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J D Rowley

Publications and source records attributed to J D Rowley.

At least 19 recordsLinked to original sources
PubMed1992

Cloning of cDNAs of the MLL gene that detect DNA rearrangements and altered RNA transcripts in human leukemic cells with 11q23 translocations.

Recurring chromosomal abnormalities involving translocations at chromosome 11 band q23 are associated with human myeloid and lymphoid leukemia as well as lymphoma. We have identified the gene located at this break-point and have named it MLL (for myeloid-lymphoid, or mixed-lineage, leukemia). The t(4;11), t(6;11), t(9;11), and t(11;19) are among the most common reciprocal translocations in leukemia cells involving this chromosomal band. We now have evidence that the breakpoints in all of these translocations are clustered within a 9-kilobase (kb) BamHI genomic region of the MLL gene. By Southern blot hybridization using a 0.7-kb BamHI cDNA fragment of the MLL gene called MLL 0.7B, we have detected rearrangements of DNA from cell lines and patient material with an 11q23 translocation in this region. Northern blot analyses indicate that this gene has multiple transcripts, some of which appear to be lineage-specific. In normal pre-B cells, four transcripts of 12.5, 12.0, 11.5, and 2.0 kb are detected. These transcripts are also present in monocytoid cell lines with additional hybridization to a 5.0-kb transcript, indicating that expression of different-sized MLL transcripts may be associated with normal hematopoietic lineage development. In a cell line with a t(4;11), the expression of the 12.5-, 12.0-, and 11.5-kb transcripts is reduced, and there is evidence of three other altered transcripts of 11.5, 11.25, and 11.0 kb. Thus, these 11q23 translocations result in rearrangements of the MLL gene and may lead to altered function(s) of MLL and of other gene(s) involved in the translocation.

Chromosome Aberrations↗
PubMed1992

Clinical, morphologic, and cytogenetic characteristics of 26 patients with acute erythroblastic leukemia.

We have performed a retrospective analysis of the clinical, morphologic, and cytogenetic findings in 26 patients diagnosed between January 1969 and September 1991 with acute erythroblastic leukemia de novo (EL or AML-M6). Clonal chromosomal abnormalities were found in 20 (77%) patients (95% confidence interval [CI], 61% to 93%). Loss of all or part of the long arm (q) of chromosomes 5 and/or 7 was observed in 17 (65%) patients (95% CI, 47% to 83%). In addition, the karyotypes were often complex, with multiple abnormalities and subclones. Among the remaining nine patients, six had a normal karyotype and one each had trisomy 8, t(3;3), or t(3;5). The overall frequency of abnormalities of chromosomes 5 and/or 7 observed in our M6 patients is similar to that observed in our patients with therapy-related acute myeloid leukemia (t-AML; 99 of 129 patients, 77%), but substantially higher than that noted in our other patients with AML de novo (French-American-British [FAB] subtypes M1-M5: 52 of 334 patients, 16%). Our M6 patients with abnormalities of chromosomes 5 and/or 7 were older and had a shorter median survival (16 v 77 weeks [P = .005]) than did the M6 patients without these abnormalities. We found no correlation between morphologic features and either cytogenetic abnormalities or clinical outcome. Of note was the finding that the percentage of myeloblasts, which may account for only a small fraction of the total marrow elements when the revised FAB criteria are applied, had no bearing on prognosis. We conclude that acute erythroblastic leukemia, when defined by morphologic criteria, consists of two distinctive subgroups: one group tends to be older, has complex cytogenetic abnormalities, especially of chromosomes 5 and/or 7, and shares biologic and clinical features with t-AML; the other group, with simple or no detectable cytogenetic abnormalities, has a more favorable prognosis when treated with intensive chemotherapy.

Adolescent↗
PubMed1992

Cytogenetic characterization of B-cell lymphomas from severe combined immunodeficiency disease mice given injections of lymphocytes from Epstein-Barr virus-positive donors.

