Prostatic Neoplasms: Stenman UH

Sturgeon CM, Duffy MJ, Stenman UH, Lilja H, Brünner N, Chan DW, Babaian R, Bast RC, Dowell B, Esteva FJ, Haglund C, Harbeck N, Hayes DF, Holten-Andersen M, Klee GG, Lamerz R, Looijenga LH, Molina R, Nielsen HJ, Rittenhouse H, Semjonow A, Shih IeM, Sibley P, Sölétormos G, Stephan C, Sokoll L, Hoffman BR, Diamandis EP, Anonymous00039. · Department of Clinical Biochemistry, Royal Infirmary of Edinburgh, Edinburgh, UK. · Clin Chem. · Pubmed #19042984 No free full text.

Abstract: BACKGROUND: Updated National Academy of Clinical Biochemistry (NACB) Laboratory Medicine Practice Guidelines for the use of tumor markers in the clinic have been developed. METHODS: Published reports relevant to use of tumor markers for 5 cancer sites--testicular, prostate, colorectal, breast, and ovarian--were critically reviewed. RESULTS: For testicular cancer, alpha-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase are recommended for diagnosis/case finding, staging, prognosis determination, recurrence detection, and therapy monitoring. alpha-Fetoprotein is also recommended for differential diagnosis of nonseminomatous and seminomatous germ cell tumors. Prostate-specific antigen (PSA) is not recommended for prostate cancer screening, but may be used for detecting disease recurrence and monitoring therapy. Free PSA measurement data are useful for distinguishing malignant from benign prostatic disease when total PSA is <10 microg/L. In colorectal cancer, carcinoembryonic antigen is recommended (with some caveats) for prognosis determination, postoperative surveillance, and therapy monitoring in advanced disease. Fecal occult blood testing may be used for screening asymptomatic adults 50 years or older. For breast cancer, estrogen and progesterone receptors are mandatory for predicting response to hormone therapy, human epidermal growth factor receptor-2 measurement is mandatory for predicting response to trastuzumab, and urokinase plasminogen activator/plasminogen activator inhibitor 1 may be used for determining prognosis in lymph node-negative patients. CA15-3/BR27-29 or carcinoembryonic antigen may be used for therapy monitoring in advanced disease. CA125 is recommended (with transvaginal ultrasound) for early detection of ovarian cancer in women at high risk for this disease. CA125 is also recommended for differential diagnosis of suspicious pelvic masses in postmenopausal women, as well as for detection of recurrence, monitoring of therapy, and determination of prognosis in women with ovarian cancer. CONCLUSIONS: Implementation of these recommendations should encourage optimal use of tumor markers.

Stenman UH. · No affiliation provided · Clin Chem. · Pubmed #10351981 links to  free full text

This publication has no abstract.

Koistinen H, Närvänen A, Pakkala M, Hekim C, Mattsson JM, Zhu L, Laakkonen P, Stenman UH. · Department of Clinical Chemistry, Biomedicum Helsinki, University of Helsinki and Helsinki University Central Hospital, 00014 Helsinki, Finland. · Biol Chem. · Pubmed #18627344 No free full text.

Abstract: The prostate produces several proteases, the most abundant ones being kallikrein-related peptidase 3 (KLK3, PSA) and KLK2 (hK2), which are potential targets for tumor imaging and treatment. KLK3 expression is lower in malignant than in normal prostatic epithelium and it is further reduced in poorly differentiated tumors, in which the expression of KLK2 is increased. KLK3 has been shown to inhibit angiogenesis, whereas KLK2 may mediate tumor growth and invasion by participating in proteolytic cascades. Thus, it may be possible to control prostate cancer growth by modulating the proteolytic activity of KLK3 and KLK2. We have developed peptides that very specifically stimulate the activity of KLK3 or inhibit that of KLK2. Using these peptides we have established peptide-based methods for the determination of enzymatically active KLK3. The first-generation peptides are unstable in vivo and are rapidly cleared from the circulation. Currently we are modifying the peptides to make them suitable for in vivo applications. We have been able to considerably improve the stability of KLK2-binding peptides by cyclization. In this review we summarize the possible roles of KLK3 and KLK2 in prostate cancer and then concentrate on the development of peptides that modulate the activity of these proteases.

van Gils MP, Stenman UH, Schalken JA, Schröder FH, Luider TM, Lilja H, Bjartell A, Hamdy FC, Pettersson KS, Bischoff R, Takalo H, Nilsson O, Mulders PF, Bangma CH. · Department of Urology, Erasmus MC, CA Rotterdam, The Netherlands. · Eur Urol. · Pubmed #16054748 No free full text.

