In-Depth Comparison of Genetic Variants Demonstrates a Close Relationship Between Invasive and Intraductal Components of Prostate Cancer

Intraductal carcinoma (IDC) of the prostate is often associated with concurrent high-grade invasive prostate cancer (PCa) and poor clinical outcomes. In this context, IDC is thought to represent the retrograde spread of invasive prostatic adenocarcinoma into the acini and ducts. Prior studies have demonstrated a concordance of PTEN loss and genomic instability between the IDC and high-grade invasive components of PCa, but larger genomic association studies to solidify our understanding of the relationship between these 2 lesions are lacking. Here, we evaluate the genomic relationship between duct-confined (high-grade prostatic intraepithelial neoplasia and IDC) and invasive components of high-grade PCa using genetic variants generated by whole exome sequencing. High-grade prostatic intraepithelial neoplasia and IDC were laser-microdissected, and PCa and nonneoplastic tissue was manually dissected from 12 radical prostatectomies. A targeted next-generation sequencing panel was used to identify disease-relevant variants. Additionally, the degree of overlap between adjacent lesions was determined by comparing exome-wide variants detected using whole exome sequencing data. Our results demonstrate that IDC and invasive high-grade PCa components show common genetic variants and copy number alterations. Hierarchical clustering of genome-wide variants suggests that in these tumors, IDC is more closely related to the high-grade invasive components of the tumor compared with high-grade prostatic intraepithelial neoplasia. In conclusion, this study reinforces the concept that, in the context of high-grade PCa, IDC likely represents a late event associated with tumor progression.

CDK19 as a diagnostic marker for high-grade prostatic intraepithelial neoplasia

High-grade prostatic intraepithelial neoplasia (HGPIN) is a facultative precursor lesion of prostate cancer (PCa). Multifocal HGPIN in needle biopsies in the absence of PCa indicates a higher risk of cancer detection in subsequent biopsies. Therefore, a reliable diagnosis of HGPIN is of high clinical relevance guiding the management of patients with cancer-negative biopsies. Detection of HGPIN is merely based on morphological features while biomarkers aiding in the diagnosis of HGPIN and its differentiation from benign glands and other glandular lesions are lacking yet. Here, we investigated the expression of CDK19 by immunohistochemistry on prostate needle biopsies of 140 patients who were all diagnosed with PCa using whole tissue sections, and compared CDK19 levels between HGPIN, PCa and adjacent benign glands. In addition, CDK19 was compared to AMACR expression in a subset of intraductal carcinomas (IDC) on radical prostatectomy (RP) specimens. HGPIN was present in 65.7% of biopsies and in 88% associated to adjacent PCa. CDK19 overexpression defined as moderate to high CDK19 expression visible at low magnification was found in 82.6% of HGPIN. In contrast, 89.3% of benign glands were CDK19-negative or demonstrated only low CDK19 expression highlighting a high sensitivity and specificity to accurately detect HGPIN based on CDK19 expression levels. CDK19 was overexpressed in 59% of PCa but did not correlate significantly with the expression of intermingled HGPIN. On RP, CDK19 and AMACR showed no significant difference in the detection rate of IDC. In summary, assessment of CDK19 facilitates accurate and simplified diagnosis of HGPIN with high sensitivity and specificity and aides the differentiation to non-neoplastic glandular alterations. Considering the high clinical significance of diagnosis HGPIN that still has a limited reproducibility among pathologists we suggest CDK19 as diagnostic biomarker for HGPIN.

Glyoxalase 1 Expression as a Novel Diagnostic Marker of High-Grade Prostatic Intraepithelial Neoplasia in Prostate Cancer

