Plasma osteopontin in comparison with bone markers as an indicator of distant metastases and a predictor of survival outcome in prostate cancer and renal cell carcinoma patients

DissertationOsteopontin (OPN) is a glycoprotein, which is present in all body fluids including plasma. Due to the presence of arginine-glycine-aspartic acid sequence (RGD) in its structure OPN is capable of binding to cell integrin receptors and promoting adhesion, proliferation, and survival in various cell types including tumor cells. Its involvement in tumor progression and metastasis has been indicated in a number of studies. For example, tumor cells with high invasive properties or obtained from metastatic lesions show elevated OPN expression and, moreover, OPN expression in tissue correlates with tumor stage and size as well as survival of cancer patients. All these findings suggest that elevation of OPN levels in blood could also reflect tumor progression towards metastasis and poor prognosis for cancer patients. In addition, OPN is abundantly distributed in bone tissue and involved in the regulation of bone turnover. This indicates that OPN in plasma could also be a sensitive indicator of skeletal metastasis, since the latter alters finely balanced processes of bone turnover. The PubMed literature review has shown that reports on plasma OPN in prostate cancer (PCa) are very limited whereas in renal cell carcinoma (RCC) no studies have been done so far. Therefore, the aim of this study was to evaluate the clinical usefulness of plasma OPN in patients suffering from PCa and RCC. Diagnostic and prognostic significance of plasma OPN was compared with the established bone formation markers: N-terminal propeptide of type I procollagen (PINP), bone-specific alkaline phosphatase (bALP) and the bone resorption marker: cross-linked carboxyterminal telopeptide of type I collagen (ICTP). Prostate cancer. This study included 90 patients with PCa, 35 patients with benign prostatic hyperplasia (BPH) and 29 healthy men. Plasma OPN and bone markers were significantly elevated in PCa patients with bone metastases compared to those without bone metastases, BPH group, and controls (P<0.05 at least). OPN and bone markers were effective in the detection of bone metastases with AUC ranged from 0.80 to 0.88 (all P<0.0001). There were no significant differences between ROC curves of OPN and bone markers. However, at the cutoff level of 95% sensitivity, specificity of OPN outperformed that of bALP and PINP (P=0.0266 and 0.0009, McNemar test). Only OPN and bALP in the multivariate binary logistic model retained significant predictive value in relation to bone metastasis in PCa patients (P=0.011 and 0.001). Combination of these two markers using logistic regression approach in order to enhance the diagnostic accuracy in the detection of bone metastases led to a distinct increase in AUC up to 0.93 compared to OPN (AUC, 0.85; P=0.026) and bALP (AUC, 0.88; P=0.008). At the cutoff with 95% sensitivity, the specificity of OPN and bALP in combination amounted to 63% and was greater than that for OPN (31%) and bALP (11%). OPN correlated closely with the bone markers (rs=0.43-0.79, all P<0.05) and with tumor grade (rs=0.23, P<0.05). OPN and all bone markers were associated with survival (Kaplan-Meier, P<0.0001). PCa patients with high concentration of biochemical markers had shorter survival time than those with lower concentrations of biochemical markers. OPN and PINP were identified in multivariate Cox regression model as independent predictors of survival outcome in PCa patients. Renal cell carcinoma. This study included 80 patients with RCC and 52 