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Biomedical subjects

M T Daniel

Publications and source records attributed to M T Daniel.

At least 37 records · Page 2Linked to original sources

Chromosome abnormalities of the short arm of chromosome 12 in hematopoietic malignancies: a report including three novel translocations involving the TEL/ETV6 gene.

A wide variety of abnormalities of the short arm of chromosome 12 has been reported in hematologic malignancies. The most frequent rearrangements result from t(12;21)(p13;q22) of childhood acute lymphoblastic leukemia, a translocation cryptic when leukemic cells are analyzed with chromosome banding techniques. This translocation results in a fusion of the TEL/ETV6 and AML1 genes. In this report, examples of rearrangements of 12p are presented. Study of two complex chromosome abnormalities associated with t(12;21) emphasizes the importance of using FISH in detection of such translocations. Three novel translocations involving the TEL/ETV6 gene localized on 12p13 are also reported: t(X;12)(q28;p13), t(1;12)(q21;p13), and t(9;12)(p23-24;p13). Finally, the presentation of two translocations with breakpoints located centromeric to TEL/ETV6 highlights the not uncommon involvement of genes other than TEL/ETV6 on 12p.

Adolescent↗

Aplastic anaemia in a case of hereditary neutrophil Fcgamma receptor IIIb deficiency.

CD16 antibodies recognize Fcgamma receptors III of a and b types. In a patient with severe idiopathic aplastic anaemia (AA), polymorphonuclear cells, which in normal subjects express FcgammaRIIIb, were found to be CD16 negative. The FcgammaRIIIb gene configuration was analysed by PCR on peripheral blood mononuclear cells. Bi-allelic deletion encompassing at least part of the coding exon 5 was found in the patient and his brother, suggesting a hereditary defect. The patient underwent successful bone marrow transplantation from his HLA-matched brother despite a similar phenotype and genotype. This observation suggests that FcgammaRIIIb hereditary deficiency in donor and/or recipient does not impair engraftment and justifies the use of other monoclonal antibodies in addition to CD16 in the study of GPI-anchored antigen expression.

Adult↗

TEL-AML1 fusion RNA as a new target to detect minimal residual disease in pediatric B-cell precursor acute lymphoblastic leukemia.

It has recently been shown that the t(12;21)(p13;q22) translocation fuses two genes, TEL on chromosome 12 and AML1 on chromosome 21. We have evaluated the frequency of this newly described translocation in acute lymphoblastic leukemia (ALL), and the feasibility of minimal residual disease (MRD) monitoring by polymerase chain reaction (PCR) amplification of TEL-AML1 transcripts. Thirty-nine adult- and 45 childhood-ALLs consecutively diagnosed in a single center were included in this study. TEL-AML1 fusion transcripts were searched for in the 39 adult- and 45 childhood-ALLs for which material was available. BCR-ABL, E2A-PBX1, and MLL-AF4 transcripts were also studied by PCR in these cases. TEL-AML1 transcripts were found in 8 out of 35 (23%) childhood B-cell precursor ALLs (BCP-ALLs). TEL-AML1 transcripts were detected in only 1 of 31 adult BCP-ALLs (P = .04, Fisher's exact test). Nevertheless, in this adult case, TEL-AML1 transcripts were found at a low level in 2 of 3 different samples. BCR-ABL, E2A-PBX1, and MLL-AF4 transcripts were found in 12, 3, and 1 cases of 31 adult BCP-ALLs, and in 1, 2, and 1 cases of 35 childhood BCP-ALLs, respectively. TEL-AML1 transcripts were never found associated with any other fusion transcripts. Taken together, the four types of chimeric transcripts were detected in 12 of 35 (34%) childhood BCP-ALL cases. No TEL-AML1 transcripts were detected in 11 T-cell ALLs (4 adults and 5 children), nor in 2 B-cell (slg+) ALLs. MRD was evaluated in 21 samples collected in 9 TEL-AML1+ childhood BCP-ALL cases during therapy (median follow-up = 200 days). Of 8 patients evaluated after induction therapy, 4 showed detectable but low levels of MRD. Of 7 patients serially evaluated, only one showed persistence of detectable MRD. This study shows that TEL-AML1 transcripts are frequently detected in pediatric BCP-ALLs and that these transcripts are molecular targets that will simplify the strategy of MRD monitoring in childhood BCP-ALL.

Adolescent↗

Expression of p13MTCP1 is restricted to mature T-cell proliferations with t(X;14) translocations.

