Breast cancer is the most common type of cancer and a leading cause of cancer mortality among women. berberine is an isoquinoline alkaloid isolated from medicinal plants such as berberis aristata and coptis chinensis. in recent years, berberine has been shown anticancer activitiy in different cancer cell lines. theophylline is a methylxantine drug that is used to treat airway diseases for more 60 years.
Methods
In this study the effect of berberine alone and in combination with theophylline on cell viability was investigated by mtt. also annexin v flow cytometric analysis and western blot analysis of parp cleavage were used to evaluate apoptosis.
Results
mtt assay showed that berberine treatment inhibited cell survival in a dose dependent manner and ic50 was 100 µm, whereas theophylline in combination with berberine decreased ic50 to 50 µm. the control and treated cells were stained with annexin v/pi, and detected with fac scan flow cytometer. the results showed that the percentage of necrotic cells increased upon increasing berberine concentration. when the cells pretreated with theophylline and then exposed to berberine, the percentage of apoptotic cells increased but the percentage of necrosis in the cells was negligible. parp cleavage was investigated by specific antibody for 89 kda fragment. the results revealed that cleaved parp increased significantly when the cells pretreated with theophylline compared to berberine treatment alone.
Conclusion
From the results it is concluded that theophylline increases toxicity of berberine and reduces necrosis induced by berberine, suggesting that combination of berberine with theophylline may be an effective chemotherapeutic agent against breast cancer cells.
Keywords
Berberine, theophylline, mda-mb-231 breast cancer cells, apoptosis