Glyoxalase 1 (GLO1) is an enzyme involved in the detoxification of methylglyoxal (MG), a reactive oncometabolite formed in the context of energy metabolism as a result of high glycolytic flux. Prior clinical evidence has documented GLO1 upregulation in various tumor types including prostate cancer (PCa). However, GLO1 expression has not been explored in the context of PCa progression with a focus on high-grade prostatic intraepithelial neoplasia (HGPIN), a frequent precursor to invasive cancer. Here, we have evaluated GLO1 expression by immunohistochemistry in archival tumor samples from 187 PCa patients (stage 2 and 3). Immunohistochemical analysis revealed GLO1 upregulation during tumor progression, observable in HGPIN and PCa versus normal prostatic tissue. GLO1 upregulation was identified as a novel hallmark of HGPIN lesions, displaying the highest staining intensity in all clinical patient specimens. GLO1 expression correlated with intermediate-high risk Gleason grade but not with patient age, biochemical recurrence, or pathological stage. Our data identify upregulated GLO1 expression as a molecular hallmark of HGPIN lesions detectable by immunohistochemical analysis. Since current pathological assessment of HGPIN status solely depends on morphological features, GLO1 may serve as a novel diagnostic marker that identifies this precancerous lesion.

Nuclear overexpression levels of MAGE-A3 predict poor prognosis in patients with prostate cancer

Melanoma antigen gene A3 (MAGE-A3) is one of the most immunogenic cancer testis antigens and is common in various types of cancers. In this study, for the first time, we performed immunohistochemical analysis to evaluate the expression of MAGE-A3 in 153 prostate tissue samples including prostate cancer (PCa), benign prostatic hyperplasia (BPH), and high-grade prostatic intraepithelial neoplasia (HPIN). Increased both nuclear and cytoplasmic expression of MAGE-A3 was significantly found in PCa tissues compared with both HPIN and BPH tissues (nuclear expression at p = 0.011, and cytoplasmic expression at p = 0.034; for both comparisons p < 0.0001, respectively). A significant correlation was observed between higher nuclear and cytoplasmic expressions of MAGE-A3 with Gleason score (p < 0.0001 and 0.006, respectively). Increased expression of MAGE-A3 was associated with shorter biochemical recurrence-free survival (BCR-FS) and disease-free survival (DFS) of patients (p = 0.042 and = 0.0001, respectively). In multivariate analysis, nuclear expression of MAGE-A3 and Gleason score (≤7 vs >7) was independent predictors of the DFS (both; p = 0.019). Nuclear expression of MAGE-A3 was also significantly related to BCR-FS (p = 0.015). MAGE-A3 can be considered as a predictor for poor prognosis and an option for vaccine immunotherapy in patients with PCa.

ERG expression in prostate cancer biopsies with and without high-grade prostatic intraepithelial neoplasia: a study in Jordanian Arab patients

Background: High-grade prostatic intraepithelial neoplasia (HGPIN) is the most likely precancerous lesion for prostatic adenocarcinoma (PCa). Recent molecular studies have shown that HGPIN can harbor TMPRSS2-ERG fusion, a genetic marker also associated with PCa, which may provide an additional risk stratification tool for HGPIN, especially when present as an isolated lesion. Our aim was to assess the frequency of HGPIN and ERG expression in a cohort of prostatic needle core biopsies from Jordanian-Arab patients with PCa.

Materials and methods: We studied 109 needle core biopsies from patients with PCa. Clinical data, including age and preoperative prostate specific antigen (PSA) level, were obtained from patients’ medical records.

Results: HGPIN was present in 31 (28.4 %) of the 109 cases. Of the HGPIN cases, 13 (41.9%) expressed ERG immunostain. ERG expression in HGPIN was independent of patient age at presentation (P=0.4), pre-operative PSA (P=0.9), and the grade, using the novel Grade Groups (P=0.5).

Conclusion: The frequency of HGPIN in our cohort appears similar to the one found in the Western patient populations and demonstrates a comparable frequency of ERG expression in these lesions.

