Improvement of prostate cancer detection by integrating the PSA test with miRNA expression profiling

Abstract

Prostate-specific antigen (PSA) test is limited in prostate cancer diagnosis due to its inaccuracy. A new approach which integrates the PSA test with miRNA profiling was investigated to improve prostate cancer diagnosis. Six prostate cancer-related miRNAs (miR-16, -21, -34c, -101, -125b, -141) were tested in five cultured prostate cell lines and 20 human prostate specimens. We found that the miRNA expression profiles were significantly different between nontumorigenic and tumorigenic cell lines and specimens. Positive predictive value analysis of prostate cancer was increased from 40% to 87.5% by integrating patient PSA blood levels with miR-21 and miR-141 profiles.

Figure 1

Western blot of protein expression of Bcl-2, COX-2, and p53 in benign prostatic hyperplasia BPH1 cell line, tumorigenic BPH1CAFTD, androgen receptor positive prostate tumorigenic LNCap cell line, androgen receptor negative prostate tumorigenic PC3 cell line, and in nontumorigenic human prostatic PNT1 cell line. (A). The relative intensity was measured by using Bio-Rad Quantity one software; the bar shows the fold change of protein levels compared to that in PNT1 (B).

Figure 2

PCNA expression in BPH1CAFTD and BPH1 cells and their corresponding xenograft tumors. The levels of PCNA expression were detected by Western blot in cultured cell lines, and relative intensity was measured by using Bio-Rad Quantity one software (A). Immunohistochemical staining was used to measure PCNA expression in xenograft tumors. The number of PCNA positive cells was counted per 100 cells, 200 × (B).