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Original Article

Antibodies against Human Herpesvirus 8 in Black South African Patients with Cancer

Freddy Sitas, D.Phil., Henri Carrara, M.P.H., Valerie Beral, F.R.C.P., Rob Newton, M.B., B.S., D.Phil., Gillian Reeves, Ph.D., Diana Bull, Ute Jentsch, M.B., B.Ch., M.Med., Rosana Pacella-Norman, Ph.D., Dimitra Bourboulia, M.Sc., Denise Whitby, Ph.D., Chris Boshoff, M.R.C.P., Ph.D., Moosa Patel, F.C.P.(S.A.), M.Med., Paul Ruff, M.B., B.Ch., M.Med., Werner R. Bezwoda, F.C.P., Ph.D., Edna Retter, L.M.C., Martin Hale, M.B., Ch.B., F.C.Path., and Robin Weiss, F.R.S.

N Engl J Med 1999; 340:1863-1871June 17, 1999

Abstract

Background

Infection with human herpesvirus 8 (HHV-8) has been consistently linked to Kaposi's sarcoma, but its mode of transmission, association with other cancers, and interaction with the human immunodeficiency virus type 1 (HIV-1) are largely unknown.

Methods

Between January 1992 and December 1997, we interviewed 3591 black patients with cancer in Johannesburg and Soweto, South Africa. Blood was tested for antibodies against HIV-1 and HHV-8 in 3344 of the patients. Antibodies against HHV-8 were detected with an indirect immunofluorescence assay. The intensity of the fluorescent signal correlated well with the titers of antibodies (P<0.001). The relations among the presence of anti–HHV-8 antibodies, sociodemographic and behavioral factors, type of cancer, and the presence or absence of coexistent HIV-1 infection were examined with the use of unconditional logistic-regression models.

Results

Among the 3293 subjects with cancers other than Kaposi's sarcoma, the standardized seroprevalence of antibodies against HHV-8 was 32 percent, which did not differ significantly from the standardized seroprevalence among black blood donors. Among these 3293 patients, the prevalence of antibodies against HHV-8 increased with increasing age (P<0.001) and an increasing number of sexual partners (P=0.05) and decreased with increasing years of education (P=0.007); it was not strongly associated with HIV-1 infection. Anti–HHV-8 antibodies were more frequent among black than white blood donors (P<0.001). Among the 51 patients with Kaposi's sarcoma, the standardized seroprevalence of antibodies against HHV-8 was 83 percent, significantly higher than the prevalence among those without Kaposi's sarcoma (P<0.001). For 16 other specific types of cancer, including multiple myeloma (108 cases) and prostate cancer (202 cases), the variation in the standardized seroprevalence of antibodies against HHV-8 was not remarkable. At a given intensity of fluorescence of anti–HHV-8 antibodies, Kaposi's sarcoma was more frequent among HIV-1–positive patients than among those who were HIV-1–negative (P<0.001).

Conclusions

Among black patients with cancer in South Africa, the seroprevalence of anti–HHV-8 antibodies is high and is specifically associated with Kaposi's sarcoma, particularly at high titers.

Media in This Article

Figure 2Age-Specific Seroprevalence of Antibodies against Human Herpesvirus 8 (HHV-8) and Human Immunodeficiency Virus Type 1 (HIV-1) in the Patients without Kaposi's Sarcoma.
Figure 5Distribution of Titers of Anti–Human Herpesvirus 8 (HHV-8) Antibodies in 47 Patients with Kaposi's Sarcoma and 94 Matched Controls.
Article

Human herpesvirus 8 (HHV-8, also known as Kaposi's sarcoma–associated herpesvirus) has been consistently linked to Kaposi's sarcoma.1-3 HHV-8 is detectable in the lesions of nearly all patients with Kaposi's sarcoma,4,5 and its presence in the blood predicts the development of Kaposi's sarcoma.6,7 This neoplasm occurs frequently in patients with the acquired immunodeficiency syndrome (AIDS),8 but it was common in central Africa even before the advent of AIDS.9 With the AIDS epidemic now spreading through central and southern Africa, Kaposi's sarcoma has become the most commonly diagnosed cancer in some countries in those regions.10,11 The incidence of Kaposi's sarcoma is increasing rapidly in South Africa.12 In the United States and most of Europe Kaposi's sarcoma, which was rare before the advent of AIDS, now occurs mainly among homosexual men with AIDS.8

Little is known about the transmission of HHV-8, its association with other cancers, or its interaction with the human immunodeficiency virus type 1 (HIV-1). The few studies investigating the spread of HHV-8 infection have tended to be small, but they suggest that the routes include sexual transmission among homosexual men in the United States13 and mother-to-child transmission in South Africa.14

HHV-8 has also been found in association with primary-effusion lymphoma in patients with AIDS,15-17 and some investigators have suggested, largely on the basis of molecular studies, that multiple myeloma18 and prostate cancer5 are also associated with HHV-8 infection. These reports, however, have not been confirmed.19-22 We studied the relations among the presence of antibodies against HHV-8, the risk of cancer, and other factors, including the presence or absence of HIV-1 infection, in over 3000 black patients from Johannesburg and Soweto, South Africa, in whom cancer was diagnosed between 1992 and 1997.

Methods

Study Population

Data from two large epidemiologic studies conducted by researchers from the South African National Cancer Registry and the Department of Medicine of the University of the Witwatersrand, in collaboration with investigators in the United Kingdom, are included in this report. In the first study, performed between January 1992 and December 1994, information was collected on the age, sex, and birthplace of 1015 black inpatients with cancer at the Chris Hani–Baragwanath, Hillbrow, and Johannesburg hospitals, which are the main teaching hospitals in Johannesburg and Soweto.12 In the second study, performed between January 1994 and October 1997, trained nurses interviewed 2576 black inpatients with cancer at the same three hospitals using a standard questionnaire in the language of the patient (usually Zulu or Sotho). Questions were asked about sociodemographic and behavioral characteristics, including age, sex, birthplace, residence, years of education, and reproductive and lifetime sexual history. Diagnoses of cancer were established, where appropriate, by biopsy, examination of blood or bone marrow, or cytologic techniques, or by a combination of these methods. Both studies were approved by the ethics committee of the University of the Witwatersrand, and informed consent was obtained. For comparative purposes, serum samples were obtained consecutively from 85 black and 224 white blood donors at the Johannesburg blood-transfusion service (unpublished data). Samples were collected in each study and stored at –30°C.

Serologic Tests for HHV-8 and HIV-1

The serum samples were shipped by air on dry ice to the Institute of Cancer Research in London for HHV-8 testing. All assays were performed by a single observer who was unaware of each patient's personal characteristics and diagnosis. A body-cavity–related B-cell lymphoma (primary effusion lymphoma) cell line, BCP-1, which is positive for HHV-8 and negative for the Epstein–Barr virus (EBV), was used for an indirect immunofluorescence assay to detect IgG antibodies against HHV-8 antigen.23,24 Latently infected BCP-1 cells were fixed in 4 percent paraformaldehyde and were made permeable with 0.2 percent Triton X-100. Cells were resuspended in phosphate-buffered saline and fixed on glass slides. The samples were diluted 1:100 in phosphate-buffered saline with 3 percent fetal-calf serum. The diluted serum was added to the fixed BCP-1 cells and incubated at 22°C for 45 minutes.

After the slides were washed in phosphate-buffered saline with 3 percent fetal-calf serum, rabbit antihuman IgG labeled with fluorescein isothiocyanate (Dako, High Wycombe, United Kingdom), diluted 1:40 in phosphate-buffered saline with 3 percent fetal-calf serum, was added, and the slides were incubated at 22°C for 20 minutes. The slides were then washed in phosphate-buffered saline without fetal-calf serum and screened by ultraviolet microscopy for the nuclear stippling pattern characteristic of antibodies against the latent nuclear antigen of HHV-8 encoded by orf73.23,25-29 The HHV-8–negative cell lines Raji and Daudi were used as controls.

Serum samples that were positive for antibodies against HHV-8 by the immunofluorescence assay were then scored as low, medium, or high according to the intensity of the fluorescent signal. These scores correlated well with the intensity of fluorescence as measured by fluorescence-activated cell-sorter (FACS) analysis. Figure 1AFigure 1Fluorescent-Signal Intensity and Distribution of Titers of Antibodies against Human Herpesvirus 8 (HHV-8). shows the results of FACS analysis for six subjects, two of whose samples had been scored as low, two as medium, and two as high in terms of the fluorescent-signal intensity. The reproducibility of these results was examined whenever there was sufficient serum for retesting from the patients with Kaposi's sarcoma (47 patients) and from 94 matched controls without Kaposi's sarcoma (for each retested sample from a patient with Kaposi's sarcoma, we selected serum samples from 2 control subjects without Kaposi's sarcoma who had the same HIV-1 status and whose age was as close as possible to that of the patient).

The serum samples from these 141 subjects were retested in a blinded fashion with the immunofluorescence assay, and the intensity of the fluorescent signal was scored again (absent, low, medium, or high). The results of the repeated test were in complete agreement with those of the first test for the patients with Kaposi's sarcoma (40 were positive according to the immunofluorescence assay, and 7 were negative), and in 94 percent agreement for those who did not have Kaposi's sarcoma (about one third were positive according to the immunofluorescence assay). The scores for signal intensity also agreed well: exact agreement was obtained for 85 percent of those with Kaposi's sarcoma and for 90 percent of those without Kaposi's sarcoma.

