According to proteomic analyses of ocular samples from individuals with KC, it is possible to propose a proteomic profile involved in the pathogenesis of this disease, which includes collagen types I and IV, fibronectin (FN1), vitronectin, MMP-9, TIMP-1, IL-6, TNF-α, annexin, SOD1, GPX1, KRT3, decorin, and HSP70. The gene discussed is MMP9; the disease is keratoconus.