Lower Neuron-specific Enolase Levels Research Articles

Ghrelin for Neuroprotection in Post-Cardiac Arrest Coma: a one-year follow-up of cognitive and psychosocial outcomes.

Effective treatments to improve brain recovery after cardiac arrest are needed. Ghrelin showed efficacy in experimental models and was associated with lower neuron specific enolase levels in the clinical Ghrelin in Coma (GRECO) trial. Here we present cognitive and psychosocial outcomes at one-year follow-up. GRECO was a phase 2 multicenter, double-blind, randomized, placebo-controlled trial in comatose patients after cardiac arrest. The intervention was intravenous acyl-ghrelin 600 μg twice daily or placebo for one week, starting within 12 hours after the arrest. Patients were assessed after one year using cognitive tests and questionnaires measuring participation, health-related quality of life, mood, and caregiver strain. Composite z-scores of the cognitive tests were computed by comparing the scores to those of a norm-population and averaging the tests for memory, attention and executive functioning separately. Groups were compared based on composite z-scores and cutoff scores for psychosocial outcomes. Of the 160 participants originally included, 66 of the 85 participants who survived to one year after OHCA completed the psychosocial and cognitive follow-up. The intervention group scored numerically higher across all cognitive domains compared to the control group, but the differences were not statistically significant (memory median = -.850 vs. -1.385, U = 424.5, p = .587; attention median = -.733 vs. -.717, U = 420.5, p = .548; executive functioning median = -.311 vs. -.369, U = 408.5, p = .323). There were significantly fewer signs of depression in the intervention group, U = 322.5, p = .014. This predefined secondary analysis found that ghrelin treatment was associated with non-significantly but consistently better cognitive outcomes and significantly fewer signs of depression. This is in line with the primary outcomes. Clinicaltrialsregister.eu: EUCTR2018-000005-23-NL.

Preliminary Prognostication for Good Neurological Outcomes in the Early Stage of Post-Cardiac Arrest Care

We investigated prognostic strategies for predicting good outcomes in the early stage of post-cardiac-arrest care using multiple prognostic tests that are available until 24 h after the return of spontaneous circulation (ROSC). A retrospective analysis was conducted on 138 out-of-hospital cardiac-arrest patients who underwent prognostic tests, including the gray–white-matter ratio (GWR-BG), the Glasgow Coma Scale motor (GCS-M) score before sedative administration, and the neuron-specific enolase (NSE) level measured at 24 h after the ROSC. We investigated the prognostic performances of the tests as single predictors and in various combination strategies. Classification and regression-tree analysis were used to provide a reliable model for the risk stratification. Out of all the patients, 55 (44.0%) had good outcomes. The NSE level showed the highest prognostic performance as a single prognostic test and provided improved specificities (>70%) and sensitivities (>98%) when used in combination strategies. Low NSE levels (≤32.1 ng/mL) and high GCS-M (≥4) scores identified good outcomes without misclassification. The overall accuracy for good outcomes was 81.8%. In comatose patients with low NSE levels or high GCS-M scores, the premature withdrawal of life-sustaining therapy should be avoided, thereby complying with the formal prognostication-strategy algorithm after at least 72 h from the ROSC.

Blood-Brain Barrier Biomarkers before and after Kidney Transplantation.

Kidney transplantation (KT) may improve the neurological status of chronic kidney disease (CKD) patients, reflected by the altered levels of circulating BBB-specific biomarkers. This study compares the levels of neuron specific enolase (NSE), brain-derived neurotrophic factor (BDNF), neurofilament light chain (NfL), and circulating plasma extracellular vesicles (EVs) in kidney-failure patients before KT and at a two-year follow up. Using ELISA, NSE, BDNF, and NfL levels were measured in the plasma of 74 living-donor KT patients. Plasma EVs were isolated with ultracentrifugation, and characterized for concentration/size and surface protein expression using flow cytometry from a subset of 25 patients. Lower NSE levels, and higher BDNF and NfL were observed at the two-year follow-up compared to the baseline (p < 0.05). Male patients had significantly higher BDNF levels compared to those of females. BBB biomarkers correlated with the baseline lipid profile and with glucose, vitamin D, and inflammation markers after KT. BBB surrogate marker changes in the microcirculation of early vascular aging phenotype patients with calcification and/or fibrosis were observed only in NSE and BDNF. CD31+ microparticles from endothelial cells expressing inflammatory markers such as CD40 and integrins were significantly reduced after KT. KT may, thus, improve the neurological status of CKD patients, as reflected by changes in BBB-specific biomarkers.

