How does GLIVEC work?
CML is associated with a particular type of abnormal chromosome called the Philadelphia chromosome. The Philadelphia chromosome contains a faulty gene (called BCR-ABL), which produces an abnormal version of a protein, an enzyme called tyrosine kinase. Under normal circumstances, the tyrosine kinase protein helps to convey signals between cells to control their growth and division. However in CML, because the tyrosine kinase is defective, the signals are not controlled in any way and the white blood cells divide continuously with massive numbers of cells being produced. Glivec is a small molecule which works by targeting the faulty tyrosine kinase enzyme and sticking to it, which prevents it from stimulating the cells to grow. This is why Glivec is known as a ‘tyrosine kinase inhibitor’ Glivec is also known as a ‘signal transduction inhibitor’ because it blocks the ‘grow’ signal.
