Tyrosine Kinase - Clinical Significance

Clinical Significance

Tyrosine kinases are particularly important today because of their implications in the treatment of cancer. A mutation that causes certain tyrosine kinases to be constitutively active has been associated with several cancers. Imatinib (brand names Gleevec and Glivec) is a drug able to bind the catalytic cleft of these tyrosine kinases, inhibiting its activity.

Tyrosine kinase activity is also significantly involved in other events that are sometimes considered highly unfavorable. For instance, enhanced activity of the enzyme has been implicated in the derangement of the function of certain systems, such as cell division. Also included are numerous diseases related to local inflammation such as atherosclerosis and psoriasis, or systemic inflammation such as sepsis and septic shock. A number of viruses target tyrosine kinase function during infection. The polyoma virus affects tyrosine kinase activity inside the nuclear matrix. Fibroblasts are cells involved in wound healing and cell structure formation in mammalian cells. When these cells are transformed by the polyoma virus, higher tyrosine activity is observed in the cellular matrix, which is also correlated to cellular proliferation. Another virus that targets tyrosine kinase is the Rous sarcoma virus, a retrovirus that causes sarcoma in chickens. Infected cells display obvious structure modifications and cell growth regulation that is extremely unusual. Protein tyrosine kinases that are encoded by the Rous sarcoma virus cause cellular transformation, and are termed oncoproteins. In addition, tyrosine kinase can sometimes function incorrectly in such a way that leads to non-small cell lung cancer. A common, widespread cancer, non-small cell lung cancer is the cause of death in more people than the total number in breast, colorectal, and prostate cancer together.

Research has shown that protein phosphorylation occurs on residues of tyrosine by both transmembrane receptor- and membrane-associated protein tyrosine kinases in normal cells. Phosphorylation plays a significant role in cellular signalling that regulates the number and variety of growth factors. This is evidenced by the observation that cells affected by the Rous sarcoma virus display obvious structural modifications and a total lack of normal cell growth regulation. Rous sarcoma virus-encoded oncoproteins are protein tyrosine kinases that are the cause of, and are required for, this cellular transformation. Tyrosine phosphorylation activity also increases or decreases in conjunction with changes in cell composition and growth regulation. In this way, a certain transformation exhibited by cells is dependent on a role that tyrosine kinase demonstrates. Protein tyrosine kinases, have a major role in the activation of lymphocytes. In addition, they are functional in mediating communication pathways in cell types such as adrenal chromaffin, platelets, and neural cells.

Tyrosine kinase can become an unregulated enzyme within an organism due to influences discussed, such as mutations and more. This behavior causes havoc; essential processes become disorganized. Systems on which the organism relies malfunction, resulting often in cancers. Of course, the possibility of preventing this type of circumstance is a highly desirable notion to those that are able to conduct related research. Much research has already noted the significant effect that inhibitors of the radically functioning protein tyrosine kinase enzymes have on related ailments. Encouragingly, research has been seen as quite prolific in a number of different cases.