Apoptosis of human melanoma cells induced by the novel compounds propolin A and propolin B from Taiwenese propolis.

Abstract

We recently demonstrated that two new prenylflavanones, propolin A and propolin B, isolated and characterized from Taiwanese propolis, induced cytotoxicity effect in human melanoma A2058 cells and shows a strong capability to scavenge free radicals. In this study, propolin A effectively induced a cytotoxic effect on five different cancer cell lines. Similar results were obtained for propolin B. DNA flow cytometric analysis and DNA fragmentation ladder indicated that propolin A and propolin B actively induced apoptosis in A2058 cells. To address the mechanism of the apoptosis effect of propolin A and propolin B, we evaluated the apoptosis-related proteins in A2058 cells. The levels of procaspase-8, Bid, procaspase-3, DFF45, and PARP were decreased in dose- and time course-dependent manners. Furthermore, also found propolin A and propolin B was capable of releasing cytochrome c from mitochondria to cytosol. The findings suggest that propolin A and propolin B may activate a mitochondria-mediated apoptosis pathway. On the other hand, our data show that propolin B inhibitied xanthine oxidase activity more efficiently than propolin A or CAPE. However, CAPE suppressed ROS-induced DNA strand breakage more efficiently than propolin A or propolin B. All these results indicated that propolin A and propolin B may trigger apoptosis of A2058 cells through mitochondria-dependent pathways and also shown that propolin A and propolin B were strong antioxidants.

• Authors: Chia-Nan Chen, Chia-Li Wu, Jen-Kun Lin
• Journal: Cancer letters (Cancer Lett) Vol. 245 Issue 1-2 Pg. 218-31 (Jan 08 2007) ISSN: 0304-3835 [Print] Ireland
• PMID: 16516378 (Publication Type: Journal Article)

Chemical References

• Caffeic Acids
• DNA, Circular
• Flavonoids
• Reactive Oxygen Species
• propolin A
• propolin B
• Cytochromes c
• Propolis
• Xanthine Oxidase
• Caspase 3
• Caspase 8
• caffeic acid phenethyl ester
• Phenylethyl Alcohol

Topics

• Apoptosis (drug effects)
• Blotting, Western
• Caffeic Acids (pharmacology)
• Caspase 3 (metabolism)
• Caspase 8 (metabolism)
• Cell Cycle (drug effects)
• Cell Line, Tumor
• Cell Survival (drug effects)
• Cytochromes c (metabolism)
• DNA Breaks
• DNA Fragmentation (drug effects)
• DNA, Circular (drug effects)
• Dose-Response Relationship, Drug
• Flavonoids (chemistry, isolation & purification, pharmacology)
• Flow Cytometry
• HL-60 Cells
• Humans
• Melanoma (genetics, metabolism, pathology)
• Mitochondria (drug effects, metabolism)
• Molecular Structure
• Phenylethyl Alcohol (analogs & derivatives, pharmacology)
• Propolis (chemistry)
• Reactive Oxygen Species (antagonists & inhibitors, metabolism)
• Signal Transduction (drug effects)
• Xanthine Oxidase (metabolism)