Scientists have found the first “conclusive evidence” of the existence of cancer stem cells in humans, in a discovery which could put an end to years of scientific controversy and pave the way for more effective cancer treatments which could attack the disease “at the root” (…)
The existence of cancer stem cells – mutated stem cells responsible for the development and growth of cancers – has been hypothesised for decades, and their existence in mice was established two years ago. Whether or not they are also responsible for the growth of cancers in humans has remained controversial (…)
The study was carried out in a group of patients with a blood disease which commonly develops into leukaemia, and can only technically prove the existence of cancer stem cells for this particular condition, but the scientists said that “similar” cancer stem cells were likely to lie behind the development of other cancers.
Experts believe the theory of cancer stem cells may be of great importance for future treatments. It suggests that at the root of any cancer are a set of cells responsible for its growth. In theory, if treatments could be developed to specifically target these cells, then a cancer could be eradicated altogether.
“The idea here is that the cancer depends on these stem cells for being able to propagate,” said Dr Petter Woll, of the Weatherall Institute for Molecular Medicine at the University of Oxford. “If we can eliminate the cancer stem cells, it would be like removing a tree by the roots – it won’t grow back, like it would if you removed it by the stem” (…)
The researchers emphasised that their findings did not offer any new treatment for MDS or leukaemia patients. However, Dr Woll said that it did give future researchers “a target” for development of more efficient “cancer stem cell-specific” therapies. However, even if cancer stem cells were eliminated, Dr Woll added, there would still be a chance that genetic mutations could lead to other stem cells later becoming cancer stem cells.
Professor Kamil Kranc, a Cancer Research UK stem cell expert based at the University of Edinburgh, said that the findings were a “a huge leap towards understanding the roots of blood cancers”.
“Cancer stem cells have long been thought to be at the heart of many types of cancers but identifying these rogue cells has been a major challenge,” he said. “The next step will be to find specific drugs that eliminate these unique cells, which could be key to helping more people survive cancer.”
Dr Neil Rodrigues, of the European Cancer Stem Cell Research Institute at Cardiff University, said that the new study was “very important”, as it “precisely defines the provenance and biological composition of the cancer stem cell in MDS.”
“The implications for therapy in MDS itself are important as we could now design curative therapies specifically against the cancer stem cell in this otherwise difficult to treat disease and monitor how effective that treatment is,” he said. “If cancer stem cells are definitively identified in human cancers outside the blood system, then this strategy could similarly be applied to effect cure in a wide range of cancers.”