Figure 2. Northern blot analysis using probes for DD3, now called PCA3 (upper lane) and PSA (middle lane), with rRNA (28S) as a control (lower lane). Ten µg of total RNA were loaded per lane. Numbers 1-14 refer to different patients whose mRNA was studied in the analysis. Tissues studied: T=tumor, B=benign prostatic hyperplasia, N=normal, N/T=normal+10% tumor cells, and M=metastasis. Over-expression is determined by comparing the intensity of the bands. Note that PSA mRNA does not distinguish normal from tumor tissues, whereas DD3 (PCA3) is clearly over expressed in tumors. Reproduced from M.J. Bussemakers, et al, Cancer Res. 59: 5975, 19994 (with permission).