CD26 in T-cell lymphomas: a potential clinical role?

T-cell non-Hodgkin's lymphomas are a heterogeneous group of diseases that differ markedly in terms of their clinical behavior and prognosis. In recently developed classification systems, the sites of initial disease presentation assume a more prominent role in subgroup delineation. CD26, a structure with an integral role in human T-cell function that serves as the binding protein to adenosine deaminase, has been identified recently as a potential marker for certain aggressive T-cell lymphomas. To translate our knowledge of the basic biology of CD26/adenosine deaminase into clinical practice and to develop specific treatment for T-cell lymphomas based on CD26 expression, we, at M. D. Anderson Cancer Center, have initiated a phase II trial. This trial will evaluate the effect of pentostatin (Nipent), a potent adenosine deaminase inhibitor with known efficacy against T-cell malignancies, on relapsed/refractory T-cell lymphomas in relation to CD26 expression.