Open AccessAlpha-tocopherol attenuates the anti-tumor activity of crizotinib against cells transformed by NPM-ALK
Author(s) -
Yuki Uchihara,
Fumihito Ueda,
Kenji Tago,
Yosuke Nakazawa,
Tomoyuki Ohe,
Tadahiko Mashino,
Shigenobu Yokota,
Tadashi Kimura,
Hiroomi Tamura,
Megumi FunakoshiTago
Publication year - 2017
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0183003
Subject(s) - crizotinib , anaplastic lymphoma kinase , cancer research , apoptosis , chemistry , alk inhibitor , stat protein , stat3 , medicine , biochemistry , pleural effusion , malignant pleural effusion
Anaplastic large cell lymphomas (ALCL) are mainly characterized by harboring the fusion protein nucleophosmin-anaplastic lymphoma kinase (NPM-ALK). The ALK inhibitor, crizotinib specifically induced apoptosis in Ba/F3 cells expressing NPM-ALK by inhibiting the activation of NPM-ALK and its downstream molecule, signal transducer and activator of transcription factor 3 (STAT3). We found that α-tocopherol, a major component of vitamin E, attenuated the effects of crizotinib independently of its anti-oxidant properties. Although α-tocopherol suppressed the inhibitory effects of crizotinib on the signaling axis including NPM-ALK and STAT3, it had no influence on the intake of crizotinib into cells. Crizotinib also directly inhibited the kinase activity of NPM-ALK; however, this inhibitory effect was not altered by the co-treatment with α-tocopherol. Whereas the nuclear localization of NPM-ALK was disappeared by the treatment with crizotinib, the co-treatment with α-tocopherol swept the effect of crizotinib and caused the localization of NPM-ALK in nucleus. The administration of α-tocopherol attenuated the anti-tumor activity of crizotinib against NPM-ALK-provoked tumorigenesis in vivo . Furthermore, the α-tocopherol-induced inhibition of crizotinib-caused apoptosis was also observed in NPM-ALK-positive cells derived from ALCL patients, namely, SUDHL-1 and Ki-JK. Collectively, these results not only revealed the novel mechanism underlying crizotinib-induced apoptosis in NPM-ALK-positive cells, but also suggest that the anti-tumor effects of crizotinib are attenuated when it is taken in combination with vitamin E.