Antibodies against human herpesvirus 8 in black South African patients with cancer

Increasing incidence of Kaposi's sarcoma in black South Africans in KwaZulu-Natal, South Africa (1983-2006)

The aim of the study was to describe the temporal trends in the incidence of Kaposi's sarcoma (KS) in black South Africans in KwaZulu-Natal (KZN). The study was designed as a retrospective record review. The incidence of Kaposi's sarcoma was estimated using administrative records for patients receiving care for KS through public sector oncology clinics in KZN, 1983-2006. Annual age-standardized incidence rates were calculated using provincial census data for the denominator. Age-specific rates were calculated for the pre-AIDS (1983-1989) and for the generalized AIDS epidemic eras (2006). Age-standardized incidence of KS increased in KZN from <1:100,000 in 1990 to at least 15:100,000 in 2006; this increase was observed in both men and women. There was a shift in the peak age-specific incidence rates from the sixth decade of life in the pre-AIDS era to the fourth and fifth decades in the AIDS era. In conclusion, KS is a growing public health problem in KZN, South Africa. These data reinforce the need for comprehensive national access to and roll-out of antiretroviral drugs, given their success in prevention and treatment of KS in first-world settings.

Cancer and viral infections in immunocompromised individuals

Over the last 30 years, the increasing use of organ and stem cell transplantation and the AIDS epidemic have led to the realization that some, but not all, human cancers occur more frequently in immunosuppressed individuals. With the notable exception of non-melanoma skin cancer (NMSC), most tumors that show strongly increased incidence rates in both transplant recipients and AIDS patients have been found to have a viral etiology. Among these are Kaposi sarcoma, diffuse large cell B-cell lymphoma, cervical cancer, liver cancer, Merkel cell carcinoma and a subset of Hodgkin's disease. A viral etiology for NMSC, i.e., beta- and gamma-subtypes of human papillomavirus, has been suggested and investigated for many years, but remains controversial. In addition, the moderately increased incidence rates of several other cancers in immunosuppressed individuals (e.g., Vajdic and van Leeuwen, Int J Cancer, in press) could indicate that additional infectious causes for at least some human cancers remain to be discovered. The controversy surrounding the role of cutaneous papillomavirus subtypes in the pathogenesis of NMSC illustrates the difficulties encountered when weighing the epidemiological and molecular biology evidence arguing for an involvement of highly prevalent viruses in certain types of cancer.

Seroprevalence of Kaposi's sarcoma-associated herpesvirus and risk factors in Xinjiang, China

Xinjiang, China is an endemic area for Kaposi's sarcoma (KS) but the seroprevalence of Kaposi's sarcoma-associated herpesvirus (KSHV) and risk factors remain undefined. In this study, antibodies to one KSHV latent protein (ORF73) and two KSHV lytic proteins (ORF65 and ORF-K8.1) were examined in 2,228 subjects from the general population and 37 subjects infected with HIV-1 in Xinjiang, and 560 subjects from the general population in Hubei, a low KS incidence region. The serostatus of a serum sample was defined based on positive results in any one of the three serologic assays. The seroprevalence of KSHV in the general population was higher in Xinjiang than in Hubei (19.2% vs. 9.5%; odds ratios [OR], 2.28; 95% confidence interval [CI], 1.68-3.08; P < 0.001). Among the ethnic groups in Xinjiang, 68 (15.8%) Han, 182 (20.7%) Uygur, 140 (19.9%) Hazakh, 9 (33.3%) Xibo, and 29 (16.8%) Hui were KSHV-seropositive, respectively. Compared to the Han, the latter groups had an increase in the risk of KSHV of 62.2%, 63.8%, 180.1%, and 30.2% (P = 0.003, 0.004, 0.018, and 0.286, respectively). Subjects aged <20, 20-50, and >50 had a seroprevalence of KSHV of 11.8%, 17.9%, and 24.6%, respectively. Compared to subjects aged <20, the latter groups had an increase in the risk of KSHV of 63.3% and 144.5% (P = 0.009 and <0.001, respectively). Subjects infected with HIV-1 in Xinjiang had a seroprevalence of KSHV of 43.2%, and a 220% increase in the risk of KSHV compared to the general population (P < 0.001). Similar results were obtained when the seroprevalence of KSHV was analyzed with any single or two of the three serologic assays alone. Genotyping identified three unique sequences clustered in the A clade. This study indicates that Xinjiang has a high seroprevalence of KSHV. Geographic location, ethnicity, age and HIV-1 infection are risk factors. Serologic and genotyping results suggest the introduction of KSHV into Xinjiang by specific ethnic groups.

Presentation and survival of patients with AIDS-related Kaposi's sarcoma in Jos, Nigeria

AIDS-related Kaposi's sarcoma (AIDS-KS) remains a significant cause of morbidity and mortality. We describe the pattern of presentation and survival in Jos, Nigeria. We identified 48 HIV-positive patients with AIDS-KS and matched them for age and sex with an equal number of HIV-positive patients without AIDS-KS. We compared their clinical, immunological, virological characteristics and survival. They were similar in age and body mass index profile but patients with AIDS-KS had more tuberculosis co-infection (P, 0.02), lower median CD4 count (P, 0.003) and higher mortality (P, 0.002). Surprisingly, patients with AIDS-KS had lower levels of median viral load (29,347 copies/mL) compared with controls (80,533 copies/mL). We recommend specific AIDS-KS therapy in addition to highly active antiretroviral therapy in order to improve survival.

Lack of evidence for frequent heterosexual transmission of human herpesvirus 8 in Zimbabwe

BACKGROUND

There is conflicting evidence about the contribution of heterosexual transmission to the spread of human herpesvirus 8 (HHV-8) in southern Africa. This study evaluated the hypothesis that HHV-8 infection is associated with risk factors for human immunodeficiency virus type 1 (HIV-1) and other sexually transmitted infections among Zimbabwean men.

METHODS

HHV-8 seroprevalence was determined for 2750 participants in the Zimbabwe AIDS Prevention Project cohort of male factory workers in Harare, Zimbabwe. Potential associations of HHV-8 antibody detection with risk factors for HIV-1 infection were examined by univariate analysis. Variables with P < .1 in the univariate analysis were included in a multivariate logistic regression model. HHV-8 seroprevalence was also determined among 297 heterosexual couples.

RESULTS

Prevalence of HHV-8, HIV-1, and HHV-8 and HIV-1 coinfection was 28.5% (95% confidence interval [CI], 26.8%-30.2%), 19.5% (95% CI, 18.0%-20.9%), and 6.5% (95% CI, 5.6%-7.5%), respectively. Detection of HHV-8 antibodies was independently associated with older age and HIV-1 infection but not with number of recent sex partners, marital status, education, condom use, prior sexually transmitted infections, payment for sex, chronic hepatitis B infection, or incident HIV-1 infection. HHV-8 seroprevalence was 31.7% (95% CI, 26.3-37.0) among wives in the couples tested, but HHV-8 infection of wives was not associated with HHV-8 infection of husbands (odds ratio, 1.08; 95% CI, 0.62-1.88; P = .8).

CONCLUSIONS

HHV-8 and HIV-1 infection did not have common sexual risk factors among urban Zimbabwean men. Sexual transmission does not explain the high prevalence of HHV-8 in this population.

