Anti-FUT4 monoclonal antibody, clone UG2 [Biotin]

The epithelial-mesenchymal transition (EMT) is an important factor in lung cancer metastasis, and targeting EMT is a potential therapeutic strategy. Fucosyltransferase IV (FUT4) and its synthetic cancer sugar antigen Lewis Y (LeY) was abnormally elevated in many cancers. In this study, a traditional Chinese medicine ginsenoside Rg3 was used to investigate whether its inhibition to EMT and invasion of lung cancer is by the glycobiology mechanism. We found that Rg3 treatment (25, 50, 100 mu g/ml) inhibited cell migration and invasion by wound-healing and transwell assays. Rg3 could significantly alter EMT marker proteins with increased E-cadherin, but decreased Snail, N-cadherin and Vimentin expression. Rg3 also down-regulated FUT4 gene and protein expression in lung cancer cells by qPCR, Western blot and immunofluorescence. After FUT4 down-regulated with shFUT4, EMT was obviously inhibited. Furthermore, the activation of EGFR through decreased LeY biosynthesis was inhibited, which blocked the downstream MAPK and NF-kappa B signal pathways. In addition, Rg3 reduced tumor volume and weight in xenograft mouse model, and significantly decreased tumor metastasis nodules in lung tissues by tail vein injection. In conclusion, Rg3 inhibits EMT and invasion of lung cancer by down-regulating FUT4 mediated EGFR inactivation and blocking MAPK and NF-kappa B signal pathways. Rg3 may be a potentially effective agent for the treatment of lung cancer.

Objective: To investigate whether Lewis Y (LeY) carried by integrin alpha v beta 3 influences integrin alpha v beta 3-mediated adhesion in an in vitro implantation model. Design: Laboratory research. Setting: Reproduction and glycobiology research laboratory. Intervention(s): Specific antibody blockage of LeY or integrin alpha v beta 3 and knockdown of FUT4 expression in RL95-2 cells by transient transfection of FUT4 siRNA. Main Outcome Measure(s): The expression of integrin alpha v beta 3 and LeY in both endometrial tissues and RL95-2 cells was measured. LeY carried by integrin alpha v beta 3 was identified by examining the immunoprecipitated integrin alpha v beta 3. The effect of knocking down FUT4 on the expression of integrin alpha v beta 3 and LeY and their impact on the adhesion of JAR cells to the RL95-2 cells were assessed. Result(s): Integrin alpha v beta 3 and LeY are expressed in both secretory-stage human endometrial tissue and in RL95-2 cells. Although integrin alpha v beta 3 carries LeY, knocking down FUT4 expression only reduces the expression of LeY but not of integrin alpha v beta 3. Knocking down FUT4, antibody blockade of LeY or integrin alpha v beta 3 consistently decreases the adhesion of JAR cells to the RL95-2 cells and prevents focal adhesion kinase (FAK) phosphorylation. Conclusion(s): LeY carried by integrin alpha v beta 3 plays a critical role on the attachment of JAR cells to the RL95-2 cells and activates integrin alpha v beta 3/FAK signaling. (Fertil Steril (R) 2011;95:1446-51. (C)2011 by American Society for Reproductive Medicine.)