HHV-6 & Cancer
 HHV-6 & Glioma/Brian Tumors
 HHV-6 & Hodgkin’s Lymphoma
 HHV-6 & Non-Hodgkin’s Lymphoma
 HHV-6 & Leukemia (AML, ALL, CLL)
 HHV-6 & Cervical Cancer
Summaries and Selected Abstracts
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HHV-6 & Cancer
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HHV-6 & Cancer
HHV-6 & Glioma/Brain Tumors
Investigators from Nanjing Medical University led by Dr. Kun Yao have recently found
HHV-6 latent infection in glioma tissues, and have isolated a strain of HHV-6A from the
glioma cyst, supporting earlier studies that suggest the involvement of HHV-6 in the
pathogenesis of adult and pediatric gliomas. Using nested PCR and immunohistochemistry, Dr.
Yao’s team identified HHV-6 DNA and protein in tissue from 42.5% of gliomas compared to
7.7% of normal brain tissue. In addition, elevated levels of several cytokines that were
specifically promoted by HHV-6 infection in astrocyte cultures were also observed in HHV-6positive cyst fluid samples from glioma tissues.
An earlier paper by NINDS/NIH investigators (Crawford 2009) found that both early
(p41) and late (gp116/64/54) HHV-6 viral antigens were detected three times more frequently in
adult glial tumors compared to control brain tissues. An additional study by this group utilized
nested PCR, in situ hybridization (ISH), and IHC to detect HHV-6 in pediatric brain tumors,
and demonstrated that HHV-6 viral antigens were significantly correlated with low gradeglioma tissues compared to controls (Crawford 2009).
The authors note that “proinflammatory cytokines induced by HHV-6 infection might
provide a chronic inflammatory environment that facilitates the development of glioma” by
altering the properties of the infected cell and inducing proinflammatory cytokine secretion—as
has been documented previously (Yoshikawa 2002). This suggests HHV-6 may directly
facilitate the pathogenesis of glioma. In addition, the authors suggest that selective
immunosuppression caused by HHV-6 infection can lead to the disruption of key immune
activation pathways, perhaps further contributing to the pathogenesis of glioma.
Selected Abstracts
Human Herpesvirus 6 Latent Infection in Patients With Glioma.
Chi J, Gu B, Zhang C, Peng G, Zhou F, Chen Y, Zhang G, Guo Y, Guo D, Qin J, Wang J, Li L, Wang F, Liu G,
Xie F, Feng D, Zhou H. Huang X, Lu S, Liu Y, Hu W, Yao K. Department of Microbiology and Immunology,
Nanjing Medical University, Jiangsu Province, China. J Infect Dis. 2012 Sept.
The etiology of glioma remains unclear so far. Human herpesvirus 6 (HHV-6) might be associated with glioma, but there
is no direct evidence to support this. High percentages of HHV-6 DNA and protein were detected in tissue from gliomas,
compared with normal brain tissue. In addition, a strain of HHV-6A was isolated from the fluid specimens from glioma
cysts. High levels of interleukin 6 (IL-6), interleukin 8 (IL-8), tumor necrosis factor α, and transforming growth factor β
(TGF-β) were detected in the cyst fluid specimens from HHV-6-positive patients with glioma. Furthermore, HHV-6A
infection promoted IL-6, IL-8, and TGF-β production in astrocyte cultures. Our studies strongly suggest the involvement
of HHV-6 infection in the pathogenesis of glioma.
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Detection of human herpesvirus-6 in adult central nervous system tumors:
predominance of early and late viral antigens in glial tumors.
Crawford JR, Santi MR, Cornelison R, Sallinen SL, Haapasalo H, MacDonald TJ.
Department of Neurology, The George Washington University, Washington, DC 20010, USA.
J Neurooncol. 2009 Oct;95(1):49-60.
The purpose is to determine the incidence of active and latent human herpesvirus-6 (HHV-6) infection in a large cohort of
adult primary and recurrent CNS tumors. We screened a tissue microarray (TMA) containing more than 200 adult primary
and recurrent CNS tumors with known clinical information for the presence of HHV-6 DNA by in situ hybridization
(ISH) and protein by immunohistochemistry (IHC). One hundred six of 224 (47%) CNS tumors were positive for HHV-6
U57 Major Capsid Protein (MCP) gene by ISH compared to 0/25 non tumor control brain (P = 0.001). Fourteen of 30
(47%) tumors were HHV-6 MCP positive by nested PCR compared to 0/25 non-tumor brain controls (P = 0.001),
revealing HHV-6 Variant A in 6 of 14 samples. HHV-6A/B early (p41) and late (gp116/64/54) antigens were detected by
IHC in 66 of 277 (24%) (P = 0.003) and 84 of 282 (35%) (P = 0.002) tumors, respectively, suggesting active infection.
