CD44V6 EXPRESSION IN NON-HODGKINS-LYMPHOMA - AN ASSOCIATION WITH LOW HISTOLOGICAL GRADE AND POOR-PROGNOSIS

The family of CD44 glycoproteins has diverse functions in cell-cell an d cell-matrix interactions. The standard form of CD44 is of importance in the dissemination of lymphoma, whereas the clinical significance o f the variant exon v6-containing forms of CD44 (CD44v6) is not known. The expression of different forms of CD44 was investigated by using an tibodies against the constant part of CD44 (CD44c) and CD44v6 in 56 pr imary and 17 recurrent non-Hodgkin's lymphomas and correlated with sev eral clinicopathological parameters and with prognosis. Fifty-seven pe r cent of the primary non-Hodgkin's lymphomas expressed CD44v6 and 73 per cent expressed the constant epitope. Expression of both CD44c and CD44v6 was associated with low histological grade of malignancy. CD44c expression was associated with a low cellular proliferation rate as a ssessed by DNA flow cytometry. Of several factors tested, high express ion of the variant from v6 was the only factor that was associated wit h unfavourable recurrence-free survival (P=0.04). We conclude that CD4 4v6 is associated with a low histological grade, but, on the other han d, with an unfavourable outcome, which suggests that the combination o f CD44V6 and histological grading may form a particularly strong progn ostic parameter in non-Hodgkin's lymphoma.