Figure 5.

MSC-derived MMP13 promotes cancer cell migration in a three-dimensional spheroid model. PDVA cells alone (PDVA) or mixed with MSC (PDVA + MSC) were embedded as spheroids in a type 1 collagen matrix for 48 hours. MSCs were derived from (A) GFP mice, (C) wild-type mice (MSC WT), or (D) MMP13-deficient mice (MSC KO). (A) Combination of fluorescent and phase contrast images showed that GFP signal is detected in the spheroids composed of PDVA and GFP⁺ MSC but not in cells spreading out of the spheroid. Optical microscopic observation of spheroids composed of PDVA alone (B) or confronted to MSC expressing (C) or not MMP13 (D). (E) Quantification of tumor cell migration area of PDVA cells cultured alone or mixed with MSC WT or MSC KO. (F) Quantification of PDVA cell migration area cultured alone or mixed with MSC, in the presence of BB94 or control.