The S100 protein family: history, function, and expression

Chronic stress, hippocampus and parvalbumin-positive interneurons: what do we know so far?

The hippocampus is a brain structure involved in the regulation of hypothalamic-pituitary-adrenal (HPA) axis and stress response. It plays an important role in the formation of declarative, spatial and contextual memory, as well as in the processing of emotional information. As a part of the limbic system, it is a very susceptible structure towards the effects of various stressors. The molecular mechanisms of structural and functional alternations that occur in the hippocampus under chronic stress imply an increased level of circulating glucocorticoids (GCs), which is an HPA axis response to stress. Certain data show that changes induced by chronic stress may be independent from the GCs levels, opening the possibility of existence of other poorly explored mechanisms and pathways through which stressors act. The hippocampal GABAergic parvalbumin-positive (PV+) interneurons represent an especially vulnerable population of neurons in chronic stress, which may be of key importance in the development of mood disorders. However, cellular and molecular hippocampal changes that arise as a consequence of chronic stress still represent a large and unexplored area. This review discusses the current knowledge about the PV+ interneurons of the hippocampus and the influence of chronic stress on this intriguing population of neurons.

Therapeutic effects of various methods of MSC transplantation on cerebral resuscitation following cardiac arrest in rats

In the present study, mesenchymal stem cells (MSCs) were transplanted into the brain of rats following cardiopulmonary resuscitation (CPR) by three different methods: Direct stereotaxic injection into the lateral cerebral ventricle (LV), intra-carotid administration (A), and femoral venous infusion (V). The three different methods were compared by observing the effects of MSCs on neurological function following global cerebral hypoxia-ischemia, in order to determine the optimum method for MSC transplantation. MSCs were transplanted in groups A, V and LV following the restoration of spontaneous circulation. Neurological deficit scale scores were higher in the transplantation groups, as compared with the control group. Neuronal damage, brain water content and serum levels of S100 calcium-binding protein B were reduced in the hippo-campus and temporal cortex of the transplantation groups, as compared with the control rats following resuscitation. MSCs were able to migrate inside the brain tissue following transplantation, and were predominantly distributed in the hippocampus and temporal cortex where the neurons were vulnerable during global cerebral ischemia. These results suggest that transplantation of MSCs may notably improve neurological function following CPR in a rat model. Of the three different methods of MSC transplantation tested in the present study, LV induced the highest concentration of MSCs in brain areas vulnerable to global cerebral ischemia, and therefore, produced the best neurological outcome.

Immunohistochemical markers of neural progenitor cells in the early embryonic human cerebral cortex

The development of the human central nervous system represents a delicate moment of embryogenesis. The purpose of this study was to analyze the expression of multiple immunohistochemical markers in the stem/progenitor cells in the human cerebral cortex during the early phases of development. To this end, samples from cerebral cortex were obtained from 4 human embryos of 11 weeks of gestation. Each sample was formalin-fixed, paraffin embedded and immunostained with several markers including GFAP, WT1, Nestin, Vimentin, CD117, S100B, Sox2, PAX2, PAX5, Tβ4, Neurofilament, CD44, CD133, Synaptophysin and Cyclin D1. Our study shows the ability of the different immunohistochemical markers to evidence different zones of the developing human cerebral cortex, allowing the identification of the multiple stages of differentiation of neuronal and glial precursors. Three important markers of radial glial cells are evidenced in this early gestational age: Vimentin, Nestin and WT1. Sox2 was expressed by the stem/progenitor cells of the ventricular zone, whereas the postmitotic neurons of the cortical plate were immunostained by PAX2 and NSE. Future studies are needed to test other important stem/progenitor cells markers and to better analyze differences in the immunohistochemical expression of these markers during gestation.

Role of Systems Biology in Brain Injury Biomarker Discovery: Neuroproteomics Application

Years of research in the field of neurotrauma have led to the concept of applying systems biology as a tool for biomarker discovery in traumatic brain injury (TBI). Biomarkers may lead to understanding mechanisms of injury and recovery in TBI and can be potential targets for wound healing, recovery, and increased survival with enhanced quality of life. The literature available on neurotrauma studies from both animal and clinical studies has provided rich insight on the molecular pathways and complex networks of TBI, elucidating the proteomics of this disease for the discovery of biomarkers. With such a plethora of information available, the data from the studies require databases with tools to analyze and infer new patterns and associations. The role of different systems biology tools and their use in biomarker discovery in TBI are discussed in this chapter.

In Children and Youth with Mild and Moderate Traumatic Brain Injury, Glial Fibrillary Acidic Protein Out-Performs S100β in Detecting Traumatic Intracranial Lesions on Computed Tomography

In adults, glial fibrillary acidic protein (GFAP) has been shown to out-perform S100β in detecting intracranial lesions on computed tomography (CT) in mild traumatic brain injury (TBI). This study examined the ability of GFAP and S100β to detect intracranial lesions on CT in children and youth involved in trauma. This prospective cohort study enrolled a convenience sample of children and youth at two pediatric and one adult Level 1 trauma centers following trauma, including both those with and without head trauma. Serum samples were obtained within 6 h of injury. The primary outcome was the presence of traumatic intracranial lesions on CT scan. There were 155 pediatric trauma patients enrolled, 114 (74%) had head trauma and 41 (26%) had no head trauma. Out of the 92 patients who had a head CT, eight (9%) had intracranial lesions. The area under the receiver operating characteristic curve (AUC) for distinguishing head trauma from no head trauma for GFAP was 0.84 (0.77-0.91) and for S100β was 0.64 (0.55-0.74; p<0.001). Similarly, the AUC for predicting intracranial lesions on CT for GFAP was 0.85 (0.72-0.98) versus 0.67 (0.50-0.85) for S100β (p=0.013). Additionally, we assessed the performance of GFAP and S100β in predicting intracranial lesions in children ages 10 years or younger and found the AUC for GFAP was 0.96 (95% confidence interval [CI] 0.86-1.00) and for S100β was 0.72 (0.36-1.00). In children younger than 5 years old, the AUC for GFAP was 1.00 (95% CI 0.99-1.00) and for S100β 0.62 (0.15-1.00). In this population with mild TBI, GFAP out-performed S100β in detecting head trauma and predicting intracranial lesions on head CT. This study is among the first published to date to prospectively compare these two biomarkers in children and youth with mild TBI.

Urinary Nucleic Acid TSPAN13-to-S100A9 Ratio as a Diagnostic Marker in Prostate Cancer

The potential use of urinary nucleic acids as diagnostic markers in prostate cancer (PCa) was evaluated. Ninety-five urine samples and 234 prostate tissue samples from patients with PCa and benign prostatic hyperplasia (BPH) were analyzed. Micro-array analysis was used to identify candidate genes, which were verified by the two-gene expression ratio and validated in tissue mRNA and urinary nucleic acid cohorts. Real-time quantitative polymerase chain reaction (qPCR) was used to measure urinary nucleic acid levels and tissue mRNA expression. The TSPAN13-to-S100A9 ratio was selected to determine the diagnostic value of urinary nucleic acids in PCa (P = 0.037) and shown to be significantly higher in PCa than in BPH in the mRNA and nucleic acid cohort analyses (P < 0.001 and P = 0.013, respectively). Receiver operating characteristic (ROC) analysis showed that the area under the ROC curve was 0.898 and 0.676 in tissue mRNA cohort and urinary nucleic acid cohort, respectively. The TSPAN13-to-S100A9 ratio showed a strong potential as a diagnostic marker for PCa. The present results suggest that the analysis of urine supernatant can be used as a simple diagnostic method for PCa that can be adapted to the clinical setting in the future.