Effects of tobacco smoking on cancer and cardiovascular disease in urban black South Africans

Demographic and lifestyle information from 9690 black patients diagnosed with cancer or cardiovascular disease was collected in an ongoing case–control study in Johannesburg, South Africa. Compared to never smokers, the odds ratio (OR) for lung cancer among current smokers was 16.3 (95% confidence interval (CI), 9.6–27.6) for men and 6.4 (95% CI, 4.0–10.4) for women. The corresponding OR for other smoking-related cancers was 4.6 (95% CI, 3.7–5.7) among men and 1.9 (95% CI, 1.6–2.2) among women, and for cardiovascular disease, 3.4 (95% CI, 2.1–5.4) among men and 1.5 (95% CI, 1.1–2.1) among women. Risks were higher among smokers than former smokers, and all risk estimates increased with increasing levels of smoking duration and intensity. Non-electric domestic fuel was associated with approximately 60% increase in the risk of smoking-related cancer, but not cardiovascular disease. Risks for cancers of cervix, oesophagus, oral cavity/pharynx, stomach, larynx, pancreas and anogenital region, as well as squamous cell carcinoma of skin were all significantly higher among current than never-smokers, with ORs ranging from 1.5 for cervix (95% CI, 1.2–1.8) to 14.7 for larynx (95% CI, 7.2–30). The risks of tobacco-related disease reported here are similar to that currently observed in Western countries, even though cigarette consumption is relatively low in this population.

No evidence of sexual transmission of Kaposi's sarcoma herpes virus in a heterosexual South African population

BACKGROUND

The transmission of Kaposi's sarcoma herpes virus (KSHV) in men who have sex with men is clearly associated with sexual risk factors, but evidence of heterosexual transmission of KSHV is conflicting.

METHODS

Sera were obtained from 2103 South African individuals (862 miners, 95 sex workers, 731 female and 415 male township residents; mean age 33.2 years; +/- 10.1). All sera were tested for antibodies to KSHV lytic K8.1 and latent Orf73, HIV, gonococcus, herpes simplex virus type 2 (HSV-2), syphilis and chlamydia. Information on social, demographic and high-risk sexual behavior was linked to laboratory data, to evaluate risk factors, expressed as odds ratios (95% confidence interval) for KSHV.

RESULTS

Overall KSHV and HIV prevalences were 47.5 and 40%, respectively (P = 0.43). The risk of HIV infection was highest in sex workers then female residents and miners, compared with male residents (P < 0.001). HSV-2 infection was highly prevalent (66%) and lower, but still substantial, prevalences (6-8%) were observed for other sexually transmitted infections (STI). No significant difference in KSHV infection was observed among the residential groups (P > 0.05). KSHV was not associated with any of the STI or any measures of sexual behavior (P > 0.05).

CONCLUSION

The pattern of HIV and STI in sex workers suggests high rates of high-risk sexual behavior in this population. The lack of association with high-risk sexual behavior, particularly in sex workers, and with any markers of STI strongly suggest that the sexual mode does not play a significant role in KSHV transmission in this South African population.

High diversity of HHV-8 molecular subtypes in the Amazon region of Brazil: evidence of an ancient human infection

The present study describes the molecular epidemiology of Human herpesvirus 8 (HHV-8) among four Indian tribes (Kararao, Arara Laranjal, Tiriyo, and Zo'e) of the Amazon region of Brazil and a group of HIV-1-infected subjects from the urban population of Belem, Para. Infection was characterized by the presence of antibodies using ELISA (measuring antibodies to ORF59, ORF65, K8.1A, K8.1B, and ORF73), and molecular assays (gene amplification of the regions ORF26 and the variable region VR1). Antibodies to HHV-8 were detected in 66 samples of the 221 Brazilian Amerindians, namely, 6 (25%) in the Kararao, 18 (19.6%) in the Arara Laranjal, 24 (42.9%) in the Tiriyo, and 18 (36.7%) in the Zo'e. Among the 477 HIV-1-infected subjects, antibodies to HHV-8 were present in 74 (15.5%) persons. The ORF26 region was amplified in seven samples, one of the Arara Laranjal, one of the Tiriyo, two of the Zo'e, and three of the HIV-1-infected group. Subtyping of HHV-8 described a high multiplicity of molecular subtypes, including C (Zo'e), E (Tiriyo), and B (HIV-1 infected). Serological results confirm the high prevalence of HHV-8 among Amerindians and the presence of three subtypes in the Amazon region of Brazil, including a unique subtype, which favors the idea of HHV-8 as an ancient human infection within this particular geographical region.

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.

Inflammation in the etiology of prostate cancer: an epidemiologic perspective

The epidemiologic literature on sexually transmitted infections, clinical prostatitis, prostatic calculi, polymorphisms in immune response genes, and nonsteroidal antiinflammatory drug use as potential sources and modifiers of intraprostatic inflammation is reviewed in relation to prostate cancer. Particular emphasis is placed on study methodology and its influence on study findings. Although evidence from reviewed epidemiologic studies, together with laboratory and clinical studies, is suggestive of a role for prostatic inflammation in the etiology of prostate cancer, additional large, prospective studies are necessary to address methodological limitations of existing studies, and to investigate a broader range of potential sources of intraprostatic inflammation.

Human herpesvirus 8 (HHV-8) infection in healthy urban employees from Greece: seroprevalence and associated factors

A cross-sectional study was carried out in healthy company employees from Greece with the aim of assessing the prevalence of human herpesvirus 8 (HHV-8) and identifying risk factors for this herpesviral infection. Serum samples obtained from 955 subjects were tested for antibodies to HHV-8 by the K8.1 enzyme-linked immunosorbent assay (ELISA). Associations between HHV-8 serostatus and potential risk factors were examined using t-test, chi square test, and multivariate logistic regression analysis. HHV-8 prevalence was 7.6% (95% confidence interval (CI): 6.0%, 9.5%) and it increased with age from 6.5% among <30 years old to 13.8% among > or =50 years old subjects (P = 0.006). HHV-8 seropositivity was independently associated with endoscopic examination (odds ratio (OR): 2.01; 95% CI: 1.09, 3.70; P = 0.026), HBsAg positivity (OR: 5.16; 95% CI: 2.02, 13.20; P = 0.001) and age (OR > or =50 years old vs. <50 years old: 2.09; 95% CI: 1.23, 3.52; P = 0.006). No statistically significant associations between HHV-8 positive status and gender, occupational status, surgery, transfusion, tattoos/body piercing, multiple sex partners, weakness/fatigue, HCV status were observed. HHV-8 is prevalent in Greece. The strong association between HBV infection and HHV-8 positive status supports the hypothesis of an association between these two viral infections. The association between HHV-8 seropositivity and endoscopic examination requires further investigation.

Traditional practices and exposure to bodily fluids in Lusaka, Zambia

OBJECTIVES

To ascertain if there are specific sociocultural and behavioural practices associated with the exposure to saliva, semen and vaginal fluids, particularly through child-rearing practices and the use of traditional medicine in Lusaka, Zambia.

METHODS

We conducted 11 focus group discussions with men and women from diverse ethnic and socioeconomic backgrounds (n = 105) in Lusaka, Zambia in March 2004. We also conducted a brief sociodemographic survey of all focus group participants.

RESULTS

Discussions indicated that saliva was used while engaging in home health care practices associated with childcare and the use of traditional medicine. Additionally, semen and vaginal fluids may be used in rituals associated with childcare and health care for children. Our survey indicated that the use of traditional medicine is associated with lower socioeconomic status.

CONCLUSIONS

Population-based studies are needed to evaluate the relationship between traditional behavioural and sociocultural practices, which involve exchange of saliva and other bodily fluids and risk of infectious disease.

The relationship between anti-HPV-16 IgG seropositivity and cancer of the cervix, anogenital organs, oral cavity and pharynx, oesophagus and prostate in a black South African population

Background

Human papillomavirus type 16 (HPV-16) infection is an important cause of cervical cancer, other anogenital cancers and, possibly, some oral and pharyngeal cancers. The association of HPV-16 with oesophageal and with prostate cancers has not been firmly established.

