Expression of AC133 and CD117 on candidate normal stem cell populations in childhood B-cell precursor acute lymphoblastic leukaemia

To identify residual candidate normal progenitor/stem cell populations in childhood B-cell precursor acute lymphoblastic leukaemia (ALL), expression of AC133 and CD117 was analysed on the leukaemic cell clone and on immature B-lineage-negative CD34+CD19- bone marrow cells. 10/25 patients (40%) had no detectable expression of AC133 within the leukaemic cell clone. 24/26 patients (92%) lacked expression of CD117 on the leukaemic blast cell population. In contrast, a distinct AC133-positive cell population was found in 8/8 children with AC133-negative ALL and a CD117-positive cell population could be identified in 12/12 children with CD117-negative ALL, within the CD34+CD19- progenitor/stem cell compartment. These observations provide further evidence that in B-cell precursor ALL, unlike in acute myelogenous leukaemia, it may be possible to distinguish residual normal progenitor/stem cells from the leukaemic cell clone.     

Factors affecting survival in allogeneic bone marrow transplantation

From 1979 to 1988, 82 allogeneic and 2 syngeneic bone marrow transplants (BMT) were performed in 78 patients (age range 13-49 years) with the following diagnoses: acute myelogenous leukemia (AML) (21 patients); acute lymphoblastic leukemia (ALL) (15 patients); chronic myelocytic leukemia in chronic, accelerated, or blastic phase (CML-CP, AP or BC) (25 patients); myelodysplastic syndrome (MDS) (1 patient); multiple myeloma (MM) (1 patient); Hodgkin's disease (HD) (1 patient); diffuse poorly differentiated lymphoma (DPDL) (1 patient); aplastic anemia (AA) (13 patients). Univariant analyses were carried out to determine factors of importance in predicting outcome. AML patients receiving transplants in remission had 12/19 (63%) survivors. Only one of seven ALL patients receiving transplants in remission survives free of disease, and none of eight patients receiving transplants in relapse survived. Six ALL patients relapsed. In CML, 6 of 16 (40%) patients receiving transplants in CP survive; two of nine patients (22%) in AP or BC survive. Of the 13 aplastic anemias, 8 (62%) survive. Graft-vs.-host disease (GVHD) was evaluated in 75 patients, 24 of 33 (73%) who developed GVHD died, compared to 24 of 44 (55%) who did not develop GVHD. Of the 30 patients given the combination of methotrexate (MTX) plus cyclosporine (CSP), only 23% developed GVHD, compared to 58% of those not given the combination. Interstitial pneumonia (IP) occurred in 16 patients and was fatal in 15. The introduction of daily acyclovir and weekly intravenous gamma globulin in 1985 was associated with little reduction in the frequency of IP (from 20% to 18%). However, survival increased from 21% to 47%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Isolated extramedullary relapse of acute lymphoblastic leukaemia after allogeneic bone marrow transplantation

Isolated extramedullary relapse of acute lymphoblastic leukaemia (ALL) with sparing of the marrow after allogeneic bone marrow transplantation (BMT) is a rare occurrence, and the mechanisms underlying the selective involvement of extramedullary sites remain undefined. These might be due to relapse in sanctuary sites where the leukaemic cells are resistant to chemotherapy, or a stronger putative graft-versus-leukaemia (GVL) effect in the marrow as compared with peripheral tissues. We report two ALL patients with repeated episodes of extramedullary relapse after BMT in whom both mechanisms might be operating. In the first patient, the marrow was in morphologic and molecular remission before isolated leukaemic relapse in the central nervous system (CNS) occurred. Subsequent secondary infiltration of leukaemic cells into the marrow was only evident molecularly but not morphologically, implying that the relapse had arisen in a sanctuary CNS site. In the second patient, a first relapse in the marrow, which was induced into morphologic and molecular remission by chemotherapy and donor lymphocyte infusion, was followed by extramedullary relapses without any subsequent involvement of the marrow. This suggested that factors, likely to be due to a GVL effect, were stronger in the marrow than in peripheral tissues.     

