title: Apoptogenic effect of 7,8-diacetoxy-4-methylcoumarin and 7,8-diacetoxy-4-methylthiocoumarin in human lung adenocarcinoma cell line: role of NF-kappaB, Akt, ROS and MAP kinase pathway.
abstract: Coumarin (1,2-benzopyrone) is a naturally occurring fragrant compound found in a variety of plants and spices. Coumarins have attracted intense interest in recent years because of their diverse pharmacological activities. This study examines the antioxidant coumarin 7,8-diacetoxy-4-methylcoumarin (DAMC) and its thiocoumarin derivative 7,8-diacetoxy-4-methylthiocoumarin (DAMTC) for their effect on human non-small cell lung cancer A549 cells. Here we show that both DAMC and DAMTC not only inhibited cell proliferation, but also induced apoptosis with an IC(50) of 160 microg/ml as confirmed by morphological examination, annexin-V assay and flow cytometric analysis. Interestingly, it was observed that these two coumarin compounds exhibited little cytotoxicity towards peripheral blood mononuclear cells but induced apoptosis in malignant cells. DAMC/DAMTC treatment also resulted in pronounced release of apoptogenic cytochrome c from mitochondria to cytosol, alteration of mitochondrial membrane potential (DeltaPsi(m)), and activation of caspase-9 and caspase-3. Although an increase in the levels of reactive oxygen species (ROS) was observed, pre-treatment with antioxidant showed no protective effect against DAMC/DAMTC-induced apoptosis. Results of present study suggest that downregulation of Bcl-xl, Cox-2 and mitogen activated protein kinase pathway and upregulation of p53, Akt and NF-kappaB pathway are involved in the underlying molecular mechanism of apoptosis induction by DAMC and DAMTC in A549 cells.
authors.affiliation: Molecular Immunogenetics Laboratory, Institute of Genomics and Integrative Biology, Mall Road, Delhi 110007, India.
authors.forename: Anita
authors.initials: A
authors.lastname: Goel
authors.forename: Ashok K
authors.initials: AK
authors.lastname: Prasad
authors.forename: Virinder S
authors.initials: VS
authors.lastname: Parmar
authors.forename: Balaram
authors.initials: B
authors.lastname: Ghosh
authors.forename: Neeru
authors.initials: N
authors.lastname: Saini
mesh_terms: D000230:Adenocarcinoma / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D017209:Apoptosis / Q000187:drug effects*; D020169:Caspases / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects; D003374:Coumarins / Q000494:pharmacology*; D045304:Cytochromes c / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004354:Drug Screening Assays, Antitumor; D006801:Humans; D008175:Lung Neoplasms / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D008928:Mitochondria / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism*; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism*; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D014407:Tumor Cells, Cultured
chemical_list: C114369:7,8-diacetoxy-4-methylcoumarin; C540361:7,8-diacetoxy-4-methylthiocoumarin; D003374:Coumarins; D016328:NF-kappa B; D017382:Reactive Oxygen Species; D045304:Cytochromes c; D051057:Proto-Oncogene Proteins c-akt; D020928:Mitogen-Activated Protein Kinases; D020169:Caspases