Lower circulating neuron-specific enolase concentrations in adults and adolescents with severe mental illness.

Both neurodegenerative and neurodevelopmental abnormalities have been suggested to be part of the etiopathology of severe mental illness (SMI). Neuron-specific enolase (NSE), mainly located in the neuronal cytoplasm, may indicate the process as it is upregulated after neuronal injury while a switch from non-neuronal enolase to NSE occurs during neuronal maturation. We included 1132 adult patients with SMI [schizophrenia (SZ) or bipolar spectrum disorders], 903 adult healthy controls (HC), 32 adolescent patients with SMI and 67 adolescent HC. Plasma NSE concentrations were measured by enzyme immunoassay. For 842 adults and 85 adolescents, we used total grey matter volume (TGMV) based on T1-weighted magnetic resonance images processed in FreeSurfer v6.0. We explored NSE case-control differences in adults and adolescents separately. To investigate whether putative case-control differences in NSE were TGMV-dependent we controlled for TGMV. We found significantly lower NSE concentrations in both adult (p < 0.001) and adolescent patients with SMI (p = 0.007) compared to HC. The results remained significant after controlling for TGMV. Among adults, both patients with SZ spectrum (p < 0.001) and bipolar spectrum disorders (p = 0.005) had lower NSE than HC. In both patient subgroups, lower NSE levels were associated with increased symptom severity. Among adults (p < 0.001) and adolescents (p = 0.040), females had lower NSE concentrations than males. We found lower NSE concentrations in adult and adolescent patients with SMI compared to HC. The results suggest the lack of progressive neuronal injury, and may reflect abnormal neuronal maturation. This provides further support of a neurodevelopmental rather than a neurodegenerative mechanism in SMI.

Prognostic value of neuron-specific enolase in patients with advanced and metastatic non-neuroendocrine non-small cell lung cancer.

Background: Increased serum neuron-specific enolase (NSE) level was found in a substantial proportion (30–69%) of patients with non-small-cell lung cancer (NSCLC), but little was known about the clinical properties of NSE in NSCLC.Objective: We aimed to assess the level of serum NSE to predict prognosis and treatment response in patients with advanced or metastatic non-neuroendocrine NSCLC.Methods: We retrospectively analyzed 363 patients with advanced and metastatic NSCLC between January 2011 and October 2016. The serum NSE level was measured before initiation of treatment.Results: Patients with high NSE level (≥26.1 ng/ml) showed significantly shorter progression-free survival (PFS) (5.69 vs 8.09 months; P=0.02) and significantly shorter overall survival (OS) than patients with low NSE level (11.41 vs 24.31 months; P=0.01).NSE level was an independent prognostic factor for short PFS (univariate analysis, hazard ratio [HR] = 2.40 (1.71–3.38), P<0.001; multivariate analysis, [HR] = 1.81 (1.28–2.56), P=0.001) and OS (univariate analysis, [HR] = 2.40 (1.71–3.37), P<0.001; multivariate analysis, [HR] = 1.76 (1.24–2.50), P=0.002).Conclusion: The survival of NSCLC patients with high serum NSE level was shorter than that of NSCLC patients with low serum NSE levels. Serum NSE level was a predictor of treatment response and an independent prognostic factor.