To study the relation between the intensity of fluorescence and the titer of antibodies to HHV-8, the 141 serum samples selected for retesting were also examined in a blinded fashion at doubling dilutions, starting at 1:100 for antibodies against HHV-8.30 The score for the fluorescent-signal intensity was strongly related to antibody titer — the median titers were 1:200 for low signal intensity, 1:51,200 for medium signal intensity, and 1:204,800 for high signal intensity (P<0.001) (Figure 1B).

Testing for HIV-1 was conducted at the Serology Department of the South African Institute for Medical Research in Johannesburg. After presumptive positive results by enzyme-linked immunosorbent assay, the presence of HIV-1 infection was confirmed in the first study either by Western blot analysis or by three third-generation tests.12 In the second study, one test was performed for each patient and those with an equivocal result were considered to be HIV-1–negative.

Statistical Analysis

We recruited 3591 patients between 1992 and 1997. Serum samples from 3344 of them (93 percent) were tested for antibodies to HHV-8, and these results are the basis for the analyses presented in this report. Since the factors influencing HHV-8 infection in the general population are not known, we initially examined the relation between antibodies against HHV-8 and age, sex, education, place of birth, parity, and number of lifetime sexual partners in the patients without Kaposi's sarcoma. Odds ratios were calculated by unconditional logistic regression and, because information on factors other than age and sex were not collected in the first study, analyses with respect to the other four factors were performed for the second study only. The results were examined at two levels of fluorescence intensity by immunofluorescence assay (i.e., according to whether there was any positive result, which corresponded to an antibody titer of at least 1:100, and according to whether there were positive results at a high signal intensity, which corresponded to a median antibody titer of 1:204,800).

To examine the relation between antibodies against HHV-8 and type of cancer, an unconditional logistic-regression model was used to calculate the log of the odds of HHV-8 seropositivity for each type of cancer for which there were 50 or more patients and for the blood donors, with adjustment for age (<35, 35 to 44, 45 to 54, 55 to 64, or ≥65 years), sex, years of education (unknown, none, one to five, or six or more), and number of sexual partners (unknown, zero to two, three or four, or five or more). Since adjustment for years of education and number of sexual partners had no material effect on the outcome of the analyses according to cancer type, the results for both studies were combined, with the patients from the first study assigned to the unknown categories for years of education and number of sexual partners. To present these results in a directly interpretable form, estimates of the adjusted log (odds) of infection for each type of cancer were transformed into estimates of standardized rates of prevalence with corresponding 95 percent confidence intervals. The resulting estimates represent prevalence rates for each cancer type standardized to a population containing men and women in equal proportion between the ages of 35 and 44 years, with one to five years of education and three or four sexual partners.

To study the relation between Kaposi's sarcoma and fluorescent-signal intensity for anti–HHV-8 antibodies separately in HIV-1–positive and HIV-1–negative patients, floating absolute risks and their corresponding floated confidence intervals were calculated,31 with the patients with other cancers as the comparison group. Presentation of the results in this way permitted us to make valid comparisons between any two groups, regardless of signal intensity or HIV-1 status, after taking into account the variation in each floating absolute risk. These risks were calculated with the use of unconditional logistic-regression models, with adjustment for age, sex, and, if known, years of education and number of sexual partners.

Results

Antibodies against HHV-8 in Relation to Demographic and Behavioral Factors

The serum samples of 1196 of the 3293 patients who did not have Kaposi's sarcoma were positive for antibodies against HHV-8 according to the immunofluorescence assay. Of the 1196 positive samples, 58 percent (698 of 1196) had a low fluorescent-signal intensity, 30 percent (359 of 1196) had a medium intensity, and 12 percent (139 of 1196) had a high intensity. The seroprevalence of antibodies against HHV-8 increased steadily with age — from 24 percent for those 15 to 24 years of age to 49 percent for those 65 or more years of age (P<0.001 by test for trend) (Figure 2Figure 2Age-Specific Seroprevalence of Antibodies against Human Herpesvirus 8 (HHV-8) and Human Immunodeficiency Virus Type 1 (HIV-1) in the Patients without Kaposi's Sarcoma.). The corresponding age-specific seroprevalence rates for patients with a high signal intensity were 1.0 percent and 7.9 percent, respectively (P for trend, <0.001).

Table 1Table 1Odds Ratios for Human Herpesvirus 8 Seropositivity According to Characteristics of Patients without Kaposi's Sarcoma. shows the age- and sex-adjusted odds ratios for the presence of antibodies against HHV-8 according to sex, years of education, place of birth (urban or rural area), parity, and number of lifetime sexual partners. The presence of these antibodies was not significantly related to sex, place of birth, or parity. However, the prevalence of seropositivity decreased with increasing years of education (P for trend=0.007) and increased with the number of sexual partners (P for trend=0.05). Broadly similar relations were seen when the analyses were restricted to the patients who were seronegative for HIV-1 (Table 1). Adjustment for years of education and number of sexual partners with respect to the other factors shown in Table 1 did not alter the results materially.

Antibodies against HHV-8 in Relation to Cancer

The presence of antibodies against HHV-8 among patients with any of 17 types of cancer and among the black blood donors is shown in Figure 3Figure 3Standardized Prevalence of Antibodies against Human Herpesvirus 8 (HHV-8) at Two Levels of Fluorescent-Signal Intensity among 3344 Black South African Patients with Cancer and 85 Black Blood Donors. at two levels of fluorescent-signal intensity. Prevalence rates were standardized according to age, sex, years of education, and number of sexual partners. At each level of intensity, the standardized prevalence of antibodies against HHV-8 among the patients with Kaposi's sarcoma differed significantly from the rates found for other cancers (for any positive signal, P<0.001; for a high-intensity signal, P<0.001). The seroprevalence rates among those with the other 16 types of cancer were similar, and there was little evidence of variation in the rates according to type of cancer (for any positive signal, P=0.05; for a high-intensity signal, P=0.3).

The standardized prevalence of antibodies against HHV-8 among the 51 patients with Kaposi's sarcoma was 83 percent (95 percent confidence interval, 70 to 91 percent) on the basis of the presence of any positive signal and 45 percent (95 percent confidence interval, 26 to 66 percent) on the basis of the presence of a high-intensity signal. The corresponding figures for the patients with all other cancers combined were 32 percent (95 percent confidence interval, 28 to 38 percent) and 2.0 percent (95 percent confidence interval, 1.1 to 3.6 percent), respectively, which do not differ significantly from the values for the black blood donors (20 percent [95 percent confidence interval, 10 to 35 percent] and 3 percent [95 percent confidence interval, 0.4 to 20 percent]). For the patients with multiple myeloma, the corresponding figures were 24 percent (95 percent confidence interval, 16 to 33 percent) and 1.5 percent (95 percent confidence interval, 0.5 to 5 percent), and for those with prostate cancer the figures were 33 percent (95 percent confidence interval, 25 to 43 percent) and 2.4 percent (95 percent confidence interval, 1 to 5 percent). None of the rates among the patients with myeloma or prostate cancer differed significantly from those among the patients with cancer other than Kaposi's sarcoma, nor were there any significant trends with increasing signal intensity for the patients with any of the other cancers.

Antibodies against HIV-1 in Relation to Antibodies against HHV-8 and the Presence of Kaposi's Sarcoma

The standardized seroprevalence of anti–HIV-1 antibodies was 75 percent among the patients with Kaposi's sarcoma and 5 percent among those with other cancers. As expected, the highest prevalence rates for anti–HIV-1 antibodies were found in young adults (Figure 2), and the prevalence of such antibodies among the patients without Kaposi's sarcoma increased with the number of sexual partners. The odds ratio for the presence of HIV-1 antibodies among the patients with three or four sexual partners, as compared with those with zero to two partners, was 1.3 (95 percent confidence interval, 0.7 to 2.6), and the odds ratio among the patients with five or more sexual partners, as compared with those with zero to two partners, was 3.1 (95 percent confidence interval, 1.6 to 6.0).

There was little difference in the standardized prevalence of antibodies against HHV-8 among the patients who were seropositive for HIV-1 and those who were seronegative (30 percent vs. 33 percent). Only a weak relation was found between the fluorescent-signal intensity for anti–HHV-8 antibodies and HIV-1 infection, with the patients who were seropositive for HIV-1 about twice as likely as the seronegative patients to have medium-intensity signals (odds ratio, 2.0; 95 percent confidence interval, 1.3 to 3.2) or high-intensity signals (odds ratio, 2.0; 95 percent confidence interval, 0.9 to 4.4) for anti–HHV-8 antibodies.

Both among patients who were seronegative for HIV-1 and those who were seropositive, Kaposi's sarcoma was more frequent among those with high-intensity fluorescent signals for antibodies against HHV-8 (P<0.001 for trend with increasing signal intensity) (Figure 4Figure 4Risk of Kaposi's Sarcoma among Patients with Cancer, According to Fluorescent-Signal Intensity and HIV-1 Status.). However, at each level of HHV-8 signal intensity, Kaposi's sarcoma was more likely among the HIV-1–positive patients than among those who were HIV-1–negative (P<0.001). Since signal intensity is an indirect measure of antibody titer, we repeated the analyses using the results from the 141 patients whose titers of antibody against HHV-8 had been measured directly. Associations similar to those shown in Figure 4 were found.

