Fig. 2

Spheroid formation and proliferation analysis of CAMA-1 Rab31 overexpressing and vector control cells. A Both CAMA-1 Rab31 overexpressing and vector control cells formed spheroids in 3D culture, whereby Rab31 overexpressing cells resulted in much larger spheroids indicating a distinctly increased growth rate compared to vector control cells (p < 0.001). B Viable cells continuously convert the non-fluorescent substrate AlamarBlue into a fluorescent product (left panel), thereby allowing a quantitative measurement of cell numbers. Since the same cell number was plated out, Rab31 overexpressing cells display a faster growth rate as compared to vector control cells after 14 days. In the CyQuant assay (right panel), the content of DNA is measured by a non-fluorescent substrate, which upon intercalation into genomic DNA exhibits a strong fluorescence. The CyQuant proliferation assay of CAMA-1 cells shows a higher DNA content in Rab31 overexpressing as compared to vector control cells after 14 days, indicating a faster growth rate of Rab31 overexpressing cells. For both the AlamarBlue and the CyQuant assay a representative experiment of three independently performed biological replicates is depicted