IL6 and lymphoproliferative disorders.

Interleukin 6 has pleiotropic effects on cells from various lineages. Several data indicate that it may play a critical role in the development of multiple myeloma by an autocrine or parcrine stimulation pathway. For instance, we showed that oligodeoxynucleotides antisens of IL6 mRNA were capable to decrease the proliferation of two different myeloma cell lines. In Waldenström's macroglobulinemia, at the initial stage of the disease, there is an autocrine differentiation pathway which is dependent of the secretion of IL6 by tumor cells. IL6 may also be implicated in the pathogenesis of some other lymphoid malignancies such as follicular lymphomas or large cell lymphomas. Its role in the systemic symptoms of Castleman disease has been clearly established.