Figure 5Figure 5Distribution of Titers of Anti–Human Herpesvirus 8 (HHV-8) Antibodies in 47 Patients with Kaposi's Sarcoma and 94 Matched Controls. shows the distribution of anti–HHV-8 antibody titers for 47 patients with Kaposi's sarcoma and controls matched for age and HIV-1 status. Eighty-five percent of the serum samples from these patients had anti–HHV-8 titers ≥1:100, and 68 percent had titers ≥1:51,000. The corresponding figures were 35 percent and 13 percent, respectively, for the matched controls. Figure 5 also shows that HIV-1 infection did not have an appreciable effect on the titer of anti–HHV-8 antibodies.

Discussion

We found that about one third of the serum samples from the black South African patients with cancer whom we studied had antibodies against HHV-8. In this population, the prevalence of antibodies against HHV-8 increased with increasing age and a higher number of sexual partners; it was higher among those with fewer years of education, but it was not strongly related to HIV-1 infection. The seroprevalence of HHV-8 was highest among the patients with Kaposi's sarcoma, as compared with the patients with any of the other 16 types of cancer studied, including multiple myeloma and prostate cancer. Kaposi's sarcoma was more common than other tumors among patients with high titers of antibody against HHV-8, and, at a given anti–HHV-8 titer, Kaposi's sarcoma was more frequent in HIV-1–positive patients than in those who were HIV-1–negative.

The black patients with cancers other than Kaposi's sarcoma appeared to be typical of other black populations in South Africa with respect to HHV-8 infection in that the prevalence of anti–HHV-8 antibodies among them was similar to that among the black blood donors from the same area (Figure 3). The standardized prevalence of antibodies against HHV-8 was substantially greater among black blood donors than among white blood donors from the same area (20 percent vs. 5 percent) (unpublished data). With the use of similar assays, less than 5 percent of blood donors from the United States or the United Kingdom have been shown to have antibodies against HHV-8.23,25,30

The immunofluorescence assay we used detects antibodies against the latent nuclear antigen of HHV-8 encoded by orf7327-29; it has been used to study the seroprevalence of this virus.13,14,21,23,25,26,30 Like other serologic assays, the immunofluorescence assay is not sensitive enough to identify every person infected with HHV-8, but it does detect antibodies against HHV-8 in over 80 percent of patients with Kaposi's sarcoma. Sensitive polymerase-chain-reaction methods can demonstrate the presence of HHV-8 in the tumor tissue of virtually all patients with Kaposi's sarcoma. On the other hand, the immunofluorescence assay is highly specific and reveals antibodies against particular HHV-8 antigens.27-29 An immunofluorescence assay against lytically induced HHV-8–positive cells has been reported to detect infection in a higher proportion of North American blood donors than the assay for antibodies against latent HHV-8 antigens used in our study.32 However, that assay is likely to be less specific than the one we used, because it detects antibodies against undefined HHV-8 proteins. In blinded comparative studies the immunofluorescence assay we used was shown to be the most sensitive and specific assay for HHV-8.33 From an epidemiologic perspective, the immunofluorescence assay and the fluorescent-signal-intensity scoring system we used are highly reproducible and correlate well with directly measured titers of antibody against HHV-8.

Comparatively little is known about factors associated with HHV-8 infection in Africa or, indeed, elsewhere in the world. Studies of homosexual men in Western countries suggest that the prevalence of antibodies against HHV-8 increases when sexual partners are numerous,13,26 findings parallel with our results. We have shown that among black South African patients with cancer other than Kaposi's sarcoma, there is a trend toward increasing prevalence of antibodies against HHV-8 with increasing numbers of sexual partners. Our results also suggest that, in this population, sexual transmission of HHV-8 might not be as efficient as sexual transmission of HIV-1, since the odds ratio associated with having had five or more sexual partners, as compared with zero to two partners, was only 1.3 (95 percent confidence interval, 1.0 to 1.7) for antibodies against HHV-8 but 3.1 (95 percent confidence interval, 1.5 to 6.0) for antibodies against HIV-1.

Furthermore, transmission from mother to child appears to be common in Johannesburg, with about one third of the mothers infected with HHV-8 transmitting the virus to their children.14 Therefore, sexual transmission is clearly not the only mode of spreading HHV-8 in South Africa, and there may be other, as yet unknown, routes. The fact that HHV-8 seroprevalence increases with age suggests that the virus may have been prevalent in this population for some time — a recently introduced virus that is transmitted in adults mainly by a sexual route would be found predominantly among young adults, as is the case for HIV-1 in this population (Figure 2) and throughout Africa. The lower prevalence of anti–HHV-8 antibodies among whites than among blacks and the observation that among blacks the prevalence declines with increasing education suggest that factors associated with poverty may contribute to the transmission of the virus.

Kaposi's sarcoma was the only cancer among the 17 types we studied that was associated with a high seroprevalence of antibodies against HHV-8. These results indicate that HHV-8 has little, if any, specific association with the other cancers we studied, including multiple myeloma and prostate cancer. Although some molecular studies have suggested an association between HHV-8 and multiple myeloma or prostate cancer,5,18 various other serologic and molecular studies have not been able to confirm these associations.19-21

Kaposi's sarcoma was especially frequent among those with high signal intensities in the fluorescent test and high titers of antibody against HHV-8 (Figure 4 and Figure 5). This association is similar to the relation between EBV in African Burkitt's lymphoma34 and nasopharyngeal cancer,35 in which high antibody titers correlate with the risk of disease. Our results were measured in serum samples collected at the time that Kaposi's sarcoma was diagnosed, and no data are available on how signal intensity or antibody titer vary over time in the same patient before diagnosis. It seems unlikely that these associations are a consequence of the disease, since the detection of HHV-8 by the polymerase chain reaction in peripheral-blood mononuclear cells, which is also an indicator of a high viral load, has been shown to predict the subsequent development of Kaposi's sarcoma in HIV-1–positive patients.6,7 In Italy, a study of titers of antibodies against HHV-8 in blood donors found the highest titers among populations at highest risk for HIV-1–negative, or classic, Kaposi's sarcoma.30

HIV-1 infection does not appear to have a substantial effect on the presence or titer of anti–HHV-8 antibodies (Figure 5) — further evidence that the association between the titer of anti–HHV-8 antibodies and Kaposi's sarcoma is not a consequence of the disease. Instead, it appears that infection with HIV-1 has a separate effect with respect to Kaposi's sarcoma, which is independent of the anti–HHV-8 antibody titer (Figure 4). The HHV-8 viral load may differ between persons infected with HIV-1 and those who are uninfected who have similar antibody titers, but relevant data are not yet available. Alternatively, HIV-1 infection may affect the development of Kaposi's sarcoma in a way that is unrelated to the HHV-8 viral load, perhaps through HIV-1–related immune dysregulation or its transactivation (Tat) protein.36 Currently, however, there is no obvious explanation for our finding of striking differences in the likelihood of HHV-8–associated Kaposi's sarcoma between HIV-1–positive patients and those who were HIV-1–negative.

Supported by the South African Institute for Medical Research, the South African Medical Research Council, the Cancer Association of South Africa, the South African Department of Health, the Imperial Cancer Research Fund, the Cancer Research Campaign, and the Medical Research Council (United Kingdom).

We are indebted to Sister F. Motsepe, Sister H. Mphaloane, Sister E. Morease, and Sister S. Ngcukana for performing all the interviews; to Sister M. Kubekha, manager of the phlebotomy service; to Ms. F. Mngomezulu, Ms. J. Knuppel, Ms. S. Letsoalo, Ms. V. Davis, Ms. M. Terblanche, and Mr. J. Madhoo for data coding and entry and for specimen preparation; to Mrs. P. Caenazzo and Ms. S. Zaba for HIV-1 testing; to Mrs. N. Langston for typing the manuscript; to Dr. Paul Appleby for preparing the figures; to all the clinicians (especially Dr. B. Fine of the dermatology clinic) and matrons in charge of Chris Hani–Baragwanath, Hillbrow, and Johannesburg hospitals for granting access to the clinics and wards; and to the patients for their participation in this study.

Source Information

From the South African Cancer Epidemiology Unit, National Cancer Registry (F.S., H.C., R.P.-N.), and the Departments of Anatomical Pathology (F.S., H.C., R.P.-N.) and Serology (U.J.), South African Institute for Medical Research — both in Johannesburg; the Imperial Cancer Research Fund Cancer Epidemiology Unit, University of Oxford, Oxford, United Kingdom (V.B., R.N., G.R., D. Bull); and the Departments of Oncology and Molecular Pathology, University College London, London (D. Bourboulia, D.W., C.B., R.W.).

Address reprint requests to Dr. Sitas at the South African Institute for Medical Research, P.O. Box 1038, Johannesburg 2000, South Africa, or at .

