Cellular senescence as a possible link between prostate diseases of the ageing male

Senescent cells accumulate with age in all tissues. Although senescent cells undergo cell-cycle arrest, these cells remain metabolically active and their secretome - known as the senescence-associated secretory phenotype - is responsible for a systemic pro-inflammatory state, which contributes to an inflammatory microenvironment. Senescent cells can be found in the ageing prostate and the senescence-associated secretory phenotype and can be linked to BPH and prostate cancer. Indeed, a number of signalling pathways provide biological plausibility for the role of senescence in both BPH and prostate cancer, although proving causality is difficult. The theory of senescence as a mechanism for prostate disease has a number of clinical implications and could offer opportunities for targeting in the future.

Cytotoxic T lymphocyte-associated protein 4 antibody aggrandizes antitumor immune response of oncolytic virus M1 via targeting regulatory T cells

Oncolytic virotherapies are perceived as remarkable immunotherapies coming into view and represent highly promising cancer treatments, yet to figure out its specific immune responses and underlying barriers remains critical. Albeit recent studies have demonstrated that oncolytic viruses (OVs) could fine tune tumor microenvironment (TME) to elicit tumor suppression mainly due to effective T-cell responses, the interaction between suppressive T cells and OVs is barely undetermined. Herein, we found that regulatory T cells (Treg cells) were increased in the TME following systemic administration of oncolytic virus M1 along with the higher expression of relative cytokines and chemokines in both mouse RM-1 prostatic carcinoma model and mouse B16F10 melanoma model. Besides, Treg cells expressed high levels of CD25 post-M1 treatment, and its suppressive effect on CD8⁺ T cells was also elevated. Depletion of Treg cells in M1-treated groups significantly reinforced antitumor effect of M1. Specific targeting of Treg cells using cytotoxic T lymphocyte-associated protein 4 (CTLA-4) antibody (Ab) in combination with M1 treatment elicited a more profound tumor suppression and longer overall survival time than M1 alone in both tumor models. Moreover, CTLA-4 Ab further aggrandized antitumor immune response elicited by M1, including increased infiltration of CD45⁺ immune cells and CD8⁺ or CD4⁺ T lymphocytes, decreased ratio of Treg cells to CD4⁺ T lymphocytes, the intensified lymphocytotoxicity and elevated secretion of cytotoxic cytokines like interferon-γ, granzyme B and perforin. Therefore, our findings constituted a suggestive evidence that targeting Treg cells in M1-based oncolytic virotherapy may achieve a highly response in clinical cancer research.

Consequences of interleukin 1β-triggered chronic inflammation in the mouse prostate gland: Altered architecture associated with prolonged CD4+ infiltration mimics human proliferative inflammatory atrophy

BACKGROUND

Elevated expression of the proinflammatory cytokine interleukin 1β (IL-1β) has been observed in expressed prostatic secretions of patients with chronic prostatitis/chronic pelvic pain syndrome, and genetic polymorphisms associated with the IL1B gene are linked to increased risk for aggressive prostate cancer.

METHODS

To study the role of IL-1β expression in prostate inflammation, we examined IL1B expression in human prostatic proliferative inflammatory atrophy (PIA) lesions and developed a tetracycline-regulated human IL1B transgene in the mouse prostate.

RESULTS

Here, we demonstrate that IL1B expression is a common finding in human PIA lesions, which harbored focal IL1B expression in epithelial and stromal compartments. Human IL1B expression in the mouse prostate elicited acute and chronic inflammation. Penetrance and expressivity were variable and tunable by altering transgene dosage and the presence of an exogenous inducible marker antigen (green fluorescent protein). Inflammation was characterized by infiltration of CD4+ T cells, demonstrating an adaptive immune response. Chronic inflammation persisted after doxycycline (Dox) withdrawal. Reactive epithelia increased expression of downstream cytokines, and altered glandular architecture was observed upon sustained induction of IL1B. Immunohistochemical analyses revealed a higher proliferative index and decreased Nkx3.1 expression in inflamed mouse prostates.

CONCLUSIONS

These data implicate IL-1β in human prostate pathology and this model provides a versatile platform to interrogate molecular mechanisms of inflammation-associated prostate pathologies associated with episodic or sustained IL-1β expression.

Serum Autoantibodies in Chronic Prostate Inflammation in Prostate Cancer Patients

Background

Chronic inflammation is frequently observed on histological analysis of malignant and non-malignant prostate specimens. It is a suspected supporting factor for prostate diseases and their progression and a main cause of false positive PSA tests in cancer screening. We hypothesized that inflammation induces autoantibodies, which may be useful biomarkers. We aimed to identify and validate prostate inflammation associated serum autoantibodies in prostate cancer patients and evaluate the expression of corresponding autoantigens.

