Therefore, we analysed the effects of the HSP90-inhibitor 17-AAG as well as RNA-interference mediated inhibition of HSP90 on the tyrosine phosphorylation of STAT1, STAT3, STAT5, STAT6 and protein expression of Jak1, Jak2, Jak3 and Tyk2 in cHL cells. The gene discussed is JAK2; the disease is classic Hodgkin lymphoma.