The Synergic Cytotoxicity Effect of Cisplatin and Salicylic Acid on the A2780 cp Ovarian Carcinoma Cell Line, and the Evaluation of p21 and ZEB1 Expression Levels

Ovarian cancer is regarded as the most lethal gynecologic disease worldwide. The aims of the present study were to investigate the synergic cytotoxicity effects of cisplatin and salicylic acid on cell viability, the evaluation of cellular death type in A2780cp cell line and also the assessment of p21 and ZEB1 expression levels. In RPMI medium, A2780cp cells were proliferated at different concentrations of the two drugs. The growth inhibitory effect of the drugs on cancer cells were evaluated employing a rapid colorimetric test, MTT assay. For determining the rate of apoptosis, the amounts of Annexin V and PI were assessed using flow cytometry. The expression of two genes were measured by real-time PCR. The results of MTT assay indicated that 45.73 ± 0.372% of residual tumor cells were still viable in 4 μg/mL and 0.02 mM concentrations of both cisplatin and salicylic acid after 48h therapies, respectively. In addition, the results of flow cytometry also demonstrated that the viability rate was different from 79.9 ± 2.591% in a control sample to 22.4 ± 2.08% in a sample treated with the combined concentrations of two drugs. Salicylic acid contributed to amplifying the antitumor effects of cisplatin by inducing apoptosis. The expression level of p21 as well as ZEB1 was declined under the synergic effects of two drugs. The reason is related to the dual role of p21 as an oncogene and tumor suppressor. Therefore, downregulation of these two genes significantly declined cancer cell viability in response to the combined drugs.