ES-2 Ovarian Cancer Cells Present a Genomic Profile Inconsistent with their Reported History

Objective: ES-2 ovarian cancer cells have long been reported to have originated from a primary clear cell carcinoma of the ovary presenting in a 47 year-old African American patient. Two recent publications have offered evidence calling both of these characteristics into question. Our objective was to further study this cell line using quantitative real-time PCR (qPCR) and mitochondrial DNA (mtDNA) sequencing in order to confirm or refute these inconsistencies.Results: qPCR assays on two characteristic loci, hepatocyte nuclear factor 1β (NHF-1β) and glutathione peroxidase 3 (GPX3), suggest that ES-2 are unusual clear cell carcinoma cells that appear more like high grade serous carcinoma than clear cell. Further, mtDNA haplotyping places the ancestral origin of the patient’s lineage in the Middle East or Europe and not Africa. These results are consistent with and support the conclusions of the two recent publications.