Some cells secrete substances that can promote their own or other cells’ growth. These substances are called growth factors. Growth factors achieve this effect through their bond with receptors located on the cell surface, named membrane receptors. Each growth factor binds itself to its specific receptor, due to the structural complementarity between the two molecules, like a lock and key system.
Once the growth factor is bound to its own receptor, it triggers a series of chemical reactions inside the cell, culminating with the expression of genes that will activate functions such as cell proliferation or angiogenesis.
To allow this series of chemical reactions, the presence of tyrosine kinase protein is essential. As such, inhibiting tyrosine kinase stops signal transmissions among the growth factor, its receptor, the interior of the cell and the genes, preventing stimulus to cell proliferation and angiogenesis.
Tyrosine kinase inhibitors belong to the molecular target drug class and have been used for kidney, lung, head and neck cancers, aside from certain sarcomas and hematologic neoplasm.
To find out more about molecular target drugs, refer to the “FAQ – molecular target drugs” section.