Fermented rape pollen powder can alleviate benign prostatic hyperplasia in rats by reducing hormone content and changing gut microbiota.

Benign prostatic hyperplasia (BPH) can cause urethral compression, bladder stone formation, and renal function damage, which may endanger the life of patients. Therefore, we aimed to develop plant-based preparations for BPH treatment with no side effects. In this study, the Lactiplantibacillus plantarum 322Hp, Lactobacillus acidophilus 322Ha, and Limosilactobacillus reuteri 322Hr were used to ferment rape pollen. The fermented rape pollen was subsequently converted into fermented rape pollen powder (FRPP) through vacuum freeze-drying technology. After fermenting and drying, the bioactive substances and antioxidant capacity of FRPP were significantly higher than those of unfermented rapeseed pollen, and FRPP had a longer storage duration, which can be stored for over one year. To investigate the therapeutic effect of FRPP on BPH, a BPH rat model was established by hypodermic injection of testosterone propionate. The BPH rats were treated differently, with the model group receiving normal saline, the positive control group receiving finasteride, and the low, medium, and high dose FRPP group receiving FRPP at doses of 0.14 g/kg/d, 0.28 g/kg/d, and 0.56 g/kg/d, respectively. The results indicate that medium dose FRPP reduced the levels of hormone such as testosterone, dihydrotestosterone, and oestradiol in rats with BPH by about 32%, thus bringing the prostate tissue of BPH rats closer to normal. More importantly, medium dose FRPP treatment had a significant effect on the composition of gut microbiota in rats with BPH, increasing the levels of beneficial genera (such as Coprococcus and Jeotgalicoccus), and decreasing the levels of harmful pathogens (such as Turicibacter and Clostridiaceae_Clostridium) in the gut. This study showed that medium dose FRPP reduced the hormone level and regulated the unbalanced gut microbiota in BPH rats, thereby alleviating BPH.

The Firmicutes/Bacteroidetes ratio of the human gut microbiota is associated with prostate enlargement.

BACKGROUND: The pathophysiology of the prostate enlargement underlying lower urinary tract symptoms is unknown. Meanwhile, the gut microbiota can contribute to various host conditions. We hypothesized that the gut microbiota plays a role in prostate enlargement. METHODS: We included 128 patients who underwent prostate biopsies at our hospitals between December 2018 and March 2020, excluding those who had used antibiotics within the past 6 months and those who were diagnosed with prostate cancer of cT3 or higher. Patients with prostate volumes ≥30 ml were defined as the prostate-enlargement (PE) group; those with prostate volumes <30 ml were defined as the non-PE group. Their gut microbiotas were analyzed via 16S rRNA metagenomic analyses of rectal swab samples and were compared between the groups. RESULTS: The PE group included 66 patients; the non-PE group included 62 patients. Age, body mass index, and prostate-specific antigen levels did not significantly differ between the groups. Linear discriminant analysis effect size analysis indicated a higher proportion of Firmicutes and Actinobacteria in the PE group and a higher proportion of Bacteroidetes in the non-PE group. The Firmicutes/Bacteroidetes (F/B) ratio was significantly higher in the PE group than in the non-PE group (2.21 ± 0.39 vs. 1.61 ± 0.40, p = 0.015). CONCLUSION: The F/B ratio of the gut microbiota was associated with prostate enlargement. Although the detailed mechanisms are unclear, the gut microbiota might affect prostate enlargement.

The impact of urine microbiota in patients with lower urinary tract symptoms.

