Siobhan Sutcliffe

Nuclear MYC Protein Overexpression is an Early Alteration in Human Prostate Carcinogenesis

The MYC onco-protein is a transcription factor that regulates cell proliferation, metabolism, protein synthesis, mitochondrial function and stem cell renewal. A region on chromosome 8q24 encompassing the MYC locus is amplified in prostate cancer, but this occurs mostly in advanced disease suggesting that MYC alterations occur late in prostate cancer. In contrast, MYC mRNA is elevated in most prostate cancers, even those of relatively low stage and grade (eg Gleason score 6) suggesting that MYC plays a role in initiation. However, since MYC protein levels are tightly regulated, elevated MYC mRNA does not necessarily imply elevated MYC protein. Thus, it is critical to determine whether MYC protein is elevated in human prostate cancer, and if so, at what stage of the disease this elevation occurs. Prior studies of MYC protein localization have been hampered by lack of suitable antibodies and controls. We utilized a new anti-MYC antibody coupled with genetically defined control experiments to localize MYC protein within human tissue microarrays consisting of normal, atrophy, PIN, primary adenocarcinoma, and metastatic adenocarcinoma. Nuclear overexpression of MYC protein occurred frequently in luminal cells of PIN, as well as in most primary carcinomas and metastatic disease. MYC protein did not correlate with gain of 8q24, suggesting alternative mechanisms for MYC overexpression. These results provide evidence that upregulation of nuclear MYC protein expression is a highly prevalent and early change in prostate cancer and suggest that increased nuclear MYC may be a critical oncogenic event driving human prostate cancer initiation and progression.

PTEN Protein Loss by Immunostaining: Analytic Validation and Prognostic Indicator for a High Risk Surgical Cohort of Prostate Cancer Patients

Purpose: Analytically validated assays to interrogate biomarker status in clinical samples are crucial for personalized medicine. PTEN is a tumor suppressor commonly inactivated in prostate cancer that has been mechanistically linked to disease aggressiveness. Though deletion of PTEN, as detected by cumbersome FISH spot counting assays, is associated with poor prognosis, few studies have validated immunohistochemistry (IHC) assays to determine whether loss of PTEN protein is associated with unfavorable disease. Experimental Design: PTEN IHC was validated by employing formalin fixed and paraffin-embedded isogenic human cell lines containing or lacking intact PTEN alleles. PTEN IHC was 100% sensitive and 97.8% specific for detecting genomic alterations in 58 additional cell lines. PTEN protein loss was then assessed on 376 prostate tumor samples, and PTEN FISH or high resolution single nucleotide polymorphism microarray analysis was done on a subset of these cases. Results: PTEN protein loss, as assessed as a dichotomous IHC variable, was highly reproducible, correlated strongly with adverse pathologic features (e.g., Gleason score and pathologic stage), detected between 75% and 86% of cases with PTEN genomic loss, and was found at times in the absence of apparent genomic loss. In a cohort of 217 high risk surgically treated patients, PTEN protein loss was associated with decreased time to metastasis. Conclusion: These studies validate a simple method to interrogate PTEN status in clinical specimens and support the utility of this test in future multicenter studies, clinical trials, and ultimately perhaps for routine clinical care. Clin Cancer Res; 17(20); 6563–73. ©2011 AACR.

Plasma Antibodies against Trichomonas vaginalis and Subsequent Risk of Prostate Cancer

Background: Although several previous case-control studies have investigated associations between sexually transmitted infections (STI) and prostate cancer, most have focused on gonorrhea and syphilis, two well-recognized, symptomatic STIs. Another STI of interest for prostate carcinogenesis is trichomonosis, a less well recognized and frequently asymptomatic STI with known prostate involvement. We investigated this infection in relation to incident prostate cancer in a nested case-control study within the Health Professionals Follow-up Study. Methods: Prostate cancer cases were men diagnosed with prostate cancer between the date of blood draw (1993-1995) and 2000 (n = 691). Controls were men who had had at least one prostate-specific antigen test and who were free of prostate cancer and alive at the time of case diagnosis. One control was individually matched to each case by age (n = 691). Serologic evidence of a history of trichomonosis was assessed by a recombinant Trichomonas vaginalis α-actinin IgG ELISA. Results: Thirteen percent of cases and 9% of controls were seropositive for trichomonosis (adjusted odds ratio, 1.43; 95% confidence interval, 1.00-2.03). This association persisted after additional adjustment for such factors as a history of other STIs, and was strongest among men who used aspirin infrequently over the course of their lives (odds ratio, 2.05; 95% confidence interval, 1.05-4.02, Pinteraction = 0.11). Conclusions: Serologic evidence of a history of trichomonosis was positively associated with incident prostate cancer in this large, nested case-control study of male health professionals. As this study is the first, to our knowledge, to investigate associations between T. vaginalis serology and prostate cancer, additional studies are necessary before conclusions can be made. (Cancer Epidemiol Biomarkers Prev 2006;15(5):939–45)

