title: Identification and characterization of different subpopulations in a human lung adenocarcinoma cell line (A549).
abstract: The morphology, cell growth, antigenic expression and tumorigenicity of cell subpopulations from the A549 lung adenocarcinoma isolated by Percoll gradient separation have been analysed. Four subpopulations were obtained (subpopulations A, B, C and D). Immunocytochemical analysis of several antigens was performed with monoclonal antibodies (MAbs): MUC1 mucin (C595, HMFG1 and HMFG2), MUC5B (PANH2); gp230 (PANH4); carbohydrate antigens including sialyl Lewis x (KM93), Tn antigen (83D4), Lewis y (C14); 5, 6, 8, 17 and 19 cytokeratins and p53. The cell population D tended to form cell aggregates that piled up on the monolayer similar to overgrowth cultures of the A549 parental cell line, whereas A, B and C cell subpopulations formed well spread monolayers. Both parental A549 and subpopulation D secreted abundant mucus. The topographic distribution and secretion production were correlated with tumorigenic assays since only subpopulation D grew in nude mice exhibiting reduced latency period; these characteristics correlated with the fast growth of the subpopulation D in vitro. Immunocytochemical analysis demonstrated that subpopulation D showed greater expression of MUC1 mucin and carbohydrate antigens such as Tn antigen, sialyl Lewis x and Lewis y and less expression of cytokeratins, p53, MUC5B and gp230; conversely, subpopulations A, B and C showed the opposite antigenic profile. Our results illustrate heterogeneity in the A549 cell line; subpopulations A, B and C retained characteristics of more differentiated adenocarcinoma while subpopulation D displayed features of a less differentiated tumor line.
authors.affiliation: Universidad Nacional de la Plata, Centro de Investigaciones Inmunológicas Básicas y Aplicadas (CINIBA) Calle 60 y 120, La Plata, Argentina.
authors.forename: M V
authors.initials: MV
authors.lastname: Croce
authors.forename: A G
authors.initials: AG
authors.lastname: Colussi
authors.forename: M R
authors.initials: MR
authors.lastname: Price
authors.forename: A
authors.initials: A
authors.lastname: Segal-Eiras
mesh_terms: D000230:Adenocarcinoma / Q000276:immunology / Q000473:pathology*; D000818:Animals; D000911:Antibodies, Monoclonal; D002469:Cell Separation; D006801:Humans; D007150:Immunohistochemistry; D007633:Keratins / Q000032:analysis; D008175:Lung Neoplasms / Q000276:immunology / Q000473:pathology*; D051379:Mice; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009844:Oligosaccharides / Q000032:analysis; D010641:Phenotype; D000080506:Sialyl Lewis X Antigen; D013997:Time Factors; D014407:Tumor Cells, Cultured; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
chemical_list: D000911:Antibodies, Monoclonal; D009844:Oligosaccharides; D000080506:Sialyl Lewis X Antigen; D016159:Tumor Suppressor Protein p53; D007633:Keratins