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Background: Maspin, a novel serine protease inhibitor, has been shown to inhibit prostate tumor cell motility and invasion in vitro and to inhibit prostate tumor growth and metastasis in vivo. Maspin expression in high-grade prostate carcinoma (PC) is reduced compared with that in low-grade PC. Interestingly, however, compared with low-grade PC, benign secretory prostate epithelial cells express significantly less maspin. This observation appears paradoxical to a putative tumor suppressive role of maspin in prostate carcinogenesis, and this finding issue needs to be clarified., Methods: We examined maspin expression simultaneously in benign basal cells, benign secretory cells, high-grade prostate intraepithelial neoplasia (HGPIN), low-grade PC, and high-grade PC in 46 radical prostatectomy specimens plus 51 autopsy prostate glands by a combination of immunohistochemistry and in situ hybridization., Results: Benign basal cells consistently expressed maspin at a high level. In PC, the loss of basolateral maspin expression coincides with loss of the basal cell layer. Maspin expression in secretory cells, on the other hand, appears to undergo a biphasic differential regulation, i.e., essentially absent in benign secretory cells, dramatically up-regulated in HGPIN, then progressively down-regulated through low-grade PC to high-grade PC. Maspin expression in PC is inversely correlated with tumor grade. Furthermore, maspin expression in HGPIN is inversely correlated with the Gleason's grade of the adjacent PC., Conclusions: An up-regulation of maspin expression precedes, rather than occurs at, the critical transition from premalignant prostate lesion of HGPIN to PC. Our data suggest maspin may mark an important transitional phase and play an important role in the premalignancy of the prostate gland., (Copyright 2002 Wiley-Liss, Inc.)

Objective: Due to the significant impact on prognosis by subgrouping of prostatectomy Gleason scores < 7, 7, and > 7, we undertook this study to answer whether the biopsy Gleason score was as predictive of disease free survival and assess the correlation with the prostatectomy Gleason score in a modern prostatectomy series., Methods: An analysis of 1,031 patients who underwent radical prostatectomy for clinically localized prostate cancer was performed. All data was prospectively collected. The Gleason score was categorized into 3 different groups (< 7, 7, and > 7) for biopsy and prostatectomy specimens. Disease free survival was then analyzed for each group. Discrepancies between scores and outcomes were evaluated., Results: Accurate correlation was noted in 54.8, 66.8, and 47.4% of Gleason scores < 7, 7, and > 7, respectively. Overall accuracy was 58.3%. Both, biopsy and prostatectomy Gleason score correlated significantly with disease free survival (P = 0.001), furthermore the classification (Gleason scores < 7, 7 and > 7) was highly significant (P = 0.001). Patients with prostatectomy Gleason < 7 tumors had significant survival advantage over those with biopsy Gleason < 7, (P = 0.001). However, disease free survival was superior for patients with biopsy Gleason > 7 than those with prostatectomy Gleason > 7, (P = 0.02). The overall disease free survival was similar among the patients with Gleason score of 7 (P = 0.12)., Conclusions: It appears that biopsy Gleason score, although oftentimes not correlating strongly with the prostatectomy Gleason score, is an important prognostic factor in prostate cancer. There are significant differences in disease free survival between biopsy and prostatectomy Gleason score categories., (Copyright 2001 Wiley-Liss, Inc.)

