Loss of heterozygosity in the Hodgkin-Reed Sternberg cell line L1236

Hodgkin-Reed Sternberg cells are derived from germinal centre B-cells in mo st cases. Somatic mutations affecting their rearranged immunoglobulin genes were detected, rendering potential functional rearrangements non-functiona l. Under physiological conditions such cells would be designated to undergo apoptosis within the germinal centre. In search for the specific transform ing event that prevents Hodgkin-Reed Sternberg cells from programmed cell d eath, cytogenetic analyses were broadly performed but did not reveal specif ic chromosomal aberrations. Analysis of these cells on the molecular lever is difficult to perform due to the scarcity of the cells in the lymphoma ti ssue and the given limitations of in situ studies. To overcome these limita tions, the cell line L1236, known to be derived from Hodgkin-Reed Sternberg cells in situ, was chosen for allelotype analysis. Using a panel of micros atellite loci assigned to nearly all chromosomal arms, regions of loss of h eterozygosity were detected on chromosomal arms 6p, 9q and 17p. The size of lost segments was estimated by amplification of additional microsatellite loci mapped to the respective regions. Further analyses of single Hodgkin-R eed Sternberg cells will reveal whether LOH affecting these regions is a re current event in HD and to which extent the smallest commonly affected regi on can be estimated. (C) 2001 Cancer Research Campaign.