Biomedical subjects

M Beran

Publications and source records attributed to M Beran.

At least 91 records · Page 5Linked to original sources

PubMed1995

Philadelphia chromosome-negative chronic myelogenous leukemia with rearrangement of the breakpoint cluster region. Long-term follow-up results.

BACKGROUND: Five to 10% of patients with chronic myelogenous leukemia (CML) do not have the Philadelphia chromosome (Ph), but one-third of them have rearrangements of the breakpoint cluster region (BCR-positive). METHODS: The authors analyzed the characteristics, treatment response, and prognosis of 23 patients with BCR-positive, Ph-negative CML, and compared them with patients with Ph-positive CML, Ph-negative BCR-negative CML and chronic myelomonocytic leukemia (CMML) treated during the same period. RESULTS: Seventeen patients had early chronic phase CML, 3 had late chronic phase, 2 had accelerated phase, and 1 had blastic phase. The median age was 44 years (range, 14-71 years), median platelet count was 402 x 10(9)/l, and median leukocyte count was 86 x 10(9)/l. Fourteen of the 17 patients with early chronic phase CML received alpha-interferon; 12 (86%) achieved complete hematologic remission. Median survival in chronic phase CML was 60 months (range, 3-90+ months). Patients with Ph-negative BCR-positive CML and those with Ph-positive CML had similar characteristics and outcome. Compared with patients with Ph-negative BCR-negative CML and CMML, patients with Ph-negative BCR-positive CML and Ph-positive CML were significantly younger, had a significantly higher incidence of leukocytosis, thrombocytosis, and peripheral and marrow basophilia, and a significantly lower incidence of anemia, thrombocytopenia, marrow blast percent, and peripheral and marrow monocytosis. The median survival was 60 months for Ph-negative BCR-positive CML, 73 months for Ph-positive CML, 25 months for Ph-negative BCR-negative CML, and 9 months for CMML (P < 0.001). When analyzed adjusting for their stage, patients classified with Ph-negative BCR-positive CML. Stage I disease had a significantly better survival than did patients with Ph-negative BCR-negative CML (P < 0.02). CONCLUSIONS: Patients with Ph-negative BCR-positive CML are similar to those with Ph-positive CML and should be treated with the same approaches.

Adolescent↗

PubMed1995

Glycaemic activity of (III)-beta-nicotinamide adenine dinucleotide phoshate complex and its presence in yeast extracts.

Two main stable chromium complexes were detected in the aqueous extract of Cr-rich yeast using high-performance liquid chromatographic (HPLC) separation on a reversed-phase RP-8 column and atomic absorption spectrometric detection of chromium. However, the complexes could not be separated and purified sufficiently to allow their reliable identification. Both complexes behaved like ionic or very polar substances with a weak affinity to the reverse-phase column. Yeast extract was then spiked with some synthetic Cr complexes which were prepared considering known data (UV spectra, molecular mass, etc.) on candidates glucose tolerance factor (GTF) compounds. Among the complexes tested, attention was paid especially to the complex of Crm with beta-nicotinamide adenine dinucleotide phosphate (NADP), which accompanies one of two Cr complexes in yeast extract during the HPLC separation. The complex with a Cr:NADP stoichiometric ratio 1:2 has not previously been reported. The complex was tested for its glycaemic activity using glucose tolerance test on rabbits. Significant hyperglycaemia was caused in the animals. Considering the NADP is generally present in tissues of nearly all living organisms, its complexes with transient metals could play a very important role in oxidation-reduction processes of metabolic pathways.

Animals↗

PubMed1995

Fludarabine plus doxorubicin in previously treated chronic lymphocytic leukemia.

