Fig. 4

Increases in chemo-resistances against anticancer agents and radio-resistances in 3D cultures of HOSS1 cells. a: RT-qPCR analysis of drug resistance-related genes (ATP-binding cassette transporters) in 3D and 2D cultures. Values in 2D cultures for each gene were defined as 1. Results are the mean ± SD (n = 3) with Student’s-t test. b: Western blot analysis of HOSS1 cells in 3D and 2D cultures. c, d: Clonogenic survival of 3D- and 2D-cultured cells exposed to various concentrations of Doxorubicin (10, 100 nM, 1 μM, and 10 μM), Gemcitabine (1, 10, 100, and 1000 μM), and Docetaxel (1, 10, 100, and 1000 μM) (c) or X-ray doses (2, 4, 6, and 8 Gy) (d) at 24 hours after plating. ^* P < 0.05; ^** P < 0.01 vs. respective 2D-cultured cells. Results of a representative independent experiment of three are shown