Author(s)

Zhi-Peng Liu, Xue-Gang Luo, Shu Guo, Jian-Xin Wang, Xin Zhang, Nan Wang, Yong Jiang, Tong-Cun Zhang

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Myocardin-related transcription factors A (MRTF-A) is a myocardin-related transcription factor that have been found strongly activated CarG box–containing genes through its direct binding to serum response factor (SRF). In the present study, the MRTF-A ex-pression vector was constructed. The MTT assay showed that transfection of MRTF-A could significantly decrease the anti-tumor effect of tamoxifen on MCF-7 breast cancer cells. The bioinformatics analysis found that the CarG element existed in the pro-moter region of COMT gene of many familiar verte-brates, including of human, rhesus macaque, chimpanzee, etc. The results of RT-PCR assay further showed that MRTF-A could enhance the transcrip-tion level of COMT. These results are the first to indicate that COMT might be a target gene which could be regulated by MRTF-A/SRF, and such transactivation event might be involved in the process of tamoxifen resistance.

MRTF-A; Tamoxifen; COMT; Breast Cancer

Liu, Z. , Luo, X. , Guo, S. , Wang, J. , Zhang, X. , Wang, N. , Jiang, Y. and Zhang, T. (2009) MRTF-A transactivates COMT gene and decreases the anti-tumor effects of tamoxifen. Journal of Biomedical Science and Engineering, 2, 559-563. doi: 10.4236/jbise.2009.27081.