Biological Behavior Of Prostate Cancer Research Articles

Identification of serum protein of prostate cancer with osseous metastasis

Objective To identify the biomarkers which can be used of estimating the biological behaviors of prostate cancer with osseous metastasis by SELDI-TOF-MS. Methods Screening for potential tumor biomarkers of serum samples from 19 prostate cancer patients and 35 prostate cancer patients with osseous metastasis by using the technology of SELDI-TOF-MS and CM 10 protein chips (Ciphergen Inc. USA).The PBS Ⅱ protein chip reader was used to analyze the CM10 protein chips and transform the protein information into the form of spectra. The protein contents of two groups in the same mass-to-charge ratio (M/Z value) were analyzed and preceded the analysis of variance by Biomarker Wizard software. The proteins whose contents in serum were significantly different, which was distinguished the correctly groups by Biomarker Pattern software. Results The contents of 4 proteins in the two groups were significantly different and the M/Z values of these 6 proteins were from 2000 to 20 000. The relative protein content of prostate cancer patients group was higher than that of Prostate Cancer patients with osseous metastasis group at the M/Z value of 2089,4281, 3507 and 4178 [(4.63±8.03) vs (9.88±10.77), (19.78±21.46) vs (26.73±19.41), (5.46±10.14) vs (8.10±8.74), (38.01 ±26.27) vs (45.25±20.40), (P＜0.05)]. The relative protein content of prostate cancer patients group was lower than that of prostate cancer patients with osseous metastasis group at the M/Z value of 15 900 and 16 081 [(11.52±16.80) vs (4.84±5.83), (8.55±12.64) vs (3.56±3.90), (P＜0.05)]. Conclusion The associated serum protein in prostate cancer with osseous metastasis can be quickly and exactly diagnosed by SELDI-TOF-MS with high sensitivity and specificity. This new method will be widely used in clinical application. Key words: Prostatic neoplasms; Neoplasm metastasis; Spectrometry, mass, matrix-assisted laser desorption-ionization

Eight‐plex iTRAQ analysis of variant metastatic human prostate cancer cells identifies candidate biomarkers of progression: An exploratory study

Due to the heterogeneity in the biological behavior of prostate cancer, biomarkers that can reliably distinguish indolent from aggressive disease are urgently needed to inform treatment choices. We employed 8-plex isobaric Tags for Relative and Absolute Quantitation (iTRAQ), to profile the proteomes of two distinct panels of isogenic prostate cancer cells with varying growth and metastatic potentials, in order to identify novel biomarkers associated with progression. The LNCaP, LNCaP-Pro5, and LNCaP-LN3 panel of cells represent a model of androgen-responsive prostate cancer, while the PC-3, PC-3M, and PC-3M-LN4 panel represent a model of androgen-insensitive disease. Of the 245 unique proteins identified and quantified (>or=95% confidence; >or=2 peptides/protein), 17 showed significant differential expression (>or=+/-1.5), in at least one of the variant LNCaP cells relative to parental cells. Similarly, comparisons within the PC-3 panel identified 45 proteins to show significant differential expression in at least one of the variant PC-3 cells compared with parental cells. Differential expression of selected candidates was verified by Western blotting or immunocytochemistry, and corresponding mRNA expression was determined by quantitative real-time PCR (qRT-PCR). Immunostaining of prostate tissue microarrays for ERp5, one of the candidates identified, showed a significant higher immunoexpression in pre-malignant lesions compared with non-malignant epithelium (P < 0.0001, Mann-Whitney U-test), and in high Gleason grade (4-5) versus low grade (2-3) cancers (P < 0.05). Our study provides proof of principle for the application of an 8-plex iTRAQ approach to uncover clinically relevant candidate biomarkers for prostate cancer progression.

