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[Cancer Research 61, 5202-5206, July 1, 2001]
© 2001 American Association for Cancer Research

Molecular Biology and Genetics

Molecular Mechanisms of Transcriptional Control of bcl-2 and c-myc in Follicular and Transformed Lymphoma1

Magdalena Arcinas, Caroline A. Heckman, John W. Mehew and Linda M. Boxer2

Center for Molecular Biology in Medicine, Palo Alto Veterans Affairs Medical Center and Department of Medicine, Stanford University School of Medicine, Stanford, California 94305


   ABSTRACT
Top
 ABSTRACT
INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
A synergistic interaction of Bcl-2 and c-Myc plays a role in lymphomagenesis in mice and in some patients as well. Progression of follicular lymphoma to a more aggressive lymphoma is seen in the majority of patients, and ~10% of the transformed lymphomas have a translocation of c-myc in addition to the translocation of bcl-2 found in the original follicular lymphoma. We investigated whether transcriptional deregulation of bcl-2 and c-myc could be examined in primary lymphoma cells by in vivo footprinting and in vitro protein-DNA binding studies. A matched pair of follicular and transformed lymphoma samples was examined. The transformed lymphoma had acquired a translocation of c-myc into the immunoglobulin heavy chain locus. High levels of bcl-2 expression were observed in both the follicular and transformed lymphomas, whereas the expression of c-myc was low in the follicular lymphoma and increased in the transformed lymphoma. In vivo footprint analysis revealed that a CRE site and a Cdx site in the bcl-2 promoter were occupied on the translocated alleles but not on the normal alleles in both the follicular and transformed lymphomas. Two nuclear factor {kappa}B sites were occupied on the translocated c-myc allele in the transformed lymphoma. Gel shift analysis revealed that these proteins bound to their respective sites in the bcl-2 or c-myc promoter. There was no evidence that the presence of one of the translocations in the immunoglobulin heavy chain locus influenced the expression of the other translocated gene.


   INTRODUCTION
Top
 ABSTRACT
 INTRODUCTION
MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 
The bcl-2 gene is translocated in the majority of cases of follicular lymphoma. The translocation of bcl-2 to the IgH3 gene locus leads to deregulated expression of bcl-2. High levels of bcl-2 mRNA are detected in lymphoma cells with the t(14;18) translocation (1 , 2) ; the transcripts originate from the translocated allele, whereas the normal allele is silent (3) . The mechanism of deregulation is not completely understood, but interactions of the IgH enhancers with the bcl-2 promoter are probably involved. The deregulated bcl-2 gene is thought to play a role in the development of follicular lymphoma. Constitutive overexpression of bcl-2 in the B cells of transgenic mice leads to a polyclonal expansion of B cells that display prolonged cell survival but no increase in cell cycling (4) . Progression to high-grade lymphoma is seen in these mice, and a translocation of the c-myc gene is observed in 50% of the high-grade lymphomas (4) .

Translocation of the c-myc gene to one of the immunoglobulin gene loci is seen in Burkitt’s lymphoma. Deregulated expression of the translocated c-myc gene is found in Burkitt’s lymphoma cells, and it is likely that the immunoglobulin enhancers play a role in the deregulated expression of c-myc.

Progression of follicular lymphoma to a more aggressive intermediate or high-grade lymphoma occurs in the majority of patients. The transformed lymphomas retain the t(14;18) translocation and usually acquire multiple, complex new chromosomal abnormalities. A new translocation of the c-myc gene into the immunoglobulin locus is observed in ~10% of the transformed lymphomas. Bcl-2 and c-Myc act synergistically in transgenic mice, as noted above (4, 5, 6) , and also in transfection studies (7) . Insight into the interaction of Bcl-2 and c-Myc comes from studies demonstrating that Bcl-2 prevents the apoptosis induced by c-Myc but does not interfere with its proliferative effect (8, 9, 10) .