Based on the activity of fludarabine and doxorubicin in chronic lymphocytic leukemia (CLL), 30 patients received this combination. The median age of these patients was 61 years; median Zubrod performance status was one; median number of prior therapies was three; and median time to treatment was 53 months. Rai stage was 0 for two patients, I/II for 19 patients, and III/IV for nine patients. Prior treatment included fludarabine in 25 patients. In this regimen, fludarabine was administered as 30 mg/m2/d IV x 3 to 10 patients, 25 mg/m2/d IV x 4 to three patients, and to 17 patients as 30 mg/m2/d IV x 4. A 50 mg/m2 IV dose of doxorubicin was given to all patients. The first 17 patients received prednisone 30 mg/m2 x 5 days; however, this was discontinued due to other data demonstrating no therapeutic advantage and increased opportunistic infections when corticosteroids were added to fludarabine. Toxicity consisted primarily of infectious episodes: pneumonia nine, bacteremia one, FUO seven, and minor infection five. Two deaths from pneumonia occurred. Standard guidelines for response were used with the addition of a nodular CR group. Despite prior treatment with fludarabine in the majority of patients, the response rate in the 29 evaluable patients was CR 3%, nodular CR 17%, PR 35%, fail 38% and early death 7%. This combination of fludarabine and doxorubicin is active against CLL and warrants further study.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1995

A 3-day schedule of fludarabine in previously treated chronic lymphocytic leukemia.

This study was undertaken to determine the efficacy and toxicity of a shorter schedule of fludarabine administration (30 mg/m2 i.v. daily for 3 days every 4 weeks) in patients with previously treated chronic lymphocytic leukemia (CLL). Eighty patients with previously treated advanced (Rai III-IV) (54%) or progressive Rai stage 0-II (46%) were treated. The results of this trial were retrospectively compared with those of previous fludarabine trials using different schedules of administration. The complete response (CR), nodular CR and partial response rates were 10, 15 and 21%. The overall response rate (46%) was slightly lower than prior regimens using a 5-day schedule of fludarabine; however, this difference was not significant. Further evaluation by dual-parameter flow cytometry and immunoglobulin gene rearrangement analysis revealed that minimal residual disease was more common in a 3-day schedule. The overall incidence of infections per treatment course (14%) was significantly lower than that observed on the 5-day or weekly regimens (P < 0.001). The incidence of minor, atypical and viral infections were similar. There was no difference in survival in the various trials. In conclusion, a 3-day schedule of fludarabine in previously treated CLL patients was associated with a lower infection rate and similar survival to a 5-day schedule. These data support the use of a 3-day schedule of fludarabine as a single agent and in combination with other active agents.

Adult↗

PubMed1995

High remission rate, short remission duration in patients with refractory anemia with excess blasts (RAEB) in transformation (RAEB-t) given acute myelogenous leukemia (AML)-type chemotherapy in combination with granulocyte-CSF (G-CSF).

A study was made to determine CR rate, response duration and survival in patients with RAEB or RAEB-t given AML-type chemotherapy, in particular the newer agents idarubicin and fludarabine. Eighty-five adults (58 RAEB-t, 27 RAEB) received either IA (idarubicin 12 mg/m2 daily on days 1-3, ara-C 1.5 g/m2 daily on days 1-4 CI), FA (fludarabine 30 mg/m2 daily on days 1-5, ara-C 2 g/m2 daily on days 1-5) or FLAG (FA + G-CSF 400 micrograms/m2 daily from day-1 until CR). IA was given exclusively to patients with better prognosis (as assessed by pretreatment karyotype), while FA and FLAG were given first to patients with worse and then to those with better prognosis. In remission, patients received lower doses of the same regimens for 6-12 months. The 85 patients comprise the largest reported series of RAEB or RAEB-t patients given AML-type chemotherapy. Their median age was 61 years, 33% had chromosome 5 or 7 abnormalities (-5/-7), and 55% were treated in laminar air flow rooms. The CR rate was 66%. While rates were highest in younger patients with a normal karyotype, CR rates in excess of 50% were also obtained in patients over age 60 (27/47; 57%) and in patients with -5/-7 (17/29; 59%). In 11 of the 14 cytogenetically abnormal patients in whom cytogenetic analysis was repeated at the time of CR, only normal metaphases were found. In the remaining 3 the number of abnormal metaphases was substantially reduced. However, the probability of continued CR was low (e.g. 452 +/- 0.08 at 12 months), and the only patients alive in CR beyond two years were patients under age 60 without -5/-7 and with RAEB-t. Survival probability was 0.35 +/- 0.05 at one year. Eight of 56 patients died in CR. While current AML-type chemotherapy can produce higher CR rates than is perhaps usually appreciated, in some patients with RAEB or RAEB-t (e.g. older patients with -5/-7) the brevity of the remissions and the risk entailed suggest that new post-remission therapies are needed to make this approach generally worthwhile.

