Analysis of VH genes used by neoplastic B cells in endemic Burkitt's lymphoma shows somatic hypermutation and intraclonal heterogeneity

Tumor cell lines from six typical cases of endemic Epstein-Barr virus (EBV) genome-positive Burkitt's lymphoma (BL) have been investigated for usage and mutational pattern of Ig VH genes. The neoplastic cells all had a t(8;14) (q24;q32) translocation involving the c-myc protooncogene. The VH genes were derived from VH1, VH3 and VH4, and both the IgM-positive (four cases) and IgG-positive (two cases) were extensively mutated from germline sequence. In two cases, early and late passage tumor cells were available, and the VH nucleotide sequences were identical, indicating that mutations had not accumulated in vitro. In a further case, there was evidence of sequence heterogeneity, which appeared to have been generated in vivo, indicating that the tumor cell VH gene was able to undergo posttranslocation somatic hypermutation. Analysis of the relatively nonpolymorphic VH4 genes for the pattern of replacement or silent mutations did not show a role for antigen selection in the expressed sequences.

Download Full-text

VH and VL gene analysis in sporadic Burkitt's lymphoma shows somatic hypermutation, intraclonal heterogeneity, and a role for antigen selection

Blood ◽

10.1182/blood.v88.9.3562.bloodjournal8893562 ◽

1996 ◽

Vol 88 (9) ◽

pp. 3562-3568 ◽

Cited By ~ 69

Author(s):

CJ Chapman ◽

JX Zhou ◽

C Gregory ◽

AB Rickinson ◽

FK Stevenson

Keyword(s):

Tumor Cell ◽

Somatic Hypermutation ◽

Variable Region ◽

Burkitt’S Lymphoma ◽

Burkitt's Lymphoma ◽

Biopsy Material ◽

Tumor Biopsy ◽

Barr Virus ◽

Mutational Pattern ◽

Epstein Barr

Tumor cell lines and one tumor biopsy from seven cases of Epstein-Barr virus (EBV) genome-negative sporadic Burkitt's lymphoma (BL) have been investigated for usage and mutational pattern of Ig variable region genes. The VH genes were derived from the VH 3 (one) and VH4 (six) families and both the IgM-positive (six) and the IgA-positive (one) were all mutated from their germline counterparts. The VL genes were derived from V kappa 1 (one), V kappa 3 (one), V lambda 1 (four), and V lambda 2 (one) families and were also somatically hypermutated. Biopsy material from one of the IgM-positive cases showed VH and VL sequences that matched the derived cell line, with additional intraclonal sequence heterogeneity, indicating that the tumor cells had undergone posttranformation somatic mutation. Mutational patterns in V(H) genes did not show a conventional role for antigen in selecting tumor cell sequences. In contrast, patterns in VL sequences were consistent with a role for antigen in five of seven cases. The pattern of extensive scattered somatic hypermutation and intraclonal variation is similar to that in VH sequences of EBV genome-positive endemic BL, although the degree of mutational activity is less. These common features indicate that B cells involved in the two variants of BL may share a common clonal history.

Download Full-text

Epstein-Barr virus (EBV)-associated lymphoproliferative disease in the SCID mouse model: implications for the pathogenesis of EBV-positive lymphomas in man.

Journal of Experimental Medicine ◽

10.1084/jem.173.1.147 ◽

1991 ◽

Vol 173 (1) ◽

pp. 147-158 ◽

Cited By ~ 191

Author(s):

M Rowe ◽

L S Young ◽

J Crocker ◽

H Stokes ◽

S Henderson ◽

...

Keyword(s):

B Cells ◽

B Cell ◽

Epstein Barr Virus ◽

Large Cell ◽

Burkitt’S Lymphoma ◽

Scid Mice ◽

Burkitt's Lymphoma ◽

Barr Virus ◽

Epstein Barr

When human peripheral blood lymphocytes (PBLs) from Epstein-Barr virus (EBV)-seropositive donors are injected intraperitoneally into SCID mice, EBV+ B cell tumors develop within weeks. A preliminary report (Mosier, D. E., R. J. Gulizia, S. M. Baird, D. D. Richman, D. B. Wilson, R. I. Fox, and T. J. Kipps, 1989. Blood. 74(Suppl. 1):52a) has suggested that such tumors resemble the EBV-positive malignancy, Burkitt's lymphoma. The present work shows that generally the human (hu) PBL-SCID tumors are distinct from Burkitt's lymphoma and instead resemble lymphoblastoid cell lines (LCLs) generated by EBV-infection of normal B cells in vitro in terms of: (a) their cell surface phenotype, with expression of B cell activation antigens and adhesion molecules, (b) normal karyotype, and (c) viral phenotype, with expression of all the transformation-associated EBV latent proteins and, in a minority of cells, productive cycle antigens. Indeed, in vitro-transformed LCLs also grow when inoculated into SCID mice, the frequency of tumor outgrowth correlating with the in vitro growth phenotype of the LCL which is itself determined by the identity of the transforming virus (i.e., type 1 or type 2 EBV). Histologically the PBL-derived hu-SCID tumors resemble the EBV+ large cell lymphomas that develop in immuno-suppressed patients and, like the human tumors, often present at multiple sites as individual monoclonal or oligoclonal foci. The remarkable efficiency of tumor development in the hu-SCID model suggests that lymphomagenesis involves direct outgrowth of EBV-transformed B cells without requirement for secondary genetic changes, and that selection on the basis of cell growth rate alone is sufficient to explain the monoclonal/oligoclonal nature of tumor foci. EBV+ large cell lymphoma of the immunosuppressed may arise in a similar way.

