scholarly journals The correlation of breakpoint cluster region rearrangement and p210 phl/abl expression with morphological analysis of Ph-negative chronic myeloid leukemia and other myeloproliferative diseases

Blood ◽  
1988 ◽  
Vol 71 (2) ◽  
pp. 349-355
Author(s):  
LM Wiedemann ◽  
KK Karhi ◽  
MK Shivji ◽  
SI Rayter ◽  
SM Pegram ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Protein Tyrosine Kinase ◽  
Blood Film ◽  
Chromosome 22 ◽  
Molecular Alteration ◽  
Breakpoint Cluster Region ◽  
Cluster Region ◽  
Ph Chromosome ◽  
Atypical Cml

The chromosome 22 derivative, the Philadelphia (Ph) chromosome, results from a reciprocal translocation t(9;22) (q34;q11) and is associated with chronic myeloid leukemia (CML). The translocation can be identified at the DNA level in Ph-positive CML by using a probe to the breakpoint cluster region (bcr). In addition, as a result of this translocation an abl-related 210-kd protein with protein tyrosine kinase (PTK) activity is produced. We analyzed 28 cases of Ph-negative CML for rearrangement of the chromosome 22 sequences and found that eight of the 28 show rearrangement of the bcr. When 12 of the Ph- negative cases were independently reviewed, five were indistinguishable from Ph-positive CML on the basis of morphology, peripheral blood film and clinical details. These five also showed bcr rearrangement. The other seven were reclassified as six atypical CML (aCML) and one chronic myelomonocytic leukemia (CMML). None of these seven showed bcr rearrangement. In addition 11 cases of bcr- CML were assayed for abl- related PTK, and no detectable activity was present, whereas p210 phl/abl PTK was observed both in Ph-positive (three cases examined) and Ph-negative, bcr + (four cases examined) CML. Therefore, bcr + CML, whether or not the Ph chromosome is cytogenetically apparent, involves a similar molecular alteration and produces the 210-kd protein with enhanced PTK activity. Furthermore, these cases can be distinguished from Ph-negative bcr- CML by careful evaluation of clinical and hematologic data.

scholarly journals The correlation of breakpoint cluster region rearrangement and p210 phl/abl expression with morphological analysis of Ph-negative chronic myeloid leukemia and other myeloproliferative diseases

Blood ◽  
1988 ◽  
Vol 71 (2) ◽  
pp. 349-355 ◽  
Author(s):  
LM Wiedemann ◽  
KK Karhi ◽  
MK Shivji ◽  
SI Rayter ◽  
SM Pegram ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Protein Tyrosine Kinase ◽  
Blood Film ◽  
Chromosome 22 ◽  
Molecular Alteration ◽  
Breakpoint Cluster Region ◽  
Cluster Region ◽  
Ph Chromosome ◽  
Atypical Cml

Abstract The chromosome 22 derivative, the Philadelphia (Ph) chromosome, results from a reciprocal translocation t(9;22) (q34;q11) and is associated with chronic myeloid leukemia (CML). The translocation can be identified at the DNA level in Ph-positive CML by using a probe to the breakpoint cluster region (bcr). In addition, as a result of this translocation an abl-related 210-kd protein with protein tyrosine kinase (PTK) activity is produced. We analyzed 28 cases of Ph-negative CML for rearrangement of the chromosome 22 sequences and found that eight of the 28 show rearrangement of the bcr. When 12 of the Ph- negative cases were independently reviewed, five were indistinguishable from Ph-positive CML on the basis of morphology, peripheral blood film and clinical details. These five also showed bcr rearrangement. The other seven were reclassified as six atypical CML (aCML) and one chronic myelomonocytic leukemia (CMML). None of these seven showed bcr rearrangement. In addition 11 cases of bcr- CML were assayed for abl- related PTK, and no detectable activity was present, whereas p210 phl/abl PTK was observed both in Ph-positive (three cases examined) and Ph-negative, bcr + (four cases examined) CML. Therefore, bcr + CML, whether or not the Ph chromosome is cytogenetically apparent, involves a similar molecular alteration and produces the 210-kd protein with enhanced PTK activity. Furthermore, these cases can be distinguished from Ph-negative bcr- CML by careful evaluation of clinical and hematologic data.

scholarly journals Paternal origin of the rearranged major breakpoint cluster region in chronic myeloid leukemia

