Stem-cell driven cancer: "Hands-off" regulation of cancer development

Abstract

A cancer dogma states that inactivation of oncogene(s) can cause cancer remission, implying that oncogenes are the Achilles' heel of cancers. This current "hands on" model of cancer has kept oncogenes firmly in focus as therapeutic targets and is in agreement with the fact that in human cancers all cancerous cells, with independence of the cellular heterogeneity existing within the tumor, carry the same oncogenic genetic lesions. This rule has now been broken in a study of the effect of the BCR-ABL oncogene in cancer development in a mouse model in which oncogene expression is restricted to the stem cell compartment. BCR-ABL is linked to chronic myeloid leukemia (CML) disease in humans, and this study shows that by limiting the oncogene expression to Sca1+ cells CML arises, indicating that maintenance of oncogene expression is not critical for the generation of differentiated tumor cells and showing a "hands off" role for BCR-ABL in regulating cancer formation. Here we provide an update on the use of this system for modeling human cancer and its potential application for therapeutic targeting of cancer stem cells (CSCs) and the hands-off function of oncogenes. ©2009 Landes Bioscience.