We have studied the molecular mechanisms of deregulation of the bcl-2 and c-myc genes in follicular and Burkitt’s lymphoma, respectively. Our studies have identified two positive regulatory transcription factors, CREB and a Cdx/A-Myb complex, that activate the bcl-2 promoter in B cells (11 , 12) . Two NF-{kappa}B sites have been shown to be important for the regulation of both the human (13) and murine (14 , 15) c-myc promoters. We have also observed protection in vivo over a site for NM23H2 or a related transcription factor (16) .

It is not known whether the translocated c-myc gene in a transformed lymphoma is deregulated in a manner similar to that observed in Burkitt’s lymphoma. We also wished to determine whether the regulation of bcl-2 changed with transformation of the lymphoma or whether expression of bcl-2 was influenced by the presence of the c-myc translocation in the other IgH allele. Previous studies on the deregulation of bcl-2 and c-myc by translocation into the IgH gene have been performed on cell lines. It is important to demonstrate that similar mechanisms of deregulation occur in actual patient samples. We studied matched pairs of follicular and transformed lymphomas to examine the deregulation of the bcl-2 gene. One of the transformed lymphomas demonstrated a translocation of the c-myc gene into the IgH locus. We characterized the c-myc translocation and demonstrated that both bcl-2 and c-myc were expressed at high levels in the transformed lymphoma. Furthermore, we showed by in vivo footprinting and EMSA analysis that CREB and Cdx bind to the bcl-2 promoter and that NF-{kappa}B binds to the c-myc promoter.


   MATERIALS AND METHODS
Top
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
RESULTS
 DISCUSSION
 REFERENCES
 
DNA Probes.
pFL1 was used for bcl-2. The c-myc first exon probe was a PvuII-PvuII fragment, and the third exon probe was a ClaI-EcoRI fragment. The probes for the IgH gene included JH, Sµ, Cµ, and C{gamma}4.

Tumor Specimens.
Biopsy specimens from patients with lymphoma were obtained after informed consent using a protocol approved by the human subjects investigations review board. The specimens were stored as frozen viable single-cell suspensions as described previously (17) . B cells were purified by either positive selection with anti-CD19 or by negative selection. This case was diagnosed as follicular small cleaved cell lymphoma and progressed to a diffuse large cell lymphoma in 6 years. Biopsies from both time points were available for study.

Conventional Gel Electrophoresis.
DNA was extracted by standard techniques and digested with the indicated restriction enzymes. Electrophoresis was performed in 0.8% agarose gels.

Pulsed-Field Electrophoresis.
Cells were embedded in agarose plugs, lysed with detergent, and treated with proteinase K as described (18 , 19) . NotI digestion was performed, and the samples were separated on a 1% agarose gel in 0.5x Tris-borate-EDTA for 23 h at 160 V (5.5 V/cm) at room temperature with a pulse time of 55 s.

Preparation and Analysis of RNA.
Total cellular RNA was isolated by the guanidinium thiocyanate method, and 8 µg of RNA/sample were separated on 1.2% agarose-formaldehyde gels. The bcl-2 and c-myc probes are described above. Human GAPDH was used to control for variations in sample loading.

Ligation-mediated PCR.
In vivo footprinting by ligation-mediated PCR was performed as described previously (13 , 18 , 20) . The primers used for PCR were as described by Ji et al. (18) for the CRE site in the bcl-2 promoter and by Ji et al. (13) for the NF-{kappa}B sites in the c-myc gene. The guanine/adenine-specific cleavage of methylated DNA was performed as described by Strauss et al. (21) . The primers used for the Cdx site are shown below.

