Expression of mdr1 and mrp in the normal B-cell homologue of B-cell chronic lymphocytic leukaemia

B-cell chronic lymphocytic leukaemia (CLL) cells commonly express the multidrug resistance phenotype. The aim of this study was to establish whether the normal homologue in B-cell ontogeny of B-CLL also expressed the multidrug resistance (mdr) phenotype. Human tonsillar lymphocytes were sorted to yield two B-cell subsets based on the expression of CD19, CD5 and CD10. The normal homologue was represented by a population of B cells that was CD19 positive, CD10 negative and weakly expressed CD5. Based upon functional analysis and the detection of mdr1 mRNA by semi-quantitative PCR, these cells expressed the mdr phenotype. In contrast, functional multidrug resistance could not be demonstrated in CD19-positive CD10-positive cells with strong expression of CD5, nor could mdr1 mRNA be found in these cells. MRP was variably expressed in both B-cell subsets with no discernable differences in the pattern of expression. We conclude that normal B cells with a phenotype resembling that of B-CLL cells express the multidrug resistance phenotype.     

Transient leukaemia cutis in chronic lymphocytic leukaemia

The sequelae of secretory otitis media (SOM) were monitored in 72 adult patients with SOM who were followed up for an average of 33 months. It was found that SOM became chronic and retraction of the tympanic membrane appeared as a function of the pneumatization of the mastoid. Ears with poor pneumatization (less than 6 cm2) developed chronic SOM in 52.2% of cases, as compared with 20% in cases with well-pneumatized ears (6 cm2 and above). Atelectasis developed in 37.3% of poorly pneumatized ears, and in only 5.7% of well-pneumatized ears. These sequelae may therefore be linked pathogenetically to the extent of pneumatization, as both the SOM and the sequelae appeared many years after formation and maturation of the pneumatic system. This study supports other studies that view the mastoid pneumatic system as an organ, as a middle ear pressure buffer. Well-pneumatized ears rarely develop a negative pressure and are seldom associated with chronic sequelae. Ears with poorly pneumatized mastoids lack the physiological function of such a pressure buffer. Ears with a tendency to develop a negative gas balance, whether as a result of deficient ventilation or excessive diffusion, will therefore develop a negative pressure more readily when their pneumatic system is underdeveloped, and consequently will be more prone to develop chronic sequelae.     

Serum erythropoietin in chronic lymphocytic leukaemia

OBJECTIVE: To establish whether there is any improvement in pregnancy and implantation rates after administration of "low-dose," long-acting glucocorticoids during transfer of cryopreserved-thawed embryos. SETTING: An IVF unit in a university hospital. DESIGN: Prospective, randomized study. Ninety-nine consecutive transfer cycles of frozen-thawed embryos to the uterine cavity of randomly chosen women diagnosed as having tubal factor infertility only. Fifty-two patients underwent transfer of frozen-thawed embryos and received 0.5 mg of dexamethasone; 47 women (control group) did not receive the drug during transfer. PATIENTS: Normal ovulatory patients with tubal factor infertility. INTERVENTIONS: Oral dexamethasone administration before, during and after transfer of thawed embryos. MAIN OUTCOME MEASURES: Pregnancy and implantation rates. RESULTS: The pregnancy rate was 13.5% (7/52) in patients treated with the "low-dose" regimen of dexamethasone compared with 12.8% (6/47) in the control group. The implantation rate was similar. CONCLUSION: Our results demonstrated that the use of 0.5 mg dexamethasone for an immuno-suppressive effect, administered for a short period to patients diagnosed as having "pure" tubal factor infertility, did not improve the implantation or pregnancy rates.     

Anticipation in familial chronic lymphocytic leukaemia

A recent analysis of literature reports of familial clusters of chronic lymphocytic leukaemia (CLL) suggested that affected offspring are diagnosed at an age 21 years less than CLL parents. Such an analysis risks sampling bias. We avoided these potential sources of bias by systematic ascertainment of CLL families. Statistical analysis of 10 such families showed a significant decline of 22 years between the mean ages at diagnosis of disease in parents and offspring. This confirms the analysis of literature reports and provides the first systematic investigation of a phenomenon which, if familial clustering of CLL cases is considered due to genetic effects, points to familial CLL manifesting anticipation.     

