Tabriz University of Medical Sciences Medical Journal of Tabriz University of Medical Sciences 2783-2031 40 4 2018 10 04 The effects of epigallocatechin gallate on HER-2 gene expression of the human breast adenocarcinoma cells line (SK-BR-3) 67 72 EN Maryam Mokhtari Leila Rouhi Noosha Zia-Jahromi Seyed Hossein Hejazi Journal Article 2018 09 23 Background: One of the most well-known oncogenes in breast cancer is HER2 (ERBB2 or EGFR2). Natural polyphenols are one of the most effective components for inhibiting cancers due to their high efficiency and fewer side effects. Investigators have shown that green tea and its main catechin epigallocatechin-3 gallate (EGCG) may decrease the risk of cancer. In the current study, we investigated the effect of EGCG on HER-2 gene expression of the human breast adenocarcinoma cells line SK-BR-3. Methods: SKBR-3 human breast cancer cells were pretreated with different concentrations of EGCG (200 and 400 µg/mL) for 48 and 72 h. mRNA expression of HER-2 was detected by real time reverse transcriptase polymerase chain reaction (RT-PCR) analysis in the pretreated SKBR-3 cells. Results: EGCG treatment in 48 and 72 h caused a dose-dependent decrease in mRNA expression of HER-2 significantly in group I and group II vs. control group (P<0.05). Conclusion: Epigallocatechin-3 gallate has cytotoxic effect on SKBR3 cells. Our findings suggest that EGCG may be useful in treatment of breast cancer.