T-cell prolymphocytic leukemia (T-PLL), a rare form of mature T-cell leukemias, and ataxia telangiectasia clonal proliferation, a related condition occurring in patients suffering from ataxia telangiectasia, have been associated to translocations involving the 14q32.1 or Xq28 regions, where are located the TCL1 and MTCP1 putative oncogenes, respectively. The MTCP1 gene is involved in the t(X;14)(q28;q11) translocation associated with these T-cell proliferations. Alternative splicing generates type A and B transcripts that potentially encode two entirely distinct proteins; type A transcripts code for a small mitochondrial protein, p8MTCP1, and type B transcripts, containing an additional open reading frame, may code for 107 amino-acid protein, p13MTCP1. The recently cloned TCL1 gene, also involved in translocations and inversions associated with T-cell proliferations, codes for a 14-kD protein that displays significant homology with p13MTCP1. We have generated rabbit antisera against this putative p13MTCP1 protein and screened for expression of p13MTCP1 normal lymphoid tissues and 33 cases of immature and mature lymphoid T-cell proliferations using a sensitive Western blot assay. We also investigated the MTCP1 locus configuration by Southern blot analysis. The p13MTCP1 protein was detected in the three T-cell proliferations with MTCP1 rearrangements because of t(X;14) translocations, but neither in normal resting and activated lymphocytes nor in the other T-cell leukemias. Our data support the hypothesis that p13MTCP1 and p14TCL1 form a new protein family that plays a key role in the pathogenesis of T-PLL and related conditions.

Amino Acid Sequence↗

Chromosome microdissection in leukemia: a powerful tool for the analysis of complex chromosomal rearrangements.

In many human cancers the presence of marker chromosomes or unbalanced translocations prevents complete karyotypic analysis. Chromosome microdissection has become an increasingly important method for assessing chromosome rearrangements. However, most studies using chromosome microdissection have been carried out on established cancer cell lines that provide an unlimited supply of abnormal metaphase cells. We have routinely performed microdissection of as few as three marker chromosome copies from short-term cultures of acute myeloid leukemias, followed by in vitro DNA amplification and fluorescence in situ hybridization (FISH) to normal metaphase spreads. Using this type of "reverse chromosome painting," we were able to characterize precisely the chromosomal constitution of each marker chromosome in the samples, confirming the diagnostic usefulness of microdissection in cancer cytogenetics. In addition, in one leukemia with atypical cytological features, microdissection enabled us to detect a novel retinoic acid receptor alpha gene rearrangement.

Acute Disease↗

Isochromosome 7q and trisomy 8 are consistent primary, non-random chromosomal abnormalities associated with hepatosplenic T gamma/delta lymphoma.

Four patients with hepatosplenic T gamma/delta lymphoma, a rare but distinct entity of peripheral T cell lymphoma, are reported on. In each case, cytogenetic studies showed the presence of an Isochromosome 7q and a trisomy 8. A few chromosome studies have previously been reported in this lymphoma subtype but comparison with these published cases confirms that isochromosome 7q and trisomy 8 are primary, non-random chromosomal abnormalities in hepatosplenic T gamma/delta lymphoma.

Adolescent↗

An interstitial 11q23 deletion proven to be a rearrangement interrupting the MLL gene in an infant with acute myeloblastic leukemia.

Chromosome studies of an infant with acute myeloblastic leukemia (AML), classified as M2 in the FAB nomenclature revealed an unusual karyotype with del(11)(q23) and a marker chromosome resembling a small chromosomal fragment present in all metaphase cells examined. Fluorescence in situ hybridization (FISH) showed the splitting of a YAC probe containing a part of MLL between the del(11) and mar chromosomes. Painting showed that the mar chromosome contained DNA sequences from chromosome 11, but that the centromeric region was not marked by a chromosome 11-specific alphoid probe. The chromosomal breakpoint was located within the MLL gene by Southern blot experiments. The deletion of 11q was thus interstitial. This case illustrates the importance of associating cytogenetics, several FISH techniques, and molecular studies to analyze unusual karyotypes in leukemia.

Chromosome Aberrations↗

Unusual specific cutaneous lesions in myelodysplastic syndromes.

BACKGROUND: Early diagnosis of leukemia cutis in myelodysplastic syndrome (MDS) is important because these lesions can precede acute peripheral blood or bone marrow transformation. Leukemia cutis is usually easy to recognize, but atypical lesions are not well described. OBJECTIVE: Our purpose was to describe unusual specific lesions in MDS. METHODS: Data from patients with myeloid malignancies and leukemia cutis were reviewed. Only patients with MDS and cutaneous lesions different from typical tumors were included. Clinical features were analyzed. RESULTS: Four patients with MDS and unusual specific cutaneous lesions were found. They had ecchymoses, necrotic plaques or ulcers, and prurigo-like lesions. In three of four patients appearance of these skin lesions heralded or was concomitant with acute transformation. CONCLUSION: Specific cutaneous lesions can display unusual patterns. Early biopsy of cutaneous lesions in MDS is indicated.

Aged↗

Leukaemic non-Hodgkin's lymphomas with hyperdiploid cells and t(11;14)(q13;q32): a subtype of mantle cell lymphoma?

