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Biomedical subjects

S R Frankel

Publications and source records attributed to S R Frankel.

At least 37 records · Page 2Linked to original sources
PubMed1994

Treatment of acute promyelocytic leukemia with all-trans retinoic acid: an update of the New York experience.

In an ongoing study, we treated 79 patients with a molecular diagnosis of acute promyelocytic leukemia (APL) using all-trans retinoic acid (RA) for remission induction. Newly diagnosed patients received cytotoxic chemotherapy for consolidation, and previously treated patients received extended all-trans RA therapy, or a radionuclide-conjugated monoclonal antibody as post-remission treatment. Unlike studies in Europe, full-dose chemotherapy was not given during induction for patients who developed leukocytosis. Overall, 43 of 49 newly diagnosed patients (88%) and 25 of 30 previously treated patients (83%) achieved complete remission. We did not encounter de novo resistance to all-trans RA in any patient who was positive for PML/RAR-alpha rearrangements by reverse transcription polymerase chain reaction analysis. Ten patients died during induction from intracranial or pulmonary hemorrhage (six patients) or the 'retinoic acid syndrome' (four patients). The use of leukapheresis or low-dose chemotherapy (hydroxyurea or cytosine arabinoside) for drug-induced leukocytosis did not decrease early mortality. Compared to historical controls, early mortality was not affected by treatment with all-trans RA; however, both relapse-free and overall survival were significantly increased. Maintenance therapy with all-trans RA was associated with short remission duration, and relapses while taking the drug were universally associated with resistance to further retinoid treatment. We conclude that the use of all-trans RA for remission induction, with or without full-dose chemotherapy, has significantly increased the survival of patients with APL. While early mortality has not yet been reduced, the avoidance of full-dose chemotherapy during induction has significantly reduced early morbidity. The major outstanding clinical issue is the development of strategies that maximize safety in high-risk patients for whom intracranial hemorrhage remains the major cause of death.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Treatment of acute promyelocytic leukemia with all-trans retinoic acid: an update of the New York experience.

In an ongoing study, we treated 79 patients with a molecular diagnosis of acute promyelocytic leukemia (APL) using all-trans retinoic acid (RA) for remission induction. Newly diagnosed patients received cytotoxic chemotherapy for consolidation, and previously treated patients received extended all-trans RA therapy, or a radionuclide-conjugated monoclonal antibody as post-remission treatment. Unlike studies in Europe, full-dose chemotherapy was not given during induction for patients who developed leukocytosis. Overall, 43 of 49 newly diagnosed patients (88%) and 25 of 30 previously treated patients (83%) achieved complete remission. We did not encounter de novo resistance to all-trans RA in any patient who was positive for PML/RAR-alpha rearrangements by reverse transcription polymerase chain reaction analysis. Ten patients died during induction from intracranial or pulmonary hemorrhage (six patients) or the 'retinoic acid syndrome' (four patients). The use of leukapheresis or low-dose chemotherapy (hydroxyurea or cytosine arabinoside) for drug-induced leukocytosis did not decrease early mortality. Compared to historical controls, early mortality was not affected by treatment with all-trans RA; however, both relapse-free and overall survival were significantly increased. Maintenance therapy with all-trans RA was associated with short remission duration, and relapses while taking the drug were universally associated with resistance to further retinoid treatment. We conclude that the use of all-trans RA for remission induction, with or without full-dose chemotherapy, has significantly increased the survival of patients with APL. While early mortality has not yet been reduced, the avoidance of full-dose chemotherapy during induction has significantly reduced early morbidity. The major outstanding clinical issue is the development of strategies that maximize safety in high-risk patients for whom intracranial hemorrhage remains the major cause of death.

Antigens, Surface↗
PubMed1993

Detection of minimal residual disease in acute promyelocytic leukemia by a reverse transcription polymerase chain reaction assay for the PML/RAR-alpha fusion mRNA.

