Apoptosis and tumourigenesis.

Avoidance of apoptosis is a cornerstone of tumourigenesis. The functions of key molecules that either sense DNA damage or that commit cells to die are lost during tumorigenesis. Frequently, during tumourigenesis, cells increase their survival signals. The initiation of apoptosis by DNA damage signals was shown to absolutely depend on the expression of either Bax or Bak. Single oncogenes, such as BCR-ABL, which provide survival signals, were argued to be sufficient to support the oncogenic state; suppression-induced apoptosis and tumour regression in vivo. The concept of tumour maintenance by a single oncogene, inhibiting apoptosis, is of interest.