Targeted sequencing of cancer-related genes reveals a recurrent TOP2A variant which affects DNA binding and coincides with global transcriptional changes in glioblastoma.

High-grade gliomas are aggressive, deadly primary brain tumors. Median survival of patients with glioblastoma (GBM, WHO grade 4) is 14 months and <10% of patients survive 2 years. Despite improved surgical strategies and forceful radiotherapy and chemotherapy, the prognosis of GBM patients is poor and did not improve over decades. We performed targeted next-generation sequencing with a custom panel of 664 cancer- and epigenetics-related genes, and searched for somatic and germline variants in 180 gliomas of different WHO grades. Herein, we focus on 135 GBM IDH-wild type samples. In parallel, mRNA sequencing was accomplished to detect transcriptomic abnormalities. We present the genomic alterations in high-grade gliomas and the associated transcriptomic patterns. Computational analyses and biochemical assays showed the influence of TOP2A variants on enzyme activities. In 4/135 IDH-wild type GBMs we found a novel, recurrent mutation in the TOP2A gene encoding topoisomerase 2A (allele frequency [AF] = 0.03, 4/135 samples). Biochemical assays with recombinant, wild type (WT) and variant proteins demonstrated stronger DNA binding and relaxation activity of the variant protein. GBM patients carrying the altered TOP2A had shorter overall survival (median OS 150 vs 500 days, P = .0018). In the GBMs with the TOP2A variant we found transcriptomic alterations consistent with splicing dysregulation. luA novel, recurrent TOP2A mutation, which was found exclusively in four GBMs, results in the TOP2A E948Q variant with altered DNA binding and relaxation activities. The deleterious TOP2A mutation resulting in transcription deregulation in GBMs may contribute to disease pathology.

Alternative splicing of iodothyronine deiodinases in pituitary adenomas. Regulation by oncoprotein SF2/ASF.

Pituitary tumors belong to the group of most common neoplasms of the sellar region. Iodothyronine deiodinase types 1 (DIO1) and 2 (DIO2) are enzymes contributing to the levels of locally synthesized T3, a hormone regulating key physiological processes in the pituitary, including its development, cellular proliferation, and hormone secretion. Previous studies revealed that the expression of deiodinases in pituitary tumors is variable and, moreover, there is no correlation between mRNA and protein products of the particular gene, suggesting the potential role of posttranscriptional regulatory mechanisms. In this work we hypothesized that one of such mechanisms could be the alternative splicing. Therefore, we analyzed expression and sequences of DIO1 and DIO2 splicing variants in 30 pituitary adenomas and 9 non-tumorous pituitary samples. DIO2 mRNA was expressed as only two mRNA isoforms. In contrast, nine splice variants of DIO1 were identified. Among them, five were devoid of exon 3. In silico sequence analysis of DIO1 revealed multiple putative binding sites for splicing factor SF2/ASF, of which the top-ranked sites were located in exon 3. Silencing of SF2/ASF in pituitary tumor GH3 cells resulted in change of ratio between DIO1 isoforms with or without exon 3, favoring the expression of variants without exon 3. The expression of SF2/ASF mRNA in pituitary tumors was increased when compared with non-neoplastic control samples. In conclusion, we provide a new mechanism of posttranscriptional regulation of DIO1 and show deregulation of DIO1 expression in pituitary adenoma, possibly resulting from disturbed expression of SF2/ASF.

Microlesion effect as a predictor of the effectiveness of subthalamic deep brain stimulation for Parkinson's disease.