The present study describes five patients with leukaemic non-Hodgkin's lymphoma (NHL) detected on the basis of particular morphology and cytogenetic findings. With respect to histological, immunological and cytogenetic features these NHL are closely related to mantle cell lymphoma/intermediate differentiated lymphocytic lymphoma. However, the presence of unusual large cells associated with the t(11;14)(q13;q32) translocation and numerical chromosome changes, in the near triploid or near tetraploid range, could delineate a particular subtype of mantle cell lymphoma.

Aged↗

In vivo thrombin and plasmin activities in patients with acute promyelocytic leukemia (APL): effect of all-trans retinoic acid (ATRA) therapy.

APL-associated hemostasis disorders result from at least two distinct mechanisms due to the release of procoagulant activities and plasminogen activators from the leukemic cells. These two mechanisms (thrombin activation and plasmin activation) may cleave the fibrinogen molecule, but their respective roles in low fibrinogen levels and bleeding diathesis genesis remain in dispute. In vivo ATRA therapy induces a rapid correction of both low fibrinogen level and bleeding tendency, but no clear explanation of this beneficial effect has been proposed. We prospectively investigated 27 APL patients at presentation for diffuse intravascular coagulation (DIC) markers (prothrombin activation fragment and thrombin/antithrombin complexes) and plasmin-dependent primary fibrinogenolysis markers (alpha 2 plasmin inhibitor consumption +/- plasmin/alpha 2 plasmin inhibitor complexes). Fourteen of these patients were then serially studied during the first 2 weeks of ATRA therapy. Four of them, however, developed an hyperleukocytosis requiring additional chemotherapy before the end of the 2nd week. At presentation, low level of fibrinogen was clearly associated with alpha 2 plasmin inhibitor deficiency (p < 0.01), while DIC was equally present in fibrinogenopenic and non-fibrinogenopenic patients. Moreover, was observed a rapid simultaneous correction of low fibrinogen levels and plasmin activation markers in APL patients undergoing ATRA therapy (before day 5), but a more prolonged persistence of DIC markers (until day 14). Initial bleeding syndrome seemed more frequent in patients with initial low fibrinogen level. These data indicate that plasmin-dependent primary fibrinogenolysis is the major etiologic factor of low fibrinogen level in APL patients. In vivo differentiation ATRA therapy induces a rapid decrease in the plasmin activation and a normalization of fibrinogen level, while DIC may in vivo persist for several weeks. Prospective studies evaluating antifibrinolytic agents as therapy of APL-associated hemostasis disorders should be considered. Additionally, prophylactic heparin therapy might be useful after day 5 in patients undergoing ATRA therapy, since they present a prolonged procoagulant tendency.

Adolescent↗

Changes in microrheology of acute promyelocytic leukemia cells during all-trans retinoic acid (ATRA) differentiation therapy: a mechanism for ATRA-induced hyperleukocytosis?

According to French and European experience, hyperleukocytosis occurs during ATRA differentiation therapy in about 70% of de novo and 25% of relapsed APL cases. The most frequently suggested cause for this side-effect is an ATRA-induced proliferation of APL cells. However, no definite explanation for such a proliferative effect has been clearly established. Another mechanism directly related to the differentiation of marrow leukemic cells could be a change in their microrheology, allowing their release from the bone marrow and their transfer toward peripheral blood (PB) and tissues. Using a single cell aspiration assay into a glass restrictive channel, we measured APL cell viscosity values in five de novo APL patients. A deformability index (DI) was defined as the ratio of mean normal neutrophil viscosity x 100/mean APL cell viscosity. Results were the following: (1) at diagnosis, two patients had high marrow DI (96 and 250%) and three patients had low marrow DI (16, 17, and 40%); (2) when PB and marrow APL cells were simultaneously tested, PB APL cells display higher DI than marrow APL-cells; (3) the two patients with high initial marrow DI experienced an ATRA-induced hyperleukocytosis after only 1 day of treatment; (4) in the three patients with low initial marrow DI, the DI was increasing during ATRA therapy and hyperleukocytosis seemed to occur when a large amount of maturing APL cells reached a viscosity value similar to that of mature neutrophils. These results suggest that an asynchronism between rheological and morphological maturation in each APL cell might explain the occurrence of hyperleukocytosis in some patients during ATRA differentiation therapy.

Adult↗

Detection of minimal residual disease in acute myelomonocytic leukemia with abnormal marrow eosinophils by nested polymerase chain reaction with allele specific amplification.

