[Covalently conjugated DNA aptamer with doxorubicin as in vitro model for effective targeted drug delivery to human glioblastoma tumor cells]. / Kovalentno kon"yugirovannyi DNK-aptamer s doksorubitsinom kak in vitro model' effektivnogo adresnogo vozdeistviya na opukholevye kletki glioblastomy cheloveka.

Targeted delivery of chemotherapeutic agents with aptamers is a very effective method increasing therapeutic index compared to non-targeted drugs. OBJECTIVE: To study the effectiveness of in vitro therapeutic effect of covalently conjugated GR20 DNA aptamer with doxorubicin on glioblastoma cells compared to reference culture of human fibroblasts. MATERIAL AND METHODS: A Sus/fP2 cell culture was obtained from glioblastoma tissue sample to analyze the effectiveness of conjugate. A linear culture of human dermal fibroblasts (mesenchymal stem cells) DF1 was used as a control. To assess antiproliferative activity of covalently conjugated GR20 aptamer with doxorubicin, we used the MTS test. The Cell Index was measured using the xCelligence S16 cell analyzer assessing viability of cell cultures by recording changes in real time. RESULTS: Human glioblastoma Sus/fP2 cells reduce own proliferative potential by 80% when exposed to doxorubicin (0.5 µM, 72 hours, MTS test), by 9% when exposed to GR20 aptamer (10 µM, 72 hours, MTS test) and by 26% when exposed to covalently conjugated DOX-GR20 (0.5 µM, 72 hours, MTS test). A long-term study of proliferative potential of Sus/fP2 cells on the xCelligence S16 analyzer revealed a significant decrease in the number of cells under the effect of doxorubicin and covalently conjugated DOX-GR20. Effectiveness of covalently conjugated DOX-GR20 is halved. GR20 aptamer at a concentration of 10 µM and its conjugate with doxorubicin DOX-GR20 at a concentration of 1 µM have no negative effect on cells of the control culture of DF1 fibroblasts, while doxorubicin is toxic for these cells. MTS test and xCelligence S16 cell analyzer found no decrease in metabolic activity of DF1 cells and their ability to proliferate. CONCLUSION: We established obvious antiproliferative effect of covalent conjugate DOX-GR20 on continuous human glioblastoma cell culture Sus/fP2 without toxic effect on the reference culture (dermal fibroblasts DF1).

[Prognostic model for assessing the human glioma cell malignancy grade based on MDM2, MELK, SOX2, CDK4, DR5 and OCT4 gene expression]. / Prognosticheskaya model' dlya otsenki stepeni zlokachestvennosti kul'tury kletok gliomy cheloveka na osnovanii issledovaniya ekspressii paneli genov MDM2, MELK, SOX2, CDK4, DR5 i OCT4.

Glioma cell cultures are used in basic researches of tumor processes, personalized medicine for selecting treatment regimens depending on individual characteristics of patients and pharmacology for assessing the effectiveness of chemotherapy. Suppression of glioma culture growth without reduction of malignancy grade is common. Drug cancellation may be followed by substitution of precursor cells by more malignant clones. Therefore, analysis of culture cell malignancy grade is important. In the future, intraoperative analysis of glioma cell malignancy grade can be used to select individual therapy. OBJECTIVE: We analyzed the relationship between expression of marker genes TUBB3, CD133, CDK4, CDK6, CIRBP, DR4, DR5, EGFR, FGFR, FSHR, GDNF, GFAP, L1CAM, LEF1, MAP2, MDM2, MELK, NANOG, NOTCH2, OCT4, OLIG2, PDGFRA, PDGFA, PDGFB and SOX2 and glioma cell malignancy grade, as well as created appropriate prognostic model. MATERIAL AND METHODS: We analyzed expression of 25 marker genes in 22 samples of human glioma cultures using quantitative real-time PCR. Statistical analysis was performed using the IBM SPSS Statistics 26.0 software. We used the Kolmogorov-Smirnov and Shapiro-Wilk tests to assess distribution normality. Nonparametric Jonckheere-Terpstra and Spearman tests were applied. RESULTS: We obtained a prognostic model for assessing the grade III and IV glioma cell malignancy based on expression of marker genes MDM2, MELK, SOX2, CDK4, DR5 and OCT4. Predictive accuracy was 83% (Akaike information criterion -55.125).