Overexpression of S100A14 in human serous ovarian carcinoma

S100 calcium binding protein A14 (S100A14) is a member of the S100 protein family that plays an important role in the progression of several types of cancer. In the present study, the expression and clinical effect of S100A14 was evaluated in serous ovarian carcinoma (SOC). SOC tissue specimens and a panel of normal ovarian and fallopian tubal tissue specimens were obtained between November 2008 and August 2012 from the Affiliated Hospital of Qingdao University. Immunohistochemistry (IHC) was used to detect the expression of S100A14 in the SOC and normal control tissues. In addition, ELISA was performed to assess S100A14 expression in a subset of serum samples. The association between the expression of S100A14 in SOC and the corresponding clinical and pathological data was analyzed. The IHC results revealed that S100A14 was mainly located in the cytoplasm of the majority of SOC cells, and the expression levels of S100A14 in the tumor tissues were significantly increased compared with the levels identified in normal ovarian specimens (P<0.001). Consistently, the serum levels of S100A14 in patients with SOC were also increased compared with the levels in healthy individuals (P<0.001). S100A14 expression was similar in the epithelium of SOC lesions and the fallopian tube, which supported the dualistic model for ovarian serous carcinogenesis. Additional analysis of the expression of S100A14 and corresponding clinical and pathological data revealed the correlation between the elevated expression of S100A14 and resistance to platinum-based chemotherapy. However, the protein level of S100A14 was not associated with the pathological stage, differentiation or metastasis of SOC. Overall, the present results demonstrate that S100A14 is likely to be involved in the resistance of SOC to platinum-based chemotherapy.

S100B inhibition reduces behavioral and pathologic changes in experimental traumatic brain injury

Neuroinflammation following traumatic brain injury (TBI) is increasingly recognized to contribute to chronic tissue loss and neurologic dysfunction. Circulating levels of S100B increase after TBI and have been used as a biomarker. S100B is produced by activated astrocytes and can promote microglial activation; signaling by S100B through interaction with the multiligand advanced glycation end product-specific receptor (AGER) has been implicated in brain injury and microglial activation during chronic neurodegeneration. We examined the effects of S100B inhibition in a controlled cortical impact model, using S100B knockout mice or administration of neutralizing S100B antibody. Both interventions significantly reduced TBI-induced lesion volume, improved retention memory function, and attenuated microglial activation. The neutralizing antibody also significantly reduced sensorimotor deficits and improved neuronal survival in the cortex. However, S100B did not alter microglial activation in BV2 cells or primary microglial cultures stimulated by lipopolysaccharide or interferon gamma. Further, proximity ligation assays did not support direct interaction in the brain between S100B and AGER following TBI. Future studies are needed to elucidate specific pathways underlying S100B-mediated neuroinflammatory actions after TBI. Our results strongly implicate S100B in TBI-induced neuroinflammation, cell loss, and neurologic dysfunction, thereby indicating that it is a potential therapeutic target for TBI.

Glial Fibrillary Acidic Protein and Ubiquitin C-Terminal Hydrolase-L1 as Outcome Predictors in Traumatic Brain Injury

OBJECTIVE

Biomarkers ubiquitin C-terminal hydrolase-L1 (UCH-L1) and glial fibrillary acidic protein (GFAP) may help detect brain injury, assess its severity, and improve outcome prediction. This study aimed to evaluate the prognostic value of these biomarkers during the first days after brain injury.

METHODS

Serum UCH-L1 and GFAP were measured in 324 patients with traumatic brain injury (TBI) enrolled in a prospective study. The outcome was assessed using the Glasgow Outcome Scale (GOS) or the extended version, Glasgow Outcome Scale-Extended (GOSE).

RESULTS

Patients with full recovery had lower UCH-L1 concentrations on the second day and patients with favorable outcome had lower UCH-L1 concentrations during the first 2 days compared with patients with incomplete recovery and unfavorable outcome. Patients with full recovery and favorable outcome had significantly lower GFAP concentrations in the first 2 days than patients with incomplete recovery or unfavorable outcome. There was a strong negative correlation between outcome and UCH-L1 in the first 3 days and GFAP levels in the first 2 days. On arrival, both UCH-L1 and GFAP distinguished patients with GOS score 1-3 from patients with GOS score 4-5, but not patients with GOSE score 8 from patients with GOSE score 1-7. For UCH-L1 and GFAP to predict unfavorable outcome (GOS score ≤ 3), the area under the receiver operating characteristic curve was 0.727, and 0.723, respectively. Neither UCHL-1 nor GFAP was independently able to predict the outcome when age, worst Glasgow Coma Scale score, pupil reactivity, Injury Severity Score, and Marshall score were added into the multivariate logistic regression model.

CONCLUSIONS

GFAP and UCH-L1 are significantly associated with outcome, but they do not add predictive power to commonly used prognostic variables in a population of patients with TBI of varying severities.

Neuron-Specific Enolase, S100 Calcium-Binding Protein B, and Heat Shock Protein 70 Levels in Patients With Intracranial Hemorrhage

The authors evaluated neuron-specific enolase (NSE), S100 calcium-binding protein B (S100B), and heat shock protein 70 (HSP 70) levels and their relationships with in-hospital mortality, Glasgow Coma Scale (GCS) scores, and National Institute of Health Stroke Scale (NIHSS) scores. In total, 35 patients older than 18 years were presented to our emergency department and were diagnosed with non-traumatic intracranial hemorrhage (ICH) and 32 healthy controls were included. Blood samples were drawn on days 0 and 5. S100 calcium-binding protein B and HSP levels were significantly higher in patients than in controls on days 0 and 5. Neuron-specific enolase levels were higher in patients than in controls on day 0, but there was no significant difference on day 5. S100 calcium-binding protein B was negatively correlated with GCS, whereas it was positively correlated with NIHSS and bleeding volume. There was also a negative correlation between NSE and GCS, but it was not statistically significant. In addition, no significant correlation was found in terms of bleeding volume or NIHSS. Heat shock protein 70 was negatively correlated with GCS and positively correlated with bleeding volume and NIHSS, but these results were not statistically significant. S100 calcium-binding protein B and HSP 70 levels were significantly higher in those who died compared with survivors. The areas under the curve of S100 B, NSE, and HSP 70 for mortality were 0.635, 0.477, and 0.770, respectively. Neuron-specific enolase, S100B, and HSP 70 levels are simple, inexpensive, and objective measures in cases of ICH. These tests can be used to support an assessment for screening ICH patients with clinical scoring systems, such as GCS and NIHSS.