INTRODUCTION: Inflammation and infection are causative factors of benign prostatic hyperplasia (BPH). Urine is not sterile, and urine microbiota identified by DNA sequencing can play an important role in the development of BPH and can influence the severity of lower urinary tract symptoms (LUTS). MATERIALS AND METHODS: We collected mid-stream voided urine samples from BPH patients and control participants and stored them in a freezer at - 80 °C. All enrolled participants were requested to provide information about their clinical characteristics and complete the International Prostate Symptom Score (IPSS) questionnaire. Each step of the procedure, including the extraction of the genomic DNA from the urine samples; the amplification by polymerase chain reaction (PCR); PCR product quantification, mixing, and purification; DNA library preparation; and sequencing was performed with quality control (QC) measures. Alpha diversity was indicative of the species complexity within individual urine samples, and beta diversity analysis was used to evaluate the differences among the samples in terms of species complexity. Pearson's correlation analysis was performed to calculate the relationship between the clinical characteristics of the participants and the microbiota species in the urine samples. RESULTS: We enrolled 77 BPH patients and 30 control participants who reported no recent antibiotic usage. Old age, high IPSS and poor quality of life were observed in the participants of the BPH group. No significant differences were observed in the alpha diversity of the samples. In the beta diversity analysis, there was a significant difference between the microbiota in the samples of the BPH and control groups according to ANOSIM statistical analysis. On comparing the groups, the ten bacterial genera present in the samples of the BPH group in descending order of abundance were: Sphingomonas, Bacteroides, Lactobacillus, Streptococcus, Alcaligenes, Prevotella, Ruminococcaceae UCG-014, Escherichia_Shigella, Akkermansia, and Parabacteroides. Spearman's correlation analysis revealed that urine samples showing the presence of the bacterial genera Haemophilus, Staphylococcus, Dolosigranulum, Listeria, Phascolarctobacterium, Enhydrobacter, Bacillus, [Ruminococcus]torques, Faecalibacterium, and Finegoldia correlated with a high IPSS, and severe storage and voiding symptoms (P < 0.05). CONCLUSION: Our current study shows that dysbiosis of urine microbiota may be related to the development of BPH and the severity of LUTS. Further research targeting specific microbes to identify their role in the development of diseases is necessary and might provide novel diagnostic biomarkers and therapeutic options.

Escherichia coli, a common constituent of benign prostate hyperplasia-associated microbiota induces inflammation and DNA damage in prostate epithelial cells.

BACKGROUND: The role of microbiota in the pathophysiology of benign prostate hyperplasia (BPH), especially in creating an inflammatory milieu may not be avoided. The major objectives of this study were to investigate the microbial composition of BPH tissues, its association with inflammation and check the effect of clinically isolated bacteria on prostate epithelial cells. METHODS: The study includes 36 patients with a pathological diagnosis of BPH. Following strict aseptic measures, tissues were collected after transurethral resection of prostate, multiple pieces of the resected tissues were subjected to histopathological analysis, bacterial culture and genomic DNA extraction. Microbial composition was analyzed by culture and/or next-generation sequencing methods. Annotation of operational taxonomy unit has been done with an in-house algorithm. The extent of inflammation was scored through histological evaluation of tissue sections. The effect of clinical isolates on nuclear factor-κB (NF-κB) activity and induction of DNA-damage in the prostate epithelial cells were evaluated. RESULTS: Histopathological analysis of the BPH tissues showed the presence of inflammation in almost all the tissues with a varied level at different regions of the same tissue section and the level of overall inflammation was different from patients to patients. Microbial culture of tissue samples showed the presence of live bacteria in 55.5% (20 out of 36) of the patient tissues. Majority of the isolates were coagulase-positive Staphylococcus, E. coli and Micrococcus spp. Further, V3 16S rRNA sequencing of the DNA isolated from BPH tissues showed the presence of multiple bacteria and the most common phylum in the BPH tissues were found to be Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes. The E. coli, isolated from one of the tissue was able to activate NF-κB and induce DNA damage in prostate epithelial cells. Phospho-histone γH2A.X staining confirmed the presence of cells with damaged DNA lesion in BPH tissues and also correlated with the severity of inflammation. CONCLUSION: Our study has shown that the BPH tissues do have a divergent microbial composition including the commonly found E. coli (phylum Proteobacteria), and these bacteria might contribute to the BPH-associated inflammation and/or tissue damage. The BPH-associated E. coli induced NF-κB signaling and DNA damage in prostate epithelial cells in vitro.

Catheter-associated bacterial flora in patients with benign prostatic hyperplasia: shift in antimicrobial susceptibility pattern.

