A novel synthetic 2-(3-methoxyphenyl)-6,7-methylenedioxoquinolin-4-one             arrests the G2/M phase arrest via Cdc25c and induces apoptosis through caspase-             and mitochondria-dependent pathways in TSGH8301 human bladder cancer cells.
2-(3-methoxyphenyl)-6,7-methylenedioxoquinolin-4-one (MMEQ) is a novel synthesized             compound, and this study investigated the effects of MMEQ on molecular signal             pathways of the induction of apoptosis in TSGH8301 human bladder cancer cells.             The studies included examining the effects of morphological changes by contrast-phase             microscope, the percentage of viable cells, cell cycle distribution mitochondria             membrane potential (ΔΨm), ROS and caspase activities were examined by flow cytometry,             apoptotic cells were examined by DAPI staining and the changes of associated apoptosis             proteins levels were examined by Western blotting. Release of apoptotic factors             from mitochondria was examined by confocal laser microscope. Our results showed             that MMEQ caused morphological changes and inhibited the cell growth of TSGH8301             cells in a time- and dose-dependent manner. MMEQ induced G2/M arrest through the             promotion of chk1, chk2 and cdc25c in TSGH8301 cells. MMEQ caused a marked increase             in the percentage of DNA damage and apoptosis as characterized by DAPI and DNA             fragmentation. The specific inhibitors of caspase-8, -9, and -3 blocked MMEQ-induced             growth inhibition action. A remarkable loss of ΔΨm and increase in ROS production             were observed after a 24-h treatment. MMEQ promoted the levels of caspase-3, caspase-8,             caspase-9, Bax, Bcl-xs, decreased the levels of Bcl-2 and Bid and then led to             dysfunction of ΔΨm, following the releases of cytochrome c, AIF and Endo G from             mitochondria to cytosol and nuclei, and finally caused cell apoptosis. In conclusions,             these molecular mechanisms provide insight into MMEQ-caused growth inhibition,             G2/M arrest and apoptotic cell death in TSGH8301 cells.
Department of Nutrition, China Medical University, Taiwan, Republic of China.
Shu-Chun
SC
Hsu
Chien-Chih
CC
Yu
Jai-Sing
JS
Yang
Kuang-Chi
KC
Lai
Shin-Hwar
SH
Wu
Jen-Jyh
JJ
Lin
Jehn-Hwa
JH
Kuo
Su-Tso
ST
Yang
Ching-Che
CC
Huang
Sheng-Chu
SC
Kuo
Jing-Gung
JG
Chung
D017209:Apoptosis / Q000187:drug effects*; D051033:Apoptosis Inducing Factor / Q000378:metabolism; D052117:Benzodioxoles / Q000494:pharmacology*; D020169:Caspases / Q000378:metabolism*; D059447:Cell Cycle Checkpoints / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D045744:Cell Line, Tumor; D000071877:Checkpoint Kinase 1; D064447:Checkpoint Kinase 2; D045304:Cytochromes c / Q000378:metabolism; D004249:DNA Damage / Q000187:drug effects; D053938:DNA Fragmentation / Q000187:drug effects; D016195:G2 Phase / Q000187:drug effects; D006801:Humans; D053078:Membrane Potential, Mitochondrial / Q000187:drug effects; D008928:Mitochondria / Q000187:drug effects* / Q000378:metabolism; D011494:Protein Kinases / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D015363:Quinolones / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D001749:Urinary Bladder Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology*; D051028:bcl-2-Associated X Protein / Q000378:metabolism; D020687:cdc25 Phosphatases / Q000378:metabolism*
C568352:2-(3-methoxyphenyl)-6, 7-methylenedioxoquinolin-4-one; D051033:Apoptosis Inducing Factor; D052117:Benzodioxoles; D019253:Proto-Oncogene Proteins c-bcl-2; D015363:Quinolones; D017382:Reactive Oxygen Species; D051028:bcl-2-Associated X Protein; D045304:Cytochromes c; D011494:Protein Kinases; D064447:Checkpoint Kinase 2; C000605867:CHEK1 protein, human; C578634:CHEK2 protein, human; D000071877:Checkpoint Kinase 1; D017346:Protein Serine-Threonine Kinases; C517009:CDC25C protein, human; D020687:cdc25 Phosphatases; D020169:Caspases