Adult↗

PubMed1994

Levels of retinoblastoma protein expression in newly diagnosed acute myelogenous leukemia.

The relationship between the level of retinoblastoma protein (RB) expression and the survival of 113 newly diagnosed acute myelogenous leukemia (AML) patients was studied. Western blotting was used to determine the level of RB protein present in peripheral blood leukemia cells and results were confirmed in 26 patients by immunohistochemistry. The leukemic cells from 22/113 AML patients (19%) contained RB protein at levels that were equal to or less than the level of RB observed in the mononuclear cell fraction of peripheral blood from normal individuals (Low RB). Levels of RB greater than that of normal blood (Elevated RB) were seen in 91 patients (81%). The median survival of patients with low RB was significantly shorter than that seen in patients with elevated RB, 12 weeks versus 40 weeks (P = .02). Remission induction frequency was 36% in low RB patients compared with 68% in AML patients with elevated RB (P = .01). Multivariate analysis showed that low RB protein level was an independent prognostic factor predictive or poor survival after allowing for other known prognostic factors. These data suggest that a low level of the RB protein at the time of diagnosis is associated with shortened survival in AML patients because of inferior response to conventional therapy. Monitoring of the RB level could identify a subgroup of AML patients with an extremely poor prognosis when treated with chemotherapy alone, who would be eligible for alternative therapeutic strategies.

Adolescent↗

PubMed1994

Lack of effect of 2-chlorodeoxyadenosine therapy in patients with chronic lymphocytic leukemia refractory to fludarabine therapy.

BACKGROUND: Fludarabine and 2-chlorodeoxyadenosine are nucleoside analogues that have proved effective in patients with chronic lymphocytic leukemia (CLL). Although their mechanism of action is thought to be similar, a small number of patients who do not respond to fludarabine do respond to 2-chlorodeoxyadenosine. The extent to which 2-chlorodeoxyadenosine is effective in patients who do not respond to fludarabine is not known, however. METHODS: We treated 28 patients with CLL refractory to fludarabine therapy with a continuous infusion of 2-chlorodeoxyadenosine at a daily dose of 4 mg per square meter of body-surface area for seven days. The treatment could be repeated monthly. The number of treatments ranged from one to five; patients who responded continued to receive treatment until the maximal response was achieved. RESULTS: Two patients (7 percent) had partial remissions, but no patients had complete remissions. One other patient had a substantial response but had residual thrombocytopenia. The rate of response in most affected organs was 20 percent, but anemia or thrombocytopenia rarely improved. Myelosuppression was frequent, and 65 percent of the courses of 2-chlorodeoxyadenosine therapy were accompanied by febrile episodes or infections. Ten patients died within 60 days of starting therapy with 2-chlorodeoxyadenosine; eight deaths were related to infection. The median platelet count at the start of 2-chlorodeoxyadenosine therapy in these 10 patients was 24,000 per cubic millimeter, as compared with 109,000 per cubic millimeter in the other 18 patients. Five patients were alive after a median follow-up of 24 months. CONCLUSIONS: Patients with advanced CLL refractory to fludarabine therapy are unlikely to benefit from treatment with 2-chlorodeoxyadenosine. Although 20 percent of the patients have some response, thrombocytopenia and anemia are rarely corrected and may be made worse by 2-chlorodeoxyadenosine therapy.

Adult↗

PubMed1994

Philadelphia-chromosome-positive adult acute lymphocytic leukemia: characteristics, treatment results, and prognosis in 41 patients.