Co-expression of TLR-9 and MMP-13 is associated with the degree of tumour differentiation in prostate cancer

In vitro experiments demonstrated that stimulation of Toll-like receptor 9 (TLR-9) by synthetic TLR-9 ligands induces the invasion of TLR-9-expressing prostate cancer cells through matrix metalloproteinase 13 (MMP-13). However, the clinical value of TLR-9 and MMP-13 co-expression in the pathophysiology of the prostate is unknown. In the study, we evaluated the expression levels and clinical significance of the TLR-9 and MMP-13 in a series of prostate tissues. One hundred and eighty prostate tissues including prostate cancer (PCa) (n = 137), high-grade prostatic intraepithelial neoplasia (HPIN) (n = 18) and benign prostatic hyperplasia (BPH) (n = 25) were immunostained for the TLR-9 and MMP-13 markers. Subsequently, the correlation between the TLR-9 and MMP-13 staining scores and clinicopathological parameters was obtained. Higher expressions of TLR-9 and MMP-13 were found in PCa and high-grade prostatic intraepithelial neoplasia compared to benign prostatic hyperplasia tissues. Among PCa samples, a positive relationship was revealed between the MMP-13 expression and Gleason score (P < 0.001). There was a significant correlation between TLR-9 expression and regional lymph node involvement (P = 0.04). The expression patterns of TLR-9 and MMP-13 markers demonstrated a reciprocal significant correlation between the two markers in the same series of prostate samples (P < 0.001). Furthermore, the Gleason score of TLR-9^high /MMP-13^high and TLR-9^low /MMP-13^low phenotypes showed a significant difference (P = 0.002). Higher expressions of TLR-9 and MMP-13 can confer aggressive behaviour to PCa. Therefore, these markers may be used as a valuable target for tailored therapy of PCa.

Molecular evidence supporting the precursor nature of atypical adenomatous hyperplasia of the prostate

Atypical adenomatous hyperplasia (AAH) of the prostate is characterized by lobular proliferation of closely packed small acini. It is hypothesized that AAH is a precursor lesion for low-grade prostate cancer arising from the transition zone. Telomere dysfunction is common during malignant transformation of epithelia. In this study, we investigate telomere shortening in AAH (n = 93), high-grade prostatic intraepithelial neoplasia (HGPIN) ( n = 68), and prostatic adenocarcinoma (PCA) ( n = 70) using quantitative fluorescence in situ hybridization. Twenty percent (19 of 93) of AAH specimens, 68% (46 of 68) of HGPIN, and 83% (58 of 70) of PCA showed significant telomere shortening. Thirty-two percent of AAH lesions had α-methylacyl-CoA racemase (AMACR) expression, a sensitive and specific marker for HGPIN and PCA. AMACR expression in AAH was seen more frequently in AAH foci with telomere shortening or coexisting PCA. Our findings indicate that a subset of AAH lesions have telomere shortening and AMACR expression, suggesting that these foci may be precursors for PCA.

[The use of ProstaDoz in patients with benign prostatic hyperplasia and coexistent high-grade prostatic intraepithelial neoplasia]

INTRODUCTION

In recent years there has been an increasing interest in the drug treatment of benign prostatic hyperplasia (BPH) to improve the patients quality of life without surgical treatment. In this connection, phytotherapeutic drugs and biologically active dietary supplements (BADS), consisting of a combination of microelements, vitamins and plant extracts, have been increasingly used in addition to synthetic preparations.

OBJECTIVE

To investigate the clinical effectiveness of dietary supplement ProstaDoz in the treatment of BPH with coexistent high-grade prostatic intraepithelial neoplasia (PIN).

MATERIALS AND METHODS

The study group comprised 30 men with BPH and high-grade PIN who were diagnosed with primary biopsy and received ProstaDoz for three months. The control group included 18 patients with the same diagnosis who were treated with Tamsulosin.

RESULTS

After a 3-month intake of the ProstaDoz, a statistically significant reduction was observed in symptom scores for BPH and the quality of life index by 18% (p<0.001) and 16.7% (p<0.001), respectively. The residual urine volume and total serum PSA decreased by 28.3% (p<0.001) and 46.8% (p<0.001), respectively. Unlike the control group, the rate of prostate cancer detection was 6.25 times lower in patients taking ProstaDoz, and 16% of them had lower grade PIN compared with baseline or no PIN at all.

CONCLUSION

The findings suggest that using ProstaDoz in patients with BPH and high-grade PIN contributes to improving the quality of life (QoL) of patients and the regression of dysplasia.

