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M Sessarego

Publications and source records attributed to M Sessarego.

At least 91 records · Page 5Linked to original sources
PubMed1989

Cytogenetic follow-up after bone marrow transplantation for Philadelphia-positive chronic myeloid leukemia.

Forty-eight consecutive patients affected by chronic myelogenous leukemia (CML) Philadelphia (Ph) chromosome positive during the chronic phase of the disease underwent allogeneic bone marrow transplantation (BMT). Thirty-five patients had a follow-up over 12 months and were included in a cytogenetic study in order to evaluate the Ph clone eradication. In 25 cases, the Ph chromosome disappeared in all cytogenetic studies, and their hematologic picture is at present apparently normal. Ten patients showed cytogenetic relapse. In one case, the cytogenetic relapse was transitory without any clinical sign of the disease; in three cases, after a transitory cytogenetic relapse, a persistent relapse with clinical picture of progression of the disease occurred; in six cases cytogenetic and a clinical relapse were coincident. Structural chromosomal abnormalities other than Ph were temporarily seen in three cases. The so-called "nonrandom" chromosomal changes typical of the blastic phase were never detected. The reappearing Ph-positive clone spontaneously disappeared in three patients, and their hematologic picture reverted to complete chimerism. The present study confirms that the eradication of the Ph clone is often defective with BMT, and cytogenetic analysis can detect the competition between donor and residual host marrow. Furthermore, the karyotype evolution is different from that found in CML patients treated with conventional chemotherapy.

Bone Marrow↗
PubMed1989

Studies on the oncogenic potential of Epstein-Barr-virus (EBV)-infected B cells in AIDS-related disorders.

Spontaneous lymphoblastoid cell lines (LCLs) were established from the peripheral blood of 10 human immunodeficiency virus (HIV)-seropositive patients in order to investigate whether or not progression of the cells towards a malignant state could be traced. The LCLs studied displayed no differences in their surface phenotype, karyotype, and tumorigenicity in nude mice as compared with a wide panel of control LCLs. Furthermore, no c-myc rearrangement could be detected in any of the LCLs. However, 4 of the 10 LCLs derived from HIV-seropositive patients formed colonies in agar with a cloning efficiency of 0.1-0.9%. This percentage was much lower than that of a control neoplastic B cell line (50%), but consistently higher than that observed for a battery of spontaneous LCLs. The cells of a number of sublines that were derived from the agar colonies expressed new activation markers (CD10 and Bac-1) but did not induce tumors in nude mice or display chromosomal abnormalities. These sublines might comprise cells that have progressed towards a more markedly transformed state.

Animals↗
PubMed1989

Molecular analysis of Philadelphia-negative myeloproliferative syndromes with i(17q).

We report two cases of myeloproliferative syndromes in which the only karyotypic abnormality was an isochromosome of the long arm of chromosome 17. Because i(17q) is a nonrandom structural aberration found in nearly 12% of cases of Philadelphia (Ph)-positive chronic myelogenous leukemia (CML), we carried out a molecular analysis of the breakpoint cluster region (bcr) to verify the presence of genomic rearrangements characteristic of CML. The interest of the study was strengthened by the fact that i(17q) is frequently seen in CML and by recent reports showing that genomic changes of c-abl and bcr genes can be present even in the absence of a Ph chromosome. One of the two patients showed the presence of a rearranged fragment within the bcr, suggesting a Ph-positive CML diagnosis.

Adult↗
PubMed1989

ins(6;1) in a patient with congenital leukemia.

Q- and C-banded karyotypes of leukemic cells of a patient with congenital acute lymphoblastic leukemia showed the karyotype: 46,XX,ins(6;1)(p21;p13p36). This rearrangement is unusual, and the breakpoints on chromosome 1 are interestingly close to known cellular oncogenes (N-ras, fgr, src-2) and to a putative antioncogene.

Chromosome Aberrations↗
PubMed1989

Translocation t(9;9)(p13;q34) in Philadelphia-negative chronic myeloid leukemia with breakpoint cluster region rearrangement.

