Cell Adhesion Molecule L1 Research Articles

The Regulatory Roles of Cerebellar Glycosphingolipid Microdomains/Lipid Rafts.

Lipid rafts are dynamic assemblies of glycosphingolipids, sphingomyelin, cholesterol, and specific proteins which are stabilized into platforms involved in the regulation of vital cellular processes. Cerebellar lipid rafts are cell surface ganglioside microdomains for the attachment of GPI-anchored neural adhesion molecules and downstream signaling molecules such as Src-family kinases and heterotrimeric G proteins. In this review, we summarize our recent findings on signaling in ganglioside GD3 rafts of cerebellar granule cells and several findings by other groups on the roles of lipid rafts in the cerebellum. TAG-1, of the contactin group of immunoglobulin superfamily cell adhesion molecules, is a phosphacan receptor. Phosphacan regulates the radial migration signaling of cerebellar granule cells, via Src-family kinase Lyn, by binding to TAG-1 on ganglioside GD3 rafts. Chemokine SDF-1α, which induces the tangential migration of cerebellar granule cells, causes heterotrimeric G protein Goα translocation to GD3 rafts. Furthermore, the functional roles of cerebellar raft-binding proteins including cell adhesion molecule L1, heterotrimeric G protein Gsα, and L-type voltage-dependent calcium channels are discussed.

X-ray structure and function of fibronectin domains two and three of the neural cell adhesion molecule L1.

The cell adhesion molecule L1 (L1CAM, L1 in short) plays crucial roles during neural development, regeneration after injury, synapse formation, synaptic plasticity and tumor cell migration. L1 belongs to the immunoglobulin superfamily and comprises in its extracellular part six immunoglobulin (Ig)-like domains and five fibronectin type III homologous repeats (FNs). The second Ig-like domain has been validated for self- (so-called homophilic) binding between cells. Antibodies against this domain inhibit neuronal migration in vitro and in vivo. The fibronectin type III homologous repeats FN2 and FN3 bind small molecule agonistic L1 mimetics and contribute to signal transduction. FN3 has a stretch of 25 amino acids that can be triggered with a monoclonal antibody, or the L1 mimetics, to enhance neurite outgrowth and neuronal cell migration in vitro and in vivo. To correlate the structural features of these FNs with function, we determined a high-resolution crystal structure of a FN2FN3 fragment, which is functionally active in cerebellar granule cells and binds several mimetics. The structure illustrates that both domains are connected by a short linker sequence allowing a flexible and largely independent organization of both domains. This becomes further evident by comparing the X-ray crystal structure with models derived from Small-Angle X-ray Scattering (SAXS) data for FN2FN3 in solution. Based on the X-ray crystal structure, we identified five glycosylation sites which we believe are crucial for folding and stability of these domains. Our study signifies an advance in the understanding of structure-functional relationships of L1.

Clinical significance of L1CAM expression and its biological role in the progression of oral squamous cell carcinoma.

L1 cell adhesion molecule (L1CAM) has been implicated in the progression and metastasis of numerous cancers. However, the role of L1CAM in oral squamous cell carcinoma (OSCC) is not well characterized. In the present study, the expression of L1CAM was examined in oral tongue squamous cell carcinoma (OTSCC) tissue samples by immunohistochemistry, the clinicopathological significance of L1CAM expression was evaluated by chi‑squared test, and the overall survival (OS) rate was analyzed using Kaplan‑Meier method according to the expression of L1CAM. In addition, it was aimed to elucidate the biological role of L1CAM and the underlying molecular mechanisms by which L1CAM functions in OSCC cells in relation to epithelial‑mesenchymal transition (EMT) and PI3K/AKT/ERK signaling pathways. Thus, the functions of L1CAM on the OSCC cell proliferation, migration and invasion, and the activation of EMT and PI3K/AKT/ERK signaling pathways were investigated invitro. Positive L1CAM expression was found in 32.5% of OTSCC cases and was significantly correlated with high histologic grade, greater depth of invasion, lymph node metastasis, perineural invasion, advanced stage, and survival status. Patients with positive L1CAM expression had significantly lower OS rate. Particularly in patients with early OTSCC, L1CAM expression was strongly associated with worse prognosis. Overexpression of the recombinant human L1CAM protein significantly increased cell proliferation, migration and invasion. By contrast, L1CAM knockdown using small interfering RNA significantly inhibited cell proliferation, migration, invasion and EMT. Moreover, phosphorylated (p)‑PI3K, p‑AKT and p‑ERK expression levels were significantly reduced by L1CAM knockdown. Taken together, the findings of the present study suggested that L1CAM could be a potential prognostic marker and a promising therapeutic target in OSCC.