Effects of fentanyl for pain control and neuroprotection in very preterm newborns on mechanical ventilation

Objective: This study aimed to evaluate the cerebral protection effect of fentanyl infusion in very preterm infants in the first 72 h of mechanical ventilation.Methods: In this double-blind, randomized, controlled trial, mechanically ventilated newborns (<32 weeks’ gestational age) were randomized to fentanyl (continuous infusion of fentanyl) or placebo (continuous infusion of glucose, controls) in the first 72 h of the mechanical ventilation period. The premature infant pain profile (PIPP), cerebral blood flow velocity, neuron-specific enolase (NSE) concentrations in plasma samples, and cerebral function monitoring (CFM) recordings were evaluated.Results: Twenty-seven infants were allocated to the fentanyl group and 26 to the control group. The fentanyl group had significantly lower PIPP scores than did the control group at 12, 24, 48, and 72 h after the start of infusion (all p < .05). No significant changes in hemodynamic parameters were observed during the observation period using transcranial Doppler flow measurements (p > .05). The fentanyl group had lower NSE levels and higher total CFM scores compared with the control group (both p < .05).Conclusion: In very preterm infants on mechanical ventilation, continuous fentanyl infusion might protect the developing brain by relieving pain during the first 72 h of mechanical ventilation.

Serum neuron-specific enolase levels are upregulated in patients with acute lymphoblastic leukemia and are predictive of prognosis.

We explored the relationship between neuron-specific enolase (NSE) levels and the clinical features of acute lymphoblastic leukemia (ALL). Seventy ALL patients and forty-two healthy controls were enrolled in this study, and their serum NSE levels were measured using an electrochemiluminescence assay. The serum NSE concentration was higher in ALL patients than in healthy controls. In ALL patients, the mean serum NSE level declined after complete remission (CR) but increased with relapse. In addition, the mean serum NSE level was lower in the CR group than in the non-CR group. High NSE levels were associated with poorer progression-free and overall survival than low NSE levels. Serum NSE levels closely correlated with several clinical features, including the immunophenotype, risk stratification and serum lactate dehydrogenase levels. Multivariate analysis revealed that high NSE expression was an independent prognostic factor in adult ALL patients. NSE mRNA levels were also higher in ALL cell lines and bone marrow mononuclear cells from ALL patients than in control cells. These results suggested that NSE could be a clinical prognostic factor and a potential therapeutic target in ALL.

Predictors of death among cardiac arrest patients after therapeutic hypothermia: A non-tertiary care center's initial experience

Introduction and ObjectivesTherapeutic hypothermia (TH) is recommended for patients with return of spontaneous circulation (ROSC) after cardiac arrest (CA). There is still uncertainty about management, target temperature and duration of TH. In the present study we aim to describe the initial experience of a non-tertiary care center with TH after CA and to determine predictors of mortality. MethodsDuring the period 2011-2014, out of 2279 patients hospitalized in the intensive care unit, 82 had a diagnosis of CA with ROSC. We determined predictors of mortality and neurological outcome in comatose patients with ROSC after CA treated by TH. ResultsA total of 15 patients were included, mean age 47.3±14 years, 10 (67.0%) male. CA occurred out-of-hospital (n=11; 73.3%) or in-hospital (n=4; 26.7%), in initial shockable (n=10; 66.7%) or non-shockable (n=5, 33.3%) rhythm. The mean time from CA to ROSC (CA-ROSC) was 44.7±36.5 min. All patients met the 24-hour TH target temperature of 33°C. The mean neuron-specific enolase (NSE) level was 93.7±109.0 μg/l. Seven patients (46.7%) were discharged with good cerebral performance and eight (53.3%) died. Patients who survived had lower median age (p=0.032), shorter CA-ROSC (p=0.048), lower NSE levels (p=0.020) and initial ventricular fibrillation rhythm (p=NS). ConclusionsThe effectiveness of TH appears to be related to younger age, shockable initial rhythm and shorter CA-ROSC time. This results indicates some lines of inquiry that should be developed in appropriate prospective studies. The role of biomarkers as predictors of prognosis is an open question, with NSE potentially playing an important role.

