Abstract PR06: Conditional reprogramming is successful in generating patient-derived stable cell cultures from rare aggressive tumors

Purpose/Objectives: The lack of authenticated cell lines from rare tumors, such as adenoid cystic carcinoma (ACC), have compromised studies on basic biology and drug development. ACC of the salivary gland is a rare human cancer and is classified as a rare or “orphan” disease. It has the propensity for invasion of peripheral nerves or blood vessels early in the disease course resulting in a high incidence of both local and distant metastases to lung and bone. The primary course of treatment is surgical removal of tumor, which is usually combined with postoperative radiotherapy. To date no targeted therapy exists for this tumor type. Patient-derived mouse xenografts (PDX) have been shown to maintain the histology and gene expression profile of the primary tumor, making them a valid model system. However, PDX models suffer from high cost, expensive maintenance, low take rate (30-50%), lack of manipulation and high throughput capability. In order to study these tumor types, a reliable model system is critical that can maintain the key genetic features of the primary tumor. Materials/Methods: A new cell culture method, conditional reprogramming (CR), combines the use of irradiated mouse fibroblasts and a ROCK inhibitor to induce the rapid, efficient, and long-term growth of normal and tumor cells without requiring exogenous viral or cellular gene expression. We used this technology to establish cell cultures from rare tumor types such as ACC, neuroendocrine, anal cancer and recurrent respiratory papillomatosis. Herein, we present data collected on recently established stable cultures for ACC using PDX tissue materials. We tested the maintenance of metastasis in the cell lines by establishing a rapid and robust in-vivo zebrafish xenograft model system for ACCs, using ACC11 as a prototype. Results: We generated stable cultures for ACC from eight individual PDX tumors using CRC technology. We demonstrate that these cultures maintain the key genetic features of the primary tumors. One ACC cell line, ACC11, has shown to maintain the MYB-NFIB translocation, oncogenic mutations in FGFR2 and ATM genes and overexpression of Myb-NF1B fusion protein similar to the tumor of origin (PDX tumor). In the zebrafish in-vivo system, these cells are migratory and possess metastatic potential demonstrated by migration of tumor cells from the 2-day post fertilized yolk sac to the tail including vascular invasion within 3 days post injection. Similar results were obtained when PDX tissue material for ACC11 as well as a conventional metastatic breast cancer cell line, MDA-MB231. In contrast, injection of a patient-derived normal breast cell line established using the CR technology and a conventional non-metastatic breast cancer cell line, MCF7, did not show any movement of cells even after 7 days of post injection. Conclusions: We have successfully established a tool-kit consisting of an in-vitro (cell line) and a rapid in-vivo (zebrafish) metastasis model system for biological and translational research of rare tumor types. The use of this novel CR method has great potential in rapidly generating patient-derived normal and cancer primary cells for a wide variety of uses including biobanking, basic tumor biology, drug target identification, and drug discovery, with an ultimate goal of personalized cancer medicine. This abstract is also being presented as Poster B27. Citation Format: Chen Chen, Sujata Choudhury, Devan Wilkins, Eric Glasgow, Richard Schlegel, Seema Agarwal. Conditional reprogramming is successful in generating patient-derived stable cell cultures from rare aggressive tumors. [abstract]. In: Proceedings of the AACR Special Conference: Patient-Derived Cancer Models: Present and Future Applications from Basic Science to the Clinic; Feb 11-14, 2016; New Orleans, LA. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(16_Suppl):Abstract nr PR06.