Abstract: An overview is given of serum and urine prostate cancer markers that are currently under investigation and subsequently the P-Mark project is introduced. There are many markers showing promise to overcome the limitations of prostate specific antigen (PSA). Eventually, these markers should be able to increase the specificity in diagnosis, differentiate between harmless and aggressive disease and identify progression towards androgen independence at an early stage. In the P-Mark project, several recently developed, promising markers will be evaluated using clinically well-defined biorepositories. Following successful evaluation, these markers will be validated on a sample set derived from two large, European, prostate cancer studies and used for the identification of special risk groups in the general population. In addition, novel markers will be identified in the same biorepositories by different mass spectrometry techniques.

Stenman UH, Abrahamsson PA, Aus G, Lilja H, Bangma C, Hamdy FC, Boccon-Gibod L, Ekman P. · Department of Clinical Chemistry, Helsinki University Central Hospital, Helsinki University, Helsinki, Finland. · Scand J Urol Nephrol Suppl. · Pubmed #16019759 No free full text.

Abstract: The incidence of prostate cancer has increased dramatically during the last 10-15 years and it is now the commonest cancer in males in developed countries. The increase is mainly caused by the increasing use of opportunistic screening or case-finding based on the use of prostate-specific antigen (PSA) testing in serum. With this approach, prostate cancer is detected 5-10 years before giving rise to symptoms and on average 17 years before causing the death of the patient. While this has led to detection of prostate cancer at a potentially curable stage, it has also led to substantial overdiagnosis, i.e. detection of cancers that would not surface clinically in the absence of screening. A major challenge is thus to identify the cases that need to be treated while avoiding diagnosing patients who will not benefit from being diagnosed and who will only suffer from the stigma of being a cancer patient. It would be useful to have prognostic markers that could predict which patients need to be diagnosed and which do not. Ideally, it should be possible to measure these markers using non-invasive techniques, i.e. by means of serum or urine tests. As it is very useful for both early diagnosis and monitoring of prostate cancer, PSA is considered the most valuable marker available for any tumor. Although the prognostic value of PSA is limited, measurement of the proportion of free PSA has improved the identification of patients with aggressive disease. Furthermore, the rate of increase in serum PSA reflects tumor growth rate and prognosis but, due to substantial physiological variation in serum PSA, reliable estimation of the rate of PSA increase requires follow-up for at least 2 years. Algorithms based on the combined use of free and total PSA and prostate volume in logistic regression and neural networks can improve the diagnostic accuracy for prostate cancer, and assays for minor subfractions of PSA and other new markers may provide additional prognostic information. Markers of neuroendocrine differentiation are useful for the monitoring of androgen-independent disease and various bone markers are useful in patients with metastatic disease.

Stenman UH, Leinonen J, Zhang WM, Finne P. · Department of Clinical Chemistry, Helsinki University Central Hospital, Helsinki, FIN-00290, Finland. · Semin Cancer Biol. · Pubmed #10202130 No free full text.

Abstract: Prostate specific antigen (PSA) is serine protease produced at high concentrations by normal and malignant prostatic epithelium. It is mainly secreted into seminal fluid, where it digests the gel forming after ejaculation. Only minor amounts of PSA leak out into circulation from the normal prostate, but the release of PSA is increased in prostatic disease. Thus PSA is a sensitive serum marker for prostate cancer but its specificity is limited by a high frequency of falsely elevated values in men with benign prostatic hyperplasia (BPH). Approximately two-thirds of all elevated values (>4 microg/l) in men over 50 years of age are due to BPH. In serum, most of the PSA immunoreactivity consists of a complex between PSA and alpha1-antichymotrypsin (PSA-ACT) whereas approximately 5-40% are free. The proportion of PSA-ACT is larger and the free fraction is smaller in prostate cancer than in benign prostatic hyperplasia (BPH). Determination of the proportion of free PSA has become widely used to improve the cancer specificity of PSA especially in men with PSA values in the 'grey zone' (4-10 microg/l). PSA also occurs in complexes with other protease inhibitors and determination of these and other markers may further improve the diagnostic accuracy for prostate cancer. Interpretation of the results for many different markers is complicated, but this can be simplified by using statistical methods. The diagnostic accuracy can be further improved by using logistic regression or neural networks to estimate the combined impact of marker results and other findings like digital rectal examination (DRE), transrectal ultrasound (TRUS) and heredity.

Auvinen A, Määttänen L, Finne P, Stenman UH, Aro J, Juusela H, Rannikko S, Tammela TL, Hakama M. · School of Public Health, University of Tampere, Tampere, Finland. · Int J Cancer. · Pubmed #15300807 No free full text.

