Prognostic values of morphological and clinical parameters in pT2-pT3 prostate cancer in elderly people

Prostate cancer is a disease of elderly men, the incidence of which increases in an age dependent manner. This study presents the correlation of clinical and morphological parameters in locally confined (pT2) and locally advanced (pT3) prostate cancer. We analyzed a group of elderly men treated with radical prostatectomy in the period 1999-2008 in the University Hospital Rijeka. We found no statistical association between pT stage and age categories, preoperative prostate-specific antigen, digitorectal examination and biopsy Gleason score. There was a significant correlation of higher Gleason score in prostate specimens after radical prostatectomy and a higher frequency of a positive surgical margin in tumors with pT3 than in pT2 stage (p = 0.003; p = 0.011 respectively). Recurrence-free survival was shorter in patients with tumors with positive surgical margins as well as in patients with pT3 stage (p = 0.030; p = 0.001 respectively). We conclude that higher tumor grade and positive surgical margins are indicators of a worse prognosis in our patients.     

Antioxidant system activation in prostate cancer

The activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) and the levels of copper, zinc, and malondialdehyde were determined in 21 age-, sex-, and body-mass-index-matched prostate cancer patients; 50 patients diagnosed with benign prostatic obstruction (BPO) were compared to 50 healthy male subjects acting as controls. The patients were divided into two groups depending on the stage of the disease (group 1 [organ-confined] and group II [advanced disease]) and into three subgroups according to differentiation criteria: subgroup A (n=5, Gleason sum 2–4, well differentiated); subgroup B (n=9, Gleason sum 5–7, moderately differentiated), and subgroup C (n=7, Gleason sum 8–10, poorly differentiated). The MDA levels were higher and the antioxidant activity and Zn levels lower in the prostate cancer groups than in the healthy control and BPO groups. These results confirm the value of therapies aimed at increasing the antioxidant capacity and encourage the use of plasma and erythrocyte Zn levels in the differential diagnosis of BPO and prostate cancer. The MDA levels can be used in the diagnosis and follow-up of prostate cancer.     

The application of the RT-PCR method for the staging of the prostate cancer progression

Molecular biology seems to bring more convincing markers for the detection of prostate cancer as well as the development of metastases than immunohistochemistry. The main goal of present work was to detect the expression of prostate specific antigen (PSA) and prostate-specific membrane antigen (PSM) genes in the micrometastases by the RT-PCR to assess the progression of prostate cancer. We analyzed 50 patients: 28 patients with clinically localized or locally advanced prostate cancer who underwent radical prostatectomy, 7 patients with clinically proven metastases, 8 patients with benign prostatic hyperplasia, and 7 healthy young men. The results of RT-PCR in the first group of 28 patients varied, however, they were in good correlation with the health status of the patients. Positive results of PSA and notably for PSM were good predictors of beginning metastasing process. Seven patients with metastatic disease had positive RT-PCR results both for PSA and PSM. All of the patients with benign prostatic hyperplasia and healthy young men had negative RT-PCR results for PSA and PSM. The study showed that positive RT-PCR results for PSA and especially for PSM correlated well with the progression of the disease and negative results reflected good health status of the patients.     

Serum vascular endothelial growth factor C level in patients with prostate cancer and benign prostatic hyperplasia

OBJECTIVE: To compare serum vascular endothelial growth factor C (VEGF-C) levels in patients with benign prostatic hyperplasia (BPH) and prostate cancer (PCa) and analyze VEGF-C levels in relation to clinicopathologic parameters. STUDY DESIGN: Fifty-eight patients with PCa and 61 patients with BPH were included in this study. Serum VEGF-C levels were assessed by enzyme-linked immunosorbent assay. RESULTS: The serum VEGF-C level for patients with PCa was 3,432.06 +/- 1,851.07 as opposed to 3,166.68 +/- 1,921.2 for patients with BPH. There was no statistically significant difference between the 2 groups (p = 0.4448). There was no correlation of VEGF-C to tumor stage, grading or the preoperative prostate-specific antigen values. CONCLUSION: We cannot recommend VEGF-C serum level as a marker for tumor growth in PCa.     

