GATA-3 Expression as a Predictor of Hormone Response in Breast Cancer

• Published in: Journal of the American College of Surgeons Vol. 200; no. 5; pp. 705 - 710
• Main Authors: Parikh, Purvi, Palazzo, Juan P., Rose, Lewis J., Daskalakis, Constantine, Weigel, Ronald J.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.05.2005; Elsevier Science
• Subjects: Adult; Aged; Antineoplastic Agents, Hormonal - therapeutic use; Biological and medical sciences; Breast Neoplasms - drug therapy; Breast Neoplasms - metabolism; Case-Control Studies; Female; GATA3 Transcription Factor; General aspects; Humans; Immunohistochemistry; Logistic Models; Medical sciences; Middle Aged; Pilot Projects; Predictive Value of Tests; Staining and Labeling; Transcription Factors - metabolism; Transcription factor GATA3; Hormone; Medicine; Mammary gland diseases; Surgery; Prediction; Breast cancer; Mammary gland; Malignant tumor; Predictive factor
• ISSN: 1072-7515; 1879-1190
• DOI: 10.1016/j.jamcollsurg.2004.12.025

Expression of estrogen receptor-α (ERα) as determined by immunohistochemistry of tumor tissue is currently the most clinically useful test to predict hormone responsiveness of breast cancer. Thirty percent of ERα-positive breast cancers do not respond to hormonal therapy. GATA-3 is a transcription factor that is expressed in association with ERα and there is evidence that GATA factors influence response to estrogen. In this pilot study, we investigated whether GATA-3 expression is associated with hormone response in breast cancer. Breast cancer tissue was stained for GATA-3 expression by immunohistochemistry in ERα-positive cancers from 28 patients, 14 of whom were defined as hormone unresponsive (cases) and 14 of whom were age-matched controls with hormone-responsive, ERα-positive cancers (controls). Comparing cases and controls, there were no differences in expression of ERα; progesterone receptor, ErbB2; or tumor grade. Using 20% nuclear staining to characterize tumors as GATA-3 positive or GATA-3 negative, 6 of 14 (43%) cancers in the hormone-unresponsive group and none of the controls were classified as GATA-3 negative (odds ratio, 8.2; 95% confidence interval, 1.2−∞; p = 0.031). Using different cut points to characterize GATA-3 positivity yielded very similar results, indicating a positive association between lack of GATA-3 expression and lack of response to hormonal therapy. The study suggests that analyzing ERα-positive breast tumors for GATA-3 using immunohistochemistry might improve prediction of hormone responsiveness. The association between GATA-3 expression and hormone response suggests that GATA-3 may play a role in mechanisms controlling response to estrogen.