Severe combined immunodeficient-hu model of human prostate cancer metastasis to human bone.

Commonly used in vivo models of prostate cancer metastasis include syngeneic rodent cancers and xenografts of human cancer in immunodeficient mice. However, the occurrence of osseous metastases in these models is rare, and in xenograft models, species-specific factors may limit the ability of human cells to metastasize to rodent bones. We have modified the severe combined immunodeficient (SCID)-human model to test the ability of circulating human prostate cancer cells to home to macroscopic fragments of human bone and other organs previously implanted into SCID mice. We have also compared the growth of human prostate cancer cells in various human and mouse tissue microenvironments in vivo. Macroscopic fragments of human fetal bone, lung, or intestine (16-22 weeks gestation) or mouse bone were implanted s.c. into male CB.17 SCID mice. Four weeks later, human prostate cancer cells were injected either i.v. via the tail vein (circulating cell colonization assay) or directly into the implanted tissue fragments transdermally (end organ growth assay). Tumor growth was followed for 6 weeks by palpation and magnetic resonance imaging. After 6 weeks, tumors were enumerated in implanted human and mouse organ fragments and native mouse tissue. Tumors were characterized by histology, immunohistochemistry, and chromosomal analysis. After i.v. injection, circulating PC3 cells successfully colonized implanted human bone fragments in 5 of 19 mice. Tumors were easily followed by palpation and imaging and had an average volume of 258 mm3 at autopsy. Histological examination revealed osteolysis and a strong desmoplastic stromal response, which indicated intense stromal-epithelial interaction. Bone tumors were subcultured, and chromosomal analysis demonstrated that the tumors were derived from the parental prostate cancer cell line. Microscopic tumor colonies were also found in a few mouse lungs after i.v. injection of PC3, DU145, and LNCaP cells, however the volume of the lung nodules was less than 1 mm3 in all of the cases. No colonization of human lung or intestine implants, the mouse skeleton, or other mouse organs was detected, demonstrating a species- and tissue-specific colonization of human bone by PC3 cells. Direct injection of 10(4) prostate cancer cells into human bone implants resulted in large tumors in 75-100% of mice. PC3 and DU145 bone tumors were primarily osteolytic, whereas LNCaP bone tumors were both osteoblastic and osteolytic. PC3 and LNCaP bone tumors showed a desmoplastic stromal response, which indicated intense stromal-epithelial interaction. All three of the cell lines formed tumors in implanted human lung tissue; however, the tumors were all < or = 10 mm3 in volume and showed minimal stromal involvement. No tumors formed after either s.c. injection or injection of cells into implanted mouse bone demonstrating both species- and tissue-specific enhancement of growth of human prostate cancer cells by human bone. The severe combined immunodeficient-human model provides a useful system to study species-specific mechanisms involved in the homing of human prostate cancer cells to human bone and the growth of human prostate cancer cells in human bone.

Genetic alterations in untreated metastases and androgen-independent prostate cancer detected by comparative genomic hybridization and allelotyping.

