title: Anti-Proliferative and Apoptosis-Inducing Effect of Theabrownin against Non-small Cell Lung Adenocarcinoma A549 Cells.
abstract: With the highest cancer incidence rate, lung cancer, especially non-small cell lung cancer (NSCLC), is the leading cause of cancer death in the world. Tea (leaves ofCamellia sinensis) has been widely used as a traditional beverage beneficial to human health, including anti-NSCLC activity. Theabrownin (TB) is one major kind of tea pigment responsible for the beneficial effects of tea liquor. However, its effect on NSCLC is unknown. The aim of the present study was to evaluate anti-proliferative and apoptosis-inducing effect of TB on NSCLC (A549) cells, using MTT assay, morphological observation (DAPI staining),in situterminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, and annexin-V/PI flow cytometry. Subsequently, the expression of several genes associated with cell proliferation and apoptosis were detected by real time PCR assay to explore its potential underlying mechanism. TB was revealed to inhibit cell proliferation of A549 cells in a concentration-dependent and time-dependent manner. Morphological observation, TUNEL assay and flow cytometric analysis evidenced an apoptosis-inducing effect of TB on A549 cells in a concentration-dependent manner. The real time PCR assay demonstrated that TB down-regulated the expression ofTOPO I, TOPO II, andBCL-2, and up-regulated the expression ofE2F1, P53, GADD45, BAX, BIM, andCASP 3,7,8,9, which suggests an activation of P53-mediated apoptotic (caspase-dependent) pathway in response to TB treatment. The western blot analysis showed a similar trend for the corresponding protein expression (P53, Bax, Bcl-2, caspase 3,9, and PARP) and further revealed DNA damage as a trigger of the apoptosis (phosphorylation of histone H2A.X). Accordingly, TB can be speculated as a DNA damage inducer and topoisomerase (Topo I and Topo II) inhibitor that can up-regulateP53expression and subsequently modulate the expression of the downstream genes to induce cell proliferation inhibition and apoptosis of A549 cells. Our results indicate that TB exhibits its anti-NSCLC activity via a P53-dependent mechanism, which may be a promising candidate of natural product for anti-cancer drug development in the treatment of NSCLC.
authors.affiliation: Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd. Hangzhou, China.
authors.forename: Feifei
authors.initials: F
authors.lastname: Wu
authors.affiliation: Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical University Hangzhou, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical University Hangzhou, China.
authors.forename: Wangdong
authors.initials: W
authors.lastname: Jin
authors.affiliation: Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical University Hangzhou, China.
authors.forename: Weiji
authors.initials: W
authors.lastname: Yang
authors.affiliation: Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical University Hangzhou, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical University Hangzhou, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Yan
authors.affiliation: Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd. Hangzhou, China.
authors.forename: Wenlin
authors.initials: W
authors.lastname: Du
authors.affiliation: Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd. Hangzhou, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: School of Medicine, Zhejiang University Hangzhou, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Institute for Cell-Based Drug Development of Zhejiang Province, S-Evans Biosciences, Ltd. Hangzhou, China.
authors.forename: Yonghua
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Theabio Co., Ltd Hangzhou, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Institute of Orthopaedics and Traumatology, Zhejiang Chinese Medical University Hangzhou, China.
authors.forename: Letian
authors.initials: L
authors.lastname: Shan
authors.affiliation: Department of Pharmaceutical Biology, Institute of Pharmacy and Biochemistry, Johannes Gutenberg University Mainz, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Efferth
keywords: A549 cells; P53; apoptosis; lung cancer; theabrownin