Prognostic value of the S100B protein in newly diagnosed and recurrent glioma patients: a serial analysis

Dietary EPA and DHA enrichment of a high fat diet during doxorubicin-based chemotherapy attenuated neuroinflammatory gene expression in the brain of C57bl/6 ovariectomized mice

Chemotherapy agents in breast cancer are associated with chemotherapy-related cognitive impairments (CRCI). Mechanisms are not fully clear, but alterations of glucose and lipid metabolism, neuroinflammation and neurodegeneration may contribute to CRCI. The aim of this study was to investigate the combined effects of a high fat (HF) diet combined with doxorubicin-based chemotherapy on glucose and lipid metabolism, neuroinflammation, and neurodegeneration in mice. Additionally, we examined the therapeutic potential of dietary eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) to attenuate these effects. Female C57Bl/6 mice (n = 42) were fed HF, HFn-3 (2 % kcals as EPA + DHA) or Low Fat (LF) diets for seven weeks, with and without chemotherapy. In this study, two chemotherapy injections led to weight and body fat loss associated with a decrease in insulin resistance measured by HOMA-IR. HOMA-IR was significantly greater in HF versus LF groups; but HOMA-IR in HFn-3 group did not significantly differ from either HF or LF groups. Chemotherapy resulted in higher brain concentrations of the inflammatory chemokine KC/GRO. Compared to LF diet plus chemotherapy, HF diet plus chemotherapy upregulated multiple genes involved in neuroinflammation and neurodegeneration pathways. HFn-3 diet plus chemotherapy attenuated gene expression by downregulating multiple genes involved in neuroinflammation and blood brain barrier regulation, including Mapkapk2, Aqp4, and s100b, and upregulating Kcnb1 and Atxn3, genes involved in reduction of oxidative stress and anxiety, respectively. Overall, a HF diet combined with chemotherapy is associated with neuroinflammatory and neurodegenerative gene expression changes in this mouse model; dietary enrichment of EPA and DHA attenuated these effects. Further studies are needed to understand how diet impacts behavioral outcomes of CRCI.

TAT-W61 peptide attenuates neuronal injury through blocking the binding of S100b to the V-domain of Rage during ischemic stroke

Ischemic stroke is a devastative nervous system disease associated with high mortality and morbidity rates. Unfortunately, no clinically effective neuroprotective drugs are available now. In ischemic stroke, S100 calcium-binding protein b (S100b) binds to receptor for advanced glycation end products (Rage), leading to the neurological injury. Therefore, disruption of the interaction between S100B and Rage can rescue neuronal cells. Here, we designed a peptide, termed TAT-W61, derived from the V domain of Rage which can recognize S100b. Intriguingly, TAT-W61 can reduce the inflammatory caused by ischemic stroke through the direct binding to S100b. The further investigation demonstrated that TAT-W61 can improve pathological infarct volume and reduce the apoptotic rate. Particularly, TAT-W61 significantly improved the learning ability, memory, and motor dysfunction of the mouse in the ischemic stroke model. Our study provides a mechanistic insight into the abnormal expression of S100b and Rage in ischemic stroke and yields an invaluable candidate for the development of drugs in tackling ischemic stroke. KEY MESSAGES: S100b expression is higher in ischemic stroke, in association with a high expression of many genes, especially of Rage. S100b is directly bound to the V-domain of Rage. Blocking the binding of S100b to Rage improves the injury after ischemic stroke.

Changes in CA15-3, S100B, and IGF-1 in glioma and their predictive value for treatment efficacy

OBJECTIVE

To analyze the changes of carbohydrate antigen 153 (CA15-3), S-100 calcium-binding protein B (S100B) and insulin-like growth factor-1 (IGF-1) in the treatment of patients with high-grade glioma and their predictive value for efficacy.

METHODS

In this retrospective the PG and CG study, 74 patients with glioma who were treated in the Affiliated Hospital of Yan'an University from January 2015 to January 2017 were labeled as the patient group (PG); the other 70 patients who underwent craniocerebral trauma surgery during the same period were selected as the control group (CG). The expressions of CA15-3, S100B and IGF-1 in the PG and CG were compared. The relationship between CA15-3, S100B, IGF-1, and the pathologic data of patients was analyzed. The expression differences of CA15-3, S100B, and IGF-1 were compared between low-grade glioma patients and high-grade glioma patients and their diagnostic value was analyzed. The values of CA15-3, S100B, and IGF-1 expression for predicting treatment efficacy were analyzed.

