Induction of apoptosis by DC-81-indole conjugate agent through NF-kappaB and JNK/AP-1 pathway.
DC-81, an antitumor antibiotic produced by Streptomyces species, belongs to the pyrrolo[2,1- c][1,4]benzodiazepine (PBD) family, which are potent inhibitors of nucleic acid synthesis. We previously reported an efficient synthesis of PBD hybrids linked with indole carboxylates. Recently, we have also shown that a PBD hybrid (IN6CPBD) agent can activate the apoptotic pathway mediated by mitochondria. In this study, we will examine the transcription factors nuclear factor-kappaB (NF-kappaB) and activator protein-1 (AP-1) that functionally regulate cell proliferation, transformation, and apoptosis. To investigate the IN6CPBD-induced alterations in NF-kappaB and AP-1 activity that involve cell cycle regulation, we exposed human melanoma A375 cells to different concentrations of IN6CPBD. Our data revealed that treatment of A375 cells with IN6CPBD resulted in a marked loss of cells from the G2/M phase of the cell cycle and an increase in Ca (2+) and cAMP and promoted phosphorylation of Jun N-terminal kinase (JNK) expression. By using the luciferase reporter assay, the NF-kappaB activities were decreased; however, AP-1 activity was further enhanced after A375 cells were treated with graded concentrations of IN6CPBD. Blockade of NF-kappaB or JNK activity further enhanced caspase-3 substrate PARP cleavage and subsequent apoptotic cell death.
Faculty of Biotechnology, College of Life Science, Department of Dermatology, Kaohsiung Medical University, Kaohsiung, Taiwan.
Wan-Ping
WP
Hu
Feng-Yuan
FY
Tsai
Hsin-Su
HS
Yu
Ping-Jyun
PJ
Sung
Long-Sen
LS
Chang
Jeh-Jeng
JJ
Wang
D017209:Apoptosis / Q000187:drug effects*; D001381:Azepines / Q000494:pharmacology*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D048670:MAP Kinase Kinase 4 / Q000378:metabolism*; D008545:Melanoma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology; D016328:NF-kappa B / Q000378:metabolism*; D018808:Transcription Factor AP-1 / Q000378:metabolism*
D001381:Azepines; C523952:IN6CPBD; D007211:Indoles; D016328:NF-kappa B; D018808:Transcription Factor AP-1; D048670:MAP Kinase Kinase 4