HHV-6 p41 (P = 0.645) and gp116/64/54 (P = 0.198) antigen detection was independent of recurrent disease. Glial
tumors were 3 times more positive by IHC compared to non glial tumors for both HHV-6 gp116/64/54 (P = 0.0002)
and HHV-6 p41 (P = 0.004). Kaplan Meier survival analysis showed no effect of HHV-6 gp116/64/54 (P = 0.852) or
HHV-6 p41 (P = 0.817) antigen detection on survival. HHV-6 early and late antigens are detected in adult primary and
recurrent CNS tumors more frequently in glial tumors. We hypothesize that the glial-tropic features of HHV-6 may play
an important modifying role in tumor biology that warrants further investigation.
Detection of human herpesvirus-6 variants in pediatric brain tumors:
association of viral antigen in low grade gliomas.
Crawford JR, Santi MR, Thorarinsdottir HK, Cornelison R, Rushing EJ, Zhang H, Yao K, Jacobson S,
Macdonald TJ. The Department of Neurology, Children's National Medical Center, The George Washington
University, Washington DC, USA. J Clin Virol. 2009 Sep;46(1):37-42.
BACKGROUND: Human herpesvirus-6 (HHV-6) has been associated with a diverse spectrum of central nervous system
(CNS) diseases and reported glial tropism.
OBJECTIVE: To determine if HHV-6 is present in a series of pediatric brain tumors.
STUDY DESIGN: Pediatric gliomas from 88 untreated patients represented in a tissue microarray (TMA) were screened
for HHV-6 by nested polymerase chain reaction (PCR), in situ hybridization (ISH), and immunohistochemistry (IHC) and
compared to non-glial tumors (N=22) and control brain (N=32). Results were correlated with tumor grade and overall
survival.
RESULTS: HHV-6 U57 was detected by nested PCR in 68/120 (57%) tumors and 7/32 (22%) age-matched non-tumor
brain (P=0.001). HHV-6 U31 was positive in 73/120 (61%) tumors and 11/32 (34%) controls (P=0.019). Seventy-two
percent (43/60) of tumors were HHV-6 Variant A. HHV-6 U57 was confirmed by ISH in 83/150 (54%) tumors and 10/32
(31%) controls (P=0.021), revealing a non-lymphocytic origin of HHV-6. HHV-6A/B gp116/64/54 late antigen was
detected by IHC in 50/124 (40%) tumors and 6/32 (18%) controls (P=0.013). Interestingly, 58% of low grade gliomas
(N=67) were IHC positive compared to 19% of high grade gliomas (N=21, P=0.002) and 25% of non-gliomas (N=36,
P=0.001). HHV-6A/B gp116/64/54 antigen co-localized with glial fibrillary acidic protein, confirming the astrocytic
origin of antigen. Overall, there was no primary association between HHV-6A/B gp116/64/54 antigen detection and
survival (P=0.861).
CONCLUSIONS: We provide the first reported series of HHV-6 detection in pediatric brain tumors. The predominance
of HHV-6 in glial tumors warrants further investigation into potential neurooncologic disease mechanisms.
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HHV-6 & Cancer
HHV-6 & Hodgkin’s Lymphoma
There have been numerous studies aimed at finding an association between HHV-6 and
Hodgkin’s Disease (HD), and it has proven very difficult to conclude definitively on this
subject due to the difference in assays and patients tested. However, a link between HHV-6 and
the nodular sclerosis subtype of Hodgkin’s lymphoma (NSHL) has recently been reinforced by
several groups. A new study from Yale has identified HHV-6 in 86% of NSHL cases.
Researchers utilized several laboratory methods—including IHC, PCR, and FISH—to identify
HHV-6 DNA in tissue samples from 31 lymph node cases of Hodgkin’s lymphoma. In
addition, the group also sought to localize the presence of HHV-6 DNA in particular HL cell
types, and identified HHV-6 DNA via IHC in malignant Reed-Sternberg cells in nearly half of
the cases. This result, which is supported by previously published work by Lacroix et al and
others, suggests that HHV-6 may play a direct role in the pathogenesis of NSHL. The study is
the most comprehensive and thorough investigation conducted on the association between
HHV-6 & NHSL to date, and helps to clarify previously conflicting results published in the
field.
Lacroix and colleagues found that HHV-6 is more frequently detected in the nodular
sclerosis subset of HD: of 73 patients with nodular sclerosis, 39 (49%) were positive for both
HHV-6 and EBV DNA, 25 (34%) had only HHV-6 and 8 (11%) had only EBV. However, of 10
cases of the mixed cellularity form of HD, 4 (40 %) had both viruses, 1 had HHV-6 only, 4 had
EBV only, and 1 had neither (Lacroix 2007). Whether as-yet-uncharacterized proteins may be
expressed in HD tissues remains to be explored.
Selected Abstracts
Human herpesvirus 6 positive Reed-Sternberg cells in nodular sclerosis
Hodgkin lymphoma
Siddon A, Lozovatsky L, Mohamed A, Hudnall SD. Department of Pathology, Yale University School of
Medicine, New Haven, CT, USA. Br J Haematol. 2012 Sep;158(5):635-43.
