Drugs have to be thoroughly tested before patients are allowed to swallow them or doctors to inject them. Will they produce the desired effect? What side effects will occur? In the case of cancer drugs, a new test system in the form of a 3-D tumor model could provide the answers. Dr. Jacqueline Pusch laid the basis for this while writing her Masters thesis at the Fraunhofer Institute for Interfacial Engineering and Biotechnology IGB in Stuttgart, and won the 2nd Hugo Geiger Prize for Life Sciences. “What is unique about this model is that it contains a functioning bloodstream,” says Pusch. “It doesn’t just consist of tumor cells like conventional test systems, but also of endothelial cells which line the vessels. These cells form a natural barrier between the bloodstream and the tumor.” Researchers would no longer need to apply new cancer drugs directly to the tumor cells for testing, but could instead introduce them into the model’s bloodstream. “The active agents then have to overcome the barrier of endothelial cells before they can exit the bloodstream and reach the tumor. Only upon arrival do they begin to work. This model brings us much closer to the natural situation in the body than any previous model.” It may even be possible in future to extract patients’ own cells from the tumor and use them for individualized therapies. After all, different bodies react differently to cancer therapy.