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Lipoprotein lipase (LPL) is a prognostic marker in B-cell chronic lymphocytic leukemia (B-CLL) related to immunoglobulin V(H) gene (IgV(H))mutational status. We determined gene expression profiles using Affymetrix U133A GeneChips in two groups of B-CLLs selected for either high ('LPL+', n=10) or low ('LPL-', n=10) LPL mRNA expression. Selected genes were verified by real-time PCR in an extended patient cohort (n=42). A total of 111 genes discriminated LPL+ from LPL- B-CLLs. Of these, the top three genes associated with time to first treatment were Septin10, DMD and Gravin (P

The translocation t(8;16)(p11;p13) is associated with acute myeloid leukemia displaying monocytic differentiation (AML FAB M4/5) and fuses the MOZ (also named MYST3) gene (8p11) with the CBP (also named CREBBP) gene (16p13). Detection of the chimeric RNA fusions has proven difficult; only three studies have described successful amplification of the chimeric MOZ-CBP and CBP-MOZ fusions by reverse transcriptase-polymerase chain reaction (RT-PCR). We analyzed four cases of AML M4/5 with t(8;16)(p11;p13) by RT-PCR and fluorescence in situ hybridization (FISH) and characterized the reciprocal RNA fusions from three cases. We cloned both genomic translocation breakpoints from one case by long-range PCR and successfully applied RT-PCR to monitor minimal residual disease (MRD) between clinical complete remission and relapse. In three cases, the genomic breakpoints occurred in MOZ intron 16 and CBP intron 2. In one case, no fusion transcript was detected. The available data suggest clustering of t(8;16)(p11;p13) breakpoints in these introns leading to reciprocal in-frame MOZ exon 16/CBP exon 3 and in-frame CBP exon 2/MOZ exon 17 chimeric transcripts in the majority of cases. The described RT-PCR strategy may be valuable both for the routine detection of the t(8;16)(p11;p13) as well as for monitoring of MRD in this prognostically unfavorable patient group. [ABSTRACT FROM AUTHOR]

To compare the clinical relevance of drug resistance factors in de novo acute myeloid leukemia (AML), we determined their relationship to both response to induction chemotherapy and survival of the patients in univariate as well as multivariate analyses. The drug resistance factors immunocytochemically studied in 111 patients at the time of diagnosis included the lung resistance protein (LRP), P-glycoprotein (P-gp), multidrug resistance protein (MRP1) and bcl-2. In the univariate analyses, age (P = 0.005), karyotype (P = 0.03), LRP (P = 0.003), P-gp (P = 0.02) and bcl-2 (P = 0.03) predicted for response to induction chemotherapy, whereas MRP1 had no predictive value. Age (P = 0.05), karyotype (P = 0.05) and LRP (P = 0.03) retained their predictive value in the multivariate logistic regression analyses. With regard to overall survival, age (P = 0. 008), karyotype (P = 0.006), LRP (P = 0.001) and P-gp (P = 0.01) were of prognostic value in the univariate Cox regression analyses but only age (P = 0.01), karyotype (P = 0.02) and LRP (P = 0.01) retained their prognostic significance in the multivariate analyses. A risk score based on the number of independent prognostic factors allowed division of patients into four groups with different outcome. In these groups, the complete remission rates were 93%, 75%, 47% and 33%, respectively, and median overall survival was 2.4, 1.2, 0.6 and 0.2 years, respectively. Thus, several drug resistance factors did predict outcome in the univariate analyses but LRP was the only drug resistance factor with independent predictive and prognostic significance. The proposed risk score might be useful for risk-adapted treatment in the future. Leukemia (2000) 14, 68-76. [ABSTRACT FROM AUTHOR]

A letter to the editor on sequential gene expression profiling in chronic lymphocytic leukemia treatment for identifying predictive markers and novel therapeutic target is presented.

A letter to the editor on the expression of multiple myeloma oncogene as a prognostic marker in patient with multiple myelona is presented.

Presents a letter to the editor in response to the article "Remission of Pure Red Cell Aplasia in T-cell Receptor γδ-Large Granular Lymphocyte Leukemia After Therapy With Low-Dose Alemtuzumab," published in previous issue.

