Normal stem cells and cancer stem cells have similar properties, such as self-renewal (the ability to make copies of itself) and differentiation (the ability to form specialized cell types), and researchers are currently trying to discover if the same genes are active in both types of cells.
There is debate within the scientific community as to whether cancer stem cells even exist, with some arguing that these are simply cancer cells that have developed some stem cell-like qualities, or normal stem cells that have acquired cancerous properties.