controls. Compared to controls plasma OPN and ICTP were elevated in patients with distant bone and non-bone metastases (P<0.05 at least). Moreover, plasma OPN was also elevated in RCC patients with distant metastases compared to those with organ-confined disease (P<0.05 at least). OPN and ICTP were examined in ROC analysis in relation to distant metastases. ROC curve of OPN (AUC, 0.89) was larger than that of ICTP (AUC, 0.71, P=0.018). At the cutoff with 95 % sensitivity, the specificity of OPN (57%) outperformed (McNemar test, P=0.0309) that of ICTP (25%). OPN correlated closely with the bone markers (rs=0.37-0.50, all P<0.05). Significant correlation was also observed between OPN and tumor stage (rs=0.50, P<0.01) and grade (rs=0.33, P<0.05). Levels of OPN and ICTP were associated with survival (Kaplan-Meier, P<0.0001). Patients with high concentrations of these two markers had shorter survival time than those with lower concentrations of OPN and ICTP. Logistic regression model determined OPN as a significant independent variable with predictive value related to distant metastasis in RCC patients (P=0.004). OPN was identified in Cox regression model as an independent factor related to the survival outcome in patients with RCC (P=0.041). In conclusion, plasma OPN is an effective marker in the detection of bone metastases in PCa patients. Moreover, combination of OPN with bALP significantly enhances diagnostic accuracy in relation to bone metastases. In RCC patients plasma OPN is useful in the diagnosis of distant bone and non- bone metastases and reflects tumor progression. In addition, evaluation of OPN in plasma has prognostic significance for both PCa and RCC patients.Osteopontin (OPN) ist ein Glycoprotein, das in allen menschlichen Flüssigkeiten einschließlich Plasma vorkommt. Auf Grund der Arginin-Glycin- Asparaginsäure- Sequenz (RGD) in der Struktur des OPN-Proteins ist dieses fähig, sich an die Integrin-Rezeptoren der Zellen zu binden. Dadurch werden Adhäsion, Proliferation und das Überleben von verschiedenen Zellen, auch Tumorzellen positiv beeinflusst. Die Bedeutung des OPN-Proteins hinsichtlich Tumorprogression und Metastasierung wurde in zahlreichen Studien bewiesen. In invasiven Tumorzellen oder Tumorzellen aus Metastasen fanden sich erhöhte Mengen von OPN. Die OPN-Expression im Tumorgewebe korreliert mit Tumorstadium und Tumorgröße sowie mit der Überlebenszeit der Patienten. Alle diese Ergebnisse deuten darauf hin, dass ein Anstieg von OPN im Plasma die Tumorprogression zur Metastasierung und damit eine schlechte Prognose für den Patienten anzeigt. Durch das reichliche Vorkommen von OPN im Knochen und seiner Bedeutung für Regulierung beim Knochenumsatz, könnte ein erhöhter OPN- Wert im Plasma ein sensitiver Indikator der Knochenmetastasierung sein. Eine eigene PubMed-Literaturrecherche ergab nur wenige Publikationen über das Verhalten des Plasma-OPN bei Patienten mit einem Prostatakarzinom (PCa). Bei Patienten mit einem Nierenzellkarzinom (RCC) war dies bisher kein Gegenstand von Untersuchungen. Deshalb war das Ziel der Studie, die klinische Aussagekraft von Plasma-OPN bei PCa- und RCC-Patienten zu ermitteln. Die diagnostische und prognostische Bedeutung von Plasma-OPN wurde mit Markern des Knochenaufbaus, dem N-terminalen Propeptid vom Typ I Prokollagen (PINP) und der knochenspezifischen alkalischen Phosphatase (bALP) sowie mit dem Knochenabbaumarker, dem quervernetzten, karboxyterminalen Telopeptid vom Typ I Prokollagen (ICTP), verglichen. Prostatakarzinom. Diese Studie umfasste 90 PCa-Patienten, 35 Patienten mit benigner Prostatahyperplasie (BPH) und 29 gesunde Männer. OPN und die Knochenmarker