Chronic Inflammation in Benign Prostate Tissue Is Associated with High-Grade Prostate Cancer in the Placebo Arm of the Prostate Cancer Prevention Trial

Background: Chronic inflammation is hypothesized to influence prostate cancer development, although a definitive link has not been established. Methods: Prostate cancer cases (N = 191) detected on a for-cause (clinically indicated) or end-of-study (protocol directed) biopsy, and frequency-matched controls (N = 209), defined as negative for cancer on an end-of-study biopsy, were sampled from the placebo arm of the Prostate Cancer Prevention Trial. Inflammation prevalence and extent in benign areas of biopsy cores were visually assessed using digital images of hematoxylin and eosin–stained sections. Logistic regression was used to estimate associations. Results: Of note, 86.2% of cases and 78.2% of controls had at least one biopsy core (of three assessed) with inflammation in benign areas, most of which was chronic. Men who had at least one biopsy core with inflammation had 1.78 [95% confidence interval (CI), 1.04–3.06] times the odds of prostate cancer compared with men who had zero cores with inflammation. The association was stronger for high-grade disease (Gleason sum 7–10, N = 94; OR, 2.24; 95% CI, 1.06–4.71). These patterns were present when restricting to cases and controls in whom intraprostatic inflammation was the least likely to have influenced biopsy recommendation because their prostate-specific antigen (PSA) was low (<2 ng/mL at biopsy). Conclusion: Inflammation, most of which was chronic, was common in benign prostate tissue, and was positively associated with prostate cancer, especially high grade. The association did not seem to be due to detection bias. Impact: This study supports an etiologic link between inflammation and prostate carcinogenesis, and suggests an avenue for prevention by mitigating intraprostatic inflammation. Cancer Epidemiol Biomarkers Prev; 23(5); 847–56. ©2014 AACR.

Plasma antibodies against Chlamydia trachomatis, human papillomavirus and human herpesvirus type 8 in relation to prostate cancer: a prospective study

Traditionally, case-control studies of sexually transmitted infections and prostate cancer have focused on gonorrhea and syphilis, with overall positive associations. More recently, researchers have begun to expand their focus to include additional sexually transmitted infections, such as Chlamydia trachomatis, human papillomavirus (HPV), and human herpesvirus type 8 (HHV-8) infections. Continuing this investigation, we examined each of these infections in relation to incident prostate cancer in a nested case-control study within the Health Professionals Follow-up Study. Prostate cancer cases were men diagnosed with prostate cancer between the date of blood draw (1993-1995) and 2000 (n = 691). Controls were men free of cancer and alive at the time of case diagnosis who had had at least one prostate-specific antigen test between the date of blood draw and case diagnosis. One control was individually matched to each case by age; year, time of day, and season of blood draw; and prostate-specific antigen screening history before blood draw (n = 691). C. trachomatis and HPV-16, HPV-18, and HPV-33 antibody serostatus were assessed by enzyme-based immunoassays and HHV-8 antibody serostatus was assessed by an immunofluorescence assay. No associations were observed between C. trachomatis [odds ratio (OR), 1.13; 95% confidence interval (95% CI), 0.65-1.96], HPV-16 (OR, 0.83; 95% CI, 0.57-1.23), HPV-18 (OR, 1.04; 95% CI, 0.66-1.64), and HPV-33 (OR, 1.14; 95% CI, 0.76-1.72) antibody seropositivity and prostate cancer. A significant inverse association was observed between HHV-8 antibody seropositivity and prostate cancer (OR, 0.70; 95% CI, 0.52-0.95). As this study is the first, to our knowledge, to observe such an inverse association, similar additional studies are warranted. (Cancer Epidemiol Biomarkers Prev 2007;16(8):1573–80)

