A2780

A2780 (platinum-sensitive) and A2780cis (platinum resistance) human ovarian cancer cell lines were purchased from Sigma Aldrich (Gillingham, UK). PEO1 (BRCA2 deficient) and PEO4 (BRCA2 proficient) were purchased from American Type Culture Collection (ATCC, Manassas, VA, USA). A2780, A2780cis, PEO1, and PEO4 were cultured in RPMI (R8758, Merck, Dorset, UK) with 10% FBS (F4135, Merck, Dorset, UK), 1% Penicillin-Streptomycin (P4333, Merck, Dorset, UK). FEN1-deficient HeLa SilenciX cells and control HeLa cells were purchased from Tebu-Bio and were grown in Dulbecco’s Modified Eagle’s Medium (11965092, Thermo Fisher Scientific) supplemented with 10% FBS, 1% penicillin/streptomycin, and 125 μg/mL hygromycin B. All cell lines were maintained in a humidified incubator at 37 °C in a 5% CO₂ atmosphere.

The human OC cell lines, A2780 and A2780cis were obtained from Sigma Aldrich. The latter made resistant to cisplatin as previously described [48 (link)]. The ES-2 (CRL-1978) and SK-OV-3 (HTB-77) cells were both purchased from American Type Culture Collection (ATCC, Wesel, Germany). The cells were cultured in RPMI 1640 (A2780 and A2780cis) or McCoys 5A medium (ES-2 and SK-OV-3) and complemented with 10% FCS and 2% pest/glut (all Sigma Aldrich). The human OC cell line SK-OV-3-Luc IP1 is a more potent, luciferase positive OC cell line, created through in vivo selection [49 (link)]. Sort Tandem Repeat (SRT) profiling was conducted as described by De Vlieghere et al. [49 (link)]. This cell line was cultured in Dulbecco's Modified Eagle's Medium (DMEM, Life technologies, ThermoFisher, Ghent, Belgium), supplemented with 2% penicillin/streptomycin (Life technologies) + 0.005% fungizone (Bristol-Myers-Squib B.V., Utrecht, The Netherlands) and 10% FCS (Sigma-Aldrich) [50 (link)]. Saline and BD matrigel (Life Sciences, Antwerp, Belgium) were used to dilute SK-OV-3-Luc IP1 cells before IP and SP injection, respectively. The cell banks performed authentications by short tandem repeat analysis. All cell line experiments in Sweden were performed within 6 month after resuscitation, in Belgium STR was done to verify identity.

The human cancer cell lines Jurkat (acute T-cell leukemia, ATCC, Manassas, VA), A2780 (ovarian carcinoma, Sigma Aldrich, St. Louis, MO, US), HeLa (cervical carcinoma, ATCC), U2OS (osteosarcoma, ATCC), Hep3B (hepatoma, ATCC), and LN229 (glioblastoma, ATCC) were used during this study. Jurkat and A2780 cells were grown in RPMI-1640 (Sigma Aldrich), HeLa, Hep3B, and LN229 cells were cultured in Dulbecco’s modified eagle medium (DMEM, Sigma Aldrich). All growth media were supplemented with 10% heat-inactivated fetal bovine serum (FCS, PAA, Biowest, Nuaillé, France). Cells were passaged twice a week and regularly tested on Mycoplasma contamination (Mycoplasma kit, Sigma Aldrich). Cells were kept in 37 °C humid incubators containing 5% CO₂ and 10% O₂. For indicated experiments, the O₂ level was reduced to 0–0.5%, creating a hypoxic environment.