Masset, Anne[Université de Liège - ULg > Département des sciences biomédicales et précliniques > Biologie cellulaire et moléculaire appliquée à l'homme >]
Foidart, Jean-Michel[Université de Liège - ULg > Département des sciences cliniques > Gynécologie - Obstétrique - Labo de biologie des tumeurs et du développement >]
Noël, Agnès[Université de Liège - ULg > Département des sciences biomédicales et précliniques > Biologie cellulaire et moléculaire appliquée à l'homme >]
[en] Plasminogen activator inhibitor-1 is known to play a paradoxical positive role in tumor angiogenesis, but its contribution to metastatic spread remains unclear. We studied the impact of PAI-1 deficiency in a transgenic mouse model of ocular tumors originating from retinal epithelial cells and leading to brain metastasis (TRP-1/SV40 Tag mice). PAI-1 deficiency did not affect primary tumor growth or vascularization, but was associated with a smaller number of brain metastases. Brain metastases were found to be differentially distributed between the two genotypes. PAI-1-deficient mice displayed mostly secondary foci expanding from local optic nerve infiltration, whereas wild-type animals displayed more disseminated nodules in the scissura and meningeal spaces. SuperArray GEArray analyses aiming to detect molecules potentially compensating for PAI-1 deficiency demonstrated an increase in fibroblast growth factor-1 (FGF-1) gene expression in primary tumors, which was confirmed by RT-PCR and western blotting. Our data provide the first evidence of a key role for PAI-1 in a spontaneous model of metastasis, and suggest that angiogenic factors, such as FGF-1, may be important for primary tumor growth and may compensate for the absence of PAI-1. They identify PAI-1 and FGF-1 as important targets for combined anti-tumor strategies.
FP7 ; 201279 - MICROENVIMET - Understanding and fighting metastasis by modulating the tumour microenvironment through interference with the protease network.