Genetic Alterations at 13q14 May Correlate with Differences in the Biological Behavior of Prostate Cancer between Japanese and Caucasian Men

The incidence of prostate cancer and the resultant mortality rates in Japanese men are lower compared with the rates for Caucasians; however, the Gleason score at diagnosis is higher in Japanese men compared with Caucasians. Loss of 13q is one of the most common chromosomal alterations in prostate cancer. To elucidate the difference in the rate of loss of 13q between Japanese and Caucasian men, we examined the allelic imbalance (AI) on chromosome 13q in 32 Japanese and 39 German prostate cancer patients with a fluorescent polymerase chain reaction technique using 12 microsatellite markers. Benign and malignant histology was identified by a single pathologist and laser capture microdissection was used to gather cancer cells. Although there were no statistical differences in patient background characteristics, the frequency of AI at 13q14 (D13S1253) and at 13q21 (D13S166) was significantly higher in Japanese patients compared with German patients (p = 0.0128 and p = 0.0078, respectively). The frequency of AI at 13q14 was significantly higher in tumors with high Gleason scores (GS) compared with tumors with low GS (p = 0.0478). The present observations suggest that the frequency of genetic alterations at 13q14 may underlie differences in the biological behavior of prostate cancer between Japanese and Caucasian populations.

UP-1.130: Identification of Bone Metastasis Associated Serum Protein in Prostate Cancer by Two-Dimensional Polyacrylamide Gel Electrophoresis, Capillary Liquid Chromatography and Mass Spectrometry

Identifying biomarkers which can be used to estimate the biological behaviors of prostate cancer with bone metastasis by screening differentially expressed serum proteins of prostate cancer patients with and without bone metastasis.

Relationship of neuroendocrine differentiation to biological behavior of prostate cancer

To investigate the relationship between neuroendocrine differentiation (NED) in prostate cancer and hormone refractory prostate cancer. Fifty-five prostate cancer specimens were obtained from 55 patients following intermittent androgen blockade during operation of transurethral resection of prostate. Monoclonal antibody immunohistochemistry was used to detect the expression of chromogranin A (CgA), a specific marker of neuroendocrine cell in the specimens. Follow-up was conducted for 25 (5 - 85) months. Serum prostate specific antigen (PSA), bone scan, chest X-ray, and computerized tomography were performed regularly during follow-up. Twenty-six of the 55 specimens (47.3%) were positive in CaG, and 23 of the 35 tumors with the Gleason score >or= 7 was 66%, significantly higher than those of the lower-grade tumors (all P < 0.01). Most of the high-grade tumors showed small cluster pattern, and most of the low-grade tumors showed solitary scattered pattern. The numbers of NED cells in the stage III and IV tumors were 67% and 71.4% respectively, both significantly higher than that of the stage II tumors (25%, both P < 0.05), There was no correlation between the NE positive cell rate and preoperative PSA value (P > 0.05). Thirty cases progressed to a hormone-independent status within 18 (5 - 79) months (Group A), and the rest 25 cases remained not progressing within 31 (17 - 85) months (Group B). The NED rate of Group A was significantly higher than that of Group B (P < 0.05). Univariate analysis showed that NE positivity, Gleason >or= 7, stage IV, and bone metastasis were influential factors of clinical progression. Multivariate COX regression analysis showed that NED and pre-operational PSA value were independent prognostic factors of bone metastasis. NED is associated with poor prognosis and hormone refractory prostate cancer in patients with androgen deprivation therapy.

New blood‐based biomarkers for the diagnosis, staging and prognosis of prostate cancer

The introduction of prostate-specific antigen (PSA) has revolutionized the detection and management of patients with prostate cancer. Despite this there has always been a concern among clinicians about the usefulness of total PSA levels as a marker for prostate cancer. We discuss the use of calculated variables and molecular forms of PSA. The precursor forms of PSA have been associated with the presence and biological behaviour of prostate cancer. With recent advances in biotechnology, e.g. high-throughput molecular analyses, many potential blood biomarkers have been identified and are currently under investigation. Given the plethora of candidate biomarkers we discuss a selected group of novel blood-based biomarkers, e.g. human glandular kallikrein, early prostate cancer antigen, insulin-like growth factors, urokinase plasminogen activators, transforming growth factor-beta, interleukin-6, chromogranin A, and prostate secretory protein. While these and other markers have shown promise in early-phase studies, no single biomarker is likely to have the appropriate degree of certainty to dictate treatment decisions. Consequently, the future of cancer prognosis might rely on small panels of markers that can accurately predict cancer presence, stage and metastasis, and serve as prognosticators, targets, and/or surrogate endpoints of disease progression and response to therapy.

