How Cancer Cells Travel and Survive in the Bloodstream

Cancer is deadly because it spreads to other parts of the body. This spreading, or metastasis, happens when cancer cells leave the original tumor and travel through the bloodstream to form new tumors elsewhere. But, this journey is tough. Most cancer cells don't survive the trip. They have to squeeze into tiny blood vessels, stick to the vessel walls, and squeeze out again to reach distant organs. Only a few make it. This journey is influenced by the circulating tumor microenvironment (cTME). Think of it as the environment that cancer cells face while traveling in the blood. It's different from the environment in the original tumor or the new organ they're trying to invade. The cTME includes things like blood cells, proteins, and other factors that affect how cancer cells behave while they're on the move. The cTME is important because it could help us find new ways to fight cancer. By understanding how it works, we might be able to stop cancer cells from spreading. It could also help us predict how well a patient will do. If we know what's happening in the cTME, we might be able to figure out if a patient's cancer is likely to spread or not. The cTME is a complex network of different things. It includes physical factors, like the flow of blood, and biological factors, like the types of cells and proteins present. These things all interact with each other in ways that can help or hinder cancer cells. For example, certain blood cells might help cancer cells stick to the vessel walls, while other factors might help them squeeze out and invade new tissue. The cTME is a hot topic in cancer research. Scientists are trying to figure out how it works and how we can use it to our advantage. They're looking for ways to target the cTME to stop cancer cells from spreading. They're also looking for ways to use the cTME as a biomarker. A biomarker is something that can be measured to give us information about a disease. In this case, the cTME could help us predict how well a patient will do or how well a treatment will work.