Amplification of RecQL4 genomic locus analyzed by mBAND-FISH and quantitative real time PCR.

<p>(A) Analysis of chromosome specific mBAND-FISH in the metaphase spreads of normal primary (HMEC), immortalized (MCF-10F) and tumorigenic breast cancer cell lines. Chromosomes and chromosome regions positive for the probe are shown in the inserts. (B) FISH analysis using spectrum orange labeled BAC (Bacterial Artificial Chromosome) probe proximal to 8q24.3 chromosome locus harboring the RecQL4 gene in MDA-MB453 and MDA-MB361 cells. The BAC probe was purchased from Open Biosystems (RP11–374B7, Huntsville, Alabama, USA). (C) Upper panel: Agarose gel electrophoresis showing the abundance of RecQL4 genomic DNA detected by PCR in breast cancer cell lines relative to normal primary and immortalized breast epithelial cells. GAPDH was used as an internal control; Lower panel: Abundance of RecQL4 genomic DNA detected by quantitative real time PCR in breast cancer cell lines relative to normal primary and immortalized breast epithelial cells. GAPDH was used for normalizing the values of RecQL4.