Cancer cells spread in the body in a more frightening way than you think

Cancer cells have terrifying metastasis when they can enter the smallest blood vessels to move to the whole body, according to a recent study by scientists from Massachusetts General Hospital. . Finding a way to prevent their spread will help reduce the alarming growth rate of the world's number one killer disease: cancer.

Cancer spreads throughout the body when a cell separates from the original tumor and enters the bloodstream. Metastasis is the main cause of cancer-related deaths. Scientists believe the larger group of cancer cells are unable to penetrate through tiny blood vessels. However, the MGH team proved the opposite.

Cancer cell groups know how to change the structure to fit into small environments. They will change into a chain structure and pass through narrowed blood vessels. After that, the cells will refactor as their original form. The research team has published research results on the Proceedings of the National Academy of Sciences.

Cancer tumors can separate and move to many different parts of the human body.

"This finding will help us better understand the metastatic mechanism of cancer cells , as well as find more effective treatments," said research leader Sam Au.

Scientists have long suspected that the group of cells called "circulatory cancer cells" (CTC) plays a key role in spreading cancer cells. Previous studies have found the existence of relatively large cell groups in the blood vessels of the arm of a patient who died of cancer. This group of cells is located farther away from the area of ​​the original tumor. That means, they have moved through very small capillaries.

However, scientists have not been able to give an accurate judgment on how cell groups do that because obviously, they are much larger than blood vessels.These cells are quite rare ; therefore, it is difficult to detect and separate them from billions of cells floating in blood vessels: red blood cells, white blood cells and mainly platelets . It's like having to find a needle in a haystack. Therefore, researchers are still headache to find a more reasonable solution.

To separate the cells for research, the MGH has relied on micro-channel technology, also known as "chip research labs , " a well-known tool for diagnostic work because they are Able to quickly process large amounts of blood. With such chips, you can remove "grass" to find "the needle" through the process of digestion. They will gradually remove other cells until only circulating cancer cells remain.

Last year, co-author Mehmet Toners used a chip to confirm that such groups of cancer cells are more common in blood vessels than we ever knew. With the latest research, the team of scientists designed a channel with a bottleneck similar in size to a capillary. They then recorded the movement of the CTC cell group through that channel.

Usually, patients with cancer will die because of the metastasis of the original tumor.

To facilitate research, the MGH group injected human CTC cells into the blood vessels of zebrafish embryos. This fish was chosen to conduct research because of the construction of transparent blood vessels to make recording and observation easier. Besides, they also have capillary size similar to humans. In both cases, the cell group was transformed into a chain to penetrate the narrowed portion. After that, they will reconstruct into the original cell group. The study also found similar results with larger CTC groups.

Cancer cells bind together very closely. In this case, the previously existing bonds combine smoothly so that they can easily change the structure without damaging individual cells or disabling cell division in the future.

By understanding part of the mechanism of the spread of cancer cells, scientists hope to be able to control the rate of metastasis by breaking connections or making them unable to change the structure. Thus, cancer cells will not be able to spread through narrow capillaries.