BACKGROUND: Philadelphia-Chromosome-positive (Ph-positive) acute lymphocytic leukemia (ALL) is associated with poor outcome in children as well as in adults. We report our experience in patients with Ph-positive ALL and review their clinico-laboratory characteristics, response to different therapies, and overall prognosis. PATIENTS AND METHODS: Since 1980, 41 newly diagnosed patients with Ph-positive ALL were referred to our service. In addition to confirmation of their diagnosis by morphologic studies of bone marrow aspiration and biopsy specimens, patients underwent cytogenetic, immunophenotypic, and molecular studies. Thirty-five patients received vincristine-Adriamycin-dexamethasone (VAD) or cyclophosphamide (CVAD) induction regimens, and 6 patients were treated with other combinations. Thirty-seven patients received salvage therapy that included VAD, high-dose cytosine arabinoside (ara-C)-containing regimens, methotrexate-asparaginase, and high-dose chemotherapy with autologous or allogeneic bone marrow transplantation (BMT). RESULTS: The 41 patients were among 334 patients with ALL (12%) seen during that same period. Patients with Ph-positive ALL were older and had a significantly lower incidence of anemia and a higher incidence of peripheral leukocytosis, FAB L2 (French-American-British) morphology, common acute lymphocytic leukemia antigens (CALLA), and CD34 marker positivity. With induction chemotherapy, 23 of 41 Ph-positive ALL patients (56%) achieved complete remission, and their median survival and remission duration were 11 months and 9 months, respectively. Thirteen of 31 Ph-positive ALL patients (42%) achieved complete response with high-dose ara-C regimens during salvage therapy. CONCLUSIONS: In our experience, patients with Ph-positive ALL are usually older, have FAB L2 morphology, and are CALLA-positive and CD34-positive. These patients have a poor prognosis when treated with conventional approaches with lower overall complete response rate, shorter remission duration, and shorter survival. There appears to be a selective sensitivity to high-dose ara-C in these patients that suggests a possible role of this agent as part of early consolidation or induction regimens.

Adult↗

PubMed1994

Acute lymphocytic leukaemia in the elderly: characteristics and outcome with the vincristine-adriamycin-dexamethasone (VAD) regimen.

To analyse the pretreatment characteristics, response to therapy, and overall prognosis of elderly patients with acute lymphocytic leukaemia (ALL), 268 consecutive adults with newly-diagnosed ALL who received the vincristine-adriamycin-dexamethasone (VAD) regimens were reviewed. Pretreatment characteristics, response to VAD therapy, and overall outcome were analysed in patients 60 years or older, and compared to younger patients. Fifty-two patients (19%) were 60 years or older. Compared with younger patients, elderly patients with ALL had a significantly worse performance status at presentation (P < 0.001); higher incidences of FAB L2 morphology (P = 0.03), thrombocytopenia (P < 0.01), hypoalbuminaemia (P < 0.001) and renal dysfunction (P = 0.03); and trends for worse anaemia (P = 0.06) and a higher rate of myeloid markers positivity (P = 0.06). With VAD induction therapy, elderly patients had a lower CR rate than younger patients following two induction courses (CR rate 58% v 82%; P < 0.01), and overall (CR rates 65% v 90%; P < 0.01). The response rate to VAD chemotherapy, however, appeared superior to the 30-35% CR rates reported from other series in elderly ALL patients. The lower CR rate was due to both higher induction mortality (P = 0.02) and more resistant disease (P < 0.01). The long-term CR rate was 20% in elderly patients achieving CR, but the overall survival was poor (< 10% at 3 years). There were strong associations between older age and other poor prognostic features. However, multivariate analyses identified older age to be an independent poor prognostic factor for response to chemotherapy. In summary, elderly patients with ALL have an appreciable CR rate with the VAD regimens. Patients achieving CR may have durable remissions. The myelosuppression-associated mortality in both remission induction and maintenance may be reduced with the addition of growth factors in both treatment phases, and by using standard maintenance therapy without consolidation-intensification phases.

Age Factors↗

PubMed1994

Use of granulocyte colony-stimulating factor before, during, and after fludarabine plus cytarabine induction therapy of newly diagnosed acute myelogenous leukemia or myelodysplastic syndromes: comparison with fludarabine plus cytarabine without granulocyte colony-stimulating factor.

