Methylation status of breast cancer resistance protein detected by methylation‐specific polymerase chain reaction analysis is correlated inversely with its expression in drug‐resistant lung cancer cells

Nakano, Hirofumi; Nakamura, Yoichi; Soda, Hiroshi; Kamikatahira, Megumi; Uchida, Koki; Takasu, Mineyo; Kitazaki, Takeshi; Yamaguchi, Hiroyuki; Nakatomi, Katsumi; Yanagihara, Katsunori; Kohno, Shigeru; Tsukamoto, Kazuhiro

doi:10.1002/cncr.23285

Cited by 28 publications

(30 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…These results are corresponding to the evidence reported previously [30,31]. Current study suggested that over-expression of BCRP in human cancer cell lines resulted in cell resistance to a variety of chemotherapeutic agents, and the functional efflux-pump activity of BCRP almost corresponded to the level of BCRP protein expression [16]. Transfection studies from different laboratories have confirmed that the enforced expression of BCRP/ABCG2 cDNA in different cell types confers the resistance to a variety of chemotherapeutic agents and reduces drug accumulation in the cells [10].…”

Section: Discussionsupporting

confidence: 78%

“…Current evidence indicates that BCRP/ABCG2 transcription is regulated by hypoxia [13] or estrogen response elements located in the promoter region of the BCRP gene [14,15]. It is also regulated by the methylation of the promoter region of the BCRP/ABCG2 gene [16][17][18]. There is much evidence indicating that hypermethylation of tumors is related to DNA methyltransferases (DNMTs).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Developing multidrug-resistant cells and exploring correlation between BCRP/ABCG2 over-expression and DNA methyltransferase

Ji¹,

Yuan²,

Liu³

et al. 2010

ABBS

View full text Add to dashboard Cite

Expression of breast cancer resistance protein/ATP-binding cassette sub-family G member 2 (BCRP/ABCG2) is the major cause of chemotherapy failure. It is important to establish and characterize the multidrug resistance cells and to investigate the mechanism of multidrug resistance. Multidrug-resistant cells expressing BCRP/ABCG2 based on human breast cancer MCF-7/wt cells were developed by gradually increasing application of low concentration of mitoxantrone. Real-time quantitative PCR, western blot, and immunofluorescence assay were employed to analyze BCRP mRNA and protein expression. Drug accumulation in the cells was measured by flow cytometry and DNA methyltransferases were analyzed by western blot. The results indicated that the inhibitory ratio of cell proliferative growth exhibited an exponential relation with the concentration of mitoxantrone. The IC 50 of MCF-7/wt cells to mitoxantrone was found to be 0.42 mM. 3-(4,5-Dimethylthlthiazol-2-YI)-2,5-Diphenyltetrazolium Bromide assay indicated that the mitoxantrone-resistant cells at different stages exhibited cross-resistance to adriamycin and taxol. BCRP/ABCG2 mRNA and protein levels in the mitoxantrone-resistant cells at different stages increased with increasing concentration of mitoxantrone. Intracellular accumulation of mitoxantrone in the cells decreased with the increase of the BCRP/ABCG2 expression levels. DNA methyltransferase 1 (DNMT1) and DNA methyltransferase 3a (DNMT3a) expressions in the cells at different stages decreased slightly, whereas DNA methyltransferase 3b (DNMT3b) expression decreases significantly. BCRP/ABCG2 overexpression and its drug-efflux function in the drug-resistant cells are the main factors to produce multidrug resistance. Our results suggest that multidrug resistance is related to overexpression of BCRP/ ABCG2 and the decrease of DNA methyltransferases, especially DNMT3b.

show abstract

Section: Discussionsupporting

confidence: 78%

Section: Introductionmentioning

confidence: 99%

Developing multidrug-resistant cells and exploring correlation between BCRP/ABCG2 over-expression and DNA methyltransferase

Ji¹,

Yuan²,

Liu³

et al. 2010

ABBS

View full text Add to dashboard Cite

show abstract

“…It has been shown that CpG methylation of the ABCG2 promoter could result in its transcriptional silencing (25). Therefore, we sought to determine whether afatinib could affect the methylation status of the ABCG2 promoter, which lead to a reduction in ABCG2 mRNA level.…”

Section: Downregulation Of Abcg2 By Afatinib Was Independent Of Protementioning

confidence: 99%

Afatinib Enhances the Efficacy of Conventional Chemotherapeutic Agents by Eradicating Cancer Stem–like Cells

Wang

et al. 2014

Cancer Research

View full text Add to dashboard Cite

Cancer stem cells (CSC) have garnered significant attention as a therapeutic focus, based on evidence that they may represent an etiologic root of treatment-resistant cells. Indeed, expression of the multidrug resistance protein ATP-binding cassette subfamily G member 2 (ABCG2) confers chemoresistance to CSCs, where it serves as a potential biomarker and therapeutic target. Here, we show that afatinib, a small-molecule inhibitor of the tyrosine kinases EGFR, HER2, and HER4, preferentially eliminated side population cells with CSC character, in both cell lines and patient-derived leukemia cells, by decreasing ABCG2 expression. In these cells, afatinib also acted in parallel to suppress self-renewal capacity and tumorigenicity. Combining afatinib with the DNA-damaging drug topotecan enhanced the antitumor effect of topotecan in vitro and in vivo. Mechanistic investigations suggested that ABCG2 suppression by afatinib did not proceed by proteolysis through the ubiquitin-dependent proteosome, lysosome, or calpain. Instead, we found that afatinib increased DNA methyltransferase activity, thereby leading to methylation of the ABCG2 promoter and to a decrease in ABCG2 message level. Taken together, our results advocate the use of afatinib in combination with conventional chemotherapeutic drugs to improve efficacy by improving CSC eradication. Cancer Res; 74(16); 4431-45. Ó2014 AACR.

