Apoptosis Pathways and Chemotherapy in Brain Tumors

Apoptosis, the major programed cell death pathway, is a mechanism of both normal homeostasis and disease. In the context of tumors, the apoptotic machinery is altered to favor tumor expansion despite harsh microenvironmental conditions and therapeutic interventions aimed at inducing cell death. Insights into both the basic and the neoplastic regulation of apoptosis have opened up therapeutic strategies that have already reached the clinic with their full implication yet to be realized. The main objective of this chapter is to review the molecular mechanisms of apoptosis, as well as provide an overview of the existing knowledge of how apoptosis is deregulated in glioblastoma, how it impacts the tumor environment and response to chemotherapy, as well as novel approaches to trigger apoptosis in brain tumors.