Predictors of death among cardiac arrest patients after therapeutic hypothermia: A non-tertiary care center's initial experience

Introduction and ObjectivesTherapeutic hypothermia (TH) is recommended for patients with return of spontaneous circulation (ROSC) after cardiac arrest (CA). There is still uncertainty about management, target temperature and duration of TH. In the present study we aim to describe the initial experience of a non-tertiary care center with TH after CA and to determine predictors of mortality. MethodsDuring the period 2011-2014, out of 2279 patients hospitalized in the intensive care unit, 82 had a diagnosis of CA with ROSC. We determined predictors of mortality and neurological outcome in comatose patients with ROSC after CA treated by TH. ResultsA total of 15 patients were included, mean age 47.3±14 years, 10 (67.0%) male. CA occurred out-of-hospital (n=11; 73.3%) or in-hospital (n=4; 26.7%), in initial shockable (n=10; 66.7%) or non-shockable (n=5, 33.3%) rhythm. The mean time from CA to ROSC (CA-ROSC) was 44.7±36.5 min. All patients met the 24-hour TH target temperature of 33°C. The mean neuron-specific enolase (NSE) level was 93.7±109.0 μg/l. Seven patients (46.7%) were discharged with good cerebral performance and eight (53.3%) died. Patients who survived had lower median age (p=0.032), shorter CA-ROSC (p=0.048), lower NSE levels (p=0.020) and initial ventricular fibrillation rhythm (p=NS). ConclusionsThe effectiveness of TH appears to be related to younger age, shockable initial rhythm and shorter CA-ROSC time. This results indicates some lines of inquiry that should be developed in appropriate prospective studies. The role of biomarkers as predictors of prognosis is an open question, with NSE potentially playing an important role.

Serum neuron-specific enolase levels were associated with the prognosis of small cell lung cancer: a meta-analysis

This study aims to evaluate the association of serum neuron-specific enolase (NSE) levels with the prognosis of small cell lung cancer (SCLC). Literature retrieval, trials selection and assessment, data collection, and statistical analysis were performed according to the Revman 5.0 guidelines. Literature-based searching was guided to gather data and either fixed-effect or random-effect model was used to pool the hazard ratio (HR) according to the test of heterogeneity. A total of 11 eligible studies that included 3,497 SCLC patients and 3,344 control subjects were analyzed. About 68.6 % of patients had high serum levels of NSE, according to the cutoff value defined by the authors. The HR of high levels of NSE for overall survival (OS) was 1.74 times that of low levels of NSE in SCLC patients (95 % CI, 1.14 to 2.65; P = 0.01). Patients with high levels of NSE appear to have a poorer OS compared with those with low levels of NSE.

Modeling Serum Biomarkers S100 Beta and Neuron-Specific Enolase as Predictors of Outcome After Out-of-Hospital Cardiac Arrest: An Aid to Clinical Decision Making

The aim of this study was to determine the added value of the serum biomarkers S100 and neuron-specific enolase to clinical characteristics for predicting outcome after out-of-hospital cardiac arrest. Serum S100 beta (S100B) and neuron-specific enolase concentrations rise after brain injury. A prolective observational study was conducted among all adult survivors of nontraumatic out-of-hospital cardiac arrest admitted to 1 hospital (April 3, 2008 to April 3, 2011). Three blood samples (on arrival and on days 1 and 3) were drawn for biomarkers, contingent on survival. Follow-up continued until in-hospital death or discharge. Outcomes were defined as good (Cerebral Performance Category score 1 or 2) or poor (Cerebral performance category score 3 to 5). A total of 195 patients were included (65.6% men, mean age 73 ± 16 years), with presenting rhythms of asystole in 61.5% and ventricular tachycardia or ventricular fibrillation in 24.1%. Only 43 patients (22.0%) survived to hospital discharge, 26 (13.3%) with good outcomes. Patients with good outcomes had significantly lower S100B levels at all time points and lower neuron-specific enolase levels on days 1 and 3 compared with those with poor outcomes. Independent predictors at admission of a good outcome were younger age, a presenting rhythm of ventricular tachycardia or ventricular fibrillation, and lower S100B level. Predictors on day 3 were younger age and lower day 3 S100B level. The area under the receiver-operating characteristic curve of the admission-day model was 0.932 with and 0.880 without biomarker data (p = 0.027 for the difference). Risk stratification after out-of-hospital cardiac arrest using both clinical and biomarker data is feasible. The biomarkers, although adding an ostensibly modest 5.2% to the area under the receiver-operating characteristic curve, substantially reduced the level of uncertainty in decision making. Nevertheless, current biomarkers cannot replace societal considerations in determining acceptable levels of uncertainty. (Protein S100 Beta as a Predictor of Resuscitation Outcome; NCT00814814).