Background: In advanced prostate cancer, loss of chromosomal regions on 8p is frequently associated with gain of 8q. We studied the gross chromosomal abnormalities associated with 8p loss of heterozygosity (LOH) in the prostate tumor cell line 1542 CP3Tx. The cell line was previously established from a primary prostatic adenocarcinoma by immortalization with a recombinant retrovirus carrying the E6 and E7 genes of human papilloma virus type 16. Allelotyping studies demonstrated LOH at multiple markers on 8p., Methods: To investigate the relationship of 8p LOH to gross chromosomal rearrangements, and to screen for other genetic abnormalities in 1542 CP3Tx, we used comparative genomic hybridization (CGH), conventional karyotyping, fluorescence in situ hybridization (FISH), and allelotyping., Results: CGH revealed loss of the entire 8p arm, associated with gain of the entire 8q arm. Other abnormalities included chromosome 4 loss and chromosome 11 gain. The karyotype showed an isochromosome (8q), monosomy 4, and trisomy 11. FISH and allelotyping confirmed and extended these results., Conclusions: These results demonstrate that i(8q) formation is a mechanism for associated 8p loss and 8q gain in prostate cancer. Furthermore, the small number of chromosomal abnormalities in this cell line indicates that immortalization of low-passage cultures with viral oncogenes provides a method for obtaining cell lines for studying genetic abnormalities in prostate cancer., (Copyright 1999 Wiley-Liss, Inc.)

Background: The p21(WAF1) gene is considered to be one of the major regulators of the cell cycle. Its level of expression has been shown to correlate with pathologic stage and Gleason score in prostatic cancer. However, its relationship to clinical outcome is not yet well-characterized., Methods: Immunohistochemical staining for p21(WAF1) protein expression was performed in 62 consecutive radical prostatectomy specimens from our institution. The results were correlated with the disease-free survival and biochemical recurrence of the patients., Results: Thirty-four of the 62 patients were Caucasian and 28 were African American. There was a significant correlation between p21(WAF1) expression and biochemical recurrence after radical prostatectomy (P < 0.0095). However, while p21(WAF1) staining in prostate cancer was a prognostic indicator of disease-free survival in Caucasians (P < 0.0001), it appeared not to be a factor in African-American men (P = 0.908)., Conclusions: This study suggests that p21(WAF1) may have a role in the pathogenesis and progression of prostate carcinoma, and may serve as a predictor of biochemical recurrence of this tumor. The differences in the values of p21(WAF1) as a prognostic marker of disease-free survival in Caucasians vs. African Americans suggest that progression of prostate cancer may have different mechanisms in different ethnic groups., (Copyright 1999 Wiley-Liss, Inc.)

Background: We previously reported that African-American men (AAM) have tumors located in the anterior compartment more often than American Caucasian men (ACM) in radical prostatectomy specimens [Tiguert et al.: Prostate 37:230-235, 1998]. In this study, we evaluated the distribution of glandular tissue in the anterior compartment of normal prostate specimens, with specific attention to the anterior fibromuscular area, in order to determine the frequency and origin of glands in this region., Methods: We analyzed 94 prostatectomy specimens obtained from autopsied men between ages 20-30 years. Men in this age group were chosen because few pathological changes are present in the prostate in this age range. The anterior compartment of the prostate was defined by drawing a horizontal line, anterior to the urethra, through the midpoint of the anterior-posterior diameter parallel to the rectal surface. In each slide, anterior compartment prostatic tissue was identified and characterized as peripheral zone, transitional zone, and fibromuscular stroma. Any glandular elements identified in the anterior prostatic compartment were recorded in terms of zonal origin and number of glands., Results: Prostates from 76 AAM and 18 ACM were examined. Overall, prostatic glands were absent in the anterior compartment in only 2% of cases. Glands were derived from the peripheral zone only in 6 (6.5%) cases, peripheral zone and transitional zone in 53 (56.5%), transitional zone only in 13 (14%), and anterior fibromuscular stroma in 20 (21%). There was no difference between the two races in terms of the number of glands present. The morphology of the peripheral zone was not different between the two races, with glands from the peripheral zone joining in the anterior compartment in 33% of AAM compared to 56% of ACM (P = 0.123)., Conclusions: Anterior prostatic glands can arise from the peripheral zone, transitional zone, or fibromuscular stroma. There are no racial differences in terms of the number of anterior glandular elements, and also in the architecture of the peripheral zone.

