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M Talpaz

Publications and source records attributed to M Talpaz.

At least 253 records · Page 14Linked to original sources
PubMed1990

Rearrangement and expression of p53 in the chronic phase and blast crisis of chronic myelogenous leukemia.

We tested a population of over 60 patients with chronic myelogenous leukemia (CML) for changes in the structure and expression of the p53 gene, which is located on chromosome 17. Six of 27 (22%) blast crisis samples and 3 of 5 (60%) accelerated phase samples had rearrangements of chromosome 17, whereas only 3 of 42 (7%) chronic phase patients had cytogenetic changes in chromosome 17. There was no loss of heterozygosity during the transition to blastic crisis among seven individuals who were informative for polymorphic probes for regions in or around the p53 gene on 17p. One patient in the chronic phase and one patient in the blastic phase of the 61 CML patients studied exhibited rearrangements of the p53 gene that were detectable by Southern analysis. One p53 allele was rearranged in the chronic phase patient and both p53 alleles were rearranged in the blastic phase patient. The p53 messenger RNA (mRNA) was of normal size (2.8 kb) in chronic phase and blast crisis, and the expression of the p53 gene was at least as high or higher in blast crisis as in the chronic phase of CML. The high incidence of abnormalities of chromosome 17 in blast-crisis CML found in our studies and the discovery of rearrangements of the p53 gene in two CML patients studied suggest that further study with probes for the p53 gene and anonymous polymorphic sites in chromosome 17 should be conducted in CML.

Blast Crisis↗
PubMed1990

Proposal for a simple synthesis prognostic staging system in chronic myelogenous leukemia.

PURPOSE: Several prognostic models or staging systems have been published that identify different risk groups in patients with Philadelphia chromosome (Ph)-positive chronic myelogenous leukemia (CML). The aims of this study were (1) to test, in an independent population, the prognostic reproducibility of these staging systems; and (2) to develop a synthesis staging system that could be easily applied in clinical practice. PATIENTS AND METHODS: A total of 406 patients with newly diagnosed Ph-positive CML were evaluated by the four published staging systems of Tura, Cervantes, Sokal, and our group. The proposed synthesis staging system was developed based on the most consistent prognostic characteristics, and the presence or absence of accelerated disease features at diagnosis. The staging systems were compared according to survival outcome, as well as by looking for differences of survival outcomes within a specific stage of a defined system, when patients in this stage were subclassified by a second staging system. RESULTS: Whereas the staging system of Cervantes et al identified only two prognostic groups (median survivals of 49 versus 40 months; p = 0.01), the remaining three staging systems were able to segregate patients into stage 1, 2, and 3 risk groups with respective median survivals of 56 to 57, 41 to 42, and 28 to 36 months, respectively (p less than 0.001 to p less than 0.002). The new proposed staging system, based on the existence of zero to one (stage 1), two (stage 2), or three or more unfavorable (stage 3) characteristics, or the presence of accelerated disease features (stage 4), categorized patients into four prognostic groups with median survivals of 56, 45, 30, and 30 months, respectively (p less than 0.001), the latter stage (stage 4) being associated with a higher one-year mortality rate (29%). The synthesis staging system was also able to subclassify patients within most of Tura's and Sokal's stages into significantly different prognostic groups by survival outcome. CONCLUSION: The predictive prognostic capacity of three of the four published staging systems was confirmed in this independent or test population. The new proposed staging system was superior to the staging systems of Tura and Sokal in identifying different prognostic subgroups.

Humans↗
PubMed1990

Alpha interferon dose-dependent suppression of secondary clones in a patient with Philadelphia-positive chronic myelogenous leukemia.

A patient whose chronic myelogenous leukemia (CML) was treated with interferon alpha (IFN-alpha) is described. The disease showed karyotypic evolution during the chronic phase and the later myeloid acceleration. Both of these secondary clonal phenomena responded to IFN-alpha dose escalation. The case illustrates the dose dependence of CML responses to IFN-alpha. The phenomenon of clonal evolution is discussed in the context of this patient's disease.