Early Biomarkers of Clinical–Diffusion Mismatch in Acute Ischemic Stroke

Clinical-diffusion mismatch (CDM; National Institutes of Health Stroke Scale score≥8 and diffusion-weighted imaging lesion volume<25 mL) has been suggested as a surrogate of ischemic brain at risk of infarction and might be used to recognize salvageable ischemic tissue. Our aim was to identify early biomarkers associated with the presence of CDM. We prospectively evaluated CDM in 226 patients (71.6±11.1 years, 58% men) with hemispheric ischemic stroke within 12 hours from symptom onset (median, 3.6 hours). Diffusion-weighted MRI lesion volume was measured by manual segmentation method. Serum levels of glutamate, aspartate, interleukin-10, tumor necrosis factor-α, interleukin-6, S100β, neuron-specific enolase, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, active matrix metalloproteinase-9, and cellular fibronectin were determined by immunoassay or high-performance liquid chromatography techniques in blood samples obtained at admission. CDM was found in 61 patients (26.9%). Patients with CDM had higher serum levels of interleukin-10, tumor necrosis factor-α, and glutamate and lower serum levels of neuron-specific enolase, interleukin-6, and active matrix metalloproteinase-9 (all P<0.0001). Binary logistic regression showed that tumor necrosis factor-α≥21 pg/mL (OR, 21), glutamate≥230 μmol/L (OR, 27), neuron-specific enolase≥23 ng/mL (OR, 0.05), interleukin-6≥10 pg/mL (OR, 0.06), and active matrix metalloproteinase-9≥21 ng/mL (OR, 0.28) were independent molecular predictors of CDM after adjustment for covariates. The association of interleukin-10≥23 pg/mL and glutamate≥230 μmol/L levels predicted CDM with a sensitivity of 96% and a specificity of 98%. High levels of interleukin-10, tumor necrosis factor-α, and glutamate as well as low levels of neuron-specific enolase, interleukin-6, and active matrix metalloproteinase-9 are associated with CDM.

Neuron-Specific enolase as a marker for acute ischemic stroke: A systematic review

Study objectives: Neuron-specific enolase (NSE) is a glycolytic enzyme that is found mainly in the cytoplasm of neurons and cells of neuroendocrine origin. To date, the majority of the work delineating the usefulness of NSE as a marker for acute ischemic stroke has been inconclusive and on a limited number of patients. We determine whether serum NSE correlates with time of onset of stroke symptoms, volume of infarct, stroke severity, functional outcome, or hospital length of stay. We determine whether serial NSE levels are useful as a marker for ongoing brain ischemia. We determine if NSE levels are significantly higher for patients with stroke compared with controls at various intervals. Methods: All abstracts and published full reports identified as potentially relevant by the literature search were independently assessed for inclusion in the review by each of the reviewers. This was a qualitative analysis. Results: Twelve studies satisfying the entry criteria were identified. Four studies examined time of onset of stroke symptoms versus earliest time NSE levels were detectable. NSE levels were found to be higher ranging from 4 to 8 hours postinfarct. Seven studies found increased NSE levels to be associated with increased size of stroke. Two studies found no correlation. Two studies examined stroke severity versus NSE levels. Higher NSE levels generally indicated worse outcome, but with low NSE levels, the results were equivocal. Seven of the 12 included studies examined functional outcome at discharge and follow-up versus NSE levels. Four of these 7 studies found no correlation between serum NSE and functional outcome. No correlation was found when using the Scandinavian Stroke Scale, Activities of Daily Living Scale, or the Glasgow Outcome Score. There was a correlation with Barthel index, modified Rankin Score at 90 days, admission and day 7 National Institutes of Health Stroke Scale, and a trend with the Lindley score. No trial correlated hospital length of stay with NSE levels without the confounding influence of increased volume of infarct leading to increased length of stay. Three studies found a relationship between NSE levels and time; however, 3 studies did not. Seven studies reported statistically significant differences between NSE levels in patients with stroke compared with control groups. One study reported that patients with total anterior cerebral strokes had statistically elevated levels of NSE compared with controls. However, patients with partial anterior cerebral stroke did not reach statistical significance with regard to NSE levels. Conclusion: Overall, according to the data for these 597 patients, it is possible to state that serum NSE level does in fact seem to be higher in stroke patients compared with controls and does appear to correlate with volume of infarct. However, it does not appear to correlate with functional outcome, and its relationship to stroke severity is unclear.

