title: Engineering a scaffold-free 3D tumor model for in vitro drug penetration studies.
abstract: Three-dimensional (3D) in vitro cultures are recognized for recapitulating the physiological microenvironment and exhibiting high concordance with in vivo conditions. In cancer research, the multi-cellular tumor spheroid (MCTS) model is an established 3D cancer model that exhibits microenvironmental heterogeneity close to that of tumors in vivo. However, the established process of MCTS formation is time-consuming and often uncontrolled. Here, we report a method for engineering MCTS using a transient inter-cellular linker which facilitates cell-cell interaction. Using C3A cells (a hepatocellular carcinoma cell line) as a model, we formed linker-engineered spheroids which grew to a diameter of 250 microm in 7 days, as compared to 16 days using conventional non-adherent culture. Seven-day old linker-engineered spheroids exhibited characteristics of mature MCTS, including spheroid morphology, gene expression profile, cell-cell interaction, extracellular matrix secretion, proliferation and oxygen concentration gradients, and cellular functions. Linker-engineered spheroids also displayed a resistance to drug penetration similar to mature MCTS, with dose-dependent extracellular accumulation of the drug. The linker-engineered spheroids thus provide a reliable accelerated 3D in vitro tumor model for drug penetration studies.
authors.affiliation: Institute of Bioengineering and Nanotechnology, Agency for Science, Technology and Research (A* STAR), The Nanos, 31 Biopolis Way, Singapore 138669, Singapore.
authors.forename: Siew-Min
authors.initials: SM
authors.lastname: Ong
authors.forename: Ziqing
authors.initials: Z
authors.lastname: Zhao
authors.forename: Talha
authors.initials: T
authors.lastname: Arooz
authors.forename: Deqiang
authors.initials: D
authors.lastname: Zhao
authors.forename: Shufang
authors.initials: S
authors.lastname: Zhang
authors.forename: Tiehua
authors.initials: T
authors.lastname: Du
authors.forename: Martin
authors.initials: M
authors.lastname: Wasser
authors.forename: Danny
authors.initials: D
authors.lastname: van Noort
authors.forename: Hanry
authors.initials: H
authors.lastname: Yu
mesh_terms: D001681:Biological Assay / Q000379:methods*; D006528:Carcinoma, Hepatocellular / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D018929:Cell Culture Techniques / Q000379:methods; D045744:Cell Line, Tumor; D004317:Doxorubicin / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D006801:Humans; D010599:Pharmacokinetics; D018874:Spheroids, Cellular / Q000187:drug effects / Q000378:metabolism*; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D004317:Doxorubicin