title: Intervention in growth factor activated signaling pathways by renally targeted kinase inhibitors.
abstract: Cell-specific targeting to renal tubular cells is an interesting approach to enhance the accumulation of drugs in the kidney. Low molecular weight proteins are rapidly filtered and extensively accumulate in proximal tubular cells. We therefore have used lysozyme (LZM, 14 kDa) as a tubular cell-specific carrier for the delivery of kinase inhibitors. Two different kinase inhibitors (LY364947 and erlotinib, directed to either the TGF-beta receptor kinase or the EGF receptor) were individually conjugated to LZM via a novel platinum-based linker (Universal Linkage System; ULS). The cellular handling and pharmacological efficacy of the conjugates were evaluated in cultured proximal tubular cells (HK-2 cells). Both conjugates were efficiently internalized via endocytosis. TGF-beta or EGF activated HK-2 cells showed a strong activation of the studied kinases and the conjugates inhibited these events, as was demonstrated by Western blotting of phosphorylated downstream mediators and quantitative gene expression analysis. In conclusion, we have developed tubular cell-specific kinase inhibitor-LZM conjugates via a novel linker strategy, which both showed to be effective in vitro. Future in vivo studies should show their potential for the treatment of renal diseases.
authors.affiliation: Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, The Netherlands.
authors.forename: Marjan M
authors.initials: MM
authors.lastname: Fretz
authors.forename: M E Emmy M
authors.initials: ME
authors.lastname: Dolman
authors.forename: Marie
authors.initials: M
authors.lastname: Lacombe
authors.forename: Jai
authors.initials: J
authors.lastname: Prakash
authors.forename: Tri Q
authors.initials: TQ
authors.lastname: Nguyen
authors.forename: Roel
authors.initials: R
authors.lastname: Goldschmeding
authors.forename: Janos
authors.initials: J
authors.lastname: Pato
authors.forename: Gert
authors.initials: G
authors.lastname: Storm
authors.forename: Wim E
authors.initials: WE
authors.lastname: Hennink
authors.forename: Robbert J
authors.initials: RJ
authors.lastname: Kok
mesh_terms: D002478:Cells, Cultured; D002626:Chemistry, Pharmaceutical; D004337:Drug Carriers; D004705:Endocytosis; D004815:Epidermal Growth Factor / Q000378:metabolism; D066246:ErbB Receptors / Q000037:antagonists & inhibitors / Q000378:metabolism; D000069347:Erlotinib Hydrochloride; D005355:Fibrosis; D005786:Gene Expression Regulation / Q000187:drug effects; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000378:metabolism*; D007687:Kidney Tubules, Proximal / Q000187:drug effects* / Q000201:enzymology; D007700:Kinetics; D009113:Muramidase / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation; D047428:Protein Kinase Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D011720:Pyrazoles / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D011758:Pyrroles / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D011799:Quinazolines / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D018125:Receptors, Transforming Growth Factor beta / Q000037:antagonists & inhibitors / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D016212:Transforming Growth Factor beta / Q000378:metabolism; D011804:Quinolines
chemical_list: D004337:Drug Carriers; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D000069347:Erlotinib Hydrochloride; D036341:Intercellular Signaling Peptides and Proteins; D009113:Muramidase; D047428:Protein Kinase Inhibitors; D011720:Pyrazoles; D011758:Pyrroles; D011799:Quinazolines; D018125:Receptors, Transforming Growth Factor beta; D016212:Transforming Growth Factor beta; C506615:HTS 466284; D011804:Quinolines; C512478:EGFR protein, human