Human herpesvirus 8 (HHV-8) is the causal agent of all forms of Kaposi's sarcoma, including the iatrogenic form that presents in solid-organ transplant recipients. A longitudinal study of HHV-8 seropositivity was conducted among a cohort consisting of children and adult solid-organ transplant recipients. Antibodies to HHV-8 lytic proteins were detected by an indirect immuno-fluorescence assay in serum samples of 100 transplant recipients. HHV-8 seropositivity increased significantly, from 5.3% before transplantation to 15.8% after transplantation (P < .01). Seropositivity was not related to the age of the patient or the type of organ transplanted. HHV-8 seroconversion occurred in both children and adult recipients. None of the seroconversion events was related to the source of the donor organ. These findings suggest that HHV-8 infection is not uncommon among both adult and children transplant recipients and that viral infection may be acquired from an outside source other than the transplanted organ.

Epinephrine and norepinephrine are produced during psychological stress and can directly bind to cells to induce DNA damage. These effects may have more long-lasting consequences such as DNA mutations resulting in an increased potential for cellular transformation and/or tumor progression. This study examined the molecular effects of a chronic (24 h) in vitro exposure to these stress hormones on murine 3T3 cells. Long exposures (24 h) in dose–response experiments with norepinephrine or epinephrine induced significant increases in DNA damage in treated cells compared to that of untreated controls as measured by the alkaline comet assay. Pre-treatment with a blocking agent (the β-adrenergic receptor antagonist propranolol) eliminated this increase in damage. In addition, both norepinephrine and epinephrine increased cellular transformation, as assessed by growth in soft agar, and 3T3 cells pre-treated with either norepinephrine or epinephrine induced a more rapid onset of tumors and more aggressive tumor growth in nude mice. In summary, incubation of 3T3 cells with catecholamines results in long-term DNA damage as measured by increased transformed phenotypes and tumor progression, indicating that they are important mediators of stress effects on genomic instability and vulnerability to tumor formation.

BackgroundTo 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 MethodsAntibodies 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 ResultsAmong 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) ConclusionsHHV-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