Methods

Radical prostatectomy specimens of prostate cancer patients (N = 70) were classified into high and low inflammation groups according to the amount of tissue infiltrating lymphocytes. The corresponding pre-surgery blood serum samples were scrutinized for autoantibodies using a low-density protein array. Selected autoantigens were identified in prostate tissue and their expression pattern analyzed by immunohistochemistry and qPCR. The identified autoantibody profile was cross-checked in an independent sample set (N = 63) using the Luminex-bead protein array technology.

Results

Protein array screening identified 165 autoantibodies differentially abundant in the serum of high compared to low inflammation patients. The expression pattern of three corresponding antigens were established in benign and cancer tissue by immunohistochemistry and qPCR: SPAST (Spastin), STX18 (Syntaxin 18) and SPOP (speckle-type POZ protein). Of these, SPAST was significantly increased in prostate tissue with high inflammation. All three autoantigens were differentially expressed in primary and/or castration resistant prostate tumors when analyzed in an inflammation-independent tissue microarray. Cross-validation of the inflammation autoantibody profile on an independent sample set using a Luminex-bead protein array, retrieved 51 of the significantly discriminating autoantibodies. Three autoantibodies were significantly upregulated in both screens, MUT, RAB11B and CSRP2 (p>0.05), two, SPOP and ZNF671, close to statistical significance (p = 0.051 and 0.076).

Conclusions

We provide evidence of an inflammation-specific autoantibody profile and confirm the expression of corresponding autoantigens in prostate tissue. This supports evaluation of autoantibodies as non-invasive markers for prostate inflammation.

[Relations between red cell structure, function and immune homeostasis in prostatic diseases]

Patients with chronic prostatitis alone and in combination with prostatic adenoma have changes in the activity of the complement system, neutrophil function and content of pro- and anti-inflammatory cytokines. Abnormal representation of the proteins of the red cell membrane in patients with prostatic diseases affects structural and functional activity of erythrocytes in these patients. Dynamic changes in immune status of patients with chronic prostatitis and prostatic adenoma correlate with changes in functional red cell activity. This fact helps better understanding of pathogenesis of chronic prostatitis and prostatic adenoma.

Detection of human herpesvirus 8 (HHV-8) in normal prostates

BACKGROUND

Human herpesvirus 8 (HHV-8) DNA has been detected in semen and prostatic tissues in some, but not all reports. We have analyzed prostate tissues from HHV-8 seropositive men for the expression of viral proteins and determined if expression of these proteins are associated with increased inflammation.

METHODS

Paraffin sections of non-cancerous prostates from HHV-8 seropositive (n = 16) and seronegative (n = 2) men who died with AIDS were screened for expression of three viral proteins by immunohistochemistry. Levels of inflammation were determined by expression of CD68 and CD20. Cellular proliferation was determined by expression of Ki67.

RESULTS

Among the 16 HHV-8 seropositive cases, 68.9% (11/16) (95% C.I. = 0.41-0.89) were positive for HHV-8 protein expression, while the 2 seronegative patients showed no HHV-8 protein expression. There was increased inflammation among HHV-8 positive prostates.

CONCLUSIONS

These results demonstrate that HHV-8 is present in normal prostates of HIV-infected men and the expression of viral proteins is associated with increased localized inflammation.

[Prostate specific antigen: its proper diagnostic use]

A TISSUE MARKER: Prostate specific antigen (PSA) is a tissue marker and not a tumor marker. When ordered for the right situation, i.e. when the clinical presentation is compatible with prostatic cancer, PSA assay can be a remarkable tool for early diagnosis and beneficial therapeutic care. IN PATIENTS OVER 70: A PSA assay is not necessarily indicated for men over 70 years of age unless digital exploration of the prostate or other signs suggest prostatic disease. IN PATIENTS UNDER 70: In patients whose life expectancy is greater than 10 to 15 years, serum PSA above the laboratory's upper limit for normal is an indication for ultrasonographic exploration of the prostate with systematic biopsy.

Cryptococcal prostatic abscess in an immunocompromised patient: a case report and review of the literature

A case of cryptococcal prostatic abscess in a 65-year-old Chinese man with immunosuppression from treatment of myasthenia gravis is presented. The patient was diagnosed to have cryptococcaemia when he presented with fever and urinary symptoms. Further investigations confirmed cryptococcal meningitis and imaging studies showed a hypodense lesion in the prostate. This proved to be an abscess and it was deroofed transurethrally. Histology of the prostatic tissue revealed the presence of Cryptococcus. The prostate can be a site of persistent cryptococcal infection and may take the form of an abscess. It should be drained transurethrally to prevent relapse.

