Women with high grade serous ovarian carcinoma (HGSOC) are presented with a daunting outcome, poor prognosis and a fatal resistance following first line treatment. In order to more effectively treat these women, the underlying mechanisms and vulnerabilities of this disease must be understood.
A genetically engineered mouse model (GEMM) was developed, driving the over-expression of MYCN or LIN28B to the fallopian tube secretory epithelial cells (FTSEC) together with a mutant P53 to mimic the aggressive C5 subtype of HGSOC in mice. The GEMM successfully developed tumours however these occurred with low frequency and long latency, suggesting additional oncogenic events are required. Therefore, we investigated whether CRISPR/Cas9 RNP complexes introduced into FTSEC cell lines by nucleofection could provide the third oncogenic hit required for HGSOC tumorigenesis. As a proof of principle PTEN was targeted. Loss of PTEN resulted in efficient tumour development and relatively quickly, within 3-4 months. CRISPR/Cas9 mediated insertions and deletions in PTEN were confirmed by MiSeq analysis. This method can now be used to generate new GEMM of HGSOC or to screen for other genetic events that promote tumorigenesis.