A newly developed method of comparative genomic hybridization (CGH) employing quantitative statistical comparisons was applied to DNA from two different types of advanced prostate cancer tissue. Multiple CGH analyses were obtained for each chromosome in each tumor, and the results of point-by-point comparison of the mean tumor:normal color ratio to a control normal:normal color ratio in each of 1247 evenly distributed data channels constituting the entire human genome were interpreted as loss, gain, or no change in copy number in the tumor genome. Group I tissue was obtained from prostate cancer metastases from 20 patients, 19 of whom had received no prior prostate cancer treatment. This DNA also was analyzed by Southern and microsatellite allelotyping at 53 different loci on 20 different chromosome arms. CGH results agreed with allelotyping results at 92% of the informative loci studied. These samples, which contained highly enriched tumor DNA, showed the highest rates of alteration yet reported in several chromosomal regions known to be altered frequently in prostate cancer: 8q gain (85%), 8p loss (80%), 13q loss (75%), 16q loss (55%), 17p loss (50%), and 10q loss (50%). Group II tissue was obtained predominately from primary or recurrent tumor from 11 patients who had been treated with long-term androgen-deprivation therapy and developed androgen-independent metastatic disease. Quantitative CGH analysis on DNA from these tissues showed chromosomal alterations that were very similar to those found in group I, suggesting that untreated metastatic tumors contain the bulk of chromosomal alterations necessary for recurrence to occur during androgen deprivation. In the entire data set, a number of previously undetected regions of frequent loss or gain were identified, including losses of chromosomes 2q (42%), 5q (39%), 6q (39%), and 15q (39%) and gains of chromosomes 11p (52%), 1q (52%), 3q (52%), and 2p (45%). Chi-squared analysis showed a significantly higher frequency of gain of the 4q25-q28 region in tumors from African-American patients, indicating a possible oncogene whose activation may play a role in the higher rate of progression seen in this ethnic group. Additional study of these frequently altered regions may provide insight into the mechanism of prostate cancer progression and lead to important tools for tumor-specific prognosis and therapy.

Variation in the use of postoperative radiotherapy among high-risk patients following radical prostatectomy.

BACKGROUND: We used data from the Michigan Urological Surgery Improvement Collaborative (MUSIC) to investigate the use of adjuvant and salvage radiotherapy (ART, SRT) among patients with high-risk pathology following radical prostatectomy (RP). METHODS: For patients with pT3a disease or higher and/or positive surgical margins, we examined post-RP radiotherapy administration across MUSIC practices. We excluded patients with <6 months follow-up, and those that failed to achieve a postoperative PSA nadir ⩽0.1. ART was defined as radiation administered within 1 year post RP, with all post-nadir PSA levels <0.1 ng ml(-1). Radiation administered >1 year post RP and/or after a post-nadir PSA ⩾0.1 ng ml(-1) was defined as SRT. We used claims data to externally validate radiation administration. RESULTS: Among 2337 patients undergoing RP, 668 (28.6%) were at high risk of recurrence. Of these, 52 (7.8%) received ART and 56 (8.4%) underwent SRT. Patients receiving ART were younger (P=0.027), more likely to have a greater surgical Gleason sum (P=0.009), higher pathologic stage (P<0.001) and received treatment at the smallest and largest size practices (P=0.011). Utilization of both ART and SRT varied widely across MUSIC practices (P<0.001 and P=0.046, respectively), but practice-level rates of ART and SRT administration were positively correlated (P=0.003) with lower ART practices also utilizing SRT less frequently. Of the 88 patients not receiving ART and experiencing a PSA recurrence ⩾0.2 ng ml(-1), 38 (43.2%) progressed to a PSA ⩾0.5 ng ml(-1) and 20 (22.7%) to a PSA ⩾1.0 ng ml(-1) without receiving prior SRT. There was excellent concordance between registry and claims data κ=0.98 (95% CI: 0.94-1.0). CONCLUSIONS: Utilization of ART and SRT is infrequent and variable across urology practices in Michigan. Although early SRT is an alternative to ART, it is not consistently utilized in the setting of post-RP biochemical recurrence. Quality improvement initiatives focused on current postoperative radiotherapy administration guidelines may yield significant gains for this high-risk population.

Effect of neoadjuvant androgen deprivation on circulating prostate cells in the bone marrow of men undergoing radical prostatectomy.

