A Novel Approach for Glioblastoma Treatment by Combining Apoptosis Inducers (TMZ, MTX, and Cytarabine) with E.V.A. (Eltanexor, Venetoclax, and A1210477) Inhibiting XPO1, Bcl-2, and Mcl-1

Adjuvant treatment for Glioblastoma Grade 4 with Temozolomide (TMZ) inevitably fails due to therapeutic resistance, necessitating new approaches. Apoptosis induction in GB cells is inefficient, due to an excess of anti-apoptotic XPO1/Bcl-2-family proteins. We assessed TMZ, Methotrexate (MTX), and Cytarabine (Ara-C) (apoptosis inducers) combined with XPO1/Bcl-2/Mcl-1-inhibitors (apoptosis rescue) in GB cell lines and primary GB stem-like cells (GSCs). Using CellTiter-Glo® and Caspase-3 activity assays, we generated dose-response curves and analyzed the gene and protein regulation of anti-apoptotic proteins via PCR and Western blots. Optimal drug combinations were examined for their impact on the cell cycle and apoptosis induction via FACS analysis, paralleled by the assessment of potential toxicity in healthy mouse brain slices. Ara-C and MTX proved to be 150- to 10,000-fold more potent in inducing apoptosis than TMZ. In response to inhibitors Eltanexor (XPO1; E), Venetoclax (Bcl-2; V), and A1210477 (Mcl-1; A), genes encoding for the corresponding proteins were upregulated in a compensatory manner. TMZ, MTX, and Ara-C combined with E, V, and A evidenced highly lethal effects when combined. As no significant cell death induction in mouse brain slices was observed, we conclude that this drug combination is effective in vitro and expected to have low side effects in vivo.

Prostacyclin Released by Cancer-Associated Fibroblasts Promotes Immunosuppressive and Pro-Metastatic Macrophage Polarization in the Ovarian Cancer Microenvironment

Metastasis of high-grade ovarian carcinoma (HGSC) is orchestrated by soluble mediators of the tumor microenvironment. Here, we have used transcriptomic profiling to identify lipid-mediated signaling pathways encompassing 41 ligand-synthesizing enzymes and 23 cognate receptors in tumor, immune and stroma cells from HGSC metastases and ascites. Due to its strong association with a poor clinical outcome, prostacyclin (PGI₂) synthase (PTGIS) is of particular interest in this signaling network. PTGIS is highly expressed by cancer-associated fibroblasts (CAF), concomitant with elevated PGI₂ synthesis, whereas tumor-associated macrophages (TAM) exhibit the highest expression of its surface receptor (PTGIR). PTGIR activation by PGI₂ agonists triggered cAMP accumulation and induced a mixed-polarization macrophage phenotype with altered inflammatory gene expression, including CXCL10 and IL12A repression, as well as reduced phagocytic capability. Co-culture experiments provided further evidence for the interaction of CAF with macrophages via PGI₂, as the effect of PGI₂ agonists on phagocytosis was mitigated by cyclooxygenase inhibitors. Furthermore, conditioned medium from PGI₂-agonist-treated TAM promoted tumor adhesion to mesothelial cells and migration in a PTGIR-dependent manner, and PTGIR activation induced the expression of metastasis-associated and pro-angiogenic genes. Taken together, our study identifies a PGI₂/PTGIR-driven crosstalk between CAF, TAM and tumor cells, promoting immune suppression and a pro-metastatic environment.

Arachidonic acid, a clinically adverse mediator in the ovarian cancer microenvironment, impairs JAK-STAT signaling in macrophages by perturbing lipid raft structures