Geometrical versus Random β-TCP Scaffolds: Exploring the Effects on Schwann Cell Growth and Behavior

Numerous studies have demonstrated that Schwann cells (SCs) play a role in nerve regeneration; however, their role in innervating a bioceramic scaffold for potential application in bone regeneration is still unknown. Here we report the cell growth and functional behavior of SCs on β-tricalcium phosphate (β-TCP) scaffolds arranged in 3D printed-lattice (P-β-TCP) and randomly-porous, template-casted (N-β-TCP) structures. Our results indicate that SCs proliferated well and expressed the phenotypic markers p75^LNGFR and the S100-β subunit of SCs as well as displayed growth morphology on both scaffolds, but SCs showed spindle-shaped morphology with a significant degree of SCs alignment on the P-β-TCP scaffolds, seen to a lesser degree in the N-β-TCP scaffold. The gene expressions of nerve growth factor (β-ngf), neutrophin–3 (nt–3), platelet-derived growth factor (pdgf-bb), and vascular endothelial growth factor (vegf-a) were higher at day 7 than at day 14. While no significant differences in protein secretion were measured between these last two time points, the scaffolds promoted the protein secretion at day 3 compared to that on the cell culture plates. These results together imply that the β-TCP scaffolds can support SC cell growth and that the 3D-printed scaffold appeared to significantly promote the alignment of SCs along the struts. Further studies are needed to investigate the early and late stage relationship between gene expression and protein secretion of SCs on the scaffolds with refined characteristics, thus better exploring the potential of SCs to support vascularization and innervation in synthetic bone grafts.

S100B Serum Levels Predict Treatment Response in Patients with Melancholic Depression

BACKGROUND

There is an ongoing search for biomarkers in psychiatry, for example, as diagnostic tools or predictors of treatment response. The neurotrophic factor S100 calcium binding protein B (S100B) has been discussed as a possible predictor of antidepressant response in patients with major depression, but also as a possible biomarker of an acute depressive state. The aim of the present study was to study the association of serum S100B levels with antidepressant treatment response and depression severity in melancholically depressed inpatients.

METHODS

After a wash-out period of 1 week, 40 inpatients with melancholic depression were treated with either venlafaxine or imipramine. S100B levels and Hamilton Depression Rating Scale (HAM-D) scores were assessed at baseline, after 7 weeks of treatment, and after 6 months.

RESULTS

Patients with high S100B levels at baseline showed a markedly better treatment response defined as relative reduction in HAM-D scores than those with low baseline S100B levels after 7 weeks (P=.002) and 6 months (P=.003). In linear regression models, S100B was a significant predictor for treatment response at both time points. It is of interest to note that nonresponders were detected with a predictive value of 85% and a false negative rate of 7.5%. S100B levels were not associated with depression severity and did not change with clinical improvement.

CONCLUSIONS

Low S100B levels predict nonresponse to venlafaxine and imipramine with high precision. Future studies have to show which treatments are effective in patients with low levels of S100B so that this biomarker will help to reduce patients' burden of nonresponding to frequently used antidepressants.

[Release-active antibodies to S100 protein are able to improve the experimental allergic encephalomyelitis]

AIM

To reveal the effects of release-active antibodies to S100 protein in an animal model of multiple sclerosis.

MATERIAL AND METHODS

Sixty female Wistar rats, aged 12 weeks, were included in the study. The pathology was induced by subcutaneous injection of the spinal cord homogenate. Afterwards the rats received a water solution of release-active antibodies to S100 protein (2,5 ml/kg/day, tenoten) or distilled water intragastrically during 30 days. Intramuscular injections of glatiramer acetate (4 mg/kg/day, copaxone) were used as a positive control.

RESULTS AND CONCLUSION

Release-active antibodies to S100 protein enhanced the latency period of the disease, reduced its peak intensity and compensated the loss of body weight of the animals. The experimental drug effect was similar to the results of copaxone injections.

Analysis of S100 calcium binding protein B serum levels in different types of traumatic intracranial lesions

The objective of this study was to determine whether the type of intracranial traumatic lesions, the number of simultaneous traumatic lesions, and the occurrence of skull and facial bone fractures have an influence on S100 calcium binding protein B (S100B) serum levels. Patients with blunt traumatic brain injury were prospectively enrolled into this cohort study over a period of 13 months. Venous blood samples were obtained prior to emergency cranial CT scan in all patients within 3 h after injury. The patients were then assigned into six groups: 1) concussion, 2) epidural hematoma, 3) subdural hematoma, 4) subarachnoid hemorrhage, 5) brain contusions, and 6) brain edema. The study included 1696 head trauma patients with a mean age of 57.7 ± 25.3 years, and 126 patients (8%) had 182 traumatic lesions on CT. Significant differences in S100B serum levels were found between cerebral edema and the other four bleeding groups: epidural p = 0.0002, subdural p < 0.0001, subarachnoid p = 0.0001, brain contusions p = 0.0003, and concussion p < 0.0001. Significant differences in S100B values between patients with one or two intracranial lesions (p = 0.014) or with three (p < 0.0001) simultaneous intracranial lesions were found. In patients with intracranial traumatic lesions, skull fractures, as well as skull and facial bone fractures occurring together, were identified as significant additional factors for the increase in serum S100B levels (p < 0.0001). Older age was also associated with elevated S100B serum levels (p < 0.0001). Our data show that peak S100B serum levels were found in patients with cerebral edema and brain contusions.

NERVE ENDINGS AND VASCULAR SUPPLY IN SEMITENDINOSUS TENDON OF CEREBRAL PALSY CHILDREN

Objective: To evaluate the distribution of SP (substance P) and S-100 peptide immunoreactivity, as well as the vascular supply of tissues commonly used as grafts for anterior cruciate ligament (ACL) reconstruction. A second aim was to compare the above mentioned distribution in the semitendinosus muscle tendons of cerebral palsy (CP) patients with the semitendinosus muscle tendons and patellar tendons of patients without CP. Methods: The first group consisted of 14 children with cerebral palsy with a mean age of 11.7 years old. At the time of hamstring lengthening operation, a sample of semitendinosus muscle was taken for analysis. The second group comprised 20 patients treated for isolated ACL rupture of the knee (mean age 32 years old). Group three comprised ten patients in the mean age of 14.3 years old treated for recurrent lateral patellar dislocation, and from whom a sample of patellar tendon was obtained. Results: No statistically significant differences were demonstrated with regard to the amount of immunopositive nerve fibers expressing SP or S-100 in all 3 groups of patients. A significant difference was noted in the number of blood vessels between the adult and child semitendinosus muscles, but not between the semitendinosus muscles and patellar tendon of children. Conclusion: The number of nociceptors as well as proprioceptive fibers is similar in patients with CP and patients from a neurologically healthy population. Level of Evidence IV, Cases Series.

A Role of Serum-Based Neuronal and Glial Markers as Potential Predictors for Distinguishing Severity and Related Outcomes in Traumatic Brain Injury

Objective

Optimal treatment decision and estimation of the prognosis in traumatic brain injury (TBI) is currently based on demographic and clinical predictors. But sometimes, there are limitations in these factors. In this study, we analyzed three central nervous system biomarkers in TBI patients, will discuss the roles and clinical applications of biomarkers in TBI.

Methods

From July on 2013 to August on 2014, a total of 45 patients were included. The serum was obtained at the time of hospital admission, and biomarkers were extracted with centrifugal process. It was analyzed for the level of S-100 beta (S100B), glial fibrillary acidic protein (GFAP), and ubiquitin carboxy-terminal hydrolase-L1 (UCH-L1).

Results

This study included 33 males and 12 females with a mean age of 58.5 (19-84) years. TBI patients were classified into two groups. Group A was severe TBI with Glasgow Coma Scale (GCS) score 3-5 and Group B was mild TBI with GCS score 13-15. The median serum concentration of S100B, GFAP, and UCH-L1 in severe TBI were raised 5.1 fold, 5.5 fold, and 439.1 fold compared to mild injury, respectively. The serum levels of these markers correlated significantly with the injury severity and clinical outcome (p<0.001). Increased level of markers was strongly predicted poor outcomes.