Abstract: We estimated the sensitivity of serum prostate-specific antigen (PSA) as a screening test for prostate cancer in the Finnish randomised, population-based prostate cancer screening trial. The study population consisted of 80,458 men aged 55-67 years identified from the national population registry and randomised to the screening or control arm of the trial. The screening algorithm was based on determination of serum PSA concentration. Test sensitivity was estimated based on interval cancer incidence during the first 4 years of follow-up among screening participants with a negative screening test. Interval cancers were defined as those occurring among men with a negative screening test. Altogether, 19 interval cancers were detected among 17,897 men with serum PSA < 3 ng/ml during the first screening interval. A further 5 cases were diagnosed among 811 men with PSA 3.0-3.9 ng/ml with a benign digital rectal examination or free total PSA ratio > or = 0.16. Test sensitivity based on serum PSA of 3 ng/ml was estimated to be 0.89 (95% confidence interval 0.84-0.93) and that based on PSA of 4 ng/ml combined with an ancillary test (digital rectal examination or free total PSA ratio in the PSA range 3.0-3.9) was 0.87 (0.82-0.92). Test sensitivity achieved with serum PSA in prostate cancer screening appears excellent in the context of a population-based effectiveness trial.

Finne P, Finne R, Bangma C, Hugosson J, Hakama M, Auvinen A, Stenman UH. · Department of Clinical Chemistry, University of Helsinki, Helsinki, Finland. · Int J Cancer. · Pubmed #15197788 No free full text.

Abstract: Our objective was to determine whether multivariate algorithms based on serum total PSA, the free proportion of PSA, age, digital rectal examination and prostate volume can reduce the rate of false-positive PSA results in prostate cancer screening more effectively than the proportion of free PSA alone at 95% sensitivity. A total of 1,775 consecutive 55- to 67-year-old men with a serum PSA of 4-10 microg/l in the European Randomized Study of Screening for Prostate Cancer were included. To predict the presence of cancer, multivariate algorithms were constructed using logistic regression (LR) and a multilayer perceptron neural network with Bayesian regularization (BR-MLP). A prospective setting was simulated by dividing the data set chronologically into one set for training and validation (67%, n = 1,183) and one test set (33%, n = 592). The diagnostic models were calibrated using the training set to obtain 95% sensitivity. When applied to the test set, the LR model, the BR-MLP model and the proportion of free PSA reached 92%, 87% and 94% sensitivity and reduced 29%, 36% and 22% of the false-positive PSA results, respectively. At a fixed sensitivity of 95% in the test set, the LR model eliminated more false-positive PSA results (22%) than the proportion of free PSA alone (17%) (p < 0.001), whereas the BR-MLP model did not (19%) (p = 0.178). The area under the ROC curve was larger for the LR model (0.764, p = 0.030) and the BR-MLP model (0.760, p = 0.049) than for the proportion of free PSA (0.718). A multivariate algorithm can be used to reduce unnecessary prostate biopsies in screening more effectively than the proportion of free PSA alone, but the algorithms will require updating when clinical practice develops with time.

Mäkinen T, Tammela TL, Stenman UH, Määttänen L, Aro J, Juusela H, Martikainen P, Hakama M, Auvinen A. · Department of Surgery, Seinäjoki Central Hospital, Seinäjoki, Finland. · Clin Cancer Res. · Pubmed #15073097 links to  free full text

Abstract: PURPOSE: Large randomized trials provide the only valid means of quantifying the benefits and drawbacks of prostate-specific antigen (PSA) screening, but the follow-up of ongoing studies is still too short to allow evaluation of mortality. We report here the intermediate indicators of screening efficacy from the second round of the Finnish trial. EXPERIMENTAL DESIGN: The Finnish trial, with approximately 80,000 men in the target population, is the largest component in the European Randomized Study of Screening for Prostate Cancer. The first round was completed in 1996-1999. Each year 8,000 men 55-67 years of age were randomly assigned to the screening arm, and the rest formed the control arm. Men randomized to the screening arm in 1996 were reinvited 4 years later, in 2000, and PSA was determined. RESULTS: Of the eligible 6415 men, 4407 (69%) eventually participated in the second round of screening. Of the first-round participants, up to 84% (3833 of 4556) attended rescreening. A total of 461 screenees (10.5%) had PSA levels of > or = 4 microg/liter. Altogether, 97 cancers were found, yielding an overall detection rate of 2.2% (97 of 4407). Seventy-nine cases were found among the 3833 second-time screenees (detection rate 2.1%) and 18 in those 574 men (3.1%) who had not participated previously. A PSA of > or = 4 microg/liter, but negative biopsy in the first screening round was associated with an up to 9-fold risk of cancer in rescreening relative to those with lower PSA levels at baseline. Ninety-one (94%) of all of the detected cancers were clinically localized. CONCLUSIONS: As surrogate measures of an effective screening program, both compliance as well as the overall and advanced prostate cancer detection rates remained acceptable. Men defined as screen-positive but with a negative confirmation of cancer at prevalence screen formed a high-risk group at rescreening.

Finne P, Stenman UH, Määttänen L, Mäkinen T, Tammela TL, Martikainen P, Ruutu M, Ala-Opas M, Aro J, Karhunen PJ, Lahtela J, Rissanen P, Juusela H, Hakama M, Auvinen A. · Department of Clinical Chemistry, University of Helsinki, Helsinki, Finland. · BJU Int. · Pubmed #14983949 No free full text.

