Fattah FSA, et al. - Expression of GATA3 in breast cancer (BC) cell lines and clinical specimens from BC patients was investigated in Taiwan. To determine the mRNA level of GATA3 from 241 pairs of matched tumor and adjacent normal tissues from anonymous female donors, semi-quantitative reverse transcriptase (RT)-polymerase chain reaction (PCR), quantitative real-time PCR was carried out. A correlation was found between GATA3 expression and only estrogen receptor-positive (ER+). The data presented in this work showed a higher GATA3 expression was a good prognostic factor for overall survival (OS) for ER+/ BC patients.