The coding primers were as follows:

5'-TTTCCCCCTTGGCATGAGATG-3'

5'-GATCTTTATTTCATGAGGCACGTTATAGTAAGT-3'

5'-TTCATGAGGCACGTTATAGTAAGTATTTTTAATATC-3'

The noncoding primers were as follows:

5'-GCATTCGAGTAAATTTAATTTCCAGGCAGC-3'

5-TTCCAGGCAGCTTAATACATTCTTTTTAGCC-3'

5'-GGCAGCTTAATACATTCTTTTTAGCCGTGTTAC-3'

EMSA.
The double-stranded oligonucleotides used for EMSA are shown below with the CRE, Cdx, and NF-{kappa}B sites in bold:

The oligonucleotides were synthesized with 5' overhangs and labeled with [{alpha}-32P]dCTP and Klenow polymerase. Binding conditions and electrophoresis were as described previously (11 , 13) .


   RESULTS
Top
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
DISCUSSION
 REFERENCES
 
Characterization of the bcl-2 and c-myc Translocations.
The original follicular lymphoma showed biallelic JH rearrangements, one of which comigrated with a bcl-2 rearrangement in the mbr region (Fig. 1A)Citation . No rearrangement of c-myc was seen. The transformed lymphoma showed the same bcl-2/JH rearrangement that was seen in the original follicular lymphoma. A new JH rearrangement that showed comigration with a c-myc rearrangement was seen in the transformed lymphoma (Fig. 1A)Citation . Comigration of the rearranged bands detected with JH, Cµ,and c-myc probes in BamHI digests demonstrated that the chromosome 14 breakpoint was upstream of the switch region. On the basis of these patterns of migration, we concluded that the c-myc gene rearranged into the JH region of a rearranged IgH allele in the original follicular lymphoma. Immunophenotypic analysis of the transformed lymphoma showed an absence of surface immunoglobulin, as would be expected with both IgH alleles involved in chromosomal rearrangements.



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  		Fig. 1. Characterization of the translocation breakpoints in the follicular and transformed lymphomas. A, Southern blot of follicular (F) and transformed (T) lymphomas with HindIII digestion. The blot was sequentially probed with sequences for bcl-2 (pFL1), IgH (JH), and c-myc (first exon). B, schematic representations of the t(14;18) and t(8;14) translocations (top and bottom, respectively). Filled boxes represent exons. UTR, untranslated region.

 
To map the location of the breakpoint in the c-myc gene, probes to the first and third exons were used with several different restriction enzyme digests. The breakpoint was located between the HindIII and PstI sites in the c-myc 5' flanking region. In HindIII digests, the same size rearranged c-myc band was seen with the first and third exon probes, but PstI digests showed no rearrangement. The bcl-2 and c-myc translocations are indicated schematically in Fig. 1BCitation .

Northern Analysis of the Follicular and Transformed Lymphomas.
bcl-2 mRNA was observed in both the follicular and transformed lymphomas at a similar level (Fig. 2A)Citation . Only a low level of c-myc mRNA was found in the follicular lymphoma. In the transformed lymphoma, c-myc expression was considerably higher (Fig. 2B)Citation . This is consistent with deregulation of c-myc expression associated with translocation into the IgH gene locus.



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  		Fig. 2. Northern analysis of the follicular (F) and transformed (T) lymphomas. The blot was sequentially probed with sequences for bcl-2 (pFL1; A), c-myc (exon III; B), and GAPDH (C) to control for variations in loading.

 
An in Vivo Footprint Is Located over the bcl-2 CRE Site on the Translocated Allele.
The translocated and normal bcl-2 alleles from the follicular and transformed lymphomas were separated by pulsed-field electrophoresis. In vivo footprint analysis by ligation-mediated PCR was performed on each one. With primer sets that cover the region surrounding the CRE site in the bcl-2 promoter region, a footprint was observed on the translocated allele but not on the normal bcl-2 allele (Fig. 3)Citation . This footprint was present in both the follicular and transformed lymphomas. Three guanine residues demonstrated protection on the coding strand, and one guanine was protected on the noncoding strand.



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  		Fig. 3. In vivo footprint over the CRE site in bcl-2 promoter in the follicular (F) and transformed (T) lymphomas. V, in vitro methylated DNA; Tl, translocated allele; N, normal bcl-2 allele. • indicate the protected guanines.