PURPOSE: To determine whether granulocyte colony-stimulating factor (G-CSF) administered before, during, and after fludarabine plus cytarabine (ara-C; FA) chemotherapy affected complete response (CR) rate, infection rate, blood count recovery, or survival in patients with newly diagnosed acute myelogenous leukemia (AML) or myelodysplastic syndromes (MDS). PATIENTS AND METHODS: A total of 112 patients with newly diagnosed AML (n = 69) or MDS (n = 43) received G-CSF 400 micrograms/m2/d 1 day before (presenting WBC count < 50,000/microL) and/or during (all patients) fludarabine 30 mg/m2/d and ara-C 2 g/m2/d for 5 days (FLAG). G-CSF continued until a CR was achieved. Results were compared with those in 85 newly diagnosed patients (54 AML, 31 MDS) previously treated with FA without G-CSF. RESULTS: Patients in both groups were relatively old (median age of all patients, 63 years), and were likely to have prognostically unfavorable cytogenetic abnormalities (36% had abnormalities of chromosomes 5 and 7 [-5/-7]). G-CSF accelerated recovery to > or = 1,000 neutrophils (P < .0001; median, 34 days for FA, 21 days for FLAG), but logistic regression provided no evidence that the CR rate was higher with FLAG than with FA (P = .50), with unadjusted CR rates of 63% and 53%, respectively. This may reflect relatively high rates of death before neutrophil recovery in both groups. Rates of infection were similar in both groups. The follow-up duration in remission is short, and much of these data remain censored. To date, survival is similar with FA and FLAG. CONCLUSION: On average, G-CSF before, during, and after FA had no effect on CR or infection rates in this population, in which elderly patients and poor prognostic factors were prevalent. The use of FA and laminar airflow rooms rather than more usual therapy needs to be considered when analyzing the results.

Aged↗

PubMed1994

Growth of sensitive and drug-resistant human myeloid leukemia cells in SCID mice.

Drug resistance is a critical problem in the therapy of hematologic malignancies. Recent advances in the transplantation of human normal and transformed hematopoietic cells into severe combined immunodeficient (SCID) mice provide an opportunity to study the biologic and molecular events that mediate resistance. We studied the engraftment of several human myelogenous leukemia cell lines sensitive and resistant to amsacrine (mAMSA), vincristine, hycamptamine, methotrexate, or doxorubicine (KBM3/AMSA, K562/Vcr, HL60/Hy10, K562/MTX, HL60/Dox). The distribution and growth potential of these cells was evaluated using molecular and histologic techniques. Inoculation of 2 x 10(7) leukemic cells led to manifestation of disease, and subsequent tissue analysis showed evidence of leukemia. The survival of mice varied from 21 to 135 days. Terminally, the animals showed symptoms of wasting, development of local tumors, or both. Massive leukemic dissemination with infiltration of bone marrow and various organs including lungs, spleen, liver, ovaries, and brain was detected in most cases. No differences were observed in the tissue distribution of sensitive as compared to resistant leukemia cells. These findings demonstrated that human leukemic cells retain, in SCID mice, the clinico-pathologic picture of the original disease in humans. The development of numerous drug-resistant phenotypes in vitro does not alter the subsequent behavior of resistant cells in vivo when compared with sensitive counterparts. The levels of resistance are not modified by passage through SCID mice. This model offers an opportunity for developing new preclinical in vivo systems for modulation of drug resistance, and the combination of this in vivo model with gene transfer methods will also provide an important system for testing the molecular alterations involved in drug resistance and leukemic progression.

Acute Disease↗

PubMed1993

Granulocyte colony-stimulating factor supportive treatment following intensive chemotherapy in acute lymphocytic leukemia in first remission.