PCR-positivity in harvested bone marrow predicts relapse after transplantation with autologous purged bone marrow in children in second remission of precursor B-cell acute leukaemia

Purging of autologous bone marrow (BM) grafts of children in second remission after a relapse of precursor B acute lymphoblastic leukaemia (ALL) in the BM has been carried out in our laboratory since 1987, initially by complement mediated cell lysis. This protocol was extended by performing an immunorosette depletion before lysis with complement. The aim of the present study was to assess by polymerase chain reaction the presence of residual leukaemic cells in the BM grafts before and after purging. The results were then correlated to clinical outcome. In 24/28 patients a PCR product was obtained by amplification of IgH and/or TcR junctional regions. BM before purging was available for analysis in 13 patients. We found that leukaemic cells could be detected in 8/13 (62%) of these grafts before purging . All these eight patients experienced a relapse, regardless of whether the purging procedure had been successful (defined as achievement of PCR-negativity) or not. In contrast, none of the five patients with PCR-negative grafts before purging relapsed ( P  = 0.0008). One patient died due to transplant-related toxicity. Of the remaining 23 patients, nine patients received a PCR-positive BM graft after purging. All these nine patients experienced a relapse as compared to 6/14 whose BM was PCR-negative after purging ( P  = 0.0072). Two of eight PCR-positive BM grafts could be purged to PCR-negativity. Thus, improvements both in treatment of leukaemia and in purging efficacy are still needed.     

Antiproliferative activity of quercetin on normal bone marrow and leukaemic progenitors

We used an in vitro clonogenic assay in semi-solid medium to test the sensitivity of normal bone marrow and acute myeloid and lymphoid leukaemia progenitors to the flavonol quercetin. We have studied 14 acute myeloid (AML) and four acute lymphoid (ALL) leukaemias. All ALL and the vast majority of AML (12/14) had a high sensitivity to quercetin with more than 50% growth inhibition at 2 x 10(-6) M quercetin. One M3-AML was partially quercetin-sensitive displaying 60% surviving AML-colony forming units (CFU-AML) at a quercetin concentration of 10(-5) M. One M1-AML was resistant to the growth inhibitory effect of quercetin at a concentration of 2 x 10(-5) M. The clonogenic efficiency of both AML and ALL positively correlated with leukaemic colony-forming unit (CFU-L) sensitivity to quercetin suggesting that this parameter can be useful in predicting quercetin responsiveness of leukaemic cells. We have also studied the effect of various quercetin concentrations on colony formation by normal bone marrow cells. At a quercetin concentration of 10(-5) M, we observed (in five different experiments) a mean recovery of 53% and 65% of erythroid blast-forming units (BFU-E) and granulocyte-macrophage colony-forming units (CFU-GM), respectively. Thus, normal bone marrow appeared partially resistant to quercetin, being inhibited less than 50% by quercetin concentration higher than 2 x 10(-5). When normal bone marrow were deprived in CD34+ haematopoietic progenitors the resultant population became highly sensitive to quercetin, with a mean recovery of BFU-E and CFU-GM of 5% and 12% of controls respectively in the presence of 2 x 10(-5) M quercetin. Furthermore, CD34 progenitors, positively selected, appeared fully resistant to quercetin concentrations as high as 2 x 10(-5) M. Thus, CD34+ progenitors are a quercetin-resistant component in normal bone marrow. In conclusion, our results further provide a biological basis for the therapeutic use of quercetin, considering that this compound could inhibit leukaemic cell growth without suppressing normal haematopoiesis.     

Leukaemia-associated immunophenotypes (LAIP) are observed in 90% of adult and childhood acute lymphoblastic leukaemia: detection in remission marrow predicts outcome