BACKGROUND: Microlesion effect (MLE) is a commonly observed phenomenon after electrode insertion into the subthalamic nucleus (STN) for deep brain stimulation (DBS). OBJECTIVES: The aim of this study was to determine the presence of the MLE in the early postoperative period and the relationship between MLE and STN DBS. METHODS: 74 patients with Parkinson's disease were included in this study. Motor symptoms were evaluated preoperatively, within 48 h after electrode implantation and at 6 months with United Parkinson's Disease Rating Scale part III (UPDRS-III). According to the improvement level with MLE, all participants were stratified into three groups: (1) less than 20%; (2) 20-40%, and (3) more than 40% in OFF medication states. The degree of improvement in UPDRS-III with DBS ON for each MLE group was assessed at the 6-month follow-up. Regression analysis was applied for the evaluation of the relationship between MLE and improvement with DBS ON. RESULTS: Mean results in UPDRS-III with the MLE in ON and OFF medication states were 22.1 ± 10.5 and 42.1 ± 14 points, respectively. At the 6-month follow-up, with active stimulation, results tended to further ameliorate to 14.6 (59.4%) points in ON and 20.8 (55.3%) in OFF. Mean improvement in MLE groups were: 33.6% group 1, 47.5% group 2 and 61.4% group 3. Regression analysis revealed a positive correlation between the MLE and results at 6 months with DBS ON. CONCLUSION: Results proved the presence of MLE in the early postoperative period. Furthermore, a positive correlation between MLE and improvement degree with active stimulation was observed.

Exploring Novel Therapeutic Opportunities for Glioblastoma Using Patient-Derived Cell Cultures.

Glioblastomas (GBM) are the most common, primary brain tumors in adults. Despite advances in neurosurgery and radio- and chemotherapy, the median survival of GBM patients is 15 months. Recent large-scale genomic, transcriptomic and epigenetic analyses have shown the cellular and molecular heterogeneity of GBMs, which hampers the outcomes of standard therapies. We have established 13 GBM-derived cell cultures from fresh tumor specimens and characterized them molecularly using RNA-seq, immunoblotting and immunocytochemistry. Evaluation of proneural (OLIG2, IDH1R132H, TP53 and PDGFRα), classical (EGFR) and mesenchymal markers (CHI3L1/YKL40, CD44 and phospho-STAT3), and the expression of pluripotency (SOX2, OLIG2, NESTIN) and differentiation (GFAP, MAP2, ß-Tubulin III) markers revealed the striking intertumor heterogeneity of primary GBM cell cultures. Upregulated expression of VIMENTIN, N-CADHERIN and CD44 at the mRNA/protein levels suggested increased epithelial-to-mesenchymal transition (EMT) in most studied cell cultures. The effects of temozolomide (TMZ) or doxorubicin (DOX) were tested in three GBM-derived cell cultures with different methylation status of the MGMT promoter. Amongst TMZ- or DOX-treated cultures, the strongest accumulation of the apoptotic markers caspase 7 and PARP were found in WG4 cells with methylated MGMT, suggesting that its methylation status predicts vulnerability to both drugs. As many GBM-derived cells showed high EGFR levels, we tested the effects of AG1478, an EGFR inhibitor, on downstream signaling pathways. AG1478 caused decreased levels of phospho-STAT3, and thus inhibition of active STAT3 augmented antitumor effects of DOX and TMZ in cells with methylated and intermediate status of MGMT. Altogether, our findings show that GBM-derived cell cultures mimic the considerable tumor heterogeneity, and that identifying patient-specific signaling vulnerabilities can assist in overcoming therapy resistance, by providing personalized combinatorial treatment recommendations.

Fluorescence-guided resection of primary and recurrent malignant gliomas with 5-aminolevulinic acid. Preliminary results.

BACKGROUND AND PURPOSE: Extent of resection plays a key role in the treatment of malignant gliomas (MGs). Patients with complete glioma removal, followed by chemoradiation, obtain the longest overall and progression-free survival. Fluorescence-guided resection of MGs enables intraoperative visualization of glioma tissue and increases control of the resection. The authors present preliminary results of 5-aminolevulinic acid (5-ALA) application during the resection of primary and recurrent MGs. MATERIAL AND METHODS: Six patients with either a suspected malignant glioma based on magnetic resonance imaging (MRI) or with recurrent glioblastoma multiforme were enrolled in the study. The extent of resection was calculated according to the postoperative MRI performed within 72 hours. Preoperative and early postoperative neurological status and Karnofsky Performance Scale (KPS) were compared. RESULTS: Fluorescence of tumour tissue was observed in 5/6 patients (five with the histopathological diagnosis of glioblastoma multiforme and one with neurotoxoplasmosis and AIDS). Complete tumour resection was achieved in 5 patients. Postoperative KPS and neurological status deteriorated in 2 cases. Radiotherapy and chemotherapy did not interfere with the sensitivity of the fluorescence guided tumour visualization. CONCLUSIONS: Fluorescence-guided resection of primary and recurrent MGs with 5-ALA improves control of the tumour resection. It enables the cytoreduction to be maximized but experience in neuro-oncological surgery is required to avoid serious, postoperative neurological deficits.