BACKGROUND: The efficacy of granulocyte colony-stimulating factor (G-CSF) in reducing neutropenia and its associated complications in adults with acute lymphocytic leukemia (ALL) undergoing intensive chemotherapy in first remission was evaluated. METHODS: Fourteen adult patients with ALL in first remission received intensive chemotherapy consisting of mitoxantrone 5 mg/m2 intravenously (IV) over 1 hour daily for 3 days, cytosine arabinoside (ara-C) 3 g/m2 IV over 2 hours every 12 hours x 4 on days 1 and 2, vincristine 2 mg IV on day 1, solumedrol 50 mg IV twice daily for 5 days, and G-CSF 5 micrograms/kg subcutaneously daily starting on day 4 until granulocyte recovery. Their outcome was compared with that of 14 consecutive patients who received the same intensification chemotherapy, but without G-CSF. The latter patients had been entered on the same ALL protocol from April 1990 through June 1991. RESULTS: G-CSF administration was associated with a significant shortening in the duration of neutropenia. The number of days to granulocyte recovery above 0.5 x 10(3)/microliters was 14 in the G-CSF group versus 18 days in the historical group (P < 0.001). Two episodes of documented infections were observed in the G-CSF group compared with four episodes in the historical group. Death during intensification therapy occurred in 2 of 14 patients in the historical group, but in none of the 14 patients receiving G-CSF. CONCLUSIONS: G-CSF as an adjunct to intensive chemotherapy in adults with ALL in first remission yielded positive results. Future studies incorporating growth factors supportive care during remission, induction, and consolidation may reduce treatment-related morbidity and mortality, increase the dose-intensity delivery of therapy, and potentially improve patient outcome.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1993

Fludarabine and cytosine arabinoside in the treatment of refractory or relapsed acute lymphocytic leukemia.

BACKGROUND: The objectives of the study were to evaluate the antileukemic efficacy and toxicity profiles of the combination of fludarabine and intermediate-dose cytosine arabinoside (ara-C) in refractory or relapsed adult acute lymphocytic leukemia (ALL). PATIENTS AND METHODS. Thirty adults with refractory or relapsed ALL were treated. Their median age was 45 years, 60% were in second or subsequent relapse, and 37% had Philadelphia chromosome-positive disease. Treatment consisted of ara-C 1 g/m2 during a period of 2 hours daily for 6 days, and fludarabine 30 mg/m2 during a period of 30 minutes daily for 5 days on days 2-6. Fludarabine was given 4 hours before ara-C to increase the rate of ara-C 5'-triphosphate (ara-CTP) accumulation in leukemic cells. Courses were repeated every 3 weeks or longer, depending on patient response and side effects. RESULTS: Nine (30%) patients achieved a complete remission (CR), 8 (27%) died during remission induction, and 13 (43%) had resistant disease. The median CR duration was 22 weeks, and the median survival was 12 weeks for all patients, and 34 weeks for those who had a response to treatment. Except for low platelet counts, which predicted shorter survival time, no other prognostic factors were demonstrated, considering the small number of patients treated. Myelosuppression-associated febrile episodes were the most common side effects, occurring in 28 (93%) patients. Neurotoxicity was noted in two (7%) patients. CONCLUSIONS: Fludarabine and ara-C are an active and relatively safe antileukemic combination in refractory or relapsed ALL. Future studies will incorporate other anti-ALL agents, such as topoisomerase II-reactive drugs, to improve the overall efficacy, and growth factors, to reduce myelosuppression-related complications.

Adult↗

PubMed1993

Results of fludarabine and prednisone therapy in 264 patients with chronic lymphocytic leukemia with multivariate analysis-derived prognostic model for response to treatment.

Two hundred sixty-four patients with chronic lymphocytic leukemia were treated with fludarabine 30 mg/m2 intravenously for 30 minutes each day for 5 days and with prednisone 30 mg/m2 orally each day for 5 days. Courses were repeated monthly. Of the 264 patients. 125 patients (47%) had Rai stage III-IV disease; 169 patients (64%) were previously treated with a median of 3 prior regimens; and 138 of them (82%) were refractory to therapy with alkylating agents. The overall response (OR) and complete response (CR) rates in the 169 previously-treated patients were 52% and 37%; these were 74% and 63%, respectively, in Rai stage O-II patients and declined to 64% and 46%, respectively, in Rai III-IV disease. Among the previously untreated patients, the OR and CR rates were 79% and 63%, these being 85% and 70%, respectively, in Rai O-II patients, and declining to 64% and 46%, respectively, in Rai III-IV disease. The incidence of minor infections or fever of unknown origin was similar in all patient groups and occurred in 22% of courses. The incidence of sepsis and/or pneumonia was significantly correlated with the extent of prior therapy and with Rai stage, and ranged from 3% of courses in the previously untreated Rai O-II patients, to 13% of courses in the previously treated Rai III-IV patients. Listeria sepsis or Pneumocystis carinii pneumonia was noted in 14 patients. With therapy, CD4 levels were uniformly depressed from a median 1,015/microL pretreatment to a median 159/microL after 3 months of fludarabine therapy. Median time to progression in previously treated patients was 22 months. In previously untreated patients, median time to progression was 30 months for patients who achieved a partial remission and has not been reached in patients who achieved a CR with a median follow-up of 2 years. The median survival was 18 months for previously treated patients and has not been reached for previously untreated patients. Response rates in previously treated and untreated patients, as well as infection rates, were identical to those seen in 110 patients treated with the same dose schedule of fludarabine alone. Logistic regression analysis selected 4 factors to be significantly associated with worse response: Rai III-IV stage disease, prior therapy, older age, and low albumin levels. The regression equation was used to derive a probability of response based on the 4 characteristics. When the model was applied to the same population, patients could be divided into 4 prognostic groups with different outcomes.

