BACKGROUND AND OBJECTIVE: Gastric cancer is the second most prevalent carcinogenic disease and surgery, chemotherapy and radiation are its principal treatment modalities. However, in most cases, poor response to treatment and adverse side effects are observed regarding these modalities. Given the lack of response to treatment and growing rates of gastric cancer, researchers are trying to come up with more efficient treatments with fewer side effects. In the traditional medicine, licorice has been suggested as a cancer treatment considering its high antioxidant properties and few side effects. This study aimed to evaluate the effect of licorice extract on gastric cancer cell lines.

METHODS: In this experimental study, adenocarcinoma gastric cell lines were prepared from cell bank and were cultured. After passage, the cells were transferred into a 96-well plate. In each well, approximately 2,000 cells in RPMI-1640 culture medium with FBS (10%) were placed. The cells were repeatedly exposed to different concentrations of Glycyrrhetinic acid (0, 1, 10 and100.1 &muM) and Glycyrrhizic acid (10, 1, 100 and 0.1 &muM) for 24 and 48 hours. Finally, the obtained results of the experimental and control groups were compared with each other.

FINDINGS: According to our results, the toxic effect of Glycyrrhetinic and Glycyrrhizic acids is dose and time dependent. In 24 hours, the mean optical density (MOD) in 100 &muM concentration of Glycyrrhetinic acid was 0.41±0.02 and 0.79±0.04 in the experimental and control groups, respectively (p=0.0002). After 48 hours, MOD was 0.16±0.004 and 1.749±0.24 in the experimental and control groups, respectively (p=0.0003). Moreover, the MOD of 100 &muM concentration of Glycyrrhizic acid was 0.78±0.53 and 2.09±0.49 in the experimental and control groups in 48 hours. There was a significant difference between the experimental and control groups (p=0.035).

CONCLUSION: The results of this study demonstrated that the licorice compounds have a toxic effect on carcinogenic cells. Therefore, it is recommended to perform more study on both Glycyrrhizic and Glycyrrhizic acids as effective compounds on gastric cancer treatment.