Methods

We analysed sera from 3,757 HIV seronegative black South Africans using an anti-HPV IgG enzyme-linked immunosorbent assay (ELISA). The subjects were recruited from 1995 to 2000 as part of an ongoing cancer case control study. Cases were patients with newly diagnosed cancers of the cervix (n = 946), other anogenital organs (n = 80), the oral cavity and pharynx (n = 102), the oesophagus (n = 369) or the prostate (n = 205). The comparison group consisted of 2,055 age and sex-matched patients randomly selected from the same data base, diagnosed at the same hospitals, but with a vascular disease or with a cancer unrelated to HPV infection. Subjects' sera were randomly and blindly allocated onto ELISA plates. Optical density (OD) levels of anti-HPV-16 IgG of > 0.45 and ≥ 0.767 were taken to be cut-offs for negative, medium and high antibody levels.

Results

After adjustment for potential confounders, cancer types that showed a statistically significant association with increased anti-HPV-16 IgG antibody (Ab) levels were cancer of the cervix (OR for medium Ab levels = 1.6, and for high = 2.4, p < 0.0001), cancers of other anogenital organs (OR for medium or high Ab levels = 2.5, p = 0.002), and cancer of the oesophagus (OR for medium Ab = 1.3, and high Ab levels = 1.6 p = 0.002). Cancers of the oral cavity and pharynx showed a borderline significant association in the unadjusted model (p = 0.05) but after adjustment for confounding the trend in relation to Ab levels was positive but not statistically significant (OR for medium Ab = 1.1, and high Ab = 1.5 p = 0.13). Prostate cancer was not associated with HPV-16 seropositivity (OR for medium Ab level = 1.4, and for high Ab level = 1.3, p = 0.3).

Conclusion

If there is indeed an association between HPV-16 and oesophageal and possibly also some oral cavity and pharyngeal cancers, then emerging HPV vaccines may also reduce, at least in part, the incidence of these leading cancer types.

Transmission of Kaposi Sarcoma-Associated Herpesvirus Between Mothers and Children in a South African Population

BACKGROUND

To assess whether Kaposi sarcoma-associated herpesvirus (KSHV) with or without HIV coinfection in South African mothers is associated with higher KSHV seropositivity in their children.

METHODS

We tested sera from 1287 South African children and 1179 mothers using assays for KSHV lytic K8.1 and latent ORF73 antigens. We computed odds ratios (ORs) and 95% confidence intervals (CIs) to assess associations between KSHV serostatus and risk factors.

RESULTS

KSHV seroprevalence was 15.9% (204 of 1287 subjects) in children and 29.7% (350 of 1179 subjects) in mothers. The risk of KSHV seropositivity was significantly higher in children of KSHV-seropositive mothers compared with those of KSHV-seronegative mothers. The HIV status of mothers was marginally associated with an increased risk of KSHV seropositivity in their children (OR = 1.6, 95% CI: 1.0 to 2.6; P = 0.07). KSHV seroprevalence was significantly higher in HIV-infected subjects (P = 0.0005), and HIV-infected subjects had significantly higher lytic and latent KSHV antibody levels than HIV-negative subjects.

CONCLUSIONS

The risk of acquisition of KSHV was higher among children of KSHV-seropositive mothers. Although KSHV seroprevalence was significantly higher in children and mothers who were infected with HIV, the HIV status of the mother was only marginally associated with an increased risk of KSHV seropositivity in the child.

Reactivation of Kaposi's sarcoma-associated herpesvirus by natural products from Kaposi's sarcoma endemic regions

Kaposi's sarcoma (KS) and its causative agent, Kaposi's sarcoma associated herpesvirus (KSHV/HHV-8), a gamma2 herpesvirus, have distinctive geographical distributions that are largely unexplained. We propose the "oncoweed" hypothesis to explain these differences, namely that environmental cofactors present in KS endemic regions cause frequent reactivation of KSHV in infected subjects, leading to increased viral shedding and transmission leading to increased prevalence of KSHV infection as well as high viral load levels and antibody titers. Reactivation also plays a role in the pathogenesis of KSHV-associated malignancies. To test this hypothesis, we employed an in vitro KSHV reactivation assay that measured increases in KSHV viral load in KSHV infected primary effusion lymphoma (PEL) cells and screened aqueous natural product extracts from KS endemic regions. Of 4,842 extracts from 38 countries, 184 (5%) caused KSHV reactivation. Extracts that caused reactivation came from a wide variety of plant families, and extracts from Africa, where KSHV is highly prevalent, caused the greatest level of reactivation. Time course experiments were performed using 28 extracts that caused the highest levels of reactivation. The specificity of the effects on viral replication was examined using transcriptional profiling of all viral mRNAs. The array data indicated that the natural extracts caused an ordered cascade of lytic replication similar to that seen after induction with synthetic activators. These in vitro data provide support for the "oncoweed" hypothesis by demonstrating basic biological plausibility.

Kaposi sarcoma-associated herpesvirus in non-Hodgkin lymphoma and reactive lymphadenopathy in Uganda

Kaposi sarcoma-associated herpesvirus (KSHV) causes Kaposi sarcoma and is also associated with primary effusion lymphoma, a subset of diffuse large B-cell lymphomas, and multicentric Castleman disease. Because KSHV infection is endemic in sub-Saharan Africa, we sought to identify cases of KSHV-positive non-Hodgkin lymphomas (NHLs) and reactive lymphadenopathy in this region. One hundred forty-four cases (80 NHLs, 64 reactive lymph nodes) from the major pathology laboratory in Uganda were reviewed. One NHL was KSHV-positive, as indicated by staining for the viral latent nuclear antigen. This NHL was a diffuse large B-cell lymphoma in a 5-year-old boy. The tumor was also Epstein-Barr virus-positive. In addition, 2 reactive lymph nodes, both classified histologically as follicular involution, stained KSHV latent nuclear antigen-positive and thus most likely represent multicentric Castleman disease. In all 3 KSHV-positive cases, a minority of cells expressed KSHV viral interleukin 6, a biologically active cytokine homolog. In conclusion, we show that KSHV is rarely associated with lymphoproliferative disorders in sub-Saharan Africa. We describe the first case of a KSHV-positive NHL from this region; this case is also the first reported pediatric lymphoma associated with KSHV infection.

Antibodies against six human herpesviruses in relation to seven cancers in black South Africans: a case control study

Background

Infections with certain human herpesviruses have been established as risk factors for some cancer types. For example, Epstein-Barr Virus is considered a cause of Burkitt's lymphoma and other immunosuppression related lymphomas, Hodgkin lymphoma, and nasopharyngeal cancer. Several other human herpesviruses have been linked to cancers but the totality of evidence is inconclusive.

Methods

We conducted a systematic sub-study from within an ongoing case control study of adult black South Africans to investigate the relationship between antibodies to six human herpesviruses and seven cancer groups that may be caused by infectious agents. Subjects had incident cancers of the oral cavity(n = 88), the cervix(n = 53), the prostate(n = 66), Hodgkin lymphoma(n = 83), non-Hodgkin lymphoma(n = 80), multiple myeloma(n = 94) or leukaemia(n = 203). For comparison, patients with other cancers(n = 95) or cardiovascular disease(n = 101) were randomly selected from within the study. Patients were interviewed and their blood was tested for IgG antibodies against HSV-1, HSV-2, VZV, EBV-EBNA, CMV and HHV-6 using enzyme linked immunosorbent assays. Because these viruses are highly prevalent in this population, optical density results from the assays were used as an indirect, quantitative measure of antibody level.

Results

There was significant variation in the mean log antibody measures for HSV-2, VZV, CMV and HHV-6 between the disease groups. However, none of the specific cancer groups had significantly higher mean log antibody measures for any of the viruses compared to either control group. In a more detailed examination of seven associations between cancers and herpesviruses for which there had been prior reports, two statistically significant associations were found: a decreasing risk of myeloid leukaemia and an increasing risk of oral cancer with increasing tertiles of antibodies against HHV-6 compared to all other patients (p-trend = 0.03 and 0.02, respectively). Odds ratios for the top tertile compared to the bottom tertile were 0.58 (95%CI 0.3 – 1.0) for myeloid leukaemia and 2.21 (95% CI 1.1 – 4.3) for oral cancer.

