Metastases in the microchip
A "training chamber" was created for metastases
Kirill Stasevich, Compulenta
We know quite a lot about how cancer forms metastases, but usually metastasis is investigated "in general", paying attention first of all to those features that any type of tumor has. However, cancer settles in a variety of tissues: in the liver, in the bones, in the lungs, etc., and it would be strange to believe that in each case metastases behave the same way.
But how to study the features of the penetration of metastases, for example, into bone tissue? Researchers from the Massachusetts Institute of Technology (USA), together with colleagues from Italy and South Korea, have created a microchip simulating bone tissue with vessels, into which cancer cells can be launched and their behavior monitored.
Photo by Jessie Jeon / MIT
The microchip consists of microchannels that are filled with epithelial and bone cells: this is how a blood vessel surrounded by bone was imitated. Metastatic breast cancer cells were injected into the endothelial "vessel", and a day later it was possible to see how malignant cells passed from the endothelial vascular part of the microchip to the bone. After five days, they formed microclusters consisting of several dozen cells: a micro-tumor was obtained.
Bone cells (green), vascular endothelium (red) and tumors (blue)
in a metastatic microchip (photo by Jessie Jeon / MIT).
Scientists tried to find out at the same time whether the bone-cell environment can be replaced with a simple collagen matrix. It turned out that cancer cells go twice as bad in such a matrix and do not go far into it.
In the journal Biomaterials (Bersini et al., A microfluidic 3D in vitro model for specificity of breast cancer metastasis to bone), the authors write that the activity of metastatic cells depended on the protein CXCL5 secreted by bone cells and on the protein CXCR2, which sits on the membranes of cancer cells and catches CXCL5. The role of these proteins in metastatic processes has been discussed for a long time, and in the end it became necessary to find out whether this pair works in each specific case – for example, when cancer enters the bone.
When the researchers blocked the activity of cancer CXCR2 with the help of antibodies, metastatic cells stopped penetrating through the "blood vessel" into the microchip "bone". And when CXCL5 was injected into the collagen matrix, cancer cells began to tear into it as if there were real bone cells there. Apparently, if you act with some kind of medicine on these proteins, you can significantly suppress tumor metastasis.
In general, researchers believe that their device will greatly advance the study of metastases, because with the help of a microchip, the whole process can be observed in three-dimensional form and at all stages of cell introduction into new tissue.
In the future, they want to adapt this method to other tissues. So, it is known that cancer enters the muscles reluctantly, and scientists hope to find out why with the help of their development.
Prepared based on the materials of MIT News: A microchip for metastasis.
Portal "Eternal youth" http://vechnayamolodost.ru07.02.2014