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D Catovsky

Publications and source records attributed to D Catovsky.

At least 145 records · Page 8Linked to original sources
PubMed1996

Molecular cloning of complex chromosomal translocation t(8;14;12)(q24.1;q32.3;q24.1) in a Burkitt lymphoma cell line defines a new gene (BCL7A) with homology to caldesmon.

Chromosome 12q24.1 is a recurrent breakpoint in high-grade B-cell non-Hodgkin lymphoma (B-NHL). To identify the genes involved at 12q24.1, molecular cloning of a three-way translocation t(8;14;12)(q24.1;q32.3;q24.1) in a Burkitt lymphoma cell line (Wien 133) was performed; all four translocation breakpoints were cloned and sequenced. Analysis of clones encompassing the der(12)(12;14)(q24.1;q32.3) breakpoint showed a CpG island from chromosome 12q24.1 juxtaposed in a tail-to-tail configuration with a productively rearranged Ig VH4-DH-JH5 gene. A total of 4.5 kb of genomic DNA including the CpG island was sequenced and analyzed using gene-identification programs; all three programs identified a potential 92-bp exon within the centromeric boundary of the CpG island. Using this as a probe, an RNA transcript of 3.8 kb, expressed at low levels in a wide variety of normal tissues, was detected. Overlapping cDNA clones were isolated and sequenced. The longest open-reading frame predicted a serine-rich protein of 231 amino acids. This protein, termed BCL7A, exhibited no recognizable protein motifs but showed homology with the actin-binding protein, caldesmon. In Wien 133, the BCL7A breakpoint occurred within the first intron and resulted in a MYC-BCL7A fusion transcript, with exon I of BCL7A being replaced by MYC exon I. The normal, untranslocated allele of BCL7A was also expressed without mutation. One of the 11 other B-NHL cell lines examined with 12q24.1 cytogenetic abnormalities, a mediastinal B-NHL cell line (Karpas 1106), showed biallelic rearrangement within the first intron of BCL7A, which was adjacent to the breakpoint observed in Wien 133. Disruption of the amino-terminus of BCL7A defines a new mechanism in the pathogenesis of a subset of high-grade B-NHL.

Amino Acid Sequence↗
PubMed1996

C-kit receptor (CD117) expression in acute leukemia.

The murine monoclonal antibody YB5.B8 (CD117) identifies a transmembrane tyrosine kinase receptor encoded by the human c-kit proto-oncogene. In this study we investigated the expression of c-kit on different types of acute leukemia to determine the degree of specificity and sensitivity of this marker for the myeloid and lymphoid lineages. C-kit was positive in over half of the 115 cases of acute leukemia studied. Overall, two thirds of AML cases expressed c-kit, whereas only one of 23 ALL patients was c-kit positive. C-kit was also positive in 16 of 19 cases of myeloid blast crisis of myeloproliferative disorders and negative in four with a lymphoid phenotype. There was no correlation between c-kit expression and the degree of myeloid differentiation by FAB subtypes or other markers. We conclude that c-kit is a specific marker for the myeloid lineage, which is expressed early during hematopoietic differentiation and can aid the diagnosis of AML in difficult cases. More patients need to be tested to establish whether the expression of c-kit may define AML subgroups of prognostic significance.

Acute Disease↗
PubMed1996

Humanized CD52 monoclonal antibody Campath-1H as first-line treatment in chronic lymphocytic leukaemia.

The humanized CD52 monoclonal antibody Campath-1H was used as first-line therapy in nine patients with progressive chronic lymphocytic leukaemia (CLL). Intravenous (n = 5) or subcutaneous (n = 4) injections (up to 30 mg/inj.) were given three times a week for a maximum of 18 weeks. Three patients achieved a complete remission (CR) and five patients a partial remission (PR) (response rate 89%). CLL cells were cleared from blood in all patients and from the bone marrow in seven patients. The response duration time was 8 + -24+ months. Adverse events were mild except for one patient who developed CMV pneumonitis. All patients developed lymphocytopenia (B and T cells) but other haematological toxicities were negligible. Campath-1H is a highly effective and well-tolerated agent in patients with previously untreated CLL and further studies are warranted.

Adult↗
PubMed1996

2-Chlorodeoxyadenosine in the treatment of hairy cell leukaemia: differences in response in patients with and without abdominal lymphadenopathy.

