Selma Maacha1, Océane Anezo1, Malika Foy1, Géraldine Liot1, Laurence Mery1, Cécile Laurent2, Xavier Sastre-Garau3, Sophie Piperno-Neumann4, Nathalie Cassoux5, Nathalie Planque6, Simon Saule1. 1. Institut Curie, PSL Research University, Centre National de La Recherche Scientifique (CNRS), Institut National de la Santé Et de la Recherche Médicale (INSERM), Unité Mixte de Recherche 3347 (UMR), Unité 1021 Orsay, France 2Université Paris Sud, Universi. 2. Residual Tumor & Response to Treatment Lab, Institut Curie - Translational Research Department, Paris, France. 3. Tumor Biology Department, Institut Curie, Paris, France. 4. Department of Medical Oncology, Institut Curie, Paris, France. 5. Department of Surgical Oncology, Institut Curie, Paris, France. 6. Institut Curie, PSL Research University, Centre National de La Recherche Scientifique (CNRS), Institut National de la Santé Et de la Recherche Médicale (INSERM), Unité Mixte de Recherche 3347 (UMR), Unité 1021 Orsay, France 7Université Paris Diderot, Sorb.
Abstract
PURPOSE: To study PTP4A3 phosphatase and MMP14 metalloprotease synergy in uveal melanoma aggressiveness. METHODS: Cell membrane localization of matrix metalloprotease 14 (MMP14) in uveal melanoma cells expressing protein tyrosine phosphatase A3 (PTP4A3) was assessed by flow cytometry or immunohistochemistry. The vesicular trafficking of MMP14 in the presence of PTP4A3 was evaluated in OCM-1 cells expressing either the wild-type or mutated phosphatase. Finally, MMP14 localization at the cell membrane of OCM-1 cells was impaired using RNA interference, and the PTP4A3-related migration in vitro and invasiveness in vivo of the treated cells were evaluated. RESULTS: We found that the membrane-anchored MMP14 is enriched at the cell surface of OCM-1 cells, patient-derived xenograft cells, and human primary uveal melanoma tumors expressing PTP4A3. Moreover, we show that PTP4A3 and MMP14 colocalize and that the vesicular trafficking of MMP14 is faster in the presence of active PTP4A3. Finally, we demonstrate that inhibition of MMP14 expression in uveal melanoma cells expressing PTP4A3 impairs their migration in vitro and invasiveness in vivo. CONCLUSIONS: Our observations indicate that PTP4A3 increases cell membrane accumulation of MMP14 as a result of increased cellular trafficking of the metalloprotease. We also show that downregulation of MMP14 expression reduced PTP4A3-induced cell migration and invasiveness. Taken together, our findings suggest that PTP4A3-related subcellular localization of MMP14 is an important event in metastasis induction.
PURPOSE: To study PTP4A3 phosphatase and MMP14 metalloprotease synergy in uveal melanoma aggressiveness. METHODS: Cell membrane localization of matrix metalloprotease 14 (MMP14) in uveal melanoma cells expressing protein tyrosine phosphatase A3 (PTP4A3) was assessed by flow cytometry or immunohistochemistry. The vesicular trafficking of MMP14 in the presence of PTP4A3 was evaluated in OCM-1 cells expressing either the wild-type or mutated phosphatase. Finally, MMP14 localization at the cell membrane of OCM-1 cells was impaired using RNA interference, and the PTP4A3-related migration in vitro and invasiveness in vivo of the treated cells were evaluated. RESULTS: We found that the membrane-anchored MMP14 is enriched at the cell surface of OCM-1 cells, patient-derived xenograft cells, and human primary uveal melanoma tumors expressing PTP4A3. Moreover, we show that PTP4A3 and MMP14 colocalize and that the vesicular trafficking of MMP14 is faster in the presence of active PTP4A3. Finally, we demonstrate that inhibition of MMP14 expression in uveal melanoma cells expressing PTP4A3 impairs their migration in vitro and invasiveness in vivo. CONCLUSIONS: Our observations indicate that PTP4A3 increases cell membrane accumulation of MMP14 as a result of increased cellular trafficking of the metalloprotease. We also show that downregulation of MMP14 expression reduced PTP4A3-induced cell migration and invasiveness. Taken together, our findings suggest that PTP4A3-related subcellular localization of MMP14 is an important event in metastasis induction.