Clinical Significance of Proliferative Inflammatory Atrophy in Negative Prostatic Biopsies

PURPOSE

To analyze the association between prostatic proliferative inflammatory atrophy finding in negative prostate biopsies and future detection of prostate cancer (PCa) and its aggressiveness in men subjected to repeat biopsies, due to persistent suspicion of PCa.

MATERIALS AND METHODS

Prospective and observational study of 474 men scheduled to repeated PBs. Assessment of PIA and its extension in the previous biopsy. PCa detection rate and tumor aggressiveness. Age, serum total PSA, free PSA, percent free PSA (%fPSA), digital rectal exam (DRE), prostate volume (PV), PSA density (PSAD), PSA kinetics (PSAV and PSADT) findings of PIA and HGPIN, and number of affected cores in previous PBs were included in the univariate and multivariate analysis. Aggressive tumors were considered when any Gleason pattern 4 was found.

RESULTS

PCa was detected in 133 men (28.1%). Age, serum total PSA, %fPSA, PV, PSAD, PSAV, PSADT, and PIA finding were significantly associated to PCa detection. However, only age, OR: 1.06 (95%CI: 1.03-1.10), P < 0.01; DRE, OR: 1.76 (95%CI: 1.05-2.92), P = 0.03; %fPSA, OR: 0.96 (95%CI: 0.93-0.99), P = 0.03; PV, OR: 0.98 (95%CI: 0.97-0.99) and PIA finding, OR: 0.49 (95%CI: 0.29-0.83), P < 0.01, were independent predictors of PCa detection. PCa was found in 18% of 159 men with previous PIA finding while in 33% of 315 men without previous PIA (P < 0.01). None of the studied parameters including PIA in the previous biopsy were related with subsequent PCa aggressiveness.

CONCLUSIONS

PIA finding in negative biopsies correlates with a decreased frequency of detecting PCa in men with persistent suspicion of PCa. The aggressiveness of future detected tumors was not associated with previous PIA finding. Prostate 76:1501-1506, 2016. © 2016 Wiley Periodicals, Inc.

Ductal Spread Versus High-Grade Prostatic Intraepithelial Neoplasia: A Diagnostic Pitfall

Ductal spread (DS) of acinar adenocarcinoma of the prostate can lead to an incomplete replacement of the benign epithelium by cancer cells, resulting in a lesion that can be indistinguishable from high-grade prostatic intraepithelial neoplasia (HGPIN). Kovi and colleagues demonstrated 30 years ago that there is a significant association between the presence of DS and local extent of invasive adenocarcinoma, making the distinction between DS and HGPIN clinically relevant. However, despite the existence of certain morphologic features that are suggestive of DS, a definitive differentiation between the aforementioned lesions cannot always be attained.

Intraductal Carcinoma of the Prostate Gland: Recent Advances

Intraductal carcinoma of the prostate (IDC-P) is characterized by prostatic carcinoma involving ducts and/or acini. The presence of IDC-P is usually associated with a high-grade Gleason score, large tumor volume, and adverse prognostic parameters, including extraprostatic extension and seminal vesicle invasion. When present, IDC-P is associated with worse outcomes, regardless of treatment status. IDC-P is included in a broader diagnostic category of atypical cribriform lesions of the prostate gland. This category of lesions also includes high-grade prostatic intraepithelial neoplasia (HGPIN), urothelial carcinoma involving prostatic ducts or acini, and prostatic ductal adenocarcinoma, amongst other intraductal proliferations. Differentiating between these entities is important as they have differing therapeutic and prognostic implications for patients, although differential diagnosis thereof is not always straightforward. The present review discusses IDC-P in regards to its morphological characteristics, molecular features, and clinical outcomes. Given the current state of knowledge, the presence of IDC-P should be evaluated and documented correctly in both radical prostatectomy and needle biopsy specimens, and the clinical implications thereof should be taken into consideration during treatment and follow up.

Clinical significance of proliferative inflammatory atrophy finding in prostatic biopsies

BACKGROUND

Proliferative inflammatory atrophy (PIA) has been involved in prostatic carcinogenesis. However, little is known about the clinical significance of a PIA finding in prostatic biopsies (PBs). The aim of this study is to determine the incidence of prostate inflammatory atrophy (PIA) in prostate biopsies (PBs), its association to high-grade prostatic intraepithelial neoplasia (HGPIN), prostate cancer (PCa), and tumor aggressiveness.