Analysis of differentiation antigens on leukaemic blasts is routinely done for diagnostic purposes, i.e. determination of stage of differentiation and lineage assignment. Acute lymphoblastic leukaemias are also frequently characterized by a leukaemia-associated immunophenotype (LAIP), either the coexpression of differentiation antigens physiologically restricted to other stages of differentiation (asynchronous LAIP) or cell lineages (aberrant LAIP). We defined LAIP in 241 consecutive unselected B-lineage (n = 193) and T-lineage (n = 48) ALL by three-colour flow cytometry using directly conjugated monoclonal antibodies. The incidence of LAIP was found to be 91.7%. In 63% of patients two to six leukaemia-associated expression patterns were detected. In order to study the specificity of LAIP in a therapy-relevant setting, remission bone marrow samples from patients with B-lineage ALL were analysed for the expression of T-lineage-associated phenotypes on the normal bone marrow cells and vice versa. The frequency of all T-lineage LAIP+ cells and all aberrant B-lineage LAIP+ cells was <1% in regenerating bone marrow samples at different timepoints. The incidence and clinical significance of LAIP+ cells was studied in 196 remission marrows of 70 ALL patients (55 remaining in CCR, 14 with bone marrow relapse, one with isolated CNS relapse). The presence of >1% LAIP+ at two consecutive timepoints predicted 5/8 bone marrow relapses in B-lineage ALL. The occurrence of LAIP+ cells >1% in T-lineage ALL after induction therapy predicted relapse in 7/7 cases. In conclusion, flow cytometric detection of LAIP+ cells appears to be a powerful tool for the prediction of outcome in ALL.     

DNA and RNA determination in 111 cases of childhood acute lymphoblastic leukaemia (ALL) by flow cytometry: correlation of FAB classification with DNA stemline and proliferation

Flow cytometry with acridine orange was used in 111 cases of childhood acute lymphoblastic leukaemia (ALL) to determine simultaneously DNA index, cell cycle distribution and cellular RNA content in bone marrow samples. The overall incidence of DNA aneuploidy in the population was 40%. Significantly higher incidence of DNA aneuploidy was present in the L2 (70.6%) as compared to the L1 (34.1%) group (P = 0.007), using the FAB classification. No difference in the frequency of normal and abnormal DNA stemlines was found between newly diagnosed and relapsed patients. The L2 group had significantly higher proliferation (S phase = 12.4%) than L1 (S phase = 5.8%) (P = 0.01), but RNA content was not significantly different. The aneuploid group had significantly more (P = 0.01) cases with L2 morphology (28.6%) compared to the diploid group (8%) and proliferation was higher in DNA aneuploid (S-phase = 9.5%) compared to DNA diploid (S-phase = 4.7%) leukaemias. Likewise, RNA content was significantly higher in aneuploid than in diploid ALL (P = 0.006). These correlations between morphology, cell kinetics and DNA index elucidate biological properties of leukaemic cells with potentially prognostic value.     

Autologous bone marrow transplantation for acute leukaemia in remission

Between 1980 and 1985, 175 patients with acute leukaemia in first or subsequent complete remission (CR) were treated by chemotherapy or chemoradiotherapy followed by transfusion of autologous bone marrow cells that had been collected days or months previously. In 85 cases, autologous marrow cells were treated ex vivo with cytotoxic drugs or monoclonal antibodies with the intention of removing residual leukaemic cells. The actuarial relapse-free rate was 52% at 2 years. Of 89 patients autografted for acute non-lymphocytic (myeloid) leukaemia (ANLL), 60 were treated in first remission and 18 in second CR; their relapse-free rates at 2 years were 67% and 41% respectively (P less than 0.001). In contrast, of 77 patients autografted for acute lymphoblastic leukaemia (ALL), 32 were treated in first CR and 28 in second CR and their actuarial relapse free rates at 2 years were 56% and 55% respectively (P = NS). There was no significant difference in leukaemia relapse rates between patients autografted with purged and those autografted with non-purged marrow cells. These preliminary results suggest that autologous bone marrow transplantation may be valuable if offered to patients with ANLL in first CR or to patients with ALL in first or second CR but the need for marrow purging remains uncertain.     