The characteristic reciprocal translocation t(15;17) of acute promyelocytic leukemia (APL) disrupts the PML gene on chromosome 15 and the retinoic acid receptor-alpha (RAR-alpha) gene on chromosome 17. PML/RAR-alpha fusion mRNAs are then transcribed and can be detected by a newly described reverse transcription polymerase chain reaction (RT-PCR) assay. Using RT followed by nested PCR amplification for PML/RAR-alpha, we serially evaluated bone marrow aspirates from patients with APL who were treated with all-trans retinoic acid (RA) for induction, followed by all-trans RA as maintenance or cytotoxic drugs as consolidation. At diagnosis, PML/RAR-alpha mRNA was detected in all patients. After initial therapy with all-trans RA, the RT-PCR assay remained positive after induction of complete remission in 31 of 32 evaluable patients. Maintenance treatment by all-trans RA alone was associated with persistent assay positivity and subsequent clinical relapse in 13 of 13 patients. By contrast, the test became negative in 19 of 20 newly diagnosed patients who received consolidation chemotherapy; the 1 patient who remained positive relapsed at 12 months. Three of the 19 assay-negative patients later converted to positive and subsequently relapsed; the remaining 16 patients have remained RT-PCR negative in sustained first remission, with a median follow-up duration that exceeds 24 months (range, 12+ to 34+ months). Despite induction of complete remission in a high proportion of patients, all-trans RA rarely eradicates molecular evidence of disease in patients with APL; however, subsequent treatment with cytotoxic chemotherapy frequently converts the RT-PCR assay for PML/RAR-alpha to negative. Serial negative tests are associated with prolonged disease-free survival, whereas persistence of a positive test after treatment is highly correlated with subsequent relapse. This test identifies patients in remission at high risk for relapse who may benefit from additional antileukemic therapy.

Antineoplastic Agents↗
PubMed1993

High-dose cytarabine, idarubicin, and granulocyte colony-stimulating factor remission induction therapy for previously untreated de novo and secondary adult acute myeloid leukemia.

This report describes the preliminary results of the remission induction phase of a protocol for previously untreated de novo and secondary acute myeloid leukemia (AML) designed to deliver very intensive therapy over a brief period of time using hematopoietic growth factor support. Remission induction therapy consisted of cytarabine 3 g/m2 (1.5 g/m2 for age > 50 years) intravenously over 1 hour every 12 hours for 12 doses and idarubicin 12 mg/m2 over 30 minutes on days 2, 3, and 4 of cytarabine, followed by 10 micrograms/kg granulocyte colony-stimulating factor subcutaneously daily until the absolute neutrophil count increased to > or = 5.0 x 10(9)/L on 2 consecutive days. Twenty-seven patients received all the planned doses of chemotherapy. The complete remission (CR) rate to a single course of therapy was 65% in 20 patients with de novo AML (median age, 60.5 years; age range, 26 to 78 years); for those aged less than 60 and > or = 60 years, the CR rates were 90% and 40%, respectively. In contrast, only two of 10 patients with secondary AML (median age, 68 years; age range, 35 to 77 years) achieved a CR. The median time from initiation of chemotherapy to recovery of 0.5 x 10(9)/L neutrophils in de novo AML patients achieving CR was 20 days (range, 18 to 23 days). Median times to last platelet transfusion and to 100 x 10(9)/L platelet count were 23 days (range, 18 to 41 days) and 28 days (range, 24 to 97 days), respectively. The major nonhematologic toxicity was transient hyperbilirubinemia, which was observed in 64% of patients. Reversible cerebellar toxicity was seen in three patients. Thus, idarubicin at full dose (12 mg/m2 x 3 days) may be safely administered with high-dose cytarabine, even in elderly patients. The use of granulocyte colony-stimulating factor is associated with rapid neutrophil recovery without obvious toxicity. The CR rate for de novo AML patients treated with a single course of high-dose cytarabine, idarubicin, and granulocyte colony-stimulating factor is at least comparable to CR rates achieved with standard-dose cytarabine and anthracycline regimens. The response of secondary AML patients remains inferior.