Conclusion

S100B, GFAP, and UCH-L1 serum level of were significantly increased in TBI according to severity and associated clinical outcomes. Biomarkers have potential utility as diagnostic, prognostic, and therapeutic adjuncts in the setting of TBI.

Conditioning solid tumor microenvironment through inflammatory chemokines and S100 family proteins

Recently, there has been growing attention to the role of the tumor microenvironment (TME) in cancer growth, metastasis and emergence of chemotherapy resistance. Stromal and tumor cells make up the TME and interact with each other through a complex cross-talk manner. This interaction is facilitated by a variety of growth factors, cytokines, chemokines and S100 proteins. In this review, we focus on chemokines and their cognate receptors in regulating the tumorigenic process. Chemokines are cytokines that have chemotactic potential. Chemokine receptors are expressed on tumor cells and stromal cells. Chemokines and their cognate receptors modulate tumor growth and metastasis in a paracrine and autocrine manner. They play a major role in the modulation of stromal cell recruitment, angiogenic potential, cancer cell proliferation, survival, adhesion, invasion and metastasis to distant sites. In addition, a new class of calcium binding family S100 proteins has been getting attention as they play significant roles in tumor progression and metastasis by modulating TME. Here, we highlight recent developments regarding the inflammatory chemokine/S100 protein systems in the TME. We also focus on how chemokines/S100 proteins, through their role in the TME, modulate cancer cell ability to grow, proliferate, invade and metastasize to different organs. This review highlights the possibility of using the chemokine/chemokine receptor axis as a promising strategy in cancer therapy, the current difficulties in achieving this goal, and how it could be overcome for successful future therapeutic intervention.

Diagnostic performance of S100B protein serum measurement in detecting intracranial injury in children with mild head trauma

OBJECTIVE

To assess the accuracy of S100B serum level to detect intracranial injury in children with mild traumatic brain injury.

METHODS

A multicenter prospective cohort study was carried out in the paediatric emergency departments of three tertiary hospitals in Switzerland between January 2009 and December 2011. Participants included children aged <16 years with a mild traumatic brain injury (GCS ≥13) for whom a head CT was requested by the attending physician. Venous blood was obtained within 6 h of the trauma in all children for S100B measurement before a head CT was performed. As the S100B value was not available during the acute care period, the patient's management was not altered. The main measures were protein S100B value and the CT result.

RESULTS

20/73 (27.4%) included children had an intracranial injury detected on CT. S100B receiver operating characteristics area under the curve was 0.73 (95% CI 0.60 to 0.86). With a 0.14 µg/L cut-off point, S100B reached an excellent sensitivity of 95% (95% CI 77% to 100%) and 100% (95% CI 81% to 100%) in all children and in children aged >2 years, respectively. The specificity, however, was 34% (95% CI 27% to 36%) and 37% (95% CI 30% to 37%), respectively.

CONCLUSIONS

S100B has an excellent sensitivity but poor specificity. It is therefore an accurate tool to help rule out an intracranial injury but cannot be used as the sole marker owing to its specificity. Used with clinical decision rules, S100B may help to reduce the number of unnecessary CT scans.

Role of T cell-glial cell interactions in creating and amplifying central nervous system inflammation and multiple sclerosis disease symptoms

Multiple Sclerosis (MS) is an inflammatory disease of the Central Nervous System (CNS) that causes the demyelination of nerve cells and destroys oligodendrocytes, neurons and axons. Historically, MS has been thought of as a T cell-mediated autoimmune disease of CNS white matter. However, recent studies have identified gray matter lesions in MS patients, suggesting that CNS antigens other than myelin proteins may be involved during the MS disease process. We have recently found that T cells targeting astrocyte-specific antigens can drive unique aspects of inflammatory CNS autoimmunity, including the targeting of gray matter and white matter of the brain and inducing heterogeneous clinical disease courses. In addition to being a target of T cells, astrocytes play a critical role in propagating the inflammatory response within the CNS induced NF-κB signaling. Here, we will discuss the pathophysiology of CNS inflammation mediated by T cell—glial cell interactions and its contributions to CNS autoimmunity.

S100B Up-Regulates Macrophage Production of IL1β and CCL22 and Influences Severity of Retinal Inflammation

S100B is a Ca2+ binding protein and is typically associated with brain and CNS disorders. However, the role of S100B in an inflammatory situation is not clear. The aim of the study was to determine whether S100B is likely to influence inflammation through its effect on macrophages. A murine macrophage cell line (RAW 264.7) and primary bone marrow derived macrophages were used for in vitro studies and a model of retinal inflammatory disease in which pathogenesis is highly dependent on macrophage infiltration, Experimental Autoimmune Uveoretinitis, for in vitro study. Experimental Autoimmune Uveoretinitis is a model for the human disease posterior endogenous uveoretinitis, a potentially blinding condition, with an autoimmune aetiology, that mainly affects the working age group. To date the involvement of S100B in autoimmune uveoretinitis has not been investigated. Real-time PCR array analysis on RAW 246.7 cells indicated up-regulation of gene expression for various cytokines/chemokines in response to S100B, IL-1β and CCL22 in particular and this was confirmed by real-time PCR. In addition flow cytometry and ELISA confirmed up-regulation of protein production in response to S100B for pro-IL-1β and CCL22 respectively. This was the case for both RAW 264.7 cells and bone marrow derived macrophages. Induction of EAU with retinal antigen in mice in which S100B had been deleted resulted in a significantly reduced level of disease compared to wild-type mice, as determined by topical endoscopic fundus imaging and histology grading. Macrophage infiltration was also significantly reduced in S100B deleted mice. Real-time PCR analysis indicated that this was associated with reduction in CCL22 and IL-1β in retinas from S100B knock-out mice. In conclusion S100B augments the inflammatory response in uveoretinitis and this is likely to be, at least in part, via a direct effect on macrophages.

A systematic review of the biomarker S100B: implications for sport-related concussion management

OBJECTIVE

Elevated levels of the astroglial protein S100B have been shown to predict sport-related concussion. However, S100B levels within an athlete can vary depending on the type of physical activity (PA) engaged in and the methodologic approach used to measure them. Thus, appropriate reference values in the diagnosis of concussed athletes remain undefined. The purpose of our systematic literature review was to provide an overview of the current literature examining S100B measurement in the context of PA. The overall goal is to improve the use of the biomarker S100B in the context of sport-related concussion management.

DATA SOURCES

PubMed, SciVerse Scopus, SPORTDiscus, CINAHL, and Cochrane.

STUDY SELECTION

We selected articles that contained (1) research studies focusing exclusively on humans in which (2) either PA was used as an intervention or the test participants or athletes were involved in PA and (3) S100B was measured as a dependent variable.

DATA EXTRACTION

We identified 24 articles. Study variations included the mode of PA used as an intervention, sample types, sample-processing procedures, and analytic techniques.

DATA SYNTHESIS

Given the nonuniformity of the analytical methods used and the data samples collected, as well as differences in the types of PA investigated, we were not able to determine a single consistent reference value of S100B in the context of PA. Thus, a clear distinction between a concussed athlete and a healthy athlete based solely on the existing S100B cutoff value of 0.1 μg/L remains unclear. However, because of its high sensitivity and excellent negative predictive value, S100B measurement seems to have the potential to be a diagnostic adjunct for concussion in sports settings. We recommend that the interpretation of S100B values be based on congruent study designs to ensure measurement reliability and validity.