Chromosome analysis showed a t(9;9)(p13;q34) in a patient with chronic myeloid leukemia (CML) without a Philadelphia (Ph) chromosome in all examined cells. Southern blot analysis of leukocyte DNA revealed rearrangement of breakpoint cluster region (bcr) within the 5.8-kb bcr sequences as in Ph-positive CML patients. The findings confirm that the 9q34 and 22q11 bands are always involved in CML independent of the chromosomal evidence. It is suggested that Ph-negative bcr-positive CML may have variant translocations, as in the case of the t(9;9) reported here.

Blotting, Southern↗
PubMed1989

Cytogenetic analysis in essential thrombocythemia at diagnosis and at transformation. A 12-year study.

Between 1979 and 1988, 86 patients with clinical and laboratory findings consistent with essential thrombocythemia (ET) were karyotyped at diagnosis. Four patients showed a Philadelphia chromosome and underwent myeloid blastic crisis 2.5-4.5 years later, strongly suggesting a diagnosis of chronic myeloid leukemia. A partial deletion of 13q was seen in another case evolving to leukemia a few months later. Five cases, with normal karyotypes at diagnosis, developed acute transformation after more than 5 years of chronic phase. Four of them showed unusual clonal karyotype abnormalities involving different chromosomal regions. The numerical abnormalities found were trisomy 22 in one case, and trisomy 8 and 19 in another, while structural changes included partial deletion of 5p, partial deletion of 6q, pericentric inversion of chromosome 12, and partial deletion of 20q. These abnormalities have not been previously reported in ET. This investigation confirms the absence of a specific cytogenetic marker for ET, and the infrequent transformation to acute leukemia, often with chromosomal clonal disorders.

Adult↗
PubMed1989

Molecular analysis of the bcr rearrangement in a case of Ph'-negative blastic crisis of Ph'-positive chronic myelogenous leukemia.

We describe here a patient with Ph'-positive chronic myelogenous leukemia (CML) who developed a Ph'-negative blastic crisis. The blast DNA was analyzed on two different occasions, at the beginning of the blastic phase and at the end, shortly before the patient's death. Although cells from both samples had no Ph' chromosome marker (not even a masked one) we could detect a rearrangement of the bcr gene in the second DNA sample, using a '3'-bcr' probe. The same probe and a '5'-bcr' probe failed to detect any rearranged band in the first DNA sample. No rearrangement was identified at the c-myc and N-ras loci, while a slight c-myc amplification was evident in both DNA samples tested.

Blast Crisis↗
PubMed1989

Isolation and characterization of a K562 cell line resistant to 1-beta-D-arabinofuranosylcytosine-mediated erythroid induction.

The isolation of a K562 cell line, K562(S)R, resistant to 1-beta-D-arabinofuranosylcytosine (ara-C)-mediated erythroid induction, is described. Ara-C (10-50 microM) inhibits cell growth of K562(S)R cells but is not able to activate the program of erythroid induction. This failure is associated with the lack in the increase of accumulation of epsilon-globin and gamma-globin mRNA sequences in ara-C-treated K562(S)R cells. This cell line could be of interest for studies focused on molecular mechanisms of activation of globin genes in K562 cells.

Azacitidine↗
PubMed1988

t(1;7) in acute myeloblastic leukemia following myelodysplastic syndrome (RAEB-T).

A case is described of myelodysplastic syndrome (MDS) refractory anemia type with an excess of blasts in transformation with early leukemic evolution (AML-M1). All bone marrow cells examined showed an unbalanced translocation t(1;7). The karyotype was 45, xy, -21, -7, + der dic t(1;7) (q12;q21). There are reports in the literature of the translocation t(1;7) (p11;p11), which leads to trisomy of the long arms of chromosome #1 and monosomy of the long arms of chromosome #7. In the case here described the breakpoints of the chromosomes involved in the translocation differ from the classic ones: in this case there is trisomy of the region 1q12----1qter and monosomy of the region 7q21----7qter. Some clinical and cytogenetic considerations are suggested.

Adult↗
PubMed1988

Variant Philadelphia translocations in CML: correlation with fragile sites.

Of 175 CML patients studied, 14 variants were found, seven of which are presently described. The breakpoints involved in the translocation, other than 9q34 and 22q11, are 3p21, 5q13, 6p21, 7q22, 10q22, and 11p13. Fragile sites were investigated in some of these patients. In two cases a coincidence between fragile site location and breakpoint of the third chromosome involved in Philadelphia formation was found. This observation suggests that the fragile sites can lead to Ph variants in patients developing CML.

