How Tumor Cells Create Their Own Pathways
In 90 percent of cancer deaths today, the actual cause of death is no longer the patient’s original tumor but rather metastases. Metastasis occurs when tumor cells “migrate” to other organs through the bloodstream. Scientists have now discovered the trick tumor cells use to invade tissue from the blood vessels: They produce signaling proteins to make the arterial walls permeable — thus clearing their pathway to a different organ.
The latest findings are published in the current issue of the journal Cancer Cell.
How does a tumor cell set up a signaling pathway in order to metastasize? Scientists at Technische Universität München’s (TUM) Klinikum rechts der Isar and Helmholtz Zentrum München have made a significant discovery in this area by studying colon cancer. They have learned that the tumor cells release certain proteins known as chemokines. In the case of metastatic colon cancer cells, the chemokine concerned is CCL2. The CCL2 chemokine docks on to the cells of the inner blood vessel walls (endothelial cells) and activates the corresponding receptor (CCR2 receptor). This connection makes the endothelial cells permeable — creating a clear path for the tumor cells.