Novel Dihydropyrimidinone-Derived Selenoesters as Potential Cytotoxic Agents to Human Hepatocellular Carcinoma: Molecular Docking and DNA Fragmentation

Author(s):

Jean C. Benassi, Flavio A.R. Barbosa, Valdelúcia M.A.S. Grinevicius, Fabiana Ourique, Daniela Coelho, Karina B. Felipe, Antônio L. Braga, Danilo W. Filho and Rozangela C. Pedrosa*   Pages 703 - 715 ( 13 )

Abstract:

<P>Background and Objective: Evidence point out promising anticancer activities of Dihydropyrimidinones (DHPM) and organoselenium compounds. This study aimed to evaluate the cytotoxic and antiproliferative potential of DHPM-derived selenoesters (Se-DHPM), as well as their molecular mechanisms of action. </P><P> Methods: Se-DHPM cytotoxicity was evaluated against cancer lines (HeLa, HepG2, and MCF-7) and normal cells (McCoy). HepG2 clonogenic assay allowed verifying antiproliferative effects. The propidium iodide/ orange acridine fluorescence readings showed the type of cell death induced after treatments (72h). Molecular simulations with B-DNA and 49H showed docked positions (AutoDock Vina) and trajectories/energies (GROMACS). In vitro molecular interactions used CT-DNA and 49H applying UV-Vis absorbance and fluorescence. Comet assay evaluated DNA fragmentation of HepG2 cells. Flow cytometry analysis verified HepG2 cell cycle effects. Levels of proteins (&#946;-actin, p53, BAX, HIF-1&#945;, &#947;H2AX, PARP-1, cyclin A, CDK-2, and pRB) were quantified by immunoblotting. </P><P> Results: Among Se-DHPM, 49H was selectively cytotoxic to HepG2 cells, reduced cell proliferation, and increased BAX (80%), and p53 (66%) causing apoptosis. Molecular assays revealed 49H inserted in the CT-DNA molecule causing the hypochromic effect. Docking simulations showed H-bonds and hydrophobic interactions, which kept the ligand partially inserted into the DNA minor groove. 49H increased the DNA damage (1.5 fold) and &#947;H2AX level (153%). Besides, treatments reduced PARP-1 (60%) and reduced pRB phosphorylation (21%) as well as decreased cyclin A (46%) arresting cell cycle at the G1 phase. </P><P> Conclusion: Together all data obtained confirmed the hypothesis of disruptive interactions between Se-DHPM and DNA, thereby highlighting its potential as a new anticancer drug.</P>

Keywords:

HepG2, dihydropyrimidinones, organoselenium, molecular docking, DNA damage, cell, apoptosis.

Affiliation:

Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, Department of Chemistry, Federal University of Santa Catarina, Florianópolis, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis, Departament of Clinical Analysis, Federal University of Parana, Curitiba, Department of Chemistry, Federal University of Santa Catarina, Florianópolis, Departament of Ecology and Zoology, Federal University of Santa Catarina, Florianópolis, Department of Biochemistry, Federal University of Santa Catarina, Florianópolis

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