Biomimetic bone niche reconstructs proliferation-inhibited and therapy-resistant bone-metastatic prostate cancer.

Prostate cancer bone metastases often harbor a rare subset of tumor cells with suppressed proliferation, contributing to therapy resistance and disease relapse. However, the lack of physiologically relevant in vitro models has hindered mechanistic and therapeutic advances. Here, we engineered a 3D bone-like microenvironment by integrating calcium phosphate scaffolds, decellularized extracellular matrix (dECM), mesenchymal stem cells (MSCs), and osteoblasts. This biomimetic niche induced a proliferation-inhibited state in prostate cancer cells, closely mirroring transcriptomic signatures identified from patient-derived single-cell RNA sequencing datasets. Tumor cells in this niche also displayed enzalutamide resistance, accompanied by metabolic reprogramming and activation of pro-survival signaling. This platform provides a clinically relevant tool for modeling bone metastatic prostate cancer and accelerating the development of therapies targeting resistant tumor states.