Myelomonocytic antigens in B-cell chronic lymphocytic leukemia

The clinical significance of myelomonocytic (MyMo) antigens in B-cell chronic lymphocytic leukemia (B-CLL) is unclear. We have analyzed the expression of MyMo antigens (CD13, CD14 (LeuM3, My4, Mo2), CD15, CD11b, CD11c, CD33 and CD68) on B-lymphocytes (CD19+) in 105 B-CLL patients and in 35 controls. A double direct staining technique and flow cytometric analysis was performed. The expression of MyMo antigens on the control group did not exceed 4% B-lymphocytes. A MyMo antigen was considered as positive when present in > or = 10% of B-lymphocytes. Among the B-CLL patients, 28 (26.7%) were positive for CD11c, 21 (20.0%) for CD11b, nine (8.6%) for CD15, five (4.8%) for CD13, two (1.9%) for Mo2, and one (1.0%) for My4. No patient was positive for LeuM3, CD33 or CD68. CD11c was more frequently expressed in patients with a short lymphocyte doubling time (< 12 months) (P = 0.05) and CD11b in the group with a higher number of lymphoid areas involved (P = 0.02). No correlation was found between lymphoid morphology and MyMo antigen expression. Fourteen of the 80 patients at risk subsequently progressed to a more advanced stage. Multivariate analysis identified hemoglobin (P = 0.004) and CD11b positivity (P = 0.009) as independent variables for disease progression. Fifteen patients died during evolution. Seven out of the 21 CD11b positive patients and eight of the 84 CD11b negative patients died (LR: P = 0.02, BG: P = 0.05). In the multivariate analysis, only CD11b positivity (> or = 10%) added prognostic value to clinical stages.     

Common expression of the multidrug resistance marker P-glycoprotein in B-cell chronic lymphocytic leukaemia and correlation with in vitro drug resistance

The expression of P-glycoprotein (Pgp), which is associated with multidrug resistance (MDR), was investigated in 20 B-cell chronic lymphocytic leukaemia (B-CLL) patients by flow cytometry using two Pgp-specific monoclonal antibodies (mAb), MRK-16 which recognizes an extracellular epitope, and JSB-1 which recognizes an intracellular epitope. Sixteen (80%) patients were positive with MRK-16 whereas all patients were positive with JSB-1. The proportion of Pgp-positive lymphocytes from each patient sample varied from 2-94% for MRK-16 and 20-93% for JSB-1. There was no correlation between the level of positivity and disease stage or treatment history. In vitro drug resistance to vincristine (VCR) and doxorubicin (DOX) was determined by the colorimetric MTT assay. All patients were resistant to one or both drugs being consistent with the expression of Pgp. There was no correlation between the level of resistance and disease stage or drug treatment. We investigated the expression of Pgp in the normal counterpart of the B-CLL cells, CD5+CD19+ B-lymphocytes. A minor subpopulation (3%) of CD5+CD19+ lymphocytes isolated from normal controls expressed Pgp suggesting that these cells may be the potential precursors to the B-CLL cell. We conclude that Pgp expression and drug resistance are inherent characteristics of the B-CLL lymphocyte.     

Aspirin and salicylate induce apoptosis and activation of caspases in B-cell chronic lymphocytic leukemia cells

We analyzed the effect of aspirin, salicylate, and other nonsteroidal antiinflammatory drugs (NSAIDs) on the viability of B-chronic lymphocytic leukemia (B-CLL) cells. Aspirin induced a decrease in cell viability in a dose- and time-dependent manner. The mean IC50 for cells from 5 patients was 5.9 +/- 1.13 mmol/L (range, 4.4 to 7.3 mmol/L). In some cases, 2.5 mmol/L aspirin produced an important cytotoxic effect after 4 days of incubation. No effect was observed with other NSAIDs, at concentrations that inhibit cyclooxygenase, such as ketorolac (10 micromol/mL), NS-398 (100 micromol/mL), or indomethacin (20 micromol/mL), thus suggesting the involvement of cyclooxygenase-independent mechanisms in aspirin-induced cytotoxicity. Salicylate also produced dose-dependent cytotoxic effects on B-CLL cells and the mean IC50 for cells from 5 patients was 6.96 +/- 1.13 mmol/L (range, 5 to 7.8 mmol/L). Both aspirin and salicylate induced DNA fragmentation and the proteolytic cleavage of poly(ADP(adenosine 5'-diphosphate)-ribose) polymerase (PARP), demonstrating that both compounds induce apoptosis of B-CLL cells. Finally, inhibition of caspases by Z-VAD.fmk blocked proteolytic cleavage of PARP, DNA fragmentation, and cytotoxicity induced by aspirin. Mononuclear cells from normal donors showed a lower sensitivity than cells from B-CLL patients to aspirin as determined by analysis of cell viability. B and T lymphocytes from normal donors and T lymphocytes from CLL patients are more resistant to aspirin-induced apoptosis, as determined by analysis of phosphatidylserine exposure. These results indicate that aspirin and salicylate induce apoptosis of B-CLL cells by activation of caspases and that this activation involves cyclooxygenase-independent mechanisms.     

