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Biomedical subjects

E Wattel

Publications and source records attributed to E Wattel.

At least 55 records · Page 3Linked to original sources

p16 gene homozygous deletions in acute lymphoblastic leukemia.

The p16 protein is a cyclin inhibitor encoded by a gene located in 9p21, which may have antioncogenic properties, and is inactivated by homozygous p16 gene deletion or, less often, point mutation in several types of solid tumors often associated to cytogenetic evidence of 9p21 deletion. We looked for homozygous deletion and point mutation of the p16 gene in acute lymphoblastic leukemia (ALL), where 9p21 deletion or rearrangement are also nonrandom cytogenetic findings. Other hematologic malignancies including acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), chronic lymphocytic leukemia (CLL), and myeloma were also studied. Homozygous deletion of the p16 gene was seen in 9 of the 63 (14%) ALL analyzed, including 6/39 precursor B-ALL, 3/12 T-ALL, and 0/12 Burkitt's ALL. Three of the 7 ALL with 9p rearrangement (including 3 of the 5 patients where this rearrangement was clearly associated to 9p21 monosomy) had homozygous deletion compared to 5 of the 55 patients with normal 9p (the last patient with homozygous deletion was not successfully karyotyped). Single stranded conformation polymorphism analysis of exons 1 and 2 of the p16 gene was performed in 88 cases of ALL, including the 63 patients analyzed by Southern blot. Twenty-six of the cases had 9p rearrangement, associated to 9p21 monosomy in at least 12 cases. A missense point mutation, at codon 49 (nucleotide 164), was seen in only 1 of the 88 patients. No homozygous deletion and no point mutation of the p16 gene was seen in AML, MDS, CLL, and myeloma. Homozygous deletion of interferon alpha genes (situated close to p16 gene in 9p21) was seen in only 3 of the 9 ALL patients with p16 gene homozygous deletion, and none of the ALL without p16 gene homozygous deletion. Our findings suggest that homozygous deletion of the p16 gene is seen in about 15% of ALL cases, is not restricted to cases with cytogenetically detectable 9p deletion, and could have a pathogenetic role in this malignancy. On the other hand, p16 point mutations are very rare in ALL, and we found no p16 homozygous deletions or mutations in the other hematologic malignancies studied.

Base Sequence↗

Comparison of technetium-99m methoxyisobutylisonitrile and gallium-67 citrate scanning in the assessment of lymphomas.

The aim of this study was to compare the value of scintigraphy using technetium-99m methoxyisobutylisonitrile (MIBI) with that of scintigraphy using gallium-67 citrate in the assessment of Hodgkin's disease and non-Hodgkin's lymphoma and to relate these results with those of CT scan and MRI. Fifty-eight patients were included either for a follow-up examination or for monitoring of their treatment. Twenty-three residual masses were studied. A whole-body scan was performed, followed by single-photon emission computed tomography (SPET) 20 min after injection of 740 MBq of 99mTc-MIBI and 72 h after injection of 185 MBq of 67Ga citrate. The overall sensitivity of 99mTc-MIBI and 67Ga citrate was 71% and 68%, respectively, and the overall specificity was 76% and 44%, respectively. For residual masses, the sensitivity was 44% with both tracers and the specificity was 80% with 99mTc-MIBI and 53% with 67Ga citrate. The positive predictive values were 85% and 68% and the negative predictive values were 59% and 44%, respectively. The signal-to-background ratio was 1.5 for 99mTc-MIBI and 2 for 67Ga citrate. At present, 99mTc-MIBI cannot replace 67Ga citrate in the assessment of lymphomas.

Adult↗

Adolescent growth changes in soft tissue profile.

Growth of the lips, nose and chin was studied in a mixed longitudinal sample of 82 subjects from the "Nijmegen Growth Study". The age range was between 9 and 14 years with a single measurement at the age of 22 years. Differences in growth pattern between boys and girls are illustrated by mean cumulative growth curves and mean growth velocity curves as well as by contour plots.

Adolescent↗

Clonal expansion of human T-cell leukemia virus type I-infected cells in asymptomatic and symptomatic carriers without malignancy.