RESULTS

Expressions of CA15-3, S100B, and IGF-1 in glioma patients were markedly higher than those in the CG (P<0.0001). The proportion of grade III+IV patients with high expression of CA15-3, S100B, and IGF-1 was higher than in grade II patients (P<0.05), and the expressions of CA15-3, S100B and IGF-1 in low-grade glioma patients were lower than in high-grade glioma (P<0.01). The AUCs of CA15-3, S100B, and IGF-1 in differentiating different grades of glioma were 0.822, 0.722, and 0.768, respectively. Serum CA15-3, S100B and IGF-1 levels of the patients after treatment were significantly lower than those before treatment (P<0.0001). With the deterioration of clinical efficacy, serum levels of CA15-3, S100B, and IGF-1 gradually increased (P<0.05), and CA15-3, S100B and IGF-1 were positively correlated with therapeutic efficacy (P<0.05). AUCs of CA15-3, S100B, and IGF-1 for predicting the clinical efficacy in glioma patients were 0.824, 0.741, and 0.800, respectively.

CONCLUSION

CA15-3, S100B, and IGF-1 are highly expressed in patients with glioma. They are diagnostic indicators to distinguish patients with high-grade glioma, and have predictive value for treatment efficacy.

The Role of the S100 Protein Family in Glioma

The S100 protein family consists of 25 members and share a common structure defined in part by the Ca²⁺ binding EF-hand motif. Multiple members' dysregulated expression is associated with progression, diagnosis and prognosis in a broad range of diseases, especially in tumors. They could exert wide range of functions both in intracellular and extracellular, including cell proliferation, cell differentiation, cell motility, enzyme activities, immune responses, cytoskeleton dynamics, Ca²⁺ homeostasis and angiogenesis. Gliomas are the most prevalent primary tumors of the brain and spinal cord with multiple subtypes that are diagnosed and classified based on histopathology. Up to now the role of several S100 proteins in gliomas have been explored. S100A8, S100A9 and S100B were highly expression in serum and may present as a marker correlated with survival and prognosis of glioma patients. Individual member was confirmed as a new regulator of glioma stem cells (GSCs) and a mediator of mesenchymal transition in glioblastoma (GBM). Additionally, several members up- or downregulation have been reported to involve in the development of glioma by interacting with signaling pathways and target proteins. Here we detail S100 proteins that are associated with glioma, and discuss their potential effects on progression, diagnosis and prognosis.

Pediatric Brain Tumors: Signatures from the Intact Proteome

The present investigation aimed to explore the intact proteome of tissues of pediatric brain tumors of different WHO grades and localizations, including medulloblastoma, pilocytic astrocytoma, and glioblastoma, in comparison with the available data on ependymoma, to contribute to the understanding of the molecular mechanisms underlying the onset and progression of these pathologies. Tissues have been homogenized in acidic water−acetonitrile solutions containing proteases inhibitors and analyzed by LC−high resolution MS for proteomic characterization and label-free relative quantitation. Tandem MS spectra have been analyzed by either manual inspection or software elaboration, followed by experimental/theoretical MS fragmentation data comparison by bioinformatic tools. Statistically significant differences in protein/peptide levels between the different tumor histotypes have been evaluated by ANOVA test and Tukey’s post-hoc test, considering a p-value > 0.05 as significant. Together with intact protein and peptide chains, in the range of molecular mass of 1.3−22.8 kDa, several naturally occurring fragments from major proteins, peptides, and proteoforms have been also identified, some exhibiting proper biological activities. Protein and peptide sequencing allowed for the identification of different post-translational modifications, with acetylations, oxidations, citrullinations, deamidations, and C-terminal truncations being the most frequently characterized. C-terminal truncations, lacking from two to four amino acid residues, particularly characterizing the β-thymosin peptides and ubiquitin, showed a different modulation in the diverse tumors studied. With respect to the other tumors, medulloblastoma, the most frequent malignant brain tumor of the pediatric age, was characterized by higher levels of thymosin β4 and β10 peptides, the latter and its des-IS form particularly marking this histotype. The distribution pattern of the C-terminal truncated forms was also different in glioblastoma, particularly underlying gender differences, according to the definition of male and female glioblastoma as biologically distinct diseases. Glioblastoma was also distinguished for the peculiar identification of the truncated form of the α-hemoglobin chain, lacking the C-terminal arginine, and exhibiting oxygen-binding and vasoconstrictive properties different from the intact form. The proteomic characterization of the undigested proteome, following the top-down approach, was challenging to originally investigate the post-translational events that differently characterize pediatric brain tumors. This study provides a contribution to elucidate the molecular profiles of the solid tumors most frequently affecting the pediatric age, and which are characterized by different grades of aggressiveness and localization.