Clone Cells↗
PubMed1990

A phosphatase activity present in peripheral blood myeloid cells of chronic myelogenous leukemia patients but not normal individuals alters nuclear protein binding to transcriptional enhancers of interferon-inducible genes.

Cytoplasmic protein from peripheral blood myeloid cells of chronic myelogenous leukemia (CML) patients altered the electrophoretic mobility of complexes formed between nuclear proteins and interferon-inducible transcriptional enhancers. Immature myeloid marrow cells (blasts and promyelocytes) have a higher level of this activity than do mature myeloid marrow cells (bands and polys). This activity, which is not detectable in the peripheral blood cells of normal individuals, is at least 50-fold higher in CML marrow blasts and promyelocytes than that found in marrow blasts and promyelocytes of normal individuals. This activity was inhibited by in vivo incubation of immature myeloid cells with the phosphatase inhibitor, sodium orthovanadate (0.2 mM), and by adding orthovanadate (20 mM) directly to cytoplasmic proteins of myeloid cells. Interferon-alpha (1,000 U/ml) reduced the effects of the CML myeloid cell cytoplasmic protein on the electrophoretic mobility of nuclear protein-DNA complexes. These data suggest that a unique phosphatase may be involved in the abnormalities in CML which are modulated by interferon-alpha.

Acid Phosphatase↗
PubMed1990

Update on therapeutic options for chronic myelogenous leukemia.

Chronic myelogenous leukemia (CML) is a myeloproliferative disorder triggered by a chromosomally induced mutation in a pluripotent stem cell. Its progressive clinical course consists of a chronic or benign phase, which terminates in blast crisis. Historically, treatment has been limited: conventional chemotherapy yields a median survival of approximately 36 to 42 months, and bone marrow transplantation, while achieving success in more than half of patients treated, is limited to younger patients with HLA-matched siblings. Treatment with interferon alfa in CML was initiated in 1981. The first studies were performed using partially pure interferon alfa; these studies were followed by treatment regimens employing interferon alfa-2a.

Bone Marrow Transplantation↗
PubMed1990

Effects of granulocyte-macrophage colony-stimulating factor in iatrogenic myelosuppression, bone marrow failure, and regulation of host defense.

In early studies, recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF) has been found to reduce the depth and duration of granulocytopenia in the settings of cancer chemotherapy and autologous bone marrow transplantation. In patients with myelodysplastic syndrome or aplastic anemia. GM-CSF has produced increased marrow cellularity and marked leukocyte responses, and multilineage effects have been observed in some patients. The available data suggest that the use of GM-CSF in these settings is associated with a decreased incidence of infection as compared with that in historical controls or pretreatment periods and that it may enhance the ability to deliver optimal doses of cancer chemotherapy. Other findings suggest that GM-CSF may be useful in regulating host response to infection when used in combination with antimicrobial therapy in neutropenic patients. However, a precise determination of the ability of this agent to significantly affect patient morbidity or mortality in these various contexts awaits the results of larger, longer-term, randomized, controlled trials.

Bone Marrow Diseases↗
PubMed1989

Recombinant interferon-alpha therapy of Philadelphia chromosome-negative myeloproliferative disorders with thrombocytosis.

