High-grade serous ovarian cancer (HGS-OVCA) is the most common type of ovarian cancer. HGS-OVCA genomes are usually very complex and unstable. Many studies have addressed cytogenetic changes, and with the advent of high-throughput sequencing, complex chromosomal rearrangements. However, little is known about how gene fusions, potentially causing aberrant transcripts and protein products drive tumorigenesis, cell growth and/or metastasis in HGS-OVCA. Patients with the same histological or morphological phenotype of cancer have tumors with diverse genetic backgrounds or molecular phenotypes. There is thus an urgent need to better stratify patients and their tumors and to understand the chemotherapy and other treatment responses at the molecular level.

The purpose of this study is to find and charaterize novel recurrent chromosomal rearrangements from HGS-OVCA patient samples. We aim to identify rearrangement hotspots from genomic data. However, not only do we need to identify, characterize and stratify the genomic alterations, but also to find those changes with potentially tumorigenic functions at the RNA and protein levels.

We utilise datasets of The Cancer Genome Atlas (https://cancergenome.nih.gov/) and HERCULES Project (http://www.project-hercules.eu/) to identify rearrangement-prone chromosomal regions (putative “breakpoint hotspots”) and complex structural aberrations and variations. We concentrate on exonic aberrations seen in both datasets in at least 2 patients. The findings will be validated using two HGS-OVCA fresh-frozen tumor sample collections from Helsinki and Turku University Hospitals. Clinical data and homologous recombination (HR) score of the tumor samples (HR proficient or HR deficient; Tumiati et al. 2018) will also be analyzed.

Preliminary results of this work will be presented. We believe that combining sequencing and clinical data with state-of-the-art molecular level analyses and functional tests will deepen our understanding of HGS-OVCA biology and help to develop new anti-cancer treatment options for this “silent killer”.

Citation Format: Nanna Sarvilinna, Barun Pradhan, Imrul Faisal, Manuela Tumiati, Amjad Alkodsi, Liisa Kauppi. IDENTIFICATION OF NOVEL CHROMOSOMAL REARRANGEMENTS IN HIGH-GRADE SEROUS OVARIAN CANCER [abstract]. In: Proceedings of the 12th Biennial Ovarian Cancer Research Symposium; Sep 13-15, 2018; Seattle, WA. Philadelphia (PA): AACR; Clin Cancer Res 2019;25(22 Suppl):Abstract nr GMM-050.

©2019 American Association for Cancer Research.
2019
American Association for Cancer Research.