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J A Child

Publications and source records attributed to J A Child.

At least 37 records · Page 2Linked to original sources
PubMed1999

FICTION-TSA analysis of the B-cell compartment in myeloma shows no significant expansion of myeloma precursor cells.

Studies utilizing flow cytometry and PCR have shown that the B-cell compartment in myeloma contains cells which are clonally related to the myelomatous plasma cells. Current data, however, remains inconclusive regarding the extent of this involvement. By combining fluorescent immunophenotyping, tyramine signal amplification and fluorescence in-situ hybridization (FICTION-TSA), we have used the presence of numerical chromosomal abnormalities within plasma cells as a clonal marker to examine the CD20+ B-cell compartment for the presence of aneuploidy. A series of 54 cases of myeloma were screened for the presence of numerical abnormalities of chromosomes 3 and 11. FICTION-TSA was performed on 13 cases with either trisomy 3 or 11 and on a control group of six cases known to be disomic for the two chromosomes. B-cell numbers were reduced in the myeloma cases compared to the normal controls (median 1.8% v 3.0%, P = 0.05). In the cases with a chromosomal marker, three signals were seen in a median of 1.88% of CD20+ B cells compared to 2.58% within the control group. Comparison of the two groups using a Wilcoxon-Mann-Whitney U test showed no statistical significant difference. Using this data set, it was possible to exclude a 3.03% expansion of clonally related B cells (95% confidence level). We conclude that the B-cell compartment in myeloma does not represent the major site of clonal expansion, and if clonally related cells are present then the numbers are few.

Aneuploidy↗
PubMed1998

Liposomal daunorubicin: in vitro and in vivo efficacy in multiple myeloma.

Liposomal encapsulation of anthracyclines is a potential method of drug targeting, altering both the antitumour activity and side-effect profile of anthracyclines. Liposomal daunorubicin (daunoxome) shows both altered pharmacokinetics and a potential for reducing dose-limiting cardiotoxicity compared to conventional daunorubicin. Anthracyclines have a common role in the treatment of multiple myeloma, a prevalent and fatal haematological malignancy. Avoiding cumulative anthracycline toxicity in these patients is important. There is also a need for more effective relapse schedules given that many patients have chemosensitive disease at relapse. We have analysed daunoxome in vitro in myeloma cell lines using a thymidine-based cytotoxicity assay and show superior efficacy compared to a pegylated liposomal doxorubicin derivative. Subsequently we have treated seven relapsed myeloma patients with a regime consisting of oral CCNU 25-50 mg/m2 on day 1, 4 days of oral dexamethasone 10 mg/m2 and intravenous daunoxome (liposomal daunorubicin) given for 4 days (total 100 mg/m2). The main toxicity was myelosuppression but non-haematological toxicity was minimal and the regime was well tolerated. Four out of seven of these heavily pretreated patients responded. Together with the in vitro data on its cytotoxicity in myeloma and its favourable pharmacokinetic profile further studies of liposomal daunorubicin in myeloma would be warranted.

Aged↗
PubMed1998

Phase I/II evaluation of pentostatin (2'-deoxycoformycin) in a five day schedule for the treatment of relapsed/refractory B-cell chronic lymphocytic leukaemia.

The purpose of this study was to determine the efficacy and toxicity of pentostatin (2'-deoxycoformycin) administered in a five day schedule every 28 days to patients with B-cell chronic lymphocytic leukaemia (B-CLL) relapsed from or refractory to at least one line of prior chemotherapy. The initial dose level of 2 mg/m2/day was adjusted up or down by 0.5 mg/m2 in subsequent cycles on the basis of haematological and non-haematological toxicities. The five day schedule was selected because published pharmacokinetic studies had indicated that although pentostatin had an elimination half-life of approximately six hours and could inhibit plasma adenosine deaminase activity for 24 hours, recovery of enzyme activity rapidly took place and accumulation of dATP which has a toxic effect on non-replicating lymphoid cells could be increased by repeated dosing. Twenty-nine patients were entered into the study and dose-escalation was possible in nine, while dose reductions were required for five patients. Of the 24 patients evaluable for response, complete responses were achieved in two and partial responses in five for an overall response rate of 29.2%. Toxicity consisted of myelosuppression, infection, nausea and vomiting and hepatotoxicity but was experienced at acceptable levels considering the heavily pre-treated nature of the patient population. Pentostatin in this schedule has salvage activity in previously treated or resistant patients with B-CLL.