Relationship among age, prostate-specific antigen, and prostate volume in men with lower urinary tract symptoms (LUTS) and in different groups of men with and without benign and malignant prostate diseases

BACKGROUND

In order to enhance prostate-specific antigen (PSA) as a predictor of prostate cancer, it is necessary to understand the characteristics of this tumor marker in a population of men without evidence of prostate cancer but who are at risk for developing the condition.

METHODS

In an age-stratified population of 328 men with lower urinary tract symptoms (LUTS), we analyzed the distribution of PSA levels as a function of age and prostate volume, and we analyzed the percentage of age-related variance in PSA that can be explained by the age-related variance in prostate volume.

RESULTS

Classifying the 328 cases with LUTS according to four age groups, a correlation was found between PSA and prostate volume, becoming stronger from the younger (correlation coefficient, -0.1265) to the older group (correlation coefficient, 0.6044). Serum PSA variance per milliliter of prostate volume also increased from the younger (not significant, P > 0.1) to the older age decades (7.3% in men age 70 years or over). Moreover, the results of the regression analysis suggest that 10% of the variance in PSA with age can be accounted for by prostate volume in men under age 50 years, reaching 37% in men age 70 years or more.

CONCLUSIONS

These data confirm that the serum PSA concentration increases with advancing age in the absence of clinically evident prostatic malignancy. In younger patients with LUTS, serum PSA variance with age seems to be less dependent upon the age-related variance in prostate volume.

Elevated serum levels of p105(erbB-2) in patients with advanced-stage prostatic adenocarcinoma

Expression of a truncated or extracellular form (p105erbB-2) of p185erbB-2 has been demonstrated in the sera of breast cancer patients. We examined the levels of p105erbB-2 in the sera of patients with various stages of prostatic adenocarcinoma, in patients with benign prostatic hyperplasia (BPH) and in a series of control male patients hospitalized for illnesses unrelated to the prostate. p105erbB-2 levels did not differ between the controls and BPH patients or between these groups and patients with stage A, B or C adenocarcinomas. In contrast, serum p105erbB-2 levels of patients with stage D adenocarcinomas were significantly elevated when compared with either control or BPH patients. There was no correlation between PSA and p105erbB-2 levels among controls, patients with BPH or patients with prostate cancer. Patients with poorly differentiated tumors (combined Gleason score >7) or moderately differentiated tumors (combined Gleason score 5-7) had higher p105erbB-2 levels as compared to patients with well-differentiated tumors (combined Gleason score <5), though this difference was not statistically significant. There was no correlation between serum p105erbB-2 levels and p185erbB-2 expression in malignant tissue, as determined by immunohistochemistry. However, patients with moderate to strong expression of p185erbB-2 within the adenocarcinomas were approximately 4 times more likely to demonstrate elevated serum p105erbB-2 levels as compared with patients with low expression of p185erbB-2.

Digital rectal examination, serum prostate specific antigen, and prostatic ultrasound: how effective is this diagnostic triad?

Ninety-nine of 105 consecutive men who underwent transrectal prostatic ultrasound (TRUS) at Highland Park Hospital had the results correlated with digital rectal examination (DRE), serum prostate specific antigen (PSA), and biopsy results. Ninety-six cases had evaluable ultrasound studies. Thirty-two of the 99 who underwent biopsy had primary carcinoma of the prostate. Prostate volume, predicted PSA, a ratio of observed/predicted PSA, and Gleason score were examined. There was no correlation between age and prostate volume, volume and the presence of carcinoma, or PSA and Gleason score. Thirty-one point six percent of the abnormal DREs, 36.6% of the abnormal TRUSs, and 40.6% of the elevated PSAs occurred in men with prostatic carcinoma (PCa). If PSA was normal (less than or equal to 4.0 ng/ml) and either DRE or TRUS was abnormal, then the risk of carcinoma was 2.9%. If PSA was elevated, regardless of the other two tests, the risk of finding PCa was at least 38%. If all three tests were abnormal, the risk of carcinoma was 38% in our series and 68% in a meta-analysis. Many men with PSA values between 4 and 10 ng/ml have benign biopsies. However, close future follow-up with consideration of repeat biopsy should be strongly considered.

