title: Transcriptomic analysis by RNA-seq reveals AP-1 pathway as key regulator that green tea may rely on to inhibit lung tumorigenesis.
abstract: Green tea is a promising chemopreventive agent for lung cancer. Multiple signaling events have been reported, however, the relative importance of these mechanisms in mediating the chemopreventive function of green tea is unclear. In the present study, to examine the involvement of AP-1 in green tea polyphenols induced tumor inhibition, human NSCLC cell line H1299 and mouse SPON 10 cells were identified as AP-1 dependent, as these two lines exhibit high constitutive AP-1 activity, and when TAM67 expression was induced with doxycycline, cell growth was inhibited and correlated with suppressed AP-1 activity. RNA-seq was used to determine the global transcriptional effects of AP-1 inhibition and also uncover the possible involvement of AP-1 in tea polyphenols induced chemoprevention. TAM67 mediated changes in gene expression were identified, and within down-regulated genes, AP-1 was identified as a key transcription regulator. RNA-seq analysis revealed that Polyphenon E-treated cells shared 293 commonly down-regulated genes within TAM67 expressing H1299 cells, and by analysis of limited Chip-seq data, over 10% of the down-regulated genes contain a direct AP-1 binding site, indicating that Polyphenon E elicits chemopreventive activity by regulating AP-1 target genes. Conditional TAM67 expressing transgenic mice and NSCLC cell lines were used to further confirm that the chemopreventive activity of green tea is AP-1 dependent. Polyphenon E lost its chempreventive function both in vitro and in vivo when AP-1 was inhibited, indicating that AP-1 inhibition is a major pathway through which green tea exhibits chemopreventive effects.
authors.affiliation: Department of Surgery, The Alvin J. Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri; Medical College of Wisconsin Cancer Center, Department of Pharmacology and Toxicology, Medical College of Wisconsin, Milwaukee, Wisconsin.
authors.forename: Jing
authors.initials: J
authors.lastname: Pan
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Donghai
authors.initials: D
authors.lastname: Xiong
authors.forename: Peter
authors.initials: P
authors.lastname: Vedell
authors.forename: Ying
authors.initials: Y
authors.lastname: Yan
authors.forename: Hui
authors.initials: H
authors.lastname: Jiang
authors.forename: Peng
authors.initials: P
authors.lastname: Cui
authors.forename: Feng
authors.initials: F
authors.lastname: Ding
authors.forename: Jay W
authors.initials: JW
authors.lastname: Tichelaar
authors.forename: Yian
authors.initials: Y
authors.lastname: Wang
authors.forename: Ronald A
authors.initials: RA
authors.lastname: Lubet
authors.forename: Ming
authors.initials: M
authors.lastname: You
mesh_terms: D000818:Animals; D063646:Carcinogenesis / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D016000:Cluster Analysis; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D053263:Gene Regulatory Networks; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism*; D051379:Mice; D010446:Peptide Fragments / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D016755:Proto-Oncogene Proteins c-jun / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects*; D013662:Tea / Q000737:chemistry*; D018808:Transcription Factor AP-1 / Q000235:genetics / Q000378:metabolism*; D059467:Transcriptome
chemical_list: D010446:Peptide Fragments; D047428:Protein Kinase Inhibitors; D016755:Proto-Oncogene Proteins c-jun; C439528:TAM67 peptide; D013662:Tea; D018808:Transcription Factor AP-1
keywords: AP-1; green tea; lung cancer