Classical Hodgkin lymphoma (HL) exhibits a bi-modal age distribution that suggests an infectious aetiology. However,
most cases of nodular sclerosis HL (NSHL) are Epstein-Barr virus (EBV) negative (60-90%). Previous studies regarding
human herpesvirus 6 (HHV-6) positivity of HL have led to conflicting results. In order to clarify this situation, we
examined NSHL biopsies for the presence and distribution of HHV-6 by immunohistochemistry (IHC), polymerase chain
reaction (PCR), and fluorescence in situ hybridization (FISH). PCR identified HHV-6 DNA in 86% of NSHL cases. As
HHV-6 DNA was also identified in most cases of reactive lymphoid hyperplasia, we sought to localize the virus to
specific cells by IHC, which detected HHV-6 in Reed-Sternberg (RS) cells of nearly half (48%) of NSHL cases. Dual
CD30/HHV-6 immunostaining confirmed HHV-6 immunoreactivity in CD30+ RS cells, and HHV-6 PCR positivity was
confirmed in laser capture microdissection-isolated CD30+ RS cells. FISH demonstrated multiple copies of HHV-6
genome in scattered cells. In contrast, EBV+ RS cells were identified in only 24% of the cases. HHV-6+ cases trended
toward a younger age than EBV+ cases. These results conclusively demonstrate that RS cells in many cases of NSHL are
HHV-6 positive, and suggest that HHV-6 may play a role in NSHL pathogenesis, particularly in younger patients with
EBV-negative
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HHV-6 & Cancer
Involvement of human herpesvirus-6 variant B in classic Hodgkin's lymphoma
via DR7 oncoprotein.
Lacroix A, Collot-Teixeira S, Mardivirin L, Jaccard A, Petit B, Piguet C, Sturtz F, Preux PM, Bordessoule D,
Ranger-Rogez S. Centre Hospitalier Universitaire Dupuytren, Limoges, France. 2010 Oct 1;16(19):4711-21.
Epub 2010 Sep 21.
PURPOSE: Hodgkin's lymphoma (HL) is associated with the presence of EBV in Reed-Sternberg (RS) cells in ∼40% of
cases. Here, we studied the presence of human herpesvirus type 6 (HHV-6) variant B in RS cells of HL patients and
correlated results with clinical parameters. We then examined the implication of HHV-6 DR7B protein in cell
deregulation.
EXPERIMENTAL DESIGN: HHV-6 DR7B protein was produced in a Semliki Forest virus system. Polyclonal
antibodies were then generated and used for immunochemical HHV-6 localization in HL biopsies. Binding between
DR7B and p53 was studied using a double-hybrid system. Transactivation of NFκB was observed after transient
transfection using reporter gene assays. We looked for Id2 factor expression after stable transfection of the BJAB cell line
by reverse transcription-PCR and Western blot analysis.
RESULTS: HHV-6 was more common in nodular sclerosis subtype HL, and DR7B oncoprotein was detected in RS cells
for 73.7% of EBV-negative patients. Colocalization of EBV and HHV-6 was observed in RS cells of doubly infected
patients. DR7B protein bound to human p53 protein. p105-p50/p65 mRNA expression and activation of the NFκB
complex were increased when DR7B was expressed. Stable expression of DR7B exhibited a strong and uniform
expression of Id2. A slightly higher percentage of remission was observed in patients with RS cells testing positive for
DR7B than in those testing negative.
CONCLUSIONS: Collectively, these data provide evidence for the implication of a novel agent, HHV-6, in cases of
nodular sclerosis HL.
HHV-6 and EBV DNA quantitation in lymph nodes of 86 patients with
Hodgkin's lymphoma.
Lacroix A, Jaccard A, Rouzioux C, Piguet C, Petit B, Bordessoule D, Ranger-Rogez S. Laboratoire de
Microbiologie, EA 4021, Faculté de Pharmacie, Limoges, France. J Med Virol. 2007 Sep;79(9):1349-56.
Human herpesvirus (HHV-6) and Epstein-Barr virus (EBV), are two ubiquitous human herpesviruses which share many
common features although they belong to different sub-families. In particular, both viruses are found in lymph nodes of
patients suffering from Hodgkin's lymphoma. The aim of this study was to detect and to quantify independently HHV-6
and EBV by a real-time PCR in lymph nodes from 86 patients with Hodgkin's lymphoma. EBV quantitative method was
compared with LMP-1 protein detection among the same samples. EBV genome was detected for 61.6% of the patients
(53/86) and the highest prevalence of this virus was observed in Hodgkin's lymphoma with mixed-cellularity
histopathological type (80%). In contrast to that, HHV-6 genome was detected for 79.1% of the patients (68/86) and was
most observed in the nodular-sclerosis group (83.6%). Among the 68 HHV-6 positive samples, 63 belonged to the B
subtype. A large number of biopsies (47.7%) were positive for both viruses whereas a little number (7%) was negative for
both. EBV quantitation and LMP-1 immunohistochemistry were correlated statistically but this latter technique was less
sensitive. Among the nodular-sclerosis patients, HHV-6-/EBV+ patients were significatively older than HHV-6+/EBVpatients. Patients infected dually had higher values of quantitation for each virus than those positive for one virus. Data of
the clinical follow-up obtained by diagnosis and during the treatment of 83 patients, were correlated with the virological
findings.