Blood ◽  
1994 ◽  
Vol 83 (12) ◽  
pp. 3445-3448 ◽  
Author(s):  
CE Litz ◽  
CM Copenhaver
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Restriction Site ◽  
Molecular Level ◽  
Philadelphia Chromosome ◽  
Chromosome 22 ◽  
Breakpoint Cluster Region ◽  
Cluster Region ◽  
Cytogenetic Studies ◽  
Restriction Site Polymorphisms

Abstract The Philadelphia chromosome, t(9;22), is present in virtually all cases of chronic myeloid leukemia (CML). It has previously been shown by cytogenetic studies that the rearranged chromosome 22 in patients with CML is exclusively maternal in origin. To address this issue at a molecular level, the major breakpoint cluster region (M-bcr) on chromosome 22 was examined using Southern blot assays and M-bcr Pvu II and Mae II restriction site polymorphisms in three CML patients. In all three cases, the rearranged allele was paternal in origin. These results indicate that the paternally derived M-bcr allele may also be involved in the M-bcr rearrangement.

scholarly journals Paternal origin of the rearranged major breakpoint cluster region in chronic myeloid leukemia

Blood ◽  
1994 ◽  
Vol 83 (12) ◽  
pp. 3445-3448
Author(s):  
CE Litz ◽  
CM Copenhaver
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Restriction Site ◽  
Molecular Level ◽  
Philadelphia Chromosome ◽  
Chromosome 22 ◽  
Breakpoint Cluster Region ◽  
Cluster Region ◽  
Cytogenetic Studies ◽  
Restriction Site Polymorphisms

The Philadelphia chromosome, t(9;22), is present in virtually all cases of chronic myeloid leukemia (CML). It has previously been shown by cytogenetic studies that the rearranged chromosome 22 in patients with CML is exclusively maternal in origin. To address this issue at a molecular level, the major breakpoint cluster region (M-bcr) on chromosome 22 was examined using Southern blot assays and M-bcr Pvu II and Mae II restriction site polymorphisms in three CML patients. In all three cases, the rearranged allele was paternal in origin. These results indicate that the paternally derived M-bcr allele may also be involved in the M-bcr rearrangement.

scholarly journals Detection of breakpoint cluster region- negative and nonclonal hematopoiesis in vitro and in vivo after transplantation of cells selected in cultures of chronic myeloid leukemia marrow

Blood ◽  
1990 ◽  
Vol 76 (11) ◽  
pp. 2404-2410 ◽  
Author(s):  
AG Turhan ◽  
RK Humphries ◽  
CJ Eaves ◽  
MJ Barnett ◽  
GL Phillips ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Hematopoietic Cells ◽  
Breakpoint Cluster Region ◽  
Cluster Region ◽  
Differentiated Cells ◽  
The One

Abstract Philadelphia (Ph1) chromosome-positive clonogenic progenitors usually disappear within 4 to 6 weeks in long-term cultures established from the marrow of patients with chronic myeloid leukemia (CML). In contrast, coexisting chromosomally normal hematopoietic cells are relatively well maintained. Thus, even though normal cells are initially undetectable, they may become the predominant population. Recently, we have begun to explore the potential of such cultures as a strategy for preparing CML marrow for autografting, and based on cytogenetic studies of the differential kinetics of Ph1-positive and Ph1-negative clonogenic cells, have chosen a 10-day period in culture to obtain maximal numbers of selectively enriched normal stem cells. Here we present the results of molecular analyses of the cells regenerated in vivo for the initial three CML patients to be treated using this approach by comparison with the differentiated cells generated by continued maintenance of an aliquot of the autograft in vitro (using a slightly modified culture feeding procedure to enhance the production and release of cells into the nonadherent fraction after 4 weeks) for the one patient whose genotype made molecular analysis of clonality status also possible. These analyses showed that cells with a rearranged breakpoint cluster region (BCR) gene were not detectable by Southern blotting in either in vitro or in vivo populations of mature cells that might be assumed to represent the progeny of primitive cells present at the end of the initial 10 days in culture. Production of BCR- negative cells was also shown to be temporally correlated with the appearance of nonclonal hematopoietic cells both in culture and in vivo. These findings provide support for the view that prolonged maintenance of CML marrow cells in long-term culture may allow molecular characterization of both the BCR-genotype and clonality status of cells with in vivo regenerative potential.

