Abstract:

Objectives: Tannic acid (TA), a plant polyphenol, is known to have anti-carcinogenic, anti-oxidant, anti-mutagenic, anti-microbial, anti-allergic, anti-inflammatory activities. However, a precise mechanism responsible for the anti-cancer activity of TA in breast cancer has not yet been clearly described. The aim of this study was to investigate the effect of TA on the pro-apoptotic Bax protein in a human breast cancer cell line (MCF-7). Materials and methods: In this study, TA in various concentrations (0, 25, 50 and 100 μM) were administrated at various time points (24th h, 48th h and 72nd h) to breast cancer cells (MCF-7). The percentages of pro-apoptotic Bax protein in these cells were determined by immunohistochemical staining. Results: At the completion of the study, percentages of the pro-apoptotic Bax protein in pro-apoptotic cancer cells were found to be increased in a time-dependent manner after exposure to various concentrations of TA. This increase was at highest level with the concentration of 25 μM at 72nd hour. Conclusion: Based on our results, we suggested that TA could induce apoptosis of breast cancer cells by increasing Bax protein. Further studies evaluating the relationship of TA with other proteins that have a role in apoptotic pathways are warranted to support the findings of this study.

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