BACKGROUND: Men with urinary retention secondary to benign prostatic hyperplasia (BPH) are prone to genitourinary infections. Physicians should be aware of the current antimicrobial susceptibility pattern in this population if empirical treatment is needed. The goal of this study was to evaluate variations in prevalence, composition and antimicrobial susceptibility of bacterial flora in men with indwelling catheters subjected to surgery for BPH in chosen time periods since 1994. Necessary changes in empirical therapy were also assessed. METHODS: All patients with indwelling catheters admitted to a single urological center for BPH surgery in the years 1994-1996, 2004-2006, and 2011-2015 were considered. Catheterization times and results of urine cultures from samples collected at admission were evaluated. Susceptibility for selected antimicrobials was compared separately for Gram negative and Gram positive species. For each agent and for their combinations effectiveness of empirical therapy was calculated dividing the number of patients with bacteriuria susceptible to the agents by the total number of patients with bacteriuria. RESULTS: Bacteriuria was present in 70% of 169, 72% of 132, and 69% of 156 men in the respective time periods. The incidence of Gram-positive strains increased from 10 to 37% (P < 0.001). Their susceptibility to amoxicillin/clavulanate was fluctuating (81, 61, 77%; P=NS). No vancomycin-resistant strain was present. Gram-negative flora composition was stable. Their susceptibility decreased to ciprofloxacin (70 to 53%; P = 0.01) and amoxicillin/clavulanate (56 to 37%; P < 0.01) while it increased to gentamycin (64 to 88%; P < 0.001) and co-trimoxazole (14 to 62%; P < 0.001); susceptibility to amikacin remained high (> 85%). Only two cases of resistance to carbapenems in 2004-2006 were found. In vitro effectiveness of amikacin + amoxicillin/clavulanate in empirical therapy was slowly decreasing (87 to 77%; P=NS). Imipenem was found the most effective single agent (90-95%) and its efficacy was even improved by adding vancomycin (97-98%). CONCLUSIONS: Substantial rise in the incidence of Gram-positive species and fluctuations in antimicrobial susceptibility patterns were found. Empirical therapy of genitourinary infection in catheterized men with BPH should now involve antimicrobial agents effective both to Enterococci and Enterobacteriaceae. Periodic monitoring and publishing data on antimicrobial susceptibility for this population is necessary.

The microbiome in prostate inflammation and prostate cancer.

BACKGROUND: The human microbiome may influence prostate cancer initiation and/or progression through both direct and indirect interactions. To date, the majority of studies have focused on direct interactions including the influence of prostate infections on prostate cancer risk and, more recently, on the composition of the urinary microbiome in relation to prostate cancer. Less well understood are indirect interactions of the microbiome with prostate cancer, such as the influence of the gastrointestinal or oral microbiota on pro- or anti-carcinogenic xenobiotic metabolism, and treatment response. METHODS: We review the literature to date on direct and indirect interactions of the microbiome with prostate inflammation and prostate cancer. RESULTS: Emerging studies indicate that the microbiome can influence prostate inflammation in relation to benign prostate conditions such as prostatitis/chronic pelvic pain syndrome and benign prostatic hyperplasia, as well as in prostate cancer. We provide evidence that the human microbiome present at multiple anatomic sites (urinary tract, gastrointestinal tract, oral cavity, etc.) may play an important role in prostate health and disease. CONCLUSIONS: In health, the microbiome encourages homeostasis and helps educate the immune system. In dysbiosis, a systemic inflammatory state may be induced, predisposing remote anatomical sites to disease, including cancer. The microbiome's ability to affect systemic hormone levels may also be important, particularly in a disease such as prostate cancer that is dually affected by estrogen and androgen levels. Due to the complexity of the potential interconnectedness between prostate cancer and the microbiome, it is vital to further explore and understand the relationships that are involved.

The Correlation of Prostate Volume and Prostate-specific Antigen Levels With Positive Bacterial Prostate Tissue Cultures.

OBJECTIVE: To compare prostate volume and prostate-specific antigen (PSA) levels with bacterial growth in prostate tissue cultures. MATERIALS AND METHODS: Fifty male patients who underwent transurethral prostate resection were investigated prospectively. Resection chips from the prostate gland were added to brain-heart infusion medium and incubated. PSA levels were determined preoperatively at our urology ward. The prostate gland volume was estimated by transabdominal ultrasound examination preoperatively. RESULTS: Persons with positive bacterial prostate tissue cultures have a greater prostate volume. This is significant in patients with and without histopathologic signs of prostatitis. Persons with positive bacterial prostate tissue cultures have higher PSA values. This is significant in patients without histopathologic signs of prostatitis. CONCLUSION: People with positive bacterial prostatic tissue culture have a higher prostate volume in comparison with patients with negative culture findings and show a tendency toward increased PSA levels as well.

