When NIH3T3 cells were transformed with the oncogenic Ras gene, cell spreading on fibronectin was greatly enhanced due to an increase in β1,6 GlcNAc branched tri- and tetra-antennary oligosaccharides in α5β1 integrin.29 Indeed, α5β1 integrin is related to tumor cell invasion and metastatic potential in osteosarcoma cells.36 Therefore, inhibition of osteosarcoma cell invasion was caused by RPN2 silencing via alteration of N-glycosylation status of this molecule. This evidence concerns the gene FN1 and osteosarcoma.