STAT5A and neoplasm: Because tyrosine phosphorylation causes the dimerization of STATs and their translocation to the nucleus, where they bind to DNA and regulate gene transcription [36], and also of CREB related transcription factor which binds CRE and heterodimerizes with CREB in nucleus [32], we determined whether ART suppresses the DNA binding activities of both STAT5 and CREB in tumor cells.