ODC1 has been identified as a genetic marker for colon cancer  and over-expression of ODC1 has been linked to high risk neuroblastomas  and colorectal and breast cancers . upon the Gleason grade. Majority (>80%) of the malignant tissue cores were graded 4+3 and 3+4. A comparison between these two Gleason grades did not show a significant difference for the expression of four biomarkers tested (Mann-Whitney test). Data is presented as means SEM for 75-109 individual tissue cores for each grade for the four biomarkers.(TIF) pone.0084295.s003.tif (84K) GUID:?C90A4B24-756C-4911-96C6-0EEFD5EB8246 Methods S1: (DOC) pone.0084295.s004.doc (23K) GUID:?560E09A0-6AF9-406B-96B3-2FC233F5BDDF Table S1: (PDF) pone.0084295.s005.pdf (292K) GUID:?B45A8469-7AF7-4747-86F5-818A32B6E8D4 Table S2: (PDF) pone.0084295.s006.pdf (214K) GUID:?CA28533E-8CEB-4F05-B408-56F35B5D00C5 Abstract Prostate carcinoma is the most common cancer in men with few, quantifiable, biomarkers. Prostate cancer biomarker discovery has been hampered due to subjective analysis of protein expression in tissue sections. An unbiased, quantitative immunohistochemical approach provided here, for the diagnosis and stratification of prostate cancer could overcome this problem. Antibodies against four proteins BTF3, HINT1, NDRG1 and ODC1 were used in a prostate tissue array (> 500 individual tissue cores from 82 patients, 41 case pairs matched with one patient in each pair had biochemical recurrence). Protein expression, quantified in an unbiased manner using an automated analysis protocol in ImageJ software, was increased in malignant vs non-malignant prostate (by 2-2.5 fold, p<0.0001). Operating characteristics indicate sensitivity in the range of 0.68 to 0.74; combination of markers in a logistic regression model demonstrates further improvement in diagnostic power. Triple-labeled immunofluorescence (BTF3, HINT1 and NDRG1) in tissue Toxoflavin array showed a significant (p<0.02) change in co-localization coefficients for BTF3 and NDRG1 co-expression in biochemical relapse vs non-relapse cancer epithelium. BTF3, HINT1, NDRG1 and ODC1 could be developed as epithelial specific biomarkers for tissue based diagnosis and stratification of prostate cancer. Introduction Prostate carcinoma is a disease Toxoflavin of the epithelium, the most common cancer in men and the cause of considerable morbidity and mortality . Each year, over 30,000 men are diagnosed of prostate cancer and over 10,000 die of the disease in the UK. In 2010 2010, 217,730 new cases of prostate cancer were diagnosed in the US, with 32,050 American males dying of the disease . Diagnosis and prognosis of prostate cancer is based on tissue morphology Sav1 from biopsies (~1 million procedures in USA and ~70,000 in the UK / year). First time biopsies identify cancer in 38% of cases whereas equivocal diagnosis or false negatives constitute ~25-30% of cases . Descriptors of aggressiveness (e.g. Gleason grade) determine cancer management and therapy but have significant drawbacks and high variance, particularly for low grade cancers. Immunohistochemistry (IHC) is used in resolving equivocal diagnosis, however, most IHC biomarkers have been identified using subjective (scoring) analysis introducing large variability . For organ confined disease prostate biopsy remains a critical clinical tool, however, there is a need to resolve false negatives and refine diagnosis. By identifying cancers that have good prognosis over-treatment could be reduced but there are no quantitative protein markers to enhance the quality of diagnosis. A reproducible, quantitative approach could greatly facilitate this process. Discovery of IHC markers, largely, and their analysis, is executed by semi quantitative strategies (e.g. credit scoring of tissues sections stained using a chromo- or fluorophore) with huge inter-observer mistakes [4,5]. Credit scoring of the strength of the chromophore (or fluorophore) consists of visual inspection accompanied by a rating within a predetermined range with the experimenter. A strategy based upon visible observation of patterned items like mammalian tissues, with distinct structures, or visible assesment of strength of the light indication as performed for IHC credit scoring, entails Toxoflavin with serious restrictions of conception of wisdom and illuminance, generally  as well as for evaluation of prostate carcinoma,  specifically. A further drawback of utilizing a subjective credit scoring approach is normally that selecting target proteins to become investigated gravitates to the extremes (either extremely expressed in cancers (e.g. EZH) or absent in cancers (e.g. cytokeratins 5 and 6). Which means that a Toxoflavin lot of significant natural changes that undoubtedly take place within these extremes aren’t found and can’t be employed for the knowledge of the systems of carcinogenesis or created as biomarkers for medical diagnosis, or prognosis or stratification of cancers. Quantitative IHC  can recognize novel biomarkers within an impartial, reproducible way, and together with fluorescent probes could possibly be helpful for the last mentioned. Chances are that not merely the appearance but co-localization of several protein may also transformation seeing that.