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bioRxiv · 10.1101/658260

A versatile ES cell-based melanoma mouse modeling platform

Bok, I.·Vera, O.·Xu, X.·Jasani, N.·Nakamura, K.·Reff, J.·Nenci, A.·Gonzalez, J. G.·Karreth, F. A.
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Abstract

The cumbersome and time-consuming process of generating new mouse strains and multi-allelic experimental animals often hinders the use of genetically engineered mouse models (GEMM) in cancer research. Here, we describe the development and validation of an embryonic stem cell (ESC)-GEMM platform for rapid modeling of melanoma in mice. Our platform incorporates twelve clinically relevant genotypes composed of combinations of four driver alleles (LSL-BrafV600E, LSL-NrasQ61R, PtenFlox, Cdkn2aFlox) and regulatory alleles to spatiotemporally control the perturbation of genes-of-interest. Our ESCs produce high contribution chimeras, which recapitulate the melanoma phenotypes of conventionally bred mice. Using our ESC-GEMM platform to modulate Pten expression in melanocytes in vivo, we highlight the utility and advantages of gene depletion by CRISPR-Cas9, RNAi, or conditional knockout for melanoma modeling. Moreover, we use complementary genetic methods to demonstrate the impact of Pten restoration on the prevention and maintenance of Pten-deficient melanomas. Finally, we show that chimera-derived melanoma cell lines retain regulatory allele competency and are a powerful resource to complement ESC-GEMM chimera experiments in vitro and in syngeneic grafts in vivo. Thus, when combined with sophisticated genetic tools, our ESC-GEMM platform enables rapid, high-throughput, and versatile studies aimed at addressing outstanding questions in melanoma biology.

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Bok, I., Vera, O., Xu, X., Jasani, N., Nakamura, K., Reff, J., Nenci, A., Gonzalez, J. G., Karreth, F. A.. 2019-06-03. A versatile ES cell-based melanoma mouse modeling platform. https://doi.org/10.1101/658260

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