Issn Print: 0192-8562
Publication Date: 1997/07/01
#504 Neuroblastomas diagnosed by screening exhibit a characteristic ganglioside pattern
Excerpt
Neuroblastoma in infants identified by urinary catecholamine screening appears to represent a clinically and biologically distinct group, with favorable biologic features and excellent prognosis, in contrast to the much poorer overall outcome in clinically diagnosed neuroblastoma. The membrane glycosphingolipids, gangliosides, constitute one biological factor influencing experimental tumor formation. In neuroblastoma, qualitative and quantitative differences in ganglioside composition and shedding correlate with outcome in clinically diagnosed disease. Furthermore, striking ganglioside variability has been observed in neuroblastoma and the related tumors ganglioneuroblastoma and ganglioneuroma. We hypothesized that distinct and specific gangliosides may characterize the clinically silent tumors identified by screening. To examine this, gangliosides were purified from 41 pretreatment samples obtained through the Quebec Neuroblastoma Screening Project, a controlled, population-based, prospective trial of early detection and treatment of neuroblastoma. 20 of the infants were diagnosed by screening for urinary catecholamines at either 3 weeks or 6 months of age, and 21 were diagnosed clinically (mean age 9 months). Ganglioside analysis by HPTLC densitometry revealed the screened tumors to have a distinct, reproducible ganglioside pattern. This pattern was rich in “b series” gangliosides (GD3, GD2, GDlb, GTlb normally prominent in fetal tissues), was high in complex polysialyated gangliosides, and was low in “a series” gangliosides including the monosialogangliosides GM3 and GM2 and the normal brain gangliosides GM1 and GDla. In contrast, the clinically diagnosed tumors had a much more heterogeneous combination of features, wherein a number of samples displayed predominance of “a series” gangliosides; others were rich in complex gangliosides; while still others had an array of gangliosides arising through both metabolic pathways. Of note, the ganglioside pattern of a number of these clinically diagnosed tumors mirrored the specific, uniform pattern found in the screened tumors, suggesting a biologic link between clinically favorable disease in children <1 year and clinically silent disease. These data suggest a specific ganglioside pattern may characterize neuroblastoma tumors with favorable prognosis. Analyses of the gangliosides of tumors from older children, and of disease outcome, are in progress to confirm the relationship between ganglioside metabolism and tumor behavior suggested by our findings.
Facebook
Twitter
LinkedIn
Email