Acute Disease↗
PubMed1993

Acute promyelocytic leukemia. New insights into diagnosis and therapy.

The clinical and laboratory features of APL are distinct. APL has been effectively treated with anthracyclines. Postremission therapy and the addition of other cytotoxic agents in induction may be beneficial. Early deaths remain a problem despite improved management of coagulopathy. The cytogenetic marker, t(15;17), reflects a molecular defect that splices two transcription factors, PML and RARA, to produce chimeric mRNA and proteins. RA, the natural ligand for RARA, is able to induce CR by stimulating differentiation and maturation of the malignant cells. The addition of RA to the therapeutic armamentarium of the hematologic oncologist will allow further refinement of the management of these patients. Diagnosis is unambiguous because the molecular defect can be readily detected. Our understanding of the biology downstream of the affected genes is incomplete. Other retinoids may be more effective than all-trans RA and may avoid the fall in plasma levels seen in patients chronically treated with RA. Combination of retinoids with other cytokines or cytotoxic agents may decrease the immediate mortality and improve long-term DFS in APL.

Antibiotics, Antineoplastic↗
PubMed1992

Endogenous peptides of a soluble major histocompatibility complex class I molecule, H-2Lds: sequence motif, quantitative binding, and molecular modeling of the complex.

To gain insight into the rules that govern the binding of endogenous and viral peptides to a given major histocompatibility complex (MHC) class I molecule, we characterized the amino acid sequences of a set of self peptides bound by a soluble analogue of murine H-2Ld, H-2Lds. We tested corresponding synthetic peptides quantitatively for binding in several different assays, and built three-dimensional computer models of eight peptide/H-2Lds complexes, based on the crystallographic structure of the human HLA-B27/peptide complex. Comparison of primary and tertiary structures of bound self and antigenic peptides revealed that residues 2 and 9 were not only restricted in sequence and tolerant of conservative substitutions, but were spatially constrained in the three-dimensional models. The degree of sequence variability of specific residues in MHC-restricted peptides reflected the lack of structural constraint on those amino acids. Thus, amino acid residues that define a peptide motif represent side chains required or preferred for a close fit with the MHC class I heavy chain.

Amino Acid Sequence↗
PubMed1992

The "retinoic acid syndrome" in acute promyelocytic leukemia.

OBJECTIVE: To describe a novel complication of therapy with all-trans retinoic acid in patients with acute promyelocytic leukemia. DESIGN: Case series. SETTING: Comprehensive cancer center. PATIENTS: Consecutive patients with a morphologic diagnosis of acute promyelocytic leukemia who underwent remission induction treatment with all-trans retinoic acid, 45 mg/m2 body surface area per day. MEASUREMENTS AND RESULTS: Nine of 35 patients (26%; 95% CI, 9% to 52%) with acute promyelocytic leukemia who were treated with all-trans retinoic acid developed a syndrome consisting primarily of fever and respiratory distress. Additional prominent signs and symptoms included weight gain, lower-extremity edema, pleural or pericardial effusions, and episodic hypotension. The onset of this symptom complex occurred from 2 to 21 days after starting treatment. Three deaths occurred; post-mortem examinations in two patients showed pulmonary interstitial infiltration with maturing myeloid cells. Six other patients survived, each achieving complete remission (five patients with all-trans retinoic acid only; 1 patient with chemotherapy). In six of the nine cases, the onset of the syndrome was preceded by an increase in peripheral blood leukocytes to a level of at least 20 x 10(9) cells/L. Certain therapeutic interventions, including leukapheresis, temporary cessation of therapy with all-trans retinoic acid, and cytotoxic chemotherapy in moderate doses were not useful after respiratory distress was established. However, the administration of high-dose corticosteroid therapy (dexamethasone, 10 mg IV intravenously every 12 hours for 3 or more days) early in the course of the syndrome resulted in prompt symptomatic improvement and full recovery in three of four patients. CONCLUSIONS: The use of all-trans retinoic acid to induce hematologic remission in patients with acute promyelocytic leukemia is associated in some patients with the development of a potentially lethal syndrome that is not uniformly accompanied by peripheral blood leukocytosis. Early recognition of the symptom complex of fever and dyspnea, combined with prompt corticosteroid treatment, may decrease morbidity and mortality associated with this syndrome.

