Biomedical subjects

M Talpaz

Publications and source records attributed to M Talpaz.

At least 307 records · Page 17Linked to original sources

PubMed1987

Molecular analysis of interferon-induced suppression of Philadelphia chromosome in patients with chronic myeloid leukemia.

Treatment with recombinant human interferon alpha-A (Roferon-A) is associated with stable suppression of the population of cells that display the Philadelphia (Ph1) chromosome in some patients with chronic myelogenous leukemia (CML) as defined by cytogenetic analysis. Southern blot analyses employing a 3' breakpoint cluster region (bcr) probe (Pr-1) were performed to confirm a complete suppression of the Ph1+ chromosome-positive clone of cells at the DNA level. The complete disappearance of rearranged restriction fragments of the bcr gene, which were a characteristic of the disease prior to Roferon-A therapy, was accompanied by the restoration of normal bone marrow and achievement of durable ongoing complete remission for 9 and 6 months, respectively, in two patients with Philadelphia-positive (Ph1+) CML. Molecular analysis is a valuable probe for monitoring the clinical course of disease in patients with Ph1+ CML.

Adult↗

PubMed1987

Identification of molecular variants of p210bcr-abl in chronic myelogenous leukemia.

The aberrant abl protein product of a chronic myelogenous leukemia (CML) blast crisis cell line (K562) and of five Philadelphia chromosome-positive CML patients in blast crisis were analyzed by an immune complex kinase assay using two antipeptide sera generated against the hydrophilic domain of v-abl and a region within the third exon of the breakpoint cluster region (bcr) respectively. Both the anti-abl and anti-bcr sera detected a 210 kd band in extracts derived from K562 cells and from two CML patients with myeloid blast crisis. p210 was detected by the anti-abl but not the anti-bcr sera in three CML patients with myeloid (one patient) and lymphoid (two patients) blast crisis, indicating the absence of bcr exon 3 in this protein. Southern blot analysis on DNA derived from one of the patients in the latter group was consistent with the break on chromosome 22 occurring 5' to bcr exon 3. Our observations demonstrate that the Philadelphia translocation results in the generation of a chimeric bcr-abl protein with at least two molecular variants, both of which are enzymatically active as protein kinases.

Blast Crisis↗

PubMed1987

Therapy of chronic myelogenous leukemia with recombinant interferon-gamma.

Recently, we reported that recombinant interferon-alpha (rIFN-alpha) can induce hematologic remissions and cytogenetic improvement in newly diagnosed Philadelphia (Ph)-positive chronic myelogenous leukemia (CML) patients. Although IFN-gamma is a structurally distinct molecule, this agent suppresses in vitro hematopoietic progenitor cells in a fashion similar to that of IFN-alpha. Therefore, we initiated a study of rIFN-gamma at doses of 0.25 to 0.5 mg/m2/d intramuscularly in patients with Ph-positive benign-phase CML. Twenty-six of 30 patients entered in the study were evaluable. Six patients have achieved a complete hematologic response; four, a partial hematologic response. The median follow-up period of patients who are in complete remission is 7.5 months (range, 5 to 12 months). No relapses have occurred among the complete responders. So far, five patients have had cytogenetic improvement with emergence of 5% to 45% diploid cells in the bone marrow. Fever and flulike symptoms were the most common side effects, with partial tolerance often developing after about 1 week. The majority of patients tolerated therapy with minimal change in performance status. In conclusion, rIFN-gamma has demonstrated clinical activity in CML. On the basis of these observations and the in vitro synergistic growth-inhibitory effects of IFN-alpha and IFN-gamma, we have started trials of combination IFN therapy in CML patients.

Adult↗

PubMed1987

Biologic therapy of chronic myelogenous leukemia.

In a study using human IFN-alpha, 36 of 51 patients with chronic phase CML achieved a complete hematologic remission. More significantly, 20 patients showed suppression of Ph-positive metaphases with reappearance of cells with normal karyotype. To date, the authors have treated 44 chronic phase CML patients with recombinant IFN-alpha as their frontline biologic therapy with similar hematologic and cytogenetic responses. Gamma interferon is active against CML but less so than IFN-alpha. Chemotherapy followed by IFN-alpha also shows promise. Interferons have produced only limited responses in terminal phase CML patients.