2-Chlorodeoxyadenosine therapy in advanced chronic lymphocytic leukaemia

The therapeutic potential of 2-chlorodeoxyadenosine (CdA) in patients with advanced chronic lymphocytic leukaemia (CLL) remains controversial with response rates in clinical trials ranging from 44 to 67%. This report describes our experience with CdA in 22 CLL patients having already undergone previous treatment. CdA was given by continuous intravenous infusion at a dose of 4 mg/m2/day for 7 days (4 patients) or as 2-h intravenous infusions at a dose of 5.6 mg/m2/day for 5 days (18 patients). Partial (n = 5) or complete (n = 2) response was obtained in 7 cases. As compared to unresponsive patients, responding subjects received CdA earlier in the course of their disease (mean interval between diagnosis and CdA therapy 58 vs 102 months), were less thrombocytopenic at initiation of CdA (mean platelet count 165 x 10(9)/L vs 81 x 10(9)/L) and experienced less severe neutropenia during the first course of therapy (mean minimal neutrophil count 1.55 x 10(9)/L vs 0.43 x 10(9)/L). None of 6 patients with CLL refractory to fludarabine responded to CdA. An evaluation of haematological toxicity during the first course of treatment showed grade 4 neutropenia (< 0.5 x 10(9)/L) in 7 cases and grade 4 thrombocytopenia (< 25 x 10(9)/L) in one of 19 cases where the platelet count was greater than 25 x 10(9)/L at initiation of CdA. In comparison with earlier reports, the present series of patients had received relatively heavy prior therapy, experienced more severe haematological toxicity and demonstrated a lower total response rate.     

The effect of 2-h infusion of 2-chlorodeoxyadenosine (cladribine) with prednisone in previously untreated B-cell chronic lymphocytic leukaemia

2-Chlorodeoxyadenosine (2-CdA) is a new antimetabolite chemotherapeutic agent active in indolent lymphoid malignancies. In this retrospective study, 69 previously untreated patients with B-cell chronic lymphocytic leukaemia (B-CLL) were treated with 2-CdA administered at a dose of 0.12 mg/kg daily in 2-h intravenous infusion for 5 consecutive days. 45 patients also received prednisone 30 mg/m2 orally each day for 5 days starting with 2-CdA courses. Patients were given 2-6 courses (mean 4.6) of 2-CdA repeated usually at monthly intervals. If a complete response was achieved, no further 2-CdA courses were administered. Guidelines for response were those developed by the NCI Sponsored Working Group. Complete response (CR) was achieved in 26 (38%) and partial response (PR) in 27 (39%) cases, giving an overall response rate of 77%. 16 patients (23%) did not respond to 2-CdA. In the subgroup of 45 patients receiving 2-CdA with prednisone, CR was obtained in 15 (33%) and PR in 20 (44%) patients giving an overall response rate of 78%. CR was achieved in 11 (46%) out of 24 patients treated only with 2-CdA and in 7 cases (29%) PR was observed, giving an objective response rate of 75%. The differences between both subgroups were not statistically significant. However, we observed a relationship between the response and the number of courses of 2-CdA given in patients receiving and those not receiving prednisone. In the subgroup receiving 2-CdA with prednisone, an earlier response to 2-CdA was observed. In this group a response was achieved in 9 (20%) patients after two courses of 2-CdA and in 18 (40%) after four courses. In the subgroup receiving only 2-CdA, 17 (71%) responses were obtained after six cycles.     

IgG subclass levels in patients with B cell chronic lymphocytic leukaemia

Patients with B-cell chronic lymphocytic leukaemia (BCLL) have low levels of serum IgG. In order to determine if this is a pan IgG deficiency or a selective suppression of one or more IgG subclasses, levels of IgG 1, 2, 3 and 4 in nine BCLL patients were determined and compared to those of nine age and sex matched controls. No significant differences were found in the levels of IgG1 and IgG2, but the patients were found to have significantly lower levels of IgG3 (p < 0.05) and IgG4 (p < 0.05). Selective deficiencies of these isotypes may explain the particular pattern of infection seen in BCLL patients.     

