Paradoxically, STAT4 is negatively related to GATA3 expression in breast cancer, probably because of the tissue specific role of GATA3. Actually, we noticed that lots of GATA3-related genes in B-ALL lost their association with GATA3 expression in breast cancer, or even exhibit the opposite association directions (e.g., STAT4), providing the possible explanation of the opposite role of GATA3 in different cancer types (e.g., potential tumor suppressor in breast cancer but oncogene in leukemia). The gene discussed is STAT4; the disease is leukemia.