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HHV-6 & Cancer
HHV-6 & Non-Hodgkin’s Lymphoma
Luppi et al. (1993), reported finding a higher frequency of HHV-6 DNA in a well
characterized series of patients with angioimmunoblastic T cell lymphoma (AITL), a subtype of
T-cell non-Hodgkin’s lymphoma, compared with other lymphoma subtypes and controls. These
findings have been confirmed by Zhou et al., (Zhou 2007) showing a clear association between
histological progression of AITL and the detectable copy number of both EBV and HHV-6 B in
the AITL lesional tissue. While this increased viral load could reflect a role for HHV-6 in the
pathogenesis and progression of AITL, it also could be the consequence of increasing
dysfunction of the immune system during lymphoma progression. Immunohistochemical
studies have so far failed to demonstrate HHV-6 antigens in the CD4 positive T cells (the likely
proliferating elements) within AITL lesions.
Selected Abstracts
Angioimmunoblastic T-cell lymphoma: histological progression associates
with EBV and HHV6B viral load.
Zhou Y, Attygalle AD, Chuang SS, Diss T, Ye H, Liu H, Hamoudi RA, Munson P, Bacon CM, Dogan A, Du MQ.
Department of Pathology, University of Cambridge, Cambridge, UK. Br J Haematol. 2007 Jul;138(1):44-53.
The clinical and histological presentations of angioimmunoblastic T-cell lymphoma (AITL) often mimic an infectious
process. Epstein-Barr virus (EBV) and human herpes virus (HHV6) are known to be associated with AITL, but whether
these viral infections play a role in its pathogenesis is unclear. It also remains to be investigated whether there might be
other viruses associated with AITL. We first screened 26 well-characterised cases of AITL for herpesvirus by polymerase
chain reaction (PCR) with universal primers and found evidence of only EBV and HHV6B infection. Subsequent PCR
using virus-specific primers demonstrated EBV and HHV6B infection in 40/49 biopsies (36/42 cases) and 21/49 biopsies
(19/42 cases) of AITL respectively with both viral infections found in 17/49 specimens (15/42 cases). Importantly,
simultaneous infection with both viruses was found only in specimens showing histological pattern II (n = 2) or III (n =
15). Interestingly, among specimens containing both viruses, there was a tendency towards an inverse correlation between
the EBV and HHV6B viral load as shown by quantitative PCR. In specimens positive only forEBV, the viral load was
significantly higher in specimens with histological pattern III than those with pattern II. High EBV load was also
significantly associated with B-cell monoclonality. Double EBV encoded small RNA (EBER) in situ hybridisation and
immunohistochemistry indicated that EBV-infected B cells had a late postgerminal centre immunophenotype. Our results
demonstrate an association between EBV and HHV6B infection and the histological progression of AITL, suggesting that
these viruses may play a role in the pathogenesis of this lymphoma.
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HHV-6 & Cancer
Presence of Human Herpes Virus 6 (HHV6) in pediatric lymphomas: impact
on clinical course and association with cytomegalovirus infection.
Loutfy A, Fawzy M, El-Wakil M, Moneer M. Virology & Immunology Unit, Cancer Biology Department,
National Cancer Institute, Cairo University, Egypt. Virol J. 2010 Oct 27;7:287.
BACKGROUND: Activation of herpes virus 6 (HHV6) has seen in Hodgkin's and non-Hodgkin's Lymphoma
(HL&NHL) as a result of lymphoma associated immunosuppression. Multiple studies have suggested an association
between both HHV6 and cytomegalovirus CMV for development of CMV disease affecting the pathogenesis of
lymphoma. Therefore, this study investigated the frequency of HHV6, its impact on clinical manifestations of lymphoma
and its possible association with risk for development of CMV infection in pediatric lymphoma patients.
METHODS: Presence of HHV6 DNA and CMV DNA was investigated by PCR assay in both WBC's and plasma
samples from 50 patients diagnosed with HL or NHL. CMV antibody titer was also determined in sera obtained from each
patient. Twenty apparently healthy siblings were used as a control group.
RESULTS: In a study group of 50 patients diagnosed with HL or NHL, 23/50 (46%) were found to be positive for herpes
virus DNA (HHV6 or CMV) in WBC's or plasma by PCR assay and this was significantly higher than its presence in the
pediatric control group 2/20 (10%) (p = 0.005). Ten out of these 23 (43%) were found to have active CMV infection. Fifty
six percent of patients with CMV infection were found among NHL cases with B- subtype. The presence of both herpes
viruses DNA was significantly associated with more frequent episodes of febrile neutropenia (median 3 episodes),
absolute neutrophil count (< 0.8), lymphocytes (< 0.5), and low hemoglobin level (< 9.1), (p < 0.05).
CONCLUSION: The presence of HHV6 can be considered as a predicting indicator of cellular immunosuppression
preceding the onset of CMV infection which may result in a severe outcome among pediatric lymphoma patients.