Adult↗
PubMed1998

Five-year follow-up of a prospective randomised multi-centre trial of weekly chemotherapy (CAPOMEt) versus cyclical chemotherapy (CHOP-Mtx) in the treatment of aggressive non-Hodgkin's lymphoma. Central Lymphoma Group.

BACKGROUND: Weekly alternating regimen known as CAPOMEt is compared to standard cyclical chemotherapy (CHOP-Mtx) in aggressive non-Hodgkin's lymphoma (NHL). PATIENTS AND METHODS: Three hundred and eighty-one patients with aggressive NHL were randomised to receive either cyclophosphamide, doxorubicin, vincristine, prednisone and methotrexate (CHOP-Mtx) on a cyclical basis or a weekly regimen incorporating the same drugs with the addition of etoposide (CAPOMEt). RESULTS: After pathological review, 281 patients were deemed eligible. At the census date of 31 March 1994, 158 patients were alive with a median follow up of 5.9 years (minimum 3.0 years). Analysis of all patients and eligible patients showed no significant treatment differences in the rates of complete remission (CR), failure free survival (FFS) or overall survival (OS) between the two arms. The actuarial median OS was 24 months for CAPOMEt compared with 31 months for CHOP-Mtx, with five-year actuarial survival rates of 37% and 43%, respectively. Myelosuppression was significantly more severe with CHOP-Mtx and neurotoxicity was much more common with CAPOMEt. CONCLUSION: Weekly CAPOMEt is equally effective as standard cyclical CHOP-Mtx treatment in aggressive NHL.

Adolescent↗
PubMed1998

B-lymphocyte suppression in multiple myeloma is a reversible phenomenon specific to normal B-cell progenitors and plasma cell precursors.

The reduced levels of normal immunoglobulin in patients with myeloma may be due to suppression of normal B-cell differentiation. However, reports on the numbers of B cells vary, with some finding decreases consistent with immunoparesis, and others reporting expansions of phenotypically aberrant cells. We have therefore assessed the phenotype and levels of B lymphocytes in patients at presentation (n = 23), in plateau or complete remission (PB n = 42, BM n = 18), and in relapse (PB n = 17, BM n = 14), in comparison to normal individuals (n = 10). Phenotypic analysis was performed using five-parameter flow cytometry, with CD14 used to exclude monocytes where necessary. We found no evidence of a phenotypically distinctive blood or marrow B-cell population in patients with myeloma, nor of an increase in the levels of any B-cell subset. Numbers of blood CD19+ 38+ normal plasma cell precursors were significantly reduced in presentation/relapse patients, but not in patients in plateau/remission. Total CD19+ cells were significantly reduced only in patients with circulating myeloma cells, detected by IgH-PCR. In the marrow, CD19+ B cells expressing CD5, CD10, CD34, CD38, CD45(low) and Syndecan-1 were significantly decreased at presentation/relapse, but not in patients in plateau/remission. The majority of these antigens are expressed by normal B-cell progenitors, indicating that myeloma also affects the early stages of B-cell development. The suppression of progenitor cells was not restricted to B-lymphoid differentiation, as total CD34+ cells were also significantly reduced in the marrow of myeloma patients at presentation. These results indicate that, if neoplastic B cells are present in myeloma, they are low in number and have a phenotype similar to their normal counterparts. Furthermore, there is a reversible suppression of CD19+ B lymphocytes that correlates inversely with disease stage, and specifically affects the early and late stages of normal B-cell differentiation.

Adult↗
PubMed1997

Detection and quantitation of the CBFbeta/MYH11 transcripts associated with the inv(16) in presentation and follow-up samples from patients with AML.

