TY - JOUR T1 - Effects of Vitamin K<sub>3</sub> and K<sub>5</sub> on Daunorubicin-resistant Human T Lymphoblastoid Leukemia Cells JF - Anticancer Research JO - Anticancer Res SP - 6041 LP - 6048 VL - 35 IS - 11 AU - ERI NAKAOKA AU - SACHIKO TANAKA AU - KENJI ONDA AU - KENTARO SUGIYAMA AU - TOSHIHIKO HIRANO Y1 - 2015/11/01 UR - http://ar.iiarjournals.org/content/35/11/6041.abstract N2 - Background/Aim: Anticancer efficacy of vitamin K derivatives on multidrug-resistant cancer cells has been scarcely investigated. Materials and Methods: The effects of vitamins K3 and K5 on proliferation of human leukemia MOLT-4 cells and on daunorubicin-resistant MOLT-4/DNR cells were estimated by a WST assay. Apoptotic cells were detected by Annexin V and propidium iodide staining, followed by flow cytometry. Results: Vitamins K3 and K5 significantly inhibited proliferation of leukemic cells at 10 and 100 μM (p&lt;0.05), and these effects were almost equally observed in both MOLT-4 and MOLT/DNR drug-resistant cells. Vitamin K3 induced cell apoptosis at 10 and 100 μM in both MOLT-4 and MOLT-4/DNR cells (p&lt;0.05). Vitamin K5 also increased apoptotic cells, while rather inducing necrotic cell death. Conclusion: Vitamins K3 and K5 suppress MOLT-4 and MOLT-4/DNR cell-proliferation partially through induction of apoptosis, and these vitamin derivatives can overcome drug resistance due to P-glycoprotein expression. ER -