Statistical analysis of the intracranial procedures in Poland in 2008-2009.

BACKGROUND AND PURPOSE: Quantitative and qualitative analysis of neurosurgical procedures provides important data for assessment of the development and trends in the field of neurosurgery. The authors present statistical data on intracranial procedures (IPs) performed in Poland in 2008-2009. MATERIAL AND METHODS: Data on IPs come from reports of the National Health Fund, grouped according to the system of Diagnosis-Related Groups, group A - nervous system diseases. Data concerning the year 2009 include all IPs performed in Poland. Data from the second half of 2008 to 2009 (18 months) come from 35 neurosurgical centers in Poland, divided by provinces. We analyzed the number of IPs, the cost of procedures, duration of hospitalization and deaths. RESULTS: 20 849 IPs were performed in Poland in 2009. The most common procedure was A12 (6807; 32.65%), and the rarest was A04 (96; 0.46%). The annual cost of all IPs was 228 599 956 PLN. Average cost of the procedure ranged from 1578 PLN (A14) to 47 940 PLN (A03). Duration of the hospitalization ranged between 3 days (A14) and 12 days (A12). The highest percentage of deaths was reported for A01 (n = 1050, 19.06%). Reports from 35 neurosurgical centers in the second half of 2008 and 2009 showed the highest number of IPs per 100 000 population in Kujawsko-Pomorskie (93) and the lowest in Wielkopolskie (27) and Podkarpackie (27). The highest number of IPs (1669) was performed in neurosurgical center M1 (Malopolskie), and the lowest (99) in W1 (Wielkopolskie). CONCLUSIONS: A significant disparity in the number of IPs performed in different centers in Poland was observed.

Motor cortex stimulation in the treatment of neuropathic pain.

BACKGROUND AND PURPOSE: Despite the rapid development of neuropharmacotherapy, medical treatment of neuropathic pain (NP) still constitutes a significant socioeconomic problem. The authors herein present a group of patients treated with motor cortex stimulation (MCS) for NP of various types and aetiologies. MATERIAL AND METHODS: Our cohort included 12 female and 11 male NP patients aged 53 ± 16 treated with MCS. Eleven patients were diagnosed with neuropathic facial pain (NFP), 8 with hemi-body neuropathic pain (HNP), and 4 with deafferentation pain (DP). Prior to surgery, 16 out of 23 patients were treated with repetitive transcranial magnetic stimulation (rTMS), with a positive response in 10 cases. Pain intensity in our group was evaluated with the visual analogue scale (VAS) one month before and three months after MCS implantation. RESULTS: Improvement on the VAS was reported in the whole group of patients (p < 0.001). The best results were reported in the NFP group (p < 0.001) while the worst ones were noted in the DP group (p = 0.04). Anamnesis duration positively correlated with outcome. Infection forced the authors to permanently remove the system in one case. There were no other complications in the group. CONCLUSIONS: Minimally invasive, safe neuromodulative treatment with MCS permits neuropathic pain control with good efficacy. The type of neuropathic pain might be a prognostic factor.

Rosette-forming glioneuronal tumor of the fourth ventricle with advanced microvascular proliferation--a case report.