Antigens, CD↗

PubMed1993

Biological properties and growth in SCID mice of a new myelogenous leukemia cell line (KBM-5) derived from chronic myelogenous leukemia cells in the blastic phase.

The establishment and the biological properties of a new leukemic cell line (KBM-5) derived from a patient in the blastic phase of chronic myelogenous leukemia are described. The cells exhibited multiple copies of the Philadelphia chromosome, and a high level of p210Bcr-Abl kinase activity was detected with rabbit anti-Abl and anti-Bcr (exon 3) peptide antisera. Use of specific primers and polymerase chain reaction followed by Southern blotting revealed that KBM-5 cells carried a bcr3-ABLII splice junction. While a normal BCR message was detected, no normal ABL message was found. The cells were phenotypically myeloid with monocytic differentiation. The high cloning efficiency in semisolid media was independent of the presence of exogenous colony-stimulating factors. In vitro exposure to induces of differentiation, such as retinoic acid, dimethyl sulfoxide, or hemin, failed to influence the growth rate of the cells and their level of differentiation. KBM-5 cells are highly resistant to the antiproliferative action of recombinant alpha- and gamma-interferons. Although sensitive to recombinant tumor necrosis factor alpha, they were completely resistant to natural killer cell action. KBM-5 cells constitutively expressed mRNA for tumor necrosis factor alpha but not for gamma-interferon, other interleukins, or hematopoietic growth factors. The KBM-5 cells that were transplanted into SCID mice manifested metastatic potential and tissue invasiveness similar to the way leukemic cells in humans do. This new KBM-5 cell line represents a helpful model for examining in vitro and in vivo modulation of the growth and properties of leukemic cells by using biological and chemotherapeutic agents.

Aged↗

PubMed1993

Long-term follow-up of patients with chronic lymphocytic leukemia treated with fludarabine as a single agent.

The clinical response and survival of 113 patients with at least 3-year follow-up after treatment with fludarabine as a single agent for chronic lymphocytic leukemia has been evaluated. Seventy-eight patients were previously treated and 35 were untreated. The response to therapy and survival were strongly correlated with the degree of previous therapy, the stage of disease, and whether or not the patients were refractory to alkylating agents. Other characteristics associated with survival were the age of the patient and the serum albumin level at the start of therapy. The median time to progression of responders who had not received prior therapy was 33 months and was 21 months for previously treated patients. Survival after progression of disease was also strongly correlated with the degree of prior therapy. No successful salvage regimen after initial fludarabine therapy was shown for patients refractory to alkylating agents, although fludarabine achieved further remissions in patients who had received fludarabine as their initial treatment or were not refractory to alkylating agents. The morbidity of patients in unmaintained remission on discontinuation of fludarabine was low, with less than one episode of infection per patient-year at risk. The morbidity during this time was correlated with clinical response and whether the patients had received prior therapy. Although fludarabine is a very effective cytoreductive regimen, most patients, including those who achieved true complete remissions, will have recurrent disease. Longer follow-up and comparative trials are required before the effect of fludarabine on survival is shown.

Adult↗

PubMed1993

Phase I study of Topotecan, a new topoisomerase I inhibitor, in patients with refractory or relapsed acute leukemia.