Our objective was to determine the effect of neoadjuvant hormonal therapy on the presence of circulating prostate cells in patients undergoing radical prostatectomy for prostate cancer. A total of 60 patients at high risk for extraprostatic disease were analyzed for the presence of circulating prostate cells using reverse transcriptase PCR (RTPCR) amplification of the prostate-specific antigen mRNA. Twenty-nine patients underwent radical prostatectomy for a clinical T2b-c tumor or a stage T1c-T2a tumor and a serum prostate-specific antigen level > or =10ng/ml (radical prostatectomy alone), and 31 similarly staged patients received neoadjuvant hormonal therapy before radical prostatectomy (neoadjuvant). Bone marrow samples were used for RTPCR analysis. Twenty-four percent and 58% of the radical-prostatectomy-alone patients and neoadjuvant patients had organ-confined disease, respectively (P = 0.007). In the radical-prostatectomy-alone group, 77% and 14% of patients with extraprostatic and organ-confined disease were RTPCR positive, respectively (P = 0.03). However, in the neoadjuvant group, 46% and 28% of patients with extraprostatic and organ-confined disease were RTPCR positive, respectively (P = 0.29). For patients that were RTPCR positive, 45 % of the neoadjuvant patients had organ-confined disease compared with 6% in the radical-prostatectomy-alone patients (P = 0.018). These data suggest that a subset of the neoadjuvant patients are converted to organ confined disease without eliminating the prostate cells in the bone marrow. Our data suggest that hormonal therapy before radical prostatectomy decreases the occurrence of extraprostatic disease but, to a lesser degree, the incidence of circulating prostate cells. This may partially explain why hormonal therapy before radical prostatectomy has not improved disease-free survival.

A similar pattern of chromosomal alterations in prostate cancers from African-Americans and Caucasian Americans.

A combination of genetic and epigenetic factors may explain the disproportionate incidence and mortality of prostate cancer among African-American males (AAMs) as compared with Caucasian American males (CAMs). We wished to determine whether primary prostate cancers from AAMs and CAMs harbor different patterns or frequencies of chromosomal alterations. Comparative genomic hybridization (CGH) was performed on clinically localized, untreated primary prostate cancers from 16 AAMs and 16 CAMs. Detailed statistical analysis was used to delineate gains and deletions with high sensitivity and specificity and to compare the frequency and pattern of alterations between the two groups of tumors. The two groups of patients had indistinguishable preoperative serum prostate-specific antigen levels, and the two groups of tumors had similar pathological stages and grades. Chromosomal gains and deletions occurred in regions known to be frequently altered in prostate cancer. Specifically, the most frequent alterations were deletions of regions on chromosomes 13q, 5q, 16q, and 8p and gains of regions on 8q and 5q. When tumors from AAMs and CAMs were compared, the frequencies of alteration (deletion, gain, or no alteration) were similar across 98.9% of the length of the genome. The patterns of alterations of the most frequently altered chromosomes were also similar between tumors from AAMs and CAMs. We concluded that primary prostate cancers from AAMs and CAMs harbor a similar pattern and frequency of chromosomal alterations. These data support the notion that sporadic prostate cancers from AAMs and CAMs develop by similar chromosomal mechanisms. Biological differences, if present, do not occur on the chromosomal level.

Cellular proliferation and prevalence of micrometastatic cells in the bone marrow of patients with clinically localized prostate cancer.

The presence of prostate cancer cells in the bone marrow (BM) of patients with clinically localized disease is associated with an increased chance of disease recurrence; however, not all patients develop recurrence. We therefore sought to determine the phenotype of individual micrometastatic cells as a potential method to better predict disease outcome. Immunostaining was performed on BM cells from 46 patients whose BM RNA fraction had been identified to contain prostate-specific antigen mRNA. The prevalence of micrometastatic cells among BM mononuclear cells was determined using an anticytokeratin antibody. Mib-1 antibody was used to determine the percentage of micrometastatic cells that were proliferating. Micrometastatic cells were found in 96% of patient samples, with a 30-fold variation in prevalence ranging from 0.1-3.26/10(5) BM cells. Prior androgen ablation was associated with a reduced prevalence of micrometastatic cells (P = 0.010). In 68% of patients, some micrometastatic cells were judged to be proliferating at proportions ranging from 1 of 11 (9%) to 4 of 4 (100%). Higher Gleason score of the primary tumor was associated with a higher proliferative proportion of micrometastatic cells (P = 0.038). We conclude that, in patients with clinically localized disease, there is wide variability in the prevalence of micrometastatic cells and the proportion which are proliferating. Long-term follow-up will determine whether the development of clinically obvious metastatic disease is related to higher prevalence of micrometastatic cells in the marrow or the proportion that are proliferating.

