Osteopontin/Matrixmetalloproteinase-9 Pathway Activation is Associated with Melanoma Progression

Previous studies strongly support the crucial role of OPN and MMP-9 in tumor progression through the regulation of highly integrated signaling events, including those critically dependent on MMPs bioavailability. The results of the present study, including analysis of well-defined clinical material including more than 100 blood samples from melanoma patients, show a significant correlation between OPN and both levels and activity of MMP-9 and that MMP-9 is strongly associated with positive sentinel lymph-node and tumour thickness. in this study, the levels of OPN and MMP9 were monitored in 18 melanoma cases who were followed-up. These 18 cases, at the first diagnosis (time 0) expressed both markers 3-to-6 fold higher than healthy controls. Three months after surgery, those levels were significantly reduced. These data were also confirmed by functional experiments conducted on PBMCs from 53 healthy donors and 29 melanoma patients that were cultured for 24 hours with and without OPN. Stimulation with OPN in PBMCs increased the production of MMP-9, especially in melanoma patients. These data suggested that the OPN/MMP-9 pathway is associated with transformation and progression.