Rosette-forming glioneuronal tumor (RGNT) of the fourth ventricle is a recently described novel type of primary brain tumor that was included into the current WHO classification of CNS tumors. It is a very rare, slowly growing, mixed neoplasm at cerebellar localization with distinctive morphological pattern. We present an unusual case of a 20-year-old patient with RNGT of the fourth ventricle with advanced microvascular proliferation. MRI revealed the solid-cystic tumor mass largely involving the cerebellar vermis and left hemisphere with compression of the fourth ventricle. Microscopically, the tumor showed classical architectural pattern with two distinctive components. The main component consisted of neurocytic rosettes formed by round, isomorphic nuclei arranged around eosinophilic, fibrillar cores with strong synaptophysin expression. The perivascular rosettes with cell arrangement along blood vessels were observed only sporadically. The second neoplastic component consisted of spindle or stellate astroglial cells with piloid process and Rosenthal fibers, strongly resembling pilocytic astrocytoma. Focally, the astroglial cells showed increased cellularity but without marked nuclear atypia. The glial part of the tumor revealed advanced proliferation of microvessels. The vessels of glomeruloid type exhibited multilayered endothelial proliferation and marked mitotic activity. MIB1 labelling index was generally low; however, in areas exhibiting microvascular proliferation its expression was significantly increased up to 20%. This report demonstrates the unique case of RGNT with conspicuous microvascular proliferation of glomeruloid type and extensive endothelial proliferation. As there is still limited clinical experience with RGNT, further studies are necessary to evaluate the biology of this type of tumor.

[Hypothalamic deep brain stimulation for treatment of cluster headache]. / Stymulacja podwzgórza w leczeniu klasterowego bólu glowy.

Extremely severe, unilateral, recurrent facial pain and headache, accompanied by autonomic symptoms and signs, can be identified as cluster headache attacks (CH). Despite optimal pharmacological treatment, 20% of patients will not achieve satisfactory improvement. The severity of pain is so extreme that CH has been a cause of multiple suicidal attempts among patients ineffectively treated because of CH. Hypermetabolism of ipsilateral posterior hypothalamus observed in PET studies led to multiple attempts of deep brain stimulation (DBS) utilization in CH treatment. The authors present current opinions about DBS treatment in CH. A socioeconomic analysis of neuromodulatory treatment of CH is presented.

Thalamic deep brain stimulation in the treatment of essential tremor.

BACKGROUND AND PURPOSE: Quality of life can be severely impaired by essential tremor (ET) being the main cause of the patient's disability. The authors present a group of ET patients treated with deep brain stimulation of the ventral intermediate nucleus of the thalamus (Vim DBS). The aim of the study was to evaluate the efficacy and safety of Vim DBS in the treatment of ET. MATERIAL AND METHODS: Between 2006 and 2009, 8 female and 10 male ET patients were treated with Vim DBS. Mean age at implantation was 63 ± 15 years. ET lasted from 4 to 30 years (mean 12 years). Clinical condition of the group was evaluated before surgery and 3 months after implantation with spirography (spiral drawings), the modified Fahn (Tremor Rating Scale, TRS) scale, and the modified ADL (Activity of Daily Living) scale. The Vim was localized with CT and MRI. The procedures of implantation were performed under local and general anaesthesia. A bilateral procedure was performed in 11 cases and a unilateral procedure was performed in 7 cases. RESULTS: The therapeutic effect of DBS was maintained at the follow-up in the third month following surgery. Mean contralateral limb tremor reduction was 79%. Head tremor reduction was reported by 75% of patients in the bilateral Vim DBS subgroup and 50% of patients in the unilateral Vim DBS subgroup. Mean ADL score improved by 61%. CONCLUSIONS: Vim DBS is a safe and effective method of ET treatment. Vim DBS improves activities of daily living of ET patients.

Neuropsychological assessment of language functions during functional magnetic resonance imaging: development of new tasks. Preliminary report.