 
CREB Proteins in the Lymphoma Cells Bind to the bcl-2 CRE Site.
Small-scale nuclear extracts were prepared from the follicular and transformed lymphoma samples. EMSA with the bcl-2 CRE site revealed four specific bands of altered mobility (Fig. 4Citation , Lane 1). An excess of cold bcl-2 CRE oligonucleotide or a consensus CRE oligonucleotide prevented formation of all four complexes (Fig. 4Citation , Lanes 2 and 3). The three slowest migrating bands were supershifted with an antibody that recognizes all CREB family members (Fig. 4Citation , Lane 5), whereas the addition of preimmune serum had no effect (Fig. 4Citation , Lane 4).



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  		Fig. 4. EMSA of the bcl-2 CRE site with nuclear extracts from the follicular (F) and transformed (T) lymphomas. Lane 1 contains no competitor oligonucleotide; Lanes 2 and 3 contain a 50-fold molar excess of cold bcl-2 CRE site oligonucleotide (self) and cold consensus CRE site oligonucleotide (cons), respectively; Lane 4 contains preimmune serum (PI); Lane 5 contains an antibody that recognizes all CREB family members. The filled arrows (left) indicate the four specific complexes, and the open arrows (right) indicate the supershifted complexes. Although not shown, all combinations were run with nuclear extracts from both follicular and transformed lymphoma cells, and no differences were observed between the nuclear extracts.

 
The Cdx Site Is Protected on the Translocated bcl-2 Allele.
Because the Cdx binding site is an AT-rich site, we used a modification of the in vivo footprinting procedure that permits the analysis of both guanine and adenine residues (21) . In vivo footprinting with a primer set that covered the Cdx site revealed protection of this site on the translocated allele in both the follicular and transformed lymphomas (Fig. 5)Citation . No protection was observed over the Cdx site on the untranslocated bcl-2 allele.



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  		Fig. 5. In vivo footprint analysis of adenines and guanines at the Cdx site in bcl-2 promoter in the follicular (F) and transformed (T) lymphomas. V, in vitro methylated DNA; Tl, translocated allele; N, normal bcl-2 allele. • indicate protected guanines and adenines.

 
Specific Protein Complexes Are Observed with the Cdx Binding Site and Nuclear Extracts from Lymphoma Cells.
EMSA with nuclear extracts from both the follicular and transformed lymphoma samples with the Cdx binding site revealed two specific protein complexes (Fig. 6)Citation . Competition with an excess of the wild-type sequence was observed (Fig. 6Citation , Lanes 2 and 5), whereas a sequence with a mutated Cdx site showed no competition (Fig. 6Citation , Lanes 3 and 6). There was no obvious difference in the complexes formed with the follicular or transformed lymphoma samples. We have shown previously that both Cdx and A-Myb are present in the protein complex that forms at the Cdx site in the bcl-2 promoter (11) .



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  		Fig. 6. EMSA of the bcl-2 Cdx site with nuclear extracts from follicular (F) and transformed (T) lymphoma cells. Lanes 1 and 4, no competitor DNA; Lanes 2 and 5, 100-fold molar excess of cold wild-type competitor (self); Lanes 3 and 6, 100-fold molar excess of the mutated Cdx site (mut).

 
In Vivo Footprints Are Located over the Two NF-{kappa}B Sites on the Translocated c-myc Allele.
The translocated and normal c-myc alleles from the transformed lymphoma were separated by electrophoresis, and ligation-mediated PCR was performed on each one. A protected region was observed on the translocated c-myc allele, but not on the normal c-myc allele. This region corresponded to the NF-{kappa}B site in the 5' flanking region. Three guanine residues were protected on the coding strand, and two guanines were protected on the noncoding strand (Fig. 7A)Citation .



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  		Fig. 7. In vivo footprint analysis of the c-myc promoter. A, footprint analysis of the c-myc 5' flanking NF-{kappa}B site in transformed lymphoma cells. The lanes are labeled as in Fig. 3Citation . B, in vivo footprint analysis of the c-myc exon NF-{kappa}B site in transformed lymphoma cells. The lanes are labeled as in Fig. 3Citation .