Other authors were Moosa Patel, F.C.P.(S.A.), M.Med., Paul Ruff, M.B., B.Ch., M.Med., Werner R. Bezwoda, F.C.P., Ph.D., and Edna Retter, L.M.C. (University of the Witwatersrand, Johannesburg, South Africa); and Martin Hale, M.B., Ch.B., F.C.Path. (South African Institute for Medical Research, Johannesburg).

References

References

  1. 1

    Chang Y, Cesarman E, Pessin MS, et al. Identification of herpesvirus-like DNA sequences in AIDS-associated Kaposi's sarcoma. Science 1994;266:1865-1869
    CrossRef | Web of Science | Medline

  2. 2

    Moore PS, Chang Y. Kaposi's sarcoma (KS), KS-associated herpesvirus, and the criteria for causality in the age of molecular biology. Am J Epidemiol 1998;147:217-221
    Web of Science | Medline

  3. 3

    Boshoff C, Weiss RA. Kaposi's sarcoma-associated herpesvirus. In: von de Woude G, Klein G, eds. Advances in cancer research. Vol. 75. San Diego, Calif.: Academic Press, 1998:56-86.

  4. 4

    Boshoff C, Schultz TF, Kennedy MM, et al. Kaposi's sarcoma-associated herpesvirus infects endothelial and spindle cells. Nat Med 1995;1:1274-1278
    CrossRef | Web of Science | Medline

  5. 5

    Staskus KA, Zhong W, Gebhard K, et al. Kaposi's sarcoma-associated herpesvirus gene expression in endothelial (spindle) tumor cells. J Virol 1997;71:715-719
    Web of Science | Medline

  6. 6

    Whitby D, Howard MR, Tenant-Flowers M, et al. Detection of Kaposi's sarcoma associated herpesvirus in peripheral blood of HIV-infected individuals and progression to Kaposi's sarcoma. Lancet 1995;346:799-802
    CrossRef | Web of Science | Medline

  7. 7

    Moore PS, Kingsley LA, Holmberg SD, et al. Kaposi's sarcoma-associated herpesvirus infection prior to onset of Kaposi's sarcoma. AIDS 1996;10:175-180
    CrossRef | Web of Science | Medline

  8. 8

    Beral V, Peterman TA, Berkelman RL, Jaffe HW. Kaposi's sarcoma among persons with AIDS: a sexually transmitted infection? Lancet 1990;335:123-128
    CrossRef | Web of Science | Medline

  9. 9

    Cook-Mozaffari P, Newton R, Beral V, Burkitt DP. The geographical distribution of Kaposi's sarcoma and of lymphomas in Africa before the AIDS epidemic. Br J Cancer 1998;78:1521-1528
    CrossRef | Web of Science | Medline

  10. 10

    Wabinga HR, Parkin DM, Wabwire-Mangen F, Mugerwa JW. Cancer in Kampala, Uganda, in 1989-91: changes in incidence in the era of AIDS. Int J Cancer 1993;54:23-36
    CrossRef | Web of Science

  11. 11

    Bassett MT, Chokunoga E, Mauchaza B, Levy L, Ferlay J, Parkin DM. Cancer in the African population of Harare, Zimbabwe, 1990-1992. Int J Cancer 1995;63:29-36[Erratum, Int J Cancer 1995;63:76.]
    CrossRef | Web of Science | Medline

  12. 12

    Sitas F, Bezwoda WR, Levin V, et al. Association between human immunodeficiency virus type 1 infection and cancer in the black population of Johannesburg and Soweto, South Africa. Br J Cancer 1997;75:1704-1707
    CrossRef | Web of Science | Medline

  13. 13

    Martin JN, Ganem DE, Osmond DH, Page-Shafer KA, Macrae D, Kedes DH. Sexual transmission and the natural history of human herpesvirus 8 infection. N Engl J Med 1998;338:948-954
    Full Text | Web of Science | Medline

  14. 14

    Bourboulia D, Whitby D, Boshoff C, et al. Serologic evidence for mother-to-child transmission of Kaposi sarcoma-associated herpesvirus infection. JAMA 1998;280:31-32
    CrossRef | Web of Science | Medline

  15. 15

    Cesarman E, Chang Y, Moore PS, Said JW, Knowles DM. Kaposi's sarcoma-associated herpesvirus-like DNA sequences in AIDS-related body-cavity-based lymphomas. N Engl J Med 1995;332:1186-1191
    Full Text | Web of Science | Medline

  16. 16

    Ansari MQ, Dawson DB, Nador R, et al. Primary body cavity-based AIDS-related lymphomas. Am J Clin Pathol 1996;105:221-229
    Web of Science | Medline

  17. 17

    Gaidano G, Pastore C, Gloghini A, et al. Distribution of human herpesvirus-8 sequences throughout the spectrum of AIDS-related neoplasia. AIDS 1996;10:941-949
    CrossRef | Web of Science | Medline

  18. 18

    Rettig MB, Ma HJ, Vescio RA, et al. Kaposi's sarcoma-associated herpesvirus infection of bone marrow dendritic cells from multiple myeloma patients. Science 1997;276:1851-1854
    CrossRef | Web of Science | Medline

  19. 19

    Parravicini C, Lauri E, Baldini L, et al. Kaposi's sarcoma-associated herpesvirus infection and multiple myeloma. Science 1997;278:1969-1970
    CrossRef | Web of Science | Medline

  20. 20

    Masood R, Zheng T, Tupule A, et al. Kaposi's sarcoma-associated herpesvirus infection and multiple myeloma. Science 1997;278:1970-1971
    Web of Science | Medline

  21. 21

    Whitby D, Boshoff C, Luppi M, Torelli G. Kaposi's sarcoma-associated herpesvirus infection and multiple myeloma. Science 1997;278:1971-1972
    Web of Science | Medline

  22. 22

    Munker R, Tasaka T, Park D, Miller CW, Koeffler HP. HHV-8 (KSHV) does not establish latency in prostate cancer cell lines. Prostate 1997;33:286-288
    CrossRef | Web of Science | Medline

  23. 23

    Gao SJ, Kingsley L, Li M, et al. KSHV antibodies among Americans, Italians and Ugandans with and without Kaposi's sarcoma. Nat Med 1996;2:925-928
    CrossRef | Web of Science | Medline

  24. 24

    Boshoff C, Gao SJ, Healy LE, et al. Establishing a KSHV+ cell line (BCP-1) from peripheral blood and characterizing its growth in Nod/SCID mice. Blood 1998;91:1671-1679
    Web of Science | Medline

  25. 25

    Simpson GR, Schulz TF, Whitby D, et al. Prevalence of Kaposi's sarcoma associated herpesvirus infection measured by antibodies to recombinant capsid protein and latent immunofluorescence antigen. Lancet 1996;348:1133-1138
    CrossRef | Web of Science | Medline

  26. 26

    Kedes DH, Operskalski E, Busch M, Kohn R, Flood J, Ganem D. The seroepidemiology of human herpesvirus 8 (Kaposi's sarcoma-associated herpesvirus): distribution of infection in KS risk groups and evidence for sexual transmission. Nat Med 1996;2:918-924[Erratum, Nat Med 1996;2:1041.]
    CrossRef | Web of Science | Medline

  27. 27

    Rainbow L, Platt GM, Simpson GR, et al. The 222- to 234-kilodalton latent nuclear protein (LNA) of Kaposi's sarcoma-associated herpesvirus (human herpesvirus 8) is encoded by orf73 and is a component of the latency-associated nuclear antigen. J Virol 1997;71:5915-5921
    Web of Science | Medline

  28. 28

    Kellam P, Boshoff C, Whitby D, Matthews S, Weiss RA, Talbot SJ. Identification of a major latent nuclear antigen, LNA-1, in the human herpesvirus 8 genome. J Hum Virol 1997;1:19-29
    Medline

  29. 29

    Kedes DH, Lagunoff M, Renne R, Ganem D. Identification of the gene encoding the major latency-associated nuclear antigen of the Kaposi's sarcoma-associated herpesvirus. J Clin Invest 1997;100:2606-2610
    CrossRef | Web of Science | Medline

  30. 30

    Whitby D, Luppi M, Barozzi P, Boshoff C, Weiss RA, Torelli G. Human herpesvirus 8 seroprevalence in blood donors and lymphoma patients from different regions of Italy. J Natl Cancer Inst 1998;90:395-397
    CrossRef | Web of Science | Medline

  31. 31

    Easton DF, Peto J, Babiker AGAG. Floating absolute risk: an alternative to relative risk in survival and case-control analysis avoiding an arbitrary reference group. Stat Med 1991;10:1025-1035
    CrossRef | Web of Science | Medline

  32. 32

    Lennette ET, Blackbourn DJ, Levy JA. Antibodies to human herpesvirus type 8 in the general population and in Kaposi's sarcoma patients. Lancet 1996;348:858-861
    CrossRef | Web of Science | Medline

  33. 33

    Rabkin CS, Schulz TF, Whitby D, et al. Interassay correlation of human herpesvirus serologic tests. J Infect Dis 1998;178:304-309
    Web of Science | Medline

  34. 34

    de-The G, Geser A, Day NE, et al. Epidemiological evidence for causal relationship between Epstein-Barr virus and Burkitt's lymphoma from Ugandan prospective study. Nature 1978;274:756-761
    CrossRef | Web of Science | Medline

  35. 35

    de-Thé G, Lavoue MF, Muenz L. Differences in EBV antibody titres of patients with nasopharyngeal carcinoma originating from high, intermediate and low incidence areas. In: de-Thé, Ito Y, eds. Nasopharyngeal carcinoma: etiology and control. Lyons, France: International Agency for Research on Cancer, 1978. (IARC scientific publications no. 20.)