Background: The routine use of serum prostate-specific antigen (PSA) testing combined with digital rectal examination has lowered tumor volume and clinical-pathological stage of men undergoing radical prostatectomy. Therefore, we may identify more men with poorly differentiated tumors of early clinical stage. In order to identify those who may benefit from radical prostatectomy, we evaluated known prognostic variables in patients with prostate cancer of high Gleason score (8-10)., Methods: Of 652 patients who underwent a radical prostatectomy as monotherapy for clinically localized prostate cancer between March 1991-December 1995, 84 patients with prostatectomy specimen Gleason score 8-10 tumors were identified. Clinical-pathological data were obtained from our prostate cancer database. Gleason score, PSA level, margin status, pathologic stage, and tumor volume were analyzed as general prognostic variables for disease-free survival (DFS). Follow-up ranged from 13-84 months (median, 36.2). Biochemical recurrence was defined as a postoperative PSA elevation greater than 0.4 ng/ml., Results: The DFS for patients with Gleason score 8-10 and pathologically organ-confined disease was 62.5%. DFS was 56.2% for patients with PSA < or =10 ng/ml, compared to 19.2% for patients with serum PSA >10 ng/ml (P = 0.009). Patients with nonspecimen-confined disease (positive margins) had a DFS rate of 26.6% vs. 55% for patients with specimen-confined disease (negative margins) (P = 0.009). On multivariable analysis, only preoperative PSA < or =10 ng/ml (P = 0.02) and surgical margin status (P = 0.04) were significant predictors of DFS., Conclusions: Surgical margin status and preoperative serum PSA level are independent predictors of DFS for patients with high Gleason score prostate cancer treated by radical prostatectomy as monotherapy. Patients with poorly differentiated prostate cancer treated surgically at an early stage can have a favorable prognosis, especially if negative surgical margins are obtained. A preoperative serum PSA level < or =10 ng/ml carries the greatest likelihood of achieving prolonged DFS in this group of patients.

Background: Our objective was to evaluate radical prostatectomy specimens for possible racial differences in tumor location, as well as to correlate tumor location with pathologic stage and disease-free survival., Methods: Between January 1991-December 1997, 1,245 patients underwent radical prostatectomy with bilateral pelvic lymphadenectomy for clinically localized prostate cancer. Seven hundred and eighty-five patients who were treated with surgery as monotherapy were evaluated. Tumor location, defined as mainly anterior, mainly posterior, or both (anterior and posterior), was obtained from review of tumor maps prepared from pathological evaluation of completely embedded, resected specimens., Results: Overall tumor location was anterior in 107 (14%), posterior in 459 (58%), and both in 219 (28%) cases. The incidence of anterior tumors was higher in African American men compared to Caucasians (16% vs. 11%, P = 0.045). The rate of positive surgical margins in anteriorly and posteriorly located tumors was 60% vs. 38% in African American men (P = 0.001) and 48% vs. 27% in Caucasians (P = 0.001), respectively. African American men were found to have a higher incidence of positive surgical margins (50%; 174/348) compared to Caucasian men (34%; 150/437; P = 0.001)., Conclusions: Anterior tumors were present in 14% of our patients. African American men have a greater percentage of anterior tumors than do Caucasians. In addition, a higher rate of positive surgical margins was encountered in patients with anterior tumors, especially if they were African American men. In patients with an abnormal serum prostate-specific antigen level and negative sextant prostate biopsies, we recommend biopsy of the anterior zone of the prostate.