 
With primer sets that cover a region of exon I of c-myc, we observed a footprint over the exon NF-{kappa}B site on the translocated c-myc allele. Three guanines were protected on the coding strand, and two guanine residues showed protection on the noncoding strand (Fig. 7B)Citation . The region surrounding the NM23H2 site was examined by ligation-mediated PCR, but no footprint at this site was observed on either the normal or the translocated c-myc allele. No clear footprints were observed in these regions of the c-myc gene in the follicular lymphoma.

NF-{kappa}B Proteins Present in the Lymphoma Cells Bind to the c-myc NF-{kappa}B Sites.
EMSA was performed with oligonucleotides that encompassed the 5' flanking and the exon NF-{kappa}B sites. The results with the exon NF-{kappa}B site oligonucleotide are shown in Fig. 8Citation , and the results with the 5' flanking probe were similar. Although no binding of NF-{kappa}B to the 5' flanking or exon NF-{kappa}B sites in the follicular lymphoma could be demonstrated by in vivo footprint analysis, NF-{kappa}B proteins are present in nuclear extracts from the follicular lymphoma. One intense complex was observed with the NF-{kappa}B site, and faint complexes of slower and faster mobility could be seen as well (Fig. 8Citation , Lanes 1 and 2). An antibody against p50 supershifted all of the complexes, although the intense complex was not completely shifted (Fig. 8Citation , Lane 3). Excess cold consensus NF-{kappa}B and exon NF-{kappa}B oligonucleotides prevented complex formation (Fig. 8Citation , Lanes 4 and 5). The c-myc 5' flanking NF-{kappa}B oligonucleotide also prevented complex formation when it was present in excess (data not shown).



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  		Fig. 8. EMSA of the exon NF-{kappa}B site with nuclear extracts from the follicular (F) and transformed (T) lymphomas. Lane 1, no addition; Lane 2, preimmune serum; Lane 3, antibody against p50; Lanes 4 and 5, 50-fold molar excess of cold consensus NF-{kappa}B site (cons) and cold exon NF-{kappa}B site (self), respectively. Similar results were obtained with the c-myc 5' flanking region NF-{kappa}B site oligonucleotide. No differences were observed between the nuclear extracts from the follicular and transformed lymphoma cells.

 

   DISCUSSION
Top
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
REFERENCES
 
The synergistic effects of Bcl-2 and c-Myc are well established in mouse models of B-cell malignancies. We investigated the deregulation of the bcl-2 and c-myc genes in a matched pair of follicular and transformed lymphoma cells. Both lymphomas showed the t(14;18) translocation that is characteristic of follicular lymphoma. In the follicular lymphoma, the other IgH allele had undergone a productive rearrangement, and surface expression of IgM was observed. The transformed lymphoma showed a new rearrangement of this IgH allele that involved the c-myc locus. The translocation occurred in the JH region of the functionally rearranged allele. No surface immunoglobulin was detected on the transformed lymphoma cells. There have been other reports of translocation of the c-myc gene into a productively rearranged immunoglobulin gene (22 , 23) , and replacement of a rearranged VH region with another one has also been reported (24 , 25) . It is possible that recombinase enzymes were involved in the translocation. Rag1 and Rag2 are reexpressed in normal germinal center B cells, and receptor revision is seen in this population of lymphocytes (26, 27, 28) . The breakpoint in the c-myc gene in the transformed lymphoma occurred in the 5' flanking region. Increased expression of c-myc mRNA was observed in the transformed lymphoma compared with the follicular lymphoma.