Human T-cell leukemia virus type I (HTLV-I) is associated with adult T-cell leukemia/lymphoma and tropical spastic paraparesis/HTLV-associated myelopathy. Both diseases are usually preceded by a long clinically asymptomatic period. PCR amplification of the HTLV-I proviral integration sites shows that clonal expansion of HTLV-I-bearing T cells, rather than being an occasional phenomenon in nonmalignant disease, is the norm for both symptomatic and asymptomatic carriers. Sequencing of 100 molecular clones derived by PCR amplification of part of the envelope gene from two asymptomatic carriers revealed almost no genetic variation. Viral amplification via clonal expansion, rather than by reverse transcription, would explain this remarkable genetic stability.

Adult↗

Clinical significance of p53 mutations in newly diagnosed Burkitt's lymphoma and acute lymphoblastic leukemia: a report of 48 cases.

PURPOSE: To correlate the presence of p53 mutations and initial characteristics, response to chemotherapy, and survival in newly diagnosed Burkitt's lymphoma (BL) and Burkitt's acute lymphoblastic leukemia (L3 ALL). PATIENTS AND METHODS: Forty-eight patients with newly diagnosed BL or L3 ALL, most of whom were treated with very intensive regimens, including early CNS disease treatment, were studied. Detection of p53 mutations was made by single-strand conformation polymorphism (SSCP) analysis of exons 5 to 8 of the gene, and mutations were determined by direct sequencing of exons with abnormal SSCP findings. Comparison of outcome between mutated and nonmutated cases was made in all patients and also after excluding five patients who received therapeutic regimens considered as suboptimal and one patient who died of AIDS while in complete remission (CR), as those six patients had no p53 mutations. RESULTS: A point mutation was found in nine patients (19%), and consisted of a missense mutation in seven and a chain-terminating mutation in two. SSCP, sequence, and cytogenetic analysis strongly suggested that eight of nine patients with mutations had retained the normal p53 allele, which had been lost in the remaining patient. These findings were confirmed by fluorescence-in-situ hybridization (FISH) with a p53-specific probe in two patients, including the one who had lost the normal p53 allele. Unexpectedly, mutations were significantly less frequent in patients with disseminated disease, ie, L3 ALL or stage IV BL (four of 35, 11%), than in more localized forms, ie, BL stage I, II, or III (five of 13, 38%) (P = .03). CR rates were similar in mutated (78%) and nonmutated cases (78%). The actuarial disease-free interval (DFI) after 12 months and actuarial survival rates after 24 months were 49% and 66%, respectively, in patients with mutations, and 73% and 48%, respectively, those without mutations. The differences were not significant. CONCLUSION: Our findings suggest that, contrary to what is seen in most other neoplasias, p53 mutations in newly diagnosed BL and L3 ALL are not associated with extensive tumor mass or poor response to intensive therapeutic regimens. It is hypothesized that this difference with most tumors could be due to the fact that p53 mutations in BL and L3 ALL are generally associated with persistence of a normal residual p53 allele, contrary to what is observed in the majority of tumors.

Actuarial Analysis↗

Good predictive value of combined cytogenetic and molecular follow up in chronic myelogenous leukemia after non T-cell depleted allogeneic bone marrow transplantation: a report on 38 consecutive cases.

We prospectively performed repeated cytogenetic and PCR monitoring of residual disease in all cases Ph positive of chronic myeloid leukemia (CML) allografted with non T cell depleted marrow at our institution over a period of 8 years. Thirty eight patients who survived the immediate post transplant period could be analyzed (median of 3 cytogenetic analyses/patient, examining 100 mitoses, and 4 PCR analyses/patient). Seven of the 38 patients had a hematological relapse (which was extramedullary in one case) and one a purely cytogenetic relapse, possibly stabilised by interferon treatment. Within 6 months of transplant, Ph positive mitoses were seen in 2 patients, and positive PCR in most cases, without implying subsequent relapse. Six of the 32 patients analyzed cytogenetically more than 6 months post transplant had Ph positive mitoses on at least one occasion: 5 had a hematological relapse within 7 months of positive cytogenetic analysis, and the remaining patient, treated by interferon remained in purely cytogenetic relapse. (The extramedullary relapse was not preceded by a positive marrow karyotype). Eight of the 38 patients had positive PCR findings on at least one occasion more than 6 months post transplant. Seven relapsed (6 hematological relapses including the extramedullary relapse, and 1 cytogenetic relapse) after 3 to 20 months, but the remaining patient remained in CR 36 months later, with negative PCR. The 30 patients who never had positive PCR findings remained in CR. In this relatively large series of patients, we found a good correlation between PCR findings more than 6 months post transplant and remission or relapse status.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Glomerular injury in chronic myelomonocytic leukemia.