Simultaneous Detection of Oral Pathogens in Subgingival Plaque and Prostatic Fluid of Men With Periodontal and Prostatic Diseases.

BACKGROUND: Chronic prostatitis (CPr) and benign prostatic hyperplasia (BPH) are complex inflammatory conditions for which etiologic determinants are still poorly defined. Periodontitis is caused by subgingival colonizing bacteria in the oral cavity. The causal effect of periodontal disease on prostatic inflammation has not been established. The purpose of this study is to isolate oral pathogens from expressed prostatic secretions of patients with periodontal disease and CPr or BPH. METHODS: Twenty-four men diagnosed with CPr/BPH participated in the study. A complete periodontal examination consisting of probing depth, bleeding on probing, tooth mobility, gingival index, and plaque index was performed on the men, and prostatic secretion was collected for the study. Dental plaque and prostatic secretion samples were used for analysis of bacterial DNA for Porphyromonas gingivalis (Pg), Prevotella intermedia (Pi), Treponema denticola (Td), and Escherichia coli using reverse transcription-polymerase chain reaction. RESULTS: Six patients were diagnosed with severe, seven with moderate, and four with mild chronic periodontitis. Seventeen of 24 (70.8%) of the prostatic secretion samples showed one or more of the studied oral pathogens. Nine of 10 BPH and eight of 14 patients with CPr had at least one oral pathogen in their prostatic secretions. Pg was found in both prostatic secretion and plaque samples in six of 17 (35.3%) patients, Td was found in both samples in seven of 15 (46.7%) patients, and E. coli was found in both samples in three of 15 (20%) patients. Pi was detected in all dental plaque samples but not in the prostatic secretion. CONCLUSION: An association between chronic inflammatory prostate and periodontal diseases has been demonstrated by the presence of similar bacterial DNA in both prostatic secretion and subgingival dental plaque from the same individual.

The common parasite Toxoplasma gondii induces prostatic inflammation and microglandular hyperplasia in a mouse model.

BACKGROUND: Inflammation is the most prevalent and widespread histological finding in the human prostate, and associates with the development and progression of benign prostatic hyperplasia and prostate cancer. Several factors have been hypothesized to cause inflammation, yet the role each may play in the etiology of prostatic inflammation remains unclear. This study examined the possibility that the common protozoan parasite Toxoplasma gondii induces prostatic inflammation and reactive hyperplasia in a mouse model. METHODS: Male mice were infected systemically with T. gondii parasites and prostatic inflammation was scored based on severity and focality of infiltrating leukocytes and epithelial hyperplasia. We characterized inflammatory cells with flow cytometry and the resulting epithelial proliferation with bromodeoxyuridine (BrdU) incorporation. RESULTS: We found that T. gondii infects the mouse prostate within the first 14 days of infection and can establish parasite cysts that persist for at least 60 days. T. gondii infection induces a substantial and chronic inflammatory reaction in the mouse prostate characterized by monocytic and lymphocytic inflammatory infiltrate. T. gondii-induced inflammation results in reactive hyperplasia, involving basal and luminal epithelial proliferation, and the exhibition of proliferative inflammatory microglandular hyperplasia in inflamed mouse prostates. CONCLUSIONS: This study identifies the common parasite T. gondii as a new trigger of prostatic inflammation, which we used to develop a novel mouse model of prostatic inflammation. This is the first report that T. gondii chronically encysts and induces chronic inflammation within the prostate of any species. Furthermore, T. gondii-induced prostatic inflammation persists and progresses without genetic manipulation in mice, offering a powerful new mouse model for the study of chronic prostatic inflammation and microglandular hyperplasia.

Dying for love: Perimenopausal degeneration of vaginal microbiome drives the chronic inflammation-malignant transformation of benign prostatic hyperplasia to prostatic adenocarcinoma.