We previously have shown that the CRE site in the bcl-2 promoter is occupied on the translocated allele in the DHL-4 cell line and that this site is a positive regulatory element (12 , 18) . The CRE site was occupied on the translocated bcl-2 gene in the primary follicular and transformed lymphoma cells. This finding suggests that the CRE site plays a role in the regulation of bcl-2 expression in primary lymphoma cells that have not been adapted to growth in tissue culture. We also showed that CREB proteins were present in the nuclear extracts of both the follicular and transformed lymphomas and that they bound to the bcl-2 promoter CRE site. A-Myb and Cdx cooperate to increase bcl-2 promoter activity in B cells (11) . Because the Cdx site contains only a single guanine, with the standard methylation protection assay we have not previously observed in vivo protection of this site. Occupation of the Cdx site on the translocated bcl-2 allele was observed in both the follicular and transformed lymphoma cells with a modification of the in vivo footprinting procedure that allows analysis of both guanine and adenine residues. Our studies suggest that both CREB and the Cdx/A-Myb complex are important for regulation of the translocated bcl-2 allele in primary lymphoma cells.

In Burkitt’s cell lines, we have shown that two NF-{kappa}B sites and a binding site for NM23 or a related transcription factor are occupied on the translocated c-myc allele but not on the normal allele (13 , 16) . It is important to examine the regulation of the c-myc gene in primary cells because it is possible that this gene product plays a role in adaptation of cells to growth in tissue culture. No clear footprints were observed over these sites in the c-myc promoter in the follicular lymphoma cells. This may reflect the fact that c-myc expression is very low in these cells. We did observe footprints over both NF-{kappa}B sites on the translocated c-myc allele in the transformed lymphoma cells. There was no footprint over the NM23 site in these cells. It is possible that this reflects a difference in the regulation of c-myc expression in the primary lymphoma cells compared with the Burkitt’s lymphoma cell lines. It is also possible that the activity of two NF-{kappa}B sites is sufficient for expression of c-myc. In the Burkitt’s cell lines that we studied previously, only one NF-{kappa}B site was present on the translocated c-myc allele. In the Raji cell line, the exon NF-{kappa}B site was deleted, whereas the 5' flanking NF-{kappa}B site was removed by the translocation in the Ramos cell line.

The bcl-2 gene was expressed at high levels in both the follicular and transformed lymphomas. It appears that translocation of the c-myc gene into the other IgH locus has no effect on the expression of the translocated bcl-2 gene. Deregulation of bcl-2 and c-myc expression by translocation is thought to be attributable to the influence of the IgH enhancers and interactions of these elements with the bcl-2 and c-myc promoters. We have preliminary evidence that overlapping, but not identical, elements of the IgH enhancers are required for deregulation of the bcl-2 and c-myc genes. The regulatory elements in the enhancers that deregulate c-myc or bcl-2 also differ somewhat from those that control expression of the normal IgH gene (29) .4

From these studies we can conclude that the deregulation of the bcl-2 gene in the t(14;18) translocation is similar in follicular and transformed lymphomas. A similar pattern of deregulation of c-myc expression was observed in the transformed lymphoma and in Burkitt’s cell lines. We did not find any evidence to suggest that the presence of one translocation had any effect on expression of the gene involved in the other translocation. Primary lymphoma samples can be used to study the regulation of the translocated bcl-2 and c-myc genes, and the mechanism of deregulation of each promoter appears to be similar to that observed in established cell lines.


   FOOTNOTES
 
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked advertisement in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

1 Supported by NIH Grants CA69322 and CA56764. Back

2 To whom requests for reprints should be addressed, at Division of Hematology, S-161, Stanford University School of Medicine, Stanford, CA 94305-5112. Phone: (650) 849-0551; Fax: (650) 858-3982; E-mail: lboxer{at}stanford.edu Back

3 The abbreviations used are: IgH, immunoglobulin heavy chain; CREB, cAMP-responsive element binding protein; NF-{kappa}B, nuclear factor {kappa}B; EMSA, electrophoretic mobility shift assay; CRE, cAMP-responsive element; GAPDH, glyceraldehyde-3-phosphate dehydrogenase. Back

4 Unpublished data. Back

Received 2/ 6/01. Accepted 5/ 1/01.