Among 825 cases of de novo myelodysplastic syndromes (MDS) diagnosed over a period of 13 years in our center, 4 had clinically significant glomerulopathy. All 4 fulfilled diagnostic criteria of chronic myelomonocytic leukemia (CMML), and could be classified in the low or intermediate risk groups according to two scoring systems. Presenting symptoms of renal involvement were edema in 3 cases and acute renal failure in the remaining patient. Three patients had the nephrotic syndrome. Renal biopsy (performed in 2 cases but considered as contraindicated in the other cases) showed AL amyloidosis on one case and extracapillary glomerulonephritis in the other case. The 4 patients were treated with V16 or hydroxyurea and two had renal improvement. Only one previous case of MDS associated with glomerulopathy has been reported before and also very probably had CMML. This, and the response of renal disease to chemotherapy in 2 of our patients suggests a possible relationship between the two disorders. More systematic investigation of glomerular function, in CMML, could possibly disclose a higher incidence of cases of glomerular injury in this type of MDS.

Aged↗

Expression of the multidrug resistance P glycoprotein in newly diagnosed adult acute lymphoblastic leukemia: absence of correlation with response to treatment.

We analyzed P glycoprotein (PGP) expression and its correlation with hematological parameters and outcome in 50 cases of newly diagnosed adult acute lymphoblastic leukemia (ALL). PGP expression was evaluated by flow cytometry using MRK16 monoclonal antibody (MoAb) and/or immunocytochemistry on marrow slides, using JSB1 MoAb. Thirty-two of the 50 patients (64%) were PGP positive by at least one of the two methods, which gave concordant results in 15 of the 18 cases in which they were both used. No correlation between PGP expression and clinical and hematological parameters including WBC counts, immunophenotype and karyotype was seen, although there was a trend for more frequent CD34 expression in PGP-positive cases. All patients were treated with intensive chemotherapy. We found no difference in complete remission (CR) rate, actuarial disease-free survival and survival in PGP-positive and PGP-negative cases. Our findings suggest that the clinical significance of PGP expression is less clear in ALL than in AML. Wider use of functional techniques of evaluation of mdr1 gene expression, which assess the 'pumping' activity of PGP, and their correlation with quantitative analysis of mdr1 mRNA and protein, would probably improve knowledge of the role of PGP in ALL. Analysis of other mechanisms of drug resistance, especially multidrug resistance-associated protein (MRP) expression, would also be useful.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

Association of myelodysplastic syndrome and relapsing polychondritis: further evidence.

We report five patients with both a myelodysplastic syndrome (MDS) and relapsing polychondritis (RP), that represented 0.6% of all MDS and 28% of all RP diagnosed over a period of 14 years. Ten other cases had previously been reported (four in detail), supporting a non-fortuitous association between the two disorders, already suggested for MDS and some other immunological disorders.

Adult↗

Myelodysplastic syndromes and acute myeloid leukemia with 17p deletion. An entity characterized by specific dysgranulopoïesis and a high incidence of P53 mutations.

