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" SIA reports quoting The Independent
Researchers at Oxford University and Sweden’s Karolinska Institutet said that their findings were "a vitally important step" in our understanding of how cancers developed and how best to treat them. 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.However, in a new study published in the journal Cancer Cell, an researchers said they had tracked gene mutations responsible for a form of blood cancer back to a distinct set of cells which they say are at the root of the cancer’s spread. 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 15 patients involved in the study had myelodysplastic syndrome (MDS), a blood disorder which causes a drop in the number of healthy blood cells, and develops into acute myeloid leukaemia in around half of all cases.
Researchers investigated malignant cells in the bone marrow of the patients and tracked them over time. Using genetic analysis, they were able to isolate a small and distinct group of MDS cells which were the origin of the cancer-driving DNA changes which were causing the disease to progress.
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.