A Living Biobank Of Ovarian Cancer Ex Vivo Models Reveals Profound Mitotic Heterogeneity


Year:

Session type:

Theme:

Stephen Taylor1
1University of Manchester

Abstract

High-grade serous ovarian cancer (HGSOC) is characterised by TP53 mutation and chromosome instability (CIN). The current standard of care includes cytoreductive surgery and cisplatin/taxane-based chemotherapy. However, many patients develop recurrent disease, and survival rates for HGSOC have not changed substantially for 20 years. To provide models for delineating CIN mechanisms and exploring novel therapeutics, we describe a workflow for generating ex vivocultures with extensive proliferative potential.

Method

15 models from the “living biobank” were validated by p53 profiling, exome sequencing and global transcriptomics, and karyotyped using single-cell whole genome sequencing. The models were transduced with a GFP-tagged histone and time-lapse microscopy was used to observe mitotic events and perform cell fate profiling. Drug sensitivity profiling of the models was performed by measuring green nuclear count to determine cell proliferation. This was also performed using time-lapse microscopy, as it provided a data-rich approach unlike many of the traditional end-point drug sensitivity assays.

Results

Time-lapse microscopy revealed catastrophic and highly heterogeneous mitoses, indicating that analysis of established cell lines grossly underestimates mitotic dysfunction in advanced human tumours. Drug profiling revealed a range of cisplatin sensitivities that were consistent with patient responses. There was extensive heterogeneity in cell fate profiles of the ex vivo models, indicating that genomic instability and mitotic dysfunction has an effect on culture dynamics.

Conclusion

Analysis of ex vivo cultures from the living biobank revealed the high genomic complexity of HGSOC, with profound mitotic heterogeneity that contributes to rampant CIN. By complementing cancer genomics and clinical data, this workflow has the potential to facilitate personalized approaches to treat HGSOC.