Curcumin derivative C817 inhibits proliferation of imatinib-resistant chronic myeloid leukemia cells with wild-type or mutant Bcr-Abl in vitro.
OBJECTIVE
To find new kinase inhibitors that overcome the imatinib resistance in treatment of chronic myeloid leukemia (CML), we synthesized C817, a novel derivative of curcumin, and tested its activities against wild-type (WT) and imatinib-resistant mutant Abl kinases, as well as in imatinib-sensitive and resistant CML cells in vitro.


METHODS
32D cells harboring WT or mutant Abl kinases (nucleotide binding P-loop mutants Q252H, Y253F, and imatinib contact residue mutant T315I), as well as K562/G01 cells (with whole Bcr-Abl gene amplication) were tested. Kinase activity was measured using Kinase-Glo Luminescent Kinase Assay Platform in recombinant WT and mutant (Q252H, Y253F, and T315I) Abl kinases. Cell proliferation and apoptosis were examined using MTT assay and flow cytometry, respectively. The phosphorylation levels of Bcr-Abl initiated signaling proteins were analyzed using Western blotting. Colony forming units (CFU) growth and long term culture-initiating cells (LTC-ICs) were used to test the effects of C817 on human leukemia progenitor/stem cells.


RESULTS
C817 potently inhibited both WT and mutant (Q252H, Y253F, and T315I) Abl kinase activities in a non-ATP competitive manner with the values of IC₅₀ at low nanomole levels. In consistent with above results, C817 suppressed the growth of both imatinib-sensitive and resistant CML cells, including wild-type K562, K562/G01, 32D-T315I, 32D-Q252H, and 32D-Y253F cells with the values of IC₅₀ at low micromole levels. C817 (0.5 or 1 μmol/L) dose-dependently inhibited the phosphorylation of Bcr-Abl and downstream proteins STAT-5 and CrkL in imatinib-resistant K562/G01 cells. Furthermore, C817 significantly suppressed CFU growth and LTC-ICs, implicating that C817 could eradiate human leukemia progenitor/stem cells.


CONCLUSIONS
C817 is a promising compound for treatment of CML patients with Bcr-Abl kinase domain mutations that confer imatinib resistance.
1] Department of Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [2] Institute of Materia Medica, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [3] Fuijan Key Laboratory of Natural Medicine Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China.
Li-xian
LX
Wu
1] Institute of Materia Medica, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [2] Fuijan Key Laboratory of Natural Medicine Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China.
Ying
Y
Wu
1] Department of Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [2] Institute of Materia Medica, School of pharmacy, Fujian Medical University, Fuzhou 350004, China.
Rui-jia
RJ
Chen
1] Institute of Materia Medica, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [2] Fuijan Key Laboratory of Natural Medicine Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [3] Department of pharmacochemistry, School of pharmacy, Fujian Medical University, Fuzhou 350004, China.
Yang
Y
Liu
1] Department of Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [2] Institute of Materia Medica, School of pharmacy, Fujian Medical University, Fuzhou 350004, China.
Li-sen
LS
Huang
Shanghai Institute of Materia Medica, Shanghai 201203, China.
Li-guang
LG
Lou
Fujian Institute of Hematology, Union Hospital, Fujian Medical University, Fuzhou 350001, China.
Zhi-hong
ZH
Zheng
Fujian Institute of Hematology, Union Hospital, Fujian Medical University, Fuzhou 350001, China.
Yuan-zhong
YZ
Chen
1] Department of Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [2] Institute of Materia Medica, School of pharmacy, Fujian Medical University, Fuzhou 350004, China [3] Fuijan Key Laboratory of Natural Medicine Pharmacology, School of pharmacy, Fujian Medical University, Fuzhou 350004, China.
Jian-hua
JH
Xu
D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D001549:Benzamides / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects*; D003474:Curcumin / Q000031:analogs & derivatives / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D019008:Drug Resistance, Neoplasm / Q000235:genetics*; D016044:Fusion Proteins, bcr-abl / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism; D020022:Genetic Predisposition to Disease; D006801:Humans; D000068877:Imatinib Mesylate; D020014:K562 Cells; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000201:enzymology / Q000235:genetics* / Q000473:pathology*; D009154:Mutation; D014411:Neoplastic Stem Cells / Q000187:drug effects / Q000201:enzymology / Q000473:pathology; D010641:Phenotype; D010766:Phosphorylation; D010879:Piperazines / Q000494:pharmacology*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011743:Pyrimidines / Q000494:pharmacology*
D000972:Antineoplastic Agents, Phytogenic; C581634:BCR-ABL1 fusion protein, human; D001549:Benzamides; C000595584:C817 curcumin derivative; D010879:Piperazines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D016044:Fusion Proteins, bcr-abl; D003474:Curcumin