Cytosolic levels of neuron-specific enolase in squamous cell carcinomas of the lung.

To study the behavior and possible correlations of neuron-specific enolase (NSE) with other clinicobiological parameters, we measured the cytosolic levels of this marker by means of an immunoradiometric assay (IRMA) in 95 squamous cell lung carcinoma samples. We also analyzed the levels of pS2, tissue-type plasminogen activator (t-PA), hyaluronic acid (HA), free beta subunit of human chorionic gonadotropin (beta-HCG), CYFRA 21.1 and CA 125 in cytosol. On the cell surface we analyzed the concentrations of epidermal growth factor receptor (EGFR), HA, erbB-2 oncoprotein, CD44s, CD44v5 and CD44v6. Other parameters considered were clinical stage, lymph node involvement, histological grade (HG), ploidy and the cellular S-phase fraction measured by flow cytometry on nuclei obtained from fresh tissues. In the 95 squamous cell carcinomas the cytosolic levels of NSE varied from 4.5 to 2235 ng/mg protein (median: 267) and were significantly higher (p < 0.001) than those observed in 38 samples of normal pulmonary tissue obtained from the same patients (range: 56-657; median: 141.5). When classifying tumors according to the different parameters analyzed, we observed that the levels of NSE were higher in aneuploid than in diploid cases (p = 0.046) and in those that were HG3 than in those that were HG2 (p < 0.001). Tumors with high NSE levels (> 422 ng/mg protein; 75th percentile) were more likely to have high S-phase values (p = 0.012) and were more frequently aneuploid (p = 0.038) and HG3 (p < 0.001) than those with low levels of NSE (< 180 ng/mg protein; 25th percentile). These results lead us to the following conclusions: 1) the cytosolic concentrations of NSE are significantly higher in squamous cell carcinomas than in healthy pulmonary tissue, and 2) the cytosolic concentrations of NSE are not correlated with clinical stage or nodal involvement. However, in our study higher levels of the enzyme were statistically correlated with aneuploidy, histological grade 3 and S-phase. This may explain its association with poorer outcome and progression, but also the more favorable response of tumors with elevated NSE to chemotherapy, as suggested by other groups.

Cytosolic levels of neuron-specific enolase in squamous cell carcinomas of the lung

To study the behavior and possible correlations of neuron-specific enolase (NSE) with other clinicobiological parameters, we measured the cytosolic levels of this marker by means of an immunoradiometric assay (IRMA) in 95 squamous cell lung carcinoma samples. We also analyzed the levels of pS2, tissue-type plasminogen activator (t-PA), hyaluronic acid (HA), free beta subunit of human chorionic gonadotropin (beta-HCG), CYFRA 21.1 and CA 125 in cytosol. On the cell surface we analyzed the concentrations of epidermal growth factor receptor (EGFR), HA, erbB-2 oncoprotein, CD44s, CD44v5 and CD44v6. Other parameters considered were clinical stage, lymph node involvement, histological grade (HG), ploidy and the cellular S-phase fraction measured by flow cytometry on nuclei obtained from fresh tissues. In the 95 squamous cell carcinomas the cytosolic levels of NSE varied from 4.5 to 2235 ng/mg protein (median: 267) and were significantly higher (p < 0.001) than those observed in 38 samples of normal pulmonary tissue obtained from the same patients (range: 56-657; median: 141.5). When classifying tumors according to the different parameters analyzed, we observed that the levels of NSE were higher in aneuploid than in diploid cases (p = 0.046) and in those that were HG3 than in those that were HG2 (p < 0.001). Tumors with high NSE levels (> 422 ng/mg protein; 75th percentile) were more likely to have high S-phase values (p = 0.012) and were more frequently aneuploid (p = 0.038) and HG3 (p < 0.001) than those with low levels of NSE (< 180 ng/mg protein; 25th percentile). These results lead us to the following conclusions: 1) the cytosolic concentrations of NSE are significantly higher in squamous cell carcinomas than in healthy pulmonary tissue, and 2) the cytosolic concentrations of NSE are not correlated with clinical stage or nodal involvement. However, in our study higher levels of the enzyme were statistically correlated with aneuploidy, histological grade 3 and S-phase. This may explain its association with poorer outcome and progression, but also the more favorable response of tumors with elevated NSE to chemotherapy, as suggested by other groups.