Systemic interleukin 2 therapy for human prostate tumors in a nude mouse model.

Once the regional lymph nodes become involved in prostate carcinoma, 85% of patients develop distant metastases within 5 years, and metastatic disease is difficult to treat. We have investigated the effect of systemic interleukin 2 (IL-2) treatment on metastatic prostate carcinoma using a xenograft tumor model. Cells from a PC-3/IF cell line, produced by intrafemoral injection of human PC-3 prostate carcinoma cells, were injected in the prostate of Balb/c nude mice. Prostate tumors and para-aortic lymph nodes were resected, and tumor cells were recultured and passaged in the prostate in vivo to produce new cell lines. On day 6 following prostatic injection of these cell lines, mice were treated with i.p. injections of IL-2 at 25,000-50,000 units/ day for 5 consecutive days. The effect of IL-2 on tumor progression was assessed, and histological studies were performed on prostate tumor and lymph node sections. The tumor cell lines generated by serial prostate injection were tumorigenic and metastasized to regional para-aortic lymph nodes. Tumors of 0.4 cm were obtained by day 16 and grew to 1-1.5 cm by day 40 with metastasis to para-aortic lymph nodes. Following two to three weekly courses of 5 days of 25,000-40,000 units/day of IL-2, the growth of prostate tumors was inhibited by 94%. Higher doses of 50,000 units/ day were toxic. Histologically, prostate sections showed vascular damage manifested by multifocal hemorrhages and an influx of lymphocytes and polymorphonuclear cells into disintegrating tumors and areas of necrosis containing numerous apoptotic cells. In contrast to control mice, para-aortic lymph nodes were not enlarged in responding mice. These findings suggest that systemic IL-2 therapy can induce an antitumor response in prostate tumors and control their growth and metastasis.

Membrane type 1-matrix metalloproteinase (MT1-MMP) and MMP-2 immunolocalization in human prostate: change in cellular localization associated with high-grade prostatic intraepithelial neoplasia.

Membrane type 1-matrix metalloproteinase (MT1-MMP) is a known activator of latent MMP-2 (pro-MMP-2), and increased MMP-2 expression has been associated with tumor aggressiveness in prostate cancer. However, expression of MT1-MMP in human prostate tissue has not been described. We investigated the expression and immunolocalization of MT1-MMP and MMP-2 in the epithelial components of benign prostate epithelium, high-grade prostatic intraepithelial neoplasia (HGPIN), and prostate cancer. Tissue sections from the peripheral zone of 50 prostates (radical prostatectomy specimens) were chosen based on their containing benign glands, HGPIN, and prostate cancer glands. All 50 sections were immunostained for MT1-MMP and MMP-2 and were evaluated for staining pattern, uniformity, and intensity. Western blotting and gelatin zymography were done to confirm expression of MT1-MMP and activity of MMP-2, respectively. Comparisons were made between benign epithelium, HGPIN, and cancer. In benign glands, basal cells (BCs) uniformly stained intensely for MT1-MMP, whereas secretory cells (SCs) were rarely positive (P < 0.0001). Conversely in HGPIN, SCs showed consistent cytoplasmic staining (P < 0.0001). In cancer cells, staining was heterogeneous and varied from no staining to very intense staining in select glands. MMP-2 in normal tissue stained both BCs and the apical region of SCs, whereas in HGPIN, staining was observed in the SC in a predominantly cytoplasmic pattern. Similar to MT1-MMP, staining in cancer tissue for MMP-2 was heterogeneous; however, there was a significant association between the pattern of MMP-2 and MT1-MMP staining within the epithelial components of the cancer glands in individual specimens (P < 0.001). Finally, MMP-2 and MT1-MMP were confirmed to be expressed in the prostate tissues by gelatin zymography and Western blotting. In conclusion, we found that consistent changes in localization and intracellular distribution of MMP-2 and MT1-MMP were associated with the transition from benign prostate epithelium to HGPIN, suggesting that regulation of these enzymes is altered during the earliest stages of prostate cancer.