Variant Philadelphia Translocation with BCR/ABL Fusion Gene Site In 10q24 In a Case of Chronic Myeloid Leukemia

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4839-4839
Author(s):  
Rossana Bonomi ◽  
Pablo Lopez ◽  
Daniela Infante ◽  
Isabel Moro ◽  
Victoria Elizondo ◽  
...  
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Peripheral Blood ◽  
Myeloid Leukemia ◽  
Fusion Gene ◽  
Chromosome 9 ◽  
Chromosome 22 ◽  
Fish Analysis ◽  
Signal Pattern ◽  
Ph Chromosome ◽  
Fusion Signal

Abstract Abstract 4839 Introduction. Chronic myeloid leukemia (CML) is characterized by the Philadelphia chromosome (Ph) observed in more than 90% of patients with CML as a result of t(9;22)(q34;q11), leading to the formation of chimeric gene BCR/ABL encoding for proteins with abnormal tyrosine kinase activity. Cytogenetic variants of Ph chromosome can be identifed in 5 to 10% of CML patients, involving additional chromosomes other than 9 and 22. To explain the formation of variant translocations one-step, two-step and multi-step mechanisms have been proposed. Rarely, the variant Ph chromosome results from a BCR insertion on the ABL region and form a BCR/ABL fusion gene, generally mapping to 9q34, instead of the usual location at 22q11. In very few variant Ph cases, the insertion of the BCR/ABL product in a third chromosome was demonstrated. Case Report 28 year-old man, with bilateral central scotoma and gingivorragia. Physical examination: Grade 4 splenomegaly. Peripheral blood count showed hemoglobin concentration 11.5 g/dl, platelet count: 300.000/mm3, and white blood cell count 590.000/mm3. Blood smear: myelemia exhibiting 30% of myeloid blasts. Bone marrow biopsy: panmyelosis showing 20% of myeloid blasts. Cytogenetic analysis by G-banding performed in peripheral blood verified the following karyotype: 46, XY, t(9;22;10)(q34;q11;q24)[20] The analysis of the BCR-ABL fusion gene according to standard protocols detected the presence of the b3a2 isoform. Fluorescence in situ hybridization (FISH) studies using dual color dual fusion probes in metaphases showed a signal pattern 1F2G1R. The fusion signal mapped to 10q24, the red signal to 9q34, and the normal green signal to chromosome 22, while a second low intensity green signal mapped to the Ph chromosome. No signal was observed in der(9). Interphase FISH analysis in nuclei (n=200) presented the same signal pattern. Instead of using whole chromosome probes for 9 and 22, we hybridised probes used to detect DiGiorge syndrome. These probes detect gene control ARSA (spectrum green) localized at 22q13 and Tuple1 at 22q11 (spectrum orange). Two signals, green and orange were identified in normal chromosome 22. Ph chromosome showed the orange signal, whereas the green signal mapped to der(10). Discussion. The localization of the hybrid BCR/ABL gene on chromosomes other than 22q is a rare event wich can only be detected by FISH techniques. When these unusual translocation occurs, the hypothesis most often put forward is that several consecutive chromosome rearrangements have taken place. In the present case the interpretation of karyotypes, FISH data and molecular evidence lead to the following hypothesis: Insertion of the BCR sequence from chromosome 22 to chromosome 9 may have ocurred, producing a BCR/ABL fusion in der(9). The Ph chromosome detected by G-banding showed a different green fluorescence intensity in the metaphase FISH signal pattern with BCR/ABL dual color dual fusion probes, as a result of an insertion on chromosome 9. This first event was followed by the translocation between the derivative 9 and chromosome 10, being the final localization of the BCR/ABL gene in 10q24. FISH analysis using a DiGeorge syndrome probe, supports the hypothesis of a multistep mechanism underlying insertion and translocations events in the present case. The relocation of BCR/ABL fusion sequence on sites other than chromosme 22q11 represent a rare type of variant Ph translocation. At least 21 cases described in the literature, showed fusion gene BCR/ABL located at 9q24. Only 12 patients with variant Ph were reported bearing BCR/ABL on a third chromosome. All of them involved a masked Ph chromosome. To our best knowledge this is the first report showing a variant Ph chromosome detected by G-banding in a CML patient due to a BCR insertion on ABL sequences and exhibiting the fusion signal in a third chromosome. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Philadelphia-negative (Ph-) chronic myeloid leukemia (CML): comparison with Ph+ CML and chronic myelomonocytic leukemia. The Groupe Francais de Cytogenetique Hematologique