Prostate cancer vs hyperplasia: relationships with prostatic and adipose tissue fatty acid composition

The objective of the present study was to study whether adipose tissue and prostatic tissue fatty acid composition differentiates between prostate cancer and benign hyperplasia patients. In addition, the present investigation aimed at exploring the extent to which prostatic tissue fatty acid composition differentiates between prostate-confined cancer and extraprostatic disease including possible metastasis. The subjects were 71 male patients from the island of Crete. Half the patients (n=35) had been diagnosed with benign hyperplasia of the prostate, half with prostatic malignancy (n=36). Patients were examined at the outpatient clinic of the urology unit, University Hospital, Medical School, University of Crete. Relative to benign hyperplasia patients, cancer patients had elevated adipose tissue saturated and reduced monounsaturated fatty acid levels. Cancer patients had reduced prostate tissue stearic to oleic acid ratios and stearic acid levels as opposed to hyperplasia patients. The most pronounced difference between cancer patients and hyperplasia patients was a 3-fold elevated prostatic palmitoleic acid in the former group. Relative to benign hyperplasia patients, cancer patients had reduced prostate tissue arachidonic and docosahexaenoic acid levels. Finally, there was a significantly reduced omega-3/omega-6 polyunsaturated fatty acid ratio in the prostate cancer patient as opposed to the benign hyperplasia group. The pronounced elevations in prostatic tissue palmitoleic acid in cancer patients highlight a possible role of this fatty acid in neoplastic processes. The decreased arachidonic acid levels in cancer patients possibly stem from enhanced metabolism of arachidonic acid via lipoxygenase and cyclooxygenase pathways, and the formation of derivatives such as 5-HETE, 15-HETE, 12(S)-HETE and PGE(2).     

CyclinD1、CDK4、P16和结核菌L型感染在前列腺癌中的表达及临床意义

目的探讨CyclinD1、CDK4和P16在前列腺癌中的表达以及结核菌L型感染率及临床意义。方法应用免疫组化和抗酸染色等方法检测了65例前列腺癌（carcinoma of prostate,PCa）和30例良性前列腺增生（benignprostatic hyperplasia,BPH）中的CyclinD1、CDK4和P16的表达,以及结核菌L型的检出率。并对前列腺肿瘤主要临床资料和病理分级参数进行比较,用χ^2检验进行统计学处理。结果 CyclinD1、CDK4阳性表达前列腺癌明显高于前列腺增生（P〈0.01）;并与前列腺癌的临床分期、病理分级及淋巴结转移差异有统计学意义（P〈0.01-0.05）呈正相关。P16阳性表达前列腺增生明显高于前列腺癌（P〈0.01）;与前列腺癌的临床分期、病理分级及淋巴结转移差异有统计学意义（P〈0.01-0.05）呈负正相关。结核菌L型检出率前列腺癌明显高于前列腺增生;与前列腺癌的临床分期、病理分级及淋巴结转移差异有统计学意义（P〈0.05）。结论 CyclinD1、CDK4和P16在前列腺肿瘤中不同程度异常表达以及结核菌L型检出率与肿瘤的临床分期、病理分级和转移相关,因此研究CyclinD1、CDK4和P16的阳性表达和结核菌L型感染与前列腺癌发生发展中可能有协同作用,具有重要的临床应用价值。     

Tissue and serum levels of principal androgens in benign prostatic hyperplasia and prostate cancer

