کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2111296 1083973 2009 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Amplification of the ABCB1 region accompanied by a short sequence of 200bp from chromosome 2 in lung cancer cells
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی تحقیقات سرطان
پیش نمایش صفحه اول مقاله
Amplification of the ABCB1 region accompanied by a short sequence of 200bp from chromosome 2 in lung cancer cells
چکیده انگلیسی

Lung cancer sublines No15-80-1 and No15-80-6 were selected by treatment of cell line NCI-H460 with paclitaxel at stepwise increasing concentrations from 50 nmol/L to 800 nmol/L. The two sublines exhibited amplifications of the ABCB1 region (previously MDR1) with different copy number profiles, but shared a common amplification pattern, which has been observed in amplification mediated by the breakage-fusion-bridge (BFB) cycle. Sequence analysis of the distal ends of the amplified regions, which were probably generated in a break-and-fusion of the initial round of the BFB cycle, revealed a head-to-head fused sequence of chromosome 7. The sequence was identical in the two sublines. A short sequence of 200 bp derived from chromosome 2 was incorporated, suggesting translocation between chromosomes 2 and 7. The copy number of the short sequence was comparable to that of the neighboring sequence, suggesting coamplification. The timing of the occurrence of the putative translocation and the initiation of BFB-cycle-driven amplification during the stepwise selection were determined by using the unique junction sequences specific to these events as indicators. The results demonstrated that the translocation occurred at the step of 100 nmol/L treatment and the BFB cycle initiated in the step of 400 nmol/L-treatment. It is likely that the translocation, preceding amplification by several selection steps, activated ABCB1 gene expression. The diversity in amplification profiles between the two sublines was generated by the separately operating BFB cycles, after an initial break-and-fusion that probably occurred in a single cell.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cancer Genetics and Cytogenetics - Volume 194, Issue 1, 1 October 2009, Pages 4–11
نویسندگان
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