Hemin protects against hippocampal damage following orthotopic autologous liver transplantation in adult rats

AIMS

Induction of heme oxygenase-1 (HO-1) has been widely accepted to be neuro-protective. This study aimed to examine whether hemin (a HO-1 inducer) attenuates neuronal damage in the hippocampus induced by orthotopic autologous liver transplantation (OALT) in adult rats.

MAIN METHODS

Rats were randomly allocated into four groups (n=8 each): (i) Sham control group; (ii) OALT model group; (iii) Hemin+OALT group, with intra-peritoneal (i.p.) injection of hemin (5 mg/kg) 24 hours (h) before the OALT; and (iv) ZnPP (a HO-1 inhibitor)+OALT group, with i.p. injection of ZnPP (32 mg/kg) 24h before the OALT. Twenty four hours after the surgery, the hippocampal tissues were collected for electron microscopic examination and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) analysis. The levels of hippocampal HO-1 protein and serum S-100β, the concentrations of regional tumor necrosis factor-α (TNF-α) and interleukins (IL-6, IL-10), as well as the status of malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) in the hippocampus were assessed.

KEY FINDINGS

Rats suffered severe neuronal damage in the hippocampus after OALT, mainly in apoptosis. Pre-treatment with hemin obviously alleviated the damage; up-regulated the HO-1 protein level; inhibited the release of TNF-α, IL-6 and MDA; and promoted the activities of SOD, CAT and IL-10; however, pre-treatment with ZnPP did not exhibit the opposite effect, except that a marked increase in serum S-100β level was detected.

SIGNIFICANCE

Hemin up-regulated the expression of HO-1 and attenuated hippocampal neuronal damage induced by OALT.

High spatial resolution imaging mass spectrometry of human optic nerve lipids and proteins

The human optic nerve carries signals from the retina to the visual cortex of the brain. Each optic nerve is comprised of approximately one million nerve fibers that are organized into bundles of 800-1200 fibers surrounded by connective tissue and supportive glial cells. Damage to the optic nerve contributes to a number of blinding diseases including: glaucoma, neuromyelitis optica, optic neuritis, and neurofibromatosis; however, the molecular mechanisms of optic nerve damage and death are incompletely understood. Herein we present high spatial resolution MALDI imaging mass spectrometry (IMS) analysis of lipids and proteins to define the molecular anatomy of the human optic nerve. The localization of a number of lipids was observed in discrete anatomical regions corresponding to myelinated and unmyelinated nerve regions as well as to supporting connective tissue, glial cells, and blood vessels. A protein fragment from vimentin, a known intermediate filament marker for astrocytes, was observed surrounding nerved fiber bundles in the lamina cribrosa region. S100B was also found in supporting glial cell regions in the prelaminar region, and the hemoglobin alpha subunit was observed in blood vessel areas. The molecular anatomy of the optic nerve defined by MALDI IMS provides a firm foundation to study biochemical changes in blinding human diseases.

Specific marker expression and cell state of Schwann cells during culture in vitro

Schwann cells (SCs) in animals exist in different developmental stages or wound repair phases, distinguished mainly by the expression of SC-specific markers. No study has yet determined SC state under in vitro culture conditions, and the specific markers expressed in SC are obscure as well. In this study, we harvested sciatic nerves from newborn mice and isolated SCs by an enzyme-digestion method, then we examined the expression profiles of ten markers (S100, p75^NTR, Sox10, Sox2, GAP43, NCAM, Krox20, Oct6, MBP, and MPZ) at both the RNA and protein levels in in vitro mouse SCs and speculated their relation with in vivo SC stages. We assayed RNA and protein levels of SC specific markers by immunofluorescence, Western Blot, and real-time quantitative RT-PCR. The results show that the expression of most markers (S100, p75^NTR, GAP43, NCAM, Krox20, Oct6, MBP and MPZ) was not detectable in all of early stage cultured SCs. The expression of transcription factors Sox10 and Sox2 was, however, detectable in all SCs. After 8 days, the positive expression rate of all markers except GAP43 and Oct6 was almost 100%.These results indicates Sox10 is a necessary marker for SC identification, while S100 is not reliable. SCs cultured in vitro express Sox2, P75^NTR, NCAM, GAP43, Oct6, and MPZ, suggesting that they are similar to in vivo undifferentiated iSCs or dedifferentiated iSCs after nerve injury.

Downregulation of 425G>a variant of calcium-binding protein S100A14 associated with poor differentiation and prognosis in gastric cancer

PURPOSE

Altered level of S100 calcium-binding proteins is involved in tumor development and progression. However, their role in gastric cancer (GC) is not well documented. We investigated the expression pattern of S100 proteins and differentiation or prognosis as well as possible mechanisms in GC.

METHODS

RT-PCR, Western blot analysis, and immunohistochemistry were used to determine the mRNA and protein expression of S100 family genes in GC. The polymorphisms of promoter and 5'-UTR of S100A14 gene were identified and related to luciferase reporter gene activity. Association of S100A14 expression with clinicopathologic features and survival in GC was analyzed.

RESULTS

We detected upregulated S100A2, S100A6, S100A10, and S100A11 expression and downregulated S100P and S100B expression in GC. Particularly, we detected differential mRNA and protein expression of S100A14 in GC cell lines and primary tumors. Furthermore, S100A14 expression change was related to a differentiated GC phenotype, with an expression in 31/40 (77.5 %) samples of well-differentiated tumors and 29/85 (34.1 %) samples of poorly differentiated tumors (P < 0.001). Moreover, 5-year survival was better in GC cases with positive than negative S100A14 level (P = 0.02). The genetic variant 425G>A on the 5'-UTR of S100A14 was associated with reduced S100A14 expression in GC cells.

CONCLUSION

Decreased expression of S100A14 with presence of its genetic variant 425G>A may be associated with an undifferentiated phenotype and poor prognosis in GC.

Glial pathology in bipolar disorder: potential therapeutic implications

Bipolar disorder (BD) is a chronic and severe mental disorder with recurrent episodes of mania and depression. In addition to neuronal alterations, accumulating evidences have revealed the importance of glial system in pathophysiology and phenotype of the illness. Postmortem studies have repeatedly demonstrated the alterations in glial cells and its functions in patients with BD. The activated microglia and inflammatory cytokines are proposed to be the potential biomarkers that may help to predict disease exacerbation in BD. On the other hand, anti-BD drugs have been shown to produce profound effects on glial activity, which not only contributes to the therapeutic efficacy, but may also provide a potential target for the drug development of BD. We will focus on the recent development of glial abnormalities and potential therapeutic benefits targeted to glial modulation in BD.

S100 proteins in cancer

In humans, the S100 protein family is composed of 21 members that exhibit a high degree of structural similarity, but are not functionally interchangeable. This family of proteins modulates cellular responses by functioning both as intracellular Ca(2+) sensors and as extracellular factors. Dysregulated expression of multiple members of the S100 family is a common feature of human cancers, with each type of cancer showing a unique S100 protein profile or signature. Emerging in vivo evidence indicates that the biology of most S100 proteins is complex and multifactorial, and that these proteins actively contribute to tumorigenic processes such as cell proliferation, metastasis, angiogenesis and immune evasion. Drug discovery efforts have identified leads for inhibiting several S100 family members, and two of the identified inhibitors have progressed to clinical trials in patients with cancer. This Review highlights new findings regarding the role of S100 family members in cancer diagnosis and treatment, the contribution of S100 signalling to tumour biology, and the discovery and development of S100 inhibitors for treating cancer.