We have developed a competitor-based RT-PCR technique which will detect and quantitate the CBFbeta/MYH11 transcripts associated with inv(16)(q22;p13) and have used it to study presentation and follow-up samples of acute myeloid leukaemia (AML). The levels of the leukaemia-specific transcripts are expressed as a ratio to a ubiquitously expressed mRNA species (Abl) which controls for RNA degradation. This technique has been applied to 75 consecutive patients presenting with either de novo AML or tMDS; 6/75 patients analysed were positive for the inv(16), all were confirmed by conventional cytogenetics. The inv(16) has a strong association with M4Eo, but we found only 2/6-positive patients to have this diagnosis (two patients with M2, one patient M1 and one patient had MDS). At presentation the levels of CBFbeta/MYH11 transcripts were 0.1-10/Abl transcript (mean 3.3/Abl transcript). Seventeen follow-up samples were available on 5/6 of these patients, and on two further patients in whom stored material was available. Following the first cycle of chemotherapy the level of transcripts was at least 10(-2) lower (0.1-10 x 10(-2)/abl transcript) than their presentation sample. Subsequent samples on these patients when in remission gave transcript levels in the range (1.0 x 10(-4) - 2 x 10(-3)/abl transcript), and three long-term follow-up samples were negative. We have developed a quantitative test which opens the possibility of predicting relapse by detecting changes in the numbers of leukaemia-specific transcripts.

Acute Disease↗
PubMed1997

Circulating plasma cells in multiple myeloma: characterization and correlation with disease stage.

The aim of this study was to develop a flow cytometric test to quantitate low levels of circulating myeloma plasma cells, and to determine the relationship of these cells with disease stage. Cells were characterized using five-parameter flow cytometric analysis with a panel of antibodies, and results were evaluated by comparison with fluorescent consensus-primer IgH-PCR. Bone marrow myeloma plasma cells, defined by high CD38 and Syndecan-1 expression, did not express CD10, 23, 30, 34 or 45RO, and demonstrated weak expression of CD37 and CD45. 65% of patients had CD19- 56+ plasma cells, 30% CD19- 56(low), and 5% CD19+ 56+, and these two antigens discriminated myeloma from normal plasma cells, which were all CD19+ 56(low). Peripheral blood myeloma plasma cells had the same composite phenotype, but expressed significantly lower levels of CD56 and Syndecan-1, and were detected in 75% (38/51) of patients at presentation, 92% (11/12) of patients in relapse, and 40% (4/10) of stem cell harvests. Circulating plasma cells were not detectable in patients in CR (n = 9) or normals (n = 10), at a sensitivity of up to 1 in 10,000 cells. There was good correlation between the flow cytometric test and IgH-PCR results: myeloma plasma cells were detectable by flow cytometry in all PCR positive samples, and samples with no detectable myeloma plasma cells were PCR negative. Absolute numbers decreased in patients responding to treatment, remained elevated in patients with refractory disease, and increased in patients undergoing relapse. We conclude that flow cytometry can provide an effective aternative to IgH-PCR that will allow quantitative assessment of low levels of residual disease.

Adult↗
PubMed1997

p53 gene mutations in multiple myeloma.

AIM: To assess whether p53 gene mutation is important in the pathogenesis and progression of multiple myeloma. METHODS: Thirty eight DNA samples (derived predominantly from bone marrow) obtained from 31 patients with multiple myeloma were examined for mutations in p53 exons 5-9 by polymerase chain reaction single strand conformation polymorphism. Twenty three samples were analysed at the time of diagnosis (one patient had plasma cell leukaemia), three in plateau phase, and 12 at relapse (one plasma cell leukaemia and one extramedullary relapse). RESULTS: One p53 mutation was detected in this group of patients (3.2%). This was seen in the diagnostic bone marrow sample of a 35 year old man with stage IIA disease and occurred in exon 6 as a result of a silent A to G transition at codon 213 (CGA-->CGG), a polymorphism that has been reported in about 3% of breast and lung tumours. CONCLUSIONS: p53 gene mutations are rare events in multiple myeloma and would seem to be of limited value as a prognostic factor.