Persistence of human vascular endothelium in experimental human prostate cancer bone tumors.

Using the SCID-human model, we recently found that human circulating prostate cancer cells formed tumors in human bone but not mouse bone (Nemeth et al. Cancer Res 1999; 59: 1987-93). It is possible that this tissue preference was mediated by interaction between human tumor cells and human endothelial cells within the implanted bone tissue. We sought to determine the relative amounts of human and mouse vasculature within human bone implants and resulting prostate cancer bone tumors in the SCID-human model. Paraffin sections of plain bone implants or PC3 or LNCaP human bone tumors were double stained for factor VIII (all vessels) and human CD31 (human vessels) followed by fluorescent secondary reagents. At 4 weeks post implantation (when cancer cells are typically introduced), the vasculature within human bone fragments remained primarily human (84.5%), and this pattern persisted to at least 10 weeks (91.6% human). Injection of PC3 cells into the bone resulted in an increase in mouse-derived vessels, however the majority (58%) of the vessels remained human even after the formation of large bone tumors. LNCaP bone tumors were highly angiogenic, and there was a sharp decline in the proportion of vessels which were antigenically human (36.8%), suggesting recruitment of mouse endothelial cells during the angiogenic process. Nonetheless, the persistence of human vasculature suggests the SCID-human model can be used to study the interaction between bone-seeking tumor cells, such as prostate cancer, and human bone endothelium in vivo, and to test potential therapeutic strategies which may depend on the presence of human vessels.

Identification of genetic alterations associated with the process of human experimental colon cancer liver metastasis in the nude mouse.

Understanding the genetic elements controlling the process of tumor metastasis to distant organ sites such as the liver may be the key to improving survivorship from colon cancer. By using standard cytogenetic techniques in combination with comparative genomic hybridization, multiple genetic imbalances within three human colon cancer cell lines previously selected for differences in liver-metastatic behavior were identified. The entire genome of one poorly metastatic cell line (KM12C) was compared directly with that of two highly metastatic cell lines (KM12SM, KM12L4A) derived from it. A number of chromosomal gains (8q, 12q15, 20q11.2) and losses (5p13, 6p21.3, 18) were common to all three cell lines and are likely related to early tumor development rather than to the selection process used to generate cell lines of increased metastatic potential. Chromosomal imbalances detected only in the highly metastatic cell lines were also observed. KM12SM showed losses of portions of 2p22, 2q24.3--> 2q32.2, 4p15.3--> cen, 4q24 without the 13q and 15q22.3 gains noted for KM12C. Both gains (1p31.3--> 1p21, 2q22--> 2q33, 3cen--> 3q26.2, 5q14--> 5q23, 6cen--> 6q23) and losses (16p, 17p, 17q 19p, 19q 22q) were observed for KM12L4A but not for the other two cell lines. Identification of these alterations provides valuable insight into the process of experimental liver metastasis and is a first step towards mapping genes linked to the terminal phases of human colon cancer progression.

Chromosomal analysis of renal angiomyolipoma by comparative genomic hybridization: evidence for clonal origin.

