Cancer Stem Cells hit the News
3rd August 2012
Cancer stem cells are defined as those cells within a tumour that can self-renew and drive tumorigenesis. These rare cancer stem cells have been isolated from a number of human tumours, including haematopoietic, brain, colon and breast cancers. The cancer stem-cell concept has important implications for cancer therapy as doctors often successfully reduce the size of tumours through various therapies, but often patients then suffer a relapse and the tumour regrows.
Some researchers believe that this happens because therapies fail to eradicate a small proportion of cells that drive tumour growth known as cancer stem cells. They believe that these are the cells that should be targeted to eliminate the tumour forever. Evidence for the existence of cancer stem cells has been weak. But now three separate groups of researchers working independently have found direct evidence of cancer stem cells driving tumour growth in brain, gut and skin cancers backing this theory and published 1st and 2nd August 2012.
These three separate studies on mice appear to have confirmed the view that the growth of tumours is driven by cancer stem cells. The researchers claim to have resolved one of the biggest controversies in cancer research and say their work marks a "paradigm shift" in the field. These studies have been published in the journals, Nature and Science;
Nature - News and Views: Published online 01 August 2012
Resolving the stem-cell debate. Richard J. Gilbertson & Trevor A. Graham
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11480.html
Nature - Letter: Published online 01 August 2012
A restricted cell population propagates glioblastoma growth after chemotherapy. Jian Chen, Yanjiao Li, Tzong-Shiue Yu, Renée M. McKay, Dennis K. Burns, Steven G. Kernie & Luis F. Parada
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11287.html
Nature - Letter: Published online 01 August 2012
Defining the mode of tumour growth by clonal analysis. Gregory Driessens, Benjamin Beck, Amélie Caauwe, Benjamin D. Simons & Cédric Blanpain
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11344.html
Science Letter: Published online 01 August 2012
Lineage Tracing Reveals Lgr5+ Stem Cell Activity in Mouse Intestinal Adenomas. Arnout G. Schepers*, Hugo J. Snippert*, Daniel E. Stange, Maaike van den Born, Johan H. van Es, Marc van de Wetering, Hans Clevers‡
http://www.sciencemag.org/content/early/2012/07/31/science.1224676
Nature - News in Focus: Published online 02 August 2012
Cancer Stem Cells tracked. Monya Baker.
http://www.nature.com/news/cancer-stem-cells-tracked-1.11087
The suggestion is that the same may be true of all cancers, which produce solid tumours and the results of this type of research could pave the way for a new approach to treating many cancers.
Although, it may be easier said than done as these newly-identified cancer stem cells are very similar to healthy stem cells responsible for growing and renewing tissue in the body. Any therapy to target cancer stem cells may also destroy healthy tissues. A priority for us will be to see if there are important differences between normal and cancer stem cells so that therapies can distinguish between them. Re-confirmation that these cells exist is an important step in future cancer research.