Comparison of Contrast Enhanced Color Doppler Targeted Biopsy to Conventional Systematic Biopsy: Impact on Gleason Score

Prostate cancer grading with Gleason score is an important prognostic factor. This prospective randomized study compares ultrasound systematic biopsy vs contrast enhanced color Doppler targeted biopsy for the impact on Gleason score findings. We examined 690 men (mean age 56 years, range 41 to 77) with a serum total prostate specific antigen of 1.25 ng/ml or greater, a free-to-total prostate specific antigen ratio less than 18% and/or a suspicious digital rectal examination. Contrast enhanced color Doppler targeted biopsies with a limited number of cores (5 or less) were performed in hypervascular areas of the peripheral zone during administration of the ultrasound contrast agent Sonovuetrade mark (Bracco, Milano, Italy). Ten systematic biopsies were obtained in a standard spatial distribution. Cancer detection rates and Gleason score were compared. Prostate cancer was identified in 221 of 690 subjects (32%) with a mean prostate specific antigen of 4.6 ng/ml (range 1.4 to 35.0). Prostate cancer was detected in 180 of 690 subjects (26%) with contrast enhanced color Doppler targeted biopsy and in 166 of 690 patients (24%) with systematic ultrasound biopsy. The Gleason score of all 180 cancers detected on contrast enhanced color Doppler targeted biopsy was 6 or higher (mean 6.8). The Gleason score of all 166 cancers detected on systematic biopsy ranged from 4 to 6 and mean Gleason score was 5.4. Contrast enhanced color Doppler targeted biopsy detected significantly higher Gleason scores compared to systematic biopsy (Wilcoxon rank sum test p <0.003). Contrast enhanced color Doppler targeted biopsy detected cancers with higher Gleason scores and more cancer than systematic biopsy. Therefore, contrast enhanced color Doppler seems to be helpful in the grading of prostate cancer, which is important for defining prognosis and deciding treatment.

DNA sequence copy number aberrations in prostate cancers: a comparison of comparative genomic hybridization data between Japan and European countries

Incidence of prostate cancer in Japan and resultant mortality rates are lower than in Western countries. To elucidate the reasons behind this, the genetic characteristics of prostate cancer in Japanese patients were investigated. Comparative genomic hybridization was applied in 27 cases of prostate cancers in Japanese patients. Frequent gains were found at Xq, 8q, Xp, and 7q and frequent losses at 8p, 6q, 2q, 16q, and 17p (in decreasing order of frequency). Loss of 6q was frequently detected in both early and advanced tumors. Gains of 7q and 8q and loss of 8p were more frequent in advanced than early tumors. The frequency of 13q loss in primary tumors was significantly lower in patients in Japan than in European countries. These data suggest that a loss of 6q is associated with the development of prostate cancer, and that gains of 7q and 8q and a loss of 8p are linked with cancer progression. The frequency of 13q loss may imply differences in biological behavior of prostate cancer between Japan and Western countries.

Genetic pathways and new progression markers for prostate cancer suggested by microsatellite allelotyping.

At diagnosis, the biological behavior of prostate cancer is uncertain, making the choice of an adequate therapy option difficult. Performing microsatellite allelotyping on a large series of consecutive prostate cancers procured during radical prostatectomy at our institution, we sought to identify molecular markers associated with disease progression. A total of 156 consecutive fresh tumor samples was prospectively collected and macroscopically dissected from the whole prostatectomy specimen immediately after operation. Histologically 100 samples contained >75% tumor cells and were therefore enrolled in the microsatellite allelotyping, using a total of 24 polymorphic markers for the chromosomal regions 5p, 5q, 7q, 8p, 9p, 9q, 13q, 17p, 17q, and 18q. Fresh paired normal and tumor DNA was investigated in fluorescent microsatellite analysis with automated laser product detection. The incidence of tumor-DNA alterations [loss of heterozygosity or allelic imbalance (AI)] was highest for chromosomal regions 13q and 8p with 72 and 71%, respectively, followed by chromosomes 7q, 18q, 5q, and 17p with 57, 53, 41, and 39%, respectively. Alterations at chromosomes 8p, 9p, 13q, and 17p were significantly (P < 0.05) associated with advanced tumor stage, whereas AI at 8p and 17p was also associated with high Gleason score (P < 0.05). AI at 5q and 9p was associated with regional lymph node metastasis (P < 0.05). The combination of AI at 8p and 13q was strongly associated with advanced tumor stage (P < 0.0001). With the obtained results, we are able to postulate three distinct pathways in prostate carcinogenesis, and we identified microsatellite markers of prognostic value.