Angiomyolipoma has long been considered a hamartomatous polyclonal proliferation. However, recent molecular analyses have indicated that these tumors may be clonal neoplasms rather than polyclonal proliferations. We investigated chromosomal imbalances in angiomyolipoma by comparative genomic hybridization. DNA was extracted from archival paraffin-embedded and frozen tissues of 12 angiomyolipomas (10 usual variant, two epithelioid variant). The 10 angiomyolipomas of the usual variant included bilateral tumors from one tuberous sclerosis patient. Fluorescence ratio distributions from tumor hybridizations were compared with those from control hybridizations to detect changes in DNA copy number with high sensitivity and specificity. We identified 20 chromosomal imbalances in seven sporadic angiomyolipomas, including both tumors of the epithelioid variant. The remaining five tumors, including the two angiomyolipomas from a tuberous sclerosis patient, were devoid of chromosomal imbalances. Seventy-five percent of the imbalances were partial or whole chromosomal deletions involving disparate genomic regions, some of which have previously been associated with tumors of adipose tissue and smooth muscle tumors. Four angiomyolipomas of the usual variant showed 5q deletions with a common region of deletion spanning 5q33 to q34. In two tumors, deletion on 5q was the sole abnormality. One epithelioid angiomyolipoma showed 5q gain encompassing the same region in addition to other alterations. We concluded that (1) Chromosomal imbalances are common in renal angiomyolipomas; (2) Presence of clonal genomic alterations lends further support to the neoplastic pathogenesis of these tumors; (3) The 5q33-q34 region may contain a tumor suppressor gene significant in the histogenesis of some renal angiomyolipomas.

Allelic imbalance mapping of chromosome 16 shows two regions of common deletion in prostate adenocarcinoma.

Allelic imbalance (AI) has now been reported on the long arm of chromosome 16 in several cancers including breast, prostate, hepatocellular carcinoma, and Wilms tumor. Such nonrandom AI is commonly associated with the presence of a tumor suppressor gene (TSG) at or near the tested locus. Previous studies in our laboratory indicated that prostate cancer genomes frequently exhibit a region of allelic loss near the q terminus of chromosome 16. Here we report a detailed, PCR based, allelic imbalance study at ten polymorphic loci on 16q. The data indicate that there are two common regions of 16q AI in prostate cancer, one at 16q21-22 (50% of informative cases) and another at 16q24.2-qter (56% of informative cases). These are similar to regions of 16q previously shown to exhibit AI in breast cancer. Neither of these regions shows correlation of AI with the clinical parameters; Gleason grade, tumor stage, or metastases.

Stepwise genetic changes associated with progression of nontumorigenic HPV-18 immortalized human prostate cancer-derived cell line to a malignant phenotype.