Prostatic carcinoma is the second commonest cancer in males and is so common as to become almost holoendemic with advancing age. The recent demonstration that far from being benign, "benign" prostatic hypertrophy is a likely a reaction of the prostate to chronic untreated lower genital tract infection, and that this chronic inflammation is likely the usual precursor to the frequent occurrence of prostatic carcinoma has far reaching implications. The obvious source for the chronic inflammatory stimulus in the prostate is the documented dramatically altered lower female genital microbiota associated with the menopause. Hence the major hypothesis is that prostatic cancer may arise due to chronic infection and inflammation in the prostate gland consequent upon the altered microbiome of the menopausal female genital tract. This has implications for testing and diagnosis, treatment, population health and personal hygiene practices. It suggests that male dyspareunia, although almost never encountered in clinical practice may in fact be relatively common in older males, and in particular if diagnosed, represents a critical opportunity for therapeutic intervention to interrupt the chronic inflammation - cancer transformation and progression which has been well documented in other tissues. It implies that the coordinated application of next generation sequencing to the microbiome of the lower genital tracts of male and female couples, including seminal fluid, will have both research applications to further explore this sequence, as well as finding application as a potential population level screening procedure as is presently done for the "Thin Prep" cervical screening for human papillomavirus in females. Moreover this insight opens up new opportunities for chemointervention and chemoprevention for this important clinicopathological progression. These considerations give rise to the exciting possibility that prostatic malignancy may be preventable by various methods of local hygiene in the female partner or some antibacterial method in males. Since the long term application of oral antibiotics is likely to be of limited efficacy this indicates the need for new antimicrobial solutions.

Antimicrobial activity of Willowherb (Epilobium angustifolium L.) leaves and flowers.

Since the aetiology of benign prostatic hyperplasia (BHP) is still unknown, the use of medicinal herb extracts and products prepared thereof are recommended due to their antimicrobial activity, especially during early stages of BHP. A comparison was performed of the in vitro antimicrobial activity (using broth microdilution assay) of flowers and leaves of willowherb (Epilobium angustifolium L., Onagraceae) from Mt. Velebit (Croatia). The strains (standard ATCC and clinical isolates) of Staphylococcus aureus (including MRSA), Bacillus subtilis, Escherichia coli (including p-fimbriae positive strain), Pseudomonas aeruginosa, Proteus mirabilis, Candida albicans, C. tropicalis, C. dubliniensis and Saccharomyces cerevisiae were susceptible with MIC values between 4.6±0.2 and 18.2±0.8 mg/mL. The results of in vitro studies showed that no differences were found in the antimicrobial activity between the ethanol extracts of leaves and flowers of E. angustifolium. Using the quantitative fluorescent assay with ethidium bromide and acridine orange, the viability of C. albicans ATCC 10231 was assessed after in vitro exposure to E. angustifolium leaf and flower ethanol extracts. Apoptosis of C. albicans blastospores dominated over necrosis in all treated samples after short-term exposure with 6 to 12 mg/mL of extracts. In addition to the valuable biological activity of E. angustifolium extracts, the data obtained from the in vitro diffusion, the dilution assay and antifungal viability fluorescent assay suggest that leaf and flower ethanol extracts of E. angustifolium L. are a promising complementary herbal therapy of conditions such as BHP.

Can mycoplasma contribute to formation of prostate cancer?

PURPOSE: To reveal the possible role of mycoplasmas in the etiopathogenesis of prostate cancer. METHODS: In the study, prostate biopsy was performed on 62 patients with an abnormal digital rectal examination and/or elevated PSA. The patients' age was between 62 and 77 (mean 65.4 years) years. Thirty-one patients had adenocarcinoma of the prostate histopathologically (group 1). From these patients, the specimens were divided into two subgroups as specimens with malignant findings (group 1A) and specimens with benign findings (group 1B). The control group consisted of 31 patients with benign prostatic hyperplasia (group 2). In the specimens, the presence of mycoplasma DNA was investigated by the polymerase chain reaction method. RESULTS: The mycoplasma DNA was found to be positive in 11 (35.4 %) patients in group 1A and in 4 (12.9 %) patients in group 1B. There was no mycoplasma DNA in the patients in group 2. The differences between group 1A and group 1B, and between group 1A and group 2 were statistically significant (p values, respectively, 0.006 and 0.0001). CONCLUSIONS: Our data supported the thesis that mycoplasma infections play a role in the etiopathogenesis of the prostate cancer.

[Use of furamag to prevent inflammatory complications during endoscopic operations in patients with benign prostatic hyperplasia and urolithiasis].