BACKGROUND AND PURPOSE: Due to the complex and extended cerebral organization of language functions, the brain regions crucial for speech and language, i.e. eloquent areas, have to be affected by neurooncological surgery. One of the techniques that may be helpful in pre-operative planning of the extent of tumour removal and estimating possible complications seems to be functional magnetic resonance imaging (fMRI). The aim of the study was to develop valid procedures for neuropsychological assessment of various language functions visualisable by fMRI in healthy individuals. MATERIAL AND METHODS: In this fMRI study, 10 healthy (with no CNS pathology), right-handed volunteers aged 25-35 were examined using four tasks designed to measure different language functions, and one for short-term memory assessment. A 1.5-T MRI scanner performing ultrafast functional (EPI) sequences with 4-mm slice thickness and 1-mm interslice gap was used to detect the BOLD response to stimuli present-ed in a block design (30-second alternating blocks of activity and rest). The analyses used the SPM software running in a MATLAB environment, and the obtained data were interpreted by means of colour-coded maps superimposed on structural brain scans. RESULTS: For each of the tasks developed for particular language functions, a different area of increased neuronal activity was found. CONCLUSIONS: The differential localization of function-related neuronal activity seems interesting and the research worth continuing, since verbal communication failure may result from impairment of any of various language functions, and studies reported in the literature seem to focus on verbal expression only.

Subthalamic deep brain stimulation for the treatment of Parkinson disease.

BACKGROUND AND PURPOSE: The role of subthalamic nucleus deep brain stimulation (STN DBS) in the treatment of Parkinson disease (PD) is well established. The authors present a group of patients diagnosed with PD who were treated with STN DBS. MATERIAL AND METHODS: Between 2008 and 2009, 32 female and 34 male patients with PD were treated with STN DBS. Mean age at implantation was 57 ± 12 years. PD lasted from 6 to 21 years (mean 10 years). Patients were qualified for the surgery according to the CAPSIT-PD criteria. The STN was identified with direct and indirect methods. Macrostimulation and microrecording for STN identification were used in all cases. A unilateral STN DBS system was implanted in two cases and bilateral implantation was performed among rest of the group. Outcome was assessed six months after implantation. Results : The mean reduction of UPDRS III score among 51 patients who underwent follow-up was 45% (5-89%). Reduction of levodopa consumption varied from 15 to 100%. Infection forced the authors to remove the DBS system in one case four months after implantation. Skin erosion above the internal pulse generator was noted in four cases. CONCLUSIONS: Cardinal symptoms of Parkinson's disease can be safely and effectively treated with STN DBS in selected group of patients.

[Orthostatic hypotension and supine hypertension in primary autonomic failure. Pathophysiology, diagnosis and treatment]. / Hipotonia ortostatyczna i nadcisnienie tetnicze w pozycji lezacej w pierwotnych zaburzeniach autonomicznych. Patofizjologia, diagnostyka i leczenie.

There are three diseases classified as primary autonomic failure (PAF), multiple system atrophy, Parkinson's disease, pure autonomic failure. Compensatory mechanisms preventing from decrease in blood pressure are inefficient in PAF. Among half of the patients with PAF occur orthostatic hypotension (OH) and supine hypertension (SH), which are the cause of deterioration of life quality. The treatment is based on modification of lifestyle and pharmacotherapy. Drugs used in OH may exacerbate SH and vice versa.

[Influence of subthalamic deep brain stimulation on dysautonomia observed in Parkinson's disease]. / Wplyw glebokiej stymulacji mózgowej jadra niskowzgórzowego na objawy autonomiczne obserwowane w chorobie Parkinsona.

Dysfunctions of the autonomic nervous system (DA) are common in Parkinson's disease (PD). DA appear in the premotor phase of PD and may antedate cardinal motor symptoms by years or decades. DA significantly impair quality of life in the majority of PD patients. DA are related to accumulation of Lewy bodies in the central and peripheral nervous system. Progression of neurodegeneration and chronic dopaminergic therapy may increase DA as well. It is accepted that bilateral deep brain stimulation of the subthalamic nucleus (STN DBS) improves motor symptoms in PD. The effect of STN DBS on DA, such as cardio-vascular symptoms and urinary, gastrointestinal and sexual dysfunction in PD, is not clear. STN DBS ameliorates some DA, but others might deteriorate at the same time.

Thalamic deep brain stimulation for tremor among multiple sclerosis patients.