The significance of NSE and CEA as a differentiation marker for the cellular heterogeneity of small cell lung cancer.

Neuron-specific enolase (NSE) and carcinoembryonic antigen (CEA) levels in the culture supernatant of the 65 pulmonary carcinoma cell lines: Small cell lung cancer (SCLC) 18, large cell carcinoma 14, squamous cell carcinoma 14, adenocarcinoma 14 and adenosquamous cell carcinoma 5, were measured by a radioimmunoassay (RIA). The mean value of NSE was 30.8+/-22.4 ng/ml and 9.2+/-8.7 ng/ml in SCLC and non-SCLC, respectively. The mean value of CEA was 15.1+/-20.9 ng/ml and 26.6+/-72.3 ng/ml in SCLC and non-SCLC, respectively. A significant difference in NSE levels was obtained between SCLC cell lines and non-SCLC cell lines. In SCLC cell lines, a significant inverse proportional correlation was observed between NSE and CEA levels. The CEA production tended to be higher in cells with low levels of NSE than in those with high NSE production. With respect to correlation between marker production and growth characteristics of SCLC cells in vitro, significantly higher NSE and lower CEA levels were found in cells growing with floating colony or neurite like characteristics (classic cell type) than those in cells with epithelial or intermediate growth characteristics (variant cell type). A significant positive correlation between NSE levels and the survival periods was found in follow-up studies of 10 patients who underwent surgery with complete resection of the primary tumor. All of 4 long term survivors over 3 years after surgery had significantly high NSE and relatively low CEA producing tumors. The relationship of these markers to clinical status of the patient suggests that an analysis for correlation of NSE and CEA levels in SCLC patients may be useful to discriminate between a pure neuroendocrine SCLC tumor and a mixed small cell/large cell tumor, and in monitoring therapeutic effect and prognosis of each patient.

Validation of an algorithm able to differentiate small-cell lung cancer (SCLC) from non-small-cell lung cancer (NSCLC) patients by means of a tumour marker panel: analysis of the errors

By means of a mathematical score previously generated by discriminant analysis on 90 lung cancer patients, a new and larger group of 261 subjects [209 with non-small-cell lung cancer (NSCLC) and 52 with small-cell lung cancer (SCLC)] was analysed to confirm the ability of the method to distinguish between these two types of cancers. The score, which included the serum neuron-specific enolase (NSE) and CYFRA-21.1 levels, permitted correct classification of 93% of the patients. When the misclassifications were analysed in detail, the most frequent errors were associated with limited disease SCLC with low NSE levels and with advanced NSCLC with high NSE levels. This demonstrates the importance of the marker in correctly categorizing patients.

Phenotypic Diversity in Neuronal Cell Lines Derived from Raphe Nucleus by Retroviral Transduction

