title: SMT-A07, a 3-(Indol-2-yl) indazole derivative, induces apoptosis of leukemia cells in vitro.
abstract: N-(2-(1H-indazol-3-yl)-1H-pyrrolo[3,2-b]pyridin-5-yl)-4-chloro-N-methylbenzamide (SMT-A07) is a novel 3-(Indol-2-yl) indazole derivative. The anticancer activities in vitro and the cell apoptosis-induction abilities of SMT-A07 on human leukemia HL60 and NB4 cell lines were investigated in this study. The results of MTT assay showed SMT-A07 was a potential and highly efficient antitumor compound with IC(50) values ranging from 0.09 to 1.19 μM in five leukemia cell lines. SMT-A07 treatment for 24 h caused the increment of apoptosis rate from 6.88 to 49.72% in HL60 cells and from 8.72 to 56.28% in NB4 cells by flow cytometry analysis. Agarose gel electrophoresis showed DNA fragmentation that appeared after cells were exposed to SMT-A07. After SMT-A07 incubation, DAPI staining revealed the presence of DNA fragmentation, and perinuclear apoptotic body. SMT-A07 also resulted in a loss of ΔΨm in both HL60 and NB4 cells by JC-1 staining. Moreover, apoptosis-related proteins were examined by western blotting to explore the mechanism of its cytotoxicity. SMT-A07 exposure caused down-regulation and cleavage of procaspase-8, procaspase-3, Bid, PARP and up-regulation of cleaved caspase-8, cleaved caspase-3, PARP (Cleaved Fragment). In addition, the presence of pan-caspase inhibitor BOC-D-FMK prevented cells from caspase-3 activation, PARP cleavage, and subsequent apoptosis. Our study demonstrates that SMT-A07 displays an apparent antitumor activity with extensive anti-leukemia spectrum, and SMT-A07 can induce the apoptosis of HL60 and NB4 cells activation of the caspase cascade, which deserves further development.
authors.affiliation: Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou, 310058, China.
authors.forename: Shijing
authors.initials: S
authors.lastname: Qian
authors.forename: Ji
authors.initials: J
authors.lastname: Cao
authors.forename: Yan
authors.initials: Y
authors.lastname: Yan
authors.forename: Maotang
authors.initials: M
authors.lastname: Sun
authors.forename: Hong
authors.initials: H
authors.lastname: Zhu
authors.forename: Yongzhou
authors.initials: Y
authors.lastname: Hu
authors.forename: Qiaojun
authors.initials: Q
authors.lastname: He
authors.forename: Bo
authors.initials: B
authors.lastname: Yang
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D001549:Benzamides / Q000494:pharmacology* / Q000627:therapeutic use; D020169:Caspases / Q000378:metabolism*; D045744:Cell Line, Tumor; D053938:DNA Fragmentation; D018922:HL-60 Cells; D006801:Humans; D007191:Indazoles / Q000494:pharmacology* / Q000627:therapeutic use; D020128:Inhibitory Concentration 50; D007938:Leukemia / Q000188:drug therapy* / Q000473:pathology
chemical_list: D001549:Benzamides; D007191:Indazoles; C556664:N-(2-(1H-indazol-3-yl)-1H-pyrrole(3,2-b)pyridin-5-yl)-4-chloro-N-methylbenzamide; D020169:Caspases