Conclusion

In this population, using these tests for IgG, neither mean antibody measure nor high antibody measure against human herpesviruses 1–6 was strongly associated with any of the seven cancer groups. However, we may not have had sufficient power to detect weak associations or associations with a sub-type of cancer if they were present.

A prospective study of Kaposi's sarcoma-associated herpesvirus and Epstein-Barr virus in adults with human immunodeficiency virus-1

Antibody titres against Kaposi's sarcoma associated herpesvirus (KSHV or human herpesvirus 8 (HHV-8)) and Epstein–Barr virus (EBV) were examined in people who subsequently developed Kaposi's sarcoma and non-Hodgkin's lymphoma, within randomised controlled trials of antiretroviral therapy in adults infected with the human immunodeficiency virus-1 (HIV). For each case of Kaposi's sarcoma (n=189) and each case of non-Hodgkin's lymphoma (n=67), which developed after randomisation, one control was randomly selected from other trial participants, after matching for age, sex, ethnicity, mode of HIV transmission, type of treatment received and period of follow-up. Using sera taken an average of two and a half years before the diagnosis of cancer, titres of antibodies against KSHV latent (LANA) and lytic (K8.1) antigens and against EBV (VCA) antigens were investigated in relation to subsequent risks of cancer by calculating odds ratios (OR) using conditional logistic regression. Latent antibodies against KSHV were detectable among 38% (72 out of 189) of Kaposi's sarcoma cases and 12% (23 out of 189) of their controls (OR=4.4, 95% confidence intervals (CI) 2.3–8.3, P<0.001). The OR for Kaposi's sarcoma increased with increasing antilatent KSHV antibody titre (χ²₁ for trend=32.2, P<0.001). Lytic antibodies against KSHV were detectable among 33% (61 out of 187) of Kaposi's sarcoma cases and 19% (36 out of 187) of their controls (OR=2.0, 95% CI 1.2–3.4, P=0.003) and the OR for Kaposi's sarcoma increased with increasing antilytic KSHV antibody titre (χ²₁ for trend=6.2, P=0.02). Virtually, all cases and controls had anti-EBV antibodies detected and the OR for non-Hodgkin's lymphoma associated with a doubling of the anti-EBV antibody titre was estimated to increase by a multiplicative factor of 1.3 (95% CI 0.9–1.7, P=0.1). Kaposi's sarcoma was not associated with antibody levels against EBV (P=0.4) and non-Hodgkin's lymphoma was not associated with antibodies against KSHV (latent P=0.3; lytic P=0.5). Adjustment for CD4 count at the time of sample collection made no material difference to any of the results. In conclusion, among human immunodeficiency virus infected people, high levels of antibodies against KSHV latent and lytic antigens are strongly associated with subsequent risk of Kaposi's sarcoma but not non-Hodgkin's lymphoma. Antibody titre to EBV does not appear to be strongly associated with subsequent risk of Kaposi's sarcoma or non-Hodgkin's lymphoma in HIV infected people.

Epidemiology of Kaposi's Sarcoma herpesvirus (HHV8) in Västerbotten county, Sweden

A population-based serosurvey of Human Herpesvirus type 8 (HHV8) in Västerbotten County, an area of Northern Sweden with high incidence of Kaposi's Sarcoma, was conducted. Serum samples from an age- and sex-stratified random sample of 520 subjects (260 men and 260 women) participating in a population-based biobanking project were tested for antibodies against HHV8, using a sensitive indirect immunofluorescence assay to latent and lytic HHV8 antigens. Buffy coat DNA was also analyzed for viral DNA using real time PCR assay. HHV8 DNA was not detectable in any one of the buffy coat samples. Eighty-four subjects (16.2%) were HHV8 seropositive, 14.4% for the lytic HHV8 antigen, and 1.7% for the latent HHV8 antigen. HHV8 seroprevalences were not associated significantly with sex or age. HHV8 seropositivity was more common among smokers (OR: 1.95, 95% CI: 1.02-3.75), but was less common among consumers of wine and spirits (OR: 0.44, 95% CI: 0.25-0.77 and OR: 0.50, 95% CI: 0.26-0.95, respectively). In summary, HHV8 has an intermediate high and stable seroprevalence rate in Northern Sweden, but environmental determinants that can explain the viral distribution were not found.

Ugandan Kaposi's sarcoma-associated herpesvirus phylogeny: evidence for cross-ethnic transmission of viral subtypes

OBJECTIVE

The aim of this study was to test the relationship between Kaposi's sarcoma-associated herpesvirus (KSHV) phylogeny and host ethnicity at the within-country scale.

METHODS

KSHV genomic DNA samples were isolated from 31 patients across eleven Ugandan ethnic groups. Amino acid sequences of the ORF-K1 gene were used to construct a neighbor-joining phylogenetic tree.

RESULTS

A5 and B1 variants predominated with no evidence of distinct ethnic or geographic distribution. A new K1 subtype (F) was identified in a member of the Bantu Gisu tribe and a new subtype B variant (B3) among members of the Bantu Ganda tribe.

CONCLUSIONS

The phylogeny may yet be structured by host ethnicity if members of Ugandan groups have convoluted biological origins, even as they identify with single tribes. An alternative possibility is that KSHV subtype evolution may have preceded major diversification of sub-Saharan Africans into ethnicities as we know them today, with ethnic groups beginning their histories already hosting multiple subtypes. A third alternative is that horizontal transmission of multiple KSHV subtypes may have broken up vertical lineages of the virus passed down within Ugandan populations.

Kaposi's sarcoma risk among transplant recipients in the United States (1993–2003)

Kaposi's sarcoma (KS) risk is high in immunosuppressed transplant recipients. KS develops in recipients with pre-existing infection with human herpesvirus 8 (HHV-8), the causative agent for KS, but it can also occur in recipients infected by donors. The relative importance of these sources of infection in recipients in the United States is unknown. We report recipient and donor characteristics associated with KS among transplant recipients in the United States. KS risk, after solid organ transplantation during 1993-2003, was analyzed using data from the Organ Procurement and Tissue Network. Associations were determined using proportional hazards regression. Sixtyfive KS cases were identified among 234,127 transplants (incidence 8.8 per 100,000 person-years). Most cases occurred in the first 2 years after transplantation (incidence 12.5 per 100,000 person-years). KS risk increased steadily with recipient age (p(trend) < 0.001) and was associated with the recipient being male (HR 1.8, 95% CI, 1.0-3.2), Hispanic (2.1, 1.1-3.8) and a non-U.S. citizen (3.9, 1.8-8.6). Mismatch at the HLA-B locus, but not at HLA-A or HLA-DR loci, was associated with heightened risk (HR 3.6, 95%CI 1.1-11 for 1-2 vs. 0 HLA-B mismatches). KS was unrelated to donor characteristics and was not significantly related to use of specific antirejection medications. Our study found that KS incidence was low among transplant recipients in the United States, but it was associated with recipient age, sex and citizenship, perhaps reflecting pre-existing HHV-8 infection. The high KS risk immediately posttransplant and in persons with HLA-B mismatch highlights the role of immunosuppression and/or immune stimulation in KS pathogenesis.

