A major component of vitamin E, α-tocopherol inhibits the anti-tumor activity of crizotinib against cells transformed by EML4-ALK

Yuki Uchihara, Takayuki Kidokoro, Kenji Tago, Tadahiko Mashino, Hiroomi Tamura, Megumi Tago

Research output: Contribution to journalArticle


Crizotinib is an inhibitor of anaplastic lymphoma kinase (ALK) and is of significant therapeutic benefit to patients with non-small cell lung cancer (NSCLC) harboring the EML4-ALK fusion gene. In the present study, we demonstrated that α-tocopherol, a major component of vitamin E, attenuated the effects of crizotinib independently of its anti-oxidant properties. α-Tocopherol significantly inhibited crizotinib-induced apoptosis in cells transformed by EML4-ALK. It also effectively attenuated the crizotinib-induced inhibition of EML4-ALK and its downstream molecules, STAT3 and ERK, and suppressed the inhibitory effects of crizotinib on EML4-ALK-mediated transformation in the focus formation assay. On the other hand, other members of the vitamin E family, namely, β-tocopherol, γ-tocopherol, δ-tocopherol, and α-tocotrienol, and a water-soluble analog of vitamin E, Trolox had no effects on the anti-tumor activity of crizotinib in cells transformed by EML4-ALK. Collectively, these results revealed the risk of the anti-tumor activity of crizotinib being attenuated when it is administrated in combination with vitamin E supplements containing α-tocopherol as a major component.

Original languageEnglish
Pages (from-to)1-9
Number of pages9
JournalEuropean Journal of Pharmacology
Publication statusPublished - 2018 Apr 15



  • Crizotinib
  • EML4-ALK
  • Vitamin E
  • α-tocopherol

ASJC Scopus subject areas

  • Pharmacology

Cite this