
Animal models
The Weizmann-Brazil Tumor Bank allows scientists to establish models in which tumors, freshly obtained from patients in the operating room after biopsy or tumor resection, are implanted directly under the skin of genetically engineered animal models in a procedure known as patient-derived xenografts (PDX).
These tumors, which resemble to the greatest possible extent the original tumor growing within the human patient, can then be transferred from the first animal model to additional specimens, eventually propagating the tumors into a large colony - all bearing the same human tumor. This colony provides the researchers with a unique opportunity to perform a large variety of experimental manipulations, in parallel on identical replicas of the original tumor. These manipulations enable the identification of critical genes whose targeting can stop tumor growth or even kill the tumor.
The work of Prof. Yardena Samuels, head of the Weizmann-Brazil Tumor Bank, has already yielded four new PDX mouse strains, and it is hoped that this synergy between the two facilities will generate more use of PDX mice for basic cancer research.
Picture (left): Preparation of a tumor sample extracted from a PDX mouse, prior to implantation into additional animal models.