BACKGROUND AND PURPOSE: Disabling tremor might be the main cause of disability of multiple sclerosis (MS) patients. Neuromodulation with deep brain stimulation of the thalamic nucleus ventralis intermedius (Vim DBS) is a well accepted method of neurosurgical treatment of tremor related to essential tremor or Parkinson disease. Vim DBS is not widely used to control MS tremor. MATERIAL AND METHODS: Five MS patients with tremor (3 females and 2 males) were treated with Vim DBS. Age at implantation was 37 ± 5 years. MS lasted from 5 to 12 years (mean 6) and tremor was the main cause of disability of those patients from 2 to 5 years (mean 3) before surgery. Clinical condition of the group was evaluated with spirography, the modified Fahn scale and the modified Activity of Daily Living (ADL) scale. Evaluations were performed before surgery and 3 months after surgery. MRI exclusion criteria were the presence of a thalamic hyperintense signal in T2-weight-ed images or ventricular enlargement. The procedures of implantation were performed under local and general anaesthesia. RESULTS: Intensity of contralateral limb tremor during intraoperative macrostimulation was reduced in the whole group. The therapeutic effect of DBS was maintained at three-month follow-up. Mean contralateral limb tremor reduction was 40%. Mean ADL score improved by 18%. No mortality or morbidity was reported in the group. CONCLUSIONS: The study confirms the value and safety of Vim DBS for treatment of MS-related tremor. Further study on a larger population and introduction of a qualification protocol might increase efficacy of the treatment.

Gliosarcoma Is Driven by Alterations in PI3K/Akt, RAS/MAPK Pathways and Characterized by Collagen Gene Expression Signature.

Gliosarcoma is a very rare brain tumor reported to be a variant of glioblastoma (GBM), IDH-wildtype. While differences in molecular and histological features between gliosarcoma and GBM were reported, detailed information on the genetic background of this tumor is lacking. We intend to fill in this knowledge gap by the complex analysis of somatic mutations, indels, copy number variations, translocations and gene expression patterns in gliosarcomas. Using next generation sequencing, we determined somatic mutations, copy number variations (CNVs) and translocations in 10 gliosarcomas. Six tumors have been further subjected to RNA sequencing analysis and gene expression patterns have been compared to those of GBMs. We demonstrate that gliosarcoma bears somatic alterations in gene coding for PI3K/Akt (PTEN, PI3K) and RAS/MAPK (NF1, BRAF) signaling pathways that are crucial for tumor growth. Interestingly, the frequency of PTEN alterations in gliosarcomas was much higher than in GBMs. Aberrations of PTEN were the most frequent and occurred in 70% of samples. We identified genes differentially expressed in gliosarcoma compared to GBM (including collagen signature) and confirmed a difference in the protein level by immunohistochemistry. We found several novel translocations (including translocations in the RABGEF1 gene) creating potentially unfavorable combinations. Collected results on genetic alterations and transcriptomic profiles offer new insights into gliosarcoma pathobiology, highlight differences in gliosarcoma and GBM genetic backgrounds and point out to distinct molecular cues for targeted treatment.

Cytokines in the pathogenesis of hemophilic arthropathy.

Hemophilic arthropathy (HA) is one of the most common and typical manifestation in the course of recurrent bleeding episodes in patients with hemophilia. Clinical and subclinical joint bleeding episodes gradually lead to irreversible changes manifesting themselves as pain, progressing ankylosis, marked limitation of the range of motion, muscle atrophy and osteoporosis commonly concomitant with joint deformity resulting from chronic proliferative synovitis and both cartilage and bone degeneration leading to the final functional impairment of the joint. In spite of numerous studies, the pathophysiology of HA has not been fully elucidated, especially as regards immunopathological mechanisms which are associated with the subclinical and early stage of the disease and to be more precise, with chronic joint inflammation. It needs to be emphasized that the pathophysiological processes occurring in a joint with HA are most probably highly mediated by interactions within the cytokine network and other inflammatory mediators present in the tissues of affected joint. Among numerous compounds participating in the induction of an inflammatory process in the pathogenesis of HA, cytokines seem to play a leading role. The most important group controlling the disease seems to be well known inflammatory cytokines, including IL-1ß, TNFα and IL-6. The second group with antagonistic effect is formed by anti-inflammatory cytokines such as IL-4 and IL-10. The role of inflammatory and anti-inflammatory cytokines in the pathogenesis of HA with respect to cellular and intracellular signaling pathways is still under investigation. This review, summarizes and discusses the current knowledge about cytokine network in the pathogenesis of HA, indicating possible molecular and cellular mechanisms that may provide potential new therapeutic directions.

