It is a transcription activating factor of zinc finger-rich glutamine that regulates the expression of target genes involved in transcription regulatory factors, contains the structure of the zinc finger in the carboxyl end and especially combines the GC box in DNA promoter (Pearson et al., 2008).The overexpression of EGR1 (zif268, zinc fingers) was able to activate a construct containing tandem of the MDR1 promoter at SP1 sites and increased its expression in human acute and chronic leukemias (McCoy et al., 1995). This evidence concerns the gene SP1 and chronic leukemia.