Necrotic reshaping of the glioma microenvironment drives disease progression

Glioblastoma is the most common primary brain tumor and has a dismal prognosis. The development of central necrosis represents a tipping point in the evolution of these tumors that foreshadows aggressive expansion, swiftly leading to mortality. The onset of necrosis, severe hypoxia and associated radial glioma expansion correlates with dramatic tumor microenvironment (TME) alterations that accelerate tumor growth. In the past, most have concluded that hypoxia and necrosis must arise due to "cancer outgrowing its blood supply" when rapid tumor growth outpaces metabolic supply, leading to diffusion-limited hypoxia. However, growing evidence suggests that microscopic intravascular thrombosis driven by the neoplastic overexpression of pro-coagulants attenuates glioma blood supply (perfusion-limited hypoxia), leading to TME restructuring that includes breakdown of the blood-brain barrier, immunosuppressive immune cell accumulation, microvascular hyperproliferation, glioma stem cell enrichment and tumor cell migration outward. Cumulatively, these adaptations result in rapid tumor expansion, resistance to therapeutic interventions and clinical progression. To inform future translational investigations, the complex interplay among environmental cues and myriad cell types that contribute to this aggressive phenotype requires better understanding. This review focuses on contributions from intratumoral thrombosis, the effects of hypoxia and necrosis, the adaptive and innate immune responses, and the current state of targeted therapeutic interventions.

Blood-Based Biomarkers for Glioma in the Context of Gliomagenesis: A Systematic Review

BACKGROUND

Gliomas are the most common and aggressive tumors of the central nervous system. A robust and widely used blood-based biomarker for glioma has not yet been identified. In recent years, a plethora of new research on blood-based biomarkers for glial tumors has been published. In this review, we question which molecules, including proteins, nucleic acids, circulating cells, and metabolomics, are most promising blood-based biomarkers for glioma diagnosis, prognosis, monitoring and other purposes, and align them to the seminal processes of cancer.

METHODS

The Pubmed and Embase databases were systematically searched. Biomarkers were categorized in the identified biomolecules and biosources. Biomarker characteristics were assessed using the area under the curve (AUC), accuracy, sensitivity and/or specificity values and the degree of statistical significance among the assessed clinical groups was reported.

RESULTS

7,919 references were identified: 3,596 in PubMed and 4,323 in Embase. Following screening of titles, abstracts and availability of full-text, 262 articles were included in the final systematic review. Panels of multiple biomarkers together consistently reached AUCs >0.8 and accuracies >80% for various purposes but especially for diagnostics. The accuracy of single biomarkers, consisting of only one measurement, was far more variable, but single microRNAs and proteins are generally more promising as compared to other biomarker types.

CONCLUSION

Panels of microRNAs and proteins are most promising biomarkers, while single biomarkers such as GFAP, IL-10 and individual miRNAs also hold promise. It is possible that panels are more accurate once these are involved in different, complementary cancer-related molecular pathways, because not all pathways may be dysregulated in cancer patients. As biomarkers seem to be increasingly dysregulated in patients with short survival, higher tumor grades and more pathological tumor types, it can be hypothesized that more pathways are dysregulated as the degree of malignancy of the glial tumor increases. Despite, none of the biomarkers found in the literature search seem to be currently ready for clinical implementation, and most of the studies report only preliminary application of the identified biomarkers. Hence, large-scale validation of currently identified and potential novel biomarkers to show clinical utility is warranted.

