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BackgroundProstate cancer (CaP) is one of the most relevant causes of cancer death in Western Countries. Although detection of CaP at early curable stage is highly desirable, actual screening methods present limitations and new molecular approaches are needed. Gene expression analysis increases our knowledge about the biology of CaP and may render novel molecular tools, but the identification of accurate biomarkers for reliable molecular diagnosis is a real challenge. We describe here the diagnostic power of a novel 8-genes signature: ornithine decarboxylase (ODC), ornithine decarboxylase antizyme (OAZ), adenosylmethionine decarboxylase (AdoMetDC), spermidine/spermine N(1)-acetyltransferase (SSAT), histone H3 (H3), growth arrest specific gene (GAS1), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and Clusterin (CLU) in tumour detection/classification of human CaP.Methodology/principal findingsThe 8-gene signature was detected by retrotranscription real-time quantitative PCR (RT-qPCR) in frozen prostate surgical specimens obtained from 41 patients diagnosed with CaP and recommended to undergo radical prostatectomy (RP). No therapy was given to patients at any time before RP. The bio-bank used for the study consisted of 66 specimens: 44 were benign-CaP paired from the same patient. Thirty-five were classified as benign and 31 as CaP after final pathological examination. Only molecular data were used for classification of specimens. The Nearest Neighbour (NN) classifier was used in order to discriminate CaP from benign tissue. Validation of final results was obtained with 10-fold cross-validation procedure. CaP versus benign specimens were discriminated with (80+/-5)% accuracy, (81+/-6)% sensitivity and (78+/-7)% specificity. The method also correctly classified 71% of patients with Gleason score or =7, an important predictor of final outcome.Conclusions/significanceThe method showed high sensitivity in a collection of specimens in which a significant portion of the total (13/31, equal to 42%) was considered CaP on the basis of having less than 15% of cancer cells. This result supports the notion of the "cancer field effect", in which transformed cells extend beyond morphologically evident tumour. The molecular diagnosis method here described is objective and less subjected to human error. Although further confirmations are needed, this method poses the potential to enhance conventional diagnosis.

Androgen effects on lipoproteins, mainly high density lipoprotein (HDL), could be exerted by a direct interaction of testosterone (T) or dihydrotestosterone (DHT) with liver androgen receptors. To assess if T needs to be converted into DHT to affect lipid metabolism, 13 patients were studied, affected with benign prostatic hyperplasia (BPH) and treated with an inhibitor of 5 alpha-reductase (finasteride). They were compared with 15 untreated controls. At baseline and after 3 and 6 months of therapy, each patient was evaluated as for lipoprotein and hormone concentrations, as well as for nutritional status. Body composition was assessed by anthropometry and bio-impedance analysis (BIA). Treatment was associated with a significant increase of HDL-cholesterol (HDL-C), mainly HDL3 subclass, and lipoprotein(a) (Lp(a)), as well as a decline of DHT, whereas no significant changes were apparent for T, estradiol (E2), sex hormone binding hormone (SHBG) and body composition indexes. However, no significant associations between DHT and lipid relative changes were apparent at bivariate correlation analysis. This finding was confirmed by comparing patient subsets identified by cluster analysis, according to HDL subclass individual responses. Rather, a slight association with E2 for HDL2 (positive) and HDL3 (negative) was found. In conclusion, finasteride can modify HDL and Lp(a) concentrations. However, by the data, these effects cannot be definitively attributed to the changes in DHT synthesis induced by finasteride, since a direct and non-specific interference of the drug on liver metabolism cannot be excluded.