waren im Plasma von Patienten mit Knochen-Metastasen im Vergleich zu denen ohne Knochen-Metastasen, zu BPH- Patienten und Gesunden wesentlich erhöht (P<0.05 mindestens). Knochenmetastasen wurden bei den Patienten durch die Knochenszintigraphie sowie weitere Untersuchungen gesichert. OPN und Knochenmarker wiesen in der receiver operation characteristic-(ROC)-Analyse eine gute Diskrimination zwischen Patienten mit und ohne Knochenmetastasen auf. Die Flächen unter den ROC-Kurven (AUC) lagen zwischen 0.80 bis 0.88 (alle P-Werte <0.0001). Es gab keine entscheidenden Unterschiede zwischen den AUCs der ROC-Kurven von OPN und Knochenmarkern. Jedoch war beim Diskriminationspunkt von 95% Sensitivität die Spezifität von OPN höher als die Spezifität von bALP und PINP (P=0.026 und 0.0009, McNemar Test). OPN und bALP waren in der multivariaten Auswertung mit der binären logistischen Regression signifikant unabhhängige Diskriminatoren in Bezug auf die Erfassung einer Knochenmetastasierung. Die Kombination dieser beiden Marker mit Hilfe der logistischer Regression ergab einen signifikant höheren AUC-Wert als für die Einzelmarker (AUC von 0.93 im Vergleich zu OPN mit AUC, 0.85; P=0.026 bzw. zu bALP mit AUC, 0.88; P=0.008). Beim Diskriminationspunkt von 95% Sensitivität erreichte die Kombination von OPN und bALP eine Spezifität von 63%. Diese war höher als die Spezifität von OPN (31%) und bALP (11%) für sich genommen. Es gab eine signifikant positive Korrelation von OPN zu den Knochenmarkern (rs=0.43-0.79, alle P-Werte <0.05) und zum Tumorgrad (rs=0.23, P<0.05). Die Konzentrationen von OPN und Knochenmarkern im Blut korrelierten negativ mit der Überlebenszeit der Patienten (Kaplan-Meier, P<0.0001). Je höher die Markerkonzentration, desto kürzer war die Überlebenszeit. OPN und PINP wurden mit Hilfe der multivariaten Cox-Regression als signifikante Indikatoren hinsichtlich Überlebenszeit von PCa-Patienten ermittelt. Nierenzellkarzinom. Diese Studie umfasste 80 RCC- Patienten mit lokal begrenztem Tumor, mit Lymphknotenmetastasen bzw. Fernmetastasen sowie 52 gesunde Frauen und Männer als Kontrollgruppe. Im Vergleich zur Kontrollgruppe waren OPN und ICTP bei Patienten mit Fernmetastasen in Knochen und in anderen Organen (P<0.05 mindestens) erhöht. Erhöhte OPN-Werte wurden außerdem bei Patienten mit Fernmetastasen im Vergleich zu RCC-Patienten ohne Metastasen beobachtet (P<0.05 mindestens). Die Beziehung von OPN und ICTP bei Patienten mit Fernmetastasen wurde weiter mit der ROC-Analyse untersucht. Der AUC-Wert für OPN (0.89) war größer als der für ICTP (AUC, 0.71, P=0.018). Beim Diskriminationspunkt von 95% Sensitivität betrug die Spezifität für OPN 57%, die für ICTP lediglich 25% (McNemar Test, P=0.0309). OPN zeigte signifikante Korrelationen mit Knochenmarkern (rs=0.37-0.50, alle P Werte <0.05). Die OPN-Konzentration korrelierte mit dem Tumorstadium (rs=0.50, P<0.01) und Tumorgrad (rs=0.33, P<0.05). Konzentrationen von OPN und ICTP wurden außerdem mit der Überlebenszeit von RCC-Patienten assoziiert (Kaplan-Meier, P<0.0001). In der multivariaten Cox- Regression erwies sich OPN als allein signifikanter Faktor hinsichtlich Überlebenszeit (P=0.041). Die wesentliche Schlussfolgerung aus den hier vorgestellten Untersuchungen besteht darin, dass OPN im Plasma bei Patienten mit Prostatakarzinom und Nierenzellkarzinom als Metastasierungs- und Prognosemarker hinsichtlich des Überlebens eingesetzt werden kann. Die Daten belegen, dass die Durchführung einer prospektiven multizentrischen Studie, die auch andere z.Z. diskutierte neue Marker wie z.B. YKL-40 mit einschließen sollte, im Sinne der evidenzbasierten Medizin gerechtfertigt ist

