One of the most intriguing MMPs, MMP-8, also known as collagenase-2 or neutrophil collagenase, was long thought to be expressed solely in neutrophil precursors since it has been cloned from RNA extracted from peripheral blood leukocytes of a patient with chronic granulocytic leukemia [14]. Here, MMP8 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.