We analyzed the karyotype of 27 B-cell lymphomas of human origin that developed in mice with severe combined immunodeficiency disease following the injection of peripheral blood leukocytes from Epstein-Barr virus-seropositive donors. Three tumors had clonal abnormalities detected with conventional techniques, 2 had trisomy 11, and 1 had a del(6)(q21q25). One other tumor had trisomy 11 detected with fluorescence in situ hybridization. Twelve tumors had a normal karyotype, 11 tumors had nonclonal abnormalities (which included trisomy 9 or 12 in 3 or 2 tumors, respectively), and one tumor had a karyotype of 92,XXXX(75%)/46,XX(25%) by conventional cytogenetic analysis. Trisomy for chromosomes, 9, 11, and 12 are recurring abnormalities that have been observed in lymphomas associated with an immunocompromised state. Clonal or nonclonal abnormalities were observed in 8 of 11 tumors derived from 3 donors whose peripheral lymphocytes induced a high incidence of tumors in mice with severe combined immunodeficiency disease compared with a clonal abnormality and 2 nonclonal abnormal cells in 2 of 5 tumors derived from 3 donors whose lymphocytes induced an intermediate to low incidence. These observations suggest an association between a higher incidence of karyotypically abnormal cells in lymphomas and the increased tumorigenic potential of the lymphocytes that induced these tumors.

Animals↗
PubMed1992

Molecular analysis of deletions of the short arm of chromosome 9 in human gliomas.

Previous studies have suggested that structural abnormalities involving the short arm of chromosome 9 are frequently associated with gliomas. The alpha-, beta-, and omega-interferon (IFNA, IFNB1, and IFNW, respectively) and the methylthioadenosine phosphorylase (MTAP) genes have been mapped to the short arm of chromosome 9, band p22. Homozygous deletions of these genes have been reported in many leukemia- and glioma-derived cell lines. In this report, we present a detailed analysis of partial and complete homozygous or hemizygous deletions of DNA sequences on 9p in human cell lines and primary tumor samples of glioma patients. Ten of 15 (67%) glioma-derived cell lines had hemizygous or homozygous deletion of IFN genes or rearrangement of sequences around these genes, while 13 of 35 (37%) primary glioma tumor samples had hemizygous (8 tumors) or homozygous (5 tumors) deletion of the IFN genes. The shortest region of overlap of these deletions maps in the interval between the centromeric end of the IFN gene cluster and the MTAP gene. In the cell lines and primary tumors examined, these gross genomic alterations were seen only in association with high grade or recurrent gliomas. Our observations confirm that loss of DNA sequences on 9p, particularly the IFN genes, occurs at a significant frequency in gliomas, and may represent an important step in the progression of these tumors. These results are consistent with a model of tumorigenesis in which the development or progression of cancer involves the loss or inactivation of a gene or several genes that normally act to suppress tumorigenesis. One such gene may be located on 9p; this gene may be closely linked to the IFN genes. Nevertheless, loss of the IFN genes, when it occurs, may play an additional role in the progression of these tumors.

Brain Neoplasms↗
PubMed1992

Detection of trisomy 12 in chronic lymphocytic leukemia by fluorescence in situ hybridization to interphase cells: a simple and sensitive method.

Trisomy 12 is the most common cytogenetic abnormality in chronic lymphocytic leukemia (CLL), and a number of studies have suggested that it may be an adverse prognostic indicator. We have evaluated the usefulness of fluorescence in situ hybridization with a chromosome 12-specific probe as a simple means for detecting trisomy 12 in interphase cells. Forty cases of B-cell CLL previously studied with conventional cytogenetic techniques were analyzed with a biotinylated probe to the centromeric region of chromosome 12. Thirty of these retrospective cases could be reevaluated with in situ hybridization. Our analysis showed three hybridization signals (ie, trisomy 12) in interphase cells from seven of seven cases found previously to have trisomy 12. Trisomy 12 was also detected in five additional cases: in one case thought to have a normal karyotype, in two cases that had been inadequate for routine cytogenetic analysis, and in two cases that had been found to have an abnormal karyotype without trisomy 12. In a prospective series of 20 newly accrued CLL cases, all cases were analyzed successfully by in situ hybridization and six (30%) showed trisomy 12. We were able to perform the analysis on routinely prepared and previously Wright-stained peripheral blood smears. We conclude that fluorescence in situ hybridization is a simple means for the detection of trisomy 12 in CLL. The technique is more sensitive than conventional cytogenetic analysis and would be a useful tool in clinical studies.

