A specific type of colon cancer cell capable of initiating tumour growth in mice is identified and characterized in a pair of related papers to be published online in Nature. Both papers lend support to the theory that, within a tumour, only a subset of cells - cancer stem cells - are responsible for tumour formation and maintenance.
John Dick and colleagues studied tumour growth by implanting human colon cancer cells under the kidney capsule of mice with a deficient immune system. They report that only a small population of these cells was able to initiate tumour growth and that these cells are found in the subset of colon cancer cells that express the cell surface protein CD133. This protein has previously been implicated as a marker for brain and prostate cancer stem cells. Ruggero De Maria and colleagues show that human colon cancer cells expressing CD133 also cause tumour growth when injected under the skin of immunodeficient mice.
These studies demonstrate that a small population of colon cancer cells, distinct from those that make up the bulk of a tumour, initiate tumour growth. The authors propose that the approaches used to identify and characterize these cells might aid future attempts to understand the processes involved in colon cancer and develop novel therapeutic strategies to treat the disease.
John Dick (University Health Network, Toronto, Canada)
Ruggero De Maria (Istituto Superiore di Sanità, Rome, Italy)
Abstracts available online:
(C) Nature press release.
Message posted by: Trevor M. D'Souza