Development, Characterization, and Therapeutic Utility of Paclitaxel‐Resistant Breast and Gastric Cancer In Vitro and In Vivo Models

Abstract Paclitaxel, one of the most commonly used anticancer agents, is employed in the treatment of a range of malignant tumors. However, resistance is one of the major barriers to successful therapy. Despite its clinical relevance, the molecular mechanisms underlying paclitaxel resistance remain poorly understood. In this protocol, we describe the methods for establishing paclitaxel‐resistant tumor models both in vitro and in vivo, and how we investigated the underlying mechanisms of resistance. Additionally, we evaluated the potential of combination therapies to overcome paclitaxel resistance in these models. © 2025 Wiley Periodicals LLC. Basic Protocol 1 : Generation of paclitaxel‐resistant breast cancer model in vivo. Basic Protocol 2 : Generation of paclitaxel‐resistant gastric cancer model in vitro. Basic Protocol 3 : Validation of drug resistance in vivo. Basic Protocol 4 : In vitro and in vivo evaluation of combination therapy in paclitaxel‐resistant models.