Chromosomes, Human, Pair 12↗
PubMed1992

Chromosomal loss and deletion are the most common mechanisms for loss of heterozygosity from chromosomes 5 and 7 in malignant myeloid disorders.

We have examined a population of patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) for loss of heterozygosity of polymorphic markers on chromosomes 5 and 7. The rationale for this study was the observation that the majority of patients with therapy-related leukemia (t-AML or t-MDS), resulting from cytotoxic treatment for prior malignancies, have loss of chromosome 5 and/or 7 or deletions involving the long arms of one or both of these chromosomes. This cytogenetic finding suggested that tumor-suppressor genes, important in the development of AML, may be located in these chromosomal regions. We analyzed a total of 60 patients, 43 with primary MDS/AML de novo and 17 with t-MDS/t-AML. Leukemia cells were evaluated for restriction fragment length polymorphisms (RFLPs). Leukemia cell genotypes were compared with lymphoblastoid cell genotypes from the same patients. Two cases of loss of heterozygosity were identified from chromosomes lacking visible deletions: one involving chromosome 5 in a patient with AML de novo who had a visible deletion of 5q at a later stage of the disease, and one involving chromosome 7 in a patient with t-AML. We conclude that allele loss from loci on chromosomes 5 and 7 in MDS/AML, when it occurs, usually results from major deletion or simple chromosome loss, rather than from mitotic recombination or chromosome loss with duplication of the remaining homologue.

Base Sequence↗
PubMed1992

A complex genetic rearrangement in a t(10;14)(q24;q11) associated with T-cell acute lymphoblastic leukemia.

The t(10;14)(q24;q11) is observed in the leukemia cells of 5-10% of cases of T-cell acute lymphoblastic leukemia (T-ALL). Recently, molecular analyses of a number of these translocations revealed simple reciprocal translocations between the T-cell receptor delta chain gene (TCRD) and a region of 10q24. We have characterized, at the molecular level, a t(10;14)(q24;q11) in a patient with T-ALL. The translocation in this case, in contrast to the previous cases, is part of a complex genetic rearrangement. In addition to a reciprocal translocation between the D delta 3 gene segment of TCRD and a region of 10q24, a local inversion occurred within TCRD, involving the D delta 2 and V delta 2 gene segments. As a consequence, the entire joining and constant regions and most of the diversity regions of TCRD are located on the derivative 14 chromosome, whereas the joining and constant regions of TCRA are positioned on the derivative 10 chromosome. The chromosome 10 breakpoint in our patient, as in other t(10;14), clusters within a 9 kb breakpoint region. The occurrence of seven breakpoints within a localized region of chromosome 10 implies the existence of a nearby gene whose activation may have conferred a selective advantage on the leukemia cells. Moreover, as in the previous cases, the translocation in the present study exhibits recombination signal sequences or signal-like sequences adjacent to the breakpoint junction. The presence of such motifs suggests the involvement of the recombinase enzyme system in the generation of this genetic alteration.

Base Sequence↗
PubMed1992

Hyperdiploidy arising from near-haploidy in childhood acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) of childhood is frequently characterized by a hyperdiploid karyotype. Typically, most of the affected chromosomes in the abnormal clone are present in three copies. We have studied two patients with hyperdiploid ALL whose leukemic cells were atypical in that all or most of the chromosomes were present in either two or four copies, raising a suspicion that the observed karyotype arose through duplication of chromosomes in a precursor cell with a near-haploid chromosome number. Analysis of restriction fragment length polymorphisms confirmed that both cases arose from a near-haploid cell; all informative disomic chromosomes tested had loss of heterozygosity. Furthermore, the hyperdiploid karyotypes did not arise via a perfect haploid cell with exactly 23 chromosomes, because tetrasomic chromosomes remained heterozygous. These two patients probably are classified best as near-haploid cases, which often are observed to have a co-existing hyperdiploid clone with a duplicated chromosome set. The distinction between typical hyperdiploidy and hyperdiploidy arising via a near-haploid cell may be clinically important, because the prognosis for patients with a hyperdiploid karyotype is favorable in comparison to that of patients with a near-haploid karyotype.