This publication has no abstract.

Bylund A, Lundin E, Zhang JX, Nordin A, Kaaks R, Stenman UH, Aman P, Adlercreutz H, Nilsson TK, Hallmans G, Bergh A, Stattin P. · Department of Community Medicine and Rehabilitation Geriatric Medicine, University of Umeå, Sweden. · Eur J Cancer Prev. · Pubmed #14512806 No free full text.

Abstract: The short-term effects of rye bran bread intake in prostate cancer were investigated. Ten men with conservatively treated prostate cancer were randomised to a daily supplement of 295 g of rye bran bread and eight men to 275 g of wheat bread (control) with similar fibre content for three weeks. Blood samples, ultrasound-guided core biopsies of the prostate, and urine samples were taken. In the rye group, there was a significant increase in plasma enterolactone, and the apoptotic index increased significantly from 2.1% (SD 1.3) to 5.9% (SD 1.8), P<0.005 as measured by a TUNEL index in four cases in the rye group and seven cases in the control group. Besides a significant decrease in weight in both groups, only small changes were observed in plasma concentrations of prostate specific antigen (PSA), circulating sex hormones, excreted oestrogens, insulin-like growth factor (IGF)-I, and in the endothelial fibrinolytical system. High intake of rye bran bread is suggested to increase apoptosis in prostate tumours.

Finne P, Auvinen A, Aro J, Juusela H, Määttänen L, Rannikko S, Hakama M, Tammela TL, Stenman UH. · Department of Clinical Chemistry, Helsinki University Central Hospital, Biomedicum-Helsinki, A418a, P.O. Box 700 (Haartmaninkatu 8), FIN-00029 HUS, Finland. · Eur Urol. · Pubmed #12074779 No free full text.

Abstract: BACKGROUND AND OBJECTIVE: Approximately 70% of the men with an elevated serum prostate-specific antigen (PSA) identified in prostate cancer screening do not have prostate cancer. Other available diagnostic variables may be utilized to reduce the number of false positive PSA results, but few algorithms for calculation of the combined impact of multiple variables are available. The objective of this study was to establish nomograms showing the probability of detecting prostate cancer at biopsy on the basis of total PSA, and the percentage of free PSA in serum, prostate volume and digital rectal examination (DRE) findings. METHODS: In a randomized, population-based prostate cancer screening trial 10284 men aged 55-67 years were screened during 1996 and 1997 in two metropolitan areas in Finland. Results for men (n=758) with a serum PSA of 4-20 microg/l were used to establish the risk nomograms. Of these 200 (26%) had prostate cancer at biopsy. RESULTS: Prostate cancer probability depended most strongly on the percentage of free PSA. Total PSA, prostate volume, and DRE also contributed to prostate cancer probability, whereas age and family history of prostate cancer did not. More false positive PSA results could be eliminated by using the multivariate risk model rather than the percentage of free PSA (p<0.001) or PSA density (p=0.003) alone. CONCLUSIONS: Wide variation in probability of detecting prostate cancer among screened men with a serum PSA of 4-20 microg/l was observed. The nomograms established can be used to avoid or defer biopsy in men with a low prostate cancer probability in spite of a serum PSA level exceeding 4 microg/l.

Mäkinen T, Tammela TL, Stenman UH, Määttänen L, Rannikko S, Aro J, Juusela H, Hakama M, Auvinen A. · Finnish Cancer Registry, Department of Clinical Chemistry, Helsinki University Central Hospital, Helsinki. · J Clin Oncol. · Pubmed #12039927 No free full text.

Abstract: PURPOSE: Early detection of prostate cancer has been recommended for men with affected first-degree relatives despite the lack of evidence for mortality reduction. We therefore evaluated the impact of family history in the Finnish prostate cancer screening trial. PATIENTS AND METHODS: Approximately 80,000 men were identified from the population register for the first screening round. Of the 32,000 men randomized to the screening arm, 30,403 were eligible at the time of invitation. A blood sample was drawn from the participants (n = 20,716), and serum prostate-specific antigen (PSA) was determined. Men with a PSA level > or = 4.0 ng/mL were referred for prostate biopsy. Information on family history was obtained through a self-administered questionnaire at baseline. RESULTS: A total of 964 (5%) of the 20,716 screening participants had a positive family history, and 105 (11%) were screening-positive. Twenty-nine tumors were diagnosed, corresponding to a detection rate of 3.0% (29 of 964) and a positive predictive value of 28% (29 of 105). Of the 19,347 men without a family history, 1,487 (8%) had a PSA level > or = 4.0 ng/mL. The detection rate was 2.4% (462 of 19,347) and the positive predictive value was 31% (462 of 1,487). The risk associated with a positive family history was not substantially increased (rate ratio, 1.3; 95% confidence interval, 0.9 to 1.8). The results were not affected by the age of the screenee or age at diagnosis of the affected relative. The program sensitivity was 6% (29 of 491) (ie, selective screening policy would have missed 94% of cancers in the population). No differences were seen in the characteristics of screen-detected cancers by family history. CONCLUSION: Our findings provide no support for selective screening among men with affected relatives.