  36. 36

    Ensoli B, Barillari G, Salahuddin SZ, Gallo RC, Wong-Staal F. Tat protein of HIV-1 stimulates growth of cells derived from Kaposi's sarcoma lesions of AIDS patients. Nature 1990;345:84-86
    CrossRef | Web of Science | Medline

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  1. 1

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    CrossRef

  2. 2

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    CrossRef

  3. 3

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    CrossRef

  4. 4

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    CrossRef

  5. 5

    Hui Wang, Jian Liu, Dilimulati A, Liang Li, Zhihui Ren, Hao Wen, Xing Wang. (2011) Seroprevalence and risk factors of Kaposi's sarcoma-associated herpesvirus infection among the general Uygur population from south and north region of Xinjiang, China. Virology Journal 8:1, 539
    CrossRef

  6. 6

    Ruth M. Pfeiffer, William A. Wheeler, Georgina Mbisa, Denise Whitby, James J. Goedert, Guy de Thé, Sam M. Mbulaiteye. (2010) Geographic Heterogeneity of Prevalence of the Human Herpesvirus 8 in Sub-Saharan Africa: Clues About Etiology. Annals of Epidemiology 20:12, 958-963
    CrossRef

  7. 7

    Nontuthuzelo IM Somdyala, Debbie Bradshaw, Wentzel CA Gelderblom, Donald M Parkin. (2010) Cancer incidence in a rural population of South Africa, 1998-2002. International Journal of Cancer 127:10, 2420-2429
    CrossRef

  8. 8

    S. Meschi, M. Sañé Schepisi, E. Nicastri, N. Bevilacqua, C. Castilletti, M.R. Sciarrone, M.G. Paglia, R. Fumakule, J. Mohamed, A. Kitwa, S. Mangi, F. Molteni, A. Di Caro, F. Vairo, M.R. Capobianchi, G. Ippolito. (2010) The prevalence of antibodies to human herpesvirus 8 and hepatitis B virus in patients in two hospitals in Tanzania. Journal of Medical Virology 82:9, 1569-1575
    CrossRef

  9. 9

    Sheena G Sullivan, Hans H Hirsch, Silvia Franceschi, Ingrid Steffen, Emmanuelle Boffi El Amari, Nicolas J Mueller, Ioannis Magkouras, Robert J Biggar, Martin Rickenbach, Gary M Clifford. (2010) Kaposi sarcoma herpes virus antibody response and viremia following highly active antiretroviral therapy in the Swiss HIV Cohort study. AIDS 24:14, 2245-2252
    CrossRef

  10. 10

    Siobhan Sutcliffe. (2010) Sexually transmitted infections and risk of prostate cancer: review of historical and emerging hypotheses. Future Oncology 6:8, 1289-1311
    CrossRef

  11. 11

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    CrossRef

  12. 12

    Velia Ramírez-Amador, Gabriela Anaya-Saavedra, Guillermo Martínez-Mata. (2010) Kaposi’s sarcoma of the head and neck: A review. Oral Oncology 46:3, 135-145
    CrossRef

  13. 13

    Eleftherios C. Vamvakas. (2010) Is Human Herpesvirus-8 Transmitted by Transfusion?. Transfusion Medicine Reviews 24:1, 1-14
    CrossRef

  14. 14

    Thomas F. Schulz. (2009) Cancer and viral infections in immunocompromised individuals. International Journal of Cancer 125:8, 1755-1763
    CrossRef

  15. 15

    Bishi Fu, Feng Sun, Baolin Li, Lei Yang, Yan Zeng, Xiulian Sun, Fanhong Xu, Simon Rayner, Moraima Guadalupe, Shou-Jiang Gao, Linding Wang. (2009) Seroprevalence of Kaposi's sarcoma-associated herpesvirus and risk factors in Xinjiang, China. Journal of Medical Virology 81:8, 1422-1431
    CrossRef

  16. 16

    Mariana Cavalheiro Magri, Paulo Henrique Lage Carbone, Elizabeth de los Santos-Fortuna, Adele Caterino-de-Araujo. (2009) A comparative study of the frequency of antibody and titers against human herpesvirus 8 latent and lytic antigens in “at-risk” individuals and among patients with Kaposi's sarcoma. Journal of Medical Virology 81:7, 1292-1297
    CrossRef

  17. 17

    Véronique Bouvard, Robert Baan, Kurt Straif, Yann Grosse, Béatrice Secretan, Fatiha El Ghissassi, Lamia Benbrahim-Tallaa, Neela Guha, Crystal Freeman, Laurent Galichet, Vincent Cogliano. (2009) A review of human carcinogens—Part B: biological agents. The Lancet Oncology 10:4, 321-322
    CrossRef

  18. 18

    Di Qin, Chun Lu. (2008) The biology of Kaposi’s sarcoma-associated herpesvirus and the infection of human immunodeficiency virus. Virologica Sinica 23:6, 473-485
    CrossRef

  19. 19

    Maria Claudia Nascimento, Vanda Akico de Souza, Laura Masami Sumita, Wilton Freire, Helen A. Weiss, Ester C. Sabino, Silvia Franceschi, Claudio Sergio Pannuti, Philippe Mayaud. (2008) Prevalence of, and risk factors for Kaposi's sarcoma-associated herpesvirus infection among blood donors in Brazil: A multi-center serosurvey. Journal of Medical Virology 80:7, 1202-1210
    CrossRef

  20. 20

    L Stein, M I Urban, M Weber, P Ruff, M Hale, B Donde, M Patel, F Sitas. (2008) Effects of tobacco smoking on cancer and cardiovascular disease in urban black South Africans. British Journal of Cancer 98:9, 1586-1592
    CrossRef

  21. 21

    Babatyi I Malope, Patrick MacPhail, Georgina Mbisa, Catherine MacPhail, Lara Stein, Edith M Ratshikhopha, Lewis Ndhlovu, Freddy Sitas, Denise Whitby. (2008) No evidence of sexual transmission of Kaposiʼs sarcoma herpes virus in a heterosexual South African population. AIDS 22:4, 519-526
    CrossRef

  22. 22

    Sam M Mbulaiteye, James J Goedert. (2008) Transmission of Kaposi sarcoma-associated herpesvirus in sub-Saharan Africa. AIDS 22:4, 535-537
    CrossRef

  23. 23

    Marluísa de Oliveira Guimarães Ishak, Rosimar Neris Martins, Paula Renata Lima Machado, Lia Lobato Batista de Souza, Luiz Fernando Almeida Machado, Vânia Nakauth Azevedo, Harutaka Katano, Tetsutaro Sata, Hideki Hasegawa, Antonio Carlos Rosário Vallinoto, Ricardo Ishak. (2007) High diversity of HHV-8 molecular subtypes in the Amazon region of Brazil: Evidence of an ancient human infection. Journal of Medical Virology 79:10, 1537-1544
    CrossRef

  24. 24

    Assimina Zavitsanou, Vana Sypsa, Maria Petrodaskalaki, Victoria Kalapothaki, Denise Whitby, Angelos Hatzakis. (2007) Human herpesvirus 8 (HHV-8) infection in healthy urban employees from Greece: Seroprevalence and associated factors. Journal of Medical Virology 79:5, 591-596
    CrossRef

  25. 25

    Siobhan Sutcliffe, Elizabeth A. Platz. (2007) Inflammation in the etiology of prostate cancer: An epidemiologic perspective. Urologic Oncology: Seminars and Original Investigations 25:3, 242-249
    CrossRef

  26. 26

    Babatyi I Malope, Ruth M Pfeiffer, Georgina Mbisa, Lara Stein, Edith M Ratshikhopha, Dianne L O??Connell, Freddy Sitas, Patrick MacPhail, Denise Whitby. (2007) Transmission of Kaposi Sarcoma-Associated Herpesvirus Between Mothers and Children in a South African Population. JAIDS Journal of Acquired Immune Deficiency Syndromes 44:3, 351-355
    CrossRef

  27. 27

    Eric A. Engels, Sam M. Mbulaiteye, Emmanuel Othieno, Mario Gomez, Susan Mathew, Ethel Cesarman, Daniel M. Knowles, Amy Chadburn. (2007) Kaposi sarcoma-associated herpesvirus in non-Hodgkin lymphoma and reactive lymphadenopathy in Uganda. Human Pathology 38:2, 308-314
    CrossRef

  28. 28

    Denise Whitby, Vickie A. Marshall, Rachel K. Bagni, Wendell J. Miley, Thomas G. McCloud, Rebecca Hines-Boykin, James J. Goedert, Betty A.Conde, Kunio Nagashima, Judy Mikovits, Dirk P. Dittmer, David J. Newman. (2007) Reactivation of Kaposi's sarcoma-associated herpesvirus by natural products from Kaposi's sarcoma endemic regions. International Journal of Cancer 120:2, 321-328
    CrossRef