show abstract

“…In particular, gene amplification (Ross et al, 1999;Knutsen et al, 2000;Volk et al, 2002) has been shown to be an important mechanism for elevated ABCG2 expression in drug-resistant cancer cells. Recent studies have demonstrated that transcriptional factors [i.e., nuclear receptors (Ee et al, 2004b;Ebert et al, 2005;Szatmari et al, 2006;Honorat et al, 2008;Narang et al, 2008;Vore and Leggas, 2008;Wang et al, 2008b) and epigenetic factors Turner et al, 2006;Calcagno et al, 2008;Nakano et al, 2008;To et al, 2008a)] play important roles in the regulation of ABCG2 in different model systems. Potential regulation of ABCG2 at its 3Ј-untranslated region (3Ј-UTR) is just beginning to be explored .…”

mentioning

confidence: 99%

MicroRNA-328 Negatively Regulates the Expression of Breast Cancer Resistance Protein (BCRP/ABCG2) in Human Cancer Cells

2009

View full text Add to dashboard Cite

Breast cancer resistance protein (BCRP/ABCG2) is a molecular determinant of pharmacokinetic properties of many drugs in humans. To understand post-transcriptional regulation of ABCG2 and the role of microRNAs (miRNAs) in drug disposition, we found that microRNA-328 (miR-328) might readily target the 3Ј-untranslated region (3Ј-UTR) of ABCG2 when considering target-site accessibility. We then noted 1) an inverse relation between the levels of miR-328 and ABCG2 in MCF-7 and MCF-7/MX100 breast cancer cells and 2) that miR-328 levels could be rescued in MCF-7/MX100 cells by transfection with miR-328 plasmid. Luciferase reporter assays showed that ABCG2 3Ј-UTR-luciferase activity was decreased more than 50% in MCF-7/MX100 cells after transfection with miR-328 plasmid, the activity was increased over 100% in MCF-7 cells transfected with a miR-328 antagomir, and disruption of miR-328 response element within ABCG2 3Ј-UTR led to a 3-fold increase in luciferase activity. Furthermore, the level of ABCG2 protein was down-regulated when miR-328 was over-expressed, and the level was up-regulated when miR-328 was inhibited by selective antagomir. Altered ABCG2 protein expression was associated with significantly declined or elevated levels of ABCG2 3Ј-UTR and coding sequence mRNAs, suggesting possible involvement of the mechanism of mRNA cleavage. Finally, miR-328-directed down-regulation of ABCG2 expression in MCF-7/MX100 cells resulted in an increased mitoxantrone sensitivity, as manifested by a significantly lower IC 50 value (2.46 Ϯ 1.64 M) compared with the control (151 Ϯ 32 M). Together, these findings suggest that miR-328 targets ABCG2 3Ј-UTR and, consequently, controls ABCG2 protein expression and influences drug disposition in human breast cancer cells.Breast cancer resistance protein BCRP/ABCG2 is an ATPbinding cassette membrane transporter expressed ubiquitously in humans, controlling the absorption, distribution and clearance of numerous xenobiotics, including pharmaceutical agents, dietary carcinogens and conjugated metabolites (Mao and Unadkat, 2005;van Herwaarden and Schinkel, 2006;Vore and Leggas, 2008). In addition, overexpression of ABCG2 and other drug transporters in tumorigenic stem cells represents an important mechanism for multidrug resistance (Dean et al., 2005). Because ABCG2 was discovered in drugresistant human cancer cells (e.g., MCF-7/AdrVp and S1MI80), these cell lines have been widely used for studying the function and regulation of ABCG2 and defining its role in drug disposition and multidrug resistance. In particular, gene amplification (Ross et al., 1999;Knutsen et al., 2000;Volk et al., 2002) has been shown to be an important mechanism for elevated ABCG2 expression in drug-resistant cancer cells. Recent studies have demonstrated that transcriptional factors [i.e., nuclear receptors (Ee et al.,

show abstract

Methylation status of breast cancer resistance protein detected by methylation‐specific polymerase chain reaction analysis is correlated inversely with its expression in drug‐resistant lung cancer cells

Cited by 28 publications

References 44 publications

Developing multidrug-resistant cells and exploring correlation between BCRP/ABCG2 over-expression and DNA methyltransferase

Developing multidrug-resistant cells and exploring correlation between BCRP/ABCG2 over-expression and DNA methyltransferase

Afatinib Enhances the Efficacy of Conventional Chemotherapeutic Agents by Eradicating Cancer Stem–like Cells

MicroRNA-328 Negatively Regulates the Expression of Breast Cancer Resistance Protein (BCRP/ABCG2) in Human Cancer Cells

Contact Info

Product

Resources

About