Acute myelomonocytic leukemia with bone marrow eosinophilia (AML-M4Eo in the French-American-British FAB] classification) is frequently associated with pericentric inversion of chromosome 16, inv(16)(p13q22). Recently, the molecular cloning of teh breakpoints has led to the identification of the two fused genes, CBFB on 16q and MYH11 on 16p. We have analyzed 24 patients with AML-M4Eo at diagnosis and 47 patients with AML of other FAB subtypes, by a reverse-transcriptase polymerase chain reaction (RT-PCR) assay for the CBFB/MYH11 fusion mRNAs. Three types of fusion mRNAs were detected in 22 samples of AML-M4Eo (type A, n = 20; type C, n = 1; and type D, n = 1). Among these 22 positive samples, inv(16) was found in the 20 cytogenetically studied cases. No fusion transcript was detected in two patients with AML-M4Eo and in patients with other types of AML. These results confirm that CBFB/MYH11 transcripts (with a predominant type A form) are present in most cases of inv(16) AML. Moreover, detection of the hybrid transcript is closely associated with the finding of abnormal bone marrow (BM) eosinophils in AML-M4Eo as it is not found in other, FAB subtypes of AML, including AML-M4. To assess the presence of type A CBFB/MYH11 fusion transcripts in five AML-M4Eo patients in remission, we designed a sensitive assay combining nested PCR and allele-specific amplification (NPASA). Residual leukemia cells were detected in four patients who were in remission from 4 to 22 months, but not in one patient in long-term remission (5 years). The clinical relevance of persistent CBFB/MYH11 fusion transcripts in remission remains to be established by studying a large prospective series of patients. NPASA provides a useful and sensitive tool for the detection of minimal residual disease in inv(16) AML and, potentially, in other leukemias associated with translocations that result in a predominant fusion transcript.

Alleles↗

The chronic myeloid leukaemias: guidelines for distinguishing chronic granulocytic, atypical chronic myeloid, and chronic myelomonocytic leukaemia. Proposals by the French-American-British Cooperative Leukaemia Group.

We have reviewed our experience with four of the entities that are included under the generic term chronic myeloid leukaemia (CML), namely the classic Ph+ CGL, both BCR+ and BCR-, aCML and CMML. We have developed a statistical model that confirms that CGL, aCML and CMML can be distinguished from each other with reasonable success employing five quantitative parameters (WBC, percentage immature granulocytes, percentage monocytes, percentage basophils, percentage erythroid precursors in bone marrow) and one qualitative parameter (granulocytic dysplasia). It is hoped that these detailed recommendations will enable investigators to improve their diagnostic accuracy. This should permit more uniform comparisons of molecular biologic and clinical studies.

Bone Marrow↗

Translocation t(11;11)(q13;q23) and HRX gene rearrangement associated with therapy-related leukemia in a child previously treated with VP16.

A child with acute myelomonocytic leukemia, bone marrow eosinophilia and inv(16) received first-line therapy including etoposide (VP-16). Cytopenia and monocytosis appeared 7 months after complete remission while the child was treated with maintenance chemotherapy. Blood abnormalities persisted after discontinuation of treatment. Nine months after complete remission, t(11;11)(q13;q23) and HRX rearrangement were detected. Five months later, overt leukemia of monocytic type occurred. The responsibility of VP-16 therapy in this treatment-related acute myelocytic leukemia is discussed.

Adolescent↗

HTLV-1-like particles and HTLV-1-related DNA sequences in an unambiguous case of Sèzary syndrome.

An unambiguous case of Sèzary syndrome associated with the presence of unusual retroviral infection markers is described. The blood smear showed 15% typical Sèzary cells but also rare atypical lymphocytes with convoluted nuclei, evocative of characteristic adult T-cell leukemia (ATL) flower cells. However, the patient did not present any clinical or biological manifestations of ATL, and human T-cell leukemia virus type 1 (HTLV-1) serology was consistently negative. After being cultured for 4 months, peripheral blood mononuclear cells (PBMC) produced typical type C retrovirus-like particles with budding forms strongly resembling HTLV-1 virions. The producer cells did not express HTLV-1-specific antigens detectable by indirect immunofluorescence (IIF). Southern blotting of uncultured PBMC DNA, submitted to digestion with the restriction enzymes PstI and SacI, and hybridized with a full genomic HTLV-1 probe, showed the presence of specific homologous sequences, absent in all of the healthy donor control PBMC DNAs. These HTLV-1-like sequences presented a restriction enzyme pattern distinct from that of the HTLV-1 prototype genome and of other HTLV-1 proviruses studied up to now. Polymerase chain reaction (PCR) with highly conserved HTLV-1 derived pol and env primers was consistently negative with the patient's DNA. All these results taken together suggest that our patient carries a retroviral agent partially homologous to, but probably different from HTLV-1. The possibility is discussed that this type of retroviral agent might be associated with a subtype of cutaneous T-cell lymphoma (CTCL) represented by a typical Sèzary syndrome with a very low percentage of ATL-like flower cells in the blood smear.

Adult↗