Heterogenous response of B lymphocytes to transforming growth factor-beta in B-cell chronic lymphocytic leukaemia: correlation with the expression of TGF-beta receptors

We investigated the potential role of transforming growth factor-beta (TGF-beta) on spontaneous and cytokine-induced proliferation of B-cell chronic lymphocytic leukaemia (B-CLL) cells in vitro. Purified B lymphocytes from 21 B-CLL patients were cultured for 5 d in the presence of medium alone, IL-2 and/or IL-10, in the presence or absence of TGF-beta, and proliferation was measured by 3H-thymidine incorporation. TGF-beta inhibited B-cell proliferation in the majority of patients (15/21) but no inhibition was detected in 6/21 patients whatever the type of stimulant used. Addition of neutralizing antibodies to TGF-beta increased spontaneous and cytokine-induced proliferation; this effect was dose dependent and specific because addition of an irrelevant chicken IgG had no effect on B-CLL proliferation. In resistant patients, neutralizing antibodies to TGF-beta did not increase the proliferation. The expression of TGF-beta receptors on B-CLL cells was significantly lower than the one observed on normal CD5+ B lymphocytes for which the sensitivity to TGF-beta inhibition was more marked than in CLL. In addition, we found a strong correlation between the response of leukaemic B cells to TGF-beta inhibitory action and the expression of TGF-beta receptors on these cells. In summary, TGF-beta appears to function in CLL as a negative regulator of B lymphocytes but loss of responsiveness to this factor accompanied by a decrease of TGF-beta receptor expression, might provide a selective advantage to B-CLL lymphocytes.     

The cellular biology of B-cell chronic lymphocytic leukemia

In conclusion, B-CLL cells through their immunophenotype have the functional potential required to interact with cells in what has been called the immunological synapse, i.e. the cognate interactions between T-cells, antigen-presenting cells and B-cells during immunopoiesis. The data reviewed herein provides substantial evidence to suggest that B-CLL cells in fact can interact, not only with T-cells but also with endothelial cells and stromal cells in the bone marrow. These interactions, in particular signaling through CD40, contribute to extended survival and proliferation of B-CLL cells and, thereby, the risk of complete malignant transformation of the clone. Therefore, this review would suggest that the answers to how B-CLL is initiated may be found in molecules responsible for the normal regulation of immunopoiesis. Transformation to malignancy, by contrast, is likely to be caused by loss of control over the G1 restriction in the cell cycle in B-CLL cells.     

Twenty years of research on B-cell chronic lymphocytic leukemia

The typical MRI features of the most common pancreatic diseases, such as pancreatitis and adenocarcinoma of the pancreas, have been established. However, even in these common pancreatic disorders, MRI correlation with the underlying pathology is limited for clinical reasons. We emphasize MR-pathological correlation of inflammatory and neoplastic pancreatic changes, including pancreatitis, adenocarcinoma, acinar cell carcinoma, rare cystic and solid pancreatic neoplasms, and islet cell tumors. By highlighting the correlation of key pathological features with MR findings, a better understanding of the MR appearance of pancreatic pathology can be provided. In addition, MRI may prove a powerful tool in detection and characterization of pancreatic tumors.     

Rb1 gene expression in B-cell lymphocytic leukaemia cases with deletion in the 13q14 region

Recent studies have been carried out to delineate further the role of the Rb1 gene in B-cell chronic lymphocytic leukaemia (B-CLL). The suggested role of the Rb1 gene in this disease was based on cytogenetic data. CLL patients (40 in toto) were examined using cytogenetic and molecular biological methods. R-banding analysis of metaphase chromosomes revealed aberrations in only seven cases containing either the Rb1 gene or a chromosome 13 monosomy. No evident differences were found by RT-PCR analysis of Rb1 gene expression. The amounts of the RT-PCR products obtained appeared to be approximately equal in all cases, and was independent of the clinical stage, immunophenotypes and LPS or TPA stimulation.     

Myelodysplasia occurring after fludarabine treatment for chronic lymphocytic leukaemia

The purine analogue, fludarabine, is of proven efficacy in the treatment of lymphoid malignancies. The drug appears to be well tolerated with minimal side-effects, and few toxicities have been observed. A case of myelodysplasia occurring after therapy with fludarabine is presented and its implications are discussed.     

Trisomy 12 in B-cell chronic lymphocytic leukaemia: an evaluation of 33 patients by direct fluorescence in situ hybridization (FISH)

An adaptation of the standard fluorescence in situ hybridization (FISH) technique allowing rapid analysis (4 h) has been used to study the prevalence of trisomy 12 in 33 patients with B-CLL, of whom 54% have been shown to have this abnormality. The presence of trisomy 12 has been compared with clinical parameters, and there may be a relationship between the prevalence of trisomy 12 in B-CLL and duration of disease.