Cytogenetics, fluorescence in situ hybridization (FISH), and comparative genomic hybridization (CGH) were used to identify genes that are involved in the development and progression of prostate cancer. For that purpose, we chose a cell line established in vitro from a prostatic adenocarcinoma which was nontumorigenic in nude mice and followed its progression to a tumorigenic cell line. Stepwise changes were observed in the cell line as it became tumorigenic. The composite karyotype at the nontumorigenic stage (CA-HPV-10) was 68 approximately 77,XXY,-(1, 9, 13, 14, 19, 22),+(4, 5, 11, 18, 20, 21),+(del(1) (q23q31)=M1 (two copies), +der(9)t(1;9)(q24 approximately q31;p23)=M5(two copies), der(14)t(14;?)(q10;?)=M17 in the majority of metaphases. These two derivative chromosomes were also observed a previous study. Our CGH analysis clearly showed that this deleted region in M1 is, in fact, translocated with derivative M5 and, in reality, is amplified. The cell line established from nodule (SCID 5019 p11), showed a number of new changes, as described; however, the most significant change was amplification of the 8q23 approximately qter region, harboring c-myc. This region was translocated with chromosomes 2, 4, and 16 as der(2)t(2;8)(q33;q23)=M12, der(4)t(4;8)(q34;q23)=M11, and der(16)t(8;16)(q24;q21)=M9. We deduce from our study that amplification of c-myc and other genes in the 8q23 approximately qter region were important in progression but did not lead to tumorigenicity. The population that became tumorigenic (SCID 5019 II) showed almost all of the same changes in the karyotype as observed in the nodular cell line; the only significant change was the appearance of der(11)t(4;11)(q32;q22)=M7 and the addition of another copy of t(3q;7p)=M2. These new changes lead to loss of chromosomes 3p, 4pter approximately q34, 6, 7q21 approximately qter, 11q22 approximately qter, and 18q, and gain of 3q, 7p, 8q23 approximately qter, and 11pter approximately q22, before the cell line became tumorigenic. The clonal selection of the population is proven by the presence of a number of the same derivative chromosomes in both the nodular and tumorigenic cell line. As it progressed to tumorigenicity, some of the same changes observed in the original study re-appear at different stages of malignancy, although it was absent in the nontumorigenic cell line. These are: der(16)t(8;16)(q24;q21)=M9 in the nodular cell line and der(11)t(4;11)(q32;q22)=M7 in the tumorigenic cell line. In our system, amplification of c-myc and other genes in der(2)t(2;8)(q33;q23)=M12,der(4) t(4;8)(q34;q23)=M11 together with the presence of der(16)t(8;16)(q24;q21)=M9 and der(11)t(4;11)(q32;q22)=M5 makes the cell line tumorigenic. It is either nontumorigenic, with the presence of a marker equivalent to der(16)=M9 and der(11)=M7 observed in the original study, and only nodular (SCID 5019 p11, present study), with the presence of number of markers with c-myc amplification (M9, M11, and M12). There is accumulation of all the above-mentioned changes in the same cell before it becomes tumorigenic.

Predictors for maximal outcome in patients undergoing salvage surgery for radio-recurrent prostate cancer.

OBJECTIVES: To determine preradiation and preoperative clinical staging and postoperative pathologic factors that can predict disease-free survival in patients undergoing salvage surgery for radio-recurrent prostate cancer. METHODS: A retrospective review was performed on 40 patients who underwent salvage surgery for radio-recurrent prostate cancer. Preradiation and preoperative clinical staging factors, as well as pathologic stage were analyzed as predictors of disease-free survival. Biochemical failure was defined as a persistent serum prostate-specific antigen (PSA) elevation greater than 0.4 ng/mL. RESULTS: As a group, salvage surgery provided excellent clinical disease control in 35 of 40 patients (87.5%). Overall, 18 of 38 (47.4%) patients analyzed had no evidence of biochemical progression. Preradiation clinical stage and pathologically organ-confined disease were statistically significant predictors of disease-free survival (P = 0.03 and P = 0.02, respectively). Seminal vesicle invasion and positive lymph nodes were the worst pathologic prognostic factors. Preoperative clinical T1c disease approached statistical significance in predicting pathologically organ-confined disease and disease-free survival (P = 0.08 and P = 0.07, respectively). CONCLUSIONS: Ideal candidates for salvage surgery should have preradiation and preoperative clinically organ-confined disease. All patients with pathologically organ-confined disease following salvage prostatectomy were disease free at a mean follow-up of 36.1 months. Salvage surgery, although technically feasible, should not be widely advocated as an effective curative treatment in patients with locally advanced disease at the time of diagnosis.

Prostate cancer old problems and new approaches : Part I. epidemiology, incidence and genetic alterations.

Rates of prostate cancer (PCa) have increased so dramatically over the last decade that the age adjusted incidence rate for PCa is now greater than that any other cancer among men in the United States. This review, published as a three part series, provides a state-of-art assessment of the PCa problem in its divergent aspects.Part 1 covers epidemiology, incidence and progression. Several epidemiological studies have demostrated that first degree male relatives of men with PCa are at increased risk of developing the disease. Familial and genetic factors as well as medical, anthropometric, dietary, hormonal and occupational factors involved in PCa are discussed. Postmortem examination of the prostate in men without evidence of PCa documented a high frequency of adenocarcinoma. Latent disease occurred as early as the second decade of life. Although there is no significant difference in incidence between Caucasian and African-American males, high grade prostatic intraepithelial neoplasia (HGPIN) is higher in the latter group. While dietary fat, androgens and certain environmental factors may be determinants for PCa, the exact mechanism of tumorigenesis is still relatively unknown. The current thinking of the role of genomic instability, chromosomal alterations, tumor suppressor genes and the androgen receptor are explored.