Potential biomarkers of childhood brain tumor identified by proteomics of cerebrospinal fluid from extraventricular drainage (EVD)

Brain tumors are the most common solid tumors in childhood. There is the need for biomarkers of residual disease, therapy response and recurrence. Cerebrospinal fluid (CSF) is a source of brain tumor biomarkers. We analyzed the proteome of waste CSF from extraventricular drainage (EVD) from 29 children bearing different brain tumors and 17 controls needing EVD insertion for unrelated causes. 1598 and 1526 proteins were identified by liquid chromatography-coupled tandem mass spectrometry proteomics in CSF control and brain tumor patients, respectively, 263 and 191 proteins being exclusive of either condition. Bioinformatic analysis revealed promising protein biomarkers for the discrimination between control and tumor (TATA-binding protein-associated factor 15 and S100 protein B). Moreover, Thymosin beta-4 (TMSB4X) and CD109, and 14.3.3 and HSP90 alpha could discriminate among other brain tumors and low-grade gliomas plus glyoneuronal tumors/pilocytic astrocytoma, or embryonal tumors/medulloblastoma. Biomarkers were validated by ELISA assay. Our method was able to distinguish among brain tumor vs non-tumor/hemorrhagic conditions (controls) and to differentiate two large classes of brain tumors. Further prospective studies may assess whether the biomarkers proposed by our discovery approach can be identified in other bodily fluids, therefore less invasively, and are useful to guide therapy and predict recurrences.

Role of RAGE and Its Ligands on Inflammatory Responses to Brain Tumors

Gliomas, the most common form of brain cancer, can range from relatively slow-growing low-grade to highly aggressive glioblastoma that has a median overall survival of only 15 months despite multimodal standard therapy. Although immunotherapy with checkpoint inhibitors has significantly improved patient survival for some cancers, to date, these agents have not shown consistent efficacy against malignant gliomas. Therefore, there is a pressing need to better understand the impact of host inflammatory responses on the efficacy of emerging immunotherapy approaches for these resistant tumors. RAGE is a multi-ligand pattern recognition receptor that is activated in various inflammatory states such as diabetes, Alzheimer's disease, cystic fibrosis, and cancer. Low levels of RAGE can be found under normal physiological conditions in neurons, immune cells, activated endothelial, and vascular smooth muscle cells, but it is over-expressed under chronic inflammation due to the accumulation of its ligands. RAGE binds to a range of damage-associated molecular pattern molecules (DAMPs) including AGEs, HMGB1, S100s, and DNA which mediate downstream cellular responses that promote tumor growth, angiogenesis, and invasion. Both in vitro and in vivo studies have shown that inhibition of RAGE signaling can disrupt inflammation and cancer progression and metastasis. Here, we will review our current understanding of the role of RAGE pathway on glioma progression and how it could be exploited to improve the efficacy of immunotherapy approaches.

Friend or Foe: S100 Proteins in Cancer

S100 proteins are widely expressed small molecular EF-hand calcium-binding proteins of vertebrates, which are involved in numerous cellular processes, such as Ca²⁺ homeostasis, proliferation, apoptosis, differentiation, and inflammation. Although the complex network of S100 signalling is by far not fully deciphered, several S100 family members could be linked to a variety of diseases, such as inflammatory disorders, neurological diseases, and also cancer. The research of the past decades revealed that S100 proteins play a crucial role in the development and progression of many cancer types, such as breast cancer, lung cancer, and melanoma. Hence, S100 family members have also been shown to be promising diagnostic markers and possible novel targets for therapy. However, the current knowledge of S100 proteins is limited and more attention to this unique group of proteins is needed. Therefore, this review article summarises S100 proteins and their relation in different cancer types, while also providing an overview of novel therapeutic strategies for targeting S100 proteins for cancer treatment.