The heavy chain has its day: regulation of myosin-II assembly

Nonmuscle myosin-II is an actin-based motor that converts chemical energy into force and movement, and thus functions as a key regulator of the eukaryotic cytoskeleton. Although it is established that phosphorylation on the regulatory light chain increases the actin-activated MgATPase activity of the motor and promotes myosin-II filament assembly, studies have begun to characterize alternative mechanisms that regulate filament assembly and disassembly. These investigations have revealed that all three nonmuscle myosin-II isoforms are subject to additional regulatory controls, which impact diverse cellular processes. In this review, we discuss current knowledge on mechanisms that regulate the oligomerization state of nonmuscle myosin-II filaments by targeting the myosin heavy chain.

S100A3 suppression inhibits in vitro and in vivo tumor growth and invasion of human castration-resistant prostate cancer cells

OBJECTIVE

To investigate the role of S100A3 and the effect of S100A3 inhibition on human castration-resistant prostate cancer (CRPC) cells by using in vitro and in vivo functional assays.

MATERIALS AND METHODS

Using human CRPC cells (PC3 and DU145), S100A3 expression levels were assessed by reverse transcription-polymerase chain reaction and Western blot analysis. After S100A3-specific small interfering ribonucleic acid (RNA) treatment, cell viability was determined by Cell Counting Kit-8 assay, and apoptotic cell fractions were evaluated by flow cytometry. The invasive properties of these cells and the expression pattern of matrix metalloproteinases (MMPs) were assessed using transwell migration assays, reverse transcription-polymerase chain reaction, and gelatin zymography. Finally, the in vivo efficacy of S100A3 inhibition on human CRPC cells was investigated using human tumor xenograft models in nude mice.

RESULTS

Human CRPC cells showed overexpression of S100A3, and its suppression reduced cell viability owing to apoptotic cell death. Additionally, S100A3 inhibition decreased the invasiveness of human CRPC cells. Moreover, MMP-2 and MMP-9 were downregulated in PC3, whereas only MMP-9 was downregulated in D145 after S100A3 inhibition. In human CRPC xenograft models, we noted a marked reduction in tumor growth in mice injected with S100A3 short hairpin RNA-transfected PC3 and DU145 cells.

CONCLUSION

Human CRPC cells showed upregulation of S100A3 expression, and S100A3 inhibition reduced tumor cell viability. S100A3 inhibition reduced invasion capability with downregulation of MMP expression. More importantly, S100A3 inhibition resulted in tumor growth suppression in human CRPC xenograft models, suggesting S100A3 could serve as a novel therapeutic target for the treatment of human CRPC.

Alterations of the biomarker S-100B and NSE in patients with acute vertebral spine fractures

BACKGROUND CONTEXT

Although several publications concerning the use of the biomarkers S100B and neuron-specific enolase (NSE) in vertebral spine fractures in animal experimental studies have proven their usefulness as early indicators of injury severity, there are no clinical reports on their effectiveness as indicators in patients with spinal injuries. As these biomarkers have been examined, with promising results, in patients with traumatic brain injury, there is a potential for their implementation in patients with vertebral spine fractures.

PURPOSE

To investigate the early serum measurement of S100B and NSE in patients with vertebral spine fractures compared with those in patients with acute fractures of the proximal femur.

STUDY DESIGN

Prospective longitudinal cohort study.

PATIENT SAMPLE

A cohort of 34 patients admitted over an 18-month period to a single medical center for suspected vertebral spine trauma. Twenty-nine patients were included in the control group.

OUTCOME MEASURES

S100B and NSE serum levels were assessed in different types of vertebral spine fractures.

METHODS

We included patients older than 16 years with vertebral spine fractures whose injuries were sustained within 24 hours before admission to the emergency room and who had undergone a brief neurologic examination. Spinal cord injuries (SCIs) were classified as being paresthesias, incomplete paraplegias, or complete paraplegias. Blood serum was obtained from all patients within 24 hours after the time of injury. Serum levels of S100B and NSE were statistically analyzed using Wilcoxon signed-rank test.

RESULTS

S100B serum levels were significantly higher in patients with vertebral spine fractures (p=.01). In these patients, the mean S100B serum level was 0.75 μg/L (standard deviation [SD] 1.44, 95% confidence interval [CI] 0.24, 1.25). The mean S100B serum level in control group patients was 0.14 μg/L (SD 0.11, 95% CI 0.10, 0.19). The 10 patients with neurologic deficits had significantly higher S100B serum levels compared with the patients with vertebral fractures but without neurologic deficits (p=.02). The mean S100B serum level in these patients was 1.18 μg/L (SD 1.96). In the 26 patients with vertebral spine fractures but without neurologic injury, the mean S100B serum level was 0.42 μg/L (SD 0.91, 95% CI 0.08, 0.76). The analysis revealed no significant difference in NSE levels.

CONCLUSIONS

We observed a significant correlation not only between S100B serum levels and vertebral spine fractures but also between S100B serum levels and SCIs with neurologic deficit. These results may be meaningful in clinical practice and to future studies.

Analyzing the blood-brain barrier: the benefits of medical imaging in research and clinical practice

A dysfunctional BBB is a common feature in a variety of brain disorders, a fact stressing the need for diagnostic tools designed to assess brain vessels' permeability in space and time. Biological research has benefited over the years various means to analyze BBB integrity. The use of biomarkers for improper BBB functionality is abundant. Systemic administration of BBB impermeable tracers can both visualize brain regions characterized by BBB impairment, as well as lead to its quantification. Additionally, locating molecular, physiological content in regions from which it is restricted under normal BBB functionality undoubtedly indicates brain pathology-related BBB disruption. However, in-depth research into the BBB's phenotype demands higher analytical complexity than functional vs. pathological BBB; criteria which biomarker based BBB permeability analyses do not meet. The involvement of accurate and engineering sciences in recent brain research, has led to improvements in the field, in the form of more accurate, sensitive imaging-based methods. Improvements in the spatiotemporal resolution of many imaging modalities and in image processing techniques, make up for the inadequacies of biomarker based analyses. In pre-clinical research, imaging approaches involving invasive procedures, enable microscopic evaluation of BBB integrity, and benefit high levels of sensitivity and accuracy. However, invasive techniques may alter normal physiological function, thus generating a modality-based impact on vessel's permeability, which needs to be corrected for. Non-invasive approaches do not affect proper functionality of the inspected system, but lack in spatiotemporal resolution. Nevertheless, the benefit of medical imaging, even in pre-clinical phases, outweighs its disadvantages. The innovations in pre-clinical imaging and the development of novel processing techniques, have led to their implementation in clinical use as well. Specialized analyses of vessels' permeability add valuable information to standard anatomical inspections which do not take the latter into consideration.