Mint3 as a Potential Target for Cooling Down HIF-1α-Mediated Inflammation and Cancer Aggressiveness.

Hypoxia-inducible factor-1α (HIF-1α) is a transcription factor that plays a crucial role in cells adapting to a low-oxygen environment by facilitating a switch from oxygen-dependent ATP production to glycolysis. Mediated by membrane type-1 matrix metalloproteinase (MT1-MMP) expression, Munc-18-1 interacting protein 3 (Mint3) binds to the factor inhibiting HIF-1 (FIH-1) and inhibits its suppressive effect, leading to HIF-1α activation. Defects in Mint3 generally lead to improved acute inflammation, which is regulated by HIF-1α and subsequent glycolysis, as well as the suppression of the proliferation and metastasis of cancer cells directly through its expression in cancer cells and indirectly through its expression in macrophages or fibroblasts associated with cancer. Mint3 in inflammatory monocytes enhances the chemotaxis into metastatic sites and the production of vascular endothelial growth factors, which leads to the expression of E-selectin at the metastatic sites and the extravasation of cancer cells. Fibroblasts express L1 cell adhesion molecules in a Mint3-dependent manner and enhance integrin-mediated cancer progression. In pancreatic cancer cells, Mint3 directly promotes cancer progression. Naphthofluorescein, a Mint3 inhibitor, can disrupt the interaction between FIH-1 and Mint3 and potently suppress Mint3-mediated inflammation, cancer progression, and metastasis without causing marked adverse effects. In this review, we will introduce the potential of Mint3 as a therapeutic target for inflammatory diseases and cancers.

The Interactions of the 70 kDa Fragment of Cell Adhesion Molecule L1 with Topoisomerase 1, Peroxisome Proliferator-Activated Receptor γ and NADH Dehydrogenase (Ubiquinone) Flavoprotein 2 Are Involved in Gene Expression and Neuronal L1-Dependent Functions.

The cell adhesion molecule L1 is essential not only for neural development, but also for synaptic functions and regeneration after trauma in adulthood. Abnormalities in L1 functions cause developmental and degenerative disorders. L1's functions critically depend on proteolysis which underlies dynamic cell interactions and signal transduction. We showed that a 70 kDa fragment (L1-70) supports mitochondrial functions and gene transcription. To gain further insights into L1-70's functions, we investigated several binding partners. Here we show that L1-70 interacts with topoisomerase 1 (TOP1), peroxisome proliferator-activated receptor γ (PPARγ) and NADH dehydrogenase (ubiquinone) flavoprotein 2 (NDUFV2). TOP1, PPARγ and NDUFV2 siRNAs reduced L1-dependent neurite outgrowth, and the topoisomerase inhibitors topotecan and irinotecan inhibited L1-dependent neurite outgrowth, neuronal survival and migration. In cultured neurons, L1 siRNA reduces the expression levels of the long autism genes neurexin-1 (Nrxn1) and neuroligin-1 (Nlgn1) and of the mitochondrially encoded gene NADH:ubiquinone oxidoreductase core subunit 2 (ND2). In mutant mice lacking L1-70, Nrxn1 and Nlgn1, but not ND2, mRNA levels are reduced. Since L1-70's interactions with TOP1, PPARγ and NDUFV2 contribute to the expression of two essential long autism genes and regulate important neuronal functions, we propose that L1 may not only ameliorate neurological problems, but also psychiatric dysfunctions.

The KDET Motif in the Intracellular Domain of the Cell Adhesion Molecule L1 Interacts with Several Nuclear, Cytoplasmic, and Mitochondrial Proteins Essential for Neuronal Functions.