Oral malignant neoplasia: a survey of 428 cases in two Zimbabwean hospitals

A review of oral malignant neoplasms biopsies accessioned in the pathology services of Harare Central Hospital and Parirenyatwa Hospital, Harare, Zimbabwe, during the 10year period January 1982 to December 1991 was carried out. Clinical records of 428 patients with histologically diagnosed oral malignant neoplasms by ICD-O type and site (COO.O-CO6.9) were retrieved and analyzed for gender, age, history of tobacco and alcohol usage, neoplastic type and histologic differentiation of squamous cell carcinoma (8000/3). Oral malignant neoplasms constituted 24.8% (n = 428) of the 1723 biopsies accessioned in the department during this period. There was a male to female ratio of 1.9:1, with lesions being most common in the 41-60 year age group. Squamous cell carcinoma, (8070/3) 73.1%, was the predominant oral malignancy most common in the 61-70 year age group with 21.1% on the mandibular gingivae (CO3.1), 20.5% on the tongue (CO1.9-CO2.9), 18.5% on the floor of the mouth (CO4.9) and 10.5% each on the maxillary gingivae (CO3.O) and buccal mucosa (CO6.O). The hard palate (CO5.9) had 9% of the lesions. Lip malignancy (COO-COO.9 and C44.0), inclusive of mucosa of lip, vermilion and skin, constituted 3.3% and minor salivary gland (CO6.9) malignancy (M-8940/3) 4.9%. The remaining oral malignancies, 11%, included Burkitt's lymphoma (M-9687/3) 4.7%; Kaposi's sarcoma (M-9140/3) 3.7%; osteosarcoma (M-9180/3) 2.6% and malignant melanoma (M-8720/3) 1.9%. Fourty five percent of the patients admitted tobacco and alcohol consumption, of whom 95% were males. Oral malignant neoplasms were more common in males than females and occurred in a relatively young age group. Well-differentiated squamous cell carcinoma (M-8070/31) was the most common oral malignant neoplasm and was most frequently found on the mandibular gingivae (CO3.1), tongue (CO1.9-CO2.9) and floor of the mouth (CO4.9). The lip (COO-COO.9) was least affected with a high palatal (CO5.9) involvement.

AIDS-related Kaposi's sarcoma: epidemiological, diagnostic, treatment and control aspects in sub-Saharan Africa

Until the 1980s, little attention had been accorded to endemic Kaposi's sarcoma (KS), a neoplasm noted in several parts of Southern Europe and the African continent but with relatively slow progression, except in children and young adults. Furthermore, therapeutic approaches based on surgery, radiation and topical treatment were of limited efficacy, mostly used to overcome the disabling and stigmatizing effects of the disease. With the emergence of the HIV/AIDS epidemic, and the profound impact of KS on AIDS-related mortality, the pathogenesis of KS has been better studied, and the realisation that a virus (KS-associated Herpesvirus or Human Herpesvirus 8, or KSHV/HHV-8), combined with immunosuppression and cytokine-induced growth, was responsible for the development of this disease has led to novel therapeutic approaches. These are unfortunately still highly toxic, require careful monitoring, and are expensive, thus limiting their use in most parts of Africa. However, the use of highly active antiretroviral therapy (HAART), which has led to a considerable decline in KS incidence in populations of industrialized countries, constitutes the best hope for the control of this stigmatizing and lethal disease in Africa. Trials comparing different regimens of antiretroviral drugs in combination with systemic chemotherapeutic agents are urgently needed.

Human herpesvirus 8--a novel human pathogen

In 1994, Chang and Moore reported on the latest of the gammaherpesviruses to infect humans, human herpesvirus 8 (HHV-8) [1]. This novel herpesvirus has and continues to present challenges to define its scope of involvement in human disease. In this review, aspects of HHV-8 infection are discussed, such as, the human immune response, viral pathogenesis and transmission, viral disease entities, and the virus's epidemiology with an emphasis on HHV-8 diagnostics.

Kaposi's sarcoma-associated herpesvirus: clinical, diagnostic, and epidemiological aspects

Kaposi's sarcoma-associated herpesvirus (KSHI) is one of the few viruses proven to be associated with tumorigenesis in humans. Its causal association with all clinical and epidemiological variants of Kaposi's sarcoma (KS) is well established. KSHV is also involved in the pathogenesis of primary effusion lymphoma (PEL) and a subset of multicentric Castleman's disease (MCD). Possible associations of KSHV with other clinical settings have been extensively examined. The findings from several of these studies are contradictory and are yet to be resolved. Concentrated effort over the last decade, since the initial discovery of KSHV, led to the development of several experimental systems that resulted in a better comprehension of the biological characteristics of KSHV and set the stage for the understanding of mechainisms by which diseases are induced by the virus. The development of molecular, histological, and serological tools for KSHV diagnosis allowed researchers to track the transmission and to study the epidemiology of KSHV. These assays have been applied, in particular in ambiguous cases, in order to confirm clinically and pathologically based diagnoses. Here, we review the advances in the clinical, experimental, diagnostic, and epidemiological research of KSHV.

Kaposi's sarcoma in kidney transplant recipients: a 23-year experience

BACKGROUND

Kaposi's sarcoma (KS) is a relatively common malignancy after kidney transplantation, accounting for up to 80% of all malignancies in developing countries.

AIM

To assess the frequency of KS in renal transplant recipients, and determine the impact of demographic factors, immunosuppression and treatment options.

DESIGN

Retrospective study in a single centre in South Africa.

METHODS

Charts and pathology reports of 542 recipients of 623 kidney allografts treated at our institution between 1976 and 1999 were reviewed.

RESULTS

After a mean follow-up of 6.4 years, 21 (3.9%) recipients had KS, representing 47.7% of all post-transplant malignancies. KS accounted for more post-transplant cancers in non-White than White patients (79.1% vs. 11.7%, p < 0.001). KS was equally common in males and females, and was not more frequent under cyclosporine. Skin involvement was universal; visceral disease occurred in six patients (28.6%). Sixteen (94.1%) patients with limited skin disease and two (100%) with superficial nodal disease responded to withdrawal or reduction of immunosuppression. Renal function was preserved when immunosuppression was reduced instead of withdrawn (p = 0.02). Patients with vital organ involvement succumbed rapidly to KS. Post-mortem examination revealed more extensive disease than was suspected clinically.

DISCUSSION

Ethnic differences exist in the frequency of KS in patients residing in the same geographical area. Since withdrawal results in graft loss, reducing immunosuppression should be first-line treatment for patients with disease limited to skin, and possibly for disease of the superficial lymph nodes. The malignant behaviour of KS, and extent of pathological involvement, cast doubt on the idea that KS is a hyperplasia rather than a true malignancy.

New developments in IL-6 dependent biology and therapy: where do we stand and what are the options?

Interleukin-6 (IL-6) is a four-helical protein which, on target cells, binds to a specific IL-6-receptor and two molecules of the promiscuous signal transducing protein gp130. Structure-function analysis defined three molecular contact sites between IL-6 and its receptor subunits. Using this information, competitive antagonistic proteins as well as hyperagonistic proteins were developed. Possible therapeutic applications of IL-6 antagonists are in IL-6 dependent haematological disorders (Castleman's disease, POEMS syndrome, multiple myeloma) and bone diseases (Paget's disease, osteoporosis). Designer IL-6 antagonists could suppress inflammatory activity in rheumatic and autoimmune diseases and could prevent secondary amyloidosis. IL-6 antagonists could also prove advantageous in myocardial infarction and unstable angina pectoris. IL-6 antagonists might slow down development of (mesangioproliferative) glomerulonephritis. On the other hand, hyperagonistic variants of IL-6 have a potential in ex vivo expansion of bone marrow stem cells and as thrombopoietic agents. They might also be developed into drugs to support liver regeneration in vivo and to treat stress-induced cardiac insufficiency.