Isola J, Auvinen A, Poutiainen M, Kakkola L, Järvinen TA, Määttänen L, Stenman UH, Tammela T, Hakama M, Visakorpi T. · Laboratory of Cancer Genetics, Institute of Medical Technology and School of Public Health, University of Tampere, Finland. · J Urol. · Pubmed #11342919 No free full text.

Abstract: PURPOSE: It is not known whether screening of asymptomatic men with prostate specific antigen (PSA) decreases the mortality of prostate cancer. We evaluated the extent to which PSA screening identifies clinically significant prostate cancer by analyzing markers of biological aggressiveness. MATERIALS AND METHODS: We compared prostate cancer in 56 patients in the screening and 21 in the randomized control arm of a population based cohort of 8,975 men 55 to 67 years old participating in the Finnish arm of the European Randomized Study of Screening for Prostate Cancer to 47 clinically detected organ confined, 30 clinically detected metastatic and 16 latent prostate tumors identified at autopsy in 46 consecutive subjects. Biological aggressiveness was determined by histological grading using the Gleason and Mostofi scales, tumor proliferation rate by Ki-67 immunostaining, p53 over expression by immunostaining and aneuploidy by fluorescence in situ hybridization using formalin fixed, paraffin embedded tumor specimens. RESULTS: A total of 56 neoplasms were detected in 2,781 men (2%) who participated in PSA screening and 21 were detected in 5,975 nonscreened controls (0.35%) during the study period. Disease in nonscreened controls more often involved a high tumor proliferation rate (p = 0.004) and p53 over expression (p = 0.015) than screening detected disease. At least 1 feature of biological aggressiveness was present in 19% of latent, 34% of screening detected, 51% of clinically detected and organ confined, 62% of randomized control and 87% of metastasis cases. Of the screening detected tumors defined as biologically aggressive 74% were identified at organ confined stages pT1-2N0M0. CONCLUSIONS: PSA screening detects a significant number of biologically aggressive cancers at an early clinical stage, implying that screening may decrease mortality.

Hakama M, Aro J, Auvinen A, Juusela H, Määttänen L, Stenman UH, Tammela TL. · Cancer Epidemiology Unit, Tampere School of Public Health, University of Tampere, Finland. · Eur Urol. · Pubmed #11340285 No free full text.

This publication has no abstract.

Finne P, Auvinen A, Koistinen H, Zhang WM, Määttänen L, Rannikko S, Tammela T, Seppälä M, Hakama M, Stenman UH. · Department of Clinical Chemistry, Helsinki University Central Hospital, Finland. · J Clin Endocrinol Metab. · Pubmed #10946875 links to  free full text

Abstract: High serum levels of insulin-like growth factor I (IGF-I) and low levels of IGF-binding protein-3 (IGFBP-3) have been shown to correlate with increased prostate cancer risk. To evaluate this, IGF-I, IGFBP-3, and prostate-specific antigen (PSA) were measured in serum from 665 consecutive men (179 with prostate cancer), aged 55-67 yr, with elevated serum prostate-specific antigen (PSA; > or = 4 microg/L) in a screening trial. Men in the highest quartile of IGF-I levels had an odds ratio (OR) for prostate cancer of 0.50 [95% confidence interval (CI) 0.26-0.97] when adjusting for serum IGFBP-3. IGFBP-3 itself was not significantly associated with prostate cancer risk (OR, 1.24; 95% CI, 0.68-2.24). Prostate volume was larger in men without than in those with prostate cancer (P < 0.001), and after adjustment for prostate volume, the negative association between serum IGF-I and prostate cancer risk was no longer significant (OR, 0.57; 95% CI, 0.28-1.16). In screen-positive men with elevated serum PSA, serum IGF-I is not a useful diagnostic test for prostate cancer, but it may be associated with benign prostatic hyperplasia and enlargement.