Abnormal functions of the cell adhesion molecule L1 are linked to several neural diseases. Proteolytic L1 fragments were reported to interact with nuclear and mitochondrial proteins to regulate events in the developing and the adult nervous system. Recently, we identified a 55 kDa L1 fragment (L1-55) that interacts with methyl CpG binding protein 2 (MeCP2) and heterochromatin protein 1 (HP1) via the KDET motif. We now show that L1-55 also interacts with histone H1.4 (HistH1e) via this motif. Moreover, we show that this motif binds to NADH dehydrogenase ubiquinone flavoprotein 2 (NDUFV2), splicing factor proline/glutamine-rich (SFPQ), the non-POU domain containing octamer-binding protein (NonO), paraspeckle component 1 (PSPC1), WD-repeat protein 5 (WDR5), heat shock cognate protein 71 kDa (Hsc70), and synaptotagmin 1 (SYT1). Furthermore, applications of HistH1e, NDUFV2, SFPQ, NonO, PSPC1, WDR5, Hsc70, or SYT1 siRNAs or a cell-penetrating KDET-carrying peptide decrease L1-dependent neurite outgrowth and the survival of cultured neurons. These findings indicate that L1's KDET motif binds to an unexpectedly large number of molecules that are essential for nervous system-related functions, such as neurite outgrowth and neuronal survival. In summary, L1 interacts with cytoplasmic, nuclear and mitochondrial proteins to regulate development and, in adults, the formation, maintenance, and flexibility of neural functions.

L1CAM Is Not a Predictive Factor in Early-stage Squamous-cell Cervical Cancer.

Our study aimed to assess expression of L1 cell adhesion molecule (L1CAM) in early-stage cervical squamous-cell cancer as a prognostic factor. This retrospective, single-institution study included 154 patients who underwent radical hysterectomy for early-stage squamous cell cervical cancer between 2007 and 2017. Tumor samples from 154 patients were available for L1CAM analysis by immunohistochemistry. Among all patients, radical abdominal hysterectomy was performed in 144 cases. L1CAM expression was positive in 24 tumors (15.6%) of the whole group. In relation to the grade of differentiation and the presence of lymphovascular invasion, L1CAM expression did not show an association (p=0.154 and p=0.306, respectively). The disease-free interval and overall survival also did not significantly differ between L1CAM-positive and L1CAM-negative cases (p=0.427 and p=0.240, respectively). For histopathological characteristics, L1CAM-positive cases had a significantly higher median tumor size (p=0.015). Even in the selected group of 115 cases without nodal infiltration, L1CAM status had no effect on the relapse rate during follow-up. Our study did not confirm the results of previous studies showing L1CAM expression to be a negative prognostic factor in cervical cancer. In our study, increased L1CAM expression in early-stage squamous-cell cervical cancer was not associated with adverse prognosis regarding disease recurrence, disease-free survival, nor overall survival. L1CAM expression was correlated only with the size of the tumor.

Synaptic proteins in neuron-derived extracellular vesicles as biomarkers for Alzheimer's disease: novel methodology and clinical proof of concept.

Blood biomarkers can improve drug development for Alzheimer's disease (AD) and its treatment. Neuron-derived extracellular vesicles (NDEVs) in plasma offer a minimally invasive platform for developing novel biomarkers that may be used to monitor the diverse pathogenic processes involved in AD. However, NDEVs comprise only a minor fraction of circulating extracellular vesicles (EVs). Most published studies have leveraged the L1 cell adhesion molecule (L1CAM) for NDEV immunocapture. We aimed to develop and optimize an alternative, highly specific immunoaffinity method to enrich blood NDEVs for biomarker development. After screening multiple neuronal antigens, we achieved NDEV capture with high affinity and specificity using antibodies against Growth-Associated Protein (GAP) 43 and Neuroligin 3 (NLGN3). The EV identity of the captured material was confirmed by electron microscopy, western blotting, and proteomics. The specificity for neuronal origin was demonstrated by showing enrichment for neuronal markers (proteins, mRNA) and recovery of spiked neuronal EVs. We performed NDEV isolation retrospectively from plasma samples from two cohorts of early AD patients (N = 19 and N = 40) and controls (N = 20 and N = 19) and measured p181-Tau, amyloid-beta (Aβ) 42, brain-derived neurotrophic factor (BDNF), precursor brain-derived neurotrophic factor (proBDNF), glutamate receptor 2 (GluR2), postsynaptic density protein (PSD) 95, GAP43, and syntaxin-1. p181-Tau, Aβ42, and NRGN were elevated in AD samples, whereas proBDNF, GluR2, PSD95, GAP43, and Syntaxin-1 were reduced. Differences for p181-Tau, proBDNF, and GluR2 survived multiple-comparison correction and were correlated with cognitive scores. A model incorporating biomarkers correctly classified 94.7% of AD participants and 61.5% of control participants. The observed differences in NDEVs-associated biomarkers are consistent with previous findings. NDEV isolation by GAP43 and NLGN3 immunocapture offers a robust novel platform for biomarker development in AD, suitable for large-scale validation.

