Details

Autor(en) / Beteiligte

• Li, Ming
• Hu, Shi-lian
• Shen, Zuo-jun
• He, Xiao-dong
• Tao, Shao-neng
• Dong, Lin
• Zhu, Yuan-yuan

Titel

High-performance capillary electrophoretic method for the quantification of global DNA methylation: Application to methotrexate-resistant cells

Ist Teil von

• Analytical biochemistry, 2009-04, Vol.387 (1), p.71-75

Ort / Verlag

United States: Elsevier Inc

Erscheinungsjahr

2009

Quelle

MEDLINE

Beschreibungen/Notizen

• Global DNA hypomethylation in tumor tissue is a common characteristic in a variety of malignancies such as breast, colon, oral, lung, and blood cancers. A rapid and sensitive method has been developed for the determination of global DNA methylation in cells. Five substances—2′-deoxycytidine (dC), 5-methyl 2′-deoxycytidine (mdC), 2′-deoxyadenosine (dA), 2′-deoxythymidine (dT), and 2′-deoxyguanosine (dG)—were completely separated by high-performance capillary electrophoresis in 10 min. Intraday coefficient of variation was less than 1%, and interday coefficient of variation was less than 2%. The minimal detection limit was 1 μM. Acquired drug resistance to methotrexate (MTX) is one of the most serious problems in cancer chemotherapy. Under optimal conditions, we analyzed global DNA methylation levels in A549 and A549/MTX cells, and only 10 5 cells are needed to obtain reliable results. The percentage of 5-methyl-2′-deoxycytidine (5-mC) was 4.80 ± 0.52% in A549 cells, and this decreased to 4.20 ± 0.44% in A549/MTX cells. It was considered as statistically significant. This demonstrated that the mechanisms of acquired drug resistance to MTX might be concerned with DNA methylation.