Frequent detection of human herpesvirus-6 sequences by polymerase chain
reaction in paraffin-embedded lymph nodes from patients with angioimmunoblastic lymphadenopathy and angioimmunoblastic lymphadenopathylike lymphoma.
Luppi M, Marasca R, Barozzi P, Artusi T, Torelli G. Centre for Experimental Haematology, Second Medical
Clinic, University of Modena, Italy. Leuk Res. 1993 Nov;17(11):1003-11.
In search of a possible involvement of viral agents in angioimmunoblastic lymphadenopathy with dysproteinaemia
(AILD) and AILD-like lymphoma(AILD-L), we studied the presence of human herpesvirus-6 (HHV-6) in the lymph node
biopsies of 12 cases by polymerase chain reaction (PCR). Given the rarity of this lymphoproliferative disorder, we
investigated archival specimens, consisting of formalin-fixed and paraffin-embedded tissues, obtained from patients with
a clinical and histologic diagnosis of AILD and AILD-L. HHV-6 sequences were detected in the lymph node biopsies of 7
out of the 12 AILD and AILD-L cases examined. HHV-6 sequences were identified also in the involved liver and spleen
tissues of one patient and in the PBMCs of two patients, all carrying viral sequences in the affected lymph nodes. We also
used PCR to characterize the HHV-6 genomes, showing that two different viral strains are represented in the pathologic
tissues. This study provides evidence of the presence of HHV-6 specific sequences in an unexpectedly high proportion of
our series of AILD and AILD-L cases, suggesting a possible involvement of this lymphotropic virus in the pathogenesis
of at least some cases of the disease.
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HHV-6 & Cancer
HHV-6 & Leukemia (AML, ALL, CLL)
Persistent IL-2 regulated HHV-6 infection of adult T-cell leukemia cells causes T cell leukemia to
progress more rapidly (Ojima 2005), but in vivo studies have not yet confirmed a pathogenetic role for HHV-6
in this disease. Studies of the role of HHV-6 in acute leukemia are mixed. HHV-6 antibody titers may be higher
in patients with acute myeloid leukemia (AML) but not with acute lymphoblastic leukemia (ALL) (Gentile
1999). Salonen et al found that 40% of children with leukemia had IgM antibodies to HHV-6 compared to
7.7% of reference subjects. (Salonen 2002). However, molecular studies have so far failed to show a higher rate
of HHV-6 DNA in children with ALL compared with healthy subjects (Barozzi 1995). Although a more recent
report found higher rates of seropositivity to human cytomegalovirus (HCMV) among patients with B cell
chronic lymphocytic leukemia (CLL) than among healthy control subjects, the same was not true for
seropositivity to HHV-6 (or EBV and HHV-7) (Steininger 2009). Recent studies suggest that HHV-6 (along
with CMV and EBV) reactivation occurs frequently among patients receiving cytotoxic chemotherapy for adult
T cell leukemia (Ogata 2011). In conclusion, with the possible exception of adult T-cell leukemia, available
data do not lend support to a role for HHV-6 in human acute leukemias.
Selected Abstracts
High incidence of cytomegalovirus, human herpesvirus-6, and Epstein-Barr virus reactivation in patients
receiving cytotoxic chemotherapy for adult T cell leukemia.
Ogata M, Satou T, Kawano R, Yoshikawa T, Ikewaki J, Kohno K, Ando T, Miyazaki Y, Ohtsuka E, Saburi Y,
Kikuchi H, Saikawa T, Kadota J. Oita University Hospital, Oita, Japan. J Med Virol. 2011 Apr;83(4):702-9.
The etiology of cytomegalovirus (CMV), human herpesvirus-6 (HHV-6), and Epstein-Barr virus (EBV) reactivation and
the potential for complications following cytotoxic chemotherapy in the absence of allogeneic transplantation are not
clearly understood. Patients with adult T cell leukemia (ATL) are susceptible to opportunistic infections. In this study, the
incidence, kinetics and clinical significance of reactivation of CMV, HHV-6, and EBV in ATL patients were investigated.
Viral DNA in a total of 468 plasma samples from 34 patients was quantified using real-time PCR. The probability of
CMV, HHV-6, and EBV reactivation by 100 days after the start of chemotherapy was 50.6%, 52.3%, and 21.6%,
respectively. Although most CMV reactivations were self-limited, plasma CMV DNA tended to persist or increase if the
CMV DNA levels in plasma reached ≥ 10(4) copies/ml. CMV reactivation was negatively associated with survival, but
the P-value for this association was near the borderline of statistical significance (P=0.052). One patient developed fatal
interstitial pneumonia concomitant with peak CMV DNA accumulation (1.6 × 10(6) copies/ml plasma). Most HHV-6
and EBV reactivations were self-limited, and no disease resulting from HHV-6 or EBV was confirmed. HHV-6 and EBV
reactivation were not associated with reduced survival (P=0.35 and 0.11, respectively). These findings demonstrated that
subclinical reactivation of CMV, HHV-6, and EBV were common in ATL patients receiving chemotherapy. There were
differences in the viral reactivation patterns among the three viruses. A CMV load ≥ 10(4) copies/ml plasma was
indicative of subsequent exacerbation of CMV reactivation and developing serious clinical course.