Interpretable prognostic modeling of endometrial cancer

Endometrial carcinoma (EC) is one of the most common gynecological cancers in the world. In this work we apply Cox proportional hazards (CPH) and optimal survival tree (OST) algorithms to the retrospective prognostic modeling of disease-specific survival in 842 EC patients. We demonstrate that linear CPH models are preferred for the EC risk assessment based on clinical features alone, while interpretable, non-linear OST models are favored when patient profiles can be supplemented with additional biomarker data. We show how visually interpretable tree models can help generate and explore novel research hypotheses by studying the OST decision path structure, in which L1 cell adhesion molecule expression and estrogen receptor status are correctly indicated as important risk factors in the p53 abnormal EC subgroup. To aid further clinical adoption of advanced machine learning techniques, we stress the importance of quantifying model discrimination and calibration performance in the development of explainable clinical prediction models.

L1CAM is required for early dissemination of fallopian tube carcinoma precursors to the ovary

Most ovarian high-grade serous carcinomas (HGSC) arise from Serous Tubal Intraepithelial Carcinoma (STIC) lesions in the distal end of the fallopian tube (FT). Formation of STIC lesions from FT secretory cells leads to seeding of the ovarian surface, with rapid tumor dissemination to other abdominal structures thereafter. It remains unclear how nascent malignant cells leave the FT to colonize the ovary. This report provides evidence that the L1 cell adhesion molecule (L1CAM) contributes to the ability of transformed FT secretory cells (FTSEC) to detach from the tube, survive under anchorage-independent conditions, and seed the ovarian surface. L1CAM was highly expressed on the apical cells of STIC lesions and contributed to ovarian colonization by upregulating integrins and fibronectin in malignant cells and activating the AKT and ERK pathways. These changes increased cell survival under ultra-low attachment conditions that mimic transit from the FT to the ovary. To study dissemination to the ovary, we developed a tumor-ovary co-culture model. We showed that L1CAM expression was important for FT cells to invade the ovary as a cohesive group. Our results indicate that in the early stages of HGSC development, transformed FTSECs disseminate from the FT to the ovary in a L1CAM-dependent manner.

Effects of L1 adhesion molecule agonistic mimetics on signal transduction in neuronal functions

The L1 cell adhesion molecule plays an essential role in neural development and repair. It is not only a ‘lock and key’ recognition molecule, but an important signal transducer that stimulates regenerative-beneficial cellular functions such as neurite outgrowth, neuronal cell migration, survival, myelination, and synapse formation. Triggering L1 functions after neurotrauma improves functional recovery. In addition, loss-of-function mutations in the L1 gene lead to the L1 syndrome, a rare, X-linked neurodevelopmental disorder with an incidence of approximately 1:30,000 in newborn males. To use L1 for beneficial functions, we screened small compound libraries for L1 agonistic mimetics that trigger L1 functions and improve conditions in animal models of neurotrauma and the L1 syndrome. To understand the mechanisms underlying these functions, it is important to gain a better understanding of L1-dependent cellular signaling that is triggered by the L1 agonistic mimetics. We tested the cell signaling features of L1 agonistic mimetics that contribute to neurite outgrowth and neuronal migration. Our findings indicates that L1 agonistic mimetics trigger the same cell signaling pathways underlying neurite outgrowth, but only the L1 mimetics tacrine, polydatin, trimebutine and honokiol trigger neuronal migration. In contrast, the mimetics crotamiton and duloxetine did not affect neuronal migration, thus limiting their use in increasing neuronal migration, leaving open the question of whether this is a desired or not desired feature in the adult.

Impact and mechanism of CHL1 in insulin resistant adipocytes and insulin resistant mouse model induced by high glucose and high fat

