'Addicted' cells provide early cancer diagnosis

Scientists at the Institute of Food Research have detected subtle changes that may make the bowel more vulnerable to the development of tumours.

With support from the Food Standards Agency and the Biotechnology and Biological Sciences Research Council they are investigating whether diet could control these changes and delay or reverse the onset of cancer.

"We looked at changes in 18 genes that play a role in the very earliest stages of colorectal cancer," says Professor Ian Johnson at the Institute of Food Research.

"We detected clear chemical differences in these genes in otherwise normal tissue in cancer patients.

"This represents a new way to identify defects that could eventually lead to cancer."

All cells carry a complete set of instructions for the whole organism in their nuclear DNA, but to define the specialised structure and functions of each particular cell type, genes must be switched on or firmly off, over the course of the cell's life-cycle.

One of the mechanisms controlling the activities of the genes in a cell is the "epigenetic code", a set of chemical tags attached to the DNA molecule, marking individual genes for expression, or for silence. It is well known that the abnormal behaviour of cancer cells is partly due to mistakes in this epigenetic code, some of which switch on genes for growth, whilst others switch off genes that would otherwise cause abnormal cells to destroy themselves.

Scientists at IFR are exploring the possibility that such mistakes in the epigenetic code may begin to occur in apparently normal tissues, long before the appearance of a tumour.

In the current study published in the British Journal of Cancer they measured the numbers of methyl groups attached to DNA taken from the cells lining the large intestine of bowel cancer patients. They found subtle changes that may make the whole surface of the bowel more vulnerable to the eventual development of tumours by causing the 'addiction' of cells to abnormal gene expression.

Some of these changes seem to occur naturally with age, but, supported by the Food Standards Agency, IFR is investigating the possibility that factors in our lifestyle such as diet, obesity and exercise can accelerate or delay DNA methylation as we grow older, thus giving us some degree of control over this vital aspect of our long-term health.

Professor Nigel Brown, Director of Science and Technology at BBSRC said: "Basic research in the relatively young field of epigenetics is already contributing to our understanding of human health. Understanding how epigenetic processes work to maintain healthy cells and tissues is the key to long-term health because, as we see here, the breakdown of these normal processes may subsequently cause disease. BBSRC funds a range of research in the field of epigenetics and has been encouraging networking amongst members of the European epigenetics research community."

Source: Norwich BioScience Institutes

Related stories:

Growth factor predicts poor outcome in breast cancer
The response to insulin-like growth factor 1 (IGF-I) in breast cancer cells predicts an aggressive tumor that is less likely to respond to treatment, said researchers at Baylor College of Medicine in a report that appears in the current issue of the Journal of Clinical Oncology. The finding gives impetus to the movement to tailor cancer treatments to attributes of the various tumors.
Location, location, location important for genes, too
Cells become cancerous mainly because they lose control of their growth. To better understand how this happens, a new study at Ohio State University's Comprehensive Cancer Center looks at four genes that help regulate cell growth in embryos and that contribute to cancer in adults.
Variation of normal protein could be key to resistance to common cancer drug
Researchers at the Moores Cancer Center at the University of California, San Diego (UC SD) in La Jolla have found evidence explaining why a common chemotherapy drug, cisplatin, may not always work for every cancer patient. They have shown that when a variant version of a key protein that normally causes cell death is active, patients may be resistant to the cancer-killing drug.
Japanese create stem cells from wisdom teeth
Japanese scientists said Friday they had derived stem cells from wisdom teeth, opening another way to study deadly diseases without the ethical controversy of using embryos.
Senescence in liver cells can provoke a beneficial immune reaction
Although post-reproductive life in humans is often associated with decline and a loss of powers, an analogous state in certain cells -- called senescence -- is proving to be one of ironic potency. Scientists at Cold Spring Harbor Laboratory (CSHL) today reported that a particular class of senescent liver cells orchestrates a sequence of events in living mice that can limit fibrosis, a natural response of the liver to acute damage.
Molecular switch found in mice could lead to future obesity treatments
A surprise discovery -- that calorie-burning brown fat can be produced experimentally from muscle precursor cells in mice -- raises the prospect of new ways to fight obesity and overweight, say scientists from Dana-Farber Cancer Institute.
Study shows how daughter is different from mother
The mother-daughter relationship can be difficult to understand. Why are the two so different? Now a Northwestern University study shows how this happens. In yeast cells, that is.
Researchers discover technology that silences genes
Mount Sinai researchers have developed a new gene silencing technology that could be used to target genes that can lead to the development of certain diseases. This technology could pave the way for preventing diseases where gene dysfunction plays a role.

News discussion:

Medicine & Health news