Theoretical Assessment of the Ligand/Metal/Quadruplex Recognition in the Non-Canonical Nucleic Acids Structures.

Quadruplexes (GQs), peculiar DNA/RNA motifs concentrated in specific genomic regions, play a vital role in biological processes including telomere stability and, hence, represent promising targets for anticancer therapy. GQs are formed by folding guanine-rich sequences into square planar G-tetrads which stack onto one another. Metal cations, most often potassium, further stabilize the architecture by coordinating the lone electron pairs of the O atoms.

Small Heterocyclic Ligands as Anticancer Agents: QSAR with a Model G-Quadruplex.

G-quadruplexes (GQs) have become valid targets for anticancer studies in recent decades due to their multifaceted biological function. Herewith, we aim to quantify interactions of potential heterocyclic ligands (Ls) with model GQs. For seven 4-aminoquinazolines and three 2-heteroaryl perimidines, seven of this ten-membered group so far unknown, we use routine quantum chemical modeling.

Biological activity of quinazoline analogues and molecular modeling of their interactions with G-quadruplexes.

Background: Quinazolines 1 to 6, with an aromatic or aryl-vinyl substituent in position 2 are selected with the aim to compare their structures and biological activity. The selection includes a natural alkaloid, schizocommunin, and the synthetic 2-(2'-quinolyl)-3H-quinazolin-4-one, known to interact with guanine-quadruplex dependent enzymes, respectively telomerase and topoisomerase.

Methods: Breast cancer cells of the MDA cell line have been used to study the bioactivity of the tested compounds by the method of Comet Assay and FACS analyses.

Ureterolysis with ureterotomy and omental sleeve wrap in patients with radiation induced pelvic retroperitoneal fibrosis.

Introduction: Secondary retroperitoneal fibrosis (RPF) due to pelvic radiation alone or together with pelvic surgery is one of the causes of obstructive renal failure. Ureteral obstruction is caused by ischemic stricture and encasement by fibrotic tissue. Endo-ureterotomy alone, without vascular supply, is not successful in these cases.