Adult↗
PubMed1988

Competition between recipient and donor cells after bone marrow transplantation for chronic myeloid leukaemia.

The cytogenetic and clinical course of three patients allografted for Ph positive chronic myeloid leukaemia are reported. All patients had a peculiar pattern of relapse. Two out of three patients had donor marrow graft pretreated with monoclonal antibody for graft versus host prevention. The cytogenetic relapse was invariably associated with major morphological changes in the marrow indicating that these were also haematological relapses. However, no changes in the peripheral blood count were observed. When relapse occurred in these patients, Ph positive marrow metaphases and host red blood cells ranged from 75% to 100% of the total cell population: thereafter they spontaneously reverted to complete chimaerism. Therefore the presence of leukaemic cells even in considerable amount was not sufficient, per se, to prevail over normal marrow. In addition these observations indicate that relapse was not associated with elimination of the graft: while haemopoiesis was entirely of recipient origin the donor normal stem cells were present and vital although functionally silent. These data suggest that, although TBI remains the more effective tool for eradicating the majority of leukaemic cells, haemopoietic competition between host and donor marrow may have a major impact on leukaemic relapse.

Acute Disease↗
PubMed1988

Relapse after allogeneic bone marrow transplantation for Philadelphia chromosome positive chronic myeloid leukemia: cytogenetic analysis of 24 patients.

One hundred patients with chronic myeloid leukemia (CML) submitted to bone marrow transplantation (BMT) were included in a cooperative cytogenetic study. Relapse (defined on the basis of hematological and cytogenetic findings) occurred in 24 (24%) patients at different intervals after BMT. In 18 of these patients (studied on average 3.3 times between BMT and relapse) no Ph-positive metaphases were detected before relapse. Sixteen (75%) of the patients relapsed with the same chromosomal pattern as that seen before BMT; eight patients, of whom five relapsed in blast crisis, showed additional chromosomal abnormalities resembling those seen in non-transplanted patients. One of these patients relapsed in cells of donor origin. After recognition of relapse, various hematological and cytogenetic patterns were observed. Four patients showed spontaneous reversion to normal (donor-type) chromosomes and hematology. Two other patients were followed for prolonged periods with hypercellular marrows with more than 50% Ph-positive cells but with normal peripheral blood values. The majority of patients proceeded to clinical relapse and required treatment with chemotherapy. We conclude that the isolated finding of a minority of Ph-positive metaphases after BMT should not be classified as relapse; for patients who do relapse, the sequence of cytogenetic and hematological events thereafter is variable.

Adolescent↗
PubMed1987

Karyotype evolution in CML: high frequency of translocations other than the Ph.

The karyotypes of 33 Philadelphia-positive chronic myelogenous leukemia patients during the blastic phase are reported. Only three patients (9%) had a Philadelphia clone without further chromosomal aberrations, whereas, all the others had karyotype evolution. Aside from some nonrandom abnormalities (+8, i(17q), +Ph, +19) we found a higher frequency of clones with random structural rearrangements (13 cases, 39.4%) than previously reported. From a clinical point of view, however, the additional chromosomal (structural) abnormalities do not significantly influence the patients' survival.

Adolescent↗
PubMed1987

Correlation between acquired pseudo-Pelger-Huet anomaly and involvement of chromosome 17 in chronic myeloid leukemia.

Acquired pseudo-Pelger-Huet neutrophils appeared in the peripheral blood of 11 of 83 Philadelphia-positive chronic myeloid leukemia patients during the blastic phase of the disease. Chromosomal analysis performed at the time of pseudo-Pelger appearance showed karyotype evolution with involvement of the short arms of a chromosome #17. In eight cases an i(17q) was present, in two cases an unbalanced translocation, and in one case monosomy. All these rearrangements had in common the loss of the distal end of the short arm. The morphologic and chromosomal study of the remaining 72 chronic myeloid leukemia patients demonstrated neither pseudo-Pelger nor 17p involvement.

Chromosome Aberrations↗