Development of DNA Aptamers for Visualization of Glial Brain Tumors and Detection of Circulating Tumor Cells

Here, we present DNA aptamers capable of specific binding to glial tumor cells in vitro, ex vivo, and in vivo for visualization diagnostics of central nervous system tumors. We selected the aptamers binding specifically to the postoperative human glial primary tumors and not to the healthy brain cells and meningioma, using a modified process of systematic evolution of ligands by exponential enrichment to cells; sequenced and analyzed ssDNA pools using bioinformatic tools and identified the best aptamers by their binding abilities; determined three-dimensional structures of lead aptamers (Gli-55 and Gli-233) with small-angle X-ray scattering and molecular modeling; isolated and identified molecular target proteins of the aptamers by mass spectrometry; the potential binding sites of Gli-233 to the target protein and the role of post-translational modifications were verified by molecular dynamics simulations. The anti-glioma aptamers Gli-233 and Gli-55 were used to detect circulating tumor cells in liquid biopsies. These aptamers were used for in situ, ex vivo tissue staining, histopathological analyses, and fluorescence-guided tumor and PET/CT tumor visualization in mice with xenotransplanted human astrocytoma. The aptamers did not show in vivo toxicity in the preclinical animal study. This study demonstrates the potential applications of aptamers for precise diagnostics and fluorescence-guided surgery of brain tumors.

[The Evaluation of Medical Demographic and Economic Losses of the Region Conditioned by Mortality of Lung Cancer]

The article presents evaluation of medical demographic and economic losses of population of the Krasnoyarskii kraii conditioned by mortality of lung cancer in 2010-2014 using DALY technology. In the Krasnoyarskii kraii, during 2010-2014 64,712 individuals died because of lung cancer. The mortality of male population surpasses corresponding indices of mortality of females up to 3.9 times. In the region, the standardized indicator mortality of lung cancer among males annually surpasses the same indicator among females at maximum up to 8.1 times. The DALY maximal absolute losses of among males were registered in 2010 and 2013 and fell on age group of 55-59 years and among females on the age group of 60-64 years in 2014. The maximal (up to 5.2 times) difference in values of DALY indicator was established in 2010 between male and female population. the maximal gap in in DALY indices between male and female population was established in the age of 55-59 years. Almost half of DALY losses among males was established in 2013 and among females in 2014. The total losses of gross regional product in the region because of mortality conditioned by lung cancer made up to 29.8 billions of rubles in 2010-2014.

DNA Aptamers for the Characterization of Histological Structure of Lung Adenocarcinoma

Nucleic acid aptamers are becoming popular as molecular probes for identification and imaging pathology and, at the same time, as a convenient platform for targeted therapy. Recent studies have shown that aptamers may be effectively used for tumor characterization and as commercially available monoclonal antibodies. Here we present three DNA aptamers binding to whole transformed lung cancer tissues, including tumor cells, connective tissues, and blood vessels. Protein targets have been revealed using affinity purification followed by mass spectrometry analyses, and they have been validated using a panel of correspondent antibodies and 3D imaging of tumor tissues. Each of the proteins targeted by the aptamers is involved in cancer progression and most of them are crucial for lung adenocarcinoma. We propose the use of these aptamers in aptahistochemistry for the characterization of the histological structure of lung adenocarcinoma. The value of the presented aptamers is their application together or separately for indicating the spread of neoplastic transformation, for complex differential diagnostics, and for targeted therapy of the tumor itself as well as all transformed structures of the adjacent tissues. Moreover, it has been demonstrated that these aptamers could be used for intraoperative tumor visualization and margin assessment.

Electrochemical aptasensor for lung cancer-related protein detection in crude blood plasma samples

The development of an aptamer-based electrochemical sensor for lung cancer detection is presented in this work. A highly specific DNA-aptamer, LC-18, selected to postoperative lung cancer tissues was immobilized onto a gold microelectrode and electrochemical measurements were performed in a solution containing the redox marker ferrocyanide/ferricyanide. The aptamer protein targets were harvested from blood plasma of lung cancer patients by using streptavidin paramagnetic beads and square wave voltammetry of the samples was performed at various concentrations. In order to enhance the sensitivity of the aptasensor, silica-coated iron oxide magnetic beads grafted with hydrophobic C8 and C4 alkyl groups were used in a sandwich detection approach. Addition of hydrophobic beads increased the detection limit by 100 times. The detection limit of the LC-18 aptasensor was enhanced by the beads to 0.023 ng/mL. The formation of the aptamer – protein – bead sandwich on the electrode surface was visualized by electron microcopy. As a result, the electrochemical aptasensor was able to detect cancer-related targets in crude blood plasma of lung cancer patients.

Cancer incidence in the Krasnoyarsk Krai

The paper is devoted to the study of the incidence of malignant tumors in the Krasnoyarsk Krai throughout 2005-2014. The greatest increase in incidence in the region during the study period - 58.5% was determined in women. There was established the gain in the incidence in the region by 39.5%, as well as there was revealed the advancement on leading localizations. On the basis of established trends there was made calculation for medium-term forecast of the morbidity rate in the region. By 2020, there is expected the gain in the incidence in the Krai by 1.5 times: breast cancer - by 17%, skin cancer - by 22%, lung cancer - by 21.6%, prostate cancer - by 19.6%; for gastric cancer incidence rate will decrease by 5.9%.

[The children health centers: first results of functioning and perspectives of development]

The article presents analysis of functioning of children health centers organized in allsubjects of the Russian Federation. For the first time, according data of report form 68, the information are received concerning visits of children in following age groups: 0-4 years, 5-9 years, 10-14 years, 15 and 16-17 years. The average Russian indicators of visits of children health centers are calculated that can be applied in territories as markers of their effectiveness. The main flows of arrival of children population to health centers and determining factors are established. The particular attention is paid to analysis of repeated visits. The regional experience of their payments in the system of mandatory medical insurance is presented. The experience of implementation of Internet resources in propaganda of healthy life-style in adolescents and young parents is examined. The results of the carried out study were used as a basis to establish in n prevention activities of children health centers problem zones of medical organizational, technological and informational character. The proposals are given concerning enhancement of children health centers functioning.