prostatic xanthoma: a mimic of prostatic adenocarcinoma

Xanthoma is a localized collection of cholesterol-laden histiocytes that is usually idiopathic, but may be seen in patients with hyperlipidemia. We report seven cases of xanthoma involving the prostate, including one arising in a patient with mild hyperlipidemia. Prostatic xanthoma appeared as a solitary microscopic lesion in the peripheral zone (six cases) or transition zone (one case). One needle biopsy specimen with xanthoma was initially interpreted as well-differentiated adenocarcinoma with a clear cell (hypernephroid) pattern, but immunohistochemical studies revealed the histiocytic nature of the proliferation. Five cases (three needle biopsy specimens and two retropubic prostatectomy specimens) contained a solitary xanthoma adjacent to foci of adenocarcinoma. Another xanthoma was present in a transurethral resection specimen with nodular hyperplasia. Although unusual, xanthoma should be considered in the differential diagnosis of clear cell adenocarcinoma and other clear cell proliferations of the prostate, particularly in limited tissue samples, such as from needle biopsies and transurethral resections.

Pre-analytical and biological variability of prostatic acid phosphatase and prostate-specific antigen in serum from patients with prostatic pathology

We determined the pre-analytical and biological variation of prostatic acid phosphatase and prostate-specific antigen in the same patient samples. Prostatic acid phosphatase and prostate-specific antigen were both stable when stored for at least 3 weeks with acidification (acetate buffer) or without acidification, except for prostate-specific antigen in samples stored unacidified at 4 degrees C. A significant elevation of prostate-specific antigen was noted in four patients with benign prostatic hyperplasia between 1/2 and 6 hours after prostatic massage. No significant effect was shown of changes in the glomerular filtration rate on prostate-specific antigen concentration, in spite of its low molecular mass. The estimate of within-subject biological variation showed a coefficient of variation of 33.8% for prostatic acid phosphatase and 14% for prostate-specific antigen. Desirable analytical imprecisions based on these findings were about 17% for prostatic acid phosphatase and 7% for prostate-specific antigen, these goals being achieved in practice for marker values higher than or equal to the upper reference limit.

[The use of prostatilen in treating patients with prostatic diseases]

A clinical trial of polypeptide prostatic preparation prostatilen has been performed in 37 and 15 patients with chronic prostatitis and prostatic adenoma, respectively. The treatment resulted in attenuation of algetic and dysuria symptoms. Copulative function and spermatogenesis improved. The uroflowmetric index rose, while residual urine and leukocyte count in prostatic secretion reduced. The drug demonstrated antibacterial and immunomodulation effects in the absence of adverse reactions. Prostatilen is indicated in: chronic prostatitis, prostatic adenoma stage I, normospermatogenic and toxic sterility, interoceptive copulative dysfunction, dysuria. The drug in recommended for clinical application.

Determination of prostate-specific antigen in serum by immunoradiometric assay

A better understanding is needed of the role of pre-analytical factors if prostate-specific antigen (PSA) is to be reliably used as a tumor marker. Reports on the analytical performance of TANDEM-R PSA (Hybritech, Inc., San Diego, CA) differ considerably with respect to detection limit and imprecision, differences that might be due (e.g.) to the use of different control matrices, to between-batch variations in reagent composition, or to nonrobustness of the assay. During nine months we determined PSA in 986 serum samples from 728 male urology patients and 54 samples from women (25 assay runs). As controls we used two serum pools with low PSA concentration and two widely used commercial controls. The within-assay CV for patients' samples was similar to that found with the commercial controls: 2.6% to 3.4% in the upper part of the normal reference interval. Precision was worse at lower concentrations (CVs 5-10% at about 0.5 micrograms/L). Imprecision tended to be higher at the end of runs. Assay drift for 100-tube runs was -4%. PSA was stable at -20 degrees C during six months. Neither the polyester polymer in SST tubes nor a hemolysate had any detectable effect on PSA values. Clinical analysis of the first 322 patients and all patients with PSA less than or equal to 0.20 micrograms/L highlighted the requirements for strict adherence to sampling instructions and to stringent quality control also at low analyte concentrations (analyte-free sera and sera with PSA concentrations 0.2-0.5 micrograms/L). Values with TANDEM-R PSA and IRMA-Count PSA (Diagnostic Products Corp., Los Angeles, CA) correlated well with no difference in detection limit or with samples from women. Within-assay precision was better with IRMA-Count PSA in the upper part of the normal reference interval and above. The designs of the two assays were compared in a format that is generally applicable for immunoassay kits (NORDKEM kit group, unpublished), and subjective impressions were recorded.