Zhang WM, Finne P, Leinonen J, Vesalainen S, Nordling S, Stenman UH. · Departments of Clinical Chemistry, Urology, and Pathology, Helsinki University Central Hospital, FIN-00290 Helsinki, Finland. · Clin Chem. · Pubmed #10351990 links to  free full text

Abstract: BACKGROUND: Prostate-specific antigen (PSA) occurs in serum both free and in complex with protease inhibitors. The complex with alpha1-antichymotrypsin (ACT) is the major form in serum, and the proportion of PSA-ACT is higher in prostate cancer (PCa) than in benign prostatic hyperplasia (BPH). PSA also forms a complex with alpha1-protease inhibitor (API) in vitro, and the PSA-ACT complex has been detected in serum from patients with prostate cancer. The aim of the present study was to develop a quantitative method for the determination of PSA-API and to determine the serum concentrations in patients with PCa and BPH. METHODS: The assay for PSA-API utilizes a monoclonal antibody to PSA as capture and a polyclonal antibody to API labeled with a Eu-chelate as a tracer. For calibrators, PSA-API formed in vitro was used. Serum samples were obtained before treatment from 82 patients with PCa, from 66 patients with BPH, and from 22 healthy females. RESULTS: The concentrations of PSA-API are proportional to the concentrations of total PSA. PSA-API comprises 1.0-7.9% (median, 2.4%) of total immunoreactive PSA in PCa and 1.3-12.2% (median, 3.6%) in BPH patients with serum PSA concentrations >4 microgram/L. In patients with 4-20 microgram/L total PSA, the proportion of PSA-API serum is significantly higher in BPH (median, 4.1%) than in PCa (median, 3. 2%; P = 0.02). CONCLUSIONS: The proportion of PSA-API in serum is lower in patients with PCa than in those with BPH. These results suggest that PSA-API is a potential adjunct to total and free PSA in the diagnosis of prostate cancer.

Määttänen L, Auvinen A, Stenman UH, Rannikko S, Tammela T, Aro J, Juusela H, Hakama M. · Finnish Cancer Registry, Helsinki. · Br J Cancer. · Pubmed #10098761 No free full text.

Abstract: Approximately 20000 men 55-67 years of age from two areas in Finland were identified from the Population Registry and randomized either to the screening arm (1/3) or the control arm (2/3) of a prostate cancer screening trial. In the first round, the participation rate in the screening arm was 69%. Of the 5053 screened participants, 428 (8.5%) had a serum prostate-specific antigen (PSA) concentration of 4.0 ng/ml or higher, and diagnostic examinations were performed on 399 of them. A total of 106 cancers were detected among them corresponding to a positive predictive value of 27%, which is comparable with mammography screening for breast cancer. The prostate cancer detection rate based on a serum PSA concentration of 4.0 ng ml(-1) or higher was 2.1%. Approximately nine out of ten screen-detected prostate cancers were localized (85% clinical stage T1-T2) and well or moderately differentiated (42% World Health Organization (WHO) grade I and 50% grade II), which suggests a higher proportion of curable cancers compared with cases detected by other means.

Jhavar S, Brewer D, Edwards S, Kote-Jarai Z, Attard G, Clark J, Flohr P, Christmas T, Thompson A, Parker M, Shepherd C, Stenman UH, Marchbank T, Playford RJ, Woodhouse C, Ogden C, Fisher C, Kovacs G, Corbishley C, Jameson C, Norman A, De-Bono J, Bjartell A, Eeles R, Cooper CS. · Institute of Cancer Research, Male Urological Cancer Research Centre, Sutton, Surrey, UK. · BJU Int. · Pubmed #19040532 No free full text.

Abstract: OBJECTIVE: To integrate the mapping of ERG alterations with the collection of expression microarray (EMA) data, as previous EMA analyses have failed to consider the genetic heterogeneity and complex patterns of ERG alteration frequently found in cancerous prostates. MATERIALS AND METHODS: We determined genome-wide expression levels with GeneChip Human Exon 1.0 ST arrays (Affymetrix, Santa Clara, CA, USA) using RNA prepared from 35 specimens of prostate cancer from 28 prostates. RESULTS: The expression profiles showed clustering, in unsupervised hierarchical analyses, into two distinct prostate cancer categories, with one group strongly associated with indicators of poor clinical outcome. The two categories are not tightly linked to ERG status. By analysis of the data we identified a subgroup of cancers lacking ERG rearrangements that showed an outlier pattern of SPINK1 mRNA expression. There was a major distinction between ERG rearranged and non-rearranged cancers that involves the levels of expression of genes linked to exposure to beta-oestradiol, and to retinoic acid. CONCLUSIONS: Expression profiling of prostate cancer samples containing single patterns of ERG alterations can provide novel insights into the mechanism of prostate cancer development, and support the view that factors other than ERG status are the major determinants of poor clinical outcome.

Tomlins SA, Rhodes DR, Yu J, Varambally S, Mehra R, Perner S, Demichelis F, Helgeson BE, Laxman B, Morris DS, Cao Q, Cao X, Andrén O, Fall K, Johnson L, Wei JT, Shah RB, Al-Ahmadie H, Eastham JA, Eggener SE, Fine SW, Hotakainen K, Stenman UH, Tsodikov A, Gerald WL, Lilja H, Reuter VE, Kantoff PW, Scardino PT, Rubin MA, Bjartell AS, Chinnaiyan AM. · Michigan Center for Translational Pathology, University of Michigan Medical School, Ann Arbor, MI 48109, USA. · Cancer Cell. · Pubmed #18538735 No free full text.

