title: Evaluation of interstitial protein delivery in multicellular layers model.
abstract: The limited efficacy of anticancer protein drugs is related to their poor distribution in tumor tissue. We examined interstitial delivery of four model proteins of different molecular size and bioaffinity in multicellular layers (MCL) of human cancer cells. Model proteins were tumor necrosis factor-related apoptosis-including ligand (TRAIL), cetuximab, RNase A, and IgG. MCLs were cultured in Transwell inserts, exposed to drugs, then cryo-sectioned for image acquisition using fluorescence microscopy (fluorescent dye-labeled TRAIL, RNase A, IgG) or immunohistochemistry (cetuximab). TRAIL and cetuximab showed partial penetration into MCLs, whereas RNase A and IgG showed insignificant penetration. At 10-fold higher dose, a significant increase in penetration was observed for IgG only, while cetuximab showed an intense accumulation limited to the front layers. PEGylated TRAIL and RNase A formulated in a heparin-Pluronic (HP) nanogel showed significantly improved penetration attributable to increased stability and extracellular matrix binding, respectively. IgG penetration was significantly enhanced with paclitaxel pretreatment as a penetration enhancer. The present study suggests that MCL culture may be useful in evaluation of protein delivery in the tumor interstitium. Four model proteins showed limited interstitial penetration in MCL cultures. Bioaffinity, rather than molecular size, seems to have a positive effect on tissue penetration, although high binding affinity may lead to sequestration in the front cell layers. Polymer conjugation and nanoformulation, such as PEGylation and HP nanogel, or use of penetration enhancers are potential strategies to increase interstitial delivery of anticancer protein drugs.
authors.affiliation: Department of Medical Life Sciences, College of Medicine, The Catholic University of Korea, Seoul 137-701, Korea.
authors.forename: Soo-Yeon
authors.initials: SY
authors.lastname: Kim
authors.forename: Tae Hyung
authors.initials: TH
authors.lastname: Kim
authors.forename: Jong Hoon
authors.initials: JH
authors.lastname: Choi
authors.forename: Kang Choon
authors.initials: KC
authors.lastname: Lee
authors.forename: Ki Dong
authors.initials: KD
authors.lastname: Park
authors.forename: Seung-Jin
authors.initials: SJ
authors.lastname: Lee
authors.forename: Hyo-Jeong
authors.initials: HJ
authors.lastname: Kuh
mesh_terms: D000911:Antibodies, Monoclonal / Q000378:metabolism; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism*; D001692:Biological Transport; D002463:Cell Membrane Permeability; D000068818:Cetuximab; D003110:Colonic Neoplasms / Q000378:metabolism*; D004337:Drug Carriers; D019073:HT29 Cells; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D008856:Microscopy, Fluorescence; D008970:Molecular Weight; D000080385:Nanogels; D017239:Paclitaxel / Q000494:pharmacology; D011092:Polyethylene Glycols / Q000737:chemistry; D011094:Polyethyleneimine / Q000737:chemistry; D011506:Proteins / Q000737:chemistry / Q000378:metabolism*; D012259:Ribonuclease, Pancreatic / Q000378:metabolism; D053221:TNF-Related Apoptosis-Inducing Ligand / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D004337:Drug Carriers; D007074:Immunoglobulin G; D000080385:Nanogels; D011506:Proteins; D053221:TNF-Related Apoptosis-Inducing Ligand; C413692:polyethylene glycol polyethyleneimine nanogel; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D012259:Ribonuclease, Pancreatic; D017239:Paclitaxel; D000068818:Cetuximab