Using state of the art technology, researchers at the University of Copenhagen in Denmark have pinpointed molecular mechanisms that they suspect play an important role in breast cancer cell growth and spread (metastasis).
The researchers write about their findings in a recently published issue of the journal Molecular Cell, and they say their discovery may open new avenues for developing targeted drugs and treatments tailored to individual patients.
The surface of every cell is covered with receptors, tiny "switchboards" that control communication between the cell and the world around it.
For instance, only certain proteins are able to dock onto the receptors and thereby deliver molecular signals relevant to particular cell processes, such as growth, division, making of proteins and death.
In this latest study, the Danish team, led by professor and protein researcher Jesper Velgaard Olsen, investigated a cell surface receptor that is known to be important for health and disease, the so-called FGFR2b receptor.
FGFR2b is a fibroblast growth factor receptor that plays an important role in the development of internal organs in the embryo, and the lungs in particular.
If an FGFR2b signal goes wrong, this affects normal development of lung tissue. There is also evidence of FGFR2b playing a role in certain types of breast cancer, write the researchers.
They discovered two signaling proteins that bind to FGFR2b with completely different effects: one affects cell division and the other controls cell movement.
Both processes are key to healthy cell development but have serious consequences if they spin out of control, for instance they can spur cancer cell growth and metastases.
Hope for customized treatments in future
Prof. Olsen, who works in the University's Novo Nordisk Foundation Center for Protein Research, explains what they found:
"In simple terms, we have mapped the molecular switch on the receptor that turns two important biological processes on and off, respectively.
We have, in other words, pinpointed the binding site that can cause increased spreading of breast cancer cells and thus the development of metastases."
For their study, the team used state of the art technology to carry out a large-scale experimental analysis of proteins, an approach known as "functional proteomics."
The technology, which includes advanced mass spectrometry, allows rapid investigation of what happens inside cells when selected proteins combine with a chosen receptor.
The new technology gives protein researchers tools that were once only available to geneticists.
"It was previously a huge challenge to analyze proteins - but today we can study thousands of proteins in a very short time," Prof. Olsen says.
Although their investigation was confined to human cancer cells and mouse tissue, he and his team believe their findings will help improve customized treatments for human breast cancers in the long run.
He says the FGFR2b receptor could become a new biomarker for diagnosing and treating cancers:
"The more we know about the body's transmission systems, the better we become at targeting medical treatment. Hopefully, we will in future be able to offer customized treatment based on the individual patient's cellular profile."
Breast cancer is the most common cancer in women. The National Cancer Institute estimates that in the US in 2013 there will be 235,000 new cases of breast cancer, and the disease will claim some 40,000 lives. Most deaths from breast cancer are due to metastasis.
Earlier this year, a team of US researchers revealed how copper depletion therapy showed surprisingly good results in preventing the spread of cancer in high-risk triple-negative breast cancer - a type of breast cancer that is very difficult to treat.