title: Design, synthesis and characterization of peptidomimetic conjugate of BODIPY targeting HER2 protein extracellular domain.
abstract: Among the EGFRs, HER2 is a major heterodimer partner and also has important implications in the formation of particular tumors. Interaction of HER2 protein with other EGFR proteins can be modulated by small molecule ligands and, hence, these protein-protein interactions play a key role in biochemical reactions related to control of cell growth. A peptidomimetic (compound 5-1) that binds to HER2 protein extracellular domain and inhibits protein-protein interactions of EGFRs was conjugated with BODIPY (4,4-difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-s-indacene). Conjugation of BODIPY to the peptidomimetic was investigated by different approaches. The conjugate was characterized for its ability to bind to HER2 overexpressing SKBR-3 and BT-474 cells. Furthermore, cellular uptake of conjugate of BODIPY was studied in the presence of membrane tracker and Lyso tracker using confocal microscopy. Our results suggested that fluorescently labeled compound 5-7 binds to the extracellular domain and stays in the membrane for nearly 24 h. After 24 h there is an indication of internalization of the conjugate. Inhibition of protein-protein interaction and downstream signaling effect of compound 5-1 was also studied by proximity ligation assay and Western blot analysis. Results suggested that compound 5-1 inhibit protein-protein interactions of HER2-HER3 and phosphorylation of HER2 in a time-dependent manner.
authors.affiliation: Basic Pharmaceutical Sciences, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71201, USA.
authors.forename: Sashikanth
authors.initials: S
authors.lastname: Banappagari
authors.forename: Alecia
authors.initials: A
authors.lastname: McCall
authors.forename: Krystal
authors.initials: K
authors.lastname: Fontenot
authors.forename: M Graca H
authors.initials: MG
authors.lastname: Vicente
authors.forename: Amit
authors.initials: A
authors.lastname: Gujar
authors.forename: Seetharama
authors.initials: S
authors.lastname: Satyanarayanajois
mesh_terms: D001896:Boron Compounds / Q000737:chemistry*; D045744:Cell Line, Tumor; D004305:Dose-Response Relationship, Drug; D015195:Drug Design; D066246:ErbB Receptors / Q000037:antagonists & inhibitors; D006801:Humans; D015394:Molecular Structure; D057786:Peptidomimetics / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding / Q000187:drug effects; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000096:biosynthesis / Q000378:metabolism; D020893:Receptor, ErbB-3 / Q000037:antagonists & inhibitors / Q000378:metabolism; D013329:Structure-Activity Relationship; D013997:Time Factors
chemical_list: D001896:Boron Compounds; D066246:ErbB Receptors; D057786:Peptidomimetics; D018719:Erb-b2 Receptor Tyrosine Kinases; D020893:Receptor, ErbB-3; C095489:4,4-difluoro-4-bora-3a,4a-diaza-s-indacene; C508053:ERBB2 protein, human; C581292:ERBB3 protein, human
keywords: BODIPY; Breast cancer; EGFR; HER2; Peptidomimetic; Phosphorylation; Protein–protein interactions