Objective: To investigate the role and mechanism of cell adhesion molecule L1 like (CHL1) in insulin resistant adipocytes and insulin resistant mouse model induced by high glucose and high fat. Methods: The 3T3-L1 preadipocytes were randomly divided into control group (transfected with empty vector) and CHL1 overexpression group (transfected with CHL1 vector), cells were then induced to mature adipocytes by insulin, and insulin resistance was then induced by high sugar and high fat. The glucose content was measured to determine the glucose consumption of cells from the two groups. Protein expression levels of CHL1 and glucose transporter 4 (GLUT4), serine/threonine protein kinase (AKT) phosphorylation levels were detected by Western blot (WB), the mRNA expression levels of TNF-α and IL-6 were detected by real-time quantitative PCR (RT-qPCR). 24 C57BL/6 adult male mouse were randomly divided into conventional diet group (regular group), high-fat diet group (high-fat group), empty vector overexpression+high-fat group and CHL1 overexpression+high-fat group (n=6 each group). CHL1 overexpression was induced by tail vein injection of lentivirus. Four months later, mice were sacrificed, body weight was determined, and the epididymal white adipose tissue was collect. Hematoxylin-eosin staining (HE) was used to observe the pathology of mouse epididymal white adipose tissue, the expression of CHL1 was evaluated by immunohistochemical staining(IHC), RT-qPCR was used to detect the mRNA expression levels of CHL1, TNF-α and IL-6 in mouse epididymal white adipose tissue. Results: In vitro, glucose consumption was significantly higher in the CHL1 overexpression group than in the control group (P<0.05), and the protein expressions of CHL1 and GLUT4 were higher in the CHL1 overexpression group than those in the control group (P<0.01), and the mRNA expressions levels of TNF-α and IL-6 were lower in the CHL1 overexpression group than those in the control group (P<0.01). In vivo, the body weight and epididymal white adipose tissue of mouse were higher in the high-fat group and the empty vector overexpression+high-fat group than those in the conventional group (P<0.01), which were lower in the CHL1 overexpression+high fat group than in the empty vector overexpression+high fat group (P<0.01). HE results showed that the volume of epididymal white adipocytes was larger in the high-fat group and the overexpression control+high-fat group than that in the conventional group, which was smaller in the CHL1 overexpression+high fat group than in the empty vector overexpression+high fat group (P<0.01). The mRNA expression levels of IL-6 and TNF-α in epididymal white adipose tissue of mice were higher in the high-fat group and the empty vector overexpression+high-fat group than those in the conventional group (P<0.01), which were lower in the CHL1 overexpression+high fat group than in the empty vector overexpression+high fat group (P<0.05). IHC results showed that protein expression of CHL1 in epididymal white adipose tissue was lower in the high-fat group and the empty vector overexpression+high-fat group than in regular group, which was upregulated in the CHL1 overexpression+high fat group than in the empty vector overexpression+high-fat group (P<0.01). RT-qPCR results showed that mRNA expression of CHL1 in epididymal white adipose tissue was lower in the high-fat group and the empty vector overexpression+high-fat group than in regular group (P<0.01), which was higher in the CHL1 overexpression+high fat group than in the empty vector overexpression+high fat group (P<0.01). Conclusion: Overexpression of CHL1 can improve insulin resistance in adipocytes and mouse insulin resistance model induced by high glucose and high fat, and the beneficial effects might be mediated by the inhibition of AKT activation and the reduction of related inflammatory responses.

L1CAM expression in either metastatic brain lesion or peripheral blood is correlated with peripheral platelet count in patients with brain metastases from lung cancer.

Systemic immune-inflammation states across the heterogeneous population of brain metastases from lung cancer are very important, especially in the context of complex brain-immune bidirectional communication. Previous studies from our team and others have shown that the L1 cell adhesion molecule (L1CAM) is deeply involved in the aggressive phenotype, immunosuppressive tumor microenvironment (TME), and metastasis during multiple malignancies, which may lead to an unfavorable outcome. However, little is known about the relationship between the L1CAM expression and the systemic immune-inflammation macroenvironment beyond the TME in brain metastases from lung cancer. Two cohorts of patients with brain metastases from lung cancer admitted to the National Cancer Center, Cancer Hospital of Chinese Academy of Medical Sciences, were studied in the present research. The L1CAM expression in cranial metastatic lesions by immunohistochemistry was explored in patients treated with neurosurgical resection, whereas the L1CAM expression in peripheral blood by ELISA was tested in patients treated with non-surgical antitumor management. Furthermore, based on peripheral blood cell counts in the CBC test, six systemic immune-inflammation biomarkers [neutrophil count, lymphocyte count, platelet count, systemic immune-inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio] were calculated. Then, the relationship between the L1CAM expression and these systemic immune-inflammation biomarkers was analyzed. In addition, these systemic immune-inflammation biomarkers were also used to compare the systemic immune-inflammation states in two cohorts of patients with brain metastases from lung cancer. Positive L1CAM expressions in the metastatic brain lesions were accompanied with significantly increased peripheral platelet counts in patients treated with neurosurgical tumor resection (P < 0.05). Similarly, in patients treated with non-surgical antitumor management, L1CAM expressions in the peripheral blood were positively correlated with peripheral platelet counts (P < 0.05). In addition, patients prepared for neurosurgical tumor resection were presented with poorer systemic immune-inflammation states in comparison with the one with non-surgical antitumor management, which was characterized by a significant increase in peripheral neutrophil counts (P < 0.01), SII (P < 0.05), and NLR (P < 0.05) levels. The L1CAM expression in either the metastatic brain lesion or peripheral blood is positively correlated with the peripheral platelet count in patients with brain metastases from lung cancer. In addition, brain metastases that are prepared for neurosurgical tumor resection show poor systemic immune-inflammation states.

