Establishment of Uveal Melanoma Patient-Derived Organoids Using an Air-Liquid Interface System for Translational Research.

Purpose: Uveal melanoma (UM) is the most common primary intraocular malignancy in adults, with a unique genetic and epigenetic profile and a high metastatic risk. The lack of experimental models to replicate tumor biology, including its epigenetic landscape, limits progress in translational research. Recently, patient-derived organoid (PDO) models have emerged as a promising tool for the modeling of various tumors, including UM. This study aims to establish an air-liquid interface (ALI) PDO culture system for UM, evaluate its similarity to the primary tumors, and assess its utility for drug screening. Methods: Fresh and cryopreserved tissue samples from primary UM of 5 patients were cultured using a protocol previously validated for other malignancies. The subsequent characterization of the ALI PDOs included histologic and immunohistochemical evaluation, DNA and RNA sequencing, and histone posttranslational modification (HPTM) analysis. The model's drug-screening potential was evaluated by treating ALI PDOs with the histone deacetylase inhibitor quisinostat and comparing their responses with those of controls. Results: UM ALI PDOs were successfully established and retained their original tumors' immunophenotype and genetic variants. Gene expression profiling revealed similarities between PDOs and primary tumors, with main differences consisting of microenvironment-related signals. Epigenetic analysis confirmed that the overall HPTM landscape remained preserved. Treatment of the PDOs with quisinostat led to transcriptional reprogramming and the expected epigenetic response, with increased acetylation marks. Conclusions: The UM ALI PDO model recapitulates the genetic and epigenetic features of primary UM and holds promise as a platform for future molecular studies and the testing of personalized therapy strategies.