Interfering with S100B-effector protein interactions for cancer therapy

S100 calcium-binding protein B (S100B) is overexpressed in various malignant tumors, where it regulates cancer cell proliferation and metabolism by physical interactions with other molecules. Interfering with S100B-effector protein interactions is a potential strategy to treat malignant tumors. Although some S100B inhibitors have been discovered by virtual screening (VS), most target the S100B-p53 interaction. Hence, there is scope for the discovery of other S100B-effector protein interaction modulators for malignant tumors. In this review, we provide an overview of S100B-effector protein interaction inhibitor discovery using VS and discuss promising S100B-effector protein interaction targets that permit in silico analysis for drug discovery.

Unsupervised machine learning reveals risk stratifying glioblastoma tumor cells

A goal of cancer research is to reveal cell subsets linked to continuous clinical outcomes to generate new therapeutic and biomarker hypotheses. We introduce a machine learning algorithm, Risk Assessment Population IDentification (RAPID), that is unsupervised and automated, identifies phenotypically distinct cell populations, and determines whether these populations stratify patient survival. With a pilot mass cytometry dataset of 2 million cells from 28 glioblastomas, RAPID identified tumor cells whose abundance independently and continuously stratified patient survival. Statistical validation within the workflow included repeated runs of stochastic steps and cell subsampling. Biological validation used an orthogonal platform, immunohistochemistry, and a larger cohort of 73 glioblastoma patients to confirm the findings from the pilot cohort. RAPID was also validated to find known risk stratifying cells and features using published data from blood cancer. Thus, RAPID provides an automated, unsupervised approach for finding statistically and biologically significant cells using cytometry data from patient samples.

S100B as a biomarker for brain metastases in patients with non-small cell lung cancer

Brain metastases are frequent in patients with lung cancer and a major cause of morbidity and mortality. Finding a biomarker predicting brain metastases could facilitate early start of treatment and thereby reduce morbidity and possibly improve overall survival. Previous studies suggest S100B as a possible biomarker for this purpose. This prospective study enrolled 185 patients with newly diagnosed stage IV non-small cell lung cancer (NSCLC). A total of 22 patients had brain metastases verified by magnetic resonance imaging or computed tomography at the time of enrollment. Serum S100B levels were measured in blood samples collected prior to any treatment from 22 patients who had brain metastases at enrollment and from 50 patients randomly selected from the remaining 163 patients without brain metastases at enrollment. No statistically significant difference was found in the levels of serum S100B between patients with and without brain metastases [range 0.018-0.209 µg/l, mean 0.049 µg/l, 95% confidence interval (CI), 0.032-0.061 µg/l] and (range 0.016-0.130 µg/i, mean 0.044 µg/l, 95% CI, 0.037-0.051 µg/l), respectively, (P=0.852). Univariate analysis of prognostic factors for S100B indicated a correlation (P<0.2) with sex (P=0.088) and histology (adenocarcinoma vs. squamous cell carcinoma/others) (P=0.028). In the multivariate analysis only histology (P=0.029) remained statistically significant. Conclusion: The present study found no significant correlation between the level of serum S100B and the presence of brain metastases in patients with advanced NSCLC. The clear cut-off of S100B in patients with and without brain metastases reported in other studies could not be verified in this study. Further studies investigating the role of S100B as a biomarker for brain metastases in non-small cell lung cancer are warranted.

Pentamidine niosomes thwart S100B effects in human colon carcinoma biopsies favouring wtp53 rescue

S100B protein bridges chronic mucosal inflammation and colorectal cancer given its ability to activate NF-kappaB transcription via RAGE signalling and sequestrate pro-apoptotic wtp53. Being an S100B inhibitor, pentamidine antagonizes S100B-wtp53 interaction, restoring wtp53-mediated pro-apoptotic control in cancer cells in several types of tumours. The expression of S100B, pro-inflammatory molecules and wtp53 protein was evaluated in human biopsies deriving from controls, ulcerative colitis and colon cancer patients at baseline (a) and (b) following S100B targeting with niosomal PENtamidine VEhiculation (PENVE), to maximize drug permeabilization in the tissue. Cultured biopsies underwent immunoblot, EMSA, ELISA and biochemical assays for S100B and related pro-inflammatory/pro-apoptotic proteins. Exogenous S100B (0.005-5 μmol/L) alone, or in the presence of PENVE (0.005-5 μmol/L), was tested in control biopsies while PENVE (5 μmol/L) was evaluated on control, peritumoral, ulcerative colitis and colon cancer biopsies. Our data show that S100B level progressively increases in control, peritumoral, ulcerative colitis and colon cancer enabling a pro-inflammatory/angiogenic and antiapoptotic environment, featured by iNOS, VEGF and IL-6 up-regulation and wtp53 and Bax inhibition. PENVE inhibited S100B activity, reducing its capability to activate RAGE/phosphor-p38 MAPK/NF-kappaB and favouring its disengagement with wtp53. PENVE blocks S100B activity and rescues wtp53 expression determining pro-apoptotic control in colon cancer, suggesting pentamidine as a potential anticancer drug.

