Interaction of Camptothecin Anticancer Drugs with Ribosomal Proteins L15 and L11: A Molecular Docking Study

Abstract

The antitumor drug topotecan (TPT) is a potent inhibitor of topoisomerase I, triggering DNA breaks lethal for proliferating cancer cells. The mechanism is common to camptothecins SN38 (the active metabolite of irinotecan) and belotecan (BLT). Recently, TPT was shown to bind the ribosomal protein L15, inducing an antitumor immune activation independent of topoisomerase I. We have modeled the interaction of four camptothecins with RPL15 derived from the 80S human ribosome. Two potential drug-binding sites were identified at Ile135 and Phe129. SN38 can form robust RPL15 complexes at both sites, whereas BLT essentially gave stable complexes with site Ile135. The empirical energy of interaction (ΔE) for SN38 binding to RPL15 is similar to that determined for TPT binding to the topoisomerase I-DNA complex. Molecular models with the ribosomal protein L11 sensitive to topoisomerase inhibitors show that SN38 can form a robust complex at a single site (Cys25), much more stable than those with TPT and BLT. The main camptothecin structural elements implicated in the ribosomal protein interaction are the lactone moiety, the aromatic system and the 10-hydroxyl group. The study provides guidance to the design of modulators of ribosomal proteins L11 and L15, both considered anticancer targets.

Synthesis, Molecular Electron Density Theory Study, Molecular Docking, and Pharmacological Evaluation of New Coumarin–Sulfonamide–Nitroindazolyl–Triazole Hybrids as Monoamine Oxidase Inhibitors

“…The same procedure was used to establish molecular models for all compounds. The procedure has been previously described with other protein–ligand complexes [ 81 , 82 ].…”

Insights into the Mechanism of Action of the Degraded Limonoid Prieurianin

“…Same models in panels (d-f) for compound (5). The modeling analysis was performed as previously described in [109,110]. The docking process has been described previously [109,110].…”

“…The modeling analysis was performed as previously described in [109,110]. The docking process has been described previously [109,110]. The docking analysis was performed with Hsp47 (PDB code 3ZHA [111]), keeping the following amino acids totally flexible: Arg222, Tyr245, Asp247, Met271, His273, Leu381, Tyr383, Asp385, His386 and Arg11 (E collagen unit).…”

“…Same models in panels (d-f) for compound(5). The modeling analysis was performed as previously described in[109,110].…”