Variations of components of the plasminogen activation system with the cell cycle in benign prostate tissue and prostate cancer.

Components of the fibrinolytic system are involved in tumor cell invasion and metastasis. Previous investigations suggested a cell cycle-dependent expression of urokinase-type plasminogen activator (u-PA) in epithelial cells. In order to determine a correlation of cell cycle phases with the fibrinolytic system, we investigated the expression of u-PA, tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor type 1 (PAI-1) in normal and tumor-containing prostate extracts and analyzed a possible relationship with flow cytometry-determined proliferative activity of the samples. Cell cycle phases were correlated with fibrinolytic parameters in prostate tissue. Samples were obtained from patients undergoing radical prostatectomy for prostate cancer and separated into two portions for DNA analysis and the detection of u-PA, t-PA, and PAI-1. Flow cytometric analysis was performed according to the Vindelov technique. The concentrations of u-PA, t-PA, and PAI-1 were determined from tissue extracts after homogenization by an enzyme-linked immunosorbent assay (ELISA) technique. Correlations of u-PA and t-PA expression with the frequency of G0/G1, S, G2M, S-phase fraction (SPF), and proliferation index (PI) for normal prostate and prostate cancer revealed no significant correlation. The only significant finding was observed in normal tissue revealing a positive correlation between PAI-1 expression and G0/G1 and a negative correlation with S-phase, SPF, and PI. No dependence of PAI-1 expression on different cell phases was found in prostate cancer. Furthermore, no significant correlation of u-PA, t-PA, and PAI-1 with cell cycles in organ-confined (<pT3a) and disseminated (> or = pT3a) tumors was found. No significant correlation in prostate cancer of components of the fibrinolytic system differentiated according to tumor grade or perineural tumor infiltration and cell cycle analysis was found. Only in highly differentiated G1 (Gleason 2-4) cancer, u-PA had a significant positive correlation with G2M-phase. Absence of a correlation between levels of components of the fibrinolytic system and cell cycle phases suggests that the reported association between increases of some of these components and aggressive biological behavior of prostate cancer is secondary to non-cell cycle-related mechanisms.

Prognostic and predictive factors in prostate cancer

Prostate cancer is a major public health problem in the Western world, and the second most common male malignancies in the European Union. Detection of the disease is possible at an early stage, using serum prostate specific antigen measurement and prostatic biopsies. To date, however, screening for prostate cancer has not been shown to be of benefit to patients in improving outcome. This is compounded by uncertainties surrounding treatment efficacy, as more men appear to die with prostate cancer than from it. Studies addressing these issues are underway in Europe and the U.S.A. Clinicians are currently unable to advise their patients with any degree of certainty as to the appropriateness of treatment for prostate cancer, because of their inability to differentiate tumours that will progress from those that will remain quiescent. This article reviews the various clinical, pathological and experimental markers available, and their value in providing prognostic information, which may assist clinicians and patients in making management decisions. Further research is still required to understand the biological behaviour of prostate cancer and to assess the value of screening and treatment efficacy in order to advise patients, clinicians and health care systems accordingly.

