Expression of E-cadherin, Slug and NCAM and its relationship to tumor invasiveness in patients with acromegaly

Pituitary adenomas account for 10-15% of primary intracranial tumors. Growth hormone (GH)-secreting adenomas account for 13% of all pituitary adenomas and cause acromegaly. These tumors can be aggressive, invade surrounding structures and are highly recurrent. The objective of this study was to evaluate E-cadherin, Slug and neural cell adhesion molecule (NCAM) expression in GH-secreting pituitary adenomas and its relationship to tumor invasiveness. A cross-sectional study of patients who underwent hypophysectomy due to GH-secreting pituitary adenoma from April 2007 to December 2014 was carried out. The medical records were reviewed to collect clinical data. Immediately after surgery, tumor samples were frozen in liquid nitrogen and stored in a biofreezer at -80°C for assessment of E-cadherin 1 (CDH1), SLUG (SNAI2), and NCAM (NCAM1) by real-time PCR. The samples were fixed in formalin and embedded in paraffin for immunohistochemical analysis of E-cadherin and NCAM. Thirty-five patients with acromegaly were included in the study. Of these, 65.7% had invasive tumors. Immunohistochemically, E-cadherin was expressed in 96.7% of patients, and NCAM in 80% of patients. There was no statistically significant relationship between tumor grade or invasiveness and immunohistochemical expression of these markers. Regarding gene expression, 50% of cases expressed CDH1, none expressed SNAI2, and 53.3% expressed NCAM1. There was no statistically significant relationship between tumor grade or invasiveness and gene expression of CDH1, SNAI2, and NCAM1. The absence of Slug overexpression and of E-cadherin and NCAM suppression suggests that expression of these markers is not associated with tumor invasiveness in GH-secreting pituitary adenomas.

Usefulness of End-to-Side Bridging Anastomosis of Sural Nerve to Tibial Nerve: An Experimental Research

OBJECTIVE: Repair of sensorial nerve defect is an important issue on peripheric nerve surgery. The aim of the present study was to determine the effects of sensory-motor nerve bridging on the denervated dermatomal area, in rats with sensory nerve defects, using a neural cell adhesion molecule (NCAM). METHODS: We compared the efficacy of end-to-side (ETS) coaptation of the tibial nerve for sural nerve defect repair, in 32 Sprague-Dawley rats. Rats were assigned to 1 of 4 groups: group A was the sham operated group, group B rats had sural nerves sectioned and buried in neighboring muscles, group C experienced nerve sectioning and end-to-end (ETE) anastomosis, and group D had sural nerves sectioned and ETS anastomosis was performed using atibial nerve bridge. Neurological evaluation included the skin pinch test and histological evaluation was performed by assessing NCAM expression in nerve terminals. RESULTS: Rats in the denervated group yielded negative results for the skin pinch tests, while animals in the surgical intervention groups (group C and D) demonstrated positive results. As predicted, there were no positively stained skin specimens in the denervated group (group B); however, the surgery groups demonstrated significant staining. NCAM expression was also significantly higher in the surgery groups. However, the mean NCAM values were not significantly different between group C and group D. CONCLUSION: Previous research indicates that ETE nerve repair is the gold standard for peripheral nerve defect repair. However, ETS repair is an effective alternative method in cases of sensorial nerve defect when ETE repair is not possible.

Influence of sevoflurane anesthesia on expression of GAP-43 and NCAM in hippocampal neurons of neonatal rats / 中华麻醉学杂志

Objective To evaluate the influence of sevoflurane anesthesia on the expression of growth-associated protein 43 (GAP-43) and neural cell adhesion molecule (NCAM) in hippocampal neurons of neonatal rats.Methods Thirty-six pathogen-free Sprague-Dawley rats,aged 7 weeks,weighing 15-20 g,were randomly divided into 4 groups (n =9 each) using a random number table:control group (C group),1.5％ sevoflurane 6 h group (L group),3％ sevoflurane 2 h group (H1 group) and 3％ sevoflurane 6 h group (H2 group).Group L inhaled 1.5％ sevoflurane in oxygen for 6 h.H1 and H2 groups inhaled 3％ sevoflurane in oxygen for 2 and 6 h,respectively.Group C inhaled 30％ oxygcn only.When the neonatal rats were 14 days old,the rats underwent Morris water maze test for 7 consecutive days.Place navigation and spatial probe tests were carried out.After the end of Morris water maze test,the rats were sacrificed,and the hippocampus was obtained for determination of the expression of GAP-43 and NCAM in hippocampal neurons.Results Compared with group C,the escape latency was significantly prolonged,the time of staying at the original platform quadrant was shortened,and the expression of GAP-43 was down-regulated in L,H1 and H2 groups,and the frequency of crossing the original platform was decreased in L and H2 groups.There was no significant difference in NCAM expression among the four groups.Conclusion The mechanism by which sevoflurane anesthesia decreases the cognitive function may be related to down-regulated expression of GAP-43,but not related to NCAM expression in hippocampal neurons of neonatal rats.