Unrelated donor bone marrow transplantation for children with relapsed acute lymphoblastic leukaemia in second complete remission

Allogeneic sibling bone marrow transplantation (BMT) is the recommended treatment for relapsed childhood acute lymphoblastic leukaemia (ALL), but appropriate donors are only available in 30% of cases. Unfortunately, BMT from unrelated donors (UD) has been associated with high rates of severe graft-versus-host disease (GvHD) and transplant-related mortality (TRM). In an attempt to improve outcome in UD-BMT we have assessed the impact of T-cell depletion using CAMPATH-1 (anti-CD52) monoclonal antibodies in 50 consecutively referred patients with relapsed ALL in second remission. All were previously treated according to MRC protocols UKALL X and XI, and then given chemotherapy on MRC R1 from relapse until UD-BMT. 19 patients had relapsed on and 31 off therapy.
Patients and donors were fully matched at HLA-A, -B, -DR and -DQ loci in 29 cases and mismatched in 21 (four mismatched for more than one antigen). Pre-transplant conditioning comprised CAMPATH-1G, cyclophosphamide and total body irradiation. Bone marrow was T-cell depleted in vitro using CAMPATH-1 antibodies. Additional GvHD prophylaxis consisted of cyclosporin A (42 cases), cyclosporin plus methotrexate (four) or none (four). 47 patients engrafted. The incidence of acute GvHD was very low: two patients with grade II disease in the matched group, four with grade II–IV in the mismatched group. Only four patients have chronic GvHD. The actuarial event-free survival (EFS) at 2 years is 53%, with no significant difference between the matched and mismatched group. Further leukaemic relapse was the most important cause of failure.
These results are similar to the most favourable published reports for HLA-matched sibling BMT in relapsed ALL.     

Molecular analysis of the leukaemic B cell in adult and childhood acute lymphoblastic leukaemia

Immunoglobulin heavy chain gene (IgH gene) rearrangements are found in the majority of cases of B-lineage acute lymphoblastic leukaemia (ALL). We have examined bone marrow samples taken at presentation or relapse from 109 patients (79 adults and 30 children) and have performed sequence analysis of the complementarity determining region 3 (CDR3) on 65 alleles from 54 patients. We aimed to define immunoglobulin heavy chain (IgH) variable segment family use and investigate biological and structural features of the B cell in adult and childhood ALL. Using the FR1 fingerprinting method, a rearranged band was identified in 70 (89%) of 79 adult ALL and in 29 (97%) of 30 childhood ALL. This study found no preferential use or selection of IgH VH genes and no statistically significant structural differences between normal and leukaemic B cells in either adult and childhood ALL. An equal proportion of amplifiable cases of adult and childhood ALL uses more than one VH family gene (24/70, 34%, and 8/29, 27.5%, respectively). There were no significant differences in the structure or size of the CDR3 region and the variable (V) or joining (J) segment use in ALL patients compared to normal B cells. We observed that the N2 region was shorter than N1 in children whereas the opposite was observed in adults (not statistically significant). The J4 segment was a more common rearrangement in children than in adults, and in both groups J4 was more frequently associated with multiple D segment VDJ rearrangements. An increase in VH6 use in leukaemic alleles compared to normal B lymphocytes (2%) was observed but it was not statistically significant in our group of patients. Amongst children and adults, in-frame CDR3 junctions occurred in 78% and 64% of rearranged alleles, respectively, compared to 75% of in-frame sequences reported by others to occur among normal B cells.     

Myelopoietic Stem Cells (CFUc) in the Blood and Bone Marrow of Children with Acute Lymphoblastic Leukaemia and Lymphosarcoma,Cultivated without an Exogenous Supply of Colony Stimulating Factor (CSF)

26 children with acute lymphoblastic leukaemia (ALL) and 7 additional patients with lymphosarcoma in leukaemic transformation (LSA) have been studied with respect to the content of myelopoietic stem cell (CFUc) in blood and bone marrow. The methylcellulose culture technique (Iscove et al 1974) was employed in the absence of an exogenous source of colony stimulating factor (CSF). During active disease, CFUc colony formation was absent from patients with ALL, but was present in 2 patients with LSA. 2 therapeutic regimens were employed. Colony formation from bone marrow CFUc was highly variable during remission maintained by either regimen, with no clear relation to clinical stage, number of monocytes or circulating neutrophils. Patients with LSA consistently had high numbers of bone marrow CFUc. CFUc were low or absent from the blood. In conclusion, CFUc are absent from the bone marrow in active ALL, but may be present in active LSA. For the purpose of monitoring children with ALL during therapy, determination of blood or bone marrow CFUc was not found in this study to be helpful.     