GFAP out-performs S100β in detecting traumatic intracranial lesions on computed tomography in trauma patients with mild traumatic brain injury and those with extracranial lesions

Both glial fibrillary acidic protein (GFAP) and S100β are found in glial cells and are released into serum following a traumatic brain injury (TBI), however, the clinical utility of S100β as a biomarker has been questioned because of its release from bone. This study examined the ability of GFAP and S100β to detect intracranial lesions on computed tomography (CT) in trauma patients and also assessed biomarker performance in patients with fractures and extracranial injuries on head CT. This prospective cohort study enrolled a convenience sample of adult trauma patients at a Level I trauma center with and without mild or moderate traumatic brain injury (MMTBI). Serum samples were obtained within 4 h of injury. The primary outcome was the presence of traumatic intracranial lesions on CT scan. There were 397 general trauma patients enrolled: 209 (53%) had a MMTBI and 188 (47%) had trauma without MMTBI. Of the 262 patients with a head CT, 20 (8%) had intracranial lesions. There were 137 (35%) trauma patients who sustained extracranial fractures below the head to the torso and extremities. Levels of S100β were significantly higher in patients with fractures, compared with those without fractures (p<0.001) whether MMTBI was present or not. However, GFAP levels were not significantly affected by the presence of fractures (p>0.05). The area under the receiver operating characteristics curve (AUC) for predicting intracranial lesions on CT for GFAP was 0.84 (0.73-0.95) and for S100β was 0.78 (0.67-0.89). However, in the presence of extracranial fractures, the AUC for GFAP increased to 0.93 (0.86-1.00) and for S100β decreased to 0.75 (0.61-0.88). In a general trauma population, GFAP out-performed S100β in detecting intracranial CT lesions, particularly in the setting of extracranial fractures.

Comparison of mRNA, Protein, and Urinary Nucleic Acid Levels of S100A8 and S100A9 between Prostate Cancer and BPH

BACKGROUND

Infections and inflammation in the prostate play a critical role in carcinogenesis, and S100A8 and S100A9 are key mediators in acute and chronic inflammation. Therefore, we investigated the differences of S100A8/A9 expression between prostate cancer (CaP) and benign prostatic hyperplasia (BPH) tissues, and we evaluated the possibilities of urinary nucleic acids of S100A8/A9 as diagnostic and prognostic markers.

METHODS

Tissues from 132 CaP patients who underwent prostatectomy or transurethral resection and 90 BPH patients who underwent transurethral prostatectomy were assessed.sd In addition, S100A8 and S100A9 nucleic acid levels were measured in the urine of 283 CaP patients and 363 BPH controls.

RESULTS

S100A8 and S100A9 mRNA levels were lower in CaP than BPH tissues (P < 0.001). S100A8 and S100A9 expression was increased in cancer tissues with poorer prognosis. In 69 specimens from prostatectomy patients, S100A8/A9 were the independent predictor of biochemical recurrence (hazard ratio 5.22, 95 % confidence interval 1.800-15.155, P = 0.002). Immunohistochemical staining revealed that BPH tissues stained more strongly for both S100A8 and S100A9 than CaP tissues (P < 0.001). S100A8 and S100A9 urinary nucleic acid levels were lower in CaP than in BPH (P = 0.001 and <0.001, respectively).

CONCLUSIONS

S100A8/A9 levels are lower in CaP than in BPH. Both were more highly expressed in patients with aggressive disease and shorter biochemical recurrence-free time. S100A8/A9 urinary cell-free nucleic acid levels correlated positively with expression levels obtained from tissue staining. Therefore, S100A8/A9 measurement in tissues and urine may have diagnostic and prognostic value in CaP.

Localization of S-100 proteins in the testis and epididymis of poultry and rabbits

The present investigation was conducted to demonstrate S-100 protein in the testis and epididymis of adult chickens, Sudani ducks, pigeons, and rabbits. This study may represent the first indication for the presence of S-100 in the male reproductive organs of these species and might therefore serve as a milestone for further reports. In the testis of chickens, pigeons and rabbits, intense S-100 was seen in Sertoli cells. S-100 was also seen in the endothelial lining of blood vessels in rabbit testis. On the contrary, no S-100 reaction was detected in the Sertoli cells of Sudani ducks. In epididymis, the localization of S-100 had varied according to species studied; it was seen in the basal cells (BC) of epididymal duct in duck, non-ciliated cells of the distal efferent ductules in pigeons and ciliated cells of the efferent ductules and BC of rabbit epididymis. Conversely, S-100 specific staining was not detected in the epithelial lining of the rooster and pigeon epididymal duct as well as the principal cells of the rabbit epididymis. In conclusion, the distribution of the S-100 proteins in the testis and epididymis might point out to its roles in the male reproduction.

Metals in protein-protein interfaces

From the catalytic reactions that sustain the global oxygen, nitrogen, and carbon cycles to the stabilization of DNA processing proteins, transition metal ions and metallocofactors play key roles in biology. Although the exquisite interplay between metal ions and protein scaffolds has been studied extensively, the fact that the biological roles of the metals often stem from their placement in the interfaces between proteins and protein subunits is not always recognized. Interfacial metal ions stabilize permanent or transient protein-protein interactions, enable protein complexes involved in cellular signaling to adopt distinct conformations in response to environmental stimuli, and catalyze challenging chemical reactions that are uniquely performed by multisubunit protein complexes. This review provides a structural survey of transition metal ions and metallocofactors found in protein-protein interfaces, along with a series of selected examples that illustrate their diverse biological utility and significance.

Transgenic rat model of Huntington's disease: a histopathological study and correlations with neurodegenerative process in the brain of HD patients

Rats transgenic for Huntington's disease (tgHD51 CAG rats), surviving up to two years, represent an animal model of HD similar to the late-onset form of human disease. This enables us to follow histopathological changes in course of neurodegenerative process (NDP) within the striatum and compare them with postmortem samples of human HD brains. A basic difference between HD pathology in human and tgHD51 rats is in the rate of NDP progression that originates primarily from slow neuronal degeneration consequently resulting in lesser extent of concomitant reactive gliosis in the brain of tgHD51 rats. Although larger amount of striatal neurons displays only gradual decrease in their size, their number is significantly reduced in the oldest tgHD51 rats. Our quantitative analysis proved that the end of the first year represents the turn in the development of morphological changes related to the progression of NDP in tgHD51 rats. Our data also support the view that all types of CNS glial cells play an important, irreplaceable role in NDP. To the best of our knowledge, our findings are the first to document that tgHD51 CAG rats can be used as a valid animal model for detailed histopathological studies related to HD in human.

Proteomics-Based Identification of Differentially Abundant Proteins from Human Keratinocytes Exposed to Arsenic Trioxide

INTRODUCTION

Arsenic is a widely distributed environmental toxicant that can cause multi-tissue pathologies. Proteomic assays allow for the identification of biological processes modulated by arsenic in diverse tissue types.

METHOD

The altered abundance of proteins from HaCaT human keratinocyte cell line exposed to arsenic was quantified using a label-free LC-MS/MS mass spectrometry workflow. Selected proteomics results were validated using western blot and RT-PCR. A functional annotation analytics strategy that included visual analytical integration of heterogeneous data sets was developed to elucidate functional categories. The annotations integrated were mainly tissue localization, biological process and gene family.

RESULT

The abundance of 173 proteins was altered in keratinocytes exposed to arsenic; in which 96 proteins had increased abundance while 77 proteins had decreased abundance. These proteins were also classified into 69 Gene Ontology biological process terms. The increased abundance of transferrin receptor protein (TFRC) was validated and also annotated to participate in response to hypoxia. A total of 33 proteins (11 increased abundance and 22 decreased abundance) were associated with 18 metabolic process terms. The Glutamate--cysteine ligase catalytic subunit (GCLC), the only protein annotated with the term sulfur amino acid metabolism process, had increased abundance while succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial precursor (SDHB), a tumor suppressor, had decreased abundance.

