ABSTRACT
BACKGROUND: The Lonicera japonica has been used as natural and healthy drink for its anti-inflammatory effect and pleasant odor in China and Taiwan. METHODS: 2D electrophoresis was used to analyze the proteins involved in photoactivated Lonicera japonica-induced CH27 cell apoptosis. The fluorescent dyes MitoTracker Red CMXRos, calcein AM and JC-1 were used to elucidate mitochondrial function. The protein expression was performed by Western blotting. Fluorescent image of endoplasmic reticulum was accomplished by using ER-Tracker Green. This study used fluorescent dye CM-H2DCFDA to detect intracellular generation of reactive oxygen species. RESULTS: The identified proteins can be classified into three major groups, which include proteins involved in mitochondrial function, cytoskeleton-related proteins and proteins associated with endoplasmic reticulum (ER) stress. Photoactivated Lonicera japonica caused a significant effect on the mitochondrial function and ER stress in CH27 cells. The reactive oxygen species producing was found to be involved in photoactivated Lonicera japonica-induced CH27 cell apoptosis. CONCLUSION: Mitochondria and endoplasmic reticulum are the integral targets in photoactivated Lonicera japonica-induced CH27 cell apoptosis. We also demonstrated that ethyl acetate fraction of Lonicera japonica extracts caused photocytotoxicity in a dose-dependent manner in CH27 cells. This could explain the fact that the ethyl acetate fraction of Lonicera japonica extracts may contain compounds which exhibit the photosensitizing activity in CH27 cells.
Subject(s)
Antineoplastic Agents/pharmacology , Lonicera/chemistry , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Plant Extracts/pharmacology , Proteome/drug effects , Antineoplastic Agents/chemistry , Cell Line, Tumor , Cell Survival/drug effects , Endoplasmic Reticulum Stress/drug effects , Humans , Lung Neoplasms/chemistry , Mitochondria/drug effects , Molecular Chaperones/metabolism , Oxidative Stress/drug effects , Photochemical Processes , Plant Extracts/chemistry , Proteomics , Reactive Oxygen Species/metabolismABSTRACT
Microtubules are a proven target for anticancer drug development because they are critical for mitotic spindle formation and the separation of chromosomes at mitosis. 2-(Naphthalene-1-yl)-6-pyrrolidinyl-4-quinazolinone (HL66) induced cell death with the large cells and multiple micronuclei in M21 skin cancer cells. We demonstrated that HL66-induced cell death is caspase-independent and accompanied by the failure of cell cycle progression. Therefore, HL66-induced cell death may be a mitotic catastrophe. HL66 inhibits the dephosphorylation on Thr14 or Tyr15 of cyclin-dependent kinase (Cdk) 1 and the formation of Cdk1/cyclin B1 complex, which might be associated with cell cycle arrest at the S and G(2)/M phases. HL66 is an antimicrotubule agent by molecular modeling on the basis of ligand binding to tubulin molecule. Furthermore, we also demonstrated that HL66, like vinblastine, is a tubulin-destabilizing agent via microtubule disruption in M21 cells. These results describe a novel pharmacological property of HL66 as a microtubule inhibitor, which may make it an attractive new agent for the treatment of skin cancer.