Survival of ovarian carcinoma is associated with the abundance of immunosuppressed CD163^highCD206^high tumor‐associated macrophages (TAMs) and high levels of arachidonic acid (AA) in the tumor microenvironment. Here, we show that both associations are functionally linked. Transcriptional profiling revealed that high CD163 and CD206/MRC1 expression in TAMs is strongly associated with an inhibition of cytokine‐triggered signaling, mirrored by an impaired transcriptional response to interferons and IL‐6 in monocyte‐derived macrophages by AA. This inhibition of pro‐inflammatory signaling is caused by dysfunctions of the cognate receptors, indicated by the inhibition of JAK1, JAK2, STAT1, and STAT3 phosphorylation, and by the displacement of the interferon receptor IFNAR1, STAT1 and other immune‐regulatory proteins from lipid rafts. AA exposure led to a dramatic accumulation of free AA in lipid rafts, which appears to be mechanistically crucial, as the inhibition of its incorporation into phospholipids did not affect the AA‐mediated interference with STAT1 phosphorylation. Inhibition of interferon‐triggered STAT1 phosphorylation by AA was reversed by water‐soluble cholesterol, known to prevent the perturbation of lipid raft structure by AA. These findings suggest that the pharmacologic restoration of lipid raft functions in TAMs may contribute to the development new therapeutic approaches.

Cell type-selective pathways and clinical associations of lysophosphatidic acid biosynthesis and signaling in the ovarian cancer microenvironment

The peritoneal fluid of ovarian carcinoma patients promotes cancer cell invasion and metastatic spread with lysophosphatidic acid (LPA) as a potentially crucial mediator. However, the origin of LPA in ascites and the clinical relevance of individual LPA species have not been addressed. Here, we show that the levels of multiple acyl‐LPA species are strongly elevated in ascites versus plasma and are associated with short relapse‐free survival. Data derived from transcriptome and secretome analyses of primary ascite‐derived cells indicate that (a) the major route of LPA synthesis is the consecutive action of a secretory phospholipase A₂ (PLA₂) and autotaxin, (b) that the components of this pathway are coordinately upregulated in ascites, and (c) that CD163+CD206+ tumor‐associated macrophages play an essential role as main producers of PLA₂G7 and autotaxin. The latter conclusion is consistent with mass spectrometry‐based metabolomic analyses of conditioned medium from ascites cells, which showed that tumor‐associated macrophages, but not tumor cells, are able to produce 20:4 acyl‐LPA in lipid‐free medium. Furthermore, our transcriptomic data revealed that LPA receptor (LPAR) genes are expressed in a clearly cell type‐selective manner: While tumor cells express predominantly LPAR1‐3, macrophages and T cells also express LPAR5 and LPAR6 at high levels, pointing to cell type‐selective LPA signaling pathways. RNA profiling identified cytokines linked to cell motility and migration as the most conspicuous class of LPA‐induced genes in macrophages, suggesting that LPA exerts protumorigenic properties at least in part via the tumor secretome.

Biosynthesis of 8-hydroxyquinoline-2-carboxylic acid, an iron chelator from the gut of the lepidopteran Spodoptera littoralis

In the regurgitate (foregut content) of Spodoptera larvae we found high concentrations (0.5-5 mM) of 8-hydroxyquinoline-2-carboxylic acid (8-HQA). In a survey of different lepidopteran species, this compound was only detected in species belonging to the family of Noctuidae. 8-HQA was shown to derive from tryptophan metabolism. The amount of 8-HQA in the regurgitate was strongly dependent on the tryptophan content of the diet. In the insect 8-HQA is generated from tryptophan via kynurenine and 3-hydroxykynurenine. 8-HQA is produced by the larvae and not by their commensal gut bacteria. Analysis of different life stages of Spodoptera larvae revealed that 8-HQA is formed during the larval stage, probably acting as an iron chelator to control the gut microbiome.

Structure and mechanism of iron translocation by a Dps protein from Microbacterium arborescens

Dps (DNA protection during starvation) enzymes are a major class of dodecameric proteins that bacteria use to detoxify their cytosol through the uptake of reactive iron species. In the stationary growth phase of bacteria, Dps enzymes are primarily used to protect DNA by biocrystallization. To characterize the wild type Dps protein from Microbacterium arborescens that displays additional catalytic functions (amide hydrolysis and synthesis), we determined the crystal structure to a resolution of 2.05 Å at low iron content. The structure shows a single iron at the ferroxidase center coordinated by an oxo atom, one water molecule, and three ligating residues. An iron-enriched protein structure was obtained at 2 Å and shows the stepwise uptake of two hexahydrated iron atoms moving along channels at the 3-fold axis before a restriction site inside the channels requires removal of the hydration sphere. Supporting biochemical data provide insight into the regulation of this acylamino acid hydrolase. Moreover, the peroxidase activity of the protein was determined. The influence of iron and siderophores on the expression of acylamino acid hydrolase was monitored during several stages of cell growth. Altogether our data provide an interesting view of an unusual Dps-like enzyme evolutionarily located apart from the large Dps sequence clusters.

