Endogenous Gene and Protein Expression of Drug Transporting Proteins in Cell Lines Routinely used in Drug Discovery Programs
2009 (English)In: Drug Metabolism And Disposition, ISSN 0090-9556, E-ISSN 1521-009X, Vol. 37, no 12, 2275-2283 p.Article in journal (Refereed) Published
The aim of this study was to investigate the gene and protein expression profiles of important drug transporting proteins in human cell lines commonly used for studies of drug transport mechanisms. Human cell lines used to transiently or stably express single transporters (HeLa, HEK293) and leukaemia cell lines used to study drug resistance by ABC-transporters (HL-60, K562) were investigated, and compared with organotypic cell lines (HepG2, Saos-2, Caco-2 and Caco-2 TC7). For gene expression studies, real-time PCR was used, while monospecific polyclonal antibodies were generated and used to investigate protein expression by immunohistochemistry. Thirty-six transporters were studied for gene expression and nine for protein expression. The antibodies were validated using expression patterns in human tissues. Finally, the function of one ubiquitously expressed transporter, MCT1; SLC16A1 was investigated using 14C-lactic acid as a substrate. In general, the adherent cell lines (HeLa, HEK293) displayed low transporter expression and the expression patterns were barely affected by transfection. The leukaemia cell lines (K562, HL-60) and Saos-2 also had low endogenous transporter expression, while the organotypic cell lines (HepG2 and Caco-2) showed higher expression of some transporters. Comparison of gene and protein expression profiles gave poor correlations, but better agreement was obtained for antibodies with a good validation score, indicating that antibody quality was a significant variable. Importantly, the monocarboxylic acid transporting protein MCT1 was significantly expressed in all, and functional in most of the cell lines, indicating that MCT1 may be a confounding factor when the transport of small anionic drugs is investigated.
Place, publisher, year, edition, pages
2009. Vol. 37, no 12, 2275-2283 p.
Cell lines, Caco-2, HEK293, HeLa, Saos-2, HL-60, K562, HepG2, Gene expression, Protein expression, MCT1
Research subject Biopharmaceutics; Pharmaceutics
IdentifiersURN: urn:nbn:se:uu:diva-107571DOI: 10.1124/dmd.109.028654ISI: 000271935200002PubMedID: 19741037OAI: oai:DiVA.org:uu-107571DiVA: diva2:231770