| Nilotinib
is a selective Bcr/Abl tyrosine kinase inhibitor. This type of
medicine is used in treatment of leukemia (specifically chronic
myeloid leukemia.) Nilotinib is considered a "second-generation"
Bcr/Abl tyrosine kinase inhibitor, building on the success of
imatinib. Because many patients develop resistance to imatinib,
there is excitement about nilotinib. A recent research
report concluded it has "great potential" for leukemia
treatment.
Nilotinib is an analog of imatinib with similar multiple kinase
targets, but without inhibition of the Src gene. (This gene regulates
tyrosine kinase proteins that in turn affect whether cells multiply
or die.) Tyrosine kinase inhibitors interfere with cell communication
and growth. They have been of great interest to scientists in
recent years who hope to use them as an option to treat cancer.
The "binding mode" of nilotinib is energetically more
favorable than that of imatinib. This results in a more selective
targeting of the malignancy. Nilotinib has been shown to have
an approximately 20-fold increased potency in kinase and proliferation
assays compared to imatinib. This is especially important for
older patients and they tend to have trouble tolerating imatinib
treatment. The higher dosages required for imatinib make it tough;
nilotinib is hoped to alleviate the side
effects but still be effective.
Researchers have been interested in aurora kinases as targets
for cancer therapy and seveal drugs are in development. Oncogenic
BCR-ABL tyrosine kinase, which is deregulated in as many as 95%
of chronic myeloid leukemia (CML) patients and in ~20% of adult
Philadelphia-positive (Ph+) acute lymphoblastic leukemia (ALL)
patients. ABL kinase domain mutations have been implicated in
the resistance to imatinib mesylate of Philadelphia-positive (Ph+)
leukemia patients.
Mast cells in tumors are affected by the new class of anti-cancer
agents called kinase inhibitors, which includes nilotinib. Inside
the body, mast cells regulate t-cells, promote blood clots, and
enable the growth of blood vessels. The kinase inhibitors are
considered a form or "targeted cancer therapy" because
they are selective in the type of cells they affect. |