Relationship between neuroendocrine features and prognostic parameters in human prostate adenocarcinoma

The biological behaviour of prostate cancer is highly variable and prediction by the commonly employed prognostic parameters is not sufficient. The concept of neuroendocrine (NE) differentiation in prostate adenocarcinoma has recently received increasing attention due to possible implications for prognosis and therapy. Core needle biopsies from 142 newly diagnosed patients were immunohistochemically examined for the coexistence of NE differentiation using an antibody against chromogranin A (CgA). Circulating CgA was available in 106 of these patients. NE differentiation was found in 64 (45.1%) tumors. Among them 29 (20.4%) had CgA positive cells scattered or focally distributed in less than 5% per mm3 of tumor tissues, 26 (18.3%) between 5% and 10% and 9 (6.4%) more than 10%, respectively. There was a significant correlation between the extent of NE features and either Gleason score (P < 0.01) or stage of disease. Circulating CgA but not PSA correlated with immunohistochemical CgA (P < 0.03) particularly in metastatic cases. These data support the concept that NE differentiation in human prostate cancer has a negative prognostic significance. Circulating CgA levels reflect immunohistochemical findings.

FOCAL NEUROENDOCRINE DIFFERENTIATION LACKS PROGNOSTIC SIGNIFICANCE IN PROSTATE CORE NEEDLE BIOPSIES

Purpose The biological behavior of prostate cancer is highly variable and cannot sufficiently be predicted by histological criteria alone. New prognostic factors are needed in core needle biopsies before initial treatment decisions. We investigate the prognostic significance of focal neuroendocrine differentiation in core needle biopsies of prostate cancer. Materials and Methods Core needle biopsies from 105 untreated patients (mean age 71 years) were immunohistochemically examined for focal neuroendocrine differentiation using an antibody against chromogranin A. Tumor cell proliferation was assessed with Ki-67 labeling index autopsy reports. Results Focal neuroendocrine differentiation was found in 25% of the tumors. There was no association between the presence of focal neuroendocrine differentiation and Gleason score or Ki-67 labeling index. Tumor specific survival analysis revealed that high Gleason score and high Ki-67 labeling index were predictors of tumor specific death, whereas focal neuroendocrine differentiation failed to provide prognostic information. There was a significant increase in frequency and density of neuroendocrine differentiation between initial core needle biopsies and later specimens of secondary hormone resistant prostate cancer in 15 patients. Conclusions In contrast to high Gleason score and high Ki-67 labeling index, focal neuroendocrine differentiation is not a prognostic factor in core needle biopsies of prostate cancer. Focal neuroendocrine differentiation seems to appear more frequently and intensively in hormone resistant prostate cancer, supporting a role of neuroendocrine cells in the development of hormone refractory disease.

Association between in vivo iododeoxyuridine labeling, MIB-1 expression, malignancy grade and clinical stage in human prostate cancer.

Large variability in the biological behavior of prostate cancer makes prognostic markers important. The extent of tumor cell proliferation has been suggested as an important predictor of clinical outcome. Fifty-five patients suspected of having or with previously diagnosed prostate cancer were labeled in vivo with IdUrd (a thymidine analogue incorporated into DNA in S-phase cells) by intravenous infusion before transurethral resection. IdUrd-labeled cells and MIB-1-positive cells were detected by immunohistochemistry. We found statistically significant associations between the tumor cell proliferation rates measured by in vivo IdUrd labeling and MIB-1 expression in formalin-fixed paraffin-embedded tumors. Good correlations were also found between S-phase fraction, MIB-1 expression, clinical stage and malignancy grade. These results make larger retrospective studies on archival tissue meaningful.

Color doppler imaging in predicting the biologic behavior of prostate cancer: Correlation with disease-free survival

Objectives We investigated the association of transrectal color Doppler imaging (CDI) signal detection in localized prostate cancer with biologic behavior as assessed by tumor Gleason grade, seminal vesicle invasion, capsular and margin status, and actuarial biochemical freedom from relapse. Methods From 1991 to 1996, transrectal ultrasound with CDI and biopsy was performed in 2718 men using a 7.0-MHz probe optimized to detect color-coded blood flow within the gland and along the capsular margin. Color flow was graded on a scale from 0 to 2 + , with 0 and 1 + representing no detectable flow and normal flow, and 2+ indicating increased flow. Color flow maps were constructed in 47 men with clinically localized prostate cancer treated by radical prostatectomy (RP) and compared to their whole mount RP specimen step sections. Results Color flow detected within the index tumor was graded as 2+ in 22 of 47 patients and 0 or 1 + in the remaining 25. Tumors graded 2+ correlated with higher Gleason grade, higher incidence of seminal vesicle invasion, and higher relapse rate, with only 11 of 22 patients disease free based on undetectable prostate-specific antigen (PSA) levels. In contrast, 24 of 25 patients with tumors graded 0 or 1 + are free of biochemical relapse with a median follow-up of 30.9 months. Patients with increased flow were 10.2 times more likely to relapse even after correction for other prognostic variables. In addition, tumors with 2 + capsular flow correlated with a higher incidence of non-organ-confined disease. Conclusions Color-coded Doppler flow within the tumor and overlying capsule appears to correlate with both tumor grade and stage, respectively. Detection and grading of color-coded flow within biopsy-proven cancers may identify patients with a high likelihood of biochemical relapse.