Abstract: ETS gene fusions have been characterized in a majority of prostate cancers; however, the key molecular alterations in ETS-negative cancers are unclear. Here we used an outlier meta-analysis (meta-COPA) to identify SPINK1 outlier expression exclusively in a subset of ETS rearrangement-negative cancers ( approximately 10% of total cases). We validated the mutual exclusivity of SPINK1 expression and ETS fusion status, demonstrated that SPINK1 outlier expression can be detected noninvasively in urine, and observed that SPINK1 outlier expression is an independent predictor of biochemical recurrence after resection. We identified the aggressive 22RV1 cell line as a SPINK1 outlier expression model and demonstrate that SPINK1 knockdown in 22RV1 attenuates invasion, suggesting a functional role in ETS rearrangement-negative prostate cancers.

Koistinen H, Wohlfahrt G, Mattsson JM, Wu P, Lahdenperä J, Stenman UH. · Department of Clinical Chemistry, Biomedicum Helsinki, University of Helsinki, Helsinki University Central Hospital, Finland. · Prostate. · Pubmed #18500692 No free full text.

Abstract: BACKGROUND: Prostate-specific antigen (PSA or KLK3) has been shown to inhibit angiogenesis, but it might also have tumor promoting activities. Thus, it may be possible to modulate prostate cancer growth by stimulating or inhibiting the activity of PSA. To this end we have previously identified peptides that stimulate the activity of PSA. As peptides have several limitations as drug molecules, we screened a chemical library to find drug-like compounds that could be used to modulate the function(s) of PSA. METHODS: Almost 50,000 compounds were analyzed for their ability to modulate PSA activity towards a fluorescent PSA-substrate. The ability of the most active compounds to affect the anti-angiogenic activity of PSA was analyzed by human umbilical vein endothelial cell (HUVEC) tube formation assay. RESULTS: In the initial screening we identified two compounds that inhibited PSA activity. Based on these, similar compounds were selected and tested for activity to define structure-activity relationships. Several compounds with micromolar IC50-values were found, but they were not entirely specific towards PSA, e.g., they inhibited chymotrypsin, which has similar substrate specificity as PSA. However, it was possibly to improve the selectivity of the compounds towards PSA by small structural changes. These compounds inhibited the anti-angiogenic activity of PSA in the HUVEC model, proving that the proteolytic activity of PSA is essential for inhibition of angiogenesis. CONCLUSIONS: We found several PSA inhibitors that could be useful tools for studying the role of PSA in cancer models and in normal physiology as showed in angiogenesis model.

Finne P, Auvinen A, Määttänen L, Tammela TL, Ruutu M, Juusela H, Martikainen P, Hakama M, Stenman UH. · Department of Clinical Chemistry, Helsinki University Central Hospital, Helsinki, Finland. · Eur Urol. · Pubmed #18006214 No free full text.

Abstract: OBJECTIVES: The percentage of free prostate-specific antigen (%fPSA) improves the diagnostic accuracy for prostate cancer when the serum level of total PSA (tPSA) is elevated. Approximately 14% of men with a tPSA below 3 microg/l have prostate cancer on biopsy, but the diagnostic value of %fPSA in such men is rather unknown. The purpose was to estimate the impact of %fPSA on future prostate cancer risk among men with a normal tPSA in prostate cancer screening. SUBJECTS AND METHODS: The first round of the Finnish arm of the European Randomized Trial for Screening of Prostate Cancer in 1996 to 1999 comprised 20,793 men aged 55-67 yr. Screen-negative men (tPSA level below 3.0 microg/l, n=17,680) were followed up until the end of 2003. Cumulative risk of prostate cancer was calculated as a function of %fPSA. RESULTS: During the median follow-up of 5.8 yr (range, 0-7.7 yr), 327 men were diagnosed with prostate cancer and 25% of them had a Gleason score of 7 or higher. Five years after the first screening, cumulative risk of prostate cancer was 1.7% (95%CI, 1.5-1.9%). Men with a %fPSA in the lowest quartile (<14.2%) showed a 6.9-fold risk compared with those with a level in the highest quartile (>23.7%). CONCLUSIONS: In men with a low serum tPSA, a low %fPSA is a strong predictor of later diagnosis of prostate cancer.

Stephan C, Xu C, Finne P, Cammann H, Meyer HA, Lein M, Jung K, Stenman UH. · Department of Urology, Charité-Universitätsmedizin Berlin, Campus Charité Mitte, Berlin, Germany. · Urology. · Pubmed #17688922 No free full text.