  29. 29

    Sam M. Mbulaiteye, Eric A. Engels. (2006) Kaposi's sarcoma risk among transplant recipients in the United States (1993–2003). International Journal of Cancer 119:11, 2685-2691
    CrossRef

  30. 30

    Janet M. Wojcicki, Chipepo Kankasa, Charles Mitchell, Charles Wood. (2006) Traditional practices and exposure to bodily fluids in Lusaka, Zambia. Tropical Medicine and International Health 0:0, 061030012640007-???
    CrossRef

  31. 31

    R Newton, P Coursaget, I S D Roberts. (2006) Reply: Antibody levels against BK virus and prostate, kidney and bladder cancers in the EPIC-Oxford cohort. British Journal of Cancer 94:12, 1949-1950
    CrossRef

  32. 32

    R Newton, L Carpenter, D Casabonne, V Beral, A Babiker, J Darbyshire, I Weller, R Weiss, A Kwan, D Bourboulia, F Munoz, D Lagos, C Boshoff. (2006) A prospective study of Kaposi's sarcoma-associated herpesvirus and Epstein–Barr virus in adults with human immunodeficiency virus-1. British Journal of Cancer 94:10, 1504-1509
    CrossRef

  33. 33

    Rosamaria Tedeschi, Ettore Bidoli, Åsa Agren, Göran Hallmans, Goran Wadell, Paolo De Paoli, Joakim Dillner. (2006) Epidemiology of Kaposi's Sarcoma herpesvirus (HHV8) in Västerbotten county, Sweden. Journal of Medical Virology 78:3, 372-378
    CrossRef

  34. 34

    M.M. Chidzonga. (2006) Oral malignant neoplasia: A survey of 428 cases in two Zimbabwean hospitals. Oral Oncology 42:2, 177-183
    CrossRef

  35. 35

    Henry Kajumbula, Robert G. Wallace, Jian-Chao Zong, Joseph Hokello, Noah Sussman, Simon Simms, Robert F. Rockwell, Robert Pozos, Gary S. Hayward, William Boto. (2006) Ugandan Kaposi&rsquo;s Sarcoma-Associated Herpesvirus Phylogeny: Evidence for Cross-Ethnic Transmission of Viral Subtypes. Intervirology 49:3, 133-143
    CrossRef

  36. 36

    Gerhard Sissolak, Philippe Mayaud. (2005) AIDS-related Kaposi's sarcoma: epidemiological, diagnostic, treatment and control aspects in sub-Saharan Africa. Tropical Medicine and International Health 10:10, 981-992
    CrossRef

  37. 37

    M.R. Moosa. (2005) Kaposi's sarcoma in kidney transplant recipients: a 23-year experience. QJM 98:3, 205-214
    CrossRef

  38. 38

    W. Klaskala, B.P. Brayfield, C. Kankasa, G. Bhat, J.T. West, C.D. Mitchell, Charles Wood. (2005) Epidemiological characteristics of human herpesvirus-8 infection in a large population of antenatal women in Zambia. Journal of Medical Virology 75:1, 93-100
    CrossRef

  39. 39

    L??gia Camera Pierrotti, Arnaldo Etzel, Laura Masami Sumita, Patr??cia Emilia Braga, Jos?? Eluf-Neto, Vanda Akico Ueda Fick de Souza, Alu??sio A. Cotrim Segurado. (2005) Human Herpesvirus 8 (HHV-8) Infection in HIV/AIDS Patients From Santos, Brazil: Seroprevalence and Associated Factors. Sexually Transmitted Diseases 32:1, 57-63
    CrossRef

  40. 40

    Wen-Hui Tsai, Yuan-Ming Lee, Benjamin Ing-Tiau Kuo, Chi Kuan Ho, Pen-Tung Liao, Ming-Der Liu, Yu Ru Kou, Hui-Chi Hsu. (2005) Increased Seroprevalence of. Acta Haematologica 114:2, 95-98
    CrossRef

  41. 41

    Chun Lu, Yi Zeng, Zan Huang, Li Huang, Chao Qian, Guixia Tang, Di Qin. (2005) Human Herpesvirus 6 Activates Lytic Cycle Replication of Kaposi's Sarcoma-Associated Herpesvirus. The American Journal of Pathology 166:1, 173-183
    CrossRef

  42. 42

    A. Volpi, L. Sarmati, B. Suligoi, M. Montano, G. Rezza, M. Andreoni. (2004) Correlates of human herpes virus-8 and herpes simplex virus type 2 infections in Northern Cameroon. Journal of Medical Virology 74:3, 467-472
    CrossRef

  43. 43

    Jackson Orem, Mwanda W Otieno, Scot C Remick. (2004) AIDS-associated cancer in developing nations. Current Opinion in Oncology 16:5, 468-476
    CrossRef

  44. 44

    A Scott Laney, Sheila C Dollard, Harold W Jaffe, Margaret K Offermann, Thomas J Spira, Clifford J Gunthel, Philip E Pellett, Michael J Cannon. (2004) Repeated measures study of human herpesvirus 8 (HHV-8) DNA and antibodies in men seropositive for both HHV-8 and HIV. AIDS 18:13, 1819-1826
    CrossRef

  45. 45

    Bhavna H Chohan, Heather Taylor, Rosemary Obrigewitch, Ludo Lavreys, Barbra A Richardson, Kishorchandra N Mandaliya, Job J Bwayo, Joan K Kreiss, Rhoda Ashley Morrow. (2004) Human herpesvirus 8 seroconversion in Kenyan women by enzyme-linked immunosorbent assay and immunofluorescence assay. Journal of Clinical Virology 30:2, 137-144
    CrossRef

  46. 46

    L. Stein, H. Carrara, R. Norman, L. Alagiozoglou, L. Morris, F. Sitas. (2004) Antibodies against human herpesvirus 8 in South African renal transplant recipients and blood donors. Transplant Infectious Disease 6:2, 69-73
    CrossRef

  47. 47

    S de Sanjosé, J J Goedert, V Marshall, C Bellas, Y Benavente, R Bosch, A Domingo, A Fernandez de Sevilla, O Servitje, D Whitby. (2004) Risk of malignant lymphoma associated with human herpesvirus-8: a case–control study in Spain. British Journal of Cancer
    CrossRef

  48. 48

    ELIZABETH A. PLATZ, ANGELO M. De MARZO. (2004) Epidemiology of Inflammation and Prostate Cancer. The Journal of Urology 171:2, S36-S40
    CrossRef

  49. 49

    Miriam Margalith, Louise G. Chatlynne, Efrat Fuchs, Carole Owen, Cheng-Rei Ruth Lee, Tikva Yermiyahu, James E. Whitman, Dharam V. Ablashi. (2003) Human Herpesvirus 8 Infection Among Various Population Groups in Southern Israel. JAIDS Journal of Acquired Immune Deficiency Syndromes 34:5, 500-505
    CrossRef

  50. 50

    Patrick S. Moore, Yuan Chang. (2003) K APOSI'S S ARCOMA –A SSOCIATED H ERPESVIRUS I MMUNOEVASION AND T UMORIGENESIS : Two Sides of the Same Coin?. Annual Review of Microbiology 57:1, 609-639
    CrossRef

  51. 51

    G. Theodossiades, L. Arvanitakis, V. Tsevrenis, E. Nomikou, A. Zografidis, D. Bourboulia, I. Kontopoulou-Griva. (2003) Prevalence of Kaposi's sarcoma-associated herpesvirus infection in haemophilic patients. Haemophilia 9:5, 657-659
    CrossRef

  52. 52

    Nicole HTM Dukers, Giovanni Rezza. (2003) Human herpesvirus 8 epidemiology. AIDS 17:12, 1717-1730
    CrossRef

  53. 53

    Wolfgang Hladik, Sheila C. Dollard, Robert G. Downing, Peter Kataaha, Philip E. Pellett, John M. Karon, Jonathan Mermin, Eve M. Lackritz. (2003) Kaposi's Sarcoma in Uganda: Risk Factors for Human Herpesvirus 8 Infection Among Blood Donors. JAIDS Journal of Acquired Immune Deficiency Syndromes 33:2, 206-210
    CrossRef

  54. 54

    Sam M Mbulaiteye, D.Maxwell Parkin, Charles S Rabkin. (2003) Epidemiology of AIDS-related malignancies. Hematology/Oncology Clinics of North America 17:3, 673-696
    CrossRef

  55. 55

    Jeffrey N. Martin. (2003) Diagnosis and epidemiology of human herpesvirus 8 infection. Seminars in Hematology 40:2, 133-142
    CrossRef

  56. 56

    James J Goedert, Manhattan Charurat, William A Blattner, Ronald C Hershow, Jane Pitt, Clemente Diaz, Lynne M Mofenson, Karen Green, Howard Minkoff, Mary E Paul, David L Thomas, Denise Whitby. (2003) Risk factors for Kaposi's sarcoma-associated herpesvirus infection among HIV-1-infected pregnant women in the USA. AIDS 17:3, 425-433
    CrossRef