[Neurological findings in patients treated surgically for spinal metastatic disease]

PURPOSE OF THE STUDY

We present a group of patients with spinal metastatic disease surgically treated at our department, with an evaluation of their neurological outcomes in relation to the initial disease and the surgical technique used.

MATERIAL

Between 1989 and 2007 we operated on 748 patients with spinal tumour. Of these, 380 had metastatic disease. The Frankel classification system was used to assess neurological status.

METHODS

Based on the Tomita prognostic score, the metastatic disease was evaluated and appropriate surgical procedure was selected (biopsy, posterolateral decompression, posterolateral decompression with stabilisation, somatectomy, or vertebrectomy/spondylectomy). The neurological findings before and after surgery and at follow-up were assessed.

RESULTS

Of the 368 patients evaluated, four were pre-operatively classified as Frankel grade A, 29 as grade B, 99 as grade C, 82 as grade D and 159 patients as grade E. Post-operative outcomes were: Frankel grade A, 6 patients B, 27 C, 78 D, 79 and E, 178 patients. Surgery resulted in neurological deterioration by 3 degrees of the Frankel scale in two patients (0.5%), 2 degrees in three patients (0.8%), and by 1 degree in 17 patients (4.6%). Improvement was recorded: by 1 degree in 57 patients (15.5%), 2 degrees in 10 (2,7%) and 3 degrees in two patients (0.5%). Of 23 patients who underwent biopsy, neurological status improved in one (4.3%) and deteriorated also in one patient (4.3%). Of the 85 patients treated by posterolateral decompression, improvement was recorded in 25 (29.4%) and deterioration in two (2.4%). Of the 73 patients undergoing posterolateral decompression with stabilisation, neurological findings improved in 15 (17.9%) and deteriorated in five (6.0%). In the group of 103 patients treated by vertebrectomy, neurological findings improved in 13 (12.6%) and deteriorated in eight (7.8%). At an average follow-up of 15 months, 208 (55.7%) patients presented themselves of these, improvement in neurological status was recorded in 16 (7.8%) and deterioration in eight (3.9%), as compared with the pre-operative values.

DISCUSSION

Any comparison with the literature data is difficult, because both the criteria of indication for surgery and the method of treatment differ considerably. Improvement in neurological status was achieved in 69 patients (18.8%).

CONCLUSIONS

Metastatic tumours of the spine present a serious diagnosis, with pain often being the first sign of a malignant disease. The degree of neurological deficit, primary tumour site and the extent of metastatic spinal disease (objectively evaluated on the basis of the Tomita score) should determine whether the patient will be operated on or not and, if so, whether a radical or mere palliative procedure will be used. An important factor is multidisciplinary cooperation of attending physicians both preoperatively and during the post-operative care of cancer patients.

[Simple bony fusion or instrumented hemivertebra excision in the surgical treatment of congenital scoliosis]

PURPOSE OF THE STUDY

In a retrospective study, to analyze long-term radiographic results of two surgical procedures used to treat congenital scoliosis.

MATERIAL AND METHODS

A total of 685 patients with congenital scoliosis were treated at the Department of Orthopaedic Surgery, Bohunice Teaching Hospital in Brno, between 1976 and 2007. Of these, 102 patients, with an average age of 6.6 years at the time of surgery, were treated by simple bony fusion, and 22 children, with an average age of 10.2 years, underwent instrumented hemivertebra excision via simultaneous anterior and posterior exposures involving fixation with cannulated compression screws and a wire loop. The follow-up periods for the former and latter groups were 14.2 and 12.1 years, respectively.

RESULTS

In the patients treated by simple bony fusion, the mean correction rate was 22.1 %, with Cobb angle values averaging from 44.2 degrees pre-operatively to 38 degrees post-operatively; the correction loss was 3.9 degrees at the last follow up. In the patients with hemivertebra excision, the mean correction rate was 61 %, with pre- and post-operative values of 51.3 degrees and 20.3 degrees , respectively, and a correction loss of 1.1 degrees at the last follow-up.