Blast Crisis↗

PubMed1987

Expression of c-abl in Philadelphia-positive acute myelogenous leukemia.

The identical cytogenetic marker, t(9;22)(q34;q11) (Philadelphia [Ph] translocation), is found in approximately 90%, 20%, and 2% of adult patients with chronic myelogenous leukemia (CML), acute lymphoblastic leukemia (ALL), and acute myelogenous leukemia (AML), respectively. In CML, the molecular events resulting from the Ph translocation include a break within the bcr locus on chromosome 22, transfer of the c-abl protooncogene from chromosome 9 to 22, and formation of an aberrant 210-kD bcr-abl fusion protein (p210bcr-abl). Recently, the absence of bcr rearrangement and expression of a distinct aberrant 190-kd abl protein (p190c-abl) has been described in Ph-positive ALL, with the suggestion that the two abl variants may be pathogenetically associated with myeloid v lymphoid leukemogenesis. Here we report that the genomic configuration and translation product of Ph-positive AML can be similar to that of Ph-positive ALL: the break at 22q11 may occur outside the 5.8 kb bcr region and result in expression of a 190-kD abl protein lacking these bcr sequences. Phosphokinase enzymatic activity, a fundamental property of p210bcr-abl, was also associated with AML-derived p190c-abl. Our current observations indicate that p190c-abl can be found in cells of lymphoid or myeloid lineage and is therefore unlikely to play a specific role in the development of lymphoid leukemias. Formation of p190c-abl instead of p210bcr-abl appears to be a characteristic of the acute rather than the chronic Ph-positive leukemic state.

Cell Line↗

PubMed1987

Clinical investigation of human alpha interferon in chronic myelogenous leukemia.

Fifty-one patients with previously untreated or minimally treated chronic myelogenous leukemia in chronic phase received human alpha interferon 3 to 9 X 10(6) units intramuscularly (IM) daily until complete hematologic remission, then at doses ranging from 3 X 10(6) units every other day to 9 X 10(6) units daily. Forty-one (80%) patients achieved a hematologic response, 36 (71%) of them attaining a complete hematologic remission with normal peripheral WBC and differential counts. Responding patients showed continuous but slow normalization of several other blood and marrow parameters including platelet counts, serum lactic dehydrogenase and B12 levels, and marrow cellularity and maturation index. Suppression of the Philadelphia chromosome on serial cytogenetic studies of marrow metaphases was documented in 20 of the 36 patients who achieved complete hematologic remission (56%; 39% of total group), eight of whom (22%) had a decrease of the Philadelphia chromosome-positive metaphases to less than 35%. These changes were persistent for 6 months or longer in 18 patients, seven of whom had continuous suppression of the Philadelphia chromosome to less than 90% for a median of 30+ months (range 21+ to 39+ months). After a median follow-up period of 37 months, 25 patients remain in continued disease control with interferon therapy. The projected 3-year survival rate is 76%, with a yearly death rate of 6%, 9%, and 9% in the first 3 years. Response, Philadelphia chromosome suppression, and survival were significantly better among patients in the low-risk category compared to intermediate- and high-risk categories, as defined by a multivariate analysis-derived prognostic model. The projected 3-year survival rate was 94% for patients who achieved a complete hematologic remission on interferon therapy and 45% for those who did not. Thirteen patients have developed blastic crisis, six with lymphoid and three with undifferentiated morphology. We conclude that human leukocyte alpha interferon effectively controls chronic myeloid leukemia and allows reappearance of diploid hemopoietic cells in some patients.

Aged↗

PubMed1987

Old age: a sign of poor prognosis in patients with chronic myelogenous leukemia.

Fifty-four patients aged 60 years or older with a diagnosis of chronic myelogenous leukemia were referred to University of Texas M. D. Anderson Hospital between 1965 and 1982. Patients in this age group had a significantly shorter median survival than that of the 249 patients younger than 60 seen during the same period (26 vs 42 months; P = .01). Old age was associated with a higher incidence of poor performance status, hepatomegaly, and anemia. Fourteen other patient characteristics were correlated with poor prognosis, including black race, weight loss, symptoms, hepatomegaly, splenomegaly, anemia, thrombocytopenia or thrombocytosis, increased peripheral blast cells and promyelocytes or basophils, increased blasts or basophils in the bone marrow, decreased megakaryocytes, and additional cytogenetic abnormalities. A multivariate analysis that accounted for the interactions of these factors identified old age as being of primary adverse prognostic significance in patients with chronic myelogenous leukemia, suggesting a biologic difference in the disease in older patients. The poor prognosis in elderly patients receiving present available therapy justifies promising and well tolerated investigational approaches such as interferons in patients in this age group.

