Cell signalling pathways
Development and progression of cancer is driven by dysfunctional signalling pathways that promote tumour growth and invasion. The combined effect of a variety of deregulated key pathways leads to the acquisition of capabilities in cancer that are tightly controlled in normal cells. These altered cellular properties strongly promote cancer cell proliferation and the evasion of cellular growth suppression mechanisms and apoptosis. Cancer-specific alterations in signalling pathways also overcome limitations of cellular replication potential. In late-stage cancers, communication of cancer cells with the tumour microenvironment leads to tissue remodelling and reprogramming, including the formation of new blood vessels and the spread of tumour cells in the body. These complex cellular changes are controlled by a myriad of cellular signalling pathways. The chapter reviews the principal regulatory mechanisms that control key cancer signalling pathways, particularly focusing on pathways that have been successfully targeted in cancer therapy.