METHODS

Prospective and observational study of PIA lesion in 528 extended PBs and 200 radical prostatectomy specimens (RPS).

OUTCOME MEASUREMENTS

PIA, HGPIN, PCa incidence, Gleason score, clinical and pathologic tumor stage and insignificant tumor rate. Univariate and multivariate analysis.

RESULTS

Overall incidence of PIA and HGPIN was 30.3% and 54%. In RPS, the incidence was 30.5% and 72%, respectively. No significant association was found between PIA and HGPIN. Overall PCa detection rate in PBs was 38.1%. PCa was found in 27.5% PBs with PIA and 42.7% of those without PIA, P < 0.001. In contrast, PCa was detected in 50.9% of PBs with HGPIN and 23% of those without HGPIN, P = 0.001. Multivariate analysis revealed that PIA decreased the risk of PCa, OR:0.59 (95%CI:0.37-0.95), P = 0.029, while HGPIN increased OR:3.16 (95%CI:2.04-4.90), P = 0.001. PIA was not related to Gleason grade and clinical stage, however it was associated to an insignificant tumors increase, OR:3.08 (95%CI:1.09-8.7), P = 0.033. The information in RPS suggests that PIA is associated with less aggressive tumors and a higher probability of insignificant tumors.

CONCLUSIONS

PIA is present in one third of PBs, HGPIN in one half of them, and no association exists between both lesions. Contrary to HGPIN, PIA finding is associated to lower risk of PCa detection. Tumors accompanying PIA seem to be less aggressive and have a greater probability of being insignificant.

Heterogeneous clinicopathological features of intraductal carcinoma of the prostate: a comparison between "precursor-like" and "regular type" lesions

Intraductal carcinoma of the prostate (IDC-P) has been described as a lesion associated with intraductal spread of invasive carcinoma and consequently aggressive disease. However, there are a few reported cases of pure IDC-P without an associated invasive component, strongly suggesting that this subset of IDC-P may represent a precursor lesion. We compared the clinicopathological features between the morphologically "regular type" IDC-P and "precursor-like" IDC-P. IDC-P was defined as follows; 1) solid/dense cribriform lesions or 2) loose cribriform/micropapillary lesions with prominent nuclear pleomorphism and/or non-focal comedonecrosis. We defined precursor-like IDC-P as follows; 1) IDC-P without adjoining invasive adenocarcinoma but carcinoma present distant from the IDC-P or 2) IDC-P having adjoining invasive microcarcinoma (less than 0.05 ml) and showing a morphologic transition from high-grade prostatic intraepithelial neoplasia (HGPIN) to the IDC-P. IDC-P lacking the features of precursor-like IDC-P was categorized as regular type IDC-P. Of 901 radical prostatectomies performed at our hospital, 141 and 14 showed regular type IDC-P and precursor-like IDC-P in whole-mounted specimens, respectively. Regular type IDC-P cases had significantly higher Gleason score, more frequent extraprostatic extension and seminal vesicle invasion, more advanced pathological T stage, and lower 5-year biochemical recurrence-free rate than precursor-like IDC-P cases. Multivariate analysis revealed nodal metastasis and the presence of regular type IDC-P as independent predictors for biochemical recurrence. Our data suggest that IDC-P may be heterogeneous with variable clinicopathological features. We also suggest that not all IDC-P cases represent intraductal spread of pre-existing invasive cancer, and a subset of IDC-P may be a precursor lesion.