  57. 57

    Robert Newton, John Ziegler, Dimitra Bourboulia, Delphine Casabonne, Valerie Beral, Edward Mbidde, Lucy Carpenter, Gillian Reeves, D. Maxwell Parkin, Henry Wabinga, Sam Mbulaiteye, Harold Jaffe, , Robin Weiss, Chris Boshoff. (2003) The sero-epidemiology of Kaposi's sarcoma-associated herpesvirus (KSHV/HHV-8) in adults with cancer in Uganda. International Journal of Cancer 103:2, 226-232
    CrossRef

  58. 58

    John Ziegler, Robert Newton, Dimitra Bourboulia, Delphine Casabonne, Valerie Beral, Edward Mbidde, Lucy Carpenter, Gillian Reeves, D. Maxwell Parkin, Henry Wabinga, Sam Mbulaiteye, Harold Jaffe, , Robin Weiss, Chris Boshoff. (2003) Risk factors for Kaposi's sarcoma: A case-control study of HIV-seronegative people in Uganda. International Journal of Cancer 103:2, 233-240
    CrossRef

  59. 59

    R. M. Du Bois, N. Goh, D. McGrath, P. Cullinan. (2003) Is there a role for microorganisms in the pathogenesis of sarcoidosis?. Journal of Internal Medicine 253:1, 4-17
    CrossRef

  60. 60

    Stacia M. Desantis, Chou-pong Pau, Lennox K. Archibald, Okey C. Nwanyanwu, Peter N. Kazembe, Hamish Dobbie, William R. Jarvis, Janine Jason. (2002) Demographic and immune correlates of human herpesvirus 8 seropositivity in Malawi, Africa. International Journal of Infectious Diseases 6:4, 266-271
    CrossRef

  61. 61

    Mohamed A Eltom, Sam M Mbulaiteye, Abinbola J Dada, Denise Whitby, Robert J Biggar. (2002) Transmission of human herpesvirus 8 by sexual activity among adults in Lagos, Nigeria. AIDS 16:18, 2473-2478
    CrossRef

  62. 62

    Jasjit Gill, Dimitra Bourboulia, John Wilkinson, Peter Hayes, Alethea Cope, Anne-Genevieve Marcelin, Vincent Calvez, Frances Gotch, Christopher Boshoff, Brian Gazzard. (2002) Prospective Study of the Effects of Antiretroviral Therapy on Kaposi Sarcoma–Associated Herpesvirus Infection in Patients With and Without Kaposi Sarcoma. JAIDS Journal of Acquired Immune Deficiency Syndromes 31:4, 384-390
    CrossRef

  63. 63

    MICHEL JANIER, FÉLIX AGBALIKA, PAULINE DE LA SALMONIÈRE, FRANÇOIS LASSAU, PHILIPPE LAGRANGE, PATRICE MOREL. (2002) Human Herpesvirus 8 Seroprevalence in an STD Clinic in Paris. Sexually Transmitted Diseases 29:11, 698-702
    CrossRef

  64. 64

    Jared M Baeten, Bhavna H Chohan, Ludo Lavreys, Joel P Rakwar, Rhoda Ashley, Barbra A Richardson, Kishorchandra Mandaliya, Job J Bwayo, Joan K Kreiss. (2002) Correlates of human herpesvirus 8 seropositivity among heterosexual men in Kenya. AIDS 16:15, 2073-2078
    CrossRef

  65. 65

    R.D Cook, T.A Hodgson, E.M Molyneux, E Borgstein, S.R Porter, C.G Teo. (2002) Tracking familial transmission of Kaposi's sarcoma-associated herpesvirus using restriction fragment length polymorphism analysis of latent nuclear antigen. Journal of Virological Methods 105:2, 297-303
    CrossRef

  66. 66

    Jacques Baillargeon, Charles T. Leach, Jian-Hong Deng, Shou-Jiang Gao, Hal B. Jenson. (2002) High prevalence of human herpesvirus 8 (HHV-8) infection in south Texas children. Journal of Medical Virology 67:4, 542-548
    CrossRef

  67. 67

    JJ Hille, J Webster-Cyriaque, JM Palefski, N Raab-Traub. (2002) Mechanisms of expression of HHV8, EBV and HPV in selected HIV-associated oral lesions. Oral Diseases 8:s2, 161-168
    CrossRef

  68. 68

    Ulrich R Hengge, Thomas Ruzicka, Stephen K Tyring, Martin Stuschke, Michael Roggendorf, Robert A Schwartz, Siegfried Seeber. (2002) Update on Kaposi's sarcoma and other HHV8 associated diseases. Part 1: epidemiology, environmental predispositions, clinical manifestations, and therapy. The Lancet Infectious Diseases 2:5, 281-292
    CrossRef

  69. 69

    Slvia de Sanjos, Vickie Marshall, Judit Sol, Virgilio Palacio, Rosa Almirall, James J. Goedert, F. Xavier Bosch, Denise Whitby. (2002) Prevalence of Kaposi's sarcoma-associated herpesvirus infection in sex workers and women from the general population in Spain. International Journal of Cancer 98:1, 155-158
    CrossRef

  70. 70

    Yuan Xiao Zhu, Zhi Hua Li, Michael Voralia, A. Keith Stewart. (2002) Antigenic Open Reading Frames from HHV-8 are Present in Multiple Myeloma Patients and Normal Individuals at Similar Frequency. Leukemia & Lymphoma 43:2, 369-375
    CrossRef

  71. 71

    Lawrence Corey, Scott Brodie, Meei-Li Huang, David M. Koelle, Anna Wald. (2002) HHV-8 infection: a model for reactivation and transmission. Reviews in Medical Virology 12:1, 47-63
    CrossRef

  72. 72

    Thomas F. Schulz, Julie Sheldon, Julie Greensill. (2001) Kaposi's sarcoma associated herpesvirus (KSHV) or human herpesvirus 8 (HHV8). Virus Research 82:1-2, 115-126
    CrossRef

  73. 73

    K.H Antman. (2001) New biology and therapies in soft tissue sarcomas. Biomedicine & Pharmacotherapy 55:9-10, 553-557
    CrossRef

  74. 74

    Jacques Baillargeon, Jian-Hong Deng, Evelyn Hettler, Chantal Harrison, James J Grady, Laura G Korte, James Alexander, Eduardo Montalvo, Hal B Jenson, Shou-Jiang Gao. (2001) Seroprevalence of Kaposi's Sarcoma-Associated Herpesvirus Infection among Blood Donors from Texas. Annals of Epidemiology 11:7, 512-518
    CrossRef

  75. 75

    Attila Juhsz, va Remenyik, Jzsef Knya, Gyrgy Veress, gnes Bgny, Istvn Andirk, Ildik Medgyessy, Jnos Hunyadi, Lajos Gergely. (2001) Prevalence and age distribution of human herpesvirus-8 specific antibodies in hungarian blood donors. Journal of Medical Virology 64:4, 526-530
    CrossRef

  76. 76

    Moosa Patel, Johnny Mahlangu, Jayvant Patel, Gwynneth Stevens, Wendy Stevens, Ulrike Allard, Barry Mendelow. (2001) Kaposi Sarcoma-Associated Herpesvirus/Human Herpesvirus 8 and Multiple Myeloma in South Africa. Diagnostic Molecular Pathology 10:2, 95-99
    CrossRef

  77. 77

    G. Gambús, D. Bourboulia, A. Esteve, R. Lahoz, C. Rodriguez, F. Bolao, G. Sirera, R. Muga, J. del Romero, C. Boshoff, D. Whitby, J. Casabona. (2001) Prevalence and distribution of HHV-8 in different subpopulations, with and without HIV infection, in Spain. AIDS 15:9, 1167-1174
    CrossRef

  78. 78

    E. Papadavid, R. C. Yu, A. Katsambas, E. Koumantaki, A. C. Chu. (2001) Endemic (African) Kaposi's sarcoma presenting as a plantar tumour. Clinical and Experimental Dermatology 26:3, 266-268
    CrossRef

  79. 79

    MALIN ENBOM, ANDERS STRAND, KERSTIN I. FALK, ANNIKA LINDE. (2001) Detection of Epstein-Barr Virus, but not Human Herpesvirus 8, DNA in Cervical Secretions From Swedish Women by Real-Time Polymerase Chain Reaction. Sex Transm Dis 28:5, 300-306
    CrossRef

  80. 80

    David M Aboulafia. (2001) Kaposi’s sarcoma. Clinics in Dermatology 19:3, 269-283
    CrossRef

  81. 81

    Maha Almuneef, Shahid Nimjee, Kaveh Khoshnood, George Miller, Michael O. Rigsby. (2001) PREVALENCE OF ANTIBODIES TO HUMAN HERPESVIRUS 8 (HHV-8) IN SAUDI ARABIAN PATIENTS WITH AND WITHOUT RENAL FAILURE1234. Transplantation 71:8, 1120-1124
    CrossRef

  82. 82

    B. Davidovici, I. Karakis, D. Bourboulia, S. Ariad, J.-C. Zong, D. Benharroch, N. Dupin, R. Weiss, G. Hayward, B. Sarov, C. Boshoff. (2001) Seroepidemiology and Molecular Epidemiology of Kaposi's Sarcoma-Associated Herpesvirus Among Jewish Population Groups in Israel. JNCI Journal of the National Cancer Institute 93:3, 194-202
    CrossRef