Advanced reactive astrogliosis associated with hemangioblastoma versus astroglial-vascular neoplasm ("angioglioma").

Hemangioblastomas of the central nervous system are often accompanied by a cyst exhibiting an extensive astroglial reaction. The cyst's wall might be composed of various astroglial elements including reactive pilocytic or gemistocytic and hypertrophic astrocytes. The small tissue samples composed of compact gliotic tissue are sometimes nonrepresentative for primary hemangioblastoma tumour and might be confused with both pilocytic and diffuse infiltrative astrocytoma. Moreover, vascular anomalies of hemangioblastoma-like pattern could be combined with true neoplastic glial proliferation. Such association of glioma with certain types of vascular anomalies has been designated as angioglioma. In the current study we evaluated a series of hemangioblastomas accompanied by advanced astrogliosis of adjacent brain tissue. In some cases the histopathological features of pilocytic gliosis with numerous Rosenthal fibres and eosinophilic granular bodies strongly suggest the diagnosis of pilocytic astrocytoma. One tumour was identified as an angioglioma exhibiting a combination of hemangioblastoma-like tissue and pilocytic astrocytoma. The recognition of such an entity is important in differential tumour diagnosis and prognosis.

Thyroid hormones in the central nervous system (CNS) and their effect on neoplasm formation, particularly on the development and course of glioblastoma multiforme - research hypothesis.

The present study is aimed to present the potential role of thyroid hormones (TH) in the pathogenesis of glioblastoma multiforme (GBM). In first part of this presentation the effect of general homeostasis of TH on GBM formation and course was shown. Then the evidence concerning present state of the knowledge about active transport of TH to the brain, the role of iodothyronine deiodinase type 2 and 3 in the setting concentration of T3 in the brain and GBM cells, and finally knowledge about the role of genomic (TH nuclear receptors THRA and THRB) and non-genomic modes (membrane integrin receptor αvß3) of action of TH and its importance for GBM was outlined. The last part of this presentation was devoted to generally approved signalling pathways leading to the formation and the clinical course of GBM, showing at the same time evidence that each of the pathways is affected by particular TH actions. In conclusion it is suggested that TH is one of the pathogenetic factors for GBM and as such can have practical implications for the formation and course and treatment of this tumour.

Down-regulation of IKKß expression in glioma-infiltrating microglia/macrophages is associated with defective inflammatory/immune gene responses in glioblastoma.

Glioblastoma (GBM) is an aggressive malignancy associated with profound host immunosuppression. Microglia and macrophages infiltrating GBM acquire the pro-tumorigenic, M2 phenotype and support tumor invasion, proliferation, survival, angiogenesis and block immune responses both locally and systematically. Mechanisms responsible for immunological deficits in GBM patients are poorly understood. We analyzed immune/inflammatory gene expression in five datasets of low and high grade gliomas, and performed Gene Ontology and signaling pathway analyses to identify defective transcriptional responses. The expression of many immune/inflammatory response and TLR signaling pathway genes was reduced in high grade gliomas compared to low grade gliomas. In particular, we found the reduced expression of the IKBKB, a gene coding for IKKß, which phosphorylates IκB proteins and represents a convergence point for most signal transduction pathways leading to NFκB activation. The reduced IKBKB expression and IKKß levels in GBM tissues were demonstrated by qPCR, Western blotting and immunohistochemistry. The IKKß expression was down-regulated in microglia/macrophages infiltrating glioblastoma. NFκB activation, prominent in microglia/macrophages infiltrating low grade gliomas, was reduced in microglia/macrophages in glioblastoma tissues. Down-regulation of IKBKB expression and NFκB signaling in microglia/macrophages infiltrating glioblastoma correlates with defective expression of immune/inflammatory genes and M2 polarization that may result in the global impairment of anti-tumor immune responses in glioblastoma.