MMP-9 expression was elevated in 3 of 20 CML-BC patients. Real-time RT-PCR for MMP-9 in samples from healthy subjects (light shaded bar) or patients with CML-BC (dark shaded bar). Expression levels were normalized by GAPDH mRNA. RNA from normal BM cells served as a control (mean of 5 RNA levels of normal BM was defined as 1). MMP-9 mRNA levels exceeded 3.0 in 3 of 20 samples from CML-BC patients.