Relative seroprevalence of human herpes viruses in patients with chronic lymphocytic leukaemia.
Steininger C, Rassenti LZ, Vanura K, Eigenberger K, Jager U, Kipps TJ, Mannhalter C, Stilgenbauer S,
Popow-Kraupp T. Department of Medicine, Medical University of Vienna, Vienna, Austria. Eur J Clin Invest.
2009 Jun;39(6):497-506.
BACKGROUND: Herpes virus infections may have a significant role in chronic lymphocytic leukaemia (CLL) due to
their ability to modulate the host's immune system.
MATERIALS AND METHODS: We examined the seroprevalence of four herpes viruses [Cytomegalovirus (CMV),
Epstein-Barr Virus (EBV), human herpes virus (HHV)-6 and -7] in a cohort of European CLL patients (cohort 1, n = 100)
in relation to the immunoglobulin variable heavy (IGHV) chain gene use and compared serological results with those
obtained from age- and gender-matched healthy adults (n = 100).
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RESULTS: CMV-seroprevalence was significantly higher in CLL cohort 1 (79%) than in the control cohort (57%, P =
0.001); the seroprevalence of EBV (89% vs. 94%), HHV-6 (73% vs. 60%), or HHV-7 (35% vs. 35%) was not. In CLL
cohort 1, use of IGHV3-30 was more prevalent among CMV-seropositive and of IGHV3-21 among HHV-7-seronegative
cases. To investigate the generalizability of these findings, we investigated the herpes virus seroprevalence in a second
cohort of age-matched CLL patients from a different geographical area (USA, n = 100, cohort 2). In cohort 2, CMVseroprevalence was comparable with that of the control cohort (53%). Seroprevalence of EBV, HHV-6 and HHV-7 were
85%, 88% and 73% respectively. In CLL cohort 2, use of IGHV3-30 or IGHV3-21 was not associated with any of the
herpes viruses investigated.
CONCLUSIONS: CMV-seropositivity is associated with CLL in selected patient cohorts. However, the considerable
variation in herpes virus-specific seropositivity between geographically distinct CLL cohorts indicates that seropositivity
for any of the four human herpes viruses investigated is not generally associated with CLL.
IL-2-regulated persistent human herpesvirus-6B infection facilitates growth of adult T cell leukemia cells.
Ojima T, Abe K, Ohyashiki JH, Shirakata M, Yamamoto K. Department of Virology, Medical Research Institute,
Tokyo Medical and Dental University, Japan. J Med Dent Sci. 2005 Jun;52(2):135-41.
Human herpesvirus-6B (HHV-6B), a causative agent of exanthem subitum, infects human adult T cell leukemia (ATL)
cell lines. We established a persistent HHV-6B infection in an ATL cell line, TaY, in the presence of 20 units/ml
interleukin-2 (IL-2). The HHV-6B infected culture proliferated with a constant ratio of infected (1%) to the uninfected
(99%) cells. When the IL-2 concentration was reduced to 5 units/ml, the number of infected cells in the culture increased
transiently by 60% in 11 days, a new balance of 25% infected cells and 75% uninfected cells was established thereafter.
PCR analysis confirmed a 125-fold increase in the amount of viral genome in the culture, while the treatment with
ganciclovir reduced the proportion of infected cells, indicating that an efficient replication of virus was induced in the
culture. Both of these cultures were maintained in the presence of 20 or 5 units/ml IL-2 over one year without loss of
infected cells. Interestingly, we found that cultures containing the infected cells grew significantly faster than the parental
uninfected cells at the same concentration of IL-2. The infected culture continued to grow for 7 days even in the absence
of IL-2. Because the infection induces cell cycle arrest, these results indicate that the HHV-6B-infected ATL cells
stimulate the growth of the uninfected cells during persistent infection in culture.
Antibody status to HHV-6 in children with leukaemia.
Salonen MJ, Siimes MA, Salonen EM, Vaheri A, Koskiniemi M. Haartman Institute, Department of Virology,
University of Helsinki, Helsinki, Finland. Leukemia. 2002 Apr;16(4):716-9.
Forty children with acute lymphoblastic (33) or myeloid leukaemia (seven) were studied for IgG and IgM antibodies and
IgG avidity against human herpesvirus 6 (HHV-6) at the time of diagnosis, and compared with age-, sex- and seasonmatched children with various neurological diseases of suspected viral origin. Of the children with leukaemia, 97.5% had
IgG antibodies and 40% IgM antibodies to HHV-6 compared with 92.3% and 7.7% of reference subjects (P = 0.005). A
seronegative child with leukaemia seroconverted 3 weeks after the diagnosis. The avidity of IgG antibodies (based on the
resistance to urea treatment) was high in all children with leukaemia. One reference child had HHV-6-specific IgG
antibodies with low avidity, which together with his positive IgM indicated an acute infection. The presence of specific
IgM antibodies in 40% of children with leukaemia and the high avidity of IgG suggest a reactivation or an inaproppriate
primary response to HHV-6 infection. The results support the conclusion of the role of the HHV-6 infection at the onset of
childhood leukaemia.