A novel function for platelet-derived growth factor D: induction of osteoclastic differentiation for intraosseous tumor growth.

Although increasing evidence suggests a critical role for platelet-derived growth factor (PDGF) receptor ß (ß-PDGFR) signaling in prostate cancer (PCa) progression, the precise roles of ß-PDGFR and PDGF isoform-specific cell signaling have not been delineated. Recently, we identified the PDGF-D isoform as a ligand for ß-PDGFR in PCa and showed that PDGF-D is activated by serine protease-mediated proteolytic removal of the CUB domain in a two-step process, yielding first a hemidimer (HD) and then a growth factor domain dimer. Herein, we demonstrate that the expression of PDGF-D in human PCa LNCaP cells leads to enhanced bone tumor growth and bone responses in immunodeficient mice. Histopathological analyses of bone tumors generated by PDGF-D-expressing LNCaP cells (LNCaP-PDGF-D) revealed osteolytic and osteoblastic responses similar to those observed in human PCa bone metastases. Importantly, we discovered a novel function of PDGF-D in the regulation of osteoclast differentiation, independent of the RANKL/RANK signaling axis. Although both PDGF-B and -D were able to activate ß-PDGFR, only PDGF-D was able to induce osteoclastic differentiation in vitro, and upregulate the expression and nuclear translocation of nuclear factor of activated T cells 1, a master transcription factor for osteoclastogenesis. Taken together, these results reveal a new function of PDGF-D as a regulator of osteoclastic differentiation, an activity critical for the establishment of skeletal metastatic deposit in PCa patients.

Mechanisms governing bone metastasis in prostate cancer.

Why does prostate cancer metastasize to bone? Why is there increased turnover of the bone matrix in the presence of prostate cancer? A recent autopsy study supports a traditional hypothesis that gross, anatomic patterns of blood flow influence the distribution of metastatic deposits. On the other hand, recent developments in animal models of prostate cancer bone metastasis have renewed interest in the traditional 'seed and soil' hypothesis: several studies point to specific biological interactions between prostate cancer cells and the bone microenvironment that can explain the tendency of prostate cancer cells to colonize bone and grow into clinically relevant metastatic deposits. Some studies implicate mechanisms including chemoattraction and enhanced adherence to bone endothelium. Additional data suggest that prostate cancer cells are 'osteomimetic', that is, they take on the properties and behaviors of osteoblasts or osteoclasts upon arrival in bone. These activities lead to enhanced turnover of the bone matrix and may explain the propensity of prostate cancer to grow in bone. Finally, a series of studies have implicated other molecular markers as distinguishing characteristics of bone-metastatic prostate cancer tissue.

Continence in the myelodysplastic patient following enterocystoplasty.

To evaluate the ability of augmentation cystoplasty alone to provide a low pressure bladder and an adequate degree of continence in the myelodysplastic patient, the clinical records and urodynamic data of the last 18 consecutive such patients undergoing augmentation cytoplasty at our institution were reviewed. Two patients underwent colocystoplasty and 16 underwent ileocystoplasty. No patient underwent any procedure on the bladder neck or urethra. The 2 colocystoplasty patients exhibited episodic dampness attributed to contractions of the augmentation but all of the ileocystoplasty patients were dry during the day except 1 who had a urethral resistance of only 19 to 22 cm. water. On the basis of this review, ileocystoplasty alone appears to be sufficient for satisfactory continence in patients with a neurogenic bladder undergoing vesical augmentation if bladder outlet resistance exceeds 25 to 30 cm. water.