The MAPP research network: design, patient characterization and operations

BackgroundThe “Multidisciplinary Approach to the Study of Chronic Pelvic Pain” (MAPP) Research Network was established by the NIDDK to better understand the pathophysiology of urologic chronic pelvic pain syndromes (UCPPS), to inform future clinical trials and improve clinical care. The evolution, organization, and scientific scope of the MAPP Research Network, and the unique approach of the network’s central study and common data elements are described.MethodsThe primary scientific protocol for the Trans-MAPP Epidemiology/Phenotyping (EP) Study comprises a multi-site, longitudinal observational study, including bi-weekly internet-based symptom assessments, following a comprehensive in-clinic deep-phenotyping array of urological symptoms, non-urological symptoms and psychosocial factors to evaluate men and women with UCPPS. Healthy controls, matched on sex and age, as well as “positive” controls meeting the non-urologic associated syndromes (NUAS) criteria for one or more of the target conditions of Fibromyalgia (FM), Chronic Fatigue Syndrome (CFS) or Irritable Bowel Syndrome (IBS), were also evaluated. Additional, complementary studies addressing diverse hypotheses are integrated into the Trans-MAPP EP Study to provide a systemic characterization of study participants, including biomarker discovery studies of infectious agents, quantitative sensory testing, and structural and resting state neuroimaging and functional neurobiology studies. A highly novel effort to develop and assess clinically relevant animal models of UCPPS was also undertaken to allow improved translation between clinical and mechanistic studies. Recruitment into the central study occurred at six Discovery Sites in the United States, resulting in a total of 1,039 enrolled participants, exceeding the original targets. The biospecimen collection rate at baseline visits reached nearly 100%, and 279 participants underwent common neuroimaging through a standardized protocol. An extended follow-up study for 161 of the UCPPS participants is ongoing.DiscussionThe MAPP Research Network represents a novel, comprehensive approach to the study of UCPPS, as well as other concomitant NUAS. Findings are expected to provide significant advances in understanding UCPPS pathophysiology that will ultimately inform future clinical trials and lead to improvements in patient care. Furthermore, the structure and methodologies developed by the MAPP Network provide the foundation upon which future studies of other urologic or non-urologic disorders can be based.Trial registrationClinicalTrials.gov identifier: NCT01098279 “Chronic Pelvic Pain Study of Individuals with Diagnoses or Symptoms of Interstitial Cystitis and/or Chronic Prostatitis (MAPP-EP)”. http://clinicaltrials.gov/show/NCT01098279

Gonorrhea, Syphilis, Clinical Prostatitis, and the Risk of Prostate Cancer

Background: Although previous case-control studies have observed positive associations among gonorrhea, syphilis, clinical prostatitis, and prostate cancer, many may have been susceptible to recall and interviewer biases due to their retrospective designs. Therefore, to investigate these associations without concerns of recall and interviewer biases, we conducted a large, prospective investigation in the Health Professionals Follow-up Study. Methods: In 1992, participants were asked to report their histories of gonorrhea, syphilis, and clinical prostatitis by mailed questionnaire. Prostate cancer diagnoses were ascertained by self-report on the 1994 and each subsequent biennial follow-up questionnaire and confirmed by medical record review. Results: Of the 36,033 participants in this analysis, 2,263 were diagnosed with prostate cancer between the date of return of the 1992 questionnaire and 2002. No association was observed between gonorrhea [adjusted relative risk (RR), 1.04; 95% confidence interval (95% CI), 0.79-1.36] or syphilis (RR, 1.06; 95% CI, 0.44-2.59) and prostate cancer. Overall null results were also observed between clinical prostatitis and prostate cancer (RR, 1.08; 95% CI, 0.96-1.20), although a significant positive association was observed among younger men (<59 years) screened for prostate cancer (RR, 1.49; 95% CI, 1.08-2.06; Pinteraction = 0.006). Conclusions: Gonorrhea and syphilis do not seem to be risk factors for prostate cancer in this cohort of men with a lower burden of sexually transmitted infections. Clinical prostatitis is also unlikely to be a risk factor, although possible roles for prostatitis in younger men and asymptomatic prostatic infection and inflammation cannot be ruled out. (Cancer Epidemiol Biomarkers Prev 2006;5(11):2160–6)

Risk of Urinary Incontinence Following Prostatectomy: The Role of Physical Activity and Obesity

