Risk of classical Kaposi sarcoma by plasma levels of Epstein-Barr virus antibodies, sCD26, sCD23 and sCD30

<p>Abstract</p> <p>Background</p> <p>To clarify the immunological alterations leading to classical Kaposi sarcoma (cKS) among people infected with KS-associated herpesvirus (KSHV).</p> <p>Methods</p> <p>In a population-based study of 119 cKS cases, 105 KSHV-seropositive controls, and 155 KSHV-seronegative controls, we quantified plasma soluble cluster of differentiation (sCD) levels and antibodies against Epstein-Barr virus nuclear antigen-1 (anti-EBNA-1) and viral capsid antigen (anti-VCA). Differences between groups in prevalence of low-tertile anti-EBNA-1 and high-tertile anti-VCA were compared by logistic regression. Continuous levels between groups and by presence of cKS co-factors among controls were compared by linear regression and Mann-Whitney-Wilcoxon methods.</p> <p>Results</p> <p>Comparisons of cKS cases to seropositive controls and of seropositive to seronegative controls revealed no significant differences. However, controls with known cKS cofactors (male sex, nonsmoking, diabetes and cortisone use) had significantly lower levels of anti-EBNA (<it>P </it>= 0.0001 - 0.07) and anti-VCA (<it>P </it>= 0.0001 - 0.03). Levels of sCD26 were significantly lower for male and non-smoking controls (<it>P</it>_adj≤ 0.03), and they were marginally lower with older age and cortisone use (<it>P</it>_adj≤ 0.09).</p> <p>Conclusions</p> <p>Anti-EBV and sCD26 levels were associated with cofactors for cKS, but they did not differ between cKS cases and matched controls. Novel approaches and broader panels of assays are needed to investigate immunological contributions to cKS.</p

Risk of classic Kaposi sarcoma with exposures to plants and soils in Sicily

<p>Abstract</p> <p>Background</p> <p>Ecologic and in vitro studies suggest that exposures to plants or soil may influence risk of Kaposi sarcoma (KS).</p> <p>Methods</p> <p>In a population-based study of Sicily, we analyzed data on contact with 20 plants and residential exposure to 17 soils reported by 122 classic KS cases and 840 sex- and age-matched controls. With 88 KS-associated herpesvirus (KSHV) seropositive controls as the referent group, novel correlates of KS risk were sought, along with factors distinguishing seronegatives, in multinomial logistic regression models that included matching variables and known KS cofactors - smoking, cortisone use, and diabetes history. All plants were summed for cumulative exposure. Factor and cluster analyses were used to obtain scores and groups, respectively. Individual plants and soils in three levels of exposure with <it>P</it>_trend≤ 0.15 were retained in a backward elimination regression model.</p> <p>Results</p> <p>Adjusted for known cofactors, KS was not related to cumulative exposures to 20 plants [per quartile adjusted odds ratio (OR_adj) 0.96, 95% confidence interval (CI) 0.73 - 1.25, <it>P</it>_trend= 0.87], nor was it related to any factor scores or cluster of plants (<it>P </it>= 0.11 to 0.81). In the elimination regression model, KS risk was associated with five plants (<it>P</it>_trend= 0.02 to 0.10) and with residential exposure to six soils (<it>P</it>_trend= 0.01 to 0.13), including three soils (eutric regosol, chromic/pellic vertisol) used to cultivate durum wheat. None of the KS-associated plants and only one soil was also associated with KSHV serostatus. Diabetes was associated with KSHV seronegativity (OR_adj4.69, 95% CI 1.97 - 11.17), but the plant and soil associations had little effect on previous findings that KS risk was elevated for diabetics (OR_adj7.47, 95% CI 3.04 - 18.35) and lower for current and former smokers (OR_adj0.26 and 0.47, respectively, <it>P</it>_trend= 0.05).</p> <p>Conclusions</p> <p>KS risk was associated with exposure to a few plants and soils, but these may merely be due to chance. Study of the effects of durum wheat, which was previously associated with cKS, may be warranted.</p

Environmental and immunologic cofactors for the risk of classic Kaposi sarcoma in Sicily

Background. Cofactors for classic Kaposi sarcoma (KS) are unclear and environmental and immunologic factors have been postulated. Using a case-control study in Sicily we examined the relationships between volcanic soil exposure, T-helper (Th) immune shift and classic KS in Sicily. Methods. Histologically confirmed KS cases were identified through surveillance of Sicily's pathology laboratories. Population controls were selected using two-stage cluster sample design and KSHV seropositivity was determined for all subjects using 4 antibody assays. Classic KS cases (n=141) were compared to KSHV seropositive controls (n=123) on residential exposure to four types of soil, categorized with maps from the European Soil Database and direct surveying. A subset of plasma samples was tested for Epstein-Barr nuclear antigen (EBNA) and viral capsid antigen (VCA) antibodies, and for soluble cluster of differentiation sCD23, sCD26, and sCD30, as surrogate markers of Th1/Th2 immunity. Levels and categories of markers were compared between classic KS cases (n=119) and seropositive controls (n=105) to estimate odds of KS, and between the latter and seronegative controls (n=155) to estimate odds of KSHV seropositivity. Results. Residents in communities rich in luvisols (iron rich soil) were approximately 2.7-times more likely to have classic KS than those in communities without luvisols. Among those in luvisol rich communities, the risk was elevated with frequent bathing or tap water drinking. Having KS was unrelated to living in communities high in andosols, tephra, or clay soils. EBV antibody and sCD levels did not differ between cases and seropositive controls, or between seropositive and seronegative controls. Low EBNA/high VCA antibody profile was not associated with KS or KSHV seropositivity. Among controls, subjects with the highest level of VCA antibodies were about twice as likely to be KSHV seropositive. EBV antibodies were lower among those with known KS risk factors, i.e.,male sex, nonsmoking, diabetes and cortisone use. Conclusion. Classic KS in Sicily is associated with living in area with luvisol rich soil, and water as a possible conduit should be investigated. Better methods are needed to assess possible associations of classic KS with Th1/Th2 immunity