New York, Oct 7 (IANS): Researchers have developed a novel testing platform to evaluate how breast cancer cells respond to the recurrent stretching that occurs in the lungs during breathing.

The technology is designed to better understand the effects that the local tissue has on metastatic breast cancer to study how metastases grow in new tissue, the study, published in the journal Advanced Functional Materials reported.

"One of the key features of breast cancer is that most patients survive if the disease stays local, but there is a greater than 70 per cent drop in survival if the cells have metastasized," said study author Luis Solorio from Purdue University in the US.

However, once the cells leave the primary tumour, they are often no longer responsive to the drugs that initially worked for the patient.

"We wanted to develop a system that could help us better understand how the physiology of a new tissue space affected tumour cells upon invasion into the new organ," Solorio added.

The researchers created a magnetically moving cell culturing system where the cancer cells can be grown in 3D on a suspended extracellular matrix protein that is abundant in early metastatic lung tissue in order to evaluate the impact of mechanical forces.

They were able to incorporate the strain amplitude and rate of breathing in this tissue mimic. The researchers found that the cells quit dividing under these conditions.

"Never before has the concept of motion been interrogated as a component of the tumour microenvironment," said researcher Michael Wendt.

"We now understand that healthy organs utilize motion to resist metastatic colonization," Wendt added.

The development of this microactuator system will not only continue to yield increased biological understanding of metastasis, but it will also serve as a platform to better evaluate pharmacological inhibitors of the most lethal aspect of cancer progression.

According to the researchers, this is the first attempt to engineer a cell culture system that can apply mechanical forces on a suspended tissue.

"Our system better mimics the physiological environment without using artificial substrates. Using this platform, we show that certain cancer cells slow down their proliferation due to the cyclic stretching of breathing," they wrote.