Adult↗
PubMed1996

A phase I trial to assess the value of recombinant human granulocyte colony stimulating factor (R-MeTHuG-CSF, filgrastim) in accelerating the dose rate of chemotherapy for intermediate and high-grade non-Hodgkin's lymphoma (NHL). The Central Lymphoma Group.

In a multi-centre phase I study we investigated the possibility of reducing the interval between courses of standard CHOP (cyclophosphamide 750 mg/m2, doxorubicin 50 mg/m2, vincristine 2 mgs day 1, and prednisolone 40 mg/m2 days 1-8) from 21 days to 15 days and then 10 days using granulocyte colony stimulating factor (r-MetHuG-CSF (Amgen)-filgrastim) to accelerate neutrophil recovery. Patients received CHOP followed by G-CSF 5 micrograms/kg s.c. from day 2 to the day before the next course (e.g. days 2-14 for the 15-day interval). A total of 28 patients with newly diagnosed intermediate grade or high grade NHL were studied. Four patients were studied at a 21-day interval, six patients were treated at a 15-day interval and subsequently six patients at a 10-day interval. Following analysis of this initial cohort, a further 12 patients were evaluated; four at the 15-day interval, and eight at the 10-day interval. No dose-limiting toxicity was seen in the four patients receiving 21-day CHOP. Dose-limiting toxicity was seen in 4/10 patients treated at the 15-day interval (M:F 7:3, median age 55.5, range 39-67 years). This consisted of infection in two patients, recurrent infection and debility in a third, and mucositis in a fourth. Seven patients experienced one or more infectious episodes requiring antibiotics (median number of episodes: 2, range 1-4). Fourteen patients (M:F 4:3, median age 47.5, range 25-63 years) were treated at the 10-day interval. Dose-limiting toxicity was seen in six patients. This consisted of severe mucositis in three patients, neutropenia and thrombocytopenia on two separate occasions in one patient, and steroid-induced gastritis in two patients. Nine patients had one or more documented infections (median: 2, range 1-3) requiring antibiotics, of which six were severe (WHO grade 3 or 4). One patient died of Pneumocystis carinii (PCP) pneumonia. In summary, G-CSF (filgrastim) will facilitate the shortening of the dosage interval between cycles of CHOP chemotherapy due to accelerated hematological recovery. However, non-hematological toxicity due to the shorter dosage interval is increased and infective episodes are frequent.

Adult↗
PubMed1996

Microsatellite instability in follicle centre cell lymphoma.

Fluorescent polymerase chain reaction (PCR) was used to assay 12 microsatellite markers (APC x 2, DCC, P53 x 2, RB1, NM23, WT1, D6S260, D6S262, D6S281 and TNFa) to look for evidence of microsatellite instability in 40 cases of follicle centre cell lymphoma (FCC). Evidence of novel alleles seen in the tumour tissue but not the normal uninvolved tissue was seen in seven cases (17%). In only two of these cases (5%) was more than one locus involved but in these cases multiple affected loci were seen (4/12 and 7/12 respectively). The detection of microsatellite instability indicates a DNA repair defect such as that which would be predicted to occur in cells with mutated mismatch repair genes, a novel finding in FCC lymphoma.

Chromosomes, Human, Pair 14↗
PubMed1996

Mobilization of Philadelphia-negative peripheral blood mononuclear cells in chronic myeloid leukaemia using hydroxyurea and G-CSF (filgrastim).

