title: N-Acetylgalactosamine-Targeted Delivery of Dendrimer-Doxorubicin Conjugates Influences Doxorubicin Cytotoxicity and Metabolic Profile in Hepatic Cancer Cells.
abstract: This study describes the development of targeted, doxorubicin (DOX)-loaded generation 5 (G5) polyamidoamine dendrimers able to achieve cell-specific DOX delivery and release into the cytoplasm of hepatic cancer cells. G5 is functionalized with poly(ethylene glycol) (PEG) brushes displaying N-acetylgalactosamine (NAcGal) ligands to target hepatic cancer cells. DOX is attached to G5 through one of two aromatic azo-linkages, L3 or L4, achieving either P1 ((NAcGalβ-PEGc)16.6-G5-(L3-DOX)11.6) or P2 ((NAcGalβ-PEGc)16.6-G5-(L4-DOX)13.4) conjugates. After confirming the conjugates' biocompatibility, flow cytometry studies show P1/P2 achieve 100% uptake into hepatic cancer cells at 30-60 × 10-9m particle concentration. This internalization correlates with cytotoxicity against HepG2 cells with 50% inhibitory concentration (IC50) values of 24.8, 1414.0, and 237.8 × 10-9m for free DOX, P1, and P2, respectively. Differences in cytotoxicity prompted metabolomics analysis to identify the intracellular release behavior of DOX. Results show that P1/P2 release alternative DOX metabolites than free DOX. Stable isotope tracer studies show that the different metabolites induce different effects on metabolic cycles. Namely, free DOX reduces glycolysis and increases fatty acid oxidation, while P1/P2 increase glycolysis, likely as a response to high oxidative stress. Overall, P1/P2 conjugates offer a platform drug delivery technology for improving hepatic cancer therapy.
authors.affiliation: Department of Materials Science and Engineering, University of Michigan, 2300 Hayward St., Ann Arbor, MI, 48109, USA.
authors.forename: Sibu P
authors.initials: SP
authors.lastname: Kuruvilla
authors.affiliation: Department of Biomedical Engineering, University of Michigan, 1101 Beal Avenue, Ann Arbor, MI, 48109, USA.
authors.forename: Gopinath
authors.initials: G
authors.lastname: Tiruchinapally
authors.affiliation: Department of Internal Medicine, University of Michigan Medical School, 1500 East Medical Center Drive, Ann Arbor, MI, 48109, USA.
authors.forename: Mahmoud
authors.initials: M
authors.lastname: ElAzzouny
authors.affiliation: Department of Biomedical Engineering, University of Michigan, 1101 Beal Avenue, Ann Arbor, MI, 48109, USA.|Department of Macromolecular Science and Engineering, University of Michigan, 2300 Hayward Avenue, Ann Arbor, MI, 48109, USA.
authors.forename: Mohamed E H
authors.initials: ME
authors.lastname: ElSayed
mesh_terms: D000116:Acetylgalactosamine / Q000378:metabolism*; D050091:Dendrimers / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D004317:Doxorubicin / Q000737:chemistry / Q000493:pharmacokinetics / Q000494:pharmacology; D016503:Drug Delivery Systems / Q000379:methods*; D056945:Hep G2 Cells; D006801:Humans; D008113:Liver Neoplasms / Q000188:drug therapy* / Q000378:metabolism* / Q000473:pathology
chemical_list: D050091:Dendrimers; D004317:Doxorubicin; D000116:Acetylgalactosamine
keywords: N-acetylgalactosamine ligands; PAMAM dendrimers; aromatic azolinkers; hepatocellular carcinoma; metabolomics