Androgens are considered to play a substantial role in pathogenesis of both benign prostatic hyperplasia (BPH) and prostate cancer. The importance of determination of androgen levels in tissue and serum for cancer progression and prognosis has been poorly understood. The aim of study was to find out hormonal differences in both diseases, their correlations between intraprostatic and serum levels and predicted value of their investigation. Testosterone, dihydrotestosterone, androstenedione and also epitestosterone were determined in prostate tissue from 57 patients who underwent transvesical prostatectomy for BPH and 121 patients after radical prostatectomy for prostate cancer. In 75 subjects with cancer and 51 with BPH the serum samples were analyzed for testosterone, dihydrotestosterone and SHBG. Significantly higher intraprostatic androgen concentrations, i.e. 8.85+/-6.77 versus 6.44+/-6.43 pmol/g, p<0.01 for dihydrotestosterone, and 4.61+/-7.02 versus 3.44+/-4.53 pmol/g, p<0.05 for testosterone, respectively, were found in patients with prostate cancer than in BPH. Higher levels in cancer tissue were found also for epitestosterone. However, no differences were found in serum levels. Highly significant correlations occurred between all pairs of intraprostatic androgens and also epitestosterone as well as between serum testosterone and dihydrotestosterone (p<0.001) in both BPH and cancer groups. Correlation was not found between corresponding tissue and serum testosterone and dihydrotestosterone, either in benign or cancer samples. The results point to importance of intraprostatic hormone levels for evaluation of androgen status of patients, contrasting to a low value of serum hormone measurement.     

Seminal Plasma as a Source of Prostate Cancer Peptide Biomarker Candidates for Detection of Indolent and Advanced Disease

Background

Extensive prostate specific antigen screening for prostate cancer generates a high number of unnecessary biopsies and over-treatment due to insufficient differentiation between indolent and aggressive tumours. We hypothesized that seminal plasma is a robust source of novel prostate cancer (PCa) biomarkers with the potential to improve primary diagnosis of and to distinguish advanced from indolent disease.

Methodology/Principal Findings

In an open-label case/control study 125 patients (70 PCa, 21 benign prostate hyperplasia, 25 chronic prostatitis, 9 healthy controls) were enrolled in 3 centres. Biomarker panels a) for PCa diagnosis (comparison of PCa patients versus benign controls) and b) for advanced disease (comparison of patients with post surgery Gleason score <7 versus Gleason score >7) were sought. Independent cohorts were used for proteomic biomarker discovery and testing the performance of the identified biomarker profiles. Seminal plasma was profiled using capillary electrophoresis mass spectrometry. Pre-analytical stability and analytical precision of the proteome analysis were determined. Support vector machine learning was used for classification. Stepwise application of two biomarker signatures with 21 and 5 biomarkers provided 83% sensitivity and 67% specificity for PCa detection in a test set of samples. A panel of 11 biomarkers for advanced disease discriminated between patients with Gleason score 7 and organ-confined (<pT3a) or advanced (≥pT3a) disease with 80% sensitivity and 82% specificity in a preliminary validation setting. Seminal profiles showed excellent pre-analytical stability. Eight biomarkers were identified as fragments of N-acetyllactosaminide beta-1,3-N-acetylglucosaminyltransferase, prostatic acid phosphatase, stabilin-2, GTPase IMAP family member 6, semenogelin-1 and -2. Restricted sample size was the major limitation of the study.

Conclusions/Significance

Seminal plasma represents a robust source of potential peptide makers for primary PCa diagnosis. Our findings warrant further prospective validation to confirm the diagnostic potential of identified seminal biomarker candidates.     