Could soluble L1 cell adhesion molecule (sL1CAM) in serum be a new biomarker for endometrial cancer?

The aim of this study is to evaluate the place of serum soluble L1 cell adhesion molecule (sL1CAM) level in the diagnosis of endometrial cancer and its relationship with clinicopathological features. This cross-sectional study was performed with 146 patients who underwent endometrial biopsy and whose pathology results were reported as benign endometrial changes (n = 30), endometrial hyperplasia (n = 32) or endometrial cancer (n = 84). The sL1CAM level between the groups was compared. The relationship between clinicopathological features and serum sL1CAM was evaluated in patients with endometrial cancer. The mean serum sL1CAM level in patients with endometrial cancer was significantly higher than in patients without cancer. The sL1CAM value was statistically significantly higher in the group with endometrial cancer, than the group with endometrial hyperplasia (p < 0.001) and the group with benign endometrial changes (p < 0.001). There was no statistically significant difference in terms of sL1CAM between the group of patients with endometrial hyperplasia and the group of patients with benign endometrial changes (p = 0.954). sL1CAM value in type 2 endometrial cancer was statistically significantly higher than Type1 (p = 0.019). High sL1CAM level in patients with type 1 cancer was associated with poor clinicopathological features. However, no correlation was observed between clinicopathological features and serum sL1CAM level in type 2 endometrial cancers. Serum sL1CAM may be an important marker for evaluating the diagnosis and prognosis of endometrial cancer in the future. There may be a relationship between increased serum sL1CAM level in type 1 endometrial cancers and poor clinicopathological features.

Small extracellular vesicles in plasma reveal molecular effects of modified Mediterranean-ketogenic diet in participants with mild cognitive impairment.

Extracellular vesicles have emerged as a less-invasive nano-tool for discovering biomarkers of Alzheimer's disease and related dementia. Here, we analysed different neuron-enriched extracellular vesicles from plasma to predict response and molecular mechanisms of ketogenic diet's efficacy in mild cognitive impairment participants. The study was a randomized crossover design in which cognitively normal and mild cognitive impairment participants consumed a modified Mediterranean-ketogenic diet or American Heart Association diet for 6 weeks, followed by other diet after washout. L1 cell adhesion molecule, synaptophysin and neural cell adhesion molecule surface markers were used to enrich for neuron-secreted small extracellular vesicles (sEVL1CAM, sEVSYP and sEVNCAM). For the first time, we have presented multiple evidences, including immunogold labelling/transmission electron microscopy, clusters of differentiation 63-ELISA-based assay, confocal microscopy fluorescent images and flow cytometry data confirming the presence of L1 cell adhesion molecule on the surface of sEVL1CAM, validating purity and relative abundance of sEVL1CAM in the plasma. Cargo analysis of sEVL1CAM showed that modified Mediterranean-ketogenic diet intervention reduces amyloid beta 1-42 (50.3%, P = 0.011), p181-tau (34.9%, P = 0.033) and neurofilament light (54.2%, P = 0.020) in mild cognitive impairment participants. Moreover, sEVL1CAMshowed better sensitivity compared with CSF in analysing increased glutamate (6-folds, P < 0.0001) from mild cognitive impairment participants following modified Mediterranean-ketogenic diet intervention. sEVL1CAM characterization also suggested that modified Mediterranean-ketogenic diet differentially targets the expression of various glutamate receptors-glutamate receptor ionotropic NMDA1, glutamate receptor ionotropic NMDA2A, glutamate receptor ionotropic NMDA2B and glutamate receptor ionotropic AMPA type subunit 1. Importantly, these sEVL1CAM measures strongly correlated with corresponding clinical CSF biomarkers (neurogranin, amyloid beta 1-42, neurofilament light and tau). Furthermore, sEVL1CAM were loaded with less advanced glycation endproducts and exhibited anti-inflammatory activity following modified Mediterranean-ketogenic diet intervention. Most importantly, the expression of monocarboxylate transporter 2 on the surface of sEVL1CAM predicted the amyloid beta 1-42 response to modified Mediterranean-ketogenic diet intervention (area under the curve = 0.87, P = 0.0044) and offered a novel screening tool to identify participants responsive to this dietary intervention. Finally, sEVL1CAM, sEVSYP and sEVNCAM showed significantly high concordance in analysing amyloid beta 1-42 (Pearson correlation coefficient ≥ 0.63, P < 0.01) and neurofilament light (Pearson correlation coefficient ≥ 0.49, P < 0.05). Together, small extracellular vesicles in plasma offers promise in assessing the efficacy of dietary/therapeutic intervention against mild cognitive impairment/Alzheimer's disease.

