675 The phosphorylation of CD147 by Fyn plays a critical role in melanoma cell growth and metastasis

Abstract

CD147, also known as extracellular matrix metalloproteinase inducer (EMMPRIN), is a transmembrane glycoprotein that is highly expressed in tumor cells, particularly melanoma cells, and plays critical roles in tumor cell metastasis through the regulation of matrix metalloprotease (MMP) expression. Studies have demonstrated that CD147 could promote melanoma progression through post-translational modification, such as glycosylation. However, the role of phosphorylation of CD147 in melanoma remains unclear. In this study, we identified Fyn, a member of Src family that regulates diverse physiological processes, as a novel interacting protein of CD147. Our findings demonstrated that Fyn directly phosphorylates CD147 at Y140 and Y183. Two phosphospecific antibodies against Y140 and Y183 were developed to validate the phosphorylation of CD147 by Fyn. Moreover, the CD147-FF (Y140F/Y183F) mutation impaired the interaction between CD147 and GnT-V, leading to decreased CD147 glycosylation and membrane recruitment. In addition, CD147-FF significantly blocked MMP-9 expression as well as cell migration. Moreover, we found that Fyn is overexpressed in melanoma clinical tissues as well as in melanoma cell lines. Knockdown of Fyn expression markedly attenuated the malignant phenotype of melanoma cells in vitro and in vivo through downregulation of CD147 phosphorylation, indicating that Fyn/CD147 is a potential target molecule in melanoma treatment. Finally, through virtual screening, we identified amodiaquine as a potential inhibitor targeting the Fyn/CD147 axis. amodiaquine treatment dramatically inhibited the phosphorylation of CD147 by Fyn, thus attenuating melanoma cell growth and invasion in vitro and in vivo, suggesting that amodiaquine is a promising inhibitor for melanoma treatment. In conclusion, our findings showed that the Fyn/CD147 axis plays an essential role in melanoma cell metastasis and growth and that amodiaquine, which targets this axis, is a promising inhibitor for melanoma treatment.