Effects of lycopene supplementation in patients with localized prostate cancer

Epidemiological studies have shown an inverse association between dietary intake of lycopene and prostate cancer risk. We conducted a clinical trial to investigate the biological and clinical effects of lycopene supplementation in patients with localized prostate cancer. Twenty-six men with newly diagnosed prostate cancer were randomly assigned to receive a tomato oleoresin extract containing 30 mg of lycopene (n = 15) or no supplementation (n = 11) for 3 weeks before radical prostatectomy. Biomarkers of cell proliferation and apoptosis were assessed by Western blot analysis in benign and cancerous prostate tissues. Oxidative stress was assessed by measuring the peripheral blood lymphocyte DNA oxidation product 5-hydroxymethyl-deoxyuridine (5-OH-mdU). Usual dietary intake of nutrients was assessed by a food frequency questionnaire at baseline. Prostatectomy specimens were evaluated for pathologic stage, Gleason score, volume of cancer, and extent of high-grade prostatic intraepithelial neoplasia. Plasma levels of lycopene, insulin-like growth factor-1, insulin-like growth factor binding protein-3, and prostate-specific antigen were measured at baseline and after 3 weeks of supplementation or observation. After intervention, subjects in the intervention group had smaller tumors (80% vs 45%, less than 4 ml), less involvement of surgical margins and/or extra-prostatic tissues with cancer (73% vs 18%, organ-confined disease), and less diffuse involvement of the prostate by high-grade prostatic intraepithelial neoplasia (33% vs 0%, focal involvement) compared with subjects in the control group. Mean plasma prostate-specific antigen levels were lower in the intervention group compared with the control group. This pilot study suggests that lycopene may have beneficial effects in prostate cancer. Larger clinical trials are warranted to investigate the potential preventive and/or therapeutic role of lycopene in prostate cancer.     

Prostate-specific antigen in prostate cancer

Prostate-specific antigen (PA) has been evaluated clinically as a tumor marker of prostate cancer with the use of enzyme immunoassay (EIA). For serodetection of prostate cancer, PA was assayed in a total of 1,109 sera. From mean +/- 3 S.D. of normal controls, upper cut-off values in males were decided as 2.5 and 1.2 ng/ml in Americans and Japanese, respectively. Serum PA values in prostate cancer patients were positive in 78% of Americans and 62% of Japanese. However, in benign prostatic hypertrophy (BPH) cases, a high false positive rate of 41% was observed in Americans. Simultaneous assays of serum PA and PAP showed high sensitivity and specificity in the detection of prostate cancer. This antigen could be used, as well as PAP, for monitoring prostate cancer patients. Furthermore, serum PA levels prior to treatment may express to some degree the malignant potential of the cancer. These results suggest that PA may be useful as a tumor marker of prostate cancer.     

Expression of CaT-like, a novel calcium-selective channel, correlates with the malignancy of prostate cancer

The regulation of intracellular Ca(2+) plays a key role in the development and growth of cells. Here we report the cloning and functional expression of a highly calcium-selective channel localized on the human chromosome 7. The sequence of the new channel is structurally related to the gene product of the CaT1 protein cloned from rat duodenum and is therefore called CaT-like (CaT-L). CaT-L is expressed in locally advanced prostate cancer, metastatic and androgen-insensitive prostatic lesions but is undetectable in healthy prostate tissue and benign prostatic hyperplasia. Additionally, CaT-L is expressed in normal placenta, exocrine pancreas, and salivary glands. New markers with well defined biological function that correlate with aberrant cell growth are needed for the molecular staging of cancer and to predict the clinical outcome. The human CaT-L channel represents a marker for prostate cancer progression and may serve as a target for therapeutic strategies.     

Selenium level in benign and cancerous prostate

The dietary microelement selenium (Se) has been proposed as a potential chemopreventive agent for prostate cancer. This element is present in various amounts in all tissues. Little information is available on Se level in patients with prostate gland disorders. The levels of Se in prostatic gland of patients with prostate cancer, benign prostate hyperplasia, and healthy controls were examined. The Se level for benign prostate hyperplasia (156±30.6 ng/g) was the same as in the control group (157±26.0 ng/g), but in the gland of prostate cancer patients (182±34.1 ng/g wet weight), the Se level was significantly (p<0.01) higher than in both healthy controls and benign prostate hyperplasia. Thus, the Se level in human healthy controls is lower than in kidney and liver but higher compared with other tissues.     