We treated 26 patients with hairy cell leukaemia (HCL) with 2-chlorodeoxyadenosine, including nine with abdominal lymphadenopathy and of whom two had HCL-variant; 18 were previously treated. The overall response in 23 evaluable HCL patients was 100% with 87% complete remission (CR). The CR rate was 57% in patients with abdominal lymphadenopathy. Neither of the patients with HCL-variant achieved CR. Of four patients who had become refractory to 2'-deoxycoformycin, two achieved CR and one partial remission (PR). The lower response in HCL with abdominal lymphadenopathy supports the view that this represents a more resistant form of the disease.

Adult↗
PubMed1996

Trisomy 12 defines a group of CLL with atypical morphology: correlation between cytogenetic, clinical and laboratory features in 544 patients.

We have analysed the clinical and laboratory features in 544 patients with chronic lymphocytic leukaemia (CLL) with available cytogenetics and fluorescence in-situ hybridization (FISH) analysis for trisomy 12 in half of them, to examine the correlation between chromosome abnormalities and clinical or laboratory parameters. Five chromosome groups were defined: (1) trisomy 12 (18%), detected as the sole abnormality or associated with other changes; (2) del(13)(q12-14) (7%); (3) other abnormal karyotypes (20%); (4) normal karyotype (41%); and (5) no divisions (14%). There were no differences in the age distribution between the five groups. Clinical stages (Binet) were: A (74%), B (12%) and C (14%). Stage A was common in cases with del(13q)(82%), normal (84%) and other abnormal karyotypes (74%), whereas it was less common in trisomy 12 cases (64%) and those with no divisions (48%). Typical CLL morphology was found in 83% of cases; 10% had more than 10% prolymphocytes (CLL/PL) and 7% had other atypical features. CLL with trisomy 12 was the only group with a high frequency of either CLL/PL (31%) or atypical morphology (24%). Atypical morphology and CLL/PL were even more frequent when trisomy 12 was associated with other chromosomal abnormalities (70% v 46%). The incidence of cases with CLL/PL and other atypical morphology was significantly lower in the other chromosome groups (P < 0.001). There were no differences in immunophenotype among the various groups except for a higher frequency of stronger Smlg and FMC7 expression in cases with trisomy 12, particularly those with CLL/PL and other atypical morphology. Our findings confirm that trisomy 12 defines a subgroup of CLL with more frequent atypical morphology, including CLL/PL, stronger SmIg and FMC7 expression, more advanced stages (B and C in 18%) and possibly worse prognosis.

Aged↗
PubMed1996

Platinum agents and secondary myeloid leukaemia: two cases treated only with platinum-based drugs.

With the increasing use of chemotherapy for many different primary malignancies, secondary or therapy-related acute myeloid leukaemias (AML) and myelodysplastic syndromes (MDS) are becoming more common. The risk of developing sAML has been estimated to be between 2% and 10%, depending upon the type, duration and dosage of previous therapy (Michels et al, 1985; Shulman, 1993; Robinson & Mertens, 1993; Ballen & Antin, 1993). It is therefore one of the most serious long-term complications of current cancer treatment and is likely to increase as longer survival rates for the primary tumour are achieved. An increasing range of drugs have been reported to cause sAML, including the alkylating agents, the epipodophyllotoxins and the anthracyclines, both as single agents and in combination (Pedersen-Bjergaard & Philip, 1991; Pedersen-Bjergaard & Rowley, 1994). We report two cases of secondary AML in which platinum compounds were the sole prior chemotherapy.

Acute Disease↗
PubMed1996

Differential expression of CD3 and CD7 in T-cell malignancies: a quantitative study by flow cytometry.

Most T-cell antigens are expressed on normal and neoplastic T lymphocytes and for this reason it is not easy to distinguish between the immunophenotype of normal and malignant T cells. We have addressed this problem by comparing the levels of expression of CD3 and CD7 on T lymphocytes from 18 healthy donors with those of 61 cases of T-cell leukaemia using quantitative flow cytometry with a method that converts fluorescence intensity into number of antigen molecules per cell. Normal T lymphocytes expressed 124 +/- 25 CD3 and 20 +/- 3 x 10(3) CD7 molecules per cell. The mean CD3 values were significantly lower in all types of T-cell leukaemia than in normal T cells (P < 0.05), with the exception of Sezary syndrome. The lowest CD3 values were found in T-lymphoblastic leukaemia (T-ALL), 30 +/- 21 x 10(3), and adult T-cell leukaemia/lymphoma (ATLL), 38 +/- 31 x 10(3), followed by T-prolymphocytic leukaemia (T-PLL), 92 +/- 47 x 10(3), and granular lymphocyte leukaemia (GLL), 95 +/- 21 x 10(3). In contrast, the number of CD7 molecules was significantly higher in T-All, 35 +/- 7 x 10(3) (P < 0.01), and T-PLL, 29 +/- 12 x 10(3), than the normal controls (P < 0.01), whereas ATLL and GLL showed a low CD7 expression, 13 +/- 3 and 12 +/- 3 x 10(3), respectively. Our results show that the quantitative analysis of CD3 and CD7 and their combined evaluation may enable a distinction between normal and leukaemic T cells and could facilitate the monitoring of minimal residual disease. This study has also defined the T prolymphocyte as a cell of intermediate maturity between thymic derived and peripheral T lymphocytes.