Download Full-text

Epstein-Barr Virus and the Somatic Hypermutation of Immunoglobulin Genes in Burkitt's Lymphoma Cells

Journal of Virology ◽

10.1128/jvi.75.21.10488-10492.2001 ◽

2001 ◽

Vol 75 (21) ◽

pp. 10488-10492 ◽

Cited By ~ 26

Author(s):

Reuben S. Harris ◽

Debbie S. G. Croom-Carter ◽

Alan B. Rickinson ◽

Michael S. Neuberger

Keyword(s):

Germinal Center ◽

Epstein Barr Virus ◽

Somatic Hypermutation ◽

Burkitt’S Lymphoma ◽

Burkitt's Lymphoma ◽

Gene Products ◽

Germinal Center Reaction ◽

Barr Virus ◽

Antibody Maturation ◽

Epstein Barr

ABSTRACT It has been suggested that Epstein-Barr virus (EBV) might suppress antibody maturation either by facilitating bypass of the germinal center reaction or by inhibiting hypermutation directly. However, by infecting the Burkitt's lymphoma (BL) cell line Ramos, which hypermutates constitutively and can be considered a transformed analogue of a germinal center B cell, with EBV as well as by transfecting it with selected EBV latency genes, we demonstrate that expression of EBV gene products does not lead to an inhibition of hypermutation. Moreover, we have identified two natural EBV-positive BL cell lines (ELI-BL and BL16) that hypermutate constitutively. Thus, contrary to expectations, EBV gene products do not appear to affect somatic hypermutation.

Download Full-text

Burkitt's lymphoma: differential killing of Epstein-Barr virus (EBV) (+) and EBV(-) Burkitt lymphoma cells in vitro and dose-dependent lytic induction by bortezomib in vivo

Infectious Agents and Cancer ◽

10.1186/1750-9378-4-s2-p16 ◽

2009 ◽

Vol 4 (S2) ◽

Author(s):

AL Dufresne ◽

D Fu ◽

RF Ambinder

Keyword(s):

Burkitt Lymphoma ◽

Epstein Barr Virus ◽

Burkitt’S Lymphoma ◽

Lymphoma Cells ◽

Barr Virus ◽

Epstein Barr ◽

Differential Killing ◽

Dose Dependent

Download Full-text

Epstein-Barr Virus Contributes to the Malignant Phenotype and to Apoptosis Resistance in Burkitt’s Lymphoma Cell Line Akata

Journal of Virology ◽

10.1128/jvi.72.11.9150-9156.1998 ◽

1998 ◽

Vol 72 (11) ◽

pp. 9150-9156 ◽

Cited By ~ 104

Author(s):

Jun Komano ◽

Makoto Sugiura ◽

Kenzo Takada

Keyword(s):

Epstein Barr Virus ◽

Burkitt’S Lymphoma ◽

Soft Agar ◽

Burkitt's Lymphoma ◽

Nuclear Antigen ◽

Apoptosis Resistance ◽

Barr Virus ◽

Ebv Infection ◽

Epstein Barr

ABSTRACT In the present study, we established an in vitro system representing the Burkitt’s lymphoma (BL)-type Epstein-Barr virus (EBV) infection which is characterized by expression of EBV-determined nuclear antigen 1 (EBNA-1) and absence of EBNA-2 and latent membrane protein 1 (LMP1) expression. EBV-negative cell clones isolated from the EBV-positive BL line Akata were infected with an EBV recombinant carrying a selectable marker, and the following selection culture easily yielded EBV-infected clones. EBV-reinfected clones showed BL-type EBV expression and restored the capacity for growth on soft agar and tumorigenicity in SCID mice that were originally retained in parental EBV-positive Akata cells and lost in EBV-negative subclones. Moreover, it was found that EBV-positive cells were more resistant to apoptosis than were EBV-negative cells. EBV-infected cells expressed the bcl-2 protein, through which cells might become resistant to apoptosis, at a higher level than did uninfected cells. This is the first report that BL-type EBV infection confers apoptosis resistance even in the absence of expression of LMP1 and BHRF1, both of which are known to have an antiapoptotic function. Surprisingly, transfection of the EBNA-1 gene into EBV-negative Akata clones could not restore malignant phenotypes and apoptosis resistance, thus suggesting that EBNA-1 alone was not sufficient for conferring them. Our results suggest that the persistence of EBV in BL cells is required for the cells to be more malignant and apoptosis resistant, which underlines the oncogenic role of EBV in BL genesis.