We looked for correlations between cytogenetic rearrangements leading to 17p deletion and presence of dysgranulopoïesis and p53 mutations in MDS and AML. Forty-nine (4.3%) of the MDS and AML studied cytogenetically at our institution over a period of 11 years had detectable 17p deletion, through monosomy 17 (14 cases) or rearrangements of chromosome 17 (generally unbalanced translocations between 17p and another chromosome) (35 cases). Most of the patients had additional complex cytogenetic findings, and 10 cases were therapy related. In 70% of the patients with 17p deletion, a particular type of dysgranulopoïesis, combining pseudo-Pelger-Huët anomaly and small vacuolated neutrophils was seen in > 5% marrow neutrophils, whereas 69% of the patients had a p53 mutation, generally in a missense mutation involving exons 5 to 8 of the p53 gene. FISH analysis, performed in eight cases, confirmed loss of one P53 allele in all of them. No DNA fragmentation suggesting increased apoptosis was found in marrow samples. Response to chemotherapy was almost uniformly poor and median survival was only 3 months. Analysis of dysgranulopoïesis and p53 mutations were also made in 'control' groups of MDS and AML without 17p deletion. 'Typical' dysgranulopoïesis, combining pseudo-Pelger-Huët anomaly and small vacuolated neutrophils in > 5% marrow neutrophils, was not seen in any of the 47 MDS and AML without 17p deletion analyzed and without p53 mutation (P = 10(-4) with patients having 17p deletion), and was seen in one of five patients without 17p deletion but with a p53 mutation. Only 3.1% of 256 MDS and AML without 17p deletion had a p53 mutation (P = 10(-4) with patients having 17p deletion). These findings suggest that 17p deletion, in MDS and AML, is strongly correlated to the presence of a particular type of dysgranulopoïesis and to a high incidence of p53 mutations, and that MDS and AML with 17p deletion could constitute a new morphological-cytogenetic-molecular entity in myeloid disorders.

Acute Disease↗

p53 mutations are associated with resistance to chemotherapy and short survival in hematologic malignancies.

We analyzed the prognostic value of p53 mutations for response to chemotherapy and survival in acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), and chronic lymphocytic leukemia (CLL). Mutations were detected by single-stranded conformation polymorphism (SSCP) analysis of exons 4 to 10 of the P53 gene, and confirmed by direct sequencing. A p53 mutation was found in 16 of 107 (15%) AML, 20 of 182 (11%) MDS, and 9 of 81 (11%) CLL tested. In AML, three of nine (33%) mutated cases and 66 of 81 (81%) nonmutated cases treated with intensive chemotherapy achieved complete remission (CR) (P = .005) and none of five mutated cases and three of six nonmutated cases treated by low-dose Ara C achieved CR or partial remission (PR) (P = .06). Median actuarial survival was 2.5 months in mutated cases, and 15 months in nonmutated cases (P < 10(-5)). In the MDS patients who received chemotherapy (intensive chemotherapy or low-dose Ara C), 1 of 13 (8%) mutated cases and 23 of 38 (60%) nonmutated cases achieved CR or PR (P = .004), and median actuarial survival was 2.5 and 13.5 months, respectively (P < 10(-5)). In all MDS cases (treated and untreated), the survival difference between mutated cases and nonmutated cases was also highly significant. In CLL, 1 of 8 (12.5%) mutated cases treated by chemotherapy (chlorambucil and/or CHOP and/or fludarabine) responded, as compared with 29 of 36 (80%) nonmutated cases (P = .02). In all CLL cases, survival from p53 analysis was significantly shorter in mutated cases (median 7 months) than in nonmutated cases (median not reached) (P < 10(-5)). In 35 of the 45 mutated cases of AML, MDS, and CLL, cytogenetic analysis or SSCP and sequence findings showed loss of the nonmutated P53 allele. Our findings show that p53 mutations are a strong prognostic indicator of response to chemotherapy and survival in AML, MDS, and CLL. The usual association of p53 mutations to loss of the nonmutated P53 allele, in those disorders, ie, to absence of normal p53 in tumor cells, suggests that p53 mutations could induce drug resistance, at least in part, by interfering with normal apoptotic pathways in tumor cells.

Adult↗

Inv(16) may be one of the only 'favorable' factors in acute myeloid leukemia: a report on 19 cases with prolonged follow-up.

We report our experience of treatment of acute myeloid leukemia (AML) with inv(16). Nineteen of 531 (3.6%) cases of newly diagnosed AML karyotyped over a 12 year period had inv(16)(p13q22) and none had t(16;16) or del 16q. Morphologically, all patients had M4eo. All patients were treated with conventional anthracycline-Ara-C chemotherapy, followed by moderate or more intensive consolidation chemotherapy. All patients received central nervous system (CNS) prophylaxis with intrathecal methotrexate and Ara-C, and cranial irradiation. Eighteen patients (95%) achieved complete remission (CR). Three had a bone marrow relapse, one had a CNS relapse and 14 patients remained in first CR, 11 of them with a follow-up greater than 44 months. Disease-free survival was 74% after 10 months, and actuarial survival 88% after 4 years, and 62% after 6 years. No other AML subgroup, in our experience, had a long-term survival approaching that of AML with inv(16) (although similar favorable outcome may be anticipated in acute promyelocytic leukemia treated by a combination of retinoic acid and chemotherapy).

