Cellulose microfiber-mediated mesoscale architecture promotes the expansion of patient-derived lung cancer organoids while preserving their malignant characteristics.

The crucial role of mesoscale collagen architecture in establishing and expanding patient-derived tumor organoids is well recognized. However, obtaining sufficient mesoscale collagen bundles from patient cancer tissues is challenging due to the limited availability of such bundles, which depends on the tumor tissue size and digestion efficiency. In this study, we employed cellulose microfibers (CMFs) with micron-scale thickness to mimic the mesoscale collagen architecture and developed a biomimetic hydrogel termed MF-gel by combining CMFs with microbial transglutaminase-cross-linked gelatin for culturing lung cancer organoids (LCOs). Our findings demonstrate that LCOs cultured within MF-gel exhibit increased quantity and size compared to those cultured within gels lacking CMFs. LCOs formed within MF-gel also display irregular morphology and an aggressive phenotype, whereas those grown without CMFs maintain a uniform and spherical appearance. Comprehensive histopathological analysis and gene profiling confirm that LCOs in MF-gel faithfully preserve the histological morphology and genomic landscapes of their parental tumors. Furthermore, MF-gel reliably recapitulates patient-specific drug sensitivity. The MF-gel platform offers significant opportunities for expanding LCOs and studying lung cancer biology, and serves as a potential tool for precision medicine.