Antigens, CD7↗
PubMed1996

The ultrastructure of mantle cell lymphoma and other B-cell disorders with translocation t(11;14)(q13;q32).

We conducted an ultrastructural study in 22 cases of B-lymphoproliferative disorders in leukaemic phase bearing the t(11;14) translocation. The features of peripheral blood leukaemic cells in nine cases of mantle cell lymphoma (MCL) were compared to those diagnosed as B-prolymphocytic leukaemia (B-PLL) (five cases), splenic lymphoma with villous lymphocytes (SLVL) (four cases), lymphoplasmocytic lymphoma (LPL) (one case), chronic lymphocytic leukaemia with > 10% prolymphocytes (CLL/ PL) (one case) and unclassified B-non Hodgkin's lymphoma (B-NHL) (two cases). The ultrastructural characteristics were also compared to those present in B-NHL without t(11;14), including cases of follicular centre lymphoma (FCL). This study shows that MCL has distinct ultrastructural features including a cleaved or indented nucleus with an even heterochromatin distribution, an absent or inconspicuous nucleolus, low N/C ratio, abundant mitochondria, a well developed Golgi zone, profiles of endoplasmic reticulum and centrioles. This pattern clearly differs from that found in FCL cells. The nuclear pattern of MCL cells also differed from the cells in the other disorders with t(11;14), but shared an organelle-rich cytoplasm, and features which were not apparent in cases without t(11;14). The cytoplasmic changes observed in cells bearing t(11;14) suggest increased cellular activity which may relate to the chromosome translocation and the resulting over-expression of bcl-1.

B-Lymphocytes↗
PubMed1996

Expression of TIA-1 and TIA-2 in T cell malignancies and T cell lymphocytosis.

OBJECTIVE: To investigate the reactivity with TIA-1 and TIA-2, two monoclonal antibodies that recognise, respectively, granular structures in T lymphocytes and the T cell receptor chain in cells from a variety of T cell disorders. METHODS: Cytoplasmic staining with TIA-1 and TIA-2 was carried out by the immunoalkaline phosphatase anti-alkaline phosphatase technique in 67 cases with a T cell disorder: 31 large granular lymphocyte (LGL) leukaemia, nine T-prolymphocytic leukaemia (T-PLL), five Sezary syndrome, four peripheral T cell lymphoma (PTCL), 13 T cell lymphocytosis, and five T-acute lymphoblastic leukaemia (T-ALL). All had over 75% abnormal T cells which were CD2+, CD3+, CD5+, CD7+, and negative with B cell markers. RESULTS: TIA-1 was positive in 77% cases of LGL leukaemia and half of the PTCL and T-ALL, whereas it was negative in all Sezary syndrome and most T-PLL (8/9) and reactive T-lymphocytosis (10/13). In LGL leukaemia, TIA-1 was positive irrespective of the membrane phenotype, whether CD8+, CD4- or CD4+, CD8-, and was more often positive in cases where cells were CD16+, CD56+, or CD57+. TIA-2 was positive in 60% of cases encompassing all diagnostic types of T cell disorder. There was no correlation between TIA-2 expression and that of other T cell markers, activation antigens, and natural killer markers. CONCLUSIONS: The pattern of TIA-1 expression in T cell malignancies may help in the differential diagnosis among LGL leukaemia (high expression), T cell lymphocytosis and other T cell diseases (low expression). As TIA-2 is expressed in over 95% mature T lymphocytes and thymic cells, its assessment may be useful to demonstrate aberrant phenotypes which can be exploited for detecting minimal residual disease.

Antibodies, Monoclonal↗
PubMed1996

Association between sarcoidosis and lymphoma revisited.

