Scientific Journal of

Abstract
Background and Objectives
Arsenic trioxide has anti-cancer effects on a wide range of cancers, mainly by inducing apoptosis in cancerous cells. Thalidomide is an inhibitor of angiogenesis. The main purpose of this study was to investigate the combined effect of arsenic trioxide and thalidomide on the expression level of VEGF A gene.
 
Materials and Methods
In this experimental study, MTT test was used to investigate the effect of arsenic trioxide and thalidomide both in isolation as combined on cell viability of KG-1 and U937 cells at different times and different doses. Cell apoptosis was assessed by flow cytometry. The level of mRNA expression of VEGF A gene was assessed by Real Time PCR. Student-t, ANOVA and SPSS-17 software were used for data analysis.
 
Results
The selective doses of arsenic trioxide in the KG-1 and U937 cell lines were 1.618 μM and 1 μM, respectively. The selective doses of thalidomide in the KG-1 and U937 cell lines were 80 μM and 60 μM, respectively. Combination of arsenic trioxide and thalidomide had a significant effect on both cell lines. On the other hand, the expression of the VEGF A gene significantly decreased.
 
Conclusions  
The present study showed that the expression of VEGF A gene in 1-KG and U937 cell lines decreased and the combination effect of arsenic trioxide and thalidomide on the cells induced apoptosis. To confirm these results further investigation is required on the protein level.