Conserved pathways of apoptosis in leukemia: A short communication

Abstract

The stem cell nature of leukemia and several other cancers has long been known now. Given that the leukemic blast cells (the large population of aberrantly differentiated blood cancer cells) arise from a rare and quiet population of stem cells called leukemic stem cells (LSCs) which have accumulated multiple mutations in multiple steps spread over the years, the particular hypothesis that cancer results from the loss-of-function mutation in apoptotic gene of the apoptotic pathway would mean that the LSCs and the leukemic blast cells do not undergo apoptosis at all. However, this is not the case; in reality, there are experimental and/or clinical studies showing that the LSCs and the leukemic blast cells do undergo apoptosis in a fully grown cancer, though its rate is less than the proliferation rate. I hypothesize in this article that this apoptosis by itself is significant and its importance cannot be ruled out, though it may not be significant when compared with the apoptosis of blood cells in a healthy person. This means that though leukemia arises through multiple mutations which may include mutations in apoptotic genes too, there are left some conserved pathways of apoptosis in fully grown cancer. A few of these possible conserved pathways of apoptosis in a fully developed leukemia, that I list here, include P53, pro-apoptotic Bcl-2 family members, microRNA, and short interfering RNA.