Factors affecting the outcome of allogeneic bone marrow transplantation for adult patients with refractory or relapsed acute leukaemia

We evaluated the outcome of allogeneic bone marrow transplantation (BMT) for advanced acute myeloid leukaemia (AML) and acute lymphoblastic leukaemia (ALL) in 383 adult patients in nine Australian adult BMT centres between 1981 and 1997. The median overall survival for the group was 4.8 months, with an estimated 5-year survival of 18%. 28% of patients died of transplant-related toxicities within the first 100 d. Progressive disease was responsible for 48% of deaths. Multi-factor analysis demonstrated that AML (v ALL), disease status (second complete remission [CR2] v others), age (< 40 years) and duration of prior first complete remission (CR1) (> 6 months) were pre-transplant variables significantly associated with improved survival. Acute graft-versus-host disease (GVHD) of any grade reduced the rate of relapse in both AML and ALL, but only grades I-II were associated with improved survival. Both limited and extensive chronic GVHD were associated with increased survival. Only patients with AML in untreated first relapse or CR2, with a duration of CR1 > 6 months, or patients with T ALL, had a 5-year survival > 20%. Transplants for AML in induction failure or pre-B ALL in untreated first relapse or CR2 had an intermediate outcome, with 5-year survival of 10-20%. A 5-year survival of < 10% was observed for patients transplanted for ALL in induction failure or for pre-B ALL or AML in refractory first relapse or beyond CR2. These results suggest that for most adult patients with advanced acute leukaemia an allograft offers only a small chance of cure.     

Predictive value of bone marrow cultures in 48 patients with acute myeloblasts leukaemia or myelodysplasia both secondary to treatment of other malignant diseases

The growth pattern of bone marrow cells in agar cultures was studied in 48 patients with acute myeloblasts leukaemia or myelodysplasia, secondary to cytoreductive treatment, and compared to other laboratory findings. At diagnosis the status of the patients was: acute myeloblastic leukaemia (AML) in 9, acute myeloproliferative syndrome (AMS) in 13 and preleukaemic syndrome (PL) in 26 patients. 20 of the 39 patients with AMS and PL developed acute leukaemia, 15 of them within 1 year. 15 died of complications to cytopenia and only 4 are still alive and without leukaemia, observed from 8 to 55 months. Progression to AML was predicted from the agar cultures by increased cluster growth. Among 18 patients with increased cluster growth at diagnosis 14 subsequently developed AML. Among 21 patients with normal or decreased cluster growth at diagnosis 6 patients developed AML, but after conversion of the growth pattern to increased cluster growth. In 2 patients the increased cluster growth disappeared spontaneously and the patients are long-term leukaemia-free survivors. Colony growth pattern, conversely, was not related to leukaemic progression. Only 1 patient had normal growth pattern at diagnosis with respect to both clusters and colonies. Survival was short, with a median of about 7 months, unrelated to growth pattern and leukaemic progression.     

Predictive value of bone marrow cultures in 48 patients with acute myeloblastic leukaemia or myelodysplasia both secondary to treatment of other malignant diseases

The growth pattern of bone marrow cells in agar cultures was studied in 48 patients with acute myeloblastic leukaemia or myelodysplasia, secondary to cytoreductive treatment, and compared to other laboratory findings. At diagnosis the status of the patients was: acute myeloblastic leukaemia (AML) in 9, acute myeloproliferative syndrome (AMS) in 13 and preleukaemic syndrome (PL) in 26 patients. 20 of the 39 patients with AMS and PL developed acute leukaemia, 15 of them within 1 year. 15 died of complications to cytopenia and only 4 are still alive and without leukaemia, observed from 8 to 55 months. Progression to AML was predicted from the agar cultures by increased cluster growth. Among 18 patients with increased cluster growth at diagnosis 14 subsequently developed AML. Among 21 patients with normal or decreased cluster growth at diagnosis 6 patients developed AML, but after conversion of the growth pattern to increased cluster growth. In 2 patients the increased cluster growth disappeared spontaneously and the patients are long-term leukaemia-free survivors. Colony growth pattern, conversely, was not related to leukaemic progression. Only 1 patient had normal growth pattern at diagnosis with respect to both clusters and colonies. Survival was short, with a median of about 7 months, unrelated to growth pattern and leukaemic progression.     