Adolescent↗
PubMed1992

The der(11) chromosome contains the critical breakpoint junction in the 4;11, 9;11, and 11;19 translocations in acute leukemia.

Translocations involving 11q23 are recurring abnormalities in human acute leukemia cells of either lymphoid or myeloid lineage. Analysis of 13 variant translocations associated with four of these [t(4;11), t(6;11), t(9;11) and t(11;19)] reveals that the der(11) chromosome is conserved in all of them and therefore contains the critical genetic rearrangement. The MLL gene (myeloid/lymphoid leukemia) is involved in each of these translocations. It is transcribed from centromere to telomere. The present analysis indicates that the 5' region of MLL on the der(11) is juxtaposed to the coding sequences of genes on each of the other translocation partners.

Acute Disease↗
PubMed1992

A method for the rapid sequence-independent amplification of microdissected chromosomal material.

We have developed a simple, efficient method by which microdissected material can be amplified directly in the collection container in a few hours. The procedure involves two initial rounds of DNA synthesis with T7 DNA polymerase, using a primer that contains a random pentanucleotide sequence at its 3' end and a defined sequence at its 5' end, followed by PCR amplification with the defined sequence as the primer. The resulting products can be biotinylated and used for fluorescence in situ hybridization (FISH) to confirm their chromosomal location. As few as 17 dissected chromosomal regions provide sufficient material for a specific FISH signal on the appropriate band of metaphase chromosomes. We have obtained a chromosome 6q25-qter-specific painting probe in this way.

Base Sequence↗
PubMed1992

Therapy-related acute myeloid leukemia secondary to inhibitors of topoisomerase II: from the bedside to the target genes.

In the past five years, several groups have reported acute myeloid leukemia (AML) often monoblastic, as a complication of chemotherapy regimens including the epipodophyllotoxins, etoposide and teniposide. This syndrome is distinct clinically, pathologically and cytogenetically from classical therapy-related myelodysplasia and AML. There is also evidence that other topoisomerase II inhibitors, such as the intercalating agents (including doxorubicin, mitoxantrone, and actinomycin D) may be leukemogenic. Furthermore, there may be further interactions from concomitant topoisomerase II inhibitors and alkylating agents. Topoisomerase II inhibitors induce DNA cleavage and other chromosomal aberrations, including sister chromatid exchanges. These clastogenic abnormalities are not fully understood, and may be specific for each cytotoxic agent. Work is in progress to clone breakpoints such as the t(9;11) and t(8;21) and the use of the resultant DNA probes will enhance our understanding of the leukemogenic process. Given the potential diversity in patients with secondary leukemia, cytogenetic studies should be mandatory for both enhancing our knowledge base and guiding treatment in individual patients. Clinicians must also be wary of the leukemogenic potential of 'dose-intense' regimens including agents such as etoposide and doxorubicin.

Acute Disease↗
PubMed1991

Identification of a gene, MLL, that spans the breakpoint in 11q23 translocations associated with human leukemias.

Recurring chromosomal translocations involving chromosome 11, band q23, have been observed in acute lymphoid leukemias and especially in acute myeloid leukemias. We recently showed that breakpoints in four 11q23 translocations, t(4;11)(q21;q23), t(6;11)(q27;q23), t(9;11)(p22;q23), and t(11;19)(q23;p13.3), were contained within a yeast artificial chromosome clone bearing the CD3D and CD3G gene loci. We have identified within the CD3 yeast artificial chromosome a transcription unit that spans the breakpoint junctions of the 4;11, 9;11, and 11;19 translocations, and we describe two other, related transcripts that are upregulated in the RS4;11 cell line. We have named this gene MLL (myeloid/lymphoid, or mixed-lineage, leukemia.

Adult↗
PubMed1991

Therapy-related myelodysplastic syndrome and acute myeloid leukemia in children: correlation between chromosomal abnormalities and prior therapy.

