Researchers in Illinois have for the first time identified human pancreatic cancer stem cells, which they believe to be at the root of the disease.
The finding could lead to new therapies for the disease, which has one of the lowest survival rates of any cancer type.
Stem cells are thought to be the basic building blocks of our bodies, able to turn into any other type of cell.
When transferred into mice, the 'cancer' stem cells appeared to be at least 100 times more cancerous than other pancreatic cells, said lead author Professor Diane Simeone.
"The cells we isolated are quite different from 99 per cent of the millions of other cells in a human pancreatic tumour," she said.
"We think that, based on some preliminary research, standard treatments like chemotherapy and radiation may not be touching these cells.
"If that is why pancreatic cancer is so hard to treat, a new approach might be to design a drug that specifically targets pancreatic cancer stem cells without interfering with normal stem cell function."
Rogue stem cells have now been found in several cancer types, and some scientists believe that they will eventually be found in every type of cancer.
The study was conducted by the University of Michigan Medical Centre and will be published in the February 2007 edition of Cancer Research.
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