PURPOSE: The clinical course of patients with myeloproliferative disorders and excessive thrombocytosis may be complicated by serious hemorrhagic or thrombotic events. We have previously reported that interferon-alpha can control severe refractory thrombocytosis in patients with advanced chronic myelogenous leukemia. Therefore, we treated a group of thrombocythemic patients with Ph-negative myeloproliferative disorders, including polycythemia vera and essential thrombocythemia, with recombinant interferon-alpha (rIFN-alpha 2a). PATIENTS AND METHODS: Eight patients with profound elevations in platelet counts received a median induction dose of 5.4 X 10(6) U/day (range, 5.0 to 10.0 X 10(6) U/day) of rIFN-alpha 2a administered intramuscularly or subcutaneously. RESULTS: We observed a significant decline in platelet counts from a median baseline value of 1,929 X 10(9)/L (range, 960 to 2,960 X 10(9)/L) to a median posttreatment value of 431 X 10(9)/L (range, 71 to 1,150 X 10(9)/L) (p less than 0.01). Concomitantly, white blood cell counts declined from a median baseline value of 20.8 X 10(9)/L (range, 10.5 to 40.8 X 10(9)/L) to a median posttreatment value of 6.1 X 10(9)/L (range, 2.9 to 29.0 X 10(9)/L) (p less than 0.02). Correction of thrombocytosis was rapid, with a median of only eight days from the start of therapy to the achievement of a platelet count less than 1,000 X 10(9)/L. Six of eight patients have shown an ongoing response with a median follow-up period of 11 months (range, one to 30 months). There have been no bleeding or thrombotic events during the study. Side effects of rIFN-alpha 2a therapy consisted of fever and flu-like symptoms, with tachyphylaxis developing after one to two weeks of therapy. CONCLUSION: Our observations suggest that alpha interferon may be a promising therapeutic agent for myeloproliferative disorders characterized by thrombocytosis.

Adult↗
PubMed1989

Interleukin-2 alone and in combination with other cytokines in melanoma: the investigational approach at the University of Texas M.D. Anderson Cancer Center.

The clinical data that have been accumulated so far suggests a significant influence of IL-2 dose and schedule on the immunobiological effects and clinical toxicities observed with this cytokine. Consequently, the series of Phase I and Phase II clinical trials conducted at the University of Texas M. D. Anderson Cancer Center in patients with advanced malignant melanoma investigating the use of IL-2 in combination with other cytokines, monoclonal antibodies, or ex vivo activated effector cells have used a common dose and schedule of IL-2 administration for which abundant immunobiological information already exists. This approach allows cross-trial comparison of experience with toxicities, immunobiological observations and clinical activity by a group of investigators within a single institution, and more rapid and valid evolution towards combination biological therapy, which preclinical data suggest will have greater activity than single agent therapy.

Biological Factors↗
PubMed1989

Phase I study of a combination of recombinant tumor necrosis factor-alpha and recombinant interferon-gamma in cancer patients.

Combinations of tumor necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) demonstrate synergistic antiproliferative activity in vitro. Therefore, we initiated a clinical study of recombinant TNF-alpha (rTNF-alpha) and rIFN-gamma combination therapy in humans. Twenty-five patients with metastatic cancer received both rTNF-alpha and rIFN-gamma by intramuscular injection for 5 consecutive days every 2 weeks for a total of 4 weeks. The dose levels were 5/5, 10/5, 10/10, 25/10, 25/25, 50/25, 50/50, 75/50, and 75/75 micrograms/m2 per day of rTNF-alpha/rIFN-gamma. A minimum of 2 patients were entered sequentially at each dose level. If the first 2-week cycle of therapy was well tolerated, the dose was increased to the next highest dose level during the second 2-week cycle. Fever, chills, and fatigue were observed at all doses. Severity of symptoms corresponded to increasing dose levels. Although TNF is identical to a molecule known as "cachectin," the vast majority of our patients did not lose weight while on study. However, alterations in lipid metabolism occurred and were manifested by a median change in triglyceride values of +40 mg/dl (range, -130 to +318 mg/dl), and in cholesterol values of -30 mg/dl (range, -103 to +2 mg/dl). The maximum tolerated dose was 75 micrograms/m2 of rTNF-alpha combined with 50 micrograms/m2 of rIFN-gamma, with dose-limiting side effects being mainly constitutional symptoms. A dose-related suppression in granulocyte and platelet counts was observed. Hematologic parameters returned to baseline within 72 h after therapy was discontinued, and neither infection nor bleeding occurred. Ten of 22 evaluable patients had stable disease for a median of 8 weeks (range, 4-21 weeks); 12 patients showed progressive disease. This study will form the framework for phase II trials of rTNF-alpha and rIFN-gamma combination therapy.