Age Factors↗

PubMed1987

The effect of long-term marrow culture on the nonadherent Philadelphia chromosome-positive clone in chronic myelogenous leukemia: preliminary observations.

To evaluate the effect of long-term culture on the Philadelphia chromosome-positive nonadherent hemopoietic clone in chronic myelogenous leukemia, bone marrow aspirates from five patients were grown in culture for three to four weeks. In addition to control cultures, samples were incubated with recombinant alpha-interferon. Cytogenetic studies performed on the nonadherent hemopoietic cells demonstrated suppression of the Philadelphia chromosome-positive clones, and appearance of cells with normal diploid karyotype in two of the five patients studied; cells from the remaining three patients showed persistent Philadelphia chromosome-positive cells in 100% of the metaphases. Exposure to alpha-interferon did not enhance the suppression of the Philadelphia chromosome-positive clones. A good correlation was noted between in vitro results and in vivo cytogenetic response: the two patients whose in vitro studies showed diploid clones achieved complete hematologic remission and suppression of Philadelphia chromosome-positive metaphases with therapy. Our data suggest that long-term culture favors the growth of normal clones over Philadelphia chromosome-positive clones in the nonadherent hemopoietic cells of some patients with chronic myelogenous leukemia. The value of the procedure as an in vitro predictive test for residual normal stem cells and response to therapy and for autologous marrow in vitro purging needs further exploration.

Adult↗

PubMed1987

Prognosis of chronic lymphocytic leukemia: a multivariate regression analysis of 325 untreated patients.

Three hundred twenty-five previously untreated patients with chronic lymphocytic leukemia were analyzed to identify significant prognostic factors for survival. Univariate analysis identified the following characteristics associated with survival: (1) clinical characteristics: age, race, sex, performance status, lymphadenopathy, and hepatosplenomegaly; (2) hematologic parameters: WBC count, absolute lymphocyte and granulocyte counts, hemoglobin level, and platelet count; and (3) biochemical parameters: serum albumin, calcium, uric acid, lactate dehydrogenase, alkaline phosphatase, BUN, and creatinine. Multivariate regression analysis in a randomly selected training subset of 217 patients demonstrated that the combination of uric acid, alkaline phosphatase, lactate dehydrogenase, external lymphadenopathy, and age had the strongest predictive relation to survival time. The resulting model was validated in the remaining independent subset of 108 patients and led to classification of patients into low, intermediate, and high-risk groups with five-year survival rates of 75%, 59%, and 14%, respectively, and with distinctively different annual mortality rates (P less than .01). Both the regression model and Rai staging were highly effective in identifying risk groups among the entire patient population (P less than 0.001). Overall the regression model was superior to Rai staging in defining prognostic risk groups. In addition, it was able to separate patients into significantly different risk categories within each Rai stage, thus improving on the prognostic prediction of individual patients with chronic lymphocytic leukemia.

Adult↗

PubMed1986

Clinical and prognostic features of Philadelphia chromosome-negative chronic myelogenous leukemia.

