The expression of CD73 on pathological B-cells is associated with shorter overall survival of patients with CLL

CD73 is a membrane-bound enzyme that catalyzes the extracellular conversion of adenosine monophosphate to adenosine. Adenosine is thought to play a role in promoting tumor growth and survival together with suppressing the host immune responses, which contribute to the multistep process of tumorigenesis. Here, we studied the expression of this antigen in chronic lymphocytic leukemia (CLL). The expression of CD73 was analyzed by multiparametric flow cytometry on normal and pathological B-cells from peripheral blood and bone marrow samples from 71 patients with CLL. Pathological B-cells expressed significantly lower levels of CD73 than normal B-cells (p<0.01). Patients with splenomegaly showed a higher expression of CD73 on pathological B-cells than patients without splenomegaly (p<0.05). The expression of CD73 also correlated with beta-2-microglobulin levels (p<0.05). Clinically, patients with higher levels of CD73 versus those with lower expression presented with shorter overall survival (median OS of 65 vs. 113 months, p<0.05). Our data indicate that CD73 may play a role in CLL pathophysiology, is correlated with poor clinical and biological prognostic factors and may be of potential value as a prognostic marker and therapeutic target.

[Relation between Bcl-2 protein expression and results of therapy in patients with acute myeloblastic leukemia]

Flow cytometric expression of Bcl-2 protein was analyzed in 67 newly diagnosed acute myeloblastic leukemia (AML) patients using an anti-Bcl-2 monoclonal antibody by direct immunofluorescence technique and result were correlated with FAB subtype, CD34 expression and clinical outcome. The number of Bcl-2+ cells in each sample was heterogenous (range, 19% to 96%), with mean of 81%. The percentage of Bcl-2+ cells was higher in M0 and M1 types according French-American-British classification. The mean fluorescence index (MFI), expressed as the ratio of sample channel: control mean channel was significantly higher (p < 0.01) in M0 (19.0) and M1 (17.6) than M4 (11.7) and M5 (8.9) cytotypes. In addition, Bcl-2 MFI significantly correlated both with CD34 positivity and with CD34 MFI. High percentage expression of Bcl-2 and MFI index of Bcl 2 was associated with a low complete remission rate after intensive chemotherapy (40.4% in cases with 20% and more positive cells vs 72% in cases with less than 20% positive cells). By statistical analysis we also demonstrated that both Bcl-2 high MFI (> 16) and CD34 expression are independent prognostic factors for achieving CR in AML.

Efficiency of in vivo purging with autologous stem cell transplantation and monoclonal antibody in B-cell lymphomas

Elimination of tumor cells from hematopoietic stem cell products is a major goal of bone marow-suported high-dose cancer chemotherapy. In patients (pts) with low-grade lymphoma Gianni et al (2000) assessed the ability of Rituximab, given in combination with high-dose chemotherapy, to eradicate PCR-detectable disease and enable the harvesting of large amounts of uncontaminated circulating progenitor cells. Our study was conducted in 27 consecutive pts with untreated bcl2 positive NHL (follicular lymphoma--7, chronic lymphocytic leukemia--13 and NHL in leukemic phase--7), 14 pts received Rituximab. Patients received 4 courses of standard-dose chemotherapy (CHOP or FLU-CY), followed by one course of high-dose cyclophosphamid plus G-CSF. Patients allocated to Rituximab received i.v. infusions of 375 mg/m2 48 hours before stem cell collection and in 3 weekly doses after transplantation (R-CHT). Clinical response after transplantation was evaluated in 26 pts who completed the treatment. The complete response rate was in 100% in the Rituximab group (PCR negative in 79%) versus 50% of controls (p<0.01). Yield of purged CD34+ cells was with median 5.23x10(6)/kg in CHT and 8.76x10(6)/kg in R-CHT pts. Toxicity in the both arms was acceptated (no difference). No significant difference was observed between CHT and R-CHT group in the mean number of days spent with neutropenia and trombocytopenia. After a follow-up of 31 months, no patient relapsed. Aside from providing PCR-negative harvests, the chemoimmunotherapy treatment produced complete clinical (100%) and molecular remission in 79% of evaluable pts. We showed that Rituximab in combination with effective high-dose anti- lymphoma chemotherapy, allowed the harvesting of large amounts of tumor free progenitor cells in evaluable pts.

