(502e) Zwitterionic 3D Culture Matrix Reduces Symbolic Gene Differential Expression in Prostate Cancer Organoids

Neuroendocrine prostate cancer (CRPC-NEPC) is one of the most aggressive subtypes among all prostate cancer subtypes, and currently there are no target therapies for this disease available. A major hindrance to therapy development is that there is not an accurate disease model available for researchers and clinicians to understand the oncologic transformation mechanism that results in clinical heterogeneity. Matrigel is a naturally derived material that has been shown to promote organoid growth and self-assembly. However, its xenogeneic source and batch-to-batch variation severely limit its use. Furthermore, animal-derived matrices are not suitable for translational applications due to risks of immunogen and pathogen transfer. Here, we report a novel zwitterionic polycarboxybetaine (PCB) 3D culture matrix for CRPC-NEPC organoid culture. Zwitterionic materials are known to be superhydrophilic and utilized in various biomedical applications for anti-fouling purposes. As synthetic materials, many properties of culture matrices such as mechanical stiffness, degradation rate, type, and concentration of cell-adhesion peptides, can be fine-tuned based on different organoid disease models. The prostate cancer organoids cultured in an optimized PCB hydrogel group incorporated with fibronectin-mimicking peptides with higher stiffness express similar levels of marker mRNAs and proteins, while showing a higher proliferation profile and larger organoid diameter, indicating that CRPC-NEPC organoids exhibit a more pronounced preference for our pure zwitterionic culture system. Additionally, qPCR results also show that the expression levels of marker genes in the PCB group are less differentially expressed than that in the Matrigel group after multiple passages, indicating that the zwitterionic culture system is giving less background noise to organoids during culture due to its superhydrophilicity and lack of many unwanted peptides. This zwitterionic culture system can offer great opportunities in various organoid disease models and subsequent applications.