The effect of melittin on the inhibition of Rac1 expression in HeLa cervical cancer cell lines

Background: Cell migration plays a principal role in many biological and pathological processes, including embryonic and tumor metastasis. It is well-known that Rac1 from Rho GTPase family is the key regulator of the cell migration. Melittin is a natural peptide in bee venom with apoptotic and anti cancer effects. This study aimed to examine the effect of melittin on Rac1 expression. Materials and Methods: HeLa cells were cultured in Dulbecco's modified Eagle's medium until they reached 80 confluency, then treated with melittin (0.5 and 1 μg/ml) with the consideration of IC50=1 μg/ml for 6 hours. In the control group the same volume of distilled water, as the melittin solvent, was added. Thereafter, cells were lyzed with buffer and after centrifugation the protein concentration of supernatant was measured using the Bradford method. The amount of Rac1 expression was determined using the Western blotting technique and chemiluminescence. Outcomes were normalized with β-Actin as an internal control and the results were displayed as the percentage against the control. Results: The Rac1expression compared to the control (100), in the presence of different concentrations of melittin (0.5 and 1 μg/ml) were 13.88±1.15 and 1.7±0.96, respectively which showed a significant reduction in Rac1 melittin expression (

The Effect of Melittin on Rac1 Protein Expression as a Metastatic Factor in AGS Gastric Cancer Cell Lines

Introduction: Understanding the molecular mechanisms of metastasis is important for the design and effective use of novel therapeutic strategies in order to combat metastases. One class of molecules that has been implicated in metastasis is Rac1. Regarding complications of conventional therapies such as chemotherapy, current studies are evaluating natural compounds with anticancer Properties. Melittin is a natural compound derived from honey bee venom which has revealed amphipatic properties. Some studies have shown that melittin has an important role in reducing cancer cells metastasis by affecting Rac1 expression. Since the studies on melittin role in regard to Rac1 in gastric cancer cells are rare, the present study examined the effect of melittin on Rac1 protein expression in AGS gastric cancer cells. Methods: AGS cells, after growth and reaching to 80% density, were exposed to 0.2, 0.3, 0.4 μg/ml concentrations of melittin (test groups) for six hours. Then cells were collected, lysed with lysis buffer and Rac1 protein was identified by Western blotting technique. Data were normalized with the β-Actin internal control and calculated as the relative percentage. The study data were analyzed using SPSS statistical software via One-Way Anova test. Results: Comparison of Rac1 expression levels in AGS cancer cells showed that cells which were exposed to 6 hours of 0.2μg/ml (109±5.5), 0.3(105±3.6) melittin had higher Rac1 expression percentages compared to the control (100) and 0.4 (100±2). Rac1 expression percentages were not significant with a confidence interval (CI) of 95% ( P>0.05 ). Conclusion: In this study the results demonstrated that melittin does not have any effect on Rac1 in gastric cancer cells (AGS)