Fludarabine combined with cyclophosphamid is highly effective in the treatment of chronic lymphocytic leukemia

Combined treatment of fludarabine (FLU) with cyclophosphamide (CY) may increase the complete remission (CR) rate, decreased minimal residual disease (MRD) and, possibly, prolong survival in B-chronic lymphocytic leukemia patient's (B-CLL). The aim of study was to evaluate the activity and toxicity of FLU in combination with CY, the FLU-CY schedule, in patients with previously untreated B-CLL. From May 1999 to December 2002, 57 patients with advanced or progressive B-CLL received treatment with FLU at a dose of 30 mg/m2 for three consecutive days and CY at a dose of 300 mg/m2 for three days. The cycles were repeated at four week intervals or longer if severe myelosupression occurred. Guidelines for the evalution of response and toxicity were those developed by the National Cancer Institute Sponsored Working Group. Minimal residual disease (MRD) was detected by immunophenotyping only in patients with CR by standard criteria. In the analyzed group an overall response (OR) rate (CR+PR) of 89.5% (95% CI 80.6-94.7%) was achieved, including complete response in 29.8%. At the time of analysis 15 of 17 patients with CR are still in remission. Median duration of follow up in these is 12 (range 4-29.2) months. MRD was detected only in five out of 17(29.4%) patients with CR. Grade III/IV thrombocytopenia was seen in 3 (5.2%) patients and grade III/IV neutropenia in 6 (10.5%). Severe infections were noted in 14 (24%) patients. Two (3.5%) patients died, one due to sepsis, one as a result of disease progression. The FLU-CY regimen is highly effective combination in previously untreated CLL patients with acceptable toxicity. The efficacy of the regimen seems to be higher than that observed earlier after treatment with FLU alone.

Immune-mediated complications during interferon alpha therapy in chronic myelogenous leukemia

Several prospective randomized studies have shown that the treatment of chronic myeloid leukemia with interferon alpha (IFNalpha) prolongs the survival by comparison with conventional chemotherapy. However, long-term treatment with Interferon alpha can produce or exacerbate immune-mediated complications (IMC). The purpose of this study was to analyze the experience with IMC in patients with chronic myelogenous leukemia (CML) undergoing IFNalpha treatment. The occurrence of IMC was evaluated in 76 patients (47 male; 29 female) with Philadelphia chromosome (Ph)-positive CML. Diagnostic criteria of IMC were performed in patients with symptoms suggestive of particular disorders. Well-documented and clinically evident complications developed in 7 patients after a median of 19 months (range 1-84) of IFNalpha treatment. These included 9.2% patients with Ph-positive CML treated with IFNalpha-containing regimens. Hypothyroidism (H) occurred in 1 patient (1.3%), immune-mediated hemolysis (HEM) in 2 patients (2.6%) and connective tissue disorders (CTD) in 4 patients (5.3%) (2 systemic lupus erythematosus--SLE, 1 Raynaud's phenomena and 1 mixed connective tissue disease--MCTD). IFNalpha was discontinued in 3 patients and the dose was reduced in 2 patients. Five of 7 patients (75%) with immune-mediated complications had some degree of cytogenetic response at the time of the event. The association with female sex was strong and significant (86% vs 33.6%, x2; 48; p = 0.02). The frequency of IMC of clinical relevance with interferon alpha therapy in CML increased (long-term therapy). The patients treated with interferon alpha should be monitored for signs and symptoms of autoimmunity.