DISCUSSION

The early detection of a deformity and simple bony fusion in low-magnitude curves can prevent progression of scoliosis and allows for maintenance of a compensated spine. Hemivertebra excision with compression instrumentation results in a better surgical correction of the deformity. The average 61 % correction rate achieved in our patients is in agreement with the results reported by authors using the same surgical technique, as well as with the results of posterior hemivertebra resection. The best correction, 78 %, has been achieved with surgery at a very young age. Complications associated with the two techniques are rare.

CONCLUSIONS

Congenital scoliosis due to failure off either formation or segmentation is indicated for surgical treatment at young age. Its early detection and subsequent surgical treatment at young age. Its early detection and subsequent surgical correction of the curve result in a long-term maintenance of a compensated spine. Instrumented hemivertebra excision provides the highest rate of correction, particularly if carried out before 3 years of age.

Some trace elements in coal of the Czech Republic, environment and health protection implications

Mining for coal and its utilization have various impacts on the surrounding environment. Huge volumes of waste materials which are by-products of both the underground and open cast coal mining, pose one of the major environmental hazards in addition to air pollution caused by coal burning in power plants in the Czech Republic. Some of these risks could be reduced when having accurate and comprehensive data on coal quality. Statistical data processing of almost 35,000 coal samples from Late Paleozoic and Tertiary coal basins of the Czech Republic provided a unique information on the quality of lignite, sub-bituminous and bituminous coals and anthracites including the content of toxic trace elements (As, Be, Hg, Pb and Se). In this context related environment and health risks and protection implications are discussed.

Ginger: an ethnomedical, chemical and pharmacological review

Powerful medicinal properties have been recorded for Zingiber officinale, commonly known as ginger. All of these medicinal activities have been compiled with 99 references to the present status of the plant in the literature. Volatile components and the presence of trace metals are included. In addition, details of individual medicinal activities are given and the molecular structures of identified organic metabolites and their synthesis are described.

[Mathematical models in epizootiology]

Mathematical modelling in epizootology makes it possible to forecast the occurrence and spreading of infection, to learn the main factors of the origin and spread of infection, or to test hypotheses on these factors. Therefore epizootological models must be correct from the biological and mathematical view-point. They should not contradict to experimental facts, must be sufficiently sensitive to important factors, and must be able to approximate real epizootological phenomena and processes. Examples of the construction of simple deterministic and stochastic models of exogenous infections whose etiological agents meet the conditions of Henle-Koch's postulates are used for demonstrating the basic approaches to the use of mathematical models for the evaluation of epizootological analyses and programmes of infection control.

Rotavirus gastroenteritis in infants and young children

The electronmicroscopic examination of stool samples from 18 infants and young children with gastroenteritis, hospitalized at the Clinic of Infectious Diseases in Prague, was carried out. In ten children rotavirus was found in the faeces and the bacteriological findings were negative. Rotavirus particles were aggregated by convalescent child sera and by normal human gamma globulin. The clinical picture was characterized by the sudden onset of vomiting and fever, in one case with febrile convulsions. Diarrhoea was watery and yellow-green, and usually persisted for four to five days. The condition of the children improved rapidly after rehydration and a special diet. Older siblings, and in one family also adult members, were frequently affected.

Estimation of genotypic and environmental variation in plants

The frequency of genotypes with the desired degree of expression of economically important quantitative characters within a hybrid or mutant population is usually very low. Therefore, the early identification and selection of such genotypes involves the analysis of very large populations. Because the breeding values of individuals in a population are masked by environmental, competitional, and ontogenic noises, special quantitative--genetic methods of analysis have to be used in order to eliminate their disturbing effects. The present chapter deals with a new approach to such an analysis by using either a simple background character or a background index obtained as a linear function of two, or more than two, background characters. It is believed that the use of this approach would greatly increase the efficiency of selection and shorten the time needed to produce improved new crop cultivars. As the analyses require the handling of large amounts of measurement data, plant breeders must use computer facilities.