We investigated the pattern of lipoprotein lipase (LPL) expression in B-cell chronic lymphocytic leukemia (B-CLL) and assessed its prognostic relevance. Expression of LPL mRNA as well as protein was highly restricted to leukemic B cells. The intensity of intracellular immunoreactivity of LPL was higher in samples of patients with unmutated immunoglobulin heavy-chain variable region genes (IGVH) compared to those with mutated IGVH genes. LPL mRNA levels in peripheral blood mononuclear cells (PBMNC) from 104 CLL patients differed by 1.5 orders of magnitude between cases with mutated (N=51) or unmutated (N=53) IGVH (median: 1.33 vs 45.22 compared to normal PBMNC). LPL expression correlated strongly with IGVH mutational status (R=0.614; P<0.0001). High LPL expression predicted unmutated IGVH status with an odds ratio of 25.90 (P<0.0001) and discriminated between mutated and unmutated cases in 87 of 104 patients (84%). LPL expression was higher in patients with poor risk cytogenetics. High LPL expression was associated with a shorter treatment-free survival (median 40 vs 96 months, P=0.001) and a trend for a shorter median overall survival (105 months vs not reached). Our data establish LPL as a prognostic marker and suggest functional consequences of LPL overexpression in patients with B-CLL.Leukemia (2005) 19, 1216–1223. doi:10.1038/sj.leu.2403748 Published online 28 April 2005 [ABSTRACT FROM AUTHOR]

Molecular and genetic events associated with the transition from monoclonal gammopathy of undetermined significance (MGUS) to multiple myeloma (MM) are still poorly characterized. We investigated serial bone marrow specimens from 11 patients with MGUS who eventually progressed to MM (MM post-MGUS) by interphase fluorescence in situ hybridization for immunoglobulin heavy-chain gene (IgH) translocations and chromosome 13q deletions (del(13q)). In nine patients, IgH translocations were present both in MGUS and MM post-MGUS plasma cells, including three t(11;14)(q13;q32) and one t(4;14)(p16;q32), which was observed already 92 months prior to MM. Similarly, all five MM patients with del(13q) had this aberration already at the MGUS stage. Two patients without IgH translocation and del(13q) had chromosomal gains suggesting hyperdiploidy, but IgH translocations and/or del(13q) did not emerge at MM post-MGUS. IgH translocations and del(13q) are early genetic events in monoclonal gammopathies, suggesting that additional events are required for the transition from stable MGUS to progressive MM.Leukemia (2004) 18, 1879-1882. doi:10.1038/sj.leu.2403518 Published online 23 September 2004 [ABSTRACT FROM AUTHOR]

Activation-induced cytidine deaminase (AID) is essential for somatic hypermutation of B-cells. We investigated the expression of AID mRNA by real-time polymerase chain reaction (PCR) in peripheral blood mononuclear cells of 80 patients with B-CLL. AID expression was detected in 45 of 80 patients (56%) at various levels, but was undetectable in 35 patients (44%). AID PCR positivity was associated with unmutated IGVH gene status (22 of 25 patients; P=0.002) and unfavourable cytogenetics (18 of 23 patients with deletion in 11q or loss of p53; P=0.040). Using a threshold level of 0.01-fold expression compared to Ramos control cells, even more significant associations were observed (P=0.001 for IGVH; P=0.002 for cytogenetics). A correlation was observed between individual AID levels and the percentage of VH homology (R=0.41; P=0.001). AID positivity predicted unmutated IGVH status with an odds ratio of 8.31 (P= 0.003) and poor risk cytogenetics with an odds ratio of 3.46 (P= 0.032). Significance was retained after adjustment for Binet or Rai stages. AID mRNA levels were stable over time. These data suggest a potential role of AID as a prognostic marker in B-CLL. [ABSTRACT FROM AUTHOR]

Karyotype is an important prognostic factor in patients with newly diagnosed acute myeloblastic leukaemia (AML). The prognostic value of cytogenetics on the outcome of patients with AML in relapse has not yet been well defined. We analysed the clinical outcome of 152 patients with de novo, chemotherapy-treated AML in first relapse according to the cytogenetic classification of the United Kingdom Medical Research Council. The rate of second complete remission (CR) (88, 64 and 36%) and the probability of survival at 3 years (43, 18 and 0%) were significantly different between the favourable, intermediate and adverse cytogenetic risk groups, respectively. Compared to the favourable group, the relative risk (RR) of death (multivariate analyses) was 2.6 (confidence interval (CI): 1.5-4.4, P<0.001) for the intermediate and 3.7 (CI: 1.7-7.9, P=0.001) for the adverse group. The prognostic value of the duration of first CR was confirmed (RR of death: 2.0 (CI: 1.0-4.0) for each additional year in first CR), whereas the FLT3 mutation obtained at diagnosis did not markedly influence the outcome of patients with AML in relapse. In conclusion, our results indicate that both karyotype and the duration of first CR are independent prognostic factors for patients with de novo AML in first relapse.Leukemia (2004) 18, 293-302. doi:10.1038/sj.leu.2403243 Published online 11 December 2003 [ABSTRACT FROM AUTHOR]

