Normal and aberrant expression of cytokines in neoplastic cells from chronic lymphocytic leukemias.

Molecular expression of cytokines and cytokine receptors associated with B-cell growth and differentiation was examined in cells from B-cell chronic lymphocytic leukemia patients using the PCR. These studies were undertaken in order to determine whether a particular cytokine could be associated with leukemic transformation in this disease. The precursor-lymphoid and pro-B, pre-B-cell growth factor, interleukin-7, was found to be expressed in 30 of 30 patients, whereas, it was not expressed in normal donor peripheral blood lymphocytes (0 of 8) or in purified B-cell subsets from normal individuals. IL-1 beta and IL-2 receptors, on the other hand, were expressed by B cells from both normal and B-CLL patients. Other cytokine and cytokine receptors examined were not consistently expressed by all donors. Thus IL-7 was found to be the only cytokine tested that was expressed in CLL cells and not in normal cells.