  83. 83

    John L. Ziegler, Thierry Simonart, Robert Snoeck. (2001) Kaposi's sarcoma, oncogenic viruses, and iron. Journal of Clinical Virology 20:3, 127-130
    CrossRef

  84. 84

    C. Boshoff, Y. Chang. (2001) K APOSI ' S S ARCOMA –A SSOCIATED H ERPESVIRUS : A New DNA Tumor Virus. Annual Review of Medicine 52:1, 453-470
    CrossRef

  85. 85

    Maria J. Wawer, Sybil M. Eng, David Serwadda, Nelson K. Sewankambo, Noah Kiwanuka, Chuanjun Li, Ronald H. Gray. (2001) Prevalence of Kaposi Sarcoma-Associated Herpesvirus Compared With Selected Sexually Transmitted Diseases in Adolescents and Young Adults in Rural Rakai District, Uganda. Sex Transm Dis 28:2, 77-81
    CrossRef

  86. 86

    Laurence Gérard, Félix Agbalika, Julie Sheldon, Anne Maillard, Thomas F. Schulz, Eric Oksenhendler. (2001) No Increased Human Herpesvirus 8 Seroprevalence in Patients With HIV-Associated Non-Hodgkin's Lymphoma. JAIDS Journal of Acquired Immune Deficiency Syndromes 26:2, 182-184
    CrossRef

  87. 87

    Laurence G??rard, F??lix Agbalika, Julie Sheldon, Anne Maillard, Thomas F. Schulz, Eric Oksenhendler. (2001) No Increased Human Herpesvirus 8 Seroprevalence in Patients With HIV-Associated Non-Hodgkin's Lymphoma. Journal of Acquired Immune Deficiency Syndromes182-184
    CrossRef

  88. 88

    Eric A. Engels, Michael D. Sinclair, Robert J. Biggar, Denise Whitby, Peter Ebbesen, James J. Goedert, Joseph L. Gastwirth. (2000) Latent class analysis of human herpesvirus 8 assay performance and infection prevalence in sub-Saharan Africa and Malta. International Journal of Cancer 88:6, 1003-1008
    CrossRef

  89. 89

    Shlomi Codish, Mahmoud Abu-Shakra, Samuel Ariad, Howard J. Zirkin, Tikva Yermiyahu, Nicolas Dupin, Chris Boshoff, Shaul Sukenik. (2000) Manifestations of three HHV-8-related diseases in an HIV-negative patient: Immunoblastic variant multicentric Castleman's disease, primary effusion lymphoma, and Kaposi's sarcoma. American Journal of Hematology 65:4, 310-314
    CrossRef

  90. 90

    Pauk, John, Huang, Meei-Li, Brodie, Scott J., Wald, Anna, Koelle, David M., Schacker, Timothy, Celum, Connie, Selke, Stacy, Corey, Lawrence, . (2000) Mucosal Shedding of Human Herpesvirus 8 in Men. New England Journal of Medicine 343:19, 1369-1377
    Full Text

  91. 91

    Freddy Sitas, Rosana Pacella-Norman, Henri Carrara, Moosa Patel, Paul Ruff, Ranjan Sur, Ute Jentsch, Martin Hale, Pradeep Rowji, David Saffer, Myles Connor, Diana Bull, Robert Newton, Valerie Beral. (2000) The spectrum of HIV-1 related cancers in South Africa. International Journal of Cancer 88:3, 489-492
    CrossRef

  92. 92

    Thomas B. Campbell, Margaret Borok, Lovemore Gwanzura, Samantha MaWhinney, Irene E. White, Buxton Ndemera, Ivy Gudza, Lisa Fitzpatrick, Robert T. Schooley. (2000) Relationship of human herpesvirus 8 peripheral blood virus load and Kaposi's sarcoma clinical stage. AIDS 14:14, 2109-2116
    CrossRef

  93. 93

    C. Masini, D.D. Abeni, M.S. Cattaruzza, M. Capuano, C. Pedicelli, F. Cerimele, P. Pasquini, D. Cerimele, G. Fadda, P. Cattani. (2000) Antibodies against human herpesvirus 8 in subjects with non-venereal dermatological conditions. British Journal of Dermatology 143:3, 484-490
    CrossRef

  94. 94

    Adriana Zago, Dimitra Bourboulia, Maria Carmen Viana, Hélène Collandre, Reynaldo Dietze, Chris Boshoff, Regina Keller. (2000) Seroprevalence of Human Herpesvirus 8 and Its Association With Kaposi Sarcoma in Brazil. Sexually Transmitted Diseases 27:8, 468-472
    CrossRef

  95. 95

    Maria Mercader, Brunella Taddeo, Jeffery R. Panella, Bala Chandran, Brian J. Nickoloff, Kimberly E. Foreman. (2000) Induction of HHV-8 Lytic Cycle Replication by Inflammatory Cytokines Produced by HIV-1-Infected T Cells. The American Journal of Pathology 156:6, 1961-1971
    CrossRef

  96. 96

    Diego Serraino, Roberto Bordonaro, Giuseppe Failla, Paolo De Paoli, Paolo Colina, Rosa M. Tedeschi, Giuseppe Ippolito. (2000) Prevalence of HHV-8 infection among cancer patients in Sicily. International Journal of Cancer 86:3, 448-449
    CrossRef

  97. 97

    Marina N????ez, Ana Machuca, Vincent Soriano, Daniel Podzamczer, Juan Gonz??lez-Lahoz. (2000) Clearance of human herpesvirus type 8 viraemia in HIV-1-positive patients with Kaposi's sarcoma treated with liposomal doxorubicin. AIDS 14:8, 913-919
    CrossRef

  98. 98

    Antman, Karen, Chang, Yuan, . (2000) Kaposi's Sarcoma. New England Journal of Medicine 342:14, 1027-1038
    Full Text

  99. 99

    Eric A. Engels, Denise Whitby, P. Bradley Goebel, Andrea Stossel, David Waters, Aldo Pintus, Licinio Contu, Robert J. Biggar, James J. Goedert. (2000) Identifying Human Herpesvirus 8 Infection: Performance Characteristics of Serologic Assays. JAIDS Journal of Acquired Immune Deficiency Syndromes 23:4, 346-354
    CrossRef

  100. 100

    Eric A. Engels, Denise Whitby, P. Bradley Goebel, Andrea Stossel, David Waters, Aldo Pintus, Licinio Contu, Robert J. Biggar, James J. Goedert. (2000) Identifying Human Herpesvirus 8 Infection: Performance Characteristics of Serologic Assays. Journal of Acquired Immune Deficiency Syndromes 23:4, 346-354
    CrossRef

  101. 101

    Scott A. Stone, Evelyne T. Lennette, Joseph T. Newman, Amanda Burfoot, Marvin J. Stone. (2000) Serologic Prevalence of Antibody to Human Herpesvirus Type 8 in Patients with Various Monoclonal Gammopathies. Leukemia & Lymphoma 37:1-2, 197-203
    CrossRef

  102. 102

    Thomas B. Campbell, Lisa Fitzpatrick, Samantha MaWhinney, Xing-quan Zhang, Robert T. Schooley. (1999) Human Herpesvirus 8 (Kaposi's Sarcoma–Associated Herpesvirus) Infection in Men Receiving Treatment for HIV-1 Infection. Journal of Acquired Immune Deficiency Syndromes 22:4, 333
    CrossRef

  103. 103

    Thomas B. Campbell, Lisa Fitzpatrick, Samantha MaWhinney, Xing-quan Zhang, Robert T. Schooley. (1999) Human Herpesvirus 8 (Kaposi's Sarcoma–Associated Herpesvirus) Infection in Men Receiving Treatment for HIV-1 Infection. JAIDS Journal of Acquired Immune Deficiency Syndromes 22:4, 333
    CrossRef

  104. 104

    E. A. Engels, H. Eastman, D. V. Ablashi, R. J. Wilks, J. Braham, A. Manns. (1999) Risk of Transfusion-Associated Transmission of Human Herpesvirus 8. JNCI Journal of the National Cancer Institute 91:20, 1773-1775
    CrossRef

  105. 105

    (1999) HHV-8 Peripheral-Blood Viral Load and the Titer of Antibodies against HHV-8. New England Journal of Medicine 341:16, 1241-1242
    Full Text

  106. 106

    Karl-Josef Kallen, Peter Robert Galle, Stefan Rose-John. (1999) New developments in IL-6 dependent biology and therapy: where do we stand and what are the options?. Expert Opinion on Investigational Drugs 8:9, 1327-1349
    CrossRef

  107. 107

    V. Beral, R. Newton, F. Sitas. (1999) Human Herpesvirus 8 and Cancer. JNCI Journal of the National Cancer Institute 91:17, 1440-1441
    CrossRef

  108. 108

    Jaffe, Harold W., Pellett, Philip E., . (1999) Human Herpesvirus 8 and Kaposi's Sarcoma — Some Answers, More Questions. New England Journal of Medicine 340:24, 1912-1913
    Full Text

  109. 109

    Sitas, Freddy, , Newton, Robert, , Boshoff, Chris, . (1999) Increasing Probability of Mother-to-Child Transmission of HHV-8 with Increasing Maternal Antibody Titer for HHV-8. New England Journal of Medicine 340:24, 1923-1923
    Full Text