This is hetero geneous in single ESCC or BAC cell lines, thereby reflecting the heterogeneity also observed in individual patients with ESCC or BAC. The study therefore represents a basis for further translational assessment of Aurora kinases and associated cell cycle control in aneu ploid ESCC and BAC cells, nevertheless particularly also in view of discussions of Aurora kinases as therapeutic targets. Further assessment of Aurora kinases and p53 interactions in cell lines or tissue specimens derived from precursor lesions of dysplasia or intest inal metaplasia are necessary to disclose a causative role of Aurora kinases and p53 in the develop ment of aneuploid, invasive esophageal cancers. Methods Cell culture The study included as control a normal esophageal epithelial cell line as well as four esophageal cancer cell lines.

The esophageal cancer cell lines were ori ginally derived from patients with esophageal squamous cell carcinomas, Barretts ade nocarcinoma or an esophageal junctional adenocarcinoma. Indeed, the specificity of the adenocarcinoma cell lines was recently approved. Due to clear adenocarcinoma differentiation and growth patterns, the two cell lines OE33, OE19 are col lectively referred to as BAC in the present in vitro study, which does not address the carcinogenesis of eso phageal carcinomas in view of the intestinal metaplasia dysplasia carcinoma sequence. EPC hTERT cells were cultivated in Keratinocyte SFM medium supplemented with 40 ug ml bovine pituitary extract, 1. 0 ng ml EGF, 100 units ml penicillin and 100 ug ml streptomycin at 37 C in a 5% CO2 atmosphere.

The esophageal cancer cell lines OE21 and Kyse 410 and the BAC cell lines OE33 and OE19 were cultivated in RPMI 1640 medium, supplemented with 10% Fetal Bovine Serum and 2 mM GIBCO L Glutamin at 37 C in a 5% CO2 atmosphere. Hematoxylin and Eosin staining Cells grown on coverslips were fixed with 4% parafor maldehyde, rinsed with Phosphate buffered saline and stained with Hematoxylin. After removing the hema toxylin solution mains water was added twice. Cells were stained with Eosin Y solution and distilled water was added. The cov erslips were then immersed in an ascending ethanol series and in xylol. Cell cycle phase distribution analysis by flow cytometry For cell cycle distribution analyses by flow cytometry cells were grown to 50% 60% confluency.

The cells in the medium and trypsinized cells were collected and fixed in ice cold 70% ethanol. After washing with PBS cells were stained with propidium iodide, 0. 1% Tritron X 100, 0. 2 mg ml Ribonuclease A in PBS Stained cells were analyzed using the LSRII system and DB FACS Diva software. Fluorescence in situ hybridization Cells were grown on Poly L Lysine coated Lab Tek 1 Well Glass Slides. Cells were washed with PBS, fixed in 3,1 methanol glacial acetic acid and dehydrated in an ethanol series. AURKA 20q11 DNA probe or AURKB Alphasatellite 17 Cilengitide specific DNA probe was applied.