ALK and anaplastic large cell lymphoma: Treatment of NPM-ALK(+) ALCL cells with the HSP90 inhibitor, 17-Allylamino-Demethoxygeldanamycin (17-AAG), resulted in decreased NPM-ALK expression, most likely due to the targeting of this protein for proteasomal degradation, but also to cell cycle arrest and to the induction of apoptosis [55,56].