P-glycoprotein expression in adult acute myeloid leukemia: correlation with induction treatment outcome

Drug resistance has become a major cause of the treatment failure in patients with acute leukemia. P-glycoprotein (P-gp), which is associated with multidrug resistance (MDR) phenotype, has been reported to be an important predictor of the treatment outcome. The aim of this study was to analyze the value of P-gp expression in bone marrow cells as a predictor of the response to remission induction chemotherapy, as well as duration of remission in adult patients with newly diagnosed acute myeloid leukemia (AML). We examined the expression of P-gp in 31 patients using the monoclonal antibody UIC2. Direct immunofluorescent labeling was performed and samples were analyzed by flow cytomery. Kolmogorov-Smirnov test (D-value) was used to estimate UIC2 staining. A D > or = 0.3 for labeling of gated leukaemic blasts as compared to that of the isotypic control was defined positive (+) and compared to clinical data. P-gp expression was found in 14/31 (45.6%) patients, 17/31 (54.8%) of the samples were found P-gp negative(-). No correlation was found regarding age, sex and FAB subtype, altough 6/14 (43%) cases with more than 50% of cells having P-gp expression, were CD34+/CD7+. Complete remission rates were significantly lower in UIC2+ patients than in UIC2- cases (70% vs 35%, p < 0.01). Complete remission duration was also shorter in UIC2+ patients (6 vs 12.4 months). Our data indicate, that P-gp expression is a reliable marker of resistance to induction treatment in patients with de novo AML and can help to identify patients who may require alternative regimens designed to overcome therapy resistance.

Leukemic transformation of polycythemia vera after treatment with hydroxyurea with abnormalities of chromosome 17

The leukemogenic risk attributed to therapy of polycythemia vera with radiophosphorus and alkylating drugs has led, over the last 20 years, to the increased use of myelosupressive nonmutagenic drugs, especially hydroxyurea. But there exist reports, which showed the development of polycythemia vera into acute leukemia not only in patients treated with alkylating agents and radiophosphorus but also with single hydroxyurea. In this article we present two cases of polycythemia vera, in which the development to acute myeloblastic leukemia occurred after long-term treatment with hydroxyurea. Significant is the fact, that in both presented cases cytogenetic and FISH analysis showed abnormalities of chromosome 17, in the one of case fullfilled criteria for "17p-syndrome". Due to the possibility of leukemogenic potential in the time of hydroxyurea treatment, it is necessary to be careful especially in young patients. The dynamic follow up of cytogenetic analysis is necessary, especially, in those, where long-term hydroxyurea therapy is supposed.

Hematological and cytogenetic response of interferon alpha 2b alone and combined interferon alpha plus cytarabine as a first-line treatment in chronic myeloid leukemia

Treatment with interferon-alpha (IFNalpha) prolongs survival in chronic myeloid leukemia (CML). Additionally, cytarabine (AraC) can reduce the number of Ph + metaphases. Fortythree previously untreated patients with CML in chronic phase were randomly assigned to receive either. IFNalpha 2b (5 MU sqm/daily) or IFNalpha 2b in the same dosages plus monthly courses of low-dose AraC. The aim were complete hematologic remission at 6 months and cytogenetic response at 12 months. A complete hematologic remission occurred in 60.4% patients with single IFNalpha 2b in 76.2% patients with combination therapy. A cytogenetic response was present in 13.9% (major in 2 patients) with IFN therapy and in 38.1% patients with combination therapy. Two of 21 patients treated with IFNalpha/AraC therapy achieved major (9.52%), 4 partial (19.04%) and 2 minor (9.52%) cytogenetic response. Major side effects were cytopenia (20.1%), flu-like syndromes (42.4%) and increase of hepatic transaminases (3.4%). The side effects were more significant in the group receiving combination therapy. Based on published data that show a survival advantage for patients who achieved any cytogenetic response, and high rate of cytogenetic response which we observed in our study we believe that IFN plus AraC regimen could be a front-line therapy for CML.

