Investigating the antiproliferative activity of high affinity DNA aptamer on cancer cells.
Vascular endothelial growth factor (VEGF) is an angiogenic mitogen involved in promoting tumor angiogenesis inside the body. VEGF is a key protein required for progression of tumor from benign to malignant phenotype. In this study, we investigated the binding affinity of a previously selected 26-mer DNA aptamer sequence (SL(2)-B) against heparin binding domain (HBD) of VEGF(165) protein. The SL(2)-B was first chemically modified by introduction of phosphorothioate linkages (PS-linkages). Subsequently, surface plasmon resonance (SPR) spectroscopy and circular dichroism (CD) were used to determine the binding affinity, specificity and to deduce the conformation of PS-modified SL(2)-B sequence. Finally, antiproliferative activity of the modified SL(2)-B sequence on Hep G2 cancer cells was investigated. Our results demonstrate a marked enhancement in the biostability of the SL(2)-B sequence after PS modification. The modified SL(2)-B sequence also exhibits enhanced antiproliferative activity against Hep G2 cancer cells in hypoxia conditions. In addition, modified SL(2)-B sequence inhibits the expression of Jagged-1 protein, which is one of the ligands to VEGF linked delta/jagged-notch signaling pathway.
Department of Chemical and Biomolecular Engineering, Faculty of Engineering, National University of Singapore, Singapore, Singapore.
Harleen
H
Kaur
Jasmine J
JJ
Li
Boon-Huat
BH
Bay
Lin-Yue Lanry
LY
Yung
D017304:Annexin A5 / Q000378:metabolism; D052157:Aptamers, Nucleotide / Q000378:metabolism / Q000494:pharmacology* / Q000627:therapeutic use*; D001483:Base Sequence; D015153:Blotting, Western; D002135:Calcium-Binding Proteins / Q000378:metabolism; D002457:Cell Extracts; D049109:Cell Proliferation / Q000187:drug effects; D002942:Circular Dichroism; D003851:Deoxyribonucleases / Q000378:metabolism; D004354:Drug Screening Assays, Antitumor; D005434:Flow Cytometry; D056945:Hep G2 Cells; D006801:Humans; D055767:Immobilized Proteins / Q000378:metabolism; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism; D000072100:Jagged-1 Protein; D007700:Kinetics; D008565:Membrane Proteins / Q000378:metabolism; D009369:Neoplasms / Q000188:drug therapy* / Q000473:pathology; D009946:Organothiophosphorus Compounds / Q000378:metabolism; D011485:Protein Binding / Q000187:drug effects; D000072099:Serrate-Jagged Proteins; D044967:Serum; D020349:Surface Plasmon Resonance; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
D017304:Annexin A5; D052157:Aptamers, Nucleotide; D002135:Calcium-Binding Proteins; D002457:Cell Extracts; D055767:Immobilized Proteins; D036341:Intercellular Signaling Peptides and Proteins; C000606273:JAG1 protein, human; D000072100:Jagged-1 Protein; D008565:Membrane Proteins; D009946:Organothiophosphorus Compounds; D000072099:Serrate-Jagged Proteins; D042461:Vascular Endothelial Growth Factor A; D003851:Deoxyribonucleases