Seroprevalence of human herpesvirus 8 infection in children born to HIV-1- infected women in São Paulo, Brazil

Human herpesvirus-8 (HHV-8) appears to be transmitted mainly by sexual contact. However, several studies suggest that in developing countries the infection may be acquired early in life by routes other than sexual transmission. The present study estimated the seroprevalence of HHV-8 in Brazilian children born to HIV-1-infected mothers. The serum samples were collected in a cross-sectional cohort study from 99 children born to HIV-infected mothers (median age 3.27 years; range 1.5-13.8 years) attending the outpatient clinic of the Federal University of Sao Paulo. IgG antibodies to HHV-8 latency-associated nuclear antigen and lytic phase antigens were detected by immunofluorescence assays. The samples tested were collected from children aged 12 months or older to exclude the possibility of cross-placental antibody transport. The total prevalence of anti-lytic antibodies in this population (5/99; 5%) reveals that HHV-8 infection can occur during childhood. Children aged 1.5 to 2 years had a seroprevalence of 2% (1/50) and children aged 3.25 to 13.8 years had a seroprevalence of 8% (4/49). This difference was not statistically significant, probably because of the small size of the sample, but it suggests that HHV-8 infection occurs more commonly late in infancy. Further prospective studies are necessary to evaluate the timing and risk factors for primary HHV-8 infection in the pediatric population.

Human herpesvirus 6 activates lytic cycle replication of Kaposi's sarcoma-associated herpesvirus

Kaposi's sarcoma-associated herpesvirus (KSHV) or human herpesvirus 8 (HHV-8) is a gamma-herpesvirus consistently identified in Kaposi's sarcoma (KS), primary effusion lymphoma, and multicentric Castleman's disease. KSHV infection appears to be necessary, but not be sufficient for development of KS without other co-factors. However, factors that facilitate KSHV to cause KS have not been well defined. Because patients with KS are often immunosuppressed and susceptible to many infectious agents including human herpesvirus 6 (HHV-6), we investigated the potential of HHV-6 to influence the replication of KSHV. By co-culturing HHV-6-infected T cells with KSHV-latent BCBL-1 cell line, infecting BCBL-1 cells with HHV-6 virions, and generating heterokaryons between HHV-6-infected T cells and BCBL-1 cells, we showed that HHV-6 played a critical role in induction of KSHV replication, as determined by production of lytic phase mRNA transcripts and viral proteins. We confirmed and extended the results by using a luciferase reporter assay in which KSHV ORF50 promoter, the first promoter activated during KSHV replication, drove the luciferase expression. Besides HHV-6, we also found that cytokines such as interferon-gamma partially contributed to induction of KSHV replication in the co-culture system. These findings suggest that HHV-6 may participate in KS pathogenesis by promoting KSHV replication and increasing KSHV viral load.

Human Herpesvirus 8 (HHV-8) Infection in HIV/AIDS Patients From Santos, Brazil: Seroprevalence and Associated Factors

GOAL

The goal of this study was to evaluate the seroprevalence of human herpesvirus 8 (HHV-8) infection among HIV-infected individuals from Brazil and the associated risk factors.

STUDY

A cross-sectional survey was carried out with 497 HIV/AIDS outpatients attending the local AIDS Reference Center in Santos (southeastern Brazil) between February 1997 and January 1998 had serum samples screened for anti-HHV-8 antibodies. Patients were considered seropositive whenever reactivity was observed in at least 1 of 3 tests (immunofluorescence assays for latent nuclear and lytic antigens and orf65 recombinant antigen enzyme-linked immunosorbent assay).

RESULTS

Overall HHV-8 seroprevalence was 13.9% (95% confidence interval [CI], 10.9-17.6). HHV-8 coinfection was significantly more frequent in men (18.7%; 95% CI, 14.1-23.4) than in women (7.8%; 95% CI, 4.2-11.3) (P < 0.001). According to the mode of HIV acquisition among males, seroprevalence of HHV-8 infection was significantly higher in men who have sex with men when compared with the other groups (32.4% vs. 10.0%, P < 0.001). Multivariate logistic regression revealed HHV-8 infection among men to be independently associated with sexual orientation (adjusted odds ratio [AOR], 5.5 for homosexuals; AOR, 2.8 for bisexuals). No significant risk factor for HHV-8 infection could be demonstrated for HIV-infected women in this cohort,

CONCLUSIONS

This study provides further evidence that men who have sex with men are at higher risk of HHV-8 infection and shows that the epidemiologic pattern of this infection among HIV/AIDS patients from Santos, Brazil, is similar to that described in other countries with a low incidence of Kaposi's sarcoma.

Increased seroprevalence of human herpesvirus 8 in patients with hematological disorders

Human herpesvirus 8 (HHV8) has been consistently linked to Kaposi's sarcoma and many hematological diseases such as pleural effusion lymphoma, multicentric Castleman's disease, some lymphoproliferative diseases and posttransplantation bone marrow failure. However, whether patients with hematological disorders are at a higher risk of HHV8 infection has not been determined. In this study, indirect immunofluorescence was used to detect antibodies against lytic antigens of HHV8 in 265 patients with hematological disorders. Our data showed that 24.5% of patients (65/265) were seropositive for HHV8 IgG antibody, which was significantly higher than in our general population (p < 0.001). A significantly higher seropositive rate can be found in patients with lymphoma, leukemia, autoimmune cytopenias and myeloproliferative disorders, but not in patients with myeloma or aplastic anemia. No difference in the seropositive rate is associated with gender or age. We conclude that some patients with hematological disorders are at a higher risk of HHV8 infection.

Prostate carcinogenesis and inflammation: emerging insights

Prostate cancer remains a significant health concern for men throughout the world. Recently, there has developed an expanding multidisciplinary body of literature suggesting a link between chronic inflammation and prostate cancer. In support of this hypothesis, population studies have found an increased relative risk of prostate cancer in men with a prior history of certain sexually transmitted infections or prostatitis. Furthermore, genetic epidemiological data have implicated germline variants of several genes associated with the immunological aspects of inflammation in modulating prostate cancer risk. The molecular pathogenesis of prostate cancer has been characterized by somatic alterations of genes involved in defenses against inflammatory damage and in tissue recovery. A novel putative prostate cancer precursor lesion, proliferative inflammatory atrophy, which shares some molecular traits with prostate intraepithelial neoplasia and prostate cancer, has been characterized. Here, we review the evidence associating chronic inflammation and prostate cancer and consider a number of animal models of prostate inflammation that should allow the elucidation of the mechanisms by which prostatic inflammation could lead to the initiation and progression of prostate cancer. These emerging insights into chronic inflammation in the etiology of prostate carcinogenesis hold the promise of spawning new diagnostic and therapeutic modalities for men with prostate cancer.

Repeated measures study of human herpesvirus 8 (HHV-8) DNA and antibodies in men seropositive for both HHV-8 and HIV

OBJECTIVE

To study the natural history and pathogenesis of human herpesvirus 8 (HHV-8) infection in HHV-8-seropositive, immunosuppressed men.

DESIGN

Longitudinal study of 87 HHV-8- and HIV-seropositive men [42 with Kaposi's sarcoma (KS)] during four visits over a 2 month period.

METHODS

: Patients provided oral fluid and blood. HHV-8 antibody titers were measured with peptide-based enzyme-linked immunosorbent assays (ELISA) for ORF65 and K8.1; HHV-8 DNA was detected with polymerase chain reaction ELISA.

RESULTS

HHV-8 DNA was present in oral fluid or peripheral blood mononuclear cells (PBMC) at one or more of the four visits in 71% of men with KS and 56% of men without KS. The strongest correlate of HHV-8 DNA in PBMC was the presence of KS [odds ratio (OR), 8.7; 95% confidence interval (CI), 3.4-22]. Detection of HHV-8 DNA in oral fluid or PBMC was often intermittent, but individuals who shed virus at one time point were more likely to shed at other times. Some men had incomplete epitope recognition in their anti-HHV-8 antibody response. High antibody titers were associated with the absence of circulating HHV-8, particularly for the ORF65 seroassay (OR, 0.16; 95% CI, 0.05-0.51).

