--- res: bibo_abstract: - "Background/Aim: Cancer cell lines are indispensible surrogate models in cancer research, as they can be used off-the-shelf, expanded to the desired extent, easily modified and exchanged between research groups for affirmation, reproduction or follow-up experiments.\r\nAs malignant cells are prone to genomic instability, phenotypical changes may occur after certain passages in culture. Thus, cell lines have to be regularly authenticated to ensure data quality. In between experiments these cell lines are often stored in liquid nitrogen for extended time periods.\r\nAlthough freezing of cells is a necessary evil, little research is performed on how long-term storage affects cancer cell lines. Therefore, this study investigated the effects of a 28-year long liquid nitrogen storage period on BT474 cells with regard to phenotypical changes, differences in cell-surface receptor expression as well as cytokine and gene expressional variations.\r\nMethods: Two batches of BT474 cells, one frozen in 1986, the other directly purchased from ATCC were investigated by light microscopy, cell growth analysis, flow cytometry and cytokine as well as whole-transcriptome expression profiling.\r\nResults: The cell lines were morphologically indifferent and showed similar growth rates and similar cell-surface receptor expression. Transcriptome analysis revealed significant differences in only 26 of 40,716 investigated RefSeq transcripts with 4 of them being up-regulated and 22 down-regulated.\r\nConclusion: This study demonstrates that even after very long periods of storage in liquid nitrogen, cancer cell lines display only minimal changes in their gene expression profiles. However, also such minor changes should be carefully assessed before continuation of experiments, especially if phenotypic alterations can be additionally observed.@eng" bibo_authorlist: - foaf_Person: foaf_givenName: Judit foaf_name: Fazekas, Judit foaf_surname: Fazekas foaf_workInfoHomepage: http://www.librecat.org/personId=36432834-F248-11E8-B48F-1D18A9856A87 orcid: 0000-0002-8777-3502 - foaf_Person: foaf_givenName: Thomas W. foaf_name: Grunt, Thomas W. foaf_surname: Grunt - foaf_Person: foaf_givenName: Erika foaf_name: Jensen-Jarolim, Erika foaf_surname: Jensen-Jarolim - foaf_Person: foaf_givenName: Josef foaf_name: Singer, Josef foaf_surname: Singer bibo_doi: 10.18632/oncotarget.16623 bibo_volume: 8 dct_date: 2017^xs_gYear dct_isPartOf: - http://id.crossref.org/issn/1949-2553 dct_language: eng dct_publisher: Impact Journals@ dct_title: Long term storage in liquid nitrogen leads to only minor phenotypic and gene expression changes in the mammary carcinoma model cell line BT474@ ...