AIMS: To investigate the relation between sarcoidosis and lymphoma. METHODS: The hospital notes of five patients with sarcoidosis and a lymphoproliferative disorder were reviewed. Histological material on which the diagnoses of sarcoidosis and lymphoma were made was re-analysed. RESULTS: Four of the five patients had well documented sarcoidosis preceding the development of lymphoma by 18 months to 28 years; the fifth patient had lymphoplasmacytic lymphoma with a reactive granuloma reaction. Two patients had chronic sarcoidosis and three were treated with prednisolone. The types of lymphoma were: Hodgkin's disease (n = 1), B cell lymphoma (n = 2) (mantle cell and lymphoplasmacytic/local plasmacytoma) and large granular lymphocyte leukaemia (T cell) (n = 1). CONCLUSIONS: The association between sarcoidosis and lymphoma is confirmed, suggesting that sarcoidosis may be a predisposing factor for the development of a lymphoid malignancy due to disturbance of the immune system. All types of lymphoma may develop. The first case of T cell granular lymphocytic leukaemia in a patient with sarcoidosis has been documented.

Adult↗
PubMed1996

Differential expression of T cell antigens in normal peripheral blood lymphocytes: a quantitative analysis by flow cytometry.

AIMS: To obtain reference values of the level of expression of T cell antigens on normal lymphocyte subsets in order to disclose differences which could reflect their function or maturation stages, or both. METHODS: Peripheral blood from 15 healthy donors was processed by flow cytometry with triple colour analysis. For each sample phycoerythrin (PE) conjugated CD2, CD4, CD5, CD8, and CD56 monoclonal antibodies were combined with Cy5-R-phycoerythrin (TC) conjugated CD3 and fluorescein isothiocyanate (FITC) conjugated CD7; CD2- and CD7-PE were also combined with CD3-TC and CD4-FITC. Standard microbeads with different capacities to bind mouse immunoglobulins were used to convert the mean fluorescence intensity (MFI) values of the lymphocyte subsets identified by multiparametric flow cytometry into the number of antigen molecules per cell, measured as antibody binding capacity (ABC). RESULTS: CD4+ (helper/inducer) T cells exhibit a higher CD3 antigen expression compared with CD8+ (suppressor/ cytotoxic) T lymphocytes. Within the CD4+ T cells, the CD4+CD7- subset expressed a lower level of CD3 compared with CD4+CD7+ and CD8+CD7+ cells, and higher CD2 and CD5 expression than the main CD3+CD7+ subset. Major differences in antigen expression were also detected between CD3+ T cells and CD3-CD56+ natural killer (NK) cells: NK cells exhibited higher levels of CD7 and CD56 and lower levels of CD2 and CD5 than T cells. Significantly lower CD5 expression was also detected in the small CD5+ B lymphocyte subset compared with T cells. CONCLUSIONS: Quantitative flow cytometry with triple colour analysis may be used to detect antigen modulations in disease states and to increase the accuracy of diagnosis by comparison with findings in normal counterparts.

Adult↗
PubMed1996

Second malignancy in hairy cell leukaemia: no evidence of increased incidence after treatment with interferon alpha.

The last decade has seen a dramatic improvement in prognosis of hairy cell leukaemia (HCL) but concern has emerged with regard to the incidence of second malignancy. A recent report found an 18.8% incidence of second cancers and suggested a possible role for alpha-interferon (IFN) in their pathogenesis. We reviewed our larger series of 200 patients with HCL. We found second malignancies in 8 cases (4.0%), all but one of whom had received IFN. However, when compared to age- and sex- matched population data this represents no increase in relative risk of second cancer in patients with HCL and provides no evidence of a role for IFN in the pathogenesis of these second malignancies.

Adult↗
PubMed1996

Clinical and laboratory features of adult T-cell leukaemia lymphoma in Barbados.

We describe the clinical and pathological features of 23 Afro-Caribbean patients with adult T-cell leukaemia/lymphoma admitted to the Queen Elizabeth Hospital, Barbados over a 5 year period. There were 9 males and 14 females, with a median age of 38 years (range 14-84). Twelve had acute leukaemia, 10 lymphoma (including 4 with solitary extra nodal lesions) and 1 smouldering subtype. Two patients had a past history of tropical spastic paraparesis/HTLV I associated myelopathy (TSP/HAM). The prognosis was poor, with only 3 complete responses to chemotherapy (CHOP) lasting from 9 to 36 months. We conclude that ATLL in Barbados is similar to the disease in the other Caribbean islands and Japan, except that in Barbados the age of onset is over a decade younger than in Japan.

Adolescent↗