The Influence of Prenatal Exposure to Quetiapine Fumarate on the Development of Dopaminergic Neurons in the Ventral Midbrain of Mouse Embryos.

The effects of second-generation antipsychotics on prenatal neurodevelopment, apoptotic neurodegeneration, and postnatal developmental delays have been poorly investigated. Even at standard doses, the use of quetiapine fumarate (QEPF) in pregnant women might be detrimental to fetal development. We used primary mouse embryonic neurons to evaluate the disruption of morphogenesis and differentiation of ventral midbrain (VM) neurons after exposure to QEPF. The dopaminergic VM neurons were deliberately targeted due to their roles in cognition, motor activity, and behavior. The results revealed that exposure to QEPF during early brain development decreased the effects of the dopaminergic lineage-related genes Tyrosine hydroxylase (Th), Dopamine receptor D1 (Drd1), Dopamine transporter (Dat), LIM homeobox transcription factor 1 alfa (Lmx1a), and Cell adhesion molecule L1 (Chl1), and the senescent dopaminergic gene Pituitary homeobox 3 (Pitx3). In contrast, Brain derived neurotrophic factor (Bdnf) and Nuclear receptor-related 1 (Nurr1) expressions were significantly upregulated. Interestingly, QEPF had variable effects on the development of non-dopaminergic neurons in VM. An optimal dose of QEPF (10 µM) was found to insignificantly affect the viability of neurons isolated from the VM. It also instigated a non-significant reduction in adenosine triphosphate formation in these neuronal populations. Exposure to QEPF during the early stages of brain development could also hinder the formation of VM and their structural phenotypes. These findings could aid therapeutic decision-making when prescribing 2nd generation antipsychotics in pregnant populations.

Analysis of tumour markers in esophageal carcinoma with different age groups

BackgroundEsophageal cancer has been reported in various countries, including Saudi Arabia, India and United States. Many biomarkers have been used to detect cancers at an early stage to improve the survival rate of esophageal cancer. MethodsThe present study investigated the biomarkers, biglycan, myeloperoxidase, cytokine (TNF-α, IFN-γ, IL-10 and IL-12) and carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC) and carbohydrate antigen L1 cell adhesion molecule from the tumour and non-tumour samples. ResultsThe increased amount of circulatory biglycan level was detected using the ELISA method in tumour cases compared to control samples (p < 0.001). The expression of biglycan was high in certain tumour cases and was statistically significant (p < 0.01). The variation of myeloperoxidase markers in control and experimental subjects were statistically significant (p < 0.01). Among cancer patients, elevated levels of carcinoembryonic antigen (28.3 ± 1.2 ng/ml and 30.3 ± 1.1 ng/ml), squamous cell carcinoma antigen (5.3 ± 1.1 ng/ml and 4.9 ± 0.5) and carbohydrate antigen 19–9 (18.3 ± 1.1 ng/ml and 15.1 ± 2.6 ng/ml) were detected in male and female cases (p < 0.001). In the normal tissues, the expression of L1 cell adhesion molecule was high and was expressed in low amount in tumour tissues in both male and female individuals (<0.001). ConclusionThese biomarkers are useful for the early diagnosis of esophageal cancer.

Functional Diversity of Neuronal Cell Adhesion and Recognition Molecule L1CAM through Proteolytic Cleavage.