V-ets erythroblastosis virus E26 oncogene homolog (avian)/Trefoil factor 3/high-molecular-weight cytokeratin triple immunostain: a novel tissue-based biomarker in prostate cancer with potential clinical application

Trefoil factor 3 (TFF3) is associated with various cancers and overexpressed in a subset of prostate cancers. Functional studies suggest that v-ets erythroblastosis virus E26 oncogene homolog (avian) (ERG) down-regulates TFF3 expression in hormone-naïve prostate cancer. To characterize this inverse relationship, we developed a triple immunostain encompassing ERG, TFF3, and high-molecular-weight cytokeratin. Triple stain was performed on 96 tumors and 52 benign cases represented in tissue microarrays. Distinct ERG and TFF3 protein was expressed in 45% (43/96) and 36% (35/96) of prostate cancers, respectively. Coexpression was observed in 5% (5/96) of tumor cases, and 24% (23/96) did not express ERG or TFF3. The inverse expression of ERG and TFF3 was significant (P < .0001), with 57% (30/53) of ERG-negative tumors demonstrating TFF3 expression. Sensitivity and specificity of combined ERG and TFF3 expression in detecting prostate cancer were 76% and 96%, respectively. The feasibility of triple immunostain protocol was validated in a set of 76 needle biopsies. The application of this multiplex in situ biomarker for molecular characterization of prostate cancer and as a supplemental diagnostic and prognostic tool in prostate needle biopsies should be further explored.

Epithelial cell adhesion molecule (EpCAM) is associated with prostate cancer metastasis and chemo/radioresistance via the PI3K/Akt/mTOR signaling pathway

Prostate cancer (CaP) is the second leading malignancy in men. The role of epithelial cell adhesion molecule (EpCAM), also known as CD326, in CaP progression and therapeutic resistance is still uncertain. Here, we aimed to investigate the roles of EpCAM in CaP metastasis and chemo/radioresistance. Expression of EpCAM in CaP cell lines and human CaP tissues was assessed using immunofluorescence and immunohistochemistry, respectively. EpCAM was knocked down (KD) in PC-3, DU145 and LNCaP-C4-2B cells using small interfering RNA (siRNA), and KD results were confirmed by confocal microscope, Western blotting and quantitative real time polymerase chain reaction (qRT-PCR). Cell growth was evaluated by proliferation and colony formation assays. The invasive potential was assessed using a matrigel chamber assay. Tumorigenesis potential was measured by a sphere formation assay. Chemo-/radiosensitivity were measured using a colony formation assay. Over-expression of EpCAM was found in primary CaP tissues and lymph node metastases including cancer cells and surrounding stromal cells. KD of EpCAM suppressed CaP proliferation and invasive ability, reduced sphere formation, enhanced chemo-/radiosensitivity, and down-regulated E-cadherin, p-Akt, p-mTOR, p-4EBP1 and p-S6K expression in CaP cells. Our findings suggest that EpCAM plays an important role in CaP proliferation, invasion, metastasis and chemo-/radioresistance associated with the activation of the PI3K/Akt/mTOR signaling pathway and is a novel therapeutic target to sensitize CaP cells to chemo-/radiotherapy.

Chinese and Western prostate cancers show alternate pathogenetic pathways in association with ERG status

We have previously reported genetic differences between Western and Chinese prostate cancers, including different frequencies of ERG rearrangements. We investigated further ERG expression and rearrangements in prostate cancers and high-grade prostatic intraepithelial neoplasia (HGPIN) from the UK and China to determine differences between these two populations by tissue microarray based immunohistochemistry and fluorescence in situ hybridization. In keeping with our previous observation, that ERG was rearranged at a higher frequency in UK prostate cancer samples (38%, 58/155) than Chinese ones (8%, 7/93), ERG rearrangements were also found in 21% (4/19) and 0% (0/19) foci of HGPIN in UK and Chinese samples respectively. ERG nuclear expression in UK cancers (34%, 54/160) was significantly higher than that in Chinese ones (10%, 9/88) (p<0.001). ERG nuclear expression in UK HGPIN (28%, 11/39) was higher than that in Chinese HGPIN (0%, 0/9), but without statistical significance (p=0.193). ERG nuclear expression was correlated to ERG rearrangements in both UK (Kappa=0.686) and Chinese (Kappa=0.565) cancers. These data demonstrate that ERG rearrangement and expression frequencies are different in prostate cancers from UK and China as early as the precursor lesion, HGPIN. The nuclear expression is associated with ERG rearrangements which mainly occur in the Western samples. UK and Chinese prostate cancers may be the result of different genetic mechanisms.

