Patient-Derived Xenograft (PDX)

Patient-Derived Xenograft (PDX) designates preclinical cancer models created by implanting tumour tissue directly from patients into immunocompromised mice, preserving original tumour characteristics including genetic alterations, histopathology, cellular heterogeneity, and stromal components far better than traditional cell line-derived xenografts. These models maintain tumour complexity absent from cultured cell lines that undergo selective adaptation losing original characteristics.

The biopharmaceutical industry increasingly employs PDX models throughout oncology drug development for evaluating candidate compounds against diverse tumour types, understanding mechanisms of drug sensitivity and resistance, and identifying biomarkers predicting treatment response. Model generation involves implanting fresh patient tumour tissue into immunodeficient mice, with serial passaging expanding tumour material. Applications span preclinical efficacy testing, biomarker discovery correlating tumour molecular features with drug sensitivity, and resistance mechanism investigation. Limitations include loss of human immune components preventing evaluation of immunotherapies and questions regarding how well immunocompromised mouse hosts recapitulate immune-competent human microenvironments. As technologies advance enabling rapid model generation and banking initiatives create accessible repositories, PDX models continue serving as valuable preclinical platforms.