This study hypothesized that human papillomavirus (HPV) infection is associated with increased prostate cancer risk, and that the 40% higher incidence rate in blacks is attributable to a greater prevalence of oncogenic viral DNA in prostatic tissues. Viral L1 and E6 gene sequences were polymerase chain reaction (PCR) amplified in archival tissues from 56 prostate cancer cases and 42 hyperplastic controls. L1 amplimers were hybridized by dot blot to HPV L1 generic probes, as were E6 amplimers to E6 probes specific for HPV 6, 11, 16, 18, 31, 33, and 45. 12.5% of cases and 9.5% of controls were HPV positive by L1 hybridization (age/race adjusted odds ratio = 1.66, 95% confidence interval = 0.33, 8.37). Four of 52 (7.7%) blacks were HPV positive compared to 7 of 46 (15.2%) whites. However, none of the L1-positive samples hybridized to the E6 type-specific probes, and positive results were not replicable using a broader spectrum of PCR primers and probes. These data suggest that HPV infection is not a significant risk factor for prostate cancer and does not explain the excess cancer risk in blacks.

In order to more clearly define the status of epidermal growth factor receptor (EGFR) in prostate cancer, expression of EGFR transcript and protein was analyzed in paired samples of benign and malignant tissues from 30 radical prostatectomy specimens. Prostate tumors and high grade prostatic intraepithelial neoplasias (PINs) expressed significantly less EGFR protein than benign tissues or low grade PINs (P < 0.001). Expression of EGFR mRNA was analyzed in a subset of the same samples, and was higher in more prostate tumors than benign specimens (P < 0.05). However, differences in mean mRNA expression between malignant and benign tissues were not significant. EGFR mRNA was expressed at moderate or low levels in equivalent numbers of PIN lesions. These results suggest that, although EGFR mRNA expression is somewhat elevated in prostate tumors, EGFR protein expression may be down-regulated in the same malignant tissues. Furthermore, our data demonstrate phenotypic similarity between prostate tumors and high grade PIN at the level of EGFR protein expression.

The relation of prostatic intraepithelial neoplasia (PIN) or ductal dysplasia and the development of invasive prostate cancer is not clear. PIN, especially high grade, is usually associated with coexisting invasive cancer. Although some investigators have identified micro foci of invasive cancer evolving from PIN, the two are usually anatomically separated. Because of these distinct anatomic patterns, many investigators have concluded that PIN represents a "field effect" or marker of potential cancer progression, and is not directly involved in or leads to the development of invasive prostate cancer. We measured the DNA content in 49 foci of invasive cancer and 87 foci of PIN identified in 34 radical prostatectomies containing both PIN and invasive cancer. In addition, we examined 13 prostatectomies and 5 TUR specimens containing only PIN. We found that the majority of low grade PIN had normal or diploid range DNA and that approximately half of the high grade PIN were abnormal or aneuploid. Prostates with coexisting diploid range PIN and invasive cancer had an approximately equal number of diploid range and aneuploid invasive cancers. Conversely, almost all of the aneuploid PIN (usually high grade) had coexisting aneuploid invasive cancers. This would support the hypothesis that events in the progression of prostate cancer may be operative in both the development of PIN and invasive cancer.

Human papillomavirus (HPV) infections are strongly linked to the pathogenesis of uterine cervical neoplasms, and have been implicated in other cancers of the female genital tract. In contrast, the association of HPV with the cancers of the male urogenital tract is less evident, except in anal and penile cancers. However, recent studies reporting the prevalence of HPV infections in human prostate cancers (60-100% HPV 16 positive vs. no infection of HPV) have raised controversies regarding the prevalence of HPV in benign and neoplastic human prostate. We investigated the prevalence of HPV infections in prostatic intraepithelial neoplasia (PIN) and prostatic adenocarcinomas in 23 surgically resected prostates. Polymerase chain reaction (PCR) was used to amplify HPV 6b/11, 16, and 18 specific DNA sequences, using type specific HPV primers selected from the transforming gene E6-E7. The areas of PIN and cancer in 6 microns H&E stained tissue sections were identified, and respective areas of PIN and cancer were isolated from the adjacent serial sections and used for DNA amplification and HPV detection (Fig. 1). Our results demonstrated the presence of HPV 16 in three carcinomas (13%), using type specific primers in PCR amplified samples. We were not able to demonstrate the presence of other HPV types (HPV 6b/11 or HPV 18) in any of the samples using specific primers. Two of these prostates showed relatively strong positive signals by dot blot analysis, when hybridized with a 32P-labeled HPV 16 type specific oligonucleotide probe. One more sample showed weak positivity, when hybridized with a 32P-labeled HPV 16 type specific oligonucleotide probe. Subsequently, we have confirmed these results by Southern hybridization of the samples transferred to nylon membrane after agarose gel electrophoresis and detected by HPV 16 type specific oligonucleotide probe, using chemiluminescent assay. We, therefore, conclude that HPV infections of the prostate in general are not as common as has been previously claimed by other investigators.