A relatively simple and non-toxic out-patient-based regimen for the mobilization of Philadelphia-negative (Ph-ve) mononuclear cells in chronic myeloid leukaemia (CML) was evaluated in 10 patients, nine in stable chronic phase and one in accelerated phase. They received oral hydroxyurea at a mean dose of 3.5 g/m2 daily for 7 d, followed by 300 micrograms of G-CSF daily until the last day of harvesting. In the nine chronic-phase patients the mean number of days from the end of hydroxyurea to the commencement of harvesting was 14.5 (range 10-18). The patient in accelerated phase recovered and was harvested after 6 d. The mean number of aphereses performed was 3.4. Adequate numbers of stem cells were obtained in 9/10 patients judged by our usual criteria. Side-effects were mild in comparison to published intravenous schedules. No patients lost their hair. Five (50%) patients required admission with neutropenic fever which responded to antibiotics in all cases. Four (40%) patients developed a transient rash and four (40%) experienced mild oral mucostis. This level of toxicity enabled half of the patients to be treated entirely on an out-patient basis. The harvest products were analysed for cells belonging to the leukaemic clone by conventional cytogenetics, FISH and PCR. All were PCR positive. The mean Ph positivities by cytogenetics and FISH were comparable at 18.1% and 15% respectively. Half the patients had > 98% normal metaphases. We conclude that this approach is comparable in efficacy to published intravenous regimens and significantly less toxic. It can be safely used at diagnosis before interferon therapy commences.

Administration, Oral↗
PubMed1996

Assessment of IgH PCR strategies in multiple myeloma.

AIMS: To compare the ability of four commonly used PCR techniques to demonstrate clonal IgH rearrangements in multiple myeloma. METHODS: Bone marrow samples (containing a minimum of 10% plasma cells) were obtained from 127 patients with confirmed multiple myeloma. Framework 3 (Fr3) PCR was performed in all cases and the Framework 1 (Fr1f) PCR, which utilises six VH family specific primers, in 98 cases. In addition, 44 cases were assessed by Fr3, Fr1f, Framework 2 (Fr2) and Framework 1 consensus (Fr1 con) PCR techniques. JH primer selection was also assessed such that each PCR strategy was performed twice in each of the 44 cases, using the JH consensus primer (JH con) alone and then repeated with an equimolar mixture of JH con, JH3 and JH6 (JH mix). RESULTS: Clonal rearrangements were demonstrated in 71 (56%) of 127 cases with the Fr3 PCR and in 52 (53%) of 98 with the Fr1f PCR. However, by using both techniques it was possible to demonstrate clonal IgH rearrangements in 92 (75%) of 122 cases. Forty four cases were assessed by all four PCR techniques; in these cases the Fr3 and Fr1f PCRs demonstrated clonal rearrangements in 26 (59%) cases with a combined yield of 34 (77%). The Fr2 and Fr1 con PCR techniques had inferior pick up rates, demonstrating clonal rearrangements in 21 (48%) of 44 cases and a combined yield of 28 (63%). The Fr2 PCR did, however, demonstrate a clonal rearrangement in one case negative by both Fr3 and Fr1f. Two additional rearrangements were demonstrated by using JH mix; one became positive by Fr3, Fr1f and Fr2 and the other positive by Fr1f, Fr1 con and Fr2. CONCLUSIONS: By utilising both the Fr3 and Fr1f PCR techniques it is possible to demonstrate definitive clonal rearrangements in the majority of patients with multiple myeloma. The Fr1 con and Fr2 PCR techniques have inferior pick up rates but may detect some additional rearrangements.

Bone Marrow Examination↗
PubMed1996

Detection of clonal immunoglobulin gene rearrangements in the peripheral blood progenitor cells of patients with multiple myeloma: the potential role of purging with CD34 positive selection.