[Hematologic and cytogenetic response to treatment in patients with chronic myeloid leukemia]

BACKGROUND

The Interferon alpha therapy increases the number of cytogenetic responses in patients with chronic myeloic leukaemia. The addition of cytarabine can reduce the number of Ph positive metaphases. The achievement of cytogenetic response is connected with longer survival of patients with chronic myeloic leukaemia. The aim of the study was the evaluation of the achievement of hematologic and cytogenetic response as well as adverse effects of the treatment in chronic myeloic leukaemia patients.

METHODS AND RESULTS

The followed was the group of 87 previously untreated CML Ph positive patients. 34 patients with the median age of 44.6 years were treated with hydroxyurea, 42 patients were treated with single interferon alpha and 11 patients with the median age of 41.3 years with the combined interferon plus cytarabine therapy. The complete hematologic remission occurred in only 17.5% of patients treated with hydroxyurea, but in 35.7% treated with interferon and in 54.5% patients treated with the combined therapy. The cytogenetic response we have not found in any of hydroxyurea treated patients, in the group of interferon alpha in 38%. The highest number of cytogenetic responses was in the group treated with interferon plus cytarabine. As we have expected, the addition of cytarabine increased hematotoxicity and gastrotoxicity.

CONCLUSION

Based on the published date, that show a better survival of patients with the achieved cytogenetic response as well as the higher number of cytogenetic responses in the group of interferon plus cytarabine therapy from our observation, we believe, that combined therapy should be suitable as a front-line therapy of chronic myeloic leukaemia patients.

[The 6M 12M trial--study of the effectivess and tolerance of treatment in chronic myeloid leukaemia with a combination of interferon alfa and cytarabine]

OBJECTIVE

Comparing the conventional treatment after the interferon alpha treatment the number of hematologic as well as cytogenetic responses increases. With the cytogenetic response is associated a longer survival. Today is interferon alpha considered to be the first line treatment in those patients with chronic myeloic leukaemia, who are not candidates for alogenic bone marrow transplantation. The combination with cytosinarabinoside can reduce the number of Ph positive metaphases.

DESIGN AND METHODS

Forty-three previously untreated patients with CML in chronic phase were randomly assigned to receive either IFN alpha 2 b (5MU sqm/daily) or IFN alpha 2 b in the same dosage plus monthly courses of low-dose AraC. The aim were complete hematologic remission at 6 months and cytogenetic response at 12 months.

RESULTS

A complete hematologic remission occured in 61.9% patients with single IFN alpha 2 b and in 78.9% patients with combination therapy. A cytogenetic response was present in 28.5% and in 42.2% patients with combination therapy. One of 21 patients treated with IFNalpha/AraC therapy achieved complete (5.2%), 4 partial (21%) and 3 minor (16%) cytogenetic response. The side effects were more significant in the group receiving combination therapy.

CONCLUSIONS

Based on published data that shows a survival advantage for patients who achieved any cytogenetic response and high rate of cytogenetic response which we observed in our population we believe that IFN plus AraC regimen could be a front-line therapy for CML.

[Recombinant interferon alfa in the treatment of essential thrombocythemia]

Essential thrombocythaemia, a clonal myeloproliferative disease characterized by a persisting increase of the number of thrombocytes, their abnormal morphology and function, is a special clinical and therapeutic problem which calls for a comprehensive approach. Based on a group of their own patients and on data from the literature, the authors discuss the asset of interferon alpha in the treatment of essential thrombocythaemia.

[Interferon alpha in the treatment of chronic myeloid leukemia]

The authors present their results assembled in patients with chronic myeloid leukaemia (CML) to whom they administered interferon alpha (IFN) in the chronic stage of the disease. They evaluated the survival of patients and the haematological and cytogenetic response. They recorded a favourable haematological response in patients with CML to IFN treatment comparable with data reported in the literature. They assume that the smaller number of cytogenetic responses is due to the smaller percentage of patients in the early chronic stage and short period of hydroxyurea administration at the onset of treatment. They consider interferon alpha, similarly as other authors, a successful drug in the treatment of the chronic stage of chronic myeloid leukaemia.