Elevated Serum PSA is Associated With Human Herpesvirus 8 Infection and Increased Circulating Cytokine Levels in Men From Tobago.

BACKGROUND: Serum-prostate specific antigen (PSA) levels have been used for many years as a biomarker for prostate cancer. This usage is under scrutiny due to the fact that elevated PSA levels can be caused by other conditions such as benign prostatic hyperplasia and infections of or injury to the prostate. As a result, the identification of specific pathogens capable of increasing serum levels of PSA is important. A potential candidate responsible for elevated PSA is human herpesvirus 8 (HHV-8). We have reported previously that HHV-8 is capable of infecting and establishing a latent infection in the prostate. In this current study we test the hypothesis that HHV-8 infection is associated with elevated PSA levels. Circulating cytokine levels between men with elevated PSA and controls are also compared. METHODS: HHV-8 serostatus was determined among men with elevated serum PSA (≥4 ng/ml; n = 168, no prostate cancer on biopsy) and age-matched controls (PSA <4 ng/ml; n = 234), Circulating cytokine levels were determined among a subset of each group (116 with elevated PSA and 85 controls). RESULTS: Men with an elevated serum PSA were significantly more likely to be HHV-8 seropositive (42.9%) than the age-matched cancer-free men (22.2%; OR 2.51; 95%CI 1.48-4.29, P = 00001). Comparison of circulating cytokine levels between men with elevated serum PSA and controls indicated that elevated serum PSA is associated with a pro-inflammatory response with a mixed Th1/Th2 response while HHV-8 infection was associated with significantly higher levels of IL12p70, IL-10, and IL-13 indicating a Th2 immune response. CONCLUSIONS: We found a significant association between HHV-8 infection and increased levels of serum PSA. In an age of patient-centered medicine, men with an elevated serum PSA should be considered for HHV-8 serology testing to determine if HHV-8 is responsible for the elevated PSA. Prostate 77: 617-624, 2017. © 2017 Wiley Periodicals, Inc.

Human herpesvirus 8 infection contributes to a T helper 2 immune response in men from Tobago with prostate cancer.

OBJECTIVES: To compare the cytokine profile between human herpesvirus 8 seropositive and seronegative men with and without prostate cancer. METHODS: The study sample was obtained from the Tobago Prostate Survey, an ongoing study of prostate cancer in the Caribbean island of Tobago. Participants in the study were recruited mostly by public service announcement and by word of mouth. For analyses of circulating levels of pro-inflammatory cytokines, participants with biopsy-confirmed prostate cancer (n = 79) were compared with control participants (n = 87). RESULTS: Cytokine analyses showed a T helper 2 response with suppressed T helper 1 response in prostate cancer patients, as evidenced by significantly increased levels of interleukin-13 and reduced levels of interleukin-12p70. Herpesvirus 8 seropositive men showed significantly increased levels of interleukin-13 and interleukin-10. At logistic regression analyses, interleukin-12p70 predicted prostate cancer in 94.4% of human herpesvirus 8 seropositive men. CONCLUSIONS: These findings show that prostate cancer elicits an antitumor, T helper 2 response with a suppressed T helper 1 response. Human herpesvirus 8 infection results in a similar immune response supporting the hypothesis that in Tobago, human herpesvirus 8 establishes a chronic infection that can contribute to an immune response favoring the formation and survival of prostate cancer.

Human herpesvirus 8 establishes a latent infection in prostates of Tobago men resulting in increased macrophage infiltration.

BACKGROUND: The Caribbean island of Tobago, which is 97% African ancestry, has one of the highest rates of prostate cancer in the world. We have previously reported that human herpesvirus 8 (HHV-8) infection is significantly associated with prostate cancer in Tobago. In this study, we extend those results testing the hypothesis that HHV-8 seropositive Tobagonian men have a chronic HHV-8 infection in their prostates that is associated with increased inflammation. METHODS: Prostate sections were screened by immunohistochemistry for the expression of HHV-8 proteins K8.1 and LANA-1 and for presence of B cells (CD20) and macrophages (CD68). RESULTS: HHV-8 antigen expression representing lytic and latent infections was seen in 73.9% of prostates from HHV-8 seropositive subjects. Latent infections were seen predominantly in glandular epithelia whereas lytic gene expression was seen mainly in macrophages in prostate stroma. Macrophage infiltrates were significantly increased in sections expressing HHV-8 proteins. CONCLUSION: HHV-8 establishes a chronic latent infection in the prostate, which is associated with an increased macrophage infiltrate.