Assessment of the microbial communities and their petroleum hydrocarbon transformation potential in the northern Caspian sea

Marine bacterial biodiversity is an immense library of tools which have a potential in bioremediation of oil spills [1]. Oil industry is flourishing in the Caspian Sea which is effecting local environment and we hypothesize that natural seeps and historical anthropogenic leaks have sustained indigenous microbial communities, including hydrocarbon-oxidizing microorganisms (Picture 1). Indigenous microbial communities of Northern part of the Sea and their overall metabolic potential have not been studied comprehensively. We aim to gain knowledge about the bacterial community, determine specific hydrocarbon degrading species and study their potential in bioremediation of oil-polluted Caspian Sea waters

Draft Genome Sequence of Lactobacillus salivarius KZ-NCB, Isolated from Chicken Cecum

Here, we report the draft genome sequence of Lactobacillus salivarius strain KZ-NCB, which was isolated from the cecum of a healthy chicken from a poultry farm in Kazakhstan.Peer reviewe

In search of suitable reference genes for gene expression studies of human renal cell carcinoma by real-time PCR

<p>Abstract</p> <p>Background</p> <p>Housekeeping genes are commonly used as endogenous reference genes for the relative quantification of target genes in gene expression studies. No conclusive systematic study comparing the suitability of different candidate reference genes in clear cell renal cell carcinoma has been published to date. To remedy this situation, 10 housekeeping genes for normalizing purposes of RT-PCR measurements already recommended in various studies were examined with regard to their usefulness as reference genes.</p> <p>Results</p> <p>The expression of the potential reference genes was examined in matched malignant and non-malignant tissue specimens from 25 patients with clear cell renal cell carcinoma. Quality assessment of isolated RNA performed with a 2100 Agilent Bioanalyzer showed a mean RNA integrity number of 8.7 for all samples. The between-run variations related to the crossing points of PCR reactions of a control material ranged from 0.17% to 0.38%. The expression of all genes did not depend on age, sex, and tumour stage. Except the genes TATA box binding protein (<it>TBP</it>) and peptidylprolyl isomerase A (<it>PPIA</it>), all genes showed significant differences in expression between malignant and non-malignant pairs. The expression stability of the candidate reference genes was additionally controlled using the software programs geNorm and NormFinder. <it>TBP </it>and <it>PPIA </it>were validated as suitable reference genes by normalizing the target gene <it>ADAM9 </it>using these two most stably expressed genes in comparison with up- and down-regulated housekeeping genes of the panel.</p> <p>Conclusion</p> <p>Our study demonstrated the suitability of the two housekeeping genes <it>PPIA </it>and <it>TBP </it>as endogenous reference genes when comparing malignant tissue samples with adjacent normal tissue samples from clear cell renal cell carcinoma. Both genes are recommended as reference genes for relative gene quantification in gene profiling studies either as single gene or preferably in combination.</p

Trends in the legal labour reform policy in the Kyrgyz Republic

The article is concerned with the analysis of the transformations in the labour market taking place in the Kyrgyz Republic (KR), which cause a great resonance in society, but continue to remain unexplored in the legal literature. Consequently, the purpose of the article is to identify the general trend in the legal labour reform policy and to determine the main directions of legal policy to improve the mechanism of legal regulation of labor. In the article, the objectives of classifying the main periods of the implementation of labor reforms (begun in 2005) are solved, analysis and assessment of the means of implementing reforms in terms of their compliance with national and international labor standards are carried out based on dialectical and logical methods, as well as the use of the systemic method. The article reveals serious inconsistencies between the deregulation policy and prohibitions in the labour market with the ILO Conventions No. 81, 87, 150, 155, which were ratified by the Kyrgyz Republic (except for the ILO Convention No. 155). In particular, the negative consequences of the deregulation policy for the field of labor safety and protection were noted, especially in the context of the onset of the COVID-19 coronavirus. Based on the analysis of the problems of the labor regulation reform policy, it is concluded that it is necessary to develop a unified state program for the development of the labour market, containing a system of strategic priorities, conceptual ideas, goals and measures that determine the prospects for improving the labor legislation of the Kyrgyz Republic on the basis of intensifying the processes of monitoring labor legislation and the practice of its enforcement in the Kyrgyz Republic. The provisions and conclusions of this article are of practical importance for the executive authorities implementing state policy in the field of labor

