Vol 51, No 3 (2025)

This review article deals with physical methods for investigating the structural characteristics of inclusion complexes of supramers of phospholipid derivatives of cyclodextrins. Phospholipid derivatives of cyclodextrins are formed by attaching a phospholipid moiety to the cyclodextrin molecule. This modification imparts additional structural features to the cyclodextrin, increasing its solubility and stability in aqueous media. These new compounds can self-assemble in aqueous media into different types of supramolecular nanocomplexes. Biomedical applications are envisaged for nanoencapsulation of drug molecules in hydrophobic interchain volumes and nanocavities of amphiphilic cyclodextrins (serving as drug carriers or pharmaceutical excipients), antitumour phototherapy, gene delivery, and protection of unstable active ingredients by complexation of inclusions in nanostructured media. The focus is on the study of nanoparticle morphology, as efficient delivery systems must fulfil certain requirements. Classical physical methods cannot provide detailed information on the properties of potential structures for biomedical applications. For this purpose, the search for new non-invasive approaches is necessary.

Tumor cell death induction via activation of TRAIL (tumor necrosis factor-related apoptosis inducing ligand) cytokine signaling pathway is a promising strategy for anticancer therapy. Previously, we developed a fusion protein SRH-DR5-B-iRGD based on the DR5 (death receptor 5)-specific cytokine TRAIL variant DR5-B with antiangiogenic peptides. The SRH peptide specifically binds to the VEGFR2 (vascular endothelial growth factor receptor 2) receptor and blocks its VEGF-mediated activation; the iRGD peptide binds to integrin αvβ3 and the NRP-1 (neuropilin-1) receptor. All of these targets are known to be overexpressed on the surface of tumor cells. In the current study, we investigated the cytotoxic activity of the SRH-DR5-B-iRGD fusion protein in comparison with DR5-B in vitro in ovarian and breast adenocarcinoma cell lines with different BRCA mutation status in combination with a targeted poly(ADP-ribose) polymerase (PARP) inhibitor olaparib. Olaparib synergistically enhanced the cytotoxicity of TRAIL-based proteins regardless of the presence of BRCA mutations in the cells, and this effect was more pronounced for SRH-DR5-B-iRGD. Thus, the combination of SRH-DR5-B-iRGD with olaparib can be considered as a new approach to treatment of ovarian and breast adenocarcinomas regardless of the presence of BRCA mutations.

The interaction of 3β-acetoxyurs-12-en-28-oyl chloride with potassium rhodanide afforded 3β-acetoxyurs-12-en-28-oyl isothiocyanate. A series of substituted 3β-acetoxy-urs-12-en-28-oyl-thioureas was synthesised in yields of 69–88% by condensation of triterpene acyl isothiocyanate with a series of amino derivatives. The CuAAC cycloaddition reaction of N-(2-azidoethylcarbamothioyl)-3-acetoxyurs-12-en-28-oyl-amide with propargyl alcohol and 3-(prop-2-inyloxy)-4,5-((R,S)-methoxymethylenedioxy)-benzoate led to the formation of hybrid acylthioureas containing a 1,2,3-triazole linker in 72 and 75% yields. In CuAAC reactions of N-(prop-2-ynylcarbamothioyl)-3β-acetoxyurs-12-en-28-oylamide with substituted acylthiourea azides containing 1,2,3-triazole were isolated in moderate yields of 48–62%. The use of one-pot-reactor version of the synthesis with the preparation of substituted (1H-1,2,3-triazol-4-yl)methanamines in the reaction of propargylamine with substituted azides followed by condensation with 3β-acetoxyurs-12-en-28-oyl isothiocyanate increased the yield of 1,2,3-triazole-containing acylthioureas to 65–85%. Polar triterpene acylthioureas containing carboxyl or alcohol groups exhibited high inhibitory activity against HepG2 cells, significantly superior to the parent compound ursolic acid, and were also more selective than the drug doxorubicin. Among the acylthioureas, products of CuAAC cycloaddition, the most active was the polar derivative with (1H-1,2,3-triazol-4-yl)methanol substituent, which was cytotoxic to all cells tested, including the non-tumour control, but superior in selectivity to doxorubicin. Ursane hybrids with acylthiourea derivatives are of interest for further investigation as promising antitumour agents.

The regulation of substrate surface properties in biochip technology opens the possibility of optimizing platforms for efficient biomolecule recognition. The research is aimed at exploring the use of brush polymers to improve the sensitivity and speed of DNA analysis on biochips. Brush polymer cells for biochips were prepared by UV-initiated polymerization of monomers from the surface on polyethylene terephthalate substrates. Cross-linked hydrogel polymer cells for biochips were prepared on polybutylene terephthalate substrates by copolymerization of gel components with DNA probes. The probes in brush polymer cells were immobilized through activated carboxyl groups. A single-stranded DNA target with a length of 124 nucleotides corresponding to the 7th exon of the human ABO gene was used for hybridization analysis. Hybridization of the DNA target was studied on biochips with cells made of brush polymers and cross-linked polyacrylamide hydrogels. The results of hybridization analysis on biochips were evaluated by digital fluorescence microscopy. Higher intensity of fluorescence signals and higher ratio of signals of cells with perfect duplexes to those of cells with imperfect duplexes were observed in cells from brush polymers compared to cells from 3D cross-linked polymers. Achievement of hybridization signal up to 90% of saturation occurred in the same time in both cell types. The relevance of this work stems from the need for highly accurate and efficient diagnostic methods to analyze biomolecules with minimal time and reagent consumption. The development of biochips based on brush polymers will increase the accuracy and sensitivity of molecular studies, which is especially important for early diagnosis of diseases.