Download Full-text

Demonstration of the Burkitt's lymphoma Epstein-Barr virus phenotype in dividing latently infected memory cells in vivo

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2237267100 ◽

2003 ◽

Vol 101 (1) ◽

pp. 239-244 ◽

Cited By ~ 177

Author(s):

D. Hochberg ◽

J. M. Middeldorp ◽

M. Catalina ◽

J. L. Sullivan ◽

K. Luzuriaga ◽

...

Keyword(s):

Epstein Barr Virus ◽

Burkitt’S Lymphoma ◽

Burkitt's Lymphoma ◽

Memory Cells ◽

Barr Virus ◽

Latently Infected ◽

Epstein Barr

Download Full-text

Heterogeneous expression of Epstein-Barr virus latent proteins in endemic Burkitt's lymphoma

Blood ◽

10.1182/blood.v86.2.659.bloodjournal862659 ◽

1995 ◽

Vol 86 (2) ◽

pp. 659-665 ◽

Cited By ~ 85

Author(s):

G Niedobitek ◽

A Agathanggelou ◽

M Rowe ◽

EL Jones ◽

DB Jones ◽

...

Keyword(s):

Tumor Cells ◽

Cell Lines ◽

Epstein Barr Virus ◽

Burkitt’S Lymphoma ◽

Operational Definition ◽

Lytic Cycle ◽

Burkitt's Lymphoma ◽

Barr Virus ◽

Epstein Barr

Epstein-Barr virus (EBV)-infected cells may sustain three distinct forms of virus latency. In lymphoblastoid cell lines, six EBV-encoded nuclear antigens (EBNA1, 2, 3A, 3B, 3C, -LP), three latent membrane proteins (LMP1, 2A, 2B), and two nuclear RNAs (EBERs) are expressed. This form of latency, termed latency III, is also encountered in some posttransplant lymphoproliferative disorders. In EBV-positive cases of Hodgkin's disease, the EBERs, EBNA1, and the LMPs are expressed (latency II), whereas in Burkitt's lymphoma (BL) only the EBERs and EBNA1 have been detected (latency I). We have studied the expression of EBV proteins in 17 cases of EBV-positive endemic BL by immunohistology. Expression of LMP1 was seen in variable proportions of tumor cells in two cases and EBNA2 was detected in some tumor cells in three other cases. Also, the BZLF1 trans-activator protein was expressed in a few tumor cells in 6 cases, indicating entry into the lytic cycle. A phenotypic drift from latency I to latency III has been observed previously in some BL cell lines. Our results suggest that a similar phenomenon may occur in BL in vivo and indicate that the operational definition of EBV latencies is not easily applied to human tumors.

Download Full-text

Epstein-Barr Virus Nuclear Antigen 1 Sequences in Endemic and Sporadic Burkitt’s Lymphoma Reflect Virus Strains Prevalent in Different Geographic Areas

Journal of Virology ◽

10.1128/jvi.73.2.965-975.1999 ◽

1999 ◽

Vol 73 (2) ◽

pp. 965-975 ◽

Cited By ~ 65

Author(s):

G. Habeshaw ◽

Q. Y. Yao ◽

A. I. Bell ◽

D. Morton ◽

A. B. Rickinson

Keyword(s):

Epstein Barr Virus ◽

De Novo ◽

Burkitt’S Lymphoma ◽

Virus Genome ◽

Burkitt's Lymphoma ◽

Nuclear Antigen ◽

Barr Virus ◽

Epstein Barr ◽

Virus Strains

ABSTRACT The Epstein-Barr virus (EBV) nuclear antigen EBNA1 is the only viral protein detectably expressed in virus genome-positive Burkitt’s lymphoma (BL); recent work has suggested that viral strains with particular EBNA1 sequence changes are preferentially associated with this tumor and that, within a patient, the tumor-associated variant may have arisen de novo as a rare mutant of the dominant preexisting EBV strain (K. Bhatia, A. Raj, M. J. Gutierrez, J. G. Judde, G. Spangler, H. Venkatesh, and I. T. Magrath, Oncogene 13:177–181, 1996). In the present work we first study 12 BL patients and show that the virus strain in the tumor is identical in EBNA1 sequence and that it is matched at several other polymorphic loci to the dominant strain rescued in vitro from the patient’s normal circulating B cells. We then analyze BL-associated virus strains from three different geographic areas (East Africa, Europe, and New Guinea) alongside virus isolates from geographically matched control donors by using sequence changes in two separate regions of the EBNA1 gene (N-terminal codons 1 to 60 and C-terminal codons 460 to 510) to identify the EBNA1 subtype of each virus. Different geographic areas displayed different spectra of EBNA1 subtypes, with only limited overlap between them; even type 2 virus strains, which tended to be more homogeneous than their type 1 counterparts, showed geographic differences at the EBNA1 locus. Most importantly, within any one area the EBNA1 subtypes associated with BL were also found to be prevalent in the general population. We therefore find no evidence that Burkitt lymphomagenesis involves a selection for EBV strains with particular EBNA1 sequence changes.

Download Full-text