Bergen research group adopts nanotechnology for cancer research

Mar 24 2010

Biomedical researchers in Bergen are applying nanotechnology to mimic the body's natural processes, create new blood vessels to supply engineered tissue, and deepen our understanding of cancer.

Effective combination

Biomedical researchers around the globe are going all-out to induce cells to create new tissue. But all living tissues require a supply of blood to survive. Professor James Lorens and his team at the University of Bergen's Department of Biomedicine are using nanotechnology to study how to make cells form new blood vessels, both within the patient's body and in the laboratory. In the next phase the team will use this knowledge to investigate the molecular mechanisms that govern the progression of cancer.

The recipe sounds straightforward enough: mix together one portion of endothelial cells (which form vascular walls), one of smooth muscle cells (which form the vessels' reinforcing exterior walls) and one of matrix proteins (which surround tissue cells and form connective tissue throughout the body). Let these "simmer" for a few days under the right conditions, and voilà the cells grow together to form a network of blood vessels.

Mimicking bodily processes

The Bergen research group studies how cells interact with each other and with synthetic biomaterials on the nano-level. The aim is to understand and copy the cells' natural processes - an essential of regenerative medicine and the engineering of new tissue.

"An ideal implant," explains Professor Lorens, "should mimic the body's natural tissues and send proliferation and differentiation signals to the cells. The nanoscale topology is vital for controlling how this occurs."

The implant as a scaffold for growth

Nanotechnology opens up new opportunities for engineering biomaterials that control cell development so that new tissue grows inside an implant or attaches to it. The implant functions as a growth scaffold in an area of the body where a cavity has been left by an injury or disease - such as when stem cells form new bone tissue to replace bone that has been damaged or removed.

"A primary challenge with any tissue formation, however, is securing the blood supply to the new tissue," emphasises the professor. "In other words, making sure that blood vessels are formed within the tissue."

Self-building blood vessels

In light of this, the Bergen group is taking a particularly close look at the processes by which blood vessels are formed in the body.

"Our goal is to place the three blood vessel components (epithelial and smooth muscle cells, and matrix proteins) into an implant where cells are connecting to new tissue," says Professor Lorens.

His team has successfully induced this process both in Petri dishes and in small sponge-like implants in laboratory animals.

"We have demonstrated vessel formation in synthetic implants in our lab animals. In the next phase, we'll examine more specific tissue types such as bone tissue, for example."

Directing communication between cells

What a cell develops into is determined by signals it receives from its immediate surroundings and other cells nearby.

"One aspect we're studying is how various cell types communicate - endothelial and smooth muscle cells in our case - and how we can use this when we want blood vessels to form."

The group is also examining ways of employing nanotechnology to direct cell communication - by placing cells on a nanostructured biomaterial that has been surface-treated with specific molecules known to give off certain signals to the cells. The researchers are looking at how certain nanostructured surfaces affect blood vessel formation.

"We need a better understanding of how cells perceive nanofabricated surfaces and how this affects communication between cells," explains Professor Lorens. "By reproducing the signals that cells encounter from their immediate surroundings inside the body's various tissues, we can control how the cells proliferate and differentiate."

Application as a cancer treatment?

One of the world's few research groups to utilise this technology, the Bergen group studies how these processes occur in diseased tissue such as cancerous tumours. Cancer cells develop in harmful ways because they do not detect signals in the same fashion as do healthy cells.

"With tissue engineering," continues the professor, "we can reproduce a tumour in order to study how it interacts with blood vessels. If we succeed in cutting the blood supply to the tumour, it will starve and die."

"Tumour tissue engineering can also help us to understand how cancer cells spread via blood circulation," he adds. A December 2009 article in the Proceedings of the National Academy of Sciences of the United States of America describes how Professor Lorens' team used the tumour tissue engineering technique to characterise a new gene that regulates the spread of breast cancer.

Active in EU-funded research

The Bergen research group has built up a large international network and participates in several major projects funded by the EU.

The group, together with researchers from the university's Department of Clinical Dentistry, are participating in the major integrated project VascuBone, the objective of which is to improve the formation of blood vessels during regeneration of new bone tissue.

Professor Lorens' team also is involved in an EU collaboration seeking new medications that can block the blood supply to various types of cancerous tissue. These efforts are based on the idea that it is possible to starve the cancerous tumour by stopping its blood supply.

"More biologists and biomedical specialists should apply nanotechnology to study molecular mechanisms that govern the progression of disease. Multidisciplinary research like this holds great potential - but accomplishing the objectives will require active coordination and dedicated funding schemes," concludes Professor Lorens.

The Bergen research group receive funding for this valuable work under the Research Council programme Nanotechnology and New Materials (NANOMAT). Seven per cent of the NANOMAT programme's budget is allocated to health-related projects.