Figure 2.

Southern blot analyses of mouse and human cell lines hybridized with murine and human cyclin D2 cDNA probes, as indicated (upper panels). Mouse lines: WEHI 231 B-cell lymphoma (low Myc) and MOPC 460D plasmacytoma (high Myc); Human lines: GL30/92T primary fibroblasts (low Myc), T47D breast carcinoma cells (high Myc), and COLO320HSR colorectal carcinoma cells (very high Myc). Digests were carried out with the enzymes indicated. 10 µg of DNA were loaded per lane. The filters were rehybridized with the cDNA of mouse R1 (lower panels) to control for amount of DNA loaded. More DNA from GL30/92T was loaded in the control wells to illustrate the restriction endonuclease products of the unamplified cyclin D2 gene. Filled arrowheads point to amplified cyclin D2 bands; empty arrowheads indicate lost bands that suggest another form of genomic instability in this tumor.