AIM: To improve surgical results in patients with benign prostatic hyperplasia (BPH) and urolithiasis (UL) and to evaluate the efficacy of Furamag used as an agent to prevent infectious and inflammatory complications. SUBJECTS AND METHODS: Seventy-two patients with BPH (n = 36; Group 1) and UL (n = 36; Group 2) were examined. Within each group, the patients were divided into two subgroups: A) those in whom no preventive measures were taken during endoscopic operations; B) those who received Furamag as a preventive agent. The preventive efficacy was evaluated from the urine microbial spectrum and renal microcirculatory values. RESULTS: The preventive use of Furamag could achieve better urine sanitation, normalize renal microcirculatory values, and reduce the incidence of postoperative complications. CONCLUSION: The use of Furamag to prevent intravesical obstruction (IVO) during transurethral prostatic resection and UL reduces the incidence of IVO, results in less noticeable renal microcirculatory disorders, and accordingly assists in lowering the incidence of postoperative complications.

Chronic prostatic infection and inflammation by Propionibacterium acnes in a rat prostate infection model.

Chronic inflammation in the prostate, seen as infiltration of inflammatory cells into the prostate gland in histological samples, affects approximately half the male population without indication of prostate disease, and is almost ubiquitous in patients diagnosed with benign prostate hyperplasia and cancer. Several studies have demonstrated the gram-positive bacterium Propionibacterium acnes to be frequently present in prostate tissue from men suffering from prostate disease. P. acnes has been shown to be associated with histological inflammation in human prostatectomy specimens, and also to induce strong inflammatory response in prostate-derived tissue culture models. The present paper describes a rat model for assessment of the pathogenic potential of P. acnes in prostate. Prostate glands of Sprague Dawley rats (n = 98) were exposed via an abdominal incision and live P. acnes or, in control rats, saline were injected into the ventral and dorso-lateral lobes. Rats were sacrificed 5 days, 3 weeks, 3 months and 6 months post infection, and prostate tissue was analyzed for bacterial content and histological inflammation. Rat sera were assessed for levels of CRP and anti-P. acnes IgG. Live P. acnes could be recovered from the dorso-lateral lobes up to 3 months post infection, while the ventral lobes were cleared from bacteria at that time. In samples up to 3 months post infection, the dorso-lateral lobes exhibited intense focal inflammation. CRP and IgG levels were elevated throughout the span of the experiment, and reached maximum levels 3 weeks and 3 months post infection, respectively. We show that P. acnes have the potential to cause chronic infection in previously healthy prostate, and that the infection has potential to cause chronic histological inflammation in the infected tissue. The high prevalence of P. acnes in human prostate tissue calls for resolution of pathogenic details. The present rat model suggests that complications such as chronic inflammation may be induced by P. acnes infection.

[Treatment of prostatic adenoma].

We used lymphotropic therapy in addition to standard treatment in 116 of 232 patients with benign prostatic hyperplasia. The effect was evaluated in the course of treatment and followed up for a year. Improvement in general condition of the patients, symptoms of infravesical obstruction, size of the prostate, urinary flow rate demonstrated high efficacy of lymphotropic therapy leading to a higher rate of persistent remission and higher quality of life.

[Identification of Mycoplasma in patients with suspected prostate cancer].

AIM: Tests for Mycoplasma hominis, M. genitalium, Ureaplasma urealyticum in males with suspected prostate cancer. MATERIALS AND METHODS: Identification of mycoplasms was performed in prostate tissue samples using universal PCR as well as in serum samples of patients with suspected prostate cancer using ELISA for detection of IgG to M. hominis. Two hundred and fifty samples from each lobe of prostate were obtained from 125 patients with suspected prostate cancer by transrectal polyfocal biopsy. Blood samples were drawn from the same patients for ELISA. RESULTS: Out of 125 patients with suspected prostate cancer, 20.5% were positive for Mycoplasma by PCR. Between studied species, only M. hominis was found in big proportion of analyzed samples. Out of 118 serum samples, 30.5% were positive for IgG to M. hominis in ELISA. CONCLUSION: Fact of presence of Mycoplasma species in tissue of prostate was established in 20.5% pf patients with suspected prostate cancer. Obtained results show that M. hominis is frequently infects prostate tissue and that this infection was more common in patients with high grade prostatic interstitial neoplasia and prostate cancer than in patients with benign changes of prostate tissue or in persons without prostate disease. This allows to suggest that infection with M. hominis could play an important role in development of cancer.

Plasma concentration of Propionibacterium acnes antibodies and prostate cancer risk: results from an Australian population-based case-control study.

