Oncopig carcinoma cell lines: A foundation for co-clinical trials

L.A. Rund, K.M. Schachtschneider, R.C. Gaba, D.R. Principe, P. Grippo, R.M. Schwind, H. Ozer, L.B. Schook
American Association for Cancer Research Annual Meeting, April 14-18 2018, Chicago, IL
The Oncopig cancer model (OCM) was developed to support a broad range of solid and liquid tumor malignancies while providing the appropriate anatomical and physiological models for preclinical and co-clinical trials to expedite human clinical trials. the OCM develops tumors following Cre recombinase induced expression of KRASG12D and TP53 R167H transgenes in a temporally and spatially controlled manner. To date, in vitro transformation and in vivo tumor formation of soft tissue sarcomas (STS), hepatocellular carcinoma (HCC), and pancreatic ductal adenocarcinoma (PDAC) have been demonstrated. However, the OCM was designed with the potential to generate cancers of all tissue origins. To demonstrate the potential importance of the OCM, we have successfully isolated and transformed multiple OCM cell types, each a progenitor of clinically relevant human disease. Cell type specific cell isolations were performed, and cells cultured under appropriate conditions. Within the first 48 hours, isolated cells were treated with adenoviral vector encoding Cre recombinase (AdCre) at 200-400 MOI for 5 hours in low serum (5%) medium. Both control and transformed (AdCre treated) cells underwent basic histopathologic screening (H&E staining, immunohistochemical staining for vimentin and cytokeratin), and verification of transgene expression (RT-PCR) and tumoriginicity (xenograft into SCID mice). Cell types isolated include fibroblasts, hepatocytes, pancreatic ductal cells, dermal epithelial cells, splenocytes, ovarian surface epithelial cells, fallopian tube secretory epithelial cells, renal proximal tubule epithelial cells, urinary bladder epithelial cells, bone marrow (without specific cell isolation), and testis (no specific cell isolation). Each cell type was successfully transformed, as shown by in vitro phenotypic changes and tumor formation in vivo. Additional gene expression analysis (RNA-Seq) of the STS and HCC cell lines verified the OCM transformed cells recapitulate transcriptional hallmarks of human cancers. Consistent with human STS, OCM STS cell lines display altered TP53 signaling, Wnt signaling activation, and evidence of epigenetic reprogramming. OCM HCC cell lines show transcriptional evidence of TERT reactivation, apoptosis evasion, angiogenesis activation, and Wnt signaling activation, all similar to human HCC. While not an exhaustive list of Oncopig cell types, we have not encountered cells resistant to malignant transformation through Cre recombinase exposure. These results support the unprecedented potential for modeling of additional cancer types, including colorectal, ovarian, fallopian tube, uterine, renal, bladder, skin, and hematological cancers to support and expand preclinical, translational, and co-clinical investigations.