title: Long-lasting inhibition of EGFR autophosphorylation in A549 tumor cells by intracellular accumulation of non-covalent inhibitors.
abstract: In the present study, a small set of reversible or irreversible 4-anilinoquinazoline EGFR inhibitors was tested in A549 cells at early (1h) and late (8h) time points after inhibitor removal from culture medium. A combination of assays was employed to explain the observed long-lasting inhibition of EGFR autophosphorylation. We found that EGFR inhibition at 8h can be due, besides to the covalent interaction of the inhibitor with Cys797, as for PD168393 (2) and its prodrug 4, to the intracellular accumulation of non-covalent inhibitors by means of an active cell uptake, as for 5 and 6. Compounds 5-6 showed similar potency and duration of inhibition of EGFR autophosphorylation as the covalent inhibitor 2, while being devoid of reactive groups forming covalent bonds with protein thiols.
authors.affiliation: Dipartimento di Farmacia, Università degli Studi di Parma, Parma, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Vacondio
authors.forename: Caterina
authors.initials: C
authors.lastname: Carmi
authors.forename: Elena
authors.initials: E
authors.lastname: Galvani
authors.forename: Michele
authors.initials: M
authors.lastname: Bassi
authors.forename: Claudia
authors.initials: C
authors.lastname: Silva
authors.forename: Alessio
authors.initials: A
authors.lastname: Lodola
authors.forename: Silvia
authors.initials: S
authors.lastname: Rivara
authors.forename: Andrea
authors.initials: A
authors.lastname: Cavazzoni
authors.forename: Roberta R
authors.initials: RR
authors.lastname: Alfieri
authors.forename: Pier Giorgio
authors.initials: PG
authors.lastname: Petronini
authors.forename: Marco
authors.initials: M
authors.lastname: Mor
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D045744:Cell Line, Tumor; D002626:Chemistry, Pharmaceutical; D066246:ErbB Receptors / Q000037:antagonists & inhibitors*; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D010766:Phosphorylation / Q000187:drug effects; D011799:Quinazolines / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D013997:Time Factors
chemical_list: C527769:6-hydroxypropynyl-4-anilinoquinazoline; D000814:Aniline Compounds; C509204:PD168393; D011799:Quinazolines; D066246:ErbB Receptors
keywords: A549 cell line; Active transport; EGFR; HPLC–MS/MS; Irreversible inhibitors