We have studied 20 children with therapy-related myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML) who were 3 months to 16 years old at diagnosis of their primary neoplasm and 1 to 24 years old at diagnosis of their secondary neoplasm. The median interval from initial treatment for the first malignancy to diagnosis of therapy-related MDS or AML was 46 months (range, 12 to 116 months). Twelve patients had chromosomal abnormalities resulting in loss of material from the long arm of chromosomes 5 and/or 7, three patients had abnormalities of chromosome 11 band q23, one patient had both classes of abnormalities, three patients had other abnormalities, and one patient had a normal karyotype. Ten of 12 patients with chromosome 5 and/or 7 abnormalities had been exposed to an alkylating agent, and two of three patients with 11q23 abnormalities had been exposed to an epipodophyllotoxin. The patient with both classes of abnormalities had been exposed to both types of therapy. We conclude that abnormalities of chromosomes 5 and/or 7 are common in children with therapy-related MDS or AML. The proposed relationships between exposure to alkylating agents and abnormalities of chromosomes 5 and/or 7 and between exposure to epipodophyllotoxins and abnormalities of 11q23 are supported in this pediatric series.

Adolescent↗
PubMed1991

Isolation of a yeast artificial chromosome spanning the 8;21 translocation breakpoint t(8;21)(q22;q22.3) in acute myelogenous leukemia.

The 8;21 translocation is one of the most common specific rearrangements in acute myelogenous leukemia. We have identified markers (D21S65 and a Not I boundary clone, Not-42, referred to as probe B) flanking the chromosome 21 translocation breakpoint (21q22.3) that demonstrate physical linkage in normal genomic DNA, by using at least three restriction endonucleases (Not I, Sac II, and BssHII), and that are located not more than 250-280 kilobases apart. Pulsed-field gel analysis of DNA from somatic cell hybrids containing the 8;21 translocation chromosomes demonstrates rearrangement of these markers. A 470-kilobase yeast artificial chromosome, YAC-Not-42, has been isolated that contains both probes. Mapping of lambda subclones constructed from YAC-Not-42 suggests that greater than 95% (25/26 probes tested) of the yeast artificial chromosome DNA is located on the proximal (D21S65) side of the breakpoint. In situ hybridization studies using metaphase chromosomes from five acute myelogenous leukemia patients with the 8;21 translocation confirmed these results and demonstrated the translocation of probe B to the derivative chromosome 8. A chromosome walk of approximately 39 kilobases from probe B has allowed identification of the breakpoint in DNA from a somatic cell hybrid containing the derivative chromosome 8. Since probe B contains conserved DNA sequences and is in close proximity to the translocation breakpoint, it may represent a portion of the involved gene on chromosome 21.

Blotting, Southern↗
PubMed1991

The LCK gene is involved in the t(1;7)(p34;q34) in the T-cell acute lymphoblastic leukemia derived cell line, HSB-2.

HSB-2 is a cell line derived from a patient who had T-cell acute lymphoblastic leukemia (T-cell ALL) with a t(1;7)(p34;q34). We used a genomic probe from the T-cell receptor beta (TCR beta) locus (7q34) to identify DNA rearrangements in HSB-2. Two rearranged BglII DNA fragments were cloned, and one of these clones was shown to contain the translocation breakpoint on the derivative chromosome I [der(I)]. We used a probe derived from this clone to isolate an unrearranged phage clone encompassing the breakpoint at Ip34. The restriction map of this clone was compared to the published maps of known protooncogenes located at Ip32-34. By restriction mapping, Southern blot analysis, and DNA sequencing we showed that the translocation breakpoint on chromosome I is located within the first intron of the LCK gene. The LCK gene codes for p56lck, a member of the SRC family of cytoplasmic tyrosine protein kinases. There are two classes of LCK transcripts (type I and type II), each expressed from a distinct promoter, and each having a unique 5' untranslated region (UTR); the protein coding regions of the two classes are identical. The breakpoint in the t(1;7) separates the two LCK promoters and juxtaposes the constant region of the TCR beta locus with the proximal promoter and with the protein-coding region of the LCK gene on the der(I) chromosome.

Base Sequence↗