High-order radiomics features based on T2 FLAIR MRI predict multiple glioma immunohistochemical features: A more precise and personalized gliomas management

Objective

To investigate the performance of high-order radiomics features and models based on T2-weighted fluid-attenuated inversion recovery (T2 FLAIR) in predicting the immunohistochemical biomarkers of glioma, in order to execute a non-invasive, more precise and personalized glioma disease management.

Methods

51 pathologically confirmed gliomas patients committed in our hospital from March 2015 to June 2018 were retrospective analysis, and Ki-67, vimentin, S-100 and CD34 immunohistochemical data were collected. The volumes of interest (VOIs) were manually sketched and the radiomics features were extracted. Feature reduction was performed by ANOVA+ Mann-Whiney, spearman correlation analysis, least absolute shrinkage and selection operator (LASSO) and Gradient descent algorithm (GBDT). SMOTE technique was used to solve the data bias between two groups. Comprehensive binary logistic regression models were established. Area under the ROC curves (AUC), sensitivity, specificity and accuracy were used to evaluate the predict performance of models. Models reliability were decided according to the standard net benefit of the decision curves.

Results

Four clusters of significant features were screened out and four predicting models were constructed. AUC of Ki-67, S-100, vimentin and CD34 models were 0.713, 0.923, 0.854 and 0.745, respectively. The sensitivities were 0.692, 0.893, 0.875 and 0.556, respectively. The specificities were: 0.667, 0.905, 0.722, and 0.875, with accuracy of 0.660, 0.898, 0.738, and 0.667, respectively. According to the decision curves, the Ki-67, S-100 and vimentin models had reference values.

Conclusion

The radiomics features based on T2 FLAIR can potentially predict the Ki-67, S-100, vimentin and CD34 expression. Radiomics model were expected to be a computer-intelligent, non-invasive, accurate and personalized management method for gliomas.

S100B Protein Stimulates Proliferation and Angiogenic Mediators Release through RAGE/pAkt/mTOR Pathway in Human Colon Adenocarcinoma Caco-2 Cells

Chronic inflammation and angiogenesis are associated with colonic carcinogenesis. Enteric glia-derived S100B protein has been proposed as an "ideal bridge", linking colonic inflammation and cancer, given its dual ability to up-regulate nuclear factor-kappaB (NF-κB) transcription via receptor for advanced glycation end products (RAGE) signaling and to sequestrate wild type pro-apoptotic wild type (wt)p53. However, its pro-angiogenic effects on cancer cells are still uninvestigated. To this aim, we evaluated the effect of exogenous S100B (0.05-5 µM) protein alone or in the presence of S100B blocking monoclonal antibody (mAb) (1:10⁵-1:10⁴ v/v diluted) on (1) cultured Caco-2 cells proliferation, migration and invasiveness in vitro, respectively by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT)-formazan, wound healing and matrigel invasion assays and (2) its effect on the release of pro-angiogenic factors, such as vascular endothelial growth factor (VEGF) by ELISA and immunofluorescence analyses. The effect of S100B alone or in the presence of S100BmAb was then investigated on RAGE/pAkt/mammalian target of rapamycin (mTOR) signaling pathway by immunoblot analysis. Our results showed that S100B markedly increases proliferation and invasiveness of Caco-2 cells, through the release of pro-angiogenic VEGF and NO paralleled to a significant decrease of wtp53 expression mediated by RAGE-p38 mitogen-activated protein kinase (MAPK)/pAkt-mTOR and hypoxia-inducible factor 1-alpha (HIF1α) pathways. Such effects were counteracted by S100BmAb, indicating that S100B targeting is a potential approach to inhibit colon carcinoma proliferation and angiogenesis.