Adult↗
PubMed1992

Clinical pharmacology of oral all-trans retinoic acid in patients with acute promyelocytic leukemia.

All-trans retinoic acid (RA) induces leukemic cell differentiation and complete remission in a high proportion of patients with acute promyelocytic leukemia (APL). However, remissions induced by all-trans RA tend to be brief, and relapses are associated with resistance to further treatment in vivo, although the leukemic cells appear to retain sensitivity to the cytodifferentiating effects of all-trans RA in vitro. The clinical pharmacology of all-trans RA was examined in 13 patients with APL. The drug was administered at a constant dose of 45 mg/m2/day, given as a single dose on the first day of therapy and in two divided doses thereafter. Plasma and urinary concentrations of the parent drug and metabolites were quantitated by reverse-phase high-performance liquid chromatography and, where required, by a combination of normal-phase liquid chromatography/negative chemical ionization mass spectrometry. In patients with APL, basal levels of endogenous retinol and natural retinoids were within the normal range. Peak plasma levels of all-trans RA (347 +/- 266 ng/ml, mean +/- SD) were reached 1-2 h after drug ingestion and decayed in a monoexponential fashion with a half-life of 0.8 +/- 0.1 h. The only drug metabolite detected in plasma or urine was 4-oxo-all-trans RA (present in urine as the glucuronide conjugate). This metabolite accounted for less than 10% of the circulating drug in plasma, and its cumulative urinary excretion accounted for less than 1% of the administered dose. The drug was not found in cerebrospinal fluid. Continued oral administration of all-trans RA was associated with a significant decrease in both the plasma peak levels and the area under the concentration-time curve (P = 0.01 and 0.004, respectively) when measured after 2-6 weeks of treatment. We previously reported that a decrease in plasma area under the concentration-time curve was highly correlated with clinical relapse. Observations in a subset of patients in this study suggested that, in fact, the major decrease occurred early, within the first 7 days of treatment. These changes were associated with a 10-fold increase in urinary excretion of 4-oxo-all-trans RA glucuronide, suggesting that the accelerated clearance from plasma was associated with increased drug catabolism. The rapid disappearance may explain early relapse from remissions induced by all-trans RA; clinical "resistance" to all-trans RA may either wholly or in part result from an inability to sustain effective plasma concentrations of all-trans RA during continuous treatment.(ABSTRACT TRUNCATED AT 400 WORDS)

Administration, Oral↗
PubMed1992

Reverse transcription polymerase chain reaction for the rearranged retinoic acid receptor alpha clarifies diagnosis and detects minimal residual disease in acute promyelocytic leukemia.