Human herpesvirus 8 seroconversion in a population-based cohort of men in Tobago.

Human herpesvirus 8 (HHV-8) is the causal agent of Kaposi's sarcoma (KS). In Tobago, KS is not common; however, HHV-8 seropositivity has been reported to be 39.9% in men with prostate cancer compared to <22.9% in healthier women and men. To understand HHV-8 transmission, we examined HHV-8 seroconversion and seroreversion, and risk factors for these changes in Tobago men. Serum specimens from a sub-cohort of Tobago Prostate Survey men, aged 40-81 years (n = 381/442), were collected at baseline and a subsequent visit between 3 and 9 years and tested for HHV-8 seropositivity using an immunofluorescence assay for antibodies against HHV-8 lytic antigens. Poisson distribution was used to calculate HHV-8 seroconversion and seroreversion rates and their 95% confidence intervals. Differences in baseline characteristics between HHV-seroconverters versus persistent HHV-8 seronegative men and HHV-8 seroreverters versus HHV-8 seropositive men were examined. HHV-8 seropositivity was 12.3% (N = 381) at baseline, with HHV-8 seropositivity significantly higher in increasing age groups, 40-49 (4.0%) to 70-81 (37.5%) years (P-value trend <0.0001). HHV-8 seroconversion and seroreversion rates were 0.23 per 100 person-years (95% C.I., 0.06-0.58) and 2.42 per 100 person-years (95% C.I., 0.89-5.26), respectively. There were significantly more HHV-8 seroconverters who reported "ever smoked cigarettes of >6 months" at baseline compared to HHV-8 persistent seronegative men (P-value = 0.03). Baseline characteristics of HHV-8 seroreverters did not differ from persistent seropositive men. Low HHV-8 seroconversion and seroreversion rates were found. Data suggest that HHV-8 transmission occurred at earlier ages, <40 years, in Tobago men.

Human herpesvirus 8 seroprevalence among Tobago women and the role of sexual lifestyle behavior.

Human herpesvirus 8 (HHV-8) infection is present in 22.9% of Tobago men. However, seroprevalence and modes of transmission of HHV-8 among Tobago women are not known. HHV-8 seropositivity rates in Tobago women were examined and compared rates to Tobago men of similar ages. To assess possible modes of transmission, sexual behavior among Tobago women was examined to determine its association with HHV-8 seropositivity. A cross-sectional study was conducted in 213 Tobago women, ages 18-65 years, who participated in the Tobago Cervical and Oral Cancer Screening Study. HHV-8 seropositivity was determined by a monoclonal immunofluorescence assay. Age-specific rates were compared to those previously observed in men. Logistic regression analyses were performed to determine the association between HHV-8 seropositivity and sexual behavior among the women. HHV-8 seroprevalence among Tobago women was 14.1% (95% CI, 10-19%), with no significant difference with men of similar age (P-value = 0.741). Age

Elevated seroprevalence of human herpesvirus 8 among men with prostate cancer.

Background. To investigate any epidemiological association between human herpesvirus (HHV)-8 and prostate cancer, we determined the prevalence of HHV-8 seropositivity among prostate cancer case and control subjects in the United States and Trinidad and Tobago.Methods. Antibodies against HHV-8 were detected in 2 independent laboratories using either indirect immunofluorescence assay (IFA) or a combination of enzyme-linked immunosorbent assay and IFA.Results. Among 138 Tobago men with prostate cancer, HHV-8 seroprevalence was 39.9%-significantly higher than that among 140 age-matched control subjects (22.9%; P=.003; odds ratio [OR], 2.24; 95% confidence interval [CI], 1.29-3.90). Among 100 US men with prostate cancer, seroprevalence was 20%-significantly higher than that of 177 blood donors (5.1%; P=.001; OR, 4.67; 95% CI, 1.91-11.65) and higher than that of 99 men with cancer not related to HHV-8 (13%; P=.253; 95% CI, 0.77-3.54).Conclusions. HHV-8 seropositivity is elevated among men with prostate cancer compared with control subjects, which suggests that HHV-8 plays a role in the development of prostate cancer.