Two neuronal cell lines, RN33B and RN46A, were derived from E12 rat medullary raphe neuroepithelial cells by infection with a retrovirus encoding the temperature-sensitive mutant of SV40 large T antigen (T-ag). At permissive temperature (33°C), both cell lines express nuclear T-ag immunoreactivity, low levels of neuron-specific enolase (NSE), and low (NF-L) and medium (NFM), but not high (NF-H), MW neurofilament proteins. Once differentiated, both cell lines cease dividing, take on a neuronal morphology, and express enhanced levels of NSE and all three NF proteins. The complex interaction of variables which mediates the differentiation of these neuronal cell lines is discussed. RN33B and RN46A cells show both similar and different physiological properties, and those features are highlighted to demonstrate the utility of these cell lines in studying neuronal differentiation, both in vitro and in vivo. For example, the expression of NF-L and NF-M in differentiating RN33B and RN46A cells can be potentiated by activation of protein kinase A. RN33B cells are glutamatergic while RN46A cells are serotonergic. 5-HT uptake and synthesis in RN46A cells are differentially regulated, as synthesis is maximal only in differentiated RN46A cells which have been treated with BDNF followed by partial depolarization. 5-HT uptake is seen at similar levels in both undifferentiated and differentiated RN46A cells and is independent of neurotrophin regulation. Following transplantation into the CNS, RN33B cells survive ≥6 months and differentiate according to local environmental signals; RN46A cells survive ≤2 months and do not show similar plasticity in vivo. These data are modeled to provide a conceptual framework as to the generation and differentiation capacity of neuronal cell lines derived by retroviral transduction.

Distinct regulatory pathways control neurofilament expression and neurotransmitter synthesis in immortalized serotonergic neurons

Following infection of dissociated embryonic day 13 rat medullary raphe cells with a retrovirus encoding the temperature-sensitive mutant of SV40 large T-antigen (T-ag), a neuronal cell line, RN46A, was cloned by serial dilution. At 33 degrees C, RN46A cells express nuclear T-ag immunoreactivity and divide with a doubling time of 9 hr. Undifferentiated RN46A cells express low levels of neuron-specific enolase (NSE) and low (NF-L)-and medium (NF-M)- but not high (NF-H)-molecular-weight neurofilament proteins. Under differentiation conditions, RN46A cells cease dividing, take on a neuronal morphology, and express enhanced levels of NSE and all three NF proteins. Elevation of intracellular cAMP levels increases neurofilament protein expression, whereas activators of various other intracellular second messenger systems have no effect. Differentiated RN46A cells express low-affinity nerve growth factor (NGF) receptor (p75NGFR) and are immunoreactive using an antibody that recognizes the carboxy-terminal 13 amino acids of all three trk proteins (pan-trk). Both immunoreactivities could be potentiated by treatment with brain-derived neurotrophic factor (BDNF), NGF, and adrenocorticotropic hormone, fragment 4-10 (ACTH4-10). Differentiated RN46A cells express low levels of tryptophan hydroxylase (TPH) immunoreactivity, which could be enhanced by treatment with ACTH4-10, BDNF, or NGF. Low levels of serotonin immunoreactivity are detected in differentiated RN46A cells, and this was potentiated by differentiating RN46A cells with BDNF for 8 d and 40 mM KCl for days 4-8. HPLC analysis confirmed these immunohistochemical data. RN46A cells should prove useful to elucidate intracellular mechanisms that control neurofilament assembly and 5-HT expression in differentiating raphe neurons.

Characterization of four new cell lines derived from small-cell gastrointestinal carcinoma.

Four human small-cell gastrointestinal carcinoma cell lines were established from tumor tissues of patients with esophageal, gastric or rectal cancer, and were studied morphologically and biochemically in comparison with small-cell lung carcinoma (SCLC) cell lines and common gastric cancer cell lines. Cells from all the small-cell gastrointestinal carcinoma lines were as small as classic SCLC cells and had characteristic neurosecretory granules. Cells from only one line grew as tightly packed spherical aggregates of floating cells, and those of the other 3 grew attached to substrate. Although high levels of creatine kinase brain isoenzyme (CK-BB) were detected in all 4 cell lines, 2 of them showed low levels of aromatic L-amino-acid decarboxylase and 3 had low levels of neuron-specific enolase (NSE). None of the lines showed simultaneous elevation of enzymes. C-myc, N-myc, and L-myc were not amplified in any of the cell lines, but c-myc mRNA was expressed in 2 lines. Our findings indicate that all small-cell gastrointestinal carcinoma cells examined belong to the variant type which is used in the classification of SCLC. Furthermore, the ECC18 line, derived from esophageal cancer, seemed to be of true endocrine cell origin, while the 3 other small-cell gastrointestinal carcinoma lines seemed to arise via neoplastic neometaplasia from adenocarcinoma cells to endocrine cells.