Abstract
<jats:p>Traditional preclinical tumor models have limited predictive capabilities, hindering effective translation in nano-oncology. To address this, integration of advanced in vitro systems with patient-derived xenograft (PDX) models provides a robust pathway. This chapter presents an overview of two-dimensional and three-dimensional in vitro models, microfluidic tumor-on-chip systems, and in vivo approaches, with emphasis on sustainability-driven strategies. These platforms assess efficacy, biodistribution, pharmacokinetics, and safety of green-synthesized and biodegradable nanomaterials. PDX models are highlighted for their ability to preserve tumor heterogeneity and patient-specific molecular features, enabling more precise therapeutic evaluation. Key challenges, including scalability, ethical considerations, and regulatory requirements, are discussed alongside emerging trends such as humanized PDX models and artificial intelligence-based translational approaches. Overall, this chapter highlights a continuum bridging preclinical research and clinical application in nano-oncology.</jats:p>