Fig. 2

In vitro growth of tumor spheres derived from prostatic and non-prostatic cancer cells under adherent two-dimensional (2D) and non-adherent agar-based three-dimensional (3D) culture conditions. a Representative images of three prostate cancer cell lines (LNCaP, VCaP, and DU145) and two non-prostatic cancer lines (HCT116 and HepG2) grown under the adherent 2D culture condition and the non-adherent 3D culture condition on agar-coated dishes. Bars: 200 μm. b Formation of 3D cultured spheres, derived from the primary human prostate cancer xenograft CWR22 and the 22Rv1 prostate cancer cell line derived from CWR22 xenograft [32], on 0.9% agar plates and commercial ultra-low attachment (ULA) plates. Bars: 200 μm. c Images show the tumor spheres formed by primary prostate cancer (PCa) tissues growing on 0.9% agar-coated dishes and ULA dishes for 2 weeks. Bars: 100 μm