The miR-200a influences the migration and invasion abilities of glioma cells by targeting NCAM1 gene / 肿瘤

Objective: To investigate the effects of miR(microRNA)-200a on migration and invasion abilities of glioma cells, and to explore its possible mechanism. Methods: Differential expression levels of miR-200a in glioma U87 cells were achieved by transfecting with hsa-miR-200a mimic, hsa-miR-200a inhibitor or hsa-miR-negative control by Lipofectamine™ 2000. The migration and invasion abilities of U87 cells were detected by wound-healing assay and Transwell invasion assay, respectively. Bioinformatics software was used to predict downstream target genes of miR-200a and their binding sites. The potential target genes were verified by Luciferase Reporter Assay and Western blotting. Results: Exogenous overexpression of miR-200a could promote migration and invasion abilities of U87 cells (P < 0.05), while miR-200a inhibitors could generate the opposite results (P < 0.05). Luciferase Reporter Assay and Western blotting revealed that hsa-miR-200a negatively regulated the protein expression of NCAM1 (neural cell adhesion molecule 1) gene which was regarded as the target gene. Conclusion: The miR-200a can promote the migration and invasion abilities of glioma U87 cells, in which NCAM1 may be one of the target genes. Copyright © 2013 by TUMOR.

Features of the NCAM+c-Kit+ subset of hepatic progenitor cells in intrahepatic cholangiocarcinoma / 中华肝胆外科杂志

Objective To identify the features of the NCAM+ c-Kit+ subset of hepatic progenitor cells in the intrahepatic cholangiocarcinoma (ICC) cell line RBE.Method Magnetic activated cell sorting was used to isolate NCAM+ c-Kit+/NCAM-c-Kit-subset cells,which were tested for hepatic progenitor cell properties and proliferation,colony formation,and invasive abilities in nude mice.Resuits The cell proliferation ability of NCAM+c-Kit+ subset cells was stronger than that of NCAMc-Kit-subset cells (P＜0.01).In serum-free condition,the number of colonies formed by NCAM+c-Kit+ subset cells was more than that of NCAM-c-Kit-cells (P＜0.01).1 × 104 NCAM+c-Kit+ cells were enough to form tumors in nude mice after subcutaneous inoculation for two weeks,while 1 × 106 NCAM-c-Kit-cells were necessary to form tumors for three weeks.The tumor formation rate of NCAM+c-Kit+ cells was higher than that of NCAM-c-Kit-cells (P=0.04).Conclusions It is possible that NCAM+c-Kit+ subset cells in RBE have the properties of hepatic progenitor cells,and NCAM combined with c-Kit might be a valuable marker for isolating and purifying ICC stem/progenitor cells.

Altered Neuronal Markers Following Treatment with Mood Stabilizer and Antipsychotic Drugs Indicate an Increased Likelihood of Neurotransmitter Release

OBJECTIVE: Given the ability of mood stabilizers and antipsychotics to promote cell proliferation, we wanted to determine the effects of these drugs on neuronal markers previously reported to be altered in subjects with psychiatric disorders. METHODS: Male Sprauge-Dawley rats were treated with vehicle (ethanol), lithium (25.5 mg per day), haloperidol (0.1 mg/kg), olanzapine (1.0 mg/kg) or a combination of lithium and either of the antipsychotic drugs for 28 days. Levels of cortical synaptic (synaptosomal associated protein-25, synaptophysin, vesicle associated protein and syntaxin) and structural (neural cell adhesion molecule and alpha-synuclein) proteins were determined in each treatment group using Western blots. RESULTS: Compared to the vehicle treated group; animals treated with haloperidol had greater levels of synaptosomal associated protein-25 (p<0.01) and neural cell adhesion molecule (p<0.05), those treated with olanzapine had greater levels of synaptophysin (p<0.01) and syntaxin (p<0.01). Treatment with lithium alone did not affect the levels of any of the proteins. Combining lithium and haloperidol resulted in greater levels of synaptophysin (p<0.01), synaptosomal associated protein-25 (p<0.01) and neural cell adhesion molecule (p<0.01). The combination of lithium and olanzapine produced greater levels of synaptophysin (p<0.01) and alpha-synuclein (p<0.05). CONCLUSION: Lithium alone had no effect on the neuronal markers. However, haloperidol and olanzapine affected different presynaptic markers. Combining lithium with olanzapine additionally increased alpha-synuclein. These drug effects need to be taken into account by future studies examining presynaptic and neuronal markers in tissue from subjects with psychiatric disorders.