Between 1965 and 1982, 105 patients with a diagnosis of Philadelphia chromosome-negative chronic myelogenous leukemia were referred to our institution with minimal or no prior therapy. The median age was 63 years and 64% were males. The overall median survival from time of referral was 14 months; 53% of patients survived 1 year and only 10% survived beyond 5 years. At the time of analysis, 92 patients (88%) were dead, 56% of deaths being preceded by a blastic crisis. Compared with Philadelphia chromosome-positive disease, patients with Philadelphia chromosome-negative chronic myelogenous leukemia were older and had a significantly higher incidence of anemia, thrombocytopenia, monocytosis, marrow blasts, decreased marrow megakaryocytes and a lower incidence of basophilia and thrombocytosis. Chromosomal abnormalities occurred in 33% of patients and consisted most frequently of trisomy 8, or an additional chromosome C, loss of the Y chromosome, or abnormalities in chromosomes #5 and #7. Of nine pretreatment characteristics significantly associated with poor survival, a multivariate analysis identified four to have independent additive prognostic significance: severe thrombocytopenia, hemoglobin levels less than 10 g/dl, increasing peripheral blasts and promyelocytes, and age 60 years or older. Monocytosis was not of prognostic significance. The derived prognostic model divided patients into three risk groups, low, intermediate, and high, with median survivals of 36, 16, and 3 months, respectively. The authors conclude that Philadelphia chromosome-negative chronic myelogenous leukemia is a distinct entity among the myeloproliferative syndromes with characteristic clinical and laboratory features and a poor prognosis. Prognostic factors and related risk categories were demonstrated within this disease entity.

Adolescent↗

PubMed1986

Hematologic remission and cytogenetic improvement induced by recombinant human interferon alpha A in chronic myelogenous leukemia.

We treated 17 patients who had Philadelphia-chromosome-positive chronic myelogenous leukemia (4 of whom had not received therapy and 13 of whom had been treated with hydroxyurea or busulfan for less than six months) with recombinant human interferon alpha A (Roferon-A). The interferon was given as 5 X 10(6) units per square meter of body-surface area per day intramuscularly during induction therapy. Fourteen patients responded to the treatment, of whom 13 had a hematologic remission and 1 had a partial hematologic remission. The median number of white cells in those patients declined from 60.9 X 10(3) to 3.4 X 10(3) per microliter, and the median number of platelets decreased from 476 X 10(3) to 231 X 10(3) per microliter. Among the five responding patients who had splenomegaly before treatment, the spleen size returned to normal in four and decreased by 75 percent in one, although it remained enlarged. Bone marrow cellularity declined from a median of 92.5 percent to a median of 57.5 percent. In six of the patients with hematologic remission, complete suppression of Philadelphia cells was observed on at least one examination. Of the 14 patients who responded, 11 have received the interferon therapy for 9 to 15 months. One patient relapsed during the treatment, and the treatment has been temporarily interrupted in two patients because of toxicity. These data are preliminary and will need further confirmation, but they suggest that recombinant human interferon alpha A is effective in inducing hematologic remission in most patients with benign-phase chronic myelogenous leukemia and in suppressing the Philadelphia chromosome in some of these patients.

Adolescent↗

PubMed1986

Difluoromethylornithine and leukocyte interferon: a phase I study in cancer patients.

Difluoromethylornithine (DFMO), an irreversible inhibitor of ornithine decarboxylase, and human leukocyte interferon (IFN-alpha) have synergistic anti-tumor activities in vivo in B 16 melanoma and in vitro against several human cancer cell lines. We have, therefore, carried out a phase I combination study with DFMO plus alpha interferon in the following manner: DFMO was maintained at a steady dose for the first four levels, 1.5 g/m2 every 6 hr. IFN-alpha was given in 100% increments ranging from 0.4 X 10(6)U/m2 to 3.2 X 10(6)U/m2 i.m. daily. At the fifth dose level both IFN-alpha and DFMO were raised by 100 and 50% respectively. From levels one through four the combination was well tolerated with no dose interruptions required because of G.I. toxicity or myelosuppression. However, at dose level 5, one-third of the patients required dose cessation and decrease due to nausea, vomiting and diarrhea. We conclude that for phase II studies the maximal tolerated dose is 3.2 million units of IFN-alpha/m2 and 1.5 g/m2 of DFMO every 6 hr. Of 12 patients with metastatic melanoma, 2 had partial remissions lasting 58+ and 36+ weeks. Two additional patients had minor responses lasting 29 and 32+ weeks. Minor responses were observed in a patient with colon carcinoma and a patient with renal carcinoma. The clinical activity of the combination is currently being pursued in a phase II study among patients with metastatic malignant melanoma.

Adult↗

PubMed1986

Altered expression of G1-specific genes in human malignant myeloid cells.

