Molecular Mechanisms of Anticancer Activity of N-Glycosides of Indolocarbazoles LCS-1208 and LCS-1269

Abstract

Novel indolocarbazole derivatives named LCS were synthesized by our research group. Two of them were selected as the most active anticancer agents in vivo. We studied the mechanisms of anticancer activity in accordance with the previously described effects of indolocarbazoles. Cytotoxicity was estimated by MTT assay. We analyzed LCS-DNA interactions by circular dichroism in cholesteric liquid crystals and fluorescent indicator displacement assay. The effect on the activity of topoisomerases I and II was studied by DNA relaxation assay. Expression of interferon signaling target genes was estimated by RT-PCR. Chromatin remodeling was analyzed–the effect on histone H1 localization and reactivation of epigenetically silenced genes. LCS-induced change in the expression of a wide gene set was counted by means of PCR array. Our study revealed the cytotoxic activity of the compounds against 11 cancer cell lines and it was higher than in immortalized cells. Both compounds bind DNA; binding constants were estimated—LCS-1208 demonstrated higher affinity than LCS-1269; it was shown that LCS-1208 intercalates into DNA that is typical for rebeccamycin derivatives. LCS-1208 also inhibits topoisomerases I and IIα. Being a strong intercalator and topoisomerase inhibitor, LCS-1208 upregulates the expression of interferon-induced genes. In view of LCSs binding to DNA we analyzed their influence on chromatin stability and revealed that LCS-1269 displaces histone H1. Our analysis of chromatin remodeling also included a wide set of epigenetic experiments in which LCS-1269 demonstrated complex epigenetic activity. Finally, we revealed that the antitumor effect of the compounds is based not only on binding to DNA and chromatin remodeling but also on alternative mechanisms. Both compounds induce expression changes in genes involved in neoplastic transformation and target genes of the signaling pathways in cancer cells. Despite of being structurally similar, each compound has unique biological activities. The effects of LCS-1208 are associated with intercalation. The mechanisms of LCS-1269 include influence on higher levels such as chromatin remodeling and epigenetic effects.

Effects of G-Quadruplex-Binding Plant Secondary Metabolites on c-MYC Expression

“…Based on these curves, we estimated DC 50 values for all PSM ligands and G4s used, as described by Monchaud et al [ 35 , 36 ] ( Table 2 ). Binding constants characterizing the affinity of PSMs were calculated using the values of PSM DC 50 and the binding constant of TO [ 20 , 37 , 38 ].…”

“…The binding constants ( K b ) were calculated using the following equation: where K b and K f are the PSM- and TO-binding constants, respectively; L and F are the concentrations of PSM (ligand) and TO (fluorophore), respectively; I (0) and I ( L ) are TO fluorescence without a PSM ligand and in the presence of a ligand with a concentration of L [ 37 , 38 ]. L required to reduce TO fluorescence by 50% (DC 50 ) was detected from the plots and used to simplify the equation: …”

Relevant Advances in the Synthesis and Applications of N‐Glycopyranosides

“…[83][84][85][86][87][88][89][90] The synthesis of glycosides continues to be a challenge, especially of N-glycosides, since the available methodologies have some type of limitation, namely, they involve high-cost reagents and catalysts; yields are generally moderate; moderate stereoselectivity, which makes purification difficult; use of high temperatures; and synthetic routes with multiple reaction steps. [92,93] Molecule Żurawska et al [83] 2 Molecular Mechanisms of Anticancer Activity of N-Glycosides of Indolocarbazoles LCS-1208 and LCS-1269 Molecule Zenkov et al [84] 3 Self-Promoted Glycosylation for the Synthesis of β-N-Glycosyl Sulfonyl Amides European Journal of Organic. Chemistry Mala and Perdesen [85] 4 Synthesis of N-Glycosides by Silver-Assisted Gold Catalysis.…”

Antiproliferative activity of a new derivative from the class of N-glycoside of indolo[2,3-a]pyrrolo[3,4-c]carbazoles

“…So far, an extensive database on the antiproliferative activity of indolocarbazoles with various chemical structures has been compiled, which makes it possible to consider such substances as promising for carrying out further study (Caruso et al 2019;Zenkov et al 2021). Indolocarbazole derivatives containing glycoside substituents attached to the pharmacophore via nitrogen atoms are of special interest (Sánchez et al 2006;Wada et al 2007;Kiseleva et al 2019).…”