Neural cell adhesion molecule (NCAM) induces neuronal phenotype acquisition in dominant negative MEK1-expressing hippocampal neural progenitor cells

It has been shown that neural cell adhesion molecule (NCAM)-induced neuronal differentiation is extracellular signal-regulated kinase (ERK)-dependent. However, an involvement of the mitogen activated protein kinase (MAPK) kinase (MEK), an upstream kinase of ERK, has not been directly demonstrated in this process. Therefore, we investigated whether the MEK1 plays a critical role in the NCAM-induced neuronal differentiation of hippocampal neural progenitor cells (NPCs). NPCs were transiently transfected with expression plasmids encoding activated or dominant negative (DN) forms of MEK1. The expression of DN MEK1 inhibited neuronal phenotype acquisition and soluble NCAM rescued the defect in the neuronal phenotype acquisition in DN-MEK1-transfected cells, suggesting that NCAM might contribute to the neuronal differentiation via distinct, parallel pathways including the MEK pathway. In cells expressing wild type MEK1 or constitutively active MEK1 on the other hand, the percentage of cells positive for beta-tubulin type III (Tuj1), a marker for early postmitotic neurons, was higher than seen in vector-transfected cells. These results suggest that the activation of MEK1 is required for obtaining neuronal phenotype in NPCs.

Neural cell adhesion molecule (NCAM) promotes the differentiation of hippocampal precursor cells to a neuronal lineage, especially to a glutamatergic neural cell type

Rat hippocampal precursor cells isolated from hippocampi of embryonic day 16.5 (E16.5) rat embryos were found to proliferate in the presence of basic fibroblast growth factor. Addition of soluble neural cell adhesion molecule (NCAM) to these precursor cells reduced cell proliferation in a dose dependent manner and enhanced the induction of precursor cells' differentiation to the neuronal lineage. Given these findings that NCAM induces the differentiation of hippocampal precursor cells, we investigated possible effects of NCAM on the expression of basic helix-loop-helix (bHLH) transcription factors during the differentiation. Soluble NCAM upregulated the transcription of bHLH transcription factors, neurogenin1 and NeuroD, but decreased HES5. Western blot analysis showed that NCAM increased the expression levels of CaMKII, p-MAPK, GluR1 and NR1 but decreased p-STAT3. These results support a role for NCAM in the inhibition of proliferation and the induction of neural differentiation of hippocampal neural precursor cells, and act as developmental regulators of the bHLH families, ultimately leading to the generation of glutamatergic neural cell types in the differentiation of hippocampal precursor cells.

Effects of chronic pain on spatial learning ability and expression of neuronal cell adhesion molecule in hippocampus in neonatal rats / 中华麻醉学杂志

Objective To investigate the effects of chronic pain on spatial learning ability and the expression of neuronal cell adhesion molecules (NCAM) in hippocampus in neonatal rats.Methods Sixty newborn SD rats of both sexes were randomly divided into pain group ( n = 30) and control group ( n= 30). In pain group complete Freund' s adjuvant (CFA) 20 ?l was injected subcutaneously in the plantar surface of left hindpaw on the 2nd day after birth, whereas in control group normal saline 20 ?l was injected instead of CFA. The animals were weighed on the 3rd, 11th and 22nd day after birth. Ten animals in each group were anesthetized with intraperitoneal pentobarbital and killed on the 11th and 22nd day after birth respectively. The brains were immediately removed for determination of NCAM expression in CA3 and dentate gyms of hippocampus using immuno-histochemical staining technique. Morris water maze test was performed starting from the 21st day after birth for 8 consecutive days to assess the spatial learning ability ( n = 10 in each group) .Results The latent period before finding the hidden-plateform was significantly longer on the 1st and 4th day of the test (22nd and 25th day after birth) in pain group than in control group (P