Neurogenic tumors such as neuroblastoma and glioblastoma are highly heterogeneous and particularly aggressive: they are characterized by rapid growth, metastasis and resistance to treatment. Both tumors exhibit MYCN oncogene copy-number disruption, impaired gene transcription, and overall high transcriptional deregulation. In this study, we evaluated the survival of glioblastoma and neuroblastoma cells and performed real-time PCR analysis to assess the change in expression of MYCN, HAND2, PHOX2A, and PHOX2B oncogenes after exposure to senecin B in combination with temozolomide and the potential therapeutic agent 10058-F4. As a result, a trend of increased PHOX2B gene expression and decreased PHOX2A gene expression after drug exposure was observed in one of the neuroblastoma lines and both glioblastoma lines, an increase in MYCN and HAND2 gene expression was also observed. Viability tests showed that substance 10058-F4 was effective against neuroblastoma line but not glioblastoma lines. However, senexin B enhanced the inhibitory effect of 10058-F4 on glioblastoma cell lines and also enhanced the effect of temozolomide on the T98G cell line.

Here, we studied the regulation of pou5f3 family transcripts stability by association with Ybx1, a protein of ribonucleoprotein complexes. It is known that the clawed frog Xenopus laevis has three genes belonging to the POU5 family: pou5f3.1/oct91, pou5f3.2/oct25, and pou5f3.3/oct60. The Pou5f3 family factors are orthologues of the mammalian embryonic stem cell OCT4 pluripotency factor. However, the expression patterns of these genes differ over time. Pou5f3.3/oct60 transcripts are stored in oocytes, are present in large quantities in fertilized eggs, and then degrade only after fertilization. Pou5f3.2/oct25 transcripts are also present in the zygote, but their numbers increase even more during the development process. Finally, pou5f3.1/oct91 transcription begins only after the activation of the embryo genome at the middle blastula stage. In the present work, we revealed a much higher specificity of the Ybx1 factor to form a complex with the maternal mRNA of the pou5f3.3/oct60 gene compared to zygotic mRNAs of the pou5f3.1/oct91 and pou5f3.2/oct25 genes. Since Ybx1 is a protein that, on the one hand, is involved in interaction with cytoskeletal proteins, and, on the other hand, binds and stabilizes pluripotency genes mRNA, it can play a linking role in between the degradation of these maternal transcripts and cytoskeletal rearrangements during the onset of morphogenetic cell movements in the process of formation of germ layers.

Condensation of 1-(4-alkoxyphenyl)ethanones with aromatic aldehydes in the presence of sodium hydroxide in an aqueous-ethanol solution yielded (2E)-3-aryl-1-(4-alkoxyphenyl)prop-2-en-1-ones. Subsequent oxidation of the latter with hydrogen peroxide in a water-ethanol system in a basic medium at room temperature yielded the corresponding epoxy derivatives. The effect of the synthesized compounds on tumor DNA methylation processes in vitro and the antitumor activity of [4-(pentyloxy)phenyl)](3-phenyloxiran-2-yl)methanone in vivo were assessed.

Here we investigate the effect of the C-terminal region on the solubility of TLR4 and TLR10 TIR domains upon the heterologous expression in Escherichia coli. We demonstrated that the absence of this region significantly enhances the yields of globular domains in a soluble form. These findings complement the protocols, previously established to synthesize the TLR TIR domains for the structural studies by various techniques, including by NMR spectroscopy.

We investigated the efficiency of labeling the GC-rich promoter region of the TERT gene in the human genome with derivatives of 5′-triphosphates of 2′-deoxyuridine (dU) and 2'-deoxycytidine (dC) containing cyanine dyes Cy5 and Cy7 as a fluorescent label. The effect of modified nucleotides on the efficiency of the polymerase chain reaction was evaluated by real-time PCR, and the extent of nucleotide incorporation into the PCR product was also determined. The efficiency of DNA matrix labeling was determined by the intensity of fluorescent signal during allele-specific hybridization on a biological microarray. The highest level of biochip cell fluorescence was observed for dU-Cy7 derivatives compared to dU- and dC-Cy5 derivatives. At the same time, in the case of GC-rich DNA matrix, the use of dC-Cy5 derivatives gave a fundamentally better result compared to dU-Cy5 derivative. Thus, modified Cy7 analogs capable of incorporation into DNA during PCR are less dependent on the GC composition of the DNA matrix and are more universal fluorescent labels for diagnostic purposes. Further application of modified Cy7 analogs in the development of laboratory-on-a-chip test systems seems to be the most promising.