C2B8 (Rituximab, MabThera) is a chimeric mouse/human monoclonal antibody (mAb) directed against the human B cell-restricted cell surface antigen CD20 which is used as an alternative medication in the treatment of B cell non-Hodgkin lymphomas (NHL). Treatment of CD20+ B cells with C2B8 triggers different cell damaging effects including complement-dependent lysis of tumor cells, antibody-dependent cellular cytotoxicity and induction of apoptosis. Dendritic cells (DC) have recently been shown to ingest cell debris and to present associated antigens even on MHC class I molecules, a mechanism called cross-presentation. In this study, we investigated whether C2B8 treatment of lymphoma promotes the induction of CD8+ T cell responses against lymphoma cell-associated antigens via, cross-presentation. We used Daudi lymphoma cells as a model system in our studies and could demonstrate, that C2B8-treated Daudi cells undergo apoptosis, are phagocytosed by DC and induce in DC typical features of maturation; among them, the induction of CD83 expression as well as the up-regulation of prominent accessory molecules (CD40, CD86) and MHC molecules. Importantly, upon co-culture of such lymphoma cell-pulsed DC with autologous T cells, we could induce efficient cytotoxic T cell (CTL) responses against Daudi cell-associated antigens. These findings suggest that antibody treatment of tumor cells can, in addition to its direct cell damaging effects, under certain conditions, contribute to an induction of potentially protective cytotoxic T cell responses. [ABSTRACT FROM AUTHOR]

We analyzed toxicity and efficacy of chemotherapy (CT) or second stem cell transplantation (SCT) and/or immunotherapy defined as stop of immunosuppression (IS) or donor leukocyte infusion (DLI) in 47 patients relapsing with acute leukemia. Ten patients received no treatment and 14 patients were treated with CT only. In 12 patients IS was stopped and three of them received additional CT. Five patients received DLI after CT as consolidation and one patient as frontline therapy. Five patients received a second SCT. Median overall survival after relapse was 2 months for the untreated patients, 2 months for patients receiving CT only, 2 months in patients after cessation of IS, 17 months in DLI treated patients and three months in patients receiving a second SCT. Fourteen patients achieved remission after relapse. Two with CT (2, 2 months), three with SI (3, 19, 19+ months), six with DLI (3, 8, 9, 14, 20, 36 months) and three with second SCT (2, 4, 6 months). Conventional CT was able do re-establish donor hematopoiesis and patients achieving remission showed a significantly better survival than patients with refractory disease. Patients who were brought into remission by DLI or cessation of IS had a significantly better survival than patients who achieved remission with CT alone or a second SCT. We conclude that a selected group of patients achieving remission with regeneration of donor hematopoiesis following CT might benefit from immunotherapy as consolidation. [ABSTRACT FROM AUTHOR]

Since deletion of chromosome 13q is a clinically relevant feature in multiple myeloma (MM), we analyzed bone marrow plasma cells from 29 patients with monoclonal gammopathy of undetermined significance (MGUS) to investigate the chromosome 13 status in MGUS. Studies were performed by interphase fluorescence in situ hybridization (FISH) with a panel of 13q14-specific probes (RB1, D13S319, D13S25, D13S31). Plasma cells with a deletion of at least one of the 13q14 loci were detected in 13 patients (44.8%) with MGUS. In five patients (17.2%), deletions of all four 13q14-specific probes were observed, and the additional deletion of a 13q telomeric region (D13S327) suggested loss of the entire 13q arm or monosomy 13. Loss of 13q14 was observed to be monoallelic and to occur in 11.0 to 35.0% of plasma cells (cut-off levels for a deletion <10% with all probes). Nine of 17 patients (52.9%) with MM progressing from a pre-existing MGUS had evidence for a deletion of 13q14 as determined by FISH with the RB1 probe. These results suggest that deletion of 13q14 is an early event in the development of monoclonal gammopathies, but its role for the eventual progression to MM remains to be determined prospectively. [ABSTRACT FROM AUTHOR]