Genetic diversity of Francisella tularensis subsp. holarctica in Kazakhstan

Tularemia is a highly dangerous zoonotic infection due to the bacteria Francisella tularensis. Low genetic diversity promoted the use of polymorphic tandem repeats (MLVA) as first-line assay for genetic description. Whole genome sequencing (WGS) is becoming increasingly accessible, opening the perspective of a time when WGS might become the universal genotyping assay. The main goal of this study was to describe F. tularensis strains circulating in Kazakhstan based on WGS data and develop a MLVA assay compatible with in vitro and in silico analysis. In vitro MLVA genotyping and WGS were performed for the vaccine strain and for 38 strains isolated in Kazakhstan from natural water bodies, ticks, rodents, carnivores, and from one migratory bird, an Isabellina wheatear captured in a rodent burrow. The two genotyping approaches were congruent and allowed to attribute all strains to two F. tularensis holarctica lineages, B.4 and B.12. The seven tandem repeats polymorphic in the investigated strain collection could be typed in a single multiplex PCR assay. Identical MLVA genotypes were produced by in vitro and in silico analysis, demonstrating full compatibility between the two approaches. The strains from Kazakhstan were compared to all publicly available WGS data of worldwide origin by whole genome SNP (wgSNP) analysis. Genotypes differing at a single SNP position were collected within a time interval of more than fifty years, from locations separated from each other by more than one thousand kilometers, supporting a role for migratory birds in the worldwide spread of the bacteria.Peer reviewe

MACROPOROUS CELL-LADEN GELATIN/HYALURONIC ACID/CHONDROITIN SULFATE CRYOGELS FOR ENGINEERED TISSUE CONSTRUCTS

Cryogels are a unique macroporous material for tissue engineering. In this work, we study the effect of hyaluronic acid on the physicochemical properties of cryogel as well as on the proliferation of a 3D model of mesenchymal stem cells. The functional groups of the synthesized cryogels were identified using Fourier transform infrared spectroscopy. With an increase in the content of hyaluronic acid in the composition of the cryogel, an increase in porosity, gel content and swelling behavior was observed. As the hyaluronic acid content increased, the average pore size increased and more open pores were formed. Degradation studies have shown that all cryogels were resistant to PBS solution for 8 weeks. Cytotoxicity assays demonstrated no toxic effect on viability of rat adipose-derived mesenchymal stem cells (ADMSCs) cultured on cryogels. ADMSC spheroids were proliferated on scaffolds and showed the ability of the cryogels to orient cell differentiation into chondrogenic lineage even in the absence of inductive agents. Thus, our results demonstrate an effective resemblance to extracellular matrix structures specific to cartilage-like microenvironments by cryogels and their further perspective application as potential biomaterials

Use of information and computer models in the process of training future teachers of physics

In article methodical aspects of use of information and computer models in the course of training of future teachers of physics are analyzed. The attention is focused on expediency of development of new means of informatization of training of students of higher education institutions to physics

MHC class I chain-related protein A shedding in chronic HIV-1 infection is associated with profound NK cell dysfunction

Natural killer (NK) cells play a critical role in host defense against viral infections. However chronic HIV-1 infection is associated with an accumulation of dysfunctional NK cells, that poorly control viral replication. The underlying mechanisms for this NK cell mediated dysfunction are not understood. Certain tumors evade NK cell mediated detection by dampening NK cell activity through the downregulation of NKG2D, via the release of soluble NKG2D-ligands, resulting in a potent suppression of NK cell function. Here we show that chronic HIV-1 infection is associated with a specific defect in NKG2D-mediated NK cell activation, due to reduced expression and transcription of NKG2D. Reduced NKG2D expression was associated with elevated levels of the soluble form of the NKG2D-ligand, MICA, in patient sera, likely released by HIV+CD4+ T cells. Thus, like tumors, HIV-1 may indirectly suppress NK cell recognition of HIV-1-infected CD4+ T cells by enhancing NKG2D-ligand secretion into the serum resulting in a profound impairment of NK cell function