The purpose of this study was to define, in a phase I study in leukemia, the maximally tolerated dose (MTD), major toxicities, and possible antitumor activity of Topotecan, a new topoisomerase I (topo I) inhibitor. Topotecan was delivered by a 5-day continuous infusion every 3 to 4 weeks to patients with refractory or relapsed acute leukemia, at doses ranging from 3.5 mg/m2 to 18 mg/m2 per course. Twenty-seven patients were treated, including 17 patients with acute myelogenous or undifferentiated leukemia, 7 with acute lymphocytic leukemia, and 3 with chronic myelogenous leukemia in blastic phase. Severe mucositis was the dose-limiting toxicity occurring in two of five patients treated with Topotecan 11.8 mg/m2 per course; a third patient had prolonged myelosuppression. At the MTD of 10 mg/m2 per course, 1 of 12 patients had severe mucositis and 5 had mild-to-moderate mucositis. Nausea, vomiting, diarrhea, and prolonged myelosuppression were uncommon. Three patients (11%) achieved a complete response, two (7%) had a partial response, and one (4%) had a hematologic improvement. The overall complete plus partial response rate was 19%, and 24% in acute myelogenous or undifferentiated leukemia. A novel in vitro assay that quantifies Topotecan-stabilized topo I-DNA complexes in patient samples was used, which demonstrated heterogeneity in the ability of Topotecan to interact with topo I, the intracellular target of Topotecan. This phase I study defined the MTD of Topotecan to be 10 mg/m2 by continuous infusion over 5 days every 3 to 4 weeks in patients with refractory or relapsed acute leukemia. Severe mucositis was the dose-limiting toxicity. Future studies will define the precise activity of Topotecan in different leukemia subsets, its efficacy in combination with other antileukemic drugs, and correlations between Topotecan-induced topo I-DNA complex formation and individual patient response to Topotecan.

Acute Disease↗

PubMed1993

Subcellular localization of Bcr, Abl, and Bcr-Abl proteins in normal and leukemic cells and correlation of expression with myeloid differentiation.

We used specific antisera and immunohistochemical methods to investigate the subcellular localization and expression of Bcr, Abl, and Bcr-Abl proteins in leukemic cell lines and in fresh human leukemic and normal samples at various stages of myeloid differentiation. Earlier studies of the subcellular localization of transfected murine type IV c-Abl protein in fibroblasts have shown that this molecule resides largely in the nucleus, whereas transforming deletion variants are localized exclusively in the cytoplasm. Here, we demonstrate that the murine type IV c-Abl protein is also found in the nucleus when overexpressed in a mouse hematopoietic cell line. However, in both normal and leukemic human hematopoietic cells, c-Abl is discerned predominantly in the cytoplasm, with nuclear staining present, albeit at a lower level. In contrast, normal endogenous Bcr protein, as well as the aberrant p210BCR-ABL and p190BCR-ABL proteins consistently localize to the cytoplasm in both cell lines and fresh cells. The results with p210BCR-ABL were confirmed in a unique Ph1-positive chronic myelogenous leukemia (CML) cell line, KBM5, which lacks the normal chromosome 9 and hence the normal c-Abl product. Because the p210BCR-ABL protein appears cytoplasmic in both chronic phase and blast crisis CML cells, as does the p190BCR-ABL in Ph1-positive acute leukemia, a change in subcellular location of Bcr-Abl proteins between cytoplasm and nucleus cannot explain the different spectrum of leukemias associated with p210 and p190, nor the transition from the chronic to the acute leukemia phenotype seen in CML. Further analysis of fresh CML and normal hematopoietic bone marrow cells reveals that p210BCR-ABL, as well as the normal Bcr and Abl proteins, are expressed primarily in the early stages of myeloid maturation, and that levels of expression are reduced significantly as the cells mature to polymorphonuclear leukocytes. Similarly, a decrease in Bcr and Abl levels occurs in HL-60 cells induced by DMSO to undergo granulocytic differentiation. The action of p210BCR-ABL and its normal counterparts may, therefore, take place during the earlier stages of myeloid development.

Animals↗