We have studied the expression of cell-cycle genes specific to the G1 (2A9, 2F1, 4F1, c-myc) and S (histone H3) phases of the cell cycle in normal and malignant human myeloid cycling cells. The levels of expression were determined by measuring the amounts of specific RNA in blot hybridization assays. Levels of expression of the G1 genes were compared to the level of expression of the S-phase-specific H3 gene. This method can distinguish whether an increased expression of G1 genes is truly due to deregulation or simply reflects an increase in the fraction of proliferating cells. In a normal asynchronous system provided by the bone marrow cells of three normal donors, the expressions of the four G1-specific genes 2A9, 2F1, 4F1, and c-myc, and of the S-phase-specific gene H3 were in ratios that differed little from one individual to another. In the total RNA of eight patients in the chronic phase of chronic myelogenous leukemia, a high level of expression of G1 cell-cycle genes was paralleled by a high level of expression of the S-phase H3 gene, simply reflecting an increase in the fraction of proliferating cells. In patients with acute myelogenous leukemia (AML), the RNA levels of 2F1 and 4F1 paralleled the expression of H3-i.e., the ratios of expression 2F1/H3 and 4F1/H3 were the same as in normal bone marrow cells. However, in 9 of 10 patients with AML we found that the expression of c-myc was elevated with respect to H3 expression. The expression of 2A9 (with respect to H3) was also elevated in some of these AML patients. Two important conclusions can be drawn from these findings: increased levels of a G1-specific RNA in a tumor may not indicate overexpression of that gene but may instead simply reflect the fraction of proliferating cells; and in some patients with AML, however, the expression of certain G1 genes is truly deregulated and might contribute to the impairment of proliferative control that is associated with this phenotype.

Cell Cycle↗

PubMed1986

Chronic myelogenous leukaemia: haematological remissions with alpha interferon.

Twenty-seven consecutive patients with previously untreated, or minimally treated benign phase Philadelphia-chromosome-positive, chronic myelogenous leukaemia (CML) were treated with partially purified human leucocyte (alpha) interferon; 24 of the 27 patients responded to therapy achieving either haematological remission (20 patients) or partial haematological remission (four patients). In the responding patients the peripheral white blood cells declined from a median of 89.6 X 10 X 10(9)/l to 4.5 X 10 X 10(9)/l. The serum lactate dehydrogenase declined from a mean of 8.36 Katal/l (492 mu/ml) to 2.8 Katal/l (165 mu/ml), and the vitamin B12 levels declined from 1492 pg/ml to 838 pg/ml. Fifteen patients had splenomegaly. The spleen size normalized in four and decreased by a median of 30% in 10 additional patients. The bone marrow cellularity fell from a median of 100% to a median of 62%. In seven of the 24 responding patients, followed for greater than or equal to 6 months, the percentage of Ph1-positive cells in the bone marrow declined to a median of 70% (range 5-75%). Alpha interferon was found to be an effective therapeutic agent for controlling the myeloid proliferation in CML, and in partially restoring the nonclonal haematopoietic cells in some of the patients.

Adult↗

PubMed1986

Clinical toxicity of interferons in cancer patients: a review.

All major types of human interferons (IFNs) have been purified and clinically administered as antitumor agents. We summarize here experience to date with toxicity of IFNs in cancer patients. The acute syndrome consists of fever, chills, myalgias, arthralgias, and headache, with some variation according to type of IFN, route of administration, schedule, and dose. Fatigue, perhaps reflecting CNS toxicity, is the most prevalent nonacute symptom. At high doses, IFNs are neurotoxic; the abnormalities seen by EEG resemble those in diffuse encephalitis. Hematologic toxicity consists mainly of leukopenia, but anemia and thrombocytopenia occur in some patients. Nausea, vomiting, and diarrhea are the main gastrointestinal symptoms. Elevation of serum transaminases seems to reflect liver toxicity. Renal function is well preserved, except for rare instances of acute renal failure. Cardiac toxicity remains questionable, although heart failure and arrhythmias have been associated with the administration of IFNs. Most, if not all, of these effects are reversible or can be ameliorated. With IFN alpha, the type most widely used in clinical studies, doses of 1 million to 9 million units (MU) are generally well tolerated, but doses greater than or equal to 18 MU yield moderate to severe toxicity. Doses greater than or equal to 36 MU can induce severe toxicity and significantly alter the performance status of the patient.