CONCLUSIONS

Among HHV-8 seropositive men, circulating virus is common even in the absence of disease. The link between KS and HHV-8 DNA in PBMC suggests that anti-herpes drugs may impede KS development or progression. Seroassays should target multiple epitopes to achieve maximal sensitivity. HHV-8 replication may be limited by high antibody titers or other immune function for which antibodies are a marker.

AIDS-associated cancer in developing nations

PURPOSE OF REVIEW

With the emergence of the highly active antiretroviral therapy era, it is apparent that the incidence of Kaposi sarcoma, in particular, and lymphoma in patients with AIDS is declining, especially in regions of the world where these regimens are routinely available. The burden of HIV infection and AIDS is greatest in the developing world, and no doubt neoplastic complications are increasingly encountered. The purpose of this review is to highlight recent developments of this aspect of the AIDS epidemic in the developing world.

RECENT FINDINGS

It was readily apparent that the incidence of Kaposi sarcoma sharply increased after the onset of the AIDS epidemic in developing countries. By the end of the second decade of the epidemic, non-Hodgkin lymphoma is increasing in incidence and the natural history of Burkitt lymphoma is evolving in the backdrop of HIV infection as well. Cervical cancer is the most common cancer in women in many developing countries, yet the true impact of HIV infection on the development of this neoplasm is not fully understood. Squamous cell carcinoma of the conjunctiva appears to be a unique AIDS-associated neoplasm that is encountered in sub-Saharan Africa as well. Finally, although the epidemiologic and clinicopathologic features for many AIDS-associated neoplasms are well characterized in developing regions of the world, there is a paucity of data on the therapeutic approach to these tumors in this setting.

SUMMARY

It is apparent that as the AIDS pandemic proceeds, the burden of neoplastic diseases is increasing in developing nations. Current therapeutic approaches are not well documented. Pragmatic prevention and therapeutic interventions suitable for the resource-constrained setting are clearly needed.

Risk of malignant lymphoma associated with human herpesvirus-8: a case-control study in Spain

No overall increased risk of lymphoma associated with antibodies to human herpesvirus-8 was found in 526 lymphomas and 599 controls (odds ratio (OR)=1.04, 95% confidence interval (CI)=0.62–1.75); significant increases were noted for 19 lymphoplasmacytic lymphomas (OR=4.47, 95% CI=1.34–14.85) and nine low-grade lymphoma/lymphoma B-cell NOS (OR=5.82, 95% CI=1.07–31.73).

Human herpesvirus 8 seroconversion in Kenyan women by enzyme-linked immunosorbent assay and immunofluorescence assay

BACKGROUND

Human herpesvirus 8 (HHV-8) antibody tests vary in reported sensitivity and specificity, depending on the population tested and the assay.

OBJECTIVE

The purpose of this study was to compare the ability to detect seroconversion to HHV-8 in a cohort of HHV-8 seronegative female commercial sex workers in Kenya using three tests: HHV-8 viral lysate-based enzyme-linked immunosorbent assay (ELISA), an immunofluorescence assay for HHV-8 lytic antigens (IFA-lytic) and IFA for latent nuclear antigens (IFA-LANA).

STUDY DESIGN

By ELISA, 16 women from a prospective cohort of commercial sex workers were identified as seroconverting to HHV-8. A total of 124 post-enrollment samples from these 16 women as well as the enrollment samples were tested for HHV-8 antibodies by all three assays to monitor seroconversion.

RESULTS

Of 16 women with apparent seroconversion by ELISA, 8 had a rise in IFA-lytic titers either concomitant with or prior to the first positive ELISA sample and no initial LANA by IFA. Five of the 16 women were IFA-LANA positive at entry, indicating prior infection with HHV-8. Three women had no evidence of seroconversion by either IFA-lytic or IFA-LANA and two of these three had increased ELISA reactivity concomitant with HIV-1 infection.

CONCLUSIONS

Conversion from a negative to a positive ELISA result for HHV-8 antibody indicated seroconversion in only half of the study cohort of 16 women when IFA-lytic and IFA-LANA results were considered. The IFA-lytic assay was more sensitive than ELISA for early antibody responses. The IFA-LANA was positive in some women who had neither IFA-lytic nor ELISA antibodies suggesting it may be a marker for latent infections. Presumptive identification of incident HHV-8 infection by ELISA screening followed by IFA-lytic testing to confirm the positive test and IFA-LANA to rule out prior infection provides the most accurate documentation of HHV-8 seroconversion.

Antibodies against human herpesvirus 8 in South African renal transplant recipients and blood donors

OBJECTIVE

To examine the seroprevalence of human herpesvirus 8 (HHV-8) antibodies in a selected group of renal transplant recipients and blood donors, in relation to various socio-demographic variables.

SUBJECTS

Anonymised serum samples were obtained from 306 black donors attending blood donations at the SA National Blood Transfusion Service, Johannesburg, and 430 recipients of renal transplants at Johannesburg General Hospital, from 1998 to 1999.

METHODOLOGY

Serum samples were tested by indirect immunofluorescence assay to detect IgG antibodies against HHV-8. Crude and adjusted seroprevalence, and odds ratios were calculated to examine the relationship between antibodies to HHV-8 and age, sex, population, and risk group.

RESULTS

Adjusted HHV-8 seroprevalence at 'medium to high' antibody titres (at least 1:51,200) increased with age, from 2% (age 15-24; 95% CI=0.7-5.2) to 10% (age 45+; 95% CI=6.3-15.2). Whites had the lowest % adjusted seroprevalence (1.8; 95% CI:0.8-4.2), followed by blacks (7.4; 95% CI=5.1-10.8), Asians/Indians (9.5; 95% CI=3.6-22.9), and individuals of mixed race (12.5; 95% CI=4.5-30.2). Seroprevalence was not related to gender, or to occupation of blood donors. HHV-8 seroprevalence did not differ significantly between first-time blood donors, repeat donors, and transplant recipients (P=0.49). Transplant recipients had a greater proportion of persons with high HHV-8 antibody intensity; however, this difference was statistically not significant (P=0.08).

CONCLUSIONS

Blood donors and renal transplant patients had relatively high HHV-8 antibody titres. Given the strong association between HHV-8 seropostivity and the risk of developing Kaposi's sarcoma, it may be prudent in settings where HHV-8 seroprevalence is high to screen for HHV-8 in donated blood used for these immunocompromised individuals.

Antiretroviral Treatment Regimens and Immune Parameters in the Prevention of Systemic AIDS-Related Non-Hodgkin's Lymphoma

Purpose

Immunosuppression induced by HIV-1 increases the risk of developing non-Hodgkin's lymphoma (NHL). We measured the influence of immunologic factors and highly active antiretroviral therapy (HAART) on this risk. As there are no data demonstrating that specific antiretroviral regimens are effective at protecting from NHL, we compared different HAART regimens.

Patients and Methods

The protective effect of HAART regimens, containing protease inhibitors (PI) and/or non-nucleoside reverse transcriptase inhibitors (NNRTIs) on the development of NHL was examined in a prospectively recorded cohort of 9,621 HIV-infected individuals. Lymphocyte and natural killer subset data were also entered in univariate and multivariate analyses to establish and stratify the risk of NHL.

Results

From this cohort of 9,621 patients, 102 have been diagnosed with systemic AIDS-related NHL since 1996, when HAART became freely available here. By univariate analysis, increased age, higher nadir CD4 and CD8 T-cell counts, CD19 B-cell count, CD16/56 natural killer count and exposure to NNRTI or PI containing HAART conferred significant protection against NHL (P < .05). In a multivariate analysis, age, nadir CD4 and CD8 T-cell counts, and exposure to HAART were independent predictors of risk of NHL (P < .02). NNRTI-based HAART (adjusted rate ratio, 0.4; 95% CI, 0.3 to 0.5) was as protective as PI-based HAART, and these were significantly more protective than nucleoside analogues alone (rate ratio, 0.5; 95% CI, 0.4 to 0.7) or no antiretrovirals (P < .001).