CONCLUSION

A list of 173 differentially abundant proteins in response to arsenic trioxide was grouped using three major functional annotations covering tissue localization, biological process and protein families. A possible explanation for hyperpigmentation pathologies observed in arsenic toxicity is that arsenic exposure leads to increased iron uptake in the normally hypoxic human skin. The proteins mapped to metabolic process terms and differentially abundant are candidates for evaluating metabolic pathways perturbed by arsenicals.

Phenomenon of painless knee in recurrent patellar dislocation in children

INTRODUCTION

Cartilage lesion with patellar malalignment may be correlated with pain. Situations in which patients with recurrent patellar dislocation are painless between episodes of luxation can be approached with considerable curiosity. We evaluated the distribution of substance-P and S-100 protein expression in soft tissue of the knee in children with recurrent patellar dislocation, in order to evaluate the distribution of nociceptors and determine tissue origins of this situation.

MATERIAL AND METHODS

Samples were collected from the medial and lateral synovial membrane, medial and lateral patellar retinaculum, Hoffa's body, patellar ligament, and quadriceps' aponeurosis in 10 children during the Blauth procedure and 10 adults with idiopathic osteoarthritis during total joint alloplasty. The density of nociceptive fibres was compared in the children and adults using S-100 and substance-P monoclonal antibodies.

RESULTS

Statistical differences between groups were demonstrated for S-100 expression in synovial membrane of the medial knee compartment (p < 0.05) and for substance-P expression in the medial patellar retinaculum (p < 0.05) and synovial membrane of the lateral (p < 0.05) and medial (p < 0.05) knee compartment in favour of children.

CONCLUSIONS

Lack of pain sensations in patients with recurrent patellar dislocation may be associated with non-increased expression of nerve endings in Hoffa's body. Increased expression of either S-100 protein or substance-P in synovial membrane and the medial retinaculum did not induce pain development in the knee joints of that group of patients.

S100A2 protein and non-small cell lung cancer. The dual role concept

S100A2 is a member of the EF-hand motif family S100. Its role has been recently implicated in carcinogenesis and metastasis. Although its precise role in NSCLC patients is debated and conflicting results have been published, it has been associated with patient survival. S100A2 expression was downregulated in some studies while others disagree that S100A2 is strongly expressed in lung cancer. It has been recently published by Hountis et al. that there is a significant association between nuclear S100A2 positivity and better disease-free interval. Intensity of expression was the highest in the early and advanced stages, and equally distributed in the middle stages. This is indicative for a dual role of this protein in carcinogenesis. The expression of S100A2 in operable NSCLC varies widely, and this differential location and expression pattern (nuclear or cytoplasmic or both) seem to correlate with prognosis. The precise role for the movement of S100A2 protein between cytoplasm and nucleus is still unclear. We present here a literature review, and we propose the dual concept on its substantial role as a prognostic or predictive indicator in this unfavorable group of patients.

Joining S100 proteins and migration: for better or for worse, in sickness and in health

The vast diversity of S100 proteins has demonstrated a multitude of biological correlations with cell growth, cell differentiation and cell survival in numerous physiological and pathological conditions in all cells of the body. This review summarises some of the reported regulatory functions of S100 proteins (namely S100A1, S100A2, S100A4, S100A6, S100A7, S100A8/S100A9, S100A10, S100A11, S100A12, S100B and S100P) on cellular migration and invasion, established in both culture and animal model systems and the possible mechanisms that have been proposed to be responsible. These mechanisms involve intracellular events and components of the cytoskeletal organisation (actin/myosin filaments, intermediate filaments and microtubules) as well as extracellular signalling at different cell surface receptors (RAGE and integrins). Finally, we shall attempt to demonstrate how aberrant expression of the S100 proteins may lead to pathological events and human disorders and furthermore provide a rationale to possibly explain why the expression of some of the S100 proteins (mainly S100A4 and S100P) has led to conflicting results on motility, depending on the cells used.

Serum S100B represents a new biomarker for mood disorders

Recently, mood disorders have been discussed to be characterized by glial pathology. The protein S100B, a growth and differentiation factor, is located in, and may actively be released by astro- and oligodendrocytes. This protein is easily assessed in human serum and provides a useful parameter for glial activation or injury. Here, we review studies investigating the glial marker S100B in serum of patients with mood disorders. Studies consistently show that S100B is elevated in mood disorders; more strongly in major depressive than bipolar disorder. Consistent with the glial hypothesis of mood disorders, serum S100B levels interact with age with higher levels in elderly depressed subjects. Successful antidepressive treatment has been associated with serum S100B reduction in major depression, whereas there is no evidence of treatment effects in mania. In contrast to the glial marker S100B, the neuronal marker protein neuron-specific enolase is unaltered in mood disorders. Recently, serum S100B has been linked to specific imaging parameters in the human white matter suggesting a role for S100B as an oligodendrocytic marker protein. In sum, serum S100B can be regarded as a promising in vivo biomarker for mood disorders deepening the understanding of the pathogenesis and plasticity-changes in these disorders. Future longitudinal studies combining serum S100B with other cell-specific serum parameters and multimodal imaging are warranted to further explore this serum protein in the development, monitoring and treatment of mood disorders.

S100 family signaling network and related proteins in pancreatic cancer (Review)

The occurrence and development of pancreatic cancer is a complex process convoluted by multi-pathogenies, multi-stages and multi-factors. S100 proteins are members of the S100 family that regulate multiple cellular pathways related to pancreatic cancer progression and metastasis. S100 proteins have a broad range of intracellular and extracellular functions, including the regulation of protein phosphorylation and enzyme activity, calcium homeostasis and the regulation of cytoskeletal components and transcriptional factors. S100 proteins interact with receptor for advanced glycation end-products (RAGE), p53 and p21, which play a role in the degradation of the extracellular matrix (ECM) and metastasis, and also interact with cytoskeletal proteins and the plasma membrane in pancreatic cancer progression and metastasis. S100A11 and S100P are significant tumor markers for pancreatic cancer and unfavorable predictors for the prognosis of patients who have undergone surgical resection. Recently, S100A2 has been suggested to be a negative prognostic biomarker in pancreatic cancer, and the expression of S100A6 may be an independent prognostic impact factor. The expression of S100A4 and S100P is associated with drug resistance, differentiation, metastasis and clinical outcome. This review summarizes the role and significance of the S100 family signaling network and related proteins in pancreatic cancer.

Complex formation between S100B protein and the p90 ribosomal S6 kinase (RSK) in malignant melanoma is calcium-dependent and inhibits extracellular signal-regulated kinase (ERK)-mediated phosphorylation of RSK

S100B is a prognostic marker for malignant melanoma. Increasing S100B levels are predictive of advancing disease stage, increased recurrence, and low overall survival in malignant melanoma patients. Using S100B overexpression and shRNA(S100B) knockdown studies in melanoma cell lines, elevated S100B was found to enhance cell viability and modulate MAPK signaling by binding directly to the p90 ribosomal S6 kinase (RSK). S100B-RSK complex formation was shown to be Ca(2+)-dependent and to block ERK-dependent phosphorylation of RSK, at Thr-573, in its C-terminal kinase domain. Additionally, the overexpression of S100B sequesters RSK into the cytosol and prevents it from acting on nuclear targets. Thus, elevated S100B contributes to abnormal ERK/RSK signaling and increased cell survival in malignant melanoma.