PURPOSE Urinary incontinence is one of the most commonly reported and distressing side effects of radical prostatectomy for prostate carcinoma. Several studies have suggested that symptoms may be worse in obese men but to our knowledge no research has addressed the joint effects of obesity and a sedentary lifestyle. We evaluated the association of obesity and lack of physical activity with urinary incontinence in a sample of men who had undergone radical prostatectomy. MATERIALS AND METHODS Height and weight were abstracted from charts, and obesity was defined as body mass index 30 kg/m(2) or greater. Men completed a questionnaire before surgery that included self-report of vigorous physical activity. Men who reported 1 hour or more per week of vigorous activities were considered physically active. Men reported their incontinence to the surgeon at their urology visits. Information on incontinence was abstracted from charts at 6 and 58 weeks after surgery. RESULTS At 6 weeks after surgery 59% (405) of men were incontinent, defined as any pad use. At 58 weeks after surgery 22% (165) of men were incontinent. At 58 weeks incontinence was more prevalent in men who were obese and physically inactive (59% incontinent). Physical activity may offset some of the negative consequences of being obese because the prevalence of incontinence at 58 weeks was similar in the obese and active (25% incontinent), and nonbese and inactive (24% incontinent) men. The best outcomes were in men who were nonobese and physically active (16% incontinent). Men who were not obese and were active were 26% less likely to be incontinent than men who were obese and inactive (RR 0.74, 95% CI 0.52-1.06). CONCLUSIONS Pre-prostatectomy physical activity and obesity may be important factors in post-prostatectomy continence levels. Interventions aimed at increasing physical activity and decreasing weight in patients with prostate cancer may improve quality of life by offsetting the negative side effects of treatment.

Trichomonosis and subsequent risk of prostate cancer in the Prostate Cancer Prevention Trial

We previously observed a positive association between a history of trichomonosis, a sexually transmitted infection caused by the protozoan, Trichomonas vaginalis, and prostate cancer risk in the Health Professionals Follow‐up Study. To determine the reproducibility of this finding, we conducted a second, prospective investigation of trichomonosis and prostate cancer in the Prostate Cancer Prevention Trial. Participants were men (≥55 years of age) with no evidence of prostate cancer at enrollment (n = 18,882). Men were screened annually for prostate cancer, and if not diagnosed during the trial, were offered an end‐of‐study prostate biopsy. Cases were a sample of men diagnosed with prostate cancer on any biopsy after visit 2 or on their end‐of‐study biopsy (n = 616). Controls were men not diagnosed with prostate cancer during the trial or on their end‐of‐study biopsy (n = 616). Controls were frequency‐matched to cases by age, treatment arm, and family history of prostate cancer. Serum from visit 2 was tested for anti‐T. vaginalis IgG antibodies. No association was observed between T. vaginalis serostatus and prostate cancer. 21.5% of cases and 24.8% of controls had low seropositivity, and 15.2% and 15.0% had high seropositivity. Compared to seronegative men, the odds ratio of prostate cancer for men with low seropositivity was 0.83 [95% confidence interval (CI): 0.63–1.09), and that for men with high seropositivity was 0.97 (95% CI: 0.70–1.34). Given the original strong biologic rationale and potential for prevention, additional studies are warranted to help resolve discrepancies between study findings and to further investigate this hypothesis from a variety of different approaches.

Trichomonosis, a Common Curable STI, and Prostate Carcinogenesis—A Proposed Molecular Mechanism

Trichomonosis, a sexually transmitted infection (STI) caused by the protist Trichomonas vaginalis, has significant public health relevance. The annual incidence is ,8 million women in the United States and 170 million worldwide, with an equal number of infected male partners [1]. Both men and women infected with T. vaginalis are at increased risk for human immunodeficiency virus infection [1]. Recent evidence suggests this STI is associated with increased risk of prostate cancer, the most commonly diagnosed cancer and the second leading cause of cancer death among men in the United States [2]. There is no immunity to T. vaginalis, and a hallmark of this STI agent is persistence. Most T. vaginalis infections in men are asymptomatic, and few are diagnosed and treated; thus, infections persist. In older, pre-antibiotic era studies, T. vaginalis was frequently found in prostate fluid specimens from asymptomatic male partners of women with trichomonosis, leading to the belief that the prostate might serve as the reservoir for trichomonosis in men [3]. Trichomonosis may cause chronic prostatitis, and researchers have identified trichomonads in the prostatic urethra, glandular lumina, submucosa, and stroma [4] and, more recently, in benign hyperplastic prostatic tissue [3]. They also observed foci of nonspecific acute and chronic inflammation, as well as intraepithelial vacuolization, near trichomonads, leading them to propose that trichomonosis might contribute to prostate carcinogenesis [4].