Acute Disease↗

A randomized trial comparing vinblastine in slow infusion and by bolus i.v. injection in idiopathic thrombocytopenic purpura: a report on 42 patients.

Forty-two patients with ITP were randomly allocated to vinblastine slow infusion or bolus injection. 16/21 patients (76%) receiving slow infusion of vinblastine and 14/21 patients (67%) receiving a bolus injection of vinblastine had a response. There was no superiority of slow infusions of vinblastine over intravenous bolus injections, either when recently diagnosed and chronic ITP were analysed together or separately. In our opinion, intravenous bolus injections of vinblastine might be preferred, because they are easier to perform and have a better local tolerance.

Adolescent↗

Androgen therapy in myelodysplastic syndromes with thrombocytopenia: a report on 20 cases.

Twenty patients with myelodysplastic syndromes (MDS) and (i) platelets < 50 x 10(9)/l and (ii) bone marrow blasts < or = 10% were treated with androgen therapy (fluoxymesterone at 1 mg/kg/d: seven patients; danazol at 600 mg/d: 13 patients) for at least 3 months. 11 of them (55%) had an increase in platelet counts by at least 30 x 10(9)/l and a disappearance of bleeding symptoms was seen in 6/6 patients with initial bleeding. A response with neutrophil counts (six cases) or haemoglobin levels (five cases) was less often seen. Treatment was continued for 3+ to 27 months in responders (the dose being reduced by 50% after 6 months). Seven patients on maintenance treatment were still responding. Another patient died while he was still responding, and the remaining three patients relapsed after discontinuation (two cases) and dose reduction to 50% (one case) of the androgen used. Side-effects of treatment were moderate. In our experience, androgen therapy can be useful in patients with 'low risks' MDS (i.e. with marrow blasts < or = 10%) and severe thrombocytopenia, especially because no growth factor regularly active on platelets is currently available.

Adult↗

Treatment with very low-dose GM-CSF in myelodysplastic syndromes with neutropenia. A report on 28 cases.

We treated 28 cases of myelodysplastic syndrome (MDS) with neutropenia by very low-dose GM-CSF (0.25 or 0.5 micrograms/kg/day). Median age was 69 years. Nine patients had RA, 18 had RAEB, and one had RARS. Eighteen patients had absolute neutrophil counts (ANC) < or = 0.5 x 10(9)/l, and ten had ANC between 0.5 and 1.0 x 10(9)/l. Ten patients had experienced > or = WHO grade II infection(s) during the preceding 3 months. Eighteen patients (64%) had a response (i.e. ANC at least doubled and > or = 1 x 10(9)/l after 1 month), including 4/8 patients treated at 0.25 mu/kg/day, and 14/20 treated at 0.5 microgram/kg/day (difference not significant). Two of the non-responders obtained a response after dose escalation to 0.5 and 1 microgram/kg/day, respectively. The only prognostic factor of response was FAB subtype (10/11 responses in patients with RA or RARS, vs. 8/17 in RAEB, p = 0.04). Patients with ANC < or = 0.5 x 10(9)/l had a 55% (10/18) response rate, which was not significantly lower than the 80% (8/10) response rate observed in patients with ANC > 0.5 x 10(9)/l. Side-effects were generally moderate, except in three patients where the drug had to be discontinued, including the only patient who progressed to AML. In responders, GM-CSF was continued during 2 to 14 months (median 6), and the response persisted in all but one case, who relapsed after 60 days of treatment. During follow-up, only one responder had > or = WHO grade II infections, as compared to five of the non-responders (of whom two had fatal infectious episodes). In conclusion, very low-dose GM-CSF can durably increase ANC in about two thirds of MDS with neutropenia. Although it remains to be shown in randomized trials that it can reduce the incidence of infections and improve survival in MDS, very low-dose GM-CSF may be an interesting approach in MDS, associated to reasonable cost.

Aged↗