Bcr-Abl tyrosine-kinase inhibitor

Bcr-Abl tyrosine-kinase inhibitor

The Bcr-Abl tyrosine-kinase inhibitor is a type of pharmacological agent that specifically targets and inhibits the Bcr-Abl tyrosine kinase. This enzyme is a fusion protein, the product of the Philadelphia chromosome, a genetic abnormality found in 95% of people with chronic myelogenous leukemia (CML) and in some patients with acute lymphoblastic leukemia (ALL).

Mechanism of Action

The Bcr-Abl tyrosine-kinase inhibitor works by binding to the ATP-binding site of the Bcr-Abl enzyme, thereby preventing its phosphorylation and subsequent activation. This inhibition disrupts the proliferation and survival of leukemic cells, leading to their apoptosis, or programmed cell death.

Types of Bcr-Abl Tyrosine-Kinase Inhibitors

There are several types of Bcr-Abl tyrosine-kinase inhibitors, including Imatinib, Dasatinib, and Nilotinib. These drugs differ in their potency, selectivity, and side effect profiles.

Imatinib

Imatinib, also known as Gleevec, was the first Bcr-Abl tyrosine-kinase inhibitor to be approved by the Food and Drug Administration (FDA). It is used as a first-line treatment for CML and has dramatically improved the prognosis for patients with this disease.

Dasatinib

Dasatinib is a second-generation Bcr-Abl tyrosine-kinase inhibitor. It is more potent than imatinib and can overcome resistance to first-generation inhibitors.

Nilotinib

Nilotinib is another second-generation Bcr-Abl tyrosine-kinase inhibitor. It is similar to dasatinib in its potency and ability to overcome resistance, but it has a different side effect profile.

Side Effects

The side effects of Bcr-Abl tyrosine-kinase inhibitors can include nausea, vomiting, diarrhea, muscle pain, and fluid retention. More serious side effects can include liver toxicity, cardiovascular disease, and bone marrow suppression.

Resistance

Resistance to Bcr-Abl tyrosine-kinase inhibitors can occur due to mutations in the Bcr-Abl gene. This resistance can often be overcome with second-generation inhibitors.

See Also

• Tyrosine kinase
• Tyrosine kinase inhibitor
• Philadelphia chromosome
• Chronic myelogenous leukemia
• Acute lymphoblastic leukemia