Tumor differentiation and proliferative activity are important predictors of biological behavior. While routine histological evaluation is fairly adequate to assess differentiation, tumor proliferative activity is difficult to measure. Silver staining for nucleolar organizer regions (AgNORs) is reported to be helpful for assessing tumor proliferation. We investigated the AgNOR counts in 20 formalin fixed, paraffin embedded human prostate tissues in three microscopic fields of 330X, using an image analysis system. A total of 200-700 nuclei were evaluated on histologically controlled areas of nonneoplastic prostate tissue, prostatic intraepithelial neoplasia (PIN), and invasive carcinoma. The values were compared to flow cytometrically obtained synthesis phase fractions (SPF) and immunohistochemically semi-quantitated, proliferative cell nuclear antigen (PCNA) patterns. AgNOR counts were also compared to tumor stage and Gleason's score. The pattern of PCNA staining in formalin fixed specimens was widely variable, probably due to differences in preservation of antigen. The positive counts varied from 0 to 55%, with a mean value of 8.55 +/- 15.9. The SPF values ranged from 5 to 13% with a mean value of 8.50 +/- 2.37. Two of 20 tumors were aneuploid and 18 were of diploid range. The mean AgNOR values in nonneoplastic nuclei (1.836 +/- 0.299), PIN (3.129 +/- 0.295), and invasive tumor cell nuclei (4.737 +/- 0.369) were highly significant (P < 0.0001) when paired differences were compared. AgNOR counts correlated significantly with tumor Gleason's score (P < 0.0145). However, the correlation coefficient for SPF and AgNOR values was not significant (P > 0.24), possibly because of the small number of samples examined. The highest AgNOR counts were found in the two aneuploid tumors. We conclude that AgNOR count may be a potential indicator of cellular proliferation, and possibly a marker of tumor differentiation.

The retinoblastoma tumor suppressor gene (RB gene) has been reported to be deleted and/or modified in a number of human cancers, indicating that dysfunction of this tumor suppressor gene is perhaps critical in the development of many human tumors. In addition to deletion of one copy and/or mutational inactivation of the RB gene, this gene has also been reported to be altered by a small deletion in the promoter sequence in one case of small cell mixed adenocarcinoma of the prostate. A deletion of 105 nucleotides of the RB gene in exon 21, leading to an aberrant short-sized mRNA transcript, has also been reported in one cell line (DU 145) derived from brain metastasis of prostatic adenocarcinoma. We have analyzed tissues from 10 prostate specimens (3 hyperplastic and 7 neoplastic) and one prostate cancer cell line (DU 145) for the presence of short-sized mRNA transcript (exon 21 alterations) by polymerase chain reaction (PCR) using total RNA extracted from frozen tumors and the cell line. None of the prostate tissue showed any evidence of aberrant short-sized mRNA, although it was confirmed in the DU 145 cell line. Simultaneously, we have used DNA-PCR to investigate RB promoter deletion in 23 adenocarcinomas and one small cell carcinoma of the prostate. We also failed to demonstrate any indication of RB promoter deletion at the DNA level in adenocarcinomas. The single case of small cell carcinoma failed to show evidence of any aberration in RB promoter. We therefore conclude that neither RB promoter alterations nor the exon 21 deletion are associated with typical prostate adenocarcinoma.