RESUMO
Esophageal cancer exhibits an uneven geographical distribution strikingly, resulting in focal endemic high-incidence areas in several countries worldwide including China, which might be associated with the environmental and genetic risk factors in those areas. Permanent cancer cell lines are invaluable tools in understanding the biology of cancers and experimental therapeutics. To enrich cell line panel and animal models of human esophageal squamous cell carcinoma (ESCC) from different geographical areas and investigate the environmental and genetic risk factors in the carcinogenesis of ESCC, a novel human esophageal squamous cancer cell line (ESC-410) was established. The cell line grew adherent as a monolayer and maintained stable growth rate with a doubling time of 53 h and distinct epithelial morphological appearance; it was maintained in vitro for 18 months and subcultured for more than 50 passages. Ultrastructural examination revealed large irregular nuclei, desmosome, and tonofilaments; karyotype analysis showed a modal number of chromosomes that ranged from 35 to 73, with a median of 57, and 77% of analyzed cells were hyperdiploidy; reverse transcription polymerase chain reaction (RT-PCR) detected the mRNA expressions of CK8, CK18, and CK19 in the established cells; immunofluorescence assay identified the protein expressions of neurotrophin receptor p75 and integrin α6 (CD49f) in the ESC-410 cell line; xenotransplantation of ESC-410 cells into athymic nude mice subcutaneously induced the formation of solid tumor masses in about 2 weeks. By histopathological examination, heterogeneity of xenograft tumor was observed, as same as that of human primary ESCC. All findings and evidence in this experimental study suggested that this cell line might be a useful model in vitro and in vivo in cellular and molecular studies as well as in testing novel therapies for human ESCC.