Conclusion

Effective HAART-induced maintenance of CD4 and CD8 counts protects from systemic AIDS-related NHL.

Oral Kaposi's sarcoma: a clinicopathologic study from South Africa

OBJECTIVES

In this retrospective study, we defined the clinicopathologic characteristics of oral Kaposi's sarcoma (KS) and determined the presence of human herpesvirus 8 in the oral lesions in a group of South African patients. These results were compared with similar data from patients in developed countries.

STUDY DESIGN

Eighty-one cases of oral KS were retrieved from the departmental archives. Fourteen patients with oral pyogenic granuloma served as control subjects. DNA was extracted by using a modified phenol chloroform extraction method and amplified by using polymerase chain reaction. If beta-globin DNA sequences could not be demonstrated, the patient was excluded from the study.

RESULTS

Of the 81 patients included in the study, 68 (84%) had been diagnosed since 1997. Oral KS was often the first presenting sign of human immunodeficiency virus infection. Some of the lesions exceeded 4 cm in diameter. The most commonly affected site was the palate (37 patients), followed by the tongue and gingiva. Multiple oral sites were frequently involved. The mean age of the patients was 34.7 years (range, 2-58 years). The male-to-female ratio was 1.31 to 1. Most of the patients (94%) were black. Human herpesvirus 8 DNA sequences were detected in 44 of the 45 cases of oral KS in which the DNA was analyzed, and in 1 case of pyogenic granuloma.

CONCLUSIONS

The only significant clinicopathologic differences in findings between our study and previous studies in developed countries were (1) the male-to-female ratio, (2) the preponderance of black patients, and (3) the more frequent involvement of the tongue. There are no studies reporting the clinicopathologic characteristics of oral KS in populations of developing countries.

Epidemiology of inflammation and prostate cancer

PURPOSE

We provide an overview of some of the basic, clinical and epidemiological research that has been conducted to investigate the potential role of chronic inflammation in prostate carcinogenesis and to provide direction for future research on this hypothesis.

MATERIALS AND METHODS

We reviewed the literature on this topic.

RESULTS

Chronic inflammation has long been linked to cancers with an infectious etiology, such as stomach, liver and colon cancer, in patients with inflammatory bowel disease. Whether intraprostatic inflammation contributes to prostate carcinogenesis is unknown. Inflammation is frequently present in prostate biopsies, radical prostatectomy specimens and tissue resected for treatment of benign prostatic hyperplasia. Also, inflammatory infiltrates are often found in and around foci of atrophy that are characterized by an increased proliferative index. These foci, called proliferative inflammatory atrophy, may be precursors of early prostate cancer or may indicate an intraprostatic environment favorable to cancer development. Epidemiological studies have indirectly examined the role of chronic inflammation in prostate carcinogenesis through studies of pro-inflammatory and anti-inflammatory factors. When taken together studies of sexually transmitted infections, clinical prostatitis, and genetic and circulating markers of inflammation and response to infection hint at a link between chronic intraprostatic inflammation and prostate cancer.

CONCLUSIONS

Additional well-designed basic, clinical and epidemiological studies are needed to resolve questions about the role of chronic inflammation in prostate carcinogenesis and to determine if intraprostatic inflammation is a rational target for chemoprevention.

Chemokine receptor–8 (CCR8) mediates human vascular smooth muscle cell chemotaxis and metalloproteinase-2 secretion

The response of the arterial vascular wall to injury is characterized by vascular smooth muscle cell (VSMC) migration, a process requiring metalloproteinase production. This migration is induced by cytokines, however the agonists involved are not fully defined. The CC chemokine receptor 8 (CCR8) is expressed on monocytes and T lymphocytes and is the sole receptor for the human CC chemokine 1 (CCL1, I-309) and for the viral chemokine, vCCL1 (viral macrophage inflammatory protein 1 [vMIP-1]). We have reported that CCR8 is expressed on human umbilical vein endothelial cells (HUVECs) and mediates chemotaxis induced by CCL1. The conditioned medium from incubation mixtures of lipoprotein(a) (Lp(a)) and HUVECs (LCM) contained CCL1 and stimulated both monocyte and HUVEC chemotaxis, providing novel mechanisms for the atherogenicity of Lp(a). We now report that CCL1, vCCL1, and LCM stimulate chemotaxis of human VSMCs that is blocked by murine monoclonal antibody against CCR8 and by the G-protein inhibitor pertussis toxin. The effect of anti-CCR8 was specific, as this antibody failed to effect the chemotaxis of VSMCs in response to CCL3 or by platelet-derived growth factor BB (PDGF-BB). VSMCs contained CCR8 mRNA and CCR8 antigen coprecipitated with VSMC membranes. Antibodies against metalloproteinase-2 (MMP-2) inhibited the CCL1-induced chemotaxis of VSMCs, whereas anti–MMP-9 was less effective. CCL1 induced VSMC pro–MMP-2 mRNA and protein secretion. Poxvirus MC148 inhibited the increase in MMP-2 induced by CCL1, documenting that CCR8 was the receptor responsible. In mouse femoral arteries, CCR8 and TCA3 antigen colocalized with VSMCs and were up-regulated after injury. The induction of CCR8 and CCL1/TCA3 under conditions associated with VSMC proliferation and migration raises the possibility that CCR8 may play an important role in vessel wall pathology.

Epidemiological characteristics of human herpesvirus-8 infection in a large population of antenatal women in Zambia

Comprehensive data describing epidemiological characteristics of the human herpesvirus-8 or Kaposi's sarcoma-associated herpesvirus (HHV-8 or KSHV) infection among pregnant women in a central sub-Saharan Africa are not available. This study determined virus prevalence estimates and the risk factors associated with HHV-8 infection. Cross-sectional, enrollment visit data were analyzed from a prospective cohort study of perinatal transmission of HHV-8 in Lusaka, Zambia. Exposure data were obtained via structured interview, physical examination, medical chart review, and laboratory testing. Among 3,160 antenatal women serologically screened for HHV-8 between September 1998 and October 2000, 40.2% were seropositive. The HHV-8 positive women were more likely to be co-infected with HIV-1 than those who were HHV-8 negative (34% vs. 26%; P < 0.0001). Of 154 variables evaluated by logistic regression analyses, only three risk factors, have emerged as independent predictors of HHV-8 positive serology: diagnosis of genital warts, HIV-1 co-infection and primary education. The association of HHV-8 infection with genital warts and HIV-1 co-infection suggests heterosexual transmission of HHV-8. HIV-1 infection may also act as a marker for particular behaviors, which could be sexual in nature, that are associated with both HIV-1 and HHV-8 transmission. Since HHV-8 facilitates development of AIDS-related Kaposi's sarcoma (KS), the results of this study could be utilized to identify specific population groups of pregnant women who are at increased risk for this disease.

Correlates of human herpes virus-8 and herpes simplex virus type 2 infections in Northern Cameroon

The association between sexual activity and human herpes virus-8 (HHV-8) infection has been established, but the mode of acquisition is still unclear. Blood samples from 238 individuals from Northern Cameroon were tested to evaluate the incidence of herpes simplex virus-2 (HSV-2), human immunodeficiency virus (HIV), Treponema pallidum, and HHV-8 infections and to identify their possible association. The presence of HSV-2 antibodies was associated significantly with gender, age, and HIV, HHV-8 antilatent, and T. pallidum antibodies, but not with HHV-8 antilytic antibodies. In a multivariate model older age, female gender, seropositivity for HIV, for HHV-8 latent antigens and for T. pallidum were associated independently with seropositivity for HSV-2. HSV-2-seropositive individuals had significantly higher titers of antibodies to both lytic (P = 0.019) and latent (P = 0.021) HHV-8 antigens. These results suggest that HSV-2 infection can contribute to sexual transmission of HHV-8 infection.