Adolescent↗
PubMed1989

Concomitant administration of recombinant human interleukin-2 and recombinant interferon alpha-2A in cancer patients: a phase I study.

Twenty-seven patients with metastatic cancer were treated with a daily continuous intravenous (IV) infusion of recombinant human interleukin-2 (rhIL-2) along with daily intramuscular recombinant interferon-alpha-2a (rIFN-alpha-2a) 4 days per week for 4 weeks with repeated treatment after 2 to 4 weeks of rest. The maximum-tolerated dose (MTD) was 3 million U/m2/d of rhIL-2 with 5 to 10 million U/m2/d of rIFN-alpha-2a. The dose-limiting toxicities are moderate hypotension requiring low doses of pressors and chronic fatigue associated with decreased performance status. Other common side effects included fever, chills, fluid retention, nausea/vomiting, erythrodermia, weight loss, elevated liver transminase levels, anemia, thrombocytopenia, and CNS toxic effects. There were seven objective responses among 25 evaluable patients. Four major responses (one complete response and three partial responses) were observed among 10 patients with melanoma treated with the MTD level. These data suggest that for cancer patients, concomitant rhIL-2 and rIFN-alpha-2a therapy is tolerable and has manageable side effects. Further phase II studies will be needed to define the antitumor activity of this combination.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

Fludarabine: a new agent with major activity against chronic lymphocytic leukemia.

Fludarabine was used to treat 68 patients with previously treated chronic lymphocytic leukemia (CLL). Nine (13%) patients achieved a complete remission and 30 (44%) a partial remission. The response rates for Rai stages 0 to 2, 3, and 4 were 64%, 58%, and 50% respectively. Seventeen (43%) of the 40 Rai stage 1 to 3 patients and four (19%) of the Rai stage 4 patients returned to Rai stage 0. Survival was strongly correlated with the final Rai stage achieved. The survival of the 11 partial responders with residual disease consisting only of residual bone-marrow nodules was similar to the complete responders (36+ months) and superior to the other partial response patients (16 months). The response to fludarabine was rapid, with 36 (92%) of the 39 responders having achieved at least a partial response following the first three courses. Complete responses occurred in the blood, liver, spleen, and lymph nodes in 48% to 69% of the patients. Eradication of all disease in the bone marrow occurred in only 13% of the cases. Neutropenia and thrombocytopenia occurred in 56% and 25% of evaluable courses. Major infections occurred in 9% of evaluable courses and fevers of unknown origin or minor infections in 12% of courses respectively. Myelosuppression and infection were more common in patients with initial Rai stages 3 and 4 and in nonresponding patients. Other toxicity was mild. No CNS toxicity was noted.

Antimetabolites, Antineoplastic↗
PubMed1989

Cardiac arrhythmia in a CML patient treated with interferons.

We report a case of a 33-year-old woman who developed episodes of palpitation while receiving weekly alternating doses of daily intramuscular recombinant interferon alpha-2a (rIFN alpha-2a) and recombinant interferon gamma (rIFN gamma) for Philadelphia chromosome-positive chronic myelogenous leukemia. The electrocardiogram (ECG) and ambulatory Holter monitoring showed first-degree atrioventricular (A-V) block and episodes of junctional tachycardia. The ECG abnormality and palpitation disappeared after discontinuation of therapy. On rechallenge with recombinant interferon alpha-2b (rIFN alpha-2b) alone, there was recurrent palpitation and first-degree A-V block. Subsequent treatment with various doses of rIFN alpha-2b established a dose-response relationship between rIFN alpha-2b and palpitation in our patient. In view of increasing use of rIFNs in the clinical setting, this potential, albeit uncommon, toxicity requires attention and further investigation.

Adult↗