The neuronal cell adhesion and recognition molecule L1 does not only ‘keep cells together’ by way of homophilic and heterophilic interactions, but can also promote cell motility when cleaved into fragments by several proteases. It has largely been thought that such fragments are signs of degradation. Now, it is clear that proteolysis contributes to the pronounced functional diversity of L1, which we have reviewed in this work. L1 fragments generated at the plasma membrane are released into the extracellular space, whereas other membrane-bound fragments are internalised and enter the nucleus, thus conveying extracellular signals to the cell interior. Post-translational modifications on L1 determine the sequence of cleavage by proteases and the subcellular localisation of the generated fragments. Inside the neuronal cells, L1 fragments interact with various binding partners to facilitate morphogenic events, as well as regenerative processes. The stimulation of L1 proteolysis via injection of L1 peptides or proteases active on L1 or L1 mimetics is a promising tool for therapy of injured nervous systems. The collective findings gathered over the years not only shed light on the great functional diversity of L1 and its fragments, but also provide novel mechanistic insights into the adhesion molecule proteolysis that is active in the developing and diseased nervous system.

Hypoxia and Ezrin Expression in Primary Melanoma Have High Prognostic Relevance.

Hypoxia affects tumor aggressiveness and activates pathways associated with epithelial mesenchymal transition (EMT) which are crucial for tumor progress. In this study, the correlation of hypoxia and EMT with sentinel lymph node status and tumor-specific survival was investigated in primary melanomas. CD34 for capillary count and Hypoxia inducible factor-1α (HIF-1α) as hypoxia indicators as well as Ezrin and L1-Cell Adhesion Molecule (L1CAM), both critical proteins contributing to EMT, were analyzed using immunohistochemistry in 49 melanoma patients with long follow-up (F/U, mean 110 months; range 12–263 months). We found a significant correlation between Breslow tumor thickness and Ezrin expression (p = 0.018). L1CAM expression in primary melanoma was significantly associated with HIF-1α expression (p < 0.0001) and sentinel lymph node metastasis (p = 0.011). Furthermore, low capillary count, reflecting hypoxic condition, was significantly associated with Ezrin expression (p = 0.047) and decreased tumor-specific survival (p = 0.035). In addition, patients with high Ezrin expression in their primary melanoma had a dramatic loss of life early in their F/U period (mean survival time 29 months; range 15–44 month). Our results highlight the relevance of Ezrin, L1CAM and HIF-1α as prognostic markers in melanoma patients. Additionally, we demonstrate that hypoxia in primary melanoma affects EMT and is at least partly responsible for early metastatic dissemination.

Transcriptomics of circulating neutrophils in dairy cows with subclinical hypocalcemia.

Hypocalcemia is closely associated with inflammatory diseases in dairy cows. Recent research has underscored the key role of calcium in the adaptations of the innate immune system during this period. The main objective in the present study was to compare the transcriptome profiles and analyze differences in the expression of neutrophil (PMNL) immune function-related genes and calcium binding-related genes in hypocalcemic cows. At 2 days postpartum, a concentration >2.10 mmol Ca2+/L was used to classify cows as controls (CON), and a concentration <2.00 mmol Ca2+/L used to classify cows as low-calcium (LCAL) (n = 8 in each group). A routine medical examination was conducted by the attending veterinarian to ensure there were no other complications and that the blood β-hydroxybutyrate was <1.2 mmol/L. Blood was collected from the tail vein (20 mL) to isolate PMNL, and 5 cows in each group were used for RNA sequencing and statistical analysis of gene expression differences. Transcriptome RNA-seq sequencing analysis was via omicsstudio using the R package edgeR. GO and KEGG enrichment analysis were used for bioinformatics. The remaining 3 cows in each group were used for validation of RNA sequencing data via quantitative PCR, which confirmed the observed responses. Compared with CON, 158 genes in LCAL were significantly up-regulated and 296 genes were down-regulated. The downregulation of Interleukin-12 (CXCL12), Tubulin beta chain (TUBB1), L1 cell adhesion molecule (L1CAM), and Myeloperoxidase (MPO) indicated a decrease in immune function of PMNL in LCAL cows. The decreased expression of calcium-binding pathway-related genes in PMNL of LCAL cows indicated a decrease in immune function of PMNL likely related to calcium ions. For example, cartilage acid protein 1 (CRTAC1) and calcium/calmodulin-dependent kinase 4 (CAMK4) were significantly reduced in LCAL cows. The upregulation of Cyclin dependent kinase inhibitor 1A (CDKN1A), Perforin 1 (PRF1), and Homeodomain interacting protein kinase 3 (HIPK3) indicated that LCAL led to greater cell apoptosis and senescence. Overall, the analyses indicated that the reduction in PMNL immune function during hypocalcemia is associated with downregulation of intracellular Ca2+ related genes and upregulation of genes controlling apoptosis and senescence. Together, these alterations contribute to an immunosuppressive state during the transition period.