Antibody Formation↗

PubMed1986

Phase I study of multiple dose intramuscularly administered recombinant gamma interferon.

We report the results of a phase I study of the tolerance and biologic activity of intramuscularly (IM)-administered recombinant interferon-gamma (rIFN-gamma). Forty-four patients with metastatic cancer were given rIFN-gamma at doses ranging from 0.01 to 2.5 mg/m2/d for 42 days. The most common side effects were fever, flulike symptoms, night sweats, and granulocytopenia. The maximum tolerated dose was 0.5 mg/m2/d. Administration of rIFN-gamma resulted in modulation of immune system functions, including induction of major histocompatibility complex-associated antigens on blood leukocytes, an increase in blood surface immunoglobulin-bearing B cell and natural killer (NK) cell number, and NK cell cytotoxicity. Serum lysozyme, determined as an estimate of tissue macrophage activity, also increased. Serum assays for anti-interferon antibodies were negative in all patients. Five of eight evaluable patients with lymphoproliferative disorders showed objective evidence of tumor regression consisting of partial responses (two patients), and minor responses (three patients). These data suggest that further phase II studies of IM-administered rIFN-gamma are indicated.

Agranulocytosis↗

PubMed1986

Rearrangement in the breakpoint cluster region and the clinical course in Philadelphia-negative chronic myelogenous leukemia.

We have followed one patient with Philadelphia (Ph)-negative chronic myelogenous leukemia and identified an additional four patients from the literature who showed the rearrangement in the breakpoint cluster region (bcr) on chromosome 22 characteristic of Ph-positive chronic myelogenous leukemia. The clinical course of these five patients was similar to that of Ph-positive patients, with easily controlled leukocyte counts, a prolonged benign phase, and prolonged survival. Furthermore, we have shown, for the first time, that bcr rearrangement in Ph-negative chronic myelogenous leukemia can result in expression of the aberrant 210-kilodalton bcr-abl fusion protein, which has been strongly implicated in Ph-positive leukemogenesis. Research data pertaining to possible cytogenetic mechanisms leading to production of p210bcr-abl in the absence of the Ph chromosome are reviewed. Molecular analysis provides an important tool for classifying and predicting prognosis of some patients with Ph-negative chronic myelogenous leukemia.

Chromosomes, Human, Pair 11↗

PubMed1986

In vivo sensitivity and resistance of chronic myelogenous leukemia cells to alpha-interferon: correlation with receptor binding and induction of 2',5'-oligoadenylate synthetase.

Fourteen patients with chronic myelogenous leukemia were treated with partially pure leukocyte interferon (HuIFN alpha). The binding of recombinant leukocyte clone A IFN and the induction of 2',5'-oligoadenylate synthetase (2,5A) in peripheral blood cells were studied to determine whether they correlate with clinical response to IFN therapy. The mean pretherapy binding of radiolabeled recombinant leukocyte clone A IFN to peripheral blood cells was 0.053 +/- 0.02 (SE) fmol (53 +/- 20 amol)/10(6) cells and 0.049 +/- 0.015 fmol/10(6) cells in sensitive and resistant patients, respectively. Twenty-four h after the first HuIFN alpha dose, the binding of recombinant leukocyte clone A IFN decreased 3- to 8-fold in both sensitive and resistant patients. The activity of 2,5A synthetase was induced approximately 100-fold in sensitive patients from a pretherapy mean of 3 +/- 2 nmol/mg to a maximum of 317 +/- 184 nmol/mg during therapy. In contrast, 2,5A synthetase was induced from a pretherapy mean of 0.9 +/- 0.9 nmol/mg to only 6.7 +/- 4.9 nmol/mg in resistant patients. In two patients originally sensitive to HuIFN alpha who developed resistance to therapy, receptors were present in both sensitive and resistant disease stages and appeared to down regulate with therapy regardless of response. In these two patients, 2,5A synthetase was significantly induced with therapy in the sensitive stage but not in the resistant stage. This study shows that lack of clinical response to interferon therapy may coincide with failure to induce 2,5A synthetase activity. This suggests that resistance to alpha-interferon therapy may be mediated by events beyond receptor binding resulting in a failure to induce enzymes responsible for mediation of interferon antiproliferative effects.

2',5'-Oligoadenylate Synthetase↗