Immunohistochemical expression and localization of somatostatin receptor subtypes in androgen ablated prostate cancer

OBJECTIVE

The aim was to examine the expression and localization of the five somatostatin receptors (termed SSTR1-5) in radical prostatectomies (RPs) from patients with prostatic adenocarcinoma (PCa) under complete androgen ablation (CAA) before operation.

MATERIAL

The five SSTRs were evaluated in the epithelial, smooth muscle and endothelial cells of normal-looking epithelium (Nep), high-grade prostatic intraepithelial neoplasia (HGPIN) and PCa in 20 RPs with clinically detected PCa from patients under CAA. 20 RPs with clinically detected PCa from hormonally untreated patients were used as control group.

RESULTS

Concerning the secretory cells (i) membrane staining was seen for SSTR3 and SSTR4; the mean percentages of positive cells, higher in SSTR3 than in SSTR4, decreased sharply in HGPIN and PCa compared with Nep; the mean percentages in the androgen ablated group were 30-90% lower than in the untreated; (ii) cytoplasmic staining was seen for all 5 SSTRs; the mean percentages of positive cells in Nep, HGPIN and PCa of the untreated group were similar, and in general as high as 80% or more; in the treated group, the Nep values were similar to those in the untreated, whereas the values in HGPIN and PCa were lower for SSTR1, 3 and 5, with a decrease of 30% for SSTR1; (iii) nuclear staining was seen with SSTR4 and SSTR5, the mean percentages for the former being much lower than for the latter; treatment affected both HGPIN and PCa, whose proportions of stained cells were 30-55% lower than in the untreated group. Cytoplasmic staining in the basal cells was seen for all 5 SSTRs, both in Nep and HGPIN. The values in the treated group were lower than in the other, the difference between the two group being in general comprised between 10 and 40%. Treatment did not affect SSTR staining in the smooth muscle and endothelial cells.

CONCLUSIONS

The present study expands our knowledge on the expression and localization of the five SSTRs in the prostate following CAA.

The development of lonidamine for benign prostatic hyperplasia and other indications

Lonidamine (LND) is a compound originally developed as an infertility drug. By capitalizing on the unique energy requirements of many solid tumors including benign prostatic hyperplasia (BPH), LND has shown efficacy as an adjunct to either radiation or chemotherapy in the treatment of several advanced solid organ malignancies such as lung, breast, head and neck, and liver metastases. It has an excellent safety profile in over 20 years of use in Italy in thousands of cancer patients. Preliminary data suggest that it is safe and effective in the treatment of lower urinary tract symptoms associated with BPH by metabolically targeting the unique dependency of the prostate on energy production by glycolysis instead of the aerobe Krebs cycle. The observed effects include a fast reduction in serum prostate-specific antigen and prostate volume, and simultaneous improvements in symptoms and urinary flow rate. The fact that prostate cancer and high-grade prostatic intraepithelial neoplasia have similar metabolic circumstances suggests that LND might also be effective in various stages of the prostate cancer carcinogenesis.

Drug therapies for eradicating high-grade prostatic intraepithelial neoplasia in the prevention of prostate cancer

High-grade prostatic intraepithelial neoplasia (HGPIN) is a precursor to invasive prostate cancer observed as an isolated entity in a growing subset of men undergoing prostate biopsy. The presence of HGPIN predicts an increased risk of 1) coexisting occult prostate cancer at baseline and 2) delayed progression to prostate cancer. As such, men with HGPIN represent a population at high risk for the development of prostate cancer. Because the current recommended therapy is observation and delayed-interval biopsies until cancer develops, a well-tolerated therapeutic agent capable of interrupting the progression of HGPIN to cancer is highly desirable. Given the known cancer-stimulatory effects of estrogens in the prostate, the use of selective estrogen receptor modulators (SERMs) to provide an antiestrogen effect represents a novel strategy for prostate cancer prevention. Recent phase II data from trials using toremifene in the treatment of men with HGPIN validate the use of SERMs as a rational and provocative strategy for the prevention of prostate cancer.