Aims-To determine the extent of clonal cell contamination of peripheral blood progenitor cell (PBPC) collections in patients with multiple myeloma (MM) and to assess the purging efficacy of CD34 positive selection.Methods-PBPC collections from 29 patients with MM were analysed for the presence of clonal immunoglobulin heavy chain (IgH) gene rearrangements with a fluorescence based PCR technique. In addition, the PBPC from eight of the 29 patients were "purged" by selection of CD34 positive haematopoietic progenitors with an avidin-biotin immunoabsorption column (Ceprate). In each case the unmanipulated PBPC, CD34 positive and waste fractions were all assessed for the presence of clonal IgH rearrangements.Results-Clonal IgH rearrangements (identical with those demonstrated in diagnostic bone marrow samples) were demonstrated in 10 (35%) of 29 cases and seemed to be confined to those with significant residual bone marrow disease. Clonal rearrangements were evident in the PBPC of two of the eight patients who underwent CD34 selection; in both instances a "clonal purge" was seen as it was not possible to demonstrate the clonal rearrangement in the CD34 positive fraction. In four of the six remaining cases the normal polyclonal fingerprint could not be demonstrated in the CD34 positive fraction, which is consistent with a significant reduction in contaminating B cells.Conclusions-Clonal cells contaminate PBPC collections in a significant proportion of patients with MM and may be eliminated by CD34 positive selection.

Journal Article↗
PubMed1996

Peripheral blood stem cell transplantation in myeloma using CD34 selected cells.

We have performed nine CD34 selection procedures on peripheral blood stem cells harvested from eight patients with myeloma using the Cellpro avidin-biotin immunoaffinity column (Ceprate). They all received CVAMP chemotherapy to maximum response prior to mobilisation. Six of the patients have been transplanted using these cells, one receiving successive autografts. Median absolute cell numbers processed and retrieved were: 31.1 x 10(9) pre-column, 2.07 x 10(8) in the final product and 30.4 x 10(9) in the column waste. Mean CD34 positivity in the product was 49% (range 18.4-98) with a median CD34+ yield of 31.4% (range 21-37.8). IgH PCR was performed and seven of the eight patients were amplifiable. Of these, two were positive in the pre-column product and both of these were successfully purged with a negative result in the final, post-column product. Patients were transplanted with a median of 2.0 x 10(6) CD34+ cells/kg (range 1.5-9.4) following conditioning with melphalan 200 mg/m2. The mean time to recovery of neutrophils to > 0.5 x 10(9)/l and platelets to > 20 x 10(9)/l was 16 and 17 days, respectively. At a mean follow-up of 9 months, four of the six patients transplanted are alive, three of them in complete remission and one in a clinically stable relapse. One has died of disease relapse and one of progressive neurological problems the aetiology of which was uncertain but there was no sign of progression of their myeloma. We conclude that PBSCT using CD34 selected cells is safe and practical in myeloma following remission induction with CVAMP chemotherapy.

Antigens, CD34↗
PubMed1995

Heterogeneity in cell proliferation and expression of p53 and bcl-2 during the indolent phase of germinal centre cell lymphoma: an explanation for clinical variability.

Germinal centre cell lymphomas (GCCL) show a wide range of clinical outcomes from persistent indolent disease to large cell transformation. To investigate possible mechanisms of this heterogeneity, a combined morphometric and immunohistological study of p53, bcl-2 and cell proliferation was carried out. There was wide variation in p53 expression between biopsies and between individual follicles in the same tumour. A similar pattern of variation was seen using the cell-cycle marker MIB1, but this did not correlate with p53 expression. Even in cases in which a t(14;18) was demonstrated by PCR, variation occurred in the number of cells expressing bcl-2. On the basis of these results, we suggest that the probability of the clonal expansion of GCCL tumour cells carrying additional genetic abnormalities depends on a complex interaction of cell proliferation with p53 and bcl-2 expression, and that this may account for variation seen in the clinical behaviour seen in this group of tumours.

Antibodies, Monoclonal↗
PubMed1995

Detection of clonal immunoglobulin gene rearrangements in the PBPC harvests of patients with acute lymphoblastic leukaemia.

We have used a fluorescently based PCR technique to detect rearrangements in the immunoglobulin heavy chain (IgH) gene in the presentation BM of five patients with adult ALL and have looked for similar rearrangements in their PBPC. Using this approach we have been able to demonstrate clonal rearrangements in the PBPC of two of five patients. Remission BM samples taken 6-12 weeks prior to leucapheresis failed to show a clonal rearrangement in either patient. The significance of these results is discussed.

Base Sequence↗