Serial transplantation extends the model beyond the initial implantation by transferring established tumor material into additional host mice. This process is associated with monitoring continued engraftment and growth, helping researchers maintain a usable experimental system. It also supports repeated evaluation of tumor behavior and treatment response across studies once the model has been established.
PDX models can retain clinically relevant features such as tumor heterogeneity, histology, and aspects of treatment response. Preserving heterogeneity is important because a patient’s tumor may contain distinct cellular populations, while retained histology helps researchers examine tissue features in an experimental setting. Together, these characteristics make the models useful for studying tumor biology and therapy effects.
Because PDX hosts lack a fully functional human immune system, the models cannot represent every aspect of cancer biology or treatment response. This limitation is particularly relevant when an application depends on interactions involving the human immune system. Researchers therefore need to interpret findings within the model’s scope rather than treating every result as a complete representation of patient disease.
The workflow begins with collection of a fresh tumor specimen, followed by implantation of tumor fragments or cells into an immunodeficient animal. Researchers then monitor whether the tissue engrafts and how it grows. When an established model is available, serial transplantation can be used to continue the model and support subsequent cancer research experiments.
Once a tumor has engrafted and produced an established model, researchers can use it for preclinical evaluation of anticancer drugs. The same platform also supports testing combination therapies, allowing treatment responses to be examined in tumor material that may retain clinically relevant heterogeneity and histology. These studies provide experimental evidence before therapies are considered in broader settings.
PDX models may help inform personalized treatment strategies by preserving selected features of an individual patient’s tumor and allowing treatment responses to be studied experimentally. Their value is strongest when researchers connect model behavior with the original cancer’s characteristics. However, conclusions remain limited by the absence of a fully functional human immune system and should be interpreted accordingly.