Receptor tyrosine kinase signalling as a target for cancer intervention strategies.

In multicellular organisms, communication between individual cells is essential for the regulation and coordination of complex cellular processes such as growth, differentiation, migration and apoptosis. The plethora of signal transduction networks mediating these biological processes is regulated in part by polypeptide growth factors that can generate signals by activating cell surface receptors either in paracrine or autocrine manner. The primary mediators of such physiological cell responses are receptor tyrosine kinases (RTKs) that couple ligand binding to downstream signalling cascades and gene transcription. Investigations over the past 18 years have revealed that RTKs are not only key regulators of normal cellular processes but are also critically involved in the development and progression of human cancers. Therefore, signalling pathways controlled by tyrosine kinases offer unique opportunities for pharmaco logical intervention. The aim of this review is to give a broad overview of RTK signalling involved in tumorigenesis and the possibility of target-selective intervention for anti-cancer therapy.