Figure 3

The production and secretion of matrix metalloproteinases (MMPs) was increased in UCX® cells within spheroids. Gelatin zymography of conditioned medium produced by UCX® cells in two-dimensional (CM2D; lanes 1 and 2) or three-dimensional (CM3D; lanes 3 and 4) culture conditions. (A) Zymogram analysis demonstrates that different culture conditions result in variations of the content of produced MMPs. All the samples display a high molecular weight (~130 kDa) set of bands depicting MMP complexes, and also single MMPs such as pro-MMP-9 (~92 kDa), MMP-9 (~82 kDa), pro-MMP-2 (~72 kDa), MMP-2 (~66 kDa) and an additional low molecular weight (~45 kDa) set of bands that could refer to other MMPs with residual proteolytic activity in gelatin substrates (possibly MMP-1 or −13). (B) Quantification of proteolytic bands by densitometric analysis of three independent experiments (n = 3) indicates that UCX® seeded under three-dimensional conditions produce higher relative amounts of MMP-9 and MMP-2, both the zymogen and the active isoform. ***P < 0.001.