FOXP3 and HER-2/ErbB2 in Breast Cancer: Finding Regulatory Links

Abstract

The transmembrane tyrosine kinase receptor, HER2/ErbB2, has been a subject of many studies owing to its
predictive and prognostic values and its being a target of antibody-mediated treatment. Retrospective evidence
strongly proposes that the over expression of HER2 is related to reduced disease free and overall survival in
node positive and perhaps also node negative breast cancers. Prospective attempts showed that antibodies
to HER2 can form tumor responses in advanced breast cancer women which overexpress this molecule.
The existence of forkhead box protein 3 (FOXP3) in cells of breast cancer is a subject of debate. We have
systematically analyzed the FOXP3 expression in 20 breast carcinoma samples at transcript levels. Recent
progresses in understanding breast cancer crosstalk, homing processes, tumor cell dormancy, premetastatic
niche formation and finally recognition of their micromilieu cytokines, growth factors and chemokinesmight
provide the foundation of developing targeted treatment plans potentially rendering primary carcinomas and
their metastases more responsive to chemotherapies. The current review has focused on the deep connections
between HER-2 and FoxP3 in context of considering the determination of both of these molecules together
to rationalize or more personalize the future research directions leading to better treatment for women with
breast carcinoma.