The WT1 gene is expressed in 73-100% of patients with acute myelogenous leukemia (AML) and is thought to play a role in maintaining the viability of leukemic cells. WT1 has been proposed as a marker for minimal residual disease in leukemia. We obtained serial blood or bone marrow samples from patients with de novo AML at diagnosis, during therapy, and up to 95 months after diagnosis and analyzed for WT1 gene expression by RT-PCR to determine whether gene expression was predictive of relapse. Forty-four patients had WT1-positive AML and achieved a complete remission (CR) following chemotherapy and 24 patients underwent unrelated donor (n = 4), sibling donor (n = 13) or autologous (n = 7) marrow transplantation. After achieving CR 62% of the patients became WT1-negative, while 38% remained WT1-positive. There was no difference in the disease-free survival (DFS) and survival from remission between WT1-positive and -negative patients (P > 0.1). Following BMT, 32% of the patients analyzed in CR within the first 100 days after transplantation were WT1 PCR positive. Detection of WT1 transcripts within 100 days following BMT did not affect DFS and overall survival (OS) after transplantation (P > 0.1). Ten of 11 patients who are in continuous CR following chemotherapy or BMT for more than 3 years were transiently WT1-positive during the observation period. Four of these patients displayed the WT1 transcript at the last examination. Thirteen of 39 patients were WT1 PCR negative within 4 months before clinical onset of relapse and eight patients were WT1 PCR negative at time of relapse. These data indicate that: (1) achievement of WT1 negativity is not associated with longer DFS, survival from remission, or OS after transplantation; (2) not all patients who relapse become WT1 positive again; (3) long-term remitters frequently display the WT1 transcript. Thus, we conclude that the monitoring of WT1 gene expression by qualitative RT-PCR during treatment and CR is of very limited value. [ABSTRACT FROM AUTHOR]

Among 379 patients with AML with FAB type M1, 2 and M4-7 diagnosed between 1978 and 1997 in our institution, 19 (5%) had hypofibrinogenemia (HF), ie a fibrinogen level <180 mg/dl. Compared to patients with normal fibrinogen (n = 360) patients with HF had significantly elevated markers of activation of coagulation (TAT, F1.2, FPA) and fibrinolysis (D-dimer, FDP) indicating that disseminated intravascular coagulation/hyperfibrinolysis was the cause of hypofibrinogenemia. Patients with HF had significantly longer prothrombin times, thrombin clotting and reptilase times. Factor X and VIII were significantly lower than in patients without HF. With the exception of M7, HF occurred in all FAB subtypes, but was most common in M5 (12.1%). Patients with HF did not differ from those with normal fibrinogen with regard to age, sex, leukocyte count and other hematological parameters. During induction chemotherapy fibrinogen normalized rapidly (median 5 days) and there was no increased incidence of early hemorrhagic death. The overall and disease-free survival was similar to that of patients without HF. [ABSTRACT FROM AUTHOR]

We examined the presence of WT1-specific mRNA in bone marrow samples of 125 patients with de novo acute myeloid leukemia at diagnosis by two-step RT-PCR. The sensitivity of the assay was 1:100 (first step) and 1:10000 (second step), respectively. WT1-specific mRNA was detected in 73% of patients. No correlation was found between WT1 gene expression and age, FAB type, LDH and karyotype at diagnosis. All patients were treated with standard induction chemotherapy. There was no difference in the CR rate between WT1-positive and -negative patients. Using Kaplan and Meier plot analysis we found no difference in disease-free survival (DFS) and overall survival (OS) between patients displaying the WT1 transcript and WT1-negative patients. Furthermore, no significant interactions between WT1 PCR results and age, FAB type, LDH and karyotype on DFS and OS were demonstrable using Cox regression analysis. Eight patients who were WT1 PCR positive at diagnosis and achieved complete hematological remission following chemotherapy were monitored during the course of the disease. Based on our limited data demonstrating a heterogeneity of WT1 PCR results in CR we cannot draw any conclusions regarding the usefulness of WT1 PCR analysis for the early detection of relapse. We conclude that WT1 gene expression at diagnosis is not associated with specific characteristics of AML blast cells and is not a prognostic factor for CR, remission duration and overall survival in acute myeloid leukemia. [ABSTRACT FROM AUTHOR]

There is no doubt about 2-CDA being a very potent lymphotoxic agent that displays high efficacy in the treatment of CLL. It interferes with the intranuclear machinery of DNA regulation, and causes death to proliferative active, as well as resting lymphocytes. Interruption of crucial pathways that are evident for cell survival translates into high clinical response rates in CLL. CR and PR rates comparable to those reported on fludarabine are achieved in relapsed or refractory CLL. Even though trials on previously untreated CLL are still ongoing, a consistent trend towards durable, high CR rates becomes apparent. The toxicity is comparable to that of fludarabine and consists of infections, as well as thrombocytopenia. Clinical as well as in vitro studies suggest a crossresistance between the two purine analogues, indicating that sequential treatment is not useful. Given these data, although preliminary in case of de novo CLL, 2-CDA has to be recognized as one of the most effective cytostatic drugs currently available for CLL treatment. Large prospective trials (in comparison with fludarabine) will assess the role of 2-CDA as standard treatment. Such trials should also have the aim to substantiate the potential of 2-CDA as induction treatment followed by high-dose consolidation. [ABSTRACT FROM AUTHOR]