We previously used T98G cells in our novel chick embryo brain tumor model and in vitro assays to reveal the roles of the adhesion protein L1CAM [49,50] and the fibroblast growth factor receptor (FGFR; a receptor for L1CAM) [31,33,36,37,51], both of which contain multiple disulfide bonds in their Ig-like domains [52,53], in cell motility, cell proliferation, and brain tissue invasion. This evidence concerns the gene L1CAM and brain neoplasm.