Reduced Kv1.3 potassium channel expression in human prostate cancer

The presence of Kv1.3 voltage-gated potassium channels in rat and human prostate epithelial cells has been previously reported. We examined, by immunohistochemistry, Kv1.3 levels in 10 normal human prostate, 18 benign prostatic hyperplasia (BPH) and 147 primary human prostate cancer (Pca) specimens. We found high epithelial expression of Kv1.3 in all normal prostate, 16 BPH and 77 (52%) Pca specimens. Compared to normal, Kv1.3 levels were reduced in 1 (6%) BPH specimen and in 70 (48%) Pca specimens. We found a significant inverse correlation between Kv1.3 levels and tumor grade (r = -0.25, P = 0.003) as well as tumor stage (r = -0.27, P = 0.001). Study of an additional 30 primary Pca specimens showed that 15 (50%) had reduced Kv1.3 immunostaining compared to matched normal prostate tissue. Our data suggest that in Pca reduced Kv1.3 expression occurs frequently and may be associated with a poor outcome.     

Epithelial Na,K-ATPase expression is down-regulated in canine prostate cancer; a possible consequence of metabolic transformation in the process of prostate malignancy

Background  

An important physiological function of the normal prostate gland is the synthesis and secretion of a citrate rich prostatic fluid. In prostate cancer, citrate production levels are reduced as a result of altered cellular metabolism and bioenergetics. Na, K-ATPase is essential for citrate production since the inward Na⁺ gradients it generates are utilized for the Na⁺ dependent uptake of aspartate, a major substrate for citrate synthesis. The objective of this study was to compare the expression of previously identified Na, K-ATPase isoforms in normal canine prostate, benign prostatic hyperplasia (BPH) and prostatic adenocarcinoma (PCa) using immunohistochemistry in order to determine whether reduced citrate levels in PCa are also accompanied by changes in Na, K-ATPase expression.     

An A/G polymorphism of core 2 branching enzyme gene is associated with prostate cancer

The expression of core 2 beta1,6-N-acetylglucosaminyltransferase-1 (C2GnT) is associated with development and progression of malignancy. Sequence analysis showed that the codon 152 of C2GnT has a polymorphism having GTT encoding valine or ATT encoding isoleucine. By examining the polymorphism in prostate cancer and benign prostatic hyperplasia patients, we found that the C2GnT G allele was more frequently observed in the prostate cancer group (p=0.015) than the control group. Men with the GG genotype had a 3.60-fold increased risk of prostate cancer, and men with the AG genotype had a 1.58-fold increased risk of prostate cancer compared with those with the AA genotype. The G allele was found to have a gene dosage effect for prostate cancer risk. No such risk was associated for benign prostatic hyperplasia. These results demonstrate that C2GnT A/G polymorphism is associated with the susceptibility to prostate cancer in a Japanese population.     

Serum early prostate cancer antigen (EPCA) level and its association with disease progression in prostate cancer in a Chinese population

Background

Early prostate cancer antigen (EPCA) has been shown a prostate cancer (PCa)-associated nuclear matrix protein, however, its serum status and prognostic power in PCa are unknown. The goals of this study are to measure serum EPCA levels in a cohort of patients with PCa prior to the treatment, and to evaluate the clinical value of serum EPCA.

Methods

Pretreatment serum EPCA levels were determined with an ELISA in 77 patients with clinically localized PCa who underwent radical prostatectomy and 51 patients with locally advanced or metastatic disease who received primary androgen deprivation therapy, and were correlated with clinicopathological variables and disease progression. Serum EPCA levels were also examined in 40 healthy controls.

Results

Pretreatment mean serum EPCA levels were significantly higher in PCa patients than in controls (16.84±7.60 ng/ml vs. 4.12±2.05 ng/ml, P<0.001). Patients with locally advanced and metastatic PCa had significantly higher serum EPCA level than those with clinically localized PCa (22.93±5.28 ng/ml and 29.41±8.47 ng/ml vs. 15.17±6.03 ng/ml, P = 0.014 and P<0.001, respectively). Significantly elevated EPCA level was also found in metastatic PCa compared with locally advanced disease (P<0.001). Increased serum EPCA levels were significantly and positively correlated with Gleason score and clinical stage, but not with PSA levels and age. On multivariate analysis, pretreatment serum EPCA level held the most significantly predictive value for the biochemical recurrence and androgen-independent progression among pretreatment variables (HR = 4.860, P<0.001 and HR = 5.418, P<0.001, respectively).