   REFERENCES
Top
 ABSTRACT
 INTRODUCTION
 MATERIALS AND METHODS
 RESULTS
 DISCUSSION
 REFERENCES
 

  1. Cleary M. L., Smith S. D., Sklar J. Cloning and structural analysis of cDNAs for bcl-2 and a hybrid bcl-2/Immunoglobulin transcript resulting from the t(14;18) translocation. Cell, 47: 19-28, 1986.[Medline]
  2. Graninger W. B., Seto M., Boutain B., Goldman P., Korsmeyer S. J. Expression of bcl-2 and bcl-2-Ig fusion transcripts in normal and neoplastic cells. J. Clin. Invest., 80: 1512-1515, 1987.
  3. Seto M., Jaeger U., Hockett R. D., Graninger W., Bennett S., Goldman P., Korsmeyer S. J. Alternative promoters and exons, somatic mutation and deregulation of the Bcl-2-Ig fusion gene in lymphoma. EMBO J., 7: 123-131, 1988.[Medline]
  4. McDonnell T. J., Korsmeyer S. J. Progression from lymphoid hyperplasia to high grade malignant lymphoma in mice transgenic for the t(14;18). Nature (Lond.), 349: 254-256, 1991.[Medline]
  5. Strasser A., Harris A. W., Bath M. L., Cory S. Novel primitive lymphoid tumors induced in transgenic mice by cooperation between myc and bcl-2. Nature (Lond.), 348: 331-333, 1990.[Medline]
  6. Cory S., Vaux D. L., Strasser A., Harris A. W., Adams J. M. Insights from Bcl-2 and Myc: malignancy involves abrogation of apoptosis as well as sustained proliferation. Cancer Res., 59: 1685s-1692s, 1999.
  7. Vaux D. L., Cory S., Adams J. M. Bcl-2 gene promotes haemopoietic cell survival and cooperates with c-myc to immortalize pre-B cells. Nature (Lond.), 335: 440-442, 1988.[Medline]
  8. Bissonnette R. P., Echeverri F., Mahboubi A., Green D. R. Apoptotic cell death induced by c-myc is inhibited by bcl-2. Nature (Lond.), 359: 552-554, 1992.[Medline]
  9. Fanidi A., Harrington E. A., Evan G. I. Cooperative interaction between c-myc and bcl-2 proto-oncogenes. Nature (Lond.), 359: 554-556, 1992.[Medline]
  10. Wagner A. J., Small M. B., Hay N. Myc-mediated apoptosis is blocked by ectopic expression of bcl-2. Mol. Cell. Biol., 13: 2432-2440, 1993.[Abstract/Free Full Text]
  11. Heckman C. A., Mehew J. W., Ying G-G., Introna M., Golay J., Boxer L. M. A-Myb up-regulates bcl-2 through a Cdx binding site in t(14;18) lymphoma cells. J. Biol. Chem., 275: 6499-6508, 2000.[Abstract/Free Full Text]
  12. Wilson B. E., Mochon E., Boxer L. M. Induction of bcl-2 expression by phosphorylated CREB proteins during B-cell activation and rescue from apoptosis. Mol. Cell. Biol., 16: 5546-5556, 1996.[Abstract]
  13. Ji L., Arcinas M., Boxer L. M. NF-{kappa}B sites function as positive regulators of expression of the translocated c-myc allele in Burkitt’s lymphoma. Mol. Cell. Biol., 14: 7967-7974, 1994.[Abstract/Free Full Text]
  14. Kessler D. J., Spicer D. B., La Rosa F. A., Sonenshein G. A novel NF-{kappa}B element within exon 1 of the murine c-myc gene. Oncogene, 7: 2447-2453, 1992.[Medline]
  15. La Rosa F. A., Pierce J. W., Sonenshein G. E. Differential regulation of the c-myc oncogene promoter by the NF-{kappa}B rel family of transcription factors. Mol. Cell. Biol., 14: 1039-1044, 1994.[Abstract/Free Full Text]
  16. Ji L., Arcinas M., Boxer L. M. The transcription factor, Nm23H2, binds to and activates the translocated c-myc allele in Burkitt’s lymphoma. J. Biol. Chem., 270: 13392-13398, 1995.[Abstract/Free Full Text]
