleted in colorectal cancer (DCC) biomarkers including their roles in the pathophysiology of CRC - has led to their applications in diagnostic and chemo-pharmaceutics. We investigated whether PD-L1, TYMS, and DCC protein expression in CRC tumors are predictive biomarkers of treatment outcome for CRC patients. The expressions of PD-L1, TYMS, and DCC were evaluated by immunohistochemistry (IHC) in 91 paraffin-embedded samples from patients who underwent colectomy procedure in Hospital Serdang, Selangor, Malaysia. There was high expression of DCC in most cases: 84.6% (77/91). PD-L1 showed low expression in 93.4% (86/91) of cases and high expression in 6.6% (5/91) of cases. Low and high expressions of TYMS were detected in 53.8% (49/91) and 46.2% (42/91) of the CRC cases, respectively. There was a significant association between the TYMS expression and gender (P 0.05); the expression of TYMS was observed at a high level in 76.2% of males and in 23.8% of females. The mean overall survival (OS) was 100 months for the CRC patients evaluated. The OS for patients with high expression of PD-L1 was 22 months. Patients with high expression of TYMS and DCC showed OS of 90 and 96 months, respectively. The results from this study suggest that PD-L1, TYMS, and DCC expression could be used as biomarkers to stratify CRC patients who could benefit from adjuvant therapy.

Male Breast Cancer (MBC) is a rare and aggressive disease that is associated with genetic factors. Mutations in BRCA1 and BRCA2 account for 10% of all MBC cases suggesting that other genetic factors are involved. The aim of the present study is to screen whole BRCA1 and BRCA2 exons using the Ampliseq BRCA panel in Tunisian MBC patients with family history. Furthermore, we performed exome sequencing using the TruSight One sequencing panel on an early onset BRCA negative patient. We showed that among the 6 MBC patients, only one (MBC-F1) harbored a novel frameshift mutation in exon 2 of the BRCA2 gene (c.17-20delAAGA, p.Lys6Xfs) resulting in a short BRCA2 protein of only 6 amino-acids. We selected 9 rare variants after applying several filter steps on the exome sequencing data. Among these variants, and based on their role in breast carcinogenesis, we retained 6 candidate genes (MSH5, DCC, ERBB3, NOTCH3, DIAPH1, and DNAH11). Further studies are needed to confirm the association of the selected genes with family MBC.

Myosin X (Myo X) transports cargos to the tips of filopodia for cell adhesion, migration, and neuronal axon guidance. Deleted in Colorectal Cancer (DCC) is one of the Myo X cargos that is essential for Netrin-1-regulated axon pathfinding. The function of Myo X in axon developmentin vivoand the underlying mechanisms remain elusive. Here, we provide evidence for the role of Myo X in Netrin-1-DCC-regulated axon development in developing mouse neocortex. The knockout (KO) or knockdown (KD) of Myo X in cortical neurons of embryonic mouse brain impairs axon initiation and contralateral branching/targeting. Similar axon deficits are detected in Netrin-1-KO or DCC-KD cortical neurons. Further proteomic analysis of Myo X binding proteins identifies KIF13B (a kinesin family motor protein). The Myo X interaction with KIF13B is induced by Netrin-1. Netrin-1 promotes anterograde transportation of Myo X into axons in a KIF13B-dependent manner. KIF13B-KD cortical neurons exhibit similar axon deficits. Together, these results reveal Myo X-KIF13B as a critical pathway for Netrin-1-promoted axon initiation and branching/targeting.SIGNIFICANCE STATEMENTNetrin-1 increases Myosin X (Myo X) interaction with KIF13B, and thus promotes axonal delivery of Myo X and axon initiation and contralateral branching in developing cerebral neurons, revealing unrecognized functions and mechanisms underlying Netrin-1 regulation of axon development.

The receptor deleted in colorectal cancer (DCC) and its ligand netrin-1 are essential for axon guidance during development and are expressed by neurons in the mature brain. Netrin-1 recruits GluA1-containing α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) and is critical for long-term potentiation (LTP) at CA3-CA1 hippocampal Schaffer collateral synapses, while conditional DCC deletion from glutamatergic neurons impairs hippocampal-dependent spatial memory and severely disrupts LTP induction. DCC co-fractionates with the detergent-resistant component of postsynaptic density, yet is enriched in axonal growth cones that differentiate into presynaptic terminals during development. Specific presynaptic and postsynaptic contributions of DCC to the function of mature neural circuits have yet to be identified. Employing hippocampal subregion-specific conditional deletion of DCC, we show that DCC loss from CA1 hippocampal pyramidal neurons resulted in deficits in spatial memory, increased resting membrane potential, abnormal dendritic spine morphology, weaker spontaneous excitatory postsynaptic activity, and reduced levels of postsynaptic adaptor and signaling proteins; however, the capacity to induce LTP remained intact. In contrast, deletion of DCC from CA3 neurons did not induce detectable changes in the intrinsic electrophysiological properties of CA1 pyramidal neurons, but impaired performance on the novel object place recognition task as well as compromised excitatory synaptic transmission and LTP at Schaffer collateral synapses. Together, these findings reveal specific pre- and post-synaptic contributions of DCC to hippocampal synaptic plasticity underlying spatial memory.

Neuroimmune guidance cues have been shown to play a role in atherosclerosis, but their exact role in human pathophysiology is largely unknown. In the current study, we investigated the role of a c.1769G T variant in Netrin-1 in (premature) atherosclerosis.To determine the effect of the genetic variation, purified Netrin-1, either wild type (wtNetrin-1) or the patient observed variation (mutNetrin-1), was used for migration, adhesion, endothelial barrier function and bindings assays. Expression of adhesion molecules and transcription proteins was analyzed by RT-PCR, Western blot or ELISA. To further delineate how mutNetrin-1 mediates its effect on cell migration, lenti-viral knockdown of UNC5B or DCC was used.Bindings assays revealed a decreased binding capacity of mutNetrin-1 to the receptors UNC5B, DCC and β3-integrin and an increased binding capacity to neogenin, heparin and heparan sulfate compared to wtNetrin-1. Exposure of endothelial cells to mutNetrin-1 resulted in enhanced monocyte adhesion and expression of IL-6, CCL2 and ICAM-1 compared to wtNetrin-1. In addition, mutNetrin-1 lacks the inhibitory effect on the NF-κB pathway that is observed for wtNetrin-1. Moreover, the presence of mutNetrin-1 diminished migration of macrophages and smooth muscle cells. Importantly, UNC5B or DCC specific knockdown showed that mutNetrin-1 is unable to act through DCC resulting in enhanced inhibition of migration.Our data demonstrates that mutNetrin-1 fails to exert anti-inflammatory effects on endothelial cells and more strongly blocks macrophage migration compared to wtNetrin-1, suggesting that the carriers of this genetic molecular variant may well be at risk for premature atherosclerosis.