Conclusions

Serum EPCA level is markedly elevated in PCa. Pretreatment serum EPCA level correlates significantly with the poor prognosis, showing prediction potential for PCa progression.     

COX-2、Ki-67和结核菌L型感染在前列腺癌中的表达

目的探讨环氧合酶-2（COX-2）和Ki-67在前列腺癌中的表达以及结核菌L型感染率及临床意义。方法应用免疫组化、原位杂交和抗酸染色等方法检测了65例前列腺癌（carcinoma of prostate,PCa）和30例良性前列腺增生（benign prostatic hyperplasia,BPH）中的COX-2、Ki-67蛋白及mRNA的表达,以及结核菌L型的检出率;并对前列腺肿瘤主要临床资料和病理分级参数进行比较,用χ^2检验进行统计学处理。结果COX-2、Ki-67蛋白及mRNA阳性表达和结核菌L型检出率,前列腺癌明显高于前列腺增生（P〈0.001～0.05）。COX-2、Ki-67蛋白及mRNA阳性表达和结核菌L型检出率与前列腺癌的临床分期、病理分级有明显差异（P〈0.01～0.05）。淋巴结转移组中COX-2、Ki-67蛋白及mRNA的阳性表达率明显高于非转移组（P〈0.01）。结核菌L型检出率淋巴结转移组明显高于非转移组（P〈0.05）。结论COX-2、Ki-67蛋白及mRNA在前列腺肿瘤中不同程度异常表达以及结核菌L型检出率与肿瘤的临床分期、病理分级和转移呈正相关,提示2种基因均可作为判断前列腺癌生物学行为及患者预后参考指标。结核菌L型感染极有可能导致基因的变异或过表达,成为诱发肿瘤因素之一,它们可能有协同致瘤作用。     

The contribution of prostatic acid phosphatase and prostatic specific antigen in the diagnosis of prostatic cancer

Prostatic acid phosphatase (PAP) and prostatic specific antigen (PSA) were measured by immunochemical methods using test preparations from two different companies. In 66 patients with benign hyperplasia of the prostate a good correlation was found only between PSA levels (orthogonal regression analysis: y = 1.77 x -0.68; r = 0.995). Discrimination analysis between benign hyperplasia and new prostatic cancer (28 patients), using ROC curves, revealed a sensitivity for prostatic cancer of about 30 percent using both PAP methods and of about 58 percent using both PSA methods at the 95-percentile of benign hyperplasia. The PSA methods were both more sensitive in detecting prostatic cancer than the PAP methods.     

New gene expressed in prostate: a potential target for T cell-mediated prostate cancer immunotherapy

New gene expressed in prostate (NGEP) is a prostate-specific gene encoding either a small cytoplasmic protein (NGEP-S) or a larger polytopic membrane protein (NGEP-L). NGEP-L expression is detectable only in prostate cancer, benign prostatic hyperplasia and normal prostate. We have identified an HLA-A2 binding NGEP epitope (designated P703) which was used to generate T cell lines from several patients with localized and metastatic prostate cancer. These T cell lines were able to specifically lyse HLA-A2 and NGEP-expressing human tumor cells. NGEP-P703 tetramer binding assays demonstrated that metastatic prostate cancer patients had a higher frequency of NGEP-specific T cells when compared with healthy donors. Moreover, an increased frequency of NGEP-specific T cells was detected in the peripheral blood mononuclear cells of prostate cancer patients post-vaccination with a PSA-based vaccine, further indicating the immunogenicity of NGEP. These studies thus identify NGEP as a potential target for T cell-mediated immunotherapy of prostate cancer.