RESUMO
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<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<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.