The characteristic t(15;17) of acute promyelocytic leukemia (APL) fuses the retinoic acid receptor alpha (RAR-alpha) gene on chromosome 17 to a gene on chromosome 15 called PML, a putative transcription factor. This distinct translocation results in a fusion mRNA detected by Northern analysis. Two cDNAs have been isolated that differ in the extent of 3' PML nucleic acid sequence contained. This study describes a reverse transcription polymerase chain reaction (RT-PCR) assay for the PML/RAR-alpha fusion transcript, which amplifies PML/RAR-alpha mRNA from APL cells with either reported breakpoint. DNA sequencing of the predominant RT-PCR products from 6 patients showed identical RAR-alpha exonic breakpoints and two PML breakpoints. This RT-PCR assay was positive in leukemic cells from 30/30 APL patients with the molecular rearrangement confirmed by cytogenetics or Northern analysis. In leukemic cells of patients with a morphologic diagnosis of APL lacking the t(15;17) by routine cytogenetics, a positive RT-PCR assay predicted clinical response to all-trans-retinoic acid (RA) therapy. Dilutional studies with leukemic cells that express (NB4) or do not express (HL-60) a PML/RAR-alpha fusion mRNA reveal that this RT-PCR assay detects the transcript from as little as 50 pg of total RNA. In APL cells from 5/6 patients treated with RA alone, a complete response by clinical and cytogenetic criteria accompanied a persistently positive RT-PCR assay. This preceded relapse by 1-6 months. RT-PCR for PML/RAR-alpha mRNA provides a more-sensitive test for the t(15;17) than routine cytogenetics or Northern analysis. This molecular rearrangement detected by RT-PCR best defines this RA-responsive malignancy. The RT-PCR assay for the PML/RAR-alpha transcript yields important diagnostic and prognostic information in the management of APL patients.

Base Sequence↗
PubMed1992

Continuous treatment with all-trans retinoic acid causes a progressive reduction in plasma drug concentrations: implications for relapse and retinoid "resistance" in patients with acute promyelocytic leukemia.

Although all-trans retinoic acid (RA) induces complete remission in a high proportion of patients with acute promyelocytic leukemia (APL), all groups have described clinical relapses despite continued RA treatment. This finding suggests that resistance to the cytodifferentiating effects of the retinoid had been acquired. To investigate potential mechanisms of clinical resistance to RA, we serially evaluated the clinical pharmacology of the drug in APL patients treated with this agent. Leukemic cells from patients relapsing from RA treatment were cultured in the presence of RA and examined for evidence of morphologic maturation. We also studied messenger RNA expression of the newly described gene product of the (15;17) translocation in APL, PML/RA receptor-alpha (PML/RAR-alpha). Serial pharmacokinetic studies showed that continuous daily RA treatment was associated with a marked decrease in plasma drug concentrations at the time of relapse compared with the initial day of therapy. Doubling the RA dose in six patients failed to reinduce response at the time of relapse and also failed to significantly augment plasma RA concentrations. However, leukemic cells obtained at the time of relapse from four patients retained in vitro sensitivity to the differentiating activity of RA (10(-6) mol/L). No change was observed in the pattern of PML/RAR-alpha expression assessed by Northern blot analysis at the time of relapse compared with pretreatment in two patients who were tested. These results indicate that clinical relapse and "resistance" to continuous treatment with all-trans RA in APL is associated with progressive reduction of plasma concentrations, potentially to levels below those that sustain differentiation of leukemic cells in vivo. Long-term success of this treatment will require the development of strategies that circumvent this pharmacologic phenomenon.

Carrier Proteins↗
PubMed1992

Retinoic acid and its rearranged receptor in the etiology and treatment of acute promyelocytic leukemia.

All-trans retinoic acid can induce complete remissions in patients with acute promyelocytic leukemia. The balanced chromosomal translocation t(15;17)(q22;q12-21) of this malignancy is now known to involve the nuclear retinoic acid receptor-alpha (RAR-alpha) on the long arm of chromosome 17 and a novel gene on the long arm of chromosome 15, designated PML (previously called myl). A unique fusion mRNA, PML/RAR-alpha, is produced. Paradoxically, this rearrangement of RAR-alpha results in clinical sensitivity to retinoic acid. Despite its efficacy, retinoic acid therapy has side effect, including a syndrome of hyperleukocytosis and respiratory distress in some patients. Remissions induced and maintained by continuous all-trans-retinoic treatment are not durable in most of these patients. Retinoic acid therapy for acute promyelocytic leukemia represents a unique example where a molecular defect may be involved both in the pathogenesis and treatment of a malignancy.

Animals↗
PubMed1991

Chromosomal translocation t(15;17) in human acute promyelocytic leukemia fuses RAR alpha with a novel putative transcription factor, PML.