Flow cytometry as a predictive modality in prostate cancer

Clinical staging and histologic grading do not have sufficient predictive value to determine the response to therapy of any given prostate cancer. A review of the findings from the largest prospective study of patients with localized and locally advanced prostate cancer and from retrospective flow cytometric studies of specific disease stages suggests that DNA flow cytometry offers additional prognostic information for this disease. However, for the individual patient, this added information may have limited value, since approximately 15% of those with diploid disease will experience disease progression within 5 years as compared with half of those with nondiploid disease. We have found that ploidy does not predict length of survival once prostate cancer becomes disseminated, nor does it predict those who will benefit from receiving definitive radiation therapy for localized prostate cancer. On the other hand, for those who have persistent tumor, we have frequently found increased ploidy abnormalities in the tumor sampled after radiation therapy and are currently correlating this finding with clinical outcome. We have also found that DNA flow cytometry can be used to predict tumor volume. For larger, grade-matched diploid tumors, there are significant increases in the proliferation of both the tumor and the adjacent benign tissue, which we take to be evidence of “field effects” in this disease. An even more obvious manifestation of the same phenomenon is seen in the occurrence of aneuploidy in benign tissue near high-grade, large-volume prostate cancer. It is concluded that DNA flow cytometry has much to tell us about the natural history and biologic behavior of prostate cancer.

Nuclear DNA ploidy and prostate cancer.

Prostate cancer is now the most common cancer in men in the United States [1]. Although 103,000 new cases were expected in 1989, less than one third were projected to die of their disease. The vast majority of prostate cancer remains clinically undetectable for the patient’s entire life. This discrepancy in the biologic behavior of prostate cancer remains a mystery. However, attempting to determine which tumors will remain indolent and which will follow an aggressive course is the work of much investigation.

Endogenous and exogenously-induced immunomodulation of tumour-host responsiveness

In spite of the availability of multiple effector mechanisms of the immune system to combat tumour growth and metastases, their impairment frequently accompanies the appearance of cancer. Factors contributing to this impairment may be related to properties of the host and/or the tumour itself and may be with respect to their origin -endogenous or exogenour. Based on the unique biological behavior of prostate cancer (PCa), and its apparent escape from immune surveillance in the presence of tumour immuno genicity, continuing investigation of endogenous and exogenous factors thought to be relevant to its pathogenesis have been made. For this purpose further studies of the suggested role of human seminal plasma (SePl) and the synthetic oestrogen, diethylstiboestrol (DES), as representative endogenous and exogenous immunomodulatory factors (IMF) of tumour-host responsiveness, together with evaluation of human prostatic tissue extracts and leuprolide (the luteinizing-hormone-releasing-hormone proposed as an alternate to DES therapy) have been made by evaluating their effect on the lytic activity of natural killer (NK) cells. SePl and prostate extracts significantly suppressed NK cell lysis. Physicochemical studies suggest SePl and prostate IMF to be associated with high and low molecular weight macromolecules; and implicate the participation of transglutaminase and prostaglandins. Comparative study of therapeutic levels of DES vs. leuprolide on NK cell lysis demonstrated significant suppression by DES vs. a negligible effect of leuprolide. Metastases are highly prevalent in PCa, and contribute significantly to its morbidity and mortality. Further knowledge of the range of effects of endogenous and exogenous IMF on effector mechanisms of tumour-host responsiveness, to include suppression of NK cells, and elucidation of their nature, may contribute toward our understanding of the unique biological behavior of tumours of the prostate, in addition to improvement in their clinical management.