The metabolic bone disease of primary sclerosing cholangitis

The incidence and severity of osteopenic bone disease in primary sclerosing cholangitis is poorly defined. Clinical, biochemical and radiographic assessment and bone mineral density measurements of the lumbar spine were carried out in two groups of patients. Group 1 consisted of 30 patients with advanced primary sclerosing cholangitis; group 2 consisted of 18 patients with newly diagnosed primary sclerosing cholangitis. Only one patient had bone pain. All patients were normocalcemic; two had elevated serum parathormone levels. Fourteen patients (47%) from group 1 but no patients from group 2 had low serum 25-hydroxyvitamin D levels. Mean bone mineral density was significantly reduced in group 1 patients (0.97 +/- 0.04 gm/cm2) compared with age-matched and sex-matched controls (1.25 +/- 0.01 gm/cm2, p less than 0.0001), and in 15 patients (50%) bone mineral density was below the fracture threshold (0.98 gm/cm2). The bone mineral density in group 2 was not significantly different from controls, and no patient was below the fracture threshold. In neither group did bone mineral density correlate with serum bilirubin, 25-hydroxyvitamin D, fecal fat excretion, previous drug therapy or the presence of chronic ulcerative colitis. Histomorphometrical examination of bone from four group 1 patients showed increased bone resorption, reduced bone formation, moderate-to-severe osteopenia and no osteomalacia. In conclusion, severe osteopenic bone disease is common in advanced primary sclerosing cholangitis and, like that seen in other cholestatis diseases, is consistent with osteoporosis.     

Loss of the Y chromosome in bone marrow cells: results on 1907 consecutive cases of leukaemia and preleukaemia

Loss of the Y chromosome with a resulting 45, X0 karyotype is observed in normal bone marrow cells of elderly males but also in haematological malignancies. Whether Y loss in neoplastic cells is related to the process seen in normal ageing or is part of the carcinogenic process is unknown. The present study concerns the cytogenetic data from 1907 consecutive leukaemic or preleukaemic male patients with special regard to the presence or absence of the Y chromosome. Sixty-five patients (3.4%) had a 45, X-Y clone in their bone marrow (BM) cells. Loss of Y was rare below the age of 50 but increased in older patients, reaching 25% of the men over 80. Sixteen patients (0.08%) had more than 90% X0 cells in their BM. A correlation between Y loss and leukaemia could be established in seven cases, three of which were acute myeloid leukaemia M2 subtype where -Y is known to be a secondary event. In three other cases, -Y was part of a complex karyotype. Only one patient exhibited a 45, X0 karyotype, with no other rearrangement, that could be positively correlated with the neoplastic process.     

Chromosomal studies after bone marrow transplantation for leukaemia in children

Chromosomal studies were performed on 114 blood samples and 117 bone marrow samples, taken systematically over a period of 4 months after bone marrow transplantation (BMT) in 42 children grafted for acute lymphoblastic leukaemia (ALL) (n = 20), acute myeloid leukaemia (AML) (n = 16), non-Hodgkin's lymphoma (NHL) (n = 2) and myelodysplastic syndrome (MDS) (n = 4). In some cases, follow-up investigations were performed. In the first 4 months following BMT, mixed chimerism was frequently observed in blood of AML (25%), ALL (30%), NHL (100%) cases and in bone marrow samples of ALL (35%). The presence and relative number of a patient's own metaphases found shortly after transplantation was not related to leukaemia relapse and probably represents residual non-malignant haematopoietic precursor cells of the host. In only one child grafted for MDS with 45,XY, -7 karyotype was the marker clone still detectable in bone marrow at day +437 post-BMT. This patient shows no recurrence of the MDS and has a sustained haematological recovery at the time of writing, i.e. 4.5 years post-BMT. In 11 other patients, various structural chromosomal abnormalities (not related to the original leukaemia) were found in both peripheral blood and bone marrow. In three different patients structural anomalies were also found in bone marrow and blood samples from donor-derived cells. This indicates that, besides irradiation, there are other as yet unidentified factors (e.g. drugs), which are capable of inducing chromosomal anomalies in the post-BMT period.