Human herpes virus-6 seroprevalence and leukaemias: a case-control study. GIMEMA (Gruppo Italiano Malattie
Ematologiche dell' Adulto).
Gentile G, Mele A, Ragona G, Faggioni A, Zompetta C, Tosti ME, Visani G, Castelli G, Pulsoni A, Monarca B, Martino
P, Mandelli F. Dipartimento di Biotecnologie Cellulari e Ematologia, Università La Sapienza, Rome, Italy. Br J Cancer.
1999 Jun;80(7):1103-6.
The relationships between acute myeloid leukaemia (AML), acute lymphocytic leukaemia (ALL), chronic myeloid
leukaemia (CML) and refractory anaemia with excess of blasts (RAEB) and human herpes virus (HHV)-6 antibody level
were investigated in a multicentre case-control study. An association between increased HHV-6 seropositivity and
geometric mean titre ratio with AML was shown: P for trend = 0.022, adjusted odds ratio 1.20, 95% confidence interval
1.07-1.33 respectively. No association was found between HHV-6 and ALL, CML or RAEB.
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HHV-6 & Cancer
HHV-6 & Cervical Cancer
It is well established that Human papillomaviruses (HPVs) are necessary, yet not sufficient, for the
development of cervical cancer; and many essential cofactors have been implicated in the progression of this
disease. Some authors have suggested a role for several human herpesviruses—namely EBV and CMV—in the
development of cervical cancer, particularly through co-infection with HPV and subsequent interaction with the
HPV-16 genome (Szostek 2009). Multiple studies have detected HHV-6/HPV co-infection among samples from
women with cervical cancer (Chen 2001, Tran-Thanh 2002). In one study that primarily focused on new assay
development, HHV-6B was detected in a patient who later developed cervical cancer (Li 2009). However, in
2001 Chen et al concluded HHV-6 likely acted as a bystander, rather than a cofactor, in the pathogenesis of
cervical cancer.
In 2008, Broccolo et al found that the prevalence of HHV-6 DNA was significantly higher in high-grade
squamous intraepithelial lesions (HSIL)—a known precursor to cervical cancer—compared to samples from
healthy women. In addition, co-presence of CMV and HHV-6 DNA was significantly higher in patients with
SIL compared to controls. These findings suggest that HHV-6 alone or together with CMV may contribute to
the development of cervical cancer (Broccolo 2008).
Selected Abstracts
Herpesviruses as possible cofactors in HPV-16-related oncogenesis.
Szostek S, Zawlinska B, Kopec J, Kosz-Vnenchak M. Department of Virology, Jagiellonian University Medical
College, Kraków, Poland. Acta Biochim Pol. 2009;56(2):337-42. Epub 2009 Jun 4.
Cervical carcinogenesis is a complex problem with papillomavirus widely accepted as a causative agent. Integration of a
human papillomavirus (HPV) of the high-risk type into the host cell genome is one of the major contributing factors to
cervical malignant transformation. In this study, the correlation of CMV, EBV, HSV-1, HSV-2, HHV-6 and HHV-7
infections with the physical status of the HPV genome in cervical cancer and precancerous cervical lesions was
investigated in sixty HPV-16-positive women. Cervical secretion samples were submitted to DNA extraction and
analyzed by PCR. HPV-16 DNA was confirmed in genotyping with the reverse hybridization line probe assay. Multiplex
PCR with specific primers for the E2/E6 genes was used to assess the viral integration status of HPV-16. Our results show
that CMV DNA was more frequently present in samples with mixed forms of HPV-16 than in the episomal form (P <
0.025). Such a correlation was also observed in the case of EBV (P < 0.005). The presence of CMV resulted in a six-fold
(OR 6.069; 95% CI 1.91-19.22; P = 0.002), while EBV caused a seven-fold (OR 7.11; 95% CI 1.70-29.67; P = 0.007)
increase in the risk of the integrated or mixed HPV-16 genome occurrence. Our data suggest that coinfection with
herpesviruses, especially CMV and EBV, may be involved in the integration of the HPV-16 genome and may contribute
to the development of cervical cancer.
Frequency and clinical significance of human beta-herpesviruses in cervical samples from Italian women.
Broccolo F, Cassina G, Chiari S, Garcia-Parra R, Villa A, Leone BE, Brenna A, Locatelli G, Mangioni C,
Cocuzza CE. Department of Clinical Medicine and Prevention, University of Milano-Bicocca, Monza, Italy. J
Med Virol. 2008 Jan;80(1):147-53.
