Data from Proapoptotic Function of Integrin β₃ in Human Hepatocellular Carcinoma Cells

<div>Abstract<p><b>Purpose:</b> This study evaluates the proapoptotic function of integrin β₃ in human hepatocellular carcinoma (HCC).</p><p><b>Experimental Design:</b> The expression of integrin β₃ in 67 HCC specimens paired with corresponding neighboring nontumorous tissue was studied by quantitative real-time PCR and Western blot. The proapoptotic function of integrin β₃ in SMMC-7721 human hepatoma cells overexpressing <i>ITGB3</i> (gene coding integrin β₃) was determined through colony formation, serum starvation, and anoikis assay.</p><p><b>Results:</b> Compared with neighboring pathologically normal liver tissue, ∼60% of the HCC specimens showed a significant down-regulated level of integrin β₃ expression. Transient expression of integrin β₃ in SMMC-7721 resulted in an enhanced level of apoptosis and suppression of colony formation. Cell growth inhibition on serum/ligand deprivation and incidences of anoikis were remarkably increased in SMMC-7721 with stable expression of integrin β₃ in comparison with vector control transfectants. In addition, expression of fibrinogen and vitronectin, two native ligands for integrin α_vβ₃ in liver, was inhibited, which was correlated with the decreased integrin β₃ expression. Replenishing these ligands to the starved SMMC-7721 stable transfectants effectively restored the proapoptotic function of integrin β₃.</p><p><b>Conclusions:</b> Down-regulation of integrin β₃ and its ligands in liver is related to the aggressive growth of HCC. Thus, reconstitution of integrin β₃ in HCC may be a potential therapeutic approach to inhibit aggressive growth of liver cancer.</p></div>