␤-Catenin is a multifunctional protein, stabilization of which is a critical step in its functional activity. Stabilization can be conferred through several means, including mutations in ␤-catenin, common in many carcinomas. In this article, we explore the effect of viral infection on the ␤-catenin signaling pathway in B lymphocytes, including cell lines derived from lymphomas. Infection by the human tumor virus Epstein-Barr virus (EBV) generates several types of latency with different spectra of latent gene expression that are associated with different malignancies. In type III latency, exemplified by EBV lymphoproliferative diseases, the full range of these viral proteins is expressed, whereas in type I latency, only the EBNA1 protein is expressed and functional. We show that ␤-catenin is rapidly degraded in type I B lymphocytic lines but it is stabilized in type III B cell lines, and that ␤-catenin͞T cell factor transcriptional activity is significantly higher in type III cells. Also we show the association of free cytoplasmic ␤-catenin with deubiquitinating enzymes, which may play a role in ␤-catenin stabilization. Activation of the ␤-catenin͞T cell factor pathway by EBV may contribute to the lymphoproliferation characteristic of type III latency.

Cholangiocarcinoma (CC) is an aggressive malignancy with an inferior prognosis due to limited systemic treatment options. As preclinical models such as CC cell lines are extremely rare, this manuscript reports a protocol of cholangiocarcinoma patient-derived organoid culture as well as a protocol for the transition of 3D organoid lines to 2D cell lines. Tissue samples of non-cancer bile duct and cholangiocarcinoma were obtained during surgical resection. Organoid lines were generated following a standardized protocol. 2D cell lines were generated from established organoid lines following a novel protocol. Subcutaneous and orthotopic patient-derived xenografts were generated from CC organoid lines, histologically examined, and treated using standard CC protocols. Therapeutic responses of organoids and 2D cell lines were examined using standard CC agents. Next-generation exome and RNA sequencing was performed on primary tumors and CC organoid lines. Patient-derived organoids closely recapitulated the original features of the primary tumors on multiple levels. Treatment experiments demonstrated that patient-derived organoids of cholangiocarcinoma and organoid-derived xenografts can be used for the evaluation of novel treatments and may therefore be used in personalized oncology approaches. In summary, this study establishes cholangiocarcinoma organoids and organoid-derived cell lines, thus expanding translational research resources of cholangiocarcinoma.