  17. Meeker T., Lowder J., Maloney D. G., Miller R., Thielemans K., Warnke R., Levy R. A clinical trial of anti-idiotype therapy for B cell malignancy. Blood, 65: 1349-1354, 1985.[Abstract/Free Full Text]
  18. Ji L., Mochon E., Arcinas M., Boxer L. M. CREB proteins function as positive regulators of the translocated bcl-2 allele in t(14;18) lymphomas. J. Biol. Chem., 271: 22687-22691, 1996.[Abstract/Free Full Text]
  19. Zelenetz A., Chu G., Galili N., Bangs C. D., Horning S. J., Donton T. A., Cleary M. L., Levy R. Enhanced detection of the t(14;18) translocation in malignant lymphoma using pulsed-field gel electrophoresis. Blood, 78: 1552-1560, 1991.[Abstract/Free Full Text]
  20. Mueller P. R., Wold B. In vivo footprinting of a muscle specific enhancer by ligation-mediated PCR. Science (Wash. DC), 246: 780-786, 1989.[Abstract/Free Full Text]
  21. Strauss E. C., Andrews N. C., Higgs D. R., Orkin S. H. In vivo footprinting of the human {alpha}-globin locus upstream regulatory element by guanine and adenine ligation-mediated polymerase chain reaction. Mol. Cell. Biol., 12: 2135-2142, 1992.[Abstract/Free Full Text]
  22. Lambrechts A. C., Dorssers L. C. J., Hupkes P. E., van Gurp R., Baumgarten R., Hagemeijer A., van’t Veer M. B., Touw I. P. Genomic organization of the translocations (8;14) and (14;18) in a new lymphoma cell line. Leukemia, 8: 1164-1171, 1994.[Medline]
  23. Yano T., Jaffe E. S., Longo D. L., Raffeld M. MYC rearrangements in histologically progressed follicular lymphomas. Blood, 80: 758-767, 1992.[Abstract/Free Full Text]
  24. Kleinfield R., Hardy R. R., Tarlinton D., Dangl J., Herzenberg L. A., Weigert M. Recombination between an expressed immunoglobulin heavy-chain gene and a germline variable gene segment in a Ly1+ B-cell lymphoma. Nature (Lond.), 322: 843-846, 1986.[Medline]
  25. Reth M., Gehrmann P., Petrac E., Wiese P. A novel VH to VHDJH joining mechanism in heavy-chain- negative (null) pre-B cells results in heavy-chain production. Nature (Lond.), 322: 840-842, 1986.[Medline]
  26. Han S., Dillon S. R., Zheng B., Shimoda M., Schlissel M. S., Kelsoe G. V(D)J recombinase activity in a subset of germinal center B lymphocytes. Science (Wash. DC), 278: 301-305, 1997.[Abstract/Free Full Text]
  27. Hikida M., Ohmori H. Rearrangement of {lambda} light chain genes in mature B cells in vitro and in vivo. Function of reexpressed recombination-activating gene (RAG) products. J. Exp. Med., 187: 795-799, 1998.[Abstract/Free Full Text]
  28. Papavasiliou F., Casellas R., Suh H., Qin X. F., Besemer E., Pelanda R., Nemazee D., Rajewsky K., Nussenzweig M. C. V(D)J recombination in mature B cells: a mechanism for altering antibody responses. Science (Wash. DC), 278: 298-301, 1997.[Abstract/Free Full Text]
  29. Kanda K., Hu H-M., Zhang L., Grandchamps J., Boxer L. M. NF-{kappa}B activity is required for the deregulation of c-myc expression by the immunoglobulin heavy chain enhancer. J. Biol. Chem., 275: 32338-32346, 2000.[Abstract/Free Full Text]



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