Effect of magnesium and lignocaine on post-craniotomy pain: A comparative, randomized, double blind, placebo-controlled study

Background:

Lignocaine and Magnesium have an analgesic action and reduce perioperative opioid requirements. We carried out this study to evaluate the effect of magnesium and lignocaine on postoperative pain as assessed using the visual analog scale (VAS) and fentanyl consumption. We also measured S-100 B levels and noted the side effect of drugs if any.

Materials and Methods:

In this prospective preliminary study, 45 patients undergoing supratentorial craniotomy for tumor surgery were randomized to receive either lignocaine (group I-1.5 mg/kg bolus followed by 2 mg/kg/h infusion), saline (Group II) or magnesium (group III: bolus of 50 mg/kg followed by 25 mg/kg/hr) intraoperatively. The amount of fentanyl required, VAS over first 24 hours and any side effects were noted. S100 B levels were also measured to assess brain protective effect of these drugs, if any. Appropriate statistical tests were applied for analysis of data and a P value < 0.05 was considered statistically significant.

Results:

None of the patient experienced any adverse hemodynamic effect intraoperatively secondary to the study drugs. The amount of intraoperative fentanyl consumption was comparable among the three groups. The mean VAS score was significantly less in group I and III [Group I (15.3 ± 6.0), Group II (24.8 ± 6.7), Group III (17.9 ± 7.6); (P < 0.01)]. The fentanyl consumed in first 24 hours was significantly less in those patients who received lignocaine and magnesium [Group I (204.4 ± 136.4), Group II (383 ± 168.2), Group III (194 ± 148.9); (P = 0.01)]. S100 value did not differ in the lignocaine and the saline group during the perioperative period. However, a significant decline was noted in the levels of S100 B in the magnesium group.

Conclusion:

Intraoperative infusion of lignocaine and magnesium results in lower VAS score and decreases the postoperative opioid requirement in patients undergoing craniotomy for excision of supratentorial tumors.

Association of S100B polymorphisms and serum S100B with risk of ischemic stroke in a Chinese population

The levels of serum S100B were elevated in patients with ischemic stroke (IS), which may be a novel biomarker for diagnosing IS. The aim of this study was to investigate the association of S100B polymorphisms and serum S100B with IS risk. We genotyped the S100B polymorphisms rs9722, rs9984765, rs2839356, rs1051169 and rs2186358 in 396 IS patients and 398 controls using polymerase chain reaction-single base extension (SBE-PCR). Serum S100B levels were measured by enzyme-linked immunosorbent assay (ELISA). Rs9722 was associated with an increased risk of IS (AA vs. GG: adjusted OR = 2.172, 95% CI, 1.175–4.014, P = 0.013; dominant: adjusted OR = 1.507, 95% CI, 1.071–2.123, P = 0.019; recessive: adjusted OR = 1.846, 95% CI, 1.025–3.323, P = 0.041; additive: adjusted OR=1.371, 95% CI, 1.109-1.694, P = 0.003). The A-C-C-C-A haplotype was associated with an increased risk of IS (OR = 1.325, 95% CI, 1.035–1.696, P = 0.025). In addition, individuals carrying the rs9722 GA/AA genotypes had a higher serum S100B compared with the rs9722 GG genotype in IS patients (P = 0.018). Our results suggest that the S100B gene rs9722 polymorphism may contribute to the susceptibility of IS, probably by promoting the expression of serum S100B.

S100A6 protein: functional roles

S100A6 protein belongs to the A group of the S100 protein family of Ca2+-binding proteins. It is expressed in a limited number of cell types in adult normal tissues and in several tumor cell types. As an intracellular protein, S100A6 has been implicated in the regulation of several cellular functions, such as proliferation, apoptosis, the cytoskeleton dynamics, and the cellular response to different stress factors. S100A6 can be secreted/released by certain cell types which points to extracellular effects of the protein. RAGE (receptor for advanced glycation endproducts) and integrin β1 transduce some extracellular S100A6's effects. Dosage of serum S100A6 might aid in diagnosis in oncology.