BACKGROUND: Recent studies in prostatic tissue suggest that Propionibacterium acnes (P. acnes), a bacterium associated with acne that normally lives on the skin, is the most prevalent bacterium in the prostate and in men with benign prostatic hyperplasia. Its prevalence is higher in samples from patients subsequently diagnosed with prostate cancer. The aim of our study was to test whether circulating levels of P. acnes antibodies are associated with prostate cancer risk and tumour characteristics using plasma samples from a population-based case-control study. METHODS: We measured plasma concentration of P. acnes antibodies for 809 cases and 584 controls using a recently developed ELISA assay. We compared antibody titres between cases and controls using unconditional logistic regression adjusted for batch and variables associated with the study design (i.e., age, year of selection and centre). The primary analysis included P. acnes titres in the model as a dichotomous variable using the median value for controls as the cut-off value. RESULTS: P. acnes antibody titres for both cases and controls ranged from 1 : 16 (i.e., low concentration) to 1 : 65,536 (i.e., high concentration; median value=1 : 1024). The odds ratio for prostate cancer associated with titres at or above the median value was 0.73 (95% CI 0.58-0.91, P=0.005). The association appeared to be particularly strong for advanced prostate cancer (AJCC Stage grouping III-IV) for which the odds ratio was 0.59 (95% CI 0.43-0.81, P=0.001) but there was insufficient evidence that the association differed by tumour stage (p heterogeneity=0.07). CONCLUSION: These results need to be confirmed in prospective studies but they are consistent with the hypothesis that P. acnes has a role in prostate cancer.

The antibody response to Propionibacterium acnes is an independent predictor of serum prostate-specific antigen levels in biopsy-negative men.

OBJECTIVE: To investigate whether the serum titres of Propionibacterium acnes antibodies in patients undergoing prostate biopsy are associated with prostate cancer or markers of prostate disease, including serum prostate-specific antigen (PSA) levels. PATIENTS AND METHODS: The cell wall-associated proteins from P. acnes types IA, IB and II were extracted and characterized by Western blotting and immunoblotting. We developed an enzyme-linked immunosorbent assay (ELISA) based on extracted proteins to determine the anti-P. acnes antibody titres in the sera of 68 patients undergoing prostate biopsy. Correlations between these titres and multiple markers of prostate disease were investigated. RESULTS: In patients with biopsies negative for cancer, a high anti-P. acnes antibody titre was associated with high serum PSA levels (>or=10.0 ng/mL, P = 0.04), and multiple linear regression analysis identified antibody titre as the predominant independent predictor of serum PSA level (P = 0.03). The titre was positively correlated with patient age, prostate volume and aggressive inflammation, suggesting an involvement with benign prostatic hyperplasia (BPH). However in patients with histologically detected cancer, the volume of cancer in the biopsy cores was the predominant independent predictor of serum PSA (P = 0.01). CONCLUSIONS: These results support our hypothesis that P. acnes might be involved in the development of inflammation-related prostate diseases, in particular with BPH. Our ELISA might be valuable for identifying P. acnes infection of the prostate gland in patients with elevated serum PSA levels but a negative biopsy, and might identify men at risk of developing clinical BPH. However, an investigation with more patients is needed to confirm these preliminary findings.

Direct visualization of Propionibacterium acnes in prostate tissue by multicolor fluorescent in situ hybridization assay.

Prostate tissues from patients with prostate cancer and benign prostatic hyperplasia (BPH) frequently contain histological inflammation, and a proportion of these patients show evidence of Propionibacterium acnes infection in the prostate gland. We developed a multicolor fluorescent in situ hybridization (FISH) assay targeting P. acnes 23S rRNA along with a 14-kb region of the P. acnes genome. This assay was used to analyze prostate tissues from patients with prostate cancer and BPH. P. acnes infection of the prostate gland was demonstrated in prostatic tissue in 5 of 10 randomly selected prostate cancer patients. FISH analysis and confocal laser microscopy imaging revealed intracellular localization and stromal biofilm-like aggregates as common forms of P. acnes infection in prostate tissues from both prostate cancer and BPH patients. A sequential analysis of prostate tissue from individual patients suggested that P. acnes can persist for up to 6 years in the prostate gland. These results indicate that P. acnes can establish a persistent infection in the prostate gland. Further study is needed to clarify the link between this bacterium and prostatic inflammation which may contribute to the development of BPH and prostate cancer.