Human papillomaviruses (HPVs) are necessary, but not sufficient, for the development of cervical cancer (CC). Human
beta-herpesviruses (beta-HHVs) have been suggested as possible cofactors in the oncogenesis of CC. In this crosssectional study, the prevalence and possible association of cytomegalovirus (CMV), HHV-6 and -7 with HPV presence
was investigated by quantitative real-time PCR assays in cervical samples obtained from 208 italian women. The two
most common high-risk HPV types found were 31 and 16. Overall, the positive rates for CMV, HHV-6 and HHV-7 were
66%, 25%, and 6%, respectively. In particular, the prevalence of CMV was found to be extremely high irrespective of
either the cytological category or HPV positivity. The prevalence of HHV-6 DNA was significantly higher in high-grade
squamous intraepithelial lesions (HSIL) respect to normal women (P < 0.017); by contrast, the prevalence HHV-7 DNA
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HHV-6 & Cancer
was generally low and not associated with SIL. Copresence of CMV and HHV-6DNA was found to be significantly
higher in patients with SIL respect to normal women (P < 0.05). No correlation was demonstrated between the viral load
of all three beta-HHVs and the different cytological stages or with the HPV presence. A few patients with severe disease
however showed very high viral loads which for HHV-6 may be indicative of viral integration. In conclusion, this study
suggests that CMV and HHV-7 alone are probably not implicated in the oncogenesis of CC whilst HHV-6 alone or
together with CMV may contribute to the development of CC.
Detection of human herpes virus type 6 DNA in precancerous lesions of the uterine cervix.
Tran-Thanh D, Koushik A, Provencher D, Drouin P, Dubuc-Lissoir J, Gauthier P, Allaire G, Kornegay J,
Franco E, Coutlee F. Départements de Microbiologie Médicale et Infectiologie, Gynécologie-Obstétrique et
Pathologie, Université de Montréal, Montréal, Qué., Canada. J Med Virol. 2002 Dec;68(4):606-10.
Human herpes virus type 6 (HHV-6) DNA has been suggested to be a cofactor to human papillomavirus (HPV) in cervical
cancer. In a cross-sectional study, we investigated the association between HHV-6 DNA detected in cervical brushings
and high-grade squamous intraepithelial lesions (HSIL), while controlling for genital infection with 27 genotypes of HPV.
Of the 320 women recruited from an oncologic gynecology clinic, 50 had invasive cervical cancer, 65 had HSIL, 80 had
low-grade squamous intraepithelial lesions (LSIL), and 125 were normal. Four of the seven HHV-6-positive women had
HSIL. HHV-6 was associated with HSIL after adjusting for age and socioeconomic status (odds ratio [OR] of 10.9, 95%
confidence interval [CI]: 1.1-107.1). This association was no longer significant after controlling for HPV (OR = 6.4, 95%
CI = 0.3-128.5). HHV-6 was detected in cervical samples from women with precancerous and cancerous lesions of the
cervix, but not significantly more frequently than in normal women.
Association of human beta-herpesvirus with the development of cervical cancer: bystanders or cofactors.
Chan PK, Chan MY, Li WW, Chan DP, Cheung JL, Cheng AF. Department of Microbiology, The Chinese
University of Hong Kong, Prince of Wales Hospital, New Territories, Hong Kong SAR, China. J Clin Pathol.
2001 Jan;54(1):48-53.
BACKGROUND/AIM: Human papillomaviruses (HPVs) are important, but not sufficient, for the development of
cervical cancer. All three human beta-herpesviruses--cytomegalovirus (CMV) and human herpesviruses (HHV) types 6
and 7--have been detected in the cervix. In addition, CMV and HHV-6 can interact with HPVs in vivo. This study
examined the possible role of beta-herpesviruses in cervical cancer development.
METHODS: HPV, CMV, HHV-6, and HHV-7 were detected by the polymerase chain reaction using cervical scrapes
taken at colposcopy from 388 women. HPV types were identified using restriction fragment length polymorphisms.
Colposcopy guided biopsies were taken from abnormal areas, and the histological findings were regarded as the final
diagnoses. The associations between herpesvirus infection and the degree of cervical lesion were analysed with respect to
HPV status.
RESULTS: Of the 388 women, 51.8% had a normal cervix, 14.4% had cervical intraepithelial neoplasia grade 1 (CIN1),
8.2% had CIN2, 19.3% had CIN3, and 6.2% had invasive carcinoma. Overall, the positive rates for high, intermediate,
and low risk HPVs were 18.8%, 21.4%, and 5.2%, respectively. Fifteen patients harboured HPVs for which the genotype
could not be identified. Positive rates for CMV, HHV-6, and HHV-7 were 9.5%, 3.6%, and 3.4%, respectively. HPV
positive patients carried a higher risk for high grade lesions (CIN2/3 or carcinoma) (odds ratio (OR), 5.24; 95%
confidence interval (CI), 3.19 to 8.62; chi 2 = 51.79; p < 0.001), whereas those positive for CMV, HHV-6, or HHV-7 did
not. Thirteen of 131 patients with high grade lesions had HPV/herpesvirus coinfections, but no association with the
cervical lesion was noted. Furthermore, positive rates for herpesviruses among HPV negative, high/intermediate risk HPV
negative, and high risk HPV negative subgroups were similarly low and without a significant association.
CONCLUSIONS: The ubiquitous nature of herpesviruses may pose difficulty in elucidating their pathogenic role. These
results indicate that CMV,HHV-6, and HHV-7 are bystanders rather than cofactors in the oncogenesis of cervical cancer.
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