Blood ◽  
1991 ◽  
Vol 78 (1) ◽  
pp. 205-211 ◽  
Author(s):  
P Martiat ◽  
JL Michaux ◽  
J Rodhain
Keyword(s):  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Chronic Phase ◽  
Chronic Myelomonocytic Leukemia ◽  
Ras Mutation ◽  
Ph Chromosome ◽  
Polymerase Chain ◽  
Atypical Cml ◽  
Myelomonocytic Leukemia ◽  
Monocytic Lineage

To better understand the Philadelphia-negative (Ph-) chronic myeloid leukemia (CML) and its relationships with Philadelphia-positive (Ph+) CML and chronic myelomonocytic leukemia (CMML), a study was undertaken by the Groupe Francais de Cytogenetique Hematologique. Thirty-five Ph- CML patients were investigated and compared with 55 chronic phase Ph+ CML and 100 CMML patients. There were 12 M-BCR positive (M-BCR+) and 23 M-BCR negative (MBCR+) patients. No clinical or biologic differences were found between Ph+ and Ph-, M-BCR+ patients. In the Ph- group, M- BCR+ and M-BCR- patients differed significantly in age (47.7 +/- 6.6 v 67.0 +/- 6.1 years, respectively; P = .001), leukocytosis (153.4 +/- 135.1 v 58.5 +/- 37.7 10(9)/L, P = .002), relative monocytosis (1.8% +/- 1.2% v 5.6% +/- 1.4%, P = .048), absolute basophilia (8.5 +/- 9.7 v 0.9 +/- 1.5 10(9)/L, P = .001), percentage of immature myeloid precursors (IMP) in peripheral blood (29.0% +/- 9.5% v 15.3% +/- 8.1%, P = .001), and percentage of erythroblasts in bone marrow (BM) (6.5% +/- 3.5% v 14.6% +/- 3.6%, P = .001). Karyotypic abnormalities other than the Ph chromosome occurred in 0 of 12 M-BCR- at diagnosis and 7 of 23 M-BCR- Ph- CML (P = .033). None of the 13 investigated BCR- patients had detectable BCR/ABL transcripts using polymerase chain reaction (PCR) and none had an N-RAS mutation. Cytologic findings showed a marked morphologic difference between M-BCR+ and M-BCR- patients, especially in the monocytic lineage. Dysmyelopoietic features in CMML and M-BCR- patients were very similar, and the differences were of quantitative order only. Using four criteria (monocytosis, percentage of IMP, basophilia, and percentage of erythroblasts in BM), patients could be divided into typical and atypical CML and this classification correlated well with molecular findings. We conclude that, while Ph-, M- BCR+, and Ph+ CML are identical diseases, Ph-, M-BCR- CML, and CMML have many similarities and might be only different aspects of a same entity.

scholarly journals Aberrant methylation of the major breakpoint cluster region in chronic myeloid leukemia

Blood ◽  
1996 ◽  
Vol 88 (6) ◽  
pp. 2241-2249 ◽  
Author(s):  
CE Litz ◽  
JA Vos ◽  
CM Copenhaver
Keyword(s):  
Sequence Analysis ◽  
Chronic Myeloid Leukemia ◽  
Myeloid Leukemia ◽  
Philadelphia Chromosome ◽  
Nucleotide Position ◽  
Aberrant Methylation ◽  
Breakpoint Cluster Region ◽  
Cluster Region ◽  
Breakpoint Location

Isolated hypomethylated sites exist in the major breakpoint cluster region (M-bcr) where most Philadelphia chromosome (Ph) breakpoints are located. Twenty of 50 (40%) chronic myeloid leukemia (CML) patients were found to have aberrant hypermethylation of these sites on the rearranged M-bcr when compared with control marrows. The aberrancy correlated strongly with M-bcr breakpoint location; 19 of 20 cases had breakpoints located 5′ of the M-bcr Sca I site, and 28 of 30 cases with normal M-bcr methylation had breakpoints located 3′ of the M-bcr Sca I site. Sequence analysis of the Ph M-bcr breakpoints failed to find an M- bcr nucleotide position that delineated the transition between abnormally and normally methylated cases, indicating that the translocation of a critical M-bcr sequence was not responsible for the methylation abnormality. In 3 of 8 CML patients, cells without the t(9;22) were found to have abnormally methylated, unrearranged M-bcrs. The data indicate that abnormally methylated rearranged M-bcrs are present in CML cases with Ph breakpoints 5′ of the M-bcr Sca I site and that the M-bcr in Ph- cells of patients with CML may also be abnormally methylated.

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