Abstract 1616: Galectin-4 interferes with the integrin β4/Src/FAK cascade and attenuates metastasis in urothelial carcinoma

Abstract

Abstract Galectin-4 (Gal-4), a multifunctional lectin, is presented at both intracellular and extracellular sites. Recent studies have shown that Gal-4 plays certain role in attenuating cancer progression and metastasis. We have also observed that patients with urothelial carcinoma (UC) with the lower Gal-4 expression were at higher grade and stage. In addition, the Gal-4 expression is inversely associated with lymph node invasion and prognosis. Since how Gal-4 attenuates the cancer metastasis in UC has not been well investigated, the goal of the present study is to understand the role of Gal-4 in UC progression. We ectopically expressed Gal-4 in UC cells and found that increased Gal-4 significantly inhibits cell proliferation, colony formation, migration, and invasion. We also demonstrated that Gal-4 overexpression leads to a significant decrease the adhesion of UC cells to the basement membrane substrate laminin. Mechanistically, we found that Gal-4 overexpression significantly reduces the expression of the laminin receptor integrin α6β4. Besides to downregulation of integrin β4, Gal-4 overexpression also reduces phosphorylation of Src and focal adhesion kinase (FAK) and promotes anoikis. Together, the present results revealed that Gal-4 reduces the metastasis activity of UC cells by interfering integrin β4/Src/FAK cascade, which are of essential to prevent the suspended cells from anoikis. These results suggest that Gal-4 could be considered as a pivotal factor in the migration and invasion of UC cells. Key words: Galectin-4, integrin β4, migration, invasion, metastasis, anoikis, urothelial cancer Citation Format: Li-Fang Lin, Meei-Maan Wu, Te-Chang Lee. Galectin-4 interferes with the integrin β4/Src/FAK cascade and attenuates metastasis in urothelial carcinoma. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1616.