Differential regulation of glycosphingolipid biosynthesis in phenotypically distinct Burkitt's lymphoma cell lines

✍ Scribed by Samir Taga; Marianne Mangeney; Thomas Tursz; Joëlle Wiels

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: French
• Weight: 875 KB
• Volume: 61
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910610220

✦ Synopsis

Earlier studies have shown that Burkitt's lymphoma (BL) cell lines can be divided into 2 major groups: group I. which retain the original BL biopsy phenotype with expression of CD I0 and CD77 antigens and lack of B-cell activation markers, and group 111, which, after several in vitro passages, progress toward an "LCL-like" phenotype with loss of CDlO and CD77 expression and up-regulation of B-cell activation antigens. In previous studies we have shown that several glycolipid molecules constitute stage-specific antigens for B cells and that sequential shifts in the 3 major glycolipid series are observed during B-cell differentiation, these changes being mostly due to sequential activations of the corresponding glycosyltransferases. In the present work, 10 BL cell lines with group I or group 111 phenotype have been examined for cell surface expression of 5 glycolipid antigens (LacCer, GM3, Gb3/CD77, Gb4 and GM2). total glycolipid content and enzymatic activities of 4 glycosyltransferases (GM3. Gb3, Gb4 and GM2 synthetases). We now report that group I and group 111 BL cells differ in their glycolipid metabolism and express either mostly globoseries or ganglioseries compounds. Indeed, Gb3 is the major glycolipid of group I cells, whereas GM3 and GM2 are the 2 major components of group 111 cells, and these phenotypic differences are mainly due to differential activities of the corresponding glycosyltransferases: group I cells have high Gb3 synthetase activities and low or no GM3 and GM2 synthetase activities, whereas group 111 cells have high GM3 and GM2 synthetase activities and low Gb3 synthetase activities. Finally, we also show that, unlike LCL, group 111 BL cells do not synthesize Gb4.