p53-MDM2/MDMX interaction inhibitors represent the prospective agents for targeted anticancer therapy in tumors expressing wild-type p53 protein. Imidazoline-based MDM2-targeted inhibitors of such ...type, nutlins, contain halogen-substituted phenyl rings, which dramatically decrease the solubility of compounds in water. The addition of suitable hydrophilic substituents in benzene rings and to imidazoline nitrogen can improve the compound’s water solubility. In this study, we have synthesized novel hydrophilic cis-2,4,5-tris(alkoxyphenyl)imidazolines and studied the influence of N-sulfonyl substituent on protein-protein interaction compared to unsubstituted alkoxy-compounds. The biological activity of the obtained compounds was studied using Western blot analysis on A549, RKO and SH-SY5Y cancer cell lines. It was found that the derivatives are able to inhibit MDM2/MDMX-p53 interaction, promote p53 stabilization and induce p21 expression in the concentrations from 500 nM.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
As an important regulator of apoptosis, Mcl-1 protein, a member of the Bcl-2 family, represents an attractive target for cancer treatment. The recent development of novel small molecule compounds has ...allowed Mcl-1-inhibitory therapy to proceed to clinical trials in cancer treatment. However, the possible adverse effects of either direct inhibition of Mcl-1 or upregulation of Mcl-1S, proapoptotic isoform resulting from alternative splicing of Mcl-1, remain unclear. Here, we investigated changes in Mcl-1S levels during cell cycle and the cell cycle-related functions of Mcl-1 isoforms to address the above-mentioned concerns. It was shown that an anti-mitotic agent monastrol caused accumulation of Mcl-1S mRNA, although without increasing the protein level. In contrast, both mRNA and protein levels of Mcl-1S accrued during the premitotic stages of the normal cell cycle progression. Importantly, Mcl-1S was observed in the nuclear compartment and an overexpression of Mcl-1S, as well as knockdown of Mcl-1, accelerated the progression of cells into mitosis and resulted in DNA damage accumulation. Surprisingly, a small molecule inhibitor of Mcl-1, BH3-mimetic S63845, did not affect the cell cycle progression or the amount of DNA damage. In general, upregulated Mcl-1S protein or genetically inhibited Mcl-1L were associated with the cell cycle perturbations and DNA damage accumulation in normal and cancer cells. At the same time, BH3-mimetic to Mcl-1 did not affect the cell cycle progression, suggesting that direct inhibition of Mcl-1 is devoid of cell-cycle related undesired effects.
Silicon nanoparticles (SiNP) are currently of great interest, especially in biomedicine, because of their unique physicochemical properties combined with biodegradability. SiNPs can be obtained in ...various ways and can have either a non-porous solid (sol-) or porous (por-) structure. In this work, we carry out detailed optical monitoring of sol- and por-SiNP biodegradation using Raman and photoluminescence (PL) micro-spectroscopy. SiNPs were obtained by ultrasound grinding of sol- or por-silicon nanowires, created by silver-assisted chemical etching of crystalline Si with different doping levels. In this case, sol-SiNPs consist of nanocrystals 30 nm in size, while por-SiNPs consist of small 3 nm nanocrystals and 16 nm pores. Both SiNPs show low in vitro cytotoxicity towards MCF-7 and HEK293T cells up to 800 μg/mL. The appearance of the F-band (blue–yellow) PL, as well as a decrease in the intensity of the Raman signal, indicate the gradual dissolution of the sol-SiNPs during 20 days of incubation. At the same time, the rapid dissolution of por-SiNP within 24 h is identified by the quenching of their S-band (red) PL and the disappearance of the Raman signal. The obtained results are important for development of intelligent biodegradable drug delivery systems based on SiNPs.
Coherent anti-Stokes Raman scattering (CARS), a nonlinear optical method for rapid visualization of biological objects, represents a progressive tool in biology and medicine to explore cells and ...tissue structures in living systems and biopsies. In this study, we report efficient nonresonant CARS imaging of silicon nanoparticles (SiNPs) in human cells as a proof of concept. As both bulk and porous silicon exhibit a high third-order nonlinear susceptibility, χ
, which is responsible for the CARS intensity, it is possible to visualize the SiNPs without specific labels. Porous and solid SiNPs were obtained from layers of porous and nonporous silicon nanowires and mesoporous silicon. Electron microscopy and Raman spectroscopy showed that porous SiNPs consisted of ∼3 nm silicon nanocrystals (nc-Si) and pores, whereas solid nanoparticles comprised ∼30 nm nc-Si. All types of SiNPs were nontoxic at concentrations up to 500 μg/mL after 24 h of incubation with cells. We demonstrated that although nc-Si possesses a distinguished narrow Raman band of about 520 cm
, it is possible to detect a high CARS signal from SiNPs in the epi-direction even in a nonresonant regime. 3D CARS images showed that all types of studied SiNPs were visualized as bright spots inside the cytoplasm of cells after 3-6 h of incubation because of the contrast provided by the high third-order nonlinear susceptibility of SiNPs, which is 1 × 10
to 1 × 10
times higher than that of water and typical biological media. Overall, CARS microscopy can provide localization of SiNPs within biological structures at the cellular level and can be a powerful tool for in vitro monitoring of silicon-based drug delivery systems or use SiNPs as labels to monitor various bioprocesses inside living cells.
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IJS, KILJ, NUK, PNG, UL, UM
The use of p53-MDM2/X inhibitors is a prospective strategy in anti-cancer therapy for tumors with wild type p53 protein. In our study, new low-molecular-weight inhibitors of the p53-mdm2 interaction ...have been proposed. The two-step synthesis of the imidazoline core with subsequent modifications for the nitrogen atom was carried out. New molecules caused the accumulation of p53 protein levels more than seven times than in comparison with the control. The accumulation of proapoptotic proteins such as p21 and PUMA has also been investigated, and the mechanism of cell death has been shown.
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