For instance, CML cell lines ectopically expressing an eIF2α Ser51 → Ala mutant (blocking phosphorylation at this site and eIF2α activation) had reduced expression and secretion of matrix metalloproteinases (MMPs), enzymes which are involved in the degradation of extracellular matrix components [44]. The gene discussed is EIF2A; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.