Autoimmune anti-androgen-receptor antibodies in human serum

Circulating autoantibodies to human and rat androgen receptors are present at high titers in the blood sera of some patients with prostate diseases. The antibodies from some serum samples were associated with a purified IgG fraction and interacted with the 3.8S cytosolic androgen-receptor complexes of rat ventral prostate to form 9- to 12S units. Other serum samples, however, formed 14- to 19S units, suggesting that other immunoglobulins might be involved. In the presence of an anti-human immunoglobulin as a second antibody, the androgen-receptor-antibody complexes could be immunoprecipitated. The antibodies interacted with the nuclear and the cytosolic androgen-receptor complexes, either the DNA-binding or the nonbinding form, but not with receptors for estradiol, progestin, or dexamethasone from a variety of sources. Human testosterone/estradiol-binding globulin, rat epididymal androgen-binding protein, or rat prostate alpha-protein (a nonreceptor steroid-binding protein) also did not interact with the antibodies to form immunoprecipitates. About 37% of male and 3% of female serum samples screened had significant antibody titer. The chance of finding serum with a high titer is much better in males older than 66 years than in the younger males or females at all ages. The presence of the high-titer antibodies may make it possible to prepare monoclonal antibodies to androgen receptors without purification of the receptors for immunization.

Immunofluorescent evidence of prior herpes simplex virus type-2 infection in prostate carcinoma

The finding of herpes simplex virus type-2 (HSV-2) particles in prostatic carcinoma (PCa) tissue has led to speculation that the virus might cause this disease. We studied 27 PCa and 33 benign prostatic hyperplasia (BPH) specimens for the presence of HSV-2 antigens by indirect immunofluorescent staining to HSV-2 using commercially prepared rabbit anti-HSV-2 and fluorescein-tagged goat and anti-rabbit antibody. The slides were randomly number coded by an impartial referee then read independently by each investigator. In cases of disagreement, new slides were prepared and read until agreement. The code was then broken. Seven of 27 PCa specimens and 8 of 33 BPH specimens showed positive staining. By contingency table analysis, the results were not statistically different (chi 2 = 0.0224; p greater than 0.8). In our series, there is no difference in the prevalence of HSV-2 staining between PCa and BPH. Further examination of our data failed to show any difference in the prevalence of staining for HSV-2 based on whether the source of the tissue was surgical or autopsy. We conclude that HSV-2 infection of the prostate is common (15/60 = 25%) but probably has no causal relationship to PCa.

Benign lymphocytic angiitis and granulomatosis: a case report with evidence of an autoimmune etiology

Benign lymphocytic angiitis and granulomatosis (BLAG) is characterized by dense benign-appearing infiltrates of mature lymphocytes, plasma cells, and histiocytes within the pulmonary parenchyma and vasculature. The disorder typically is restricted to the lungs and has a good prognosis. The authors report a patient with BLAG and involvement of lung, kidney, and prostate. This is the first report of prominent systemic distribution in this disease. Another unique feature of this case was the presence of serum antinuclear antibodies and evidence of immune complex deposition in both lung and kidney, suggesting an underlying autoimmune disorder. An association of this entity with lymphomatoid granulomatosis (LG) has been suggested, and the prominent genitourinary disease in this patient may be indicative of a transitional stage leading to LG. An autoimmune state may be the underlying stimulus for the development of BLAG and LG.

Prostatic-specific antigen: an immunohistologic marker for prostatic neoplasms

Antiserum to a human prostate-specific antigen was raised in a rabbit and utilized by immunoperoxidase staining to evaluate its potential value as a diagnostic histologic marker for tumors of prostatic origin. All primary and metastatic prostatic malignancies reacted positively, whereas nonprostatic neoplasms did not stain with this procedure. This is the first immunohistochemical marker for prostate gland epithelium which does not represent prostatic acid phosphatase.

Human prostatic acid phosphatases: purification of a minor enzyme and comparisons of the enzymes

The minor enzyme of human prostatic acid phosphatases (pI 5.5) with high specific activity (orthophosphoric monoester phosphohydrolase, acid optimum, EC 3.1.3.2) has been purified for the first time as a pure enzyme protein. The enzyme was a single protein when examined by polyacrylamide gel electrophoresis and isotachophoresis. The specific activity was 1080 micromole per (min X mg) for hydrolysis of 5.5 mmole per liter of p-nitrophenylphosphate at pH 4.8 and 37 C. The purification coefficient was 540 and the recovery of enzyme activity was 2 per cent. The molecular weight of the enzyme subunit when measured by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate was 54,000. The Km of the purified enzyme was 3 X 10(-4) mole per liter for p-nitrophenylphosphate. An antiserum to this enzyme was prepared. The enzyme was cross-reactive with the main enzyme (pI 4.9) of human prostatic acid phosphatases in immunoelectrophoresis. No precipitin arc with the acid phosphatase in the serum of a prostatic carcinoma patient could be shown. Antiserum to the main enzyme caused a precipitin line with the same serum sample.