Effects of Quercetin on Chronic Myeloid Leukemia Cell Line Resistant to Imatinib and Its Mechanism

OBJECTIVE: To explore the growth inhibitory effect of quercetin on imatinib-resistant chronic myeloid leukemia cell lines and to clarify its involved mechanisms. METHODS: The cell viability was detected by trypan blue Staining, percentage of apoptotic cells and cell cycle distribution were detected by flow cytometry, the protein expression was detected by Western blot. RESULTS: Both inhibitory effect of proliferation and apoptosis-inducing effect were similar between the imatinib-resistant and -sensitive cell lines treated with 25 µmol/L quercetin for 24 hours and with arrest of cell cycle at G2/M phase. Quercetin could not change the expression of BCR-ABL. The expression of γ-H2AX was markedly enhanced and the phosphorylation of JNK up-regulated by quercetin in both imatinib-resistant and imatinib-sensitive cell lines. CONCLUSION: The growth of imatinib-resistant cells can be inhibited by quercetin, and the apoptosis of cells can be induced by quercetin, which may be related to cell cycle arrest in G2/M. The DNA damage and up-regulation of p-JNK may be involved in these processes.