title: Effects of Coptis extract combined with chemotherapeutic agents on ROS production, multidrug resistance, and cell growth in A549 human lung cancer cells.
abstract: BACKGROUND
  Non-small cell lung cancer is associated with high expression of multidrug resistance (MDR) proteins and low production of reactive oxygen species (ROS). Coptis extract (COP), a Chinese medicinal herb, and its major constituent, berberine (BER), have anticancer properties. This study aims to investigate the effects of COP and BER combined with chemotherapeutic agents, including fluorouracil (5-FU), camptothecin (CPT), and paclitaxel (TAX), on cell proliferation, ROS production, and MDR in A549 human non-small cell lung cancer cells.
  
  
  METHODS
  A549 cells were treated with different doses of COP and BER, combined with 5-FU, CPT, and TAX. Cell viability was measured by an XTT (2,3-bis-(2-methoxy-4- nitro-5-sulfophenyl)-2 H-tetrazolium-5-carboxanilide) assay. Intracellular ROS levels were determined by measuring the oxidative conversion of cell permeable 2',7'-dichlorofluorescein diacetate to fluorescent dichlorofluorescein. MDR of A549 cells was assessed by rhodamine 123 retention assay.
  
  
  RESULTS
  Both COP and BER significantly inhibited A549 cell growth in a dose-dependent manner. Combinations of COP or BER with chemotherapeutic agents (5-FU, CPT, and TAX) exhibited a stronger inhibitory effect on A549 cell growth. In addition, COP and BER increased ROS production and reduced MDR in A549 cells.
  
  
  CONCLUSIONS
  As potential adjuvants to chemotherapy for non-small cell lung cancer, COP and BER increase ROS production, reduce MDR, and enhance the inhibitory effects of chemotherapeutic agents on A549 cell growth.
authors.affiliation: Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Charlestown, Boston, MA, 02129, USA. kang.jing@mgh.harvard.edu.
authors.forename: Chengwei
authors.initials: C
authors.lastname: He
authors.forename: Rong
authors.initials: R
authors.lastname: Rong
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.forename: Jianbo
authors.initials: J
authors.lastname: Wan
authors.forename: Keyuan
authors.initials: K
authors.lastname: Zhou
authors.forename: Jing X
authors.initials: JX
authors.lastname: Kang