Fig. 2

Characteristics of a melanoma tri-culture spheroid model. Tri-culture spheroids were made by 3D cultivation of CCD-1137Sk fibroblasts for three days, followed by simultaneous addition of HaCaT keratinocytes and SK-MEL-28 melanoma cells, and then further culturing for another four days. HaCaT and SK-MEL-28 cells were labeled with CellTrackerRed CMPTX and CellTrackerGreen CMFDA dyes, respectively. As indicated, spheroids were incubated on day five after seeding either with 0.01 ‰ of DMSO as control (a) or 100 nM docetaxel in DMSO (b) for 48 h, then cryosectioned into 10-μm-thick slices and stained for Ki67, CAS3, CK10, CK14, and the basal membrane marker collagen-IV. Nuclei were labeled with Dapi. Images show representative confocal sections through these samples. In overlay panels, all immunostainings except for CK14 are depicted in red, SK-MEL28 cells in green, HaCaT cells or CK14 in yellow, and nuclei in blue. Scale bars: 100 μm