Abstract: OBJECTIVES: Different artificial neural networks (ANNs) using total prostate-specific antigen (PSA) and percentage of free PSA (%fPSA) have been introduced to enhance the specificity of prostate cancer detection. The applicability of independently trained ANN and logistic regression (LR) models to different populations regarding the composition (screening versus referred) and different PSA assays has not yet been tested. METHODS: Two ANN and LR models using PSA (range 4 to 10 ng/mL), %fPSA, prostate volume, digital rectal examination findings, and patient age were tested. A multilayer perceptron network (MLP) was trained on 656 screening participants (Prostatus PSA assay) and another ANN (Immulite-based ANN [iANN]) was constructed on 606 multicentric urologically referred men. These and other assay-adapted ANN models, including one new iANN-based ANN, were used. RESULTS: The areas under the curve for the iANN (0.736) and MLP (0.745) were equal but showed no differences to %fPSA (0.725) in the Finnish group. Only the new iANN-based ANN reached a significant larger area under the curve (0.77). At 95% sensitivity, the specificities of MLP (33%) and the new iANN-based ANN (34%) were significantly better than the iANN (23%) and %fPSA (19%). Reverse methodology using the MLP model on the referred patients revealed, in contrast, a significant improvement in the areas under the curve for iANN and MLP (each 0.83) compared with %fPSA (0.70). At 90% and 95% sensitivity, the specificities of all LR and ANN models were significantly greater than those for %fPSA. CONCLUSIONS: The ANNs based on different PSA assays and populations were mostly comparable, but the clearly different patient composition also allowed with assay adaptation no unbiased ANN application to the other cohort. Thus, the use of ANNs in other populations than originally built is possible, but has limitations.

Wirén S, Stocks T, Rinaldi S, Hallmans G, Bergh A, Stenman UH, Kaaks R, Stattin P. · Department of Surgical and Perioperative Sciences, Urology and Andrology, Umeå University, Umeå, Sweden. · Prostate. · Pubmed #17562541 No free full text.

Abstract: BACKGROUND: Androgens have been implicated in prostate tumorigenesis, but prospective studies have overall reported no association between circulating levels of androgens and risk of prostate cancer. However, some recent studies have shown that a high level of testosterone increase the risk of non-aggressive tumors but is associated with a decreased risk of aggressive tumors. METHODS: We prospectively measured plasma levels of total testosterone, androstanediol glucuronide (A-diol-g) and sex hormone binding globuline (SHBG) and calculated estimated levels of free testosterone, in a nested case-control study of 392 cases and 392 matched controls. RESULTS: None of the studied hormones were significantly associated with prostate cancer risk in the full study group or in subgroups according to tumor aggressiveness. Odds ratios in the full study group, for top versus bottom quartile, was for total testosterone 1.25 (95% CI = 0.79-2.00; P(trend) = 0.51); free testosterone, 1.31 (95% CI = 0.82-2.07; P(trend) = 0.35); A-diol-g, 0.88 (95% CI = 0.59-1.33; P(trend) = 0.77); and for SHBG, 1.01 (95% CI = 0.64-1.58; P(trend) = 0.94). CONCLUSIONS: We found no significant associations between androgen levels and risk of prostate cancer in this population-based, non-screened cohort.

Pakkala M, Hekim C, Soininen P, Leinonen J, Koistinen H, Weisell J, Stenman UH, Vepsäläinen J, Närvänen A. · Department of Chemistry, University of Kuopio, P.O. Box 1627, FIN-70211, Kuopio, and Department of Clinical Chemistry, Helsinki University Central Hospital, Finland. · J Pept Sci. · Pubmed #17436344 No free full text.

Abstract: Human glandular kallikrein (KLK2) is a highly prostate-specific serine protease, which is mainly excreted into the seminal fluid, but part of which is also secreted into circulation from prostatic tumors. Since the expression level of KLK2 is elevated in aggressive tumors and it has been suggested to mediate the metastasis of prostate cancer, inhibition of the proteolytic activity of KLK2 is of potential therapeutic value. We have previously identified several KLK2-specific linear peptides by phage display technology. Two of its synthetic analogs, A R R P A P A P G (KLK2a) and G A A R F K V W W A A G (KLK2b), show specific inhibition of KLK2 but their sensitivity to proteolysis in vivo may restrict their potential use as therapeutic agents. In order to improve the stability of the linear peptides for in vivo use, we have prepared cyclic analogs and compared their biological activity and their structural stability. A series of cyclic variants with cysteine bridges were synthesized. Cyclization inactivated one peptide (KLK2a) and its derivatives, while the other peptide (KLK2b) and its derivatives remained active. Furthermore, backbone cyclization of KLK2b improved significantly the resistance against proteolysis by trypsin and human plasma. Nuclear magnetic resonance studies showed that cyclization of the KLK2b peptides does not make the structures more rigid. In conclusion, we have shown that backbone cyclization of KLK2 inhibitory peptides can be used to increase stability without losing biological activity. This should render the peptides more useful for in vivo applications, such as tumor imaging and prostate cancer targeting.