A novel bis-benzylidenecyclopentanone derivative, BPR0Y007, inducing a rapid caspase activation involving upregulation of Fas (CD95/APO-1) and wild-type p53 in human oral epidermoid carcinoma cells.
BPR0Y007, a bis-benzylidenecyclopentanone derivative (2,5-bis- (4-hydroxy-3-methoxybenzylidene) cyclopentanone), was identified in our laboratory as a novel antineoplastic agent with a broad spectrum of antitumor activity against many human cancer cells. A previous study showed that BPR0Y007 inhibited DNA topoisomerase I (Top 1) activity and prevented tubulin polymerization. Notably, no cross-resistance with BPR0Y007 was observed in camptothecin-, VP-16- or vincristine-resistant cell lines. In this study, we further investigated the cellular and molecular events underlying the antitumoral function of this compound in human oral epidermoid carcinoma KB cells, focusing on the early cytotoxic effect. Treatment of KB cells with BPR0Y007-induced G(2)/M phase arrest followed by sub-G(1) phase accumulation. Annexin-V-propidium iodide (PI) binding assay and DNA fragmentation assay further indicated that BPR0Y007-induced cell death proceeded through an apoptotic pathway as opposed to via necrosis. This compound produced a time-dependent activation of caspases-3 and -8, however, another caspase-3 initiator, caspase-9, was only marginally activated at later time point. We further demonstrated that the activation of the caspases cascade and nuclear fragmentation was not associated with inactivated Bcl-2 and perturbed mitochondrial membrane potential by BPR0Y007. The finding that BPR0Y007-induced apoptosis through a membrane-mediated mechanism was supported by up-regulated expression of Fas (CD95/APO-1), but not Fas-L. Furthermore, up-regulation of p53 and its affected gene, MDM2, in KB cells was found after BPR0Y007 exposure. Overall, our results demonstrated that the BPR0Y007 could induce an early cytotoxic apoptosis through a caspase-8-dependent but mitochondrial-caspase-9 independent pathway, and involving upregulation of p53.
Juang
Shin-Hun
SH
Cancer Cooperative Ward in National Taiwan University Hospital, Division of Cancer Research, National Health Research Institutes, 7, Chung-Shan Road, Taipei, Taiwan, ROC.
Pan
Wen-Yu
WY
Kuo
Ching-Chuan
CC
Liou
Jing-Ping
JP
Hung
Yi-Mei
YM
Chen
Li-Tzong
LT
Hsieh
Hsing-Pang
HP
Chang
Jang-Yang
JY
D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D001597:Benzylidene Compounds / Q000494:pharmacology*; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation / Q000187:drug effects; D053222:Fas Ligand Protein; D016195:G2 Phase / Q000187:drug effects; D006801:Humans; D007624:KB Cells; D008562:Membrane Glycoproteins / Q000378:metabolism; D008928:Mitochondria / Q000187:drug effects / Q000502:physiology; D008938:Mitosis / Q000187:drug effects; D010422:Pentanones / Q000494:pharmacology*; D011506:Proteins / Q000378:metabolism; D013997:Time Factors; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism*; D015854:Up-Regulation / Q000187:drug effects; D019014:fas Receptor / Q000378:metabolism*
C488183:2,5-bis(4-hydroxy-3-methoxybenzylidene)cyclopentanone; D000970:Antineoplastic Agents; D001597:Benzylidene Compounds; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D008562:Membrane Glycoproteins; D010422:Pentanones; D011506:Proteins; D016159:Tumor Suppressor Protein p53; D019014:fas Receptor; C505407:CASP3 protein, human; C505530:CASP8 protein, human; C506433:CASP9 protein, human; D053148:Caspase 3; D053181:Caspase 8; D053453:Caspase 9; D020169:Caspases