The Mayo Clinic Brain Tumor Patient-Derived Xenograft National Resource characterizes and provides phenotypic and molecular information about patient-derived xenograft (PDX) cell lines. We also provide services related to genome-wide profiling data, tumor extracts, frozen PDX tumor tissue, cryopreserved PDX tissue and derivative PDX cell lines.

By giving other researchers the tools to readily identify tumor lines of greatest interest for their own research, we help advance brain tumor and glioblastoma research around the world and move closer to better treatment options for patients.

The Brain Tumor PDX National Resource was launched under the direction of Jann N. Sarkaria, M.D., to provide a highly annotated series of brain tumor PDX models with levels of multi-omic characterizations comparable to those provided for patient tumors by The Cancer Genome Atlas (TCGA). The collection in the Mayo Clinic PDX National Resource is derived almost exclusively from patients with glioblastoma.

Through these and other efforts, the PDX National Resource enhances utilization of these highly characterized tumor models.

Large-scale sequencing studies of glioblastoma tumor samples from patients have generated an unprecedented level of transcriptomic, genomic, methylomic and proteomic data that is freely available to researchers around the world, providing incredible insights into glioma genetics and biology.

However, poor access to clinically relevant tumor models with a similar level of molecular characterization is a critical bottleneck that hampers many investigators from performing follow-on basic and translational studies that could propel glioblastoma research even further.

For example, in the context of precision individualized medicine, the relationship between genotype and drug-response phenotype is vitally important for identifying the best drug for an individual patient. But these relationships are poorly understood for most molecular targets in glioblastoma.

Unraveling these complex relationships requires a concerted effort in the global neuro-oncology research community. Our research team at Mayo Clinic is breaking through this bottleneck.

Our patient-derived xenografts are created by taking tumor samples obtained during surgery and directly implanting them in nude mice in the lab. Resulting xenografts are then serially passaged in immune-deficient mice. Mayo Clinic was a pioneer in this xenograft technique for glioblastoma and established a panel of dozens of PDX models.

We have developed extensive phenotypic characterizations of these models regarding growth in flank and brain and response of orthotopic tumors to various therapies, including standard-of-care radiation, temozolomide and bevacizumab.

The glioblastoma PDX model has become a gold standard for both basic and translational research studies in glioblastoma.

Because a large number of cells can be recovered from established xenografts, even slow-growing tumors can be readily expanded to enable large in vitro or in vivo studies. The Mayo Clinic Brain Tumor PDX models have been widely distributed in the neuro-oncology research community and used in more than 100 peer-reviewed manuscripts.