A unique mRNA produced in leukemic cells from a t(15;17) acute promyelocytic leukemia (APL) patient encodes a fusion protein between the retinoic acid receptor alpha (RAR alpha) and a myeloid gene product called PML. PML contains a cysteine-rich region present in a new family of apparent DNA-binding proteins that includes a regulator of the interleukin-2 receptor gene (Rpt-1) and the recombination-activating gene product (RAG-1). Accordingly, PML may represent a novel transcription factor or recombinase. The aberrant PML-RAR fusion product, while typically retinoic acid responsive, displays both cell type- and promoter-specific differences from the wild-type RAR alpha. Because patients with APL can be induced into remission with high dose RA therapy, we propose that the nonliganded PML-RAR protein is a new class of dominant negative oncogene product. Treatment with RA would not only relieve this inhibition, but the activated PML-RAR protein may actually promote myelocyte differentiation.

Amino Acid Sequence↗
PubMed1991

Differentiation therapy of acute promyelocytic leukemia with tretinoin (all-trans-retinoic acid).

BACKGROUND AND METHODS: Patients with acute promyelocytic leukemia have a characteristic (15;17) translocation, with a breakpoint on chromosome 17 in the region of the retinoic acid receptor-alpha (RAR-alpha). Since this receptor has been shown to be involved with growth and differentiation of myeloid cells in vitro, and since recent clinical studies have reported that tretinoin (all-trans-retinoic acid) induces complete remission in patients with acute promyelocytic leukemia we studied the effects of tretinoin on cellular maturation and molecular abnormalities in patients undergoing the induction of remission with this agent. RESULTS: Eleven patients with acute promyelocytic leukemia were treated with tretinoin administered orally at a dose of 45 mg per square meter of body-surface area per day. Nine of the 11 patients entered complete remission. In two patients, complete remission was preceded by striking leukocytosis that then resolved despite continued drug treatment. Serial studies of cellular morphologic features, cell-surface immunophenotypic analysis, and fluorescence in situ hybridization with a chromosome 17 probe revealed that clinical response was associated with maturation of the leukemic clone. All patients who responded to treatment who were tested by Northern blot analysis had expression of aberrant RAR-alpha. As patients entered complete remission, the expression of the abnormal RAR-alpha message decreased markedly; however, it was still detectable in several patients after complete morphologic and cytogenetic remission had been achieved. CONCLUSIONS: Tretinoin is a safe and highly effective agent for inducing complete remission in patients with acute promyelocytic leukemia. Clinical response to this agent is associated with leukemic-cell differentiation and is linked to the expression of an aberrant RAR-alpha nuclear receptor. Molecular detection of the aberrant receptor may serve as a useful marker for residual leukemia in patients with this disease.

Administration, Oral↗
PubMed1985

Carbonic anhydrase is aberrantly and constitutively expressed in both human and murine erythroleukemia cells.

The levels of the erythrocyte proteins carbonic anhydrase (CA) and hemoglobin (Hb) change coordinately during human ontogeny. To further probe the coordinate gene expression of these two proteins in vitro, we used an immunoblotting technique to measure their levels during erythroid differentiation in normal human and murine erythroid progenitors, in human and murine erythroleukemia cells, and in normal murine erythroid progenitors infected with Friend virus. Levels of CA and Hb seem to gradually increase in normal differentiating stem cells. In contrast, both human and murine erythroleukemia cells show high levels of CA, but not of Hb, prior to induction of differentiation. Friend virus infection of normal murine progenitors appears to stimulate CA synthesis as an initial and integral step in transformation. In addition, both the erythroleukemia cells and the erythroid progenitors transformed with Friend virus seem to contain much higher levels of CA than Hb during the early stages of differentiation. This relationship is in marked contrast to normal erythroid differentiation, in which Hb levels are always higher than CA levels. Thus, neoplastic transformation seems to be associated with aberrant production of CA that does not correspond to a maturation arrest of the normal differentiation sequence.

Animals↗