caa a22 4500 606236619 CHVBK 20210128101248.0 cr unu---uuuuu 210128e20150201xx s 000 0 eng 10.1007/s11010-014-2260-7 doi (NATIONALLICENCE)springer-10.1007/s11010-014-2260-7 OCT4 mutations in human erythroleukemic cells: implications for multiple drug resistance (MDR) phenotype [Elektronische Daten] [Bruno Oliveira, Marcio Figueiredo, Gilma Trindade, Luis Marins] The OCT4 transcription factor is a crucial stem cells marker and it has been related to the cancer stem cells concept. Moreover, it has also been associated to the multiple drug resistance (MDR) phenotype. Our first results pointed out a straight relation between OCT4 and ABC transporters in K562-derivative MDR (Lucena) cells. Sequencing of ABC promoters did not reveal any mutation that could explain the differential expression of OCT4 in Lucena cells. Furthermore, sequencing of the homeobox domain region from the OCT4 gene isolated from both cell lines evinced, for the first time, that this transcription factor is a target of mutations and might be related to the MDR phenotype. The encountered mutations implied in several amino acids substitutions in both cell lines. K562 had seven amino acids substituted (three of them exclusive), while Lucena had 13 substitutions (nine of them exclusive). In addition, an in silico search for phosphorylation motifs within the amino acid stretch compared showed that human normal OCT4 has seven potential phosphorylation motifs. However, K562 has lost one phosphorylation motif and Lucena two of them. These findings bring OCT4 as an important target for cancer treatment, especially those resistant to chemotherapy. Springer Science+Business Media New York, 2014 K562 nationallicence K562-Lucena nationallicence Gene expression nationallicence ABC transporters nationallicence Transcription factors nationallicence Phosphorylation motifs nationallicence Oliveira Bruno Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut Figueiredo Marcio Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut Trindade Gilma Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut Marins Luis Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut Molecular and Cellular Biochemistry Springer US; http://www.springer-ny.com 400/1-2(2015-02-01), 41-50 0300-8177 400:1-2<41 2015 400 11010 https://doi.org/10.1007/s11010-014-2260-7 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11010-014-2260-7 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Oliveira Bruno Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut NATIONALLICENCE 700 1- Figueiredo Marcio Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut NATIONALLICENCE 700 1- Trindade Gilma Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut NATIONALLICENCE 700 1- Marins Luis Instituto de Ciências Biológicas (ICB), Universidade Federal do Rio Grande - FURG, Rio Grande. Av. Italia Km8, 96203-900, Rio Grande, RS, Brazil aut NATIONALLICENCE 773 0- Molecular and Cellular Biochemistry Springer US; http://www.springer-ny.com 400/1-2(2015-02-01), 41-50 0300-8177 400:1-2<41 2015 400 11010