Alcoholic extract of Tarantula cubensis (Theranekron®) induce autophagy on gastric cancer cells

Aim: To evaluate the effects of theranekron in respect of autophagy on gastric cancer that is the fifth leading cancer type worldwide. Metods: In the present study, metastatic AGS and non-metastatic MKN-45 human gastric cell lines were used together with HEK-293 non-cancer cells as controls. Cytotoxic effect of theranekron besides appropriate treatment time was investigated through cell proliferation by using Cell Proliferation assay Kit (MTT) using different concentrations of the drug. The autophagic effect of the drug was determined using the LC3-GFP translocation assay and western blot analysis. All experiments were performed also using the ethanol since Tarantula cubensis spider was processed and diluted in 60% alcohol to generate as a drug. Results: MTT assay results demonstrated that the half maximal inhibitory concentration of theranekron was ~100 μM, its effect was found to be significant at 6 hrs, and theranekron decreased the cell viability in all cell lines without specificity in respect to the increasing concentrations. Additionally, a significantly increased GFP accumulation was detected in the autophagosomes of the cells treated with theranekron compared to non treated cells, indicating the presence of autophagy. Conclusion: These findings were confirmed by LC3-I to LC3-II conversion with the western blot analysis. The data of ethanol experiments; however, demonstrated that ethanol also induced a cytotoxic effect and autophagic cell death. Our results suggested that theranekron results in cell death and stimulate autophagy process, but it is not specific for cancer cells since it represented similar results on non-cancer control cells. Moreover, the effect of theranekron on cell death might mostly occur through alcohol in which it is extracted.