Salvage of patients with relapsed and refractory Hodgkin disease (HD) with highdose chemoradiotherapy (HDT) and autologous stem cell transplantation (ASCT) results in event-free survival (EFS) rates from 30% to 50%. Unfortunately, the reduction in toxicity associated with modern supportive care has improved EFS by only 5% to 10% and has not reduced the relapse rate. Results of a comprehensive 2-step protocol encompassing dosedense and dose-intense second-line chemotherapy, followed by HDT and ASCT, are reported. Sixty-five consecutive patients, 22 with primary refractory HD and 43 with relapsed HD, were treated with 2 biweekly cycles of ifosfamide, carboplatin, and etoposide (ICE). Peripheral blood progenitor cells from responding patients were collected, and the patients were given accelerated fractionation involved field radiotherapy (IFRT) followed by cyclophosphamide-etoposide and either intensive accelerated fractionation total lymphoid irradiation or carmustine and ASCT. The EFS rate at a median follow-up of 43 months, as analyzed by intent to treat, was 58%. The response rate to ICE was 88%, and the EFS rate for patients who underwent transplantation was 68%. Cox regression analysis identified 3 factors before the initiation of ICE that predicted for outcome: B symptoms, extranodal disease, and complete remission duration of less than 1 year. EFS rates were 83% for patients with 0 to 1 adverse factors, 27% for patients with 2 factors, and 10% for patients with 3 factors (P < .
ICE chemotherapy, with ifosfamide administered as a 24-hour infusion to decrease CNS side effects, and the substitution of carboplatin for cisplatin to minimize nephrotoxicity, is a very effective cytoreduction and mobilization regimen in patients with NHL. Furthermore, the quality of the clinical response to ICE predicts for posttransplant outcome.
A B S T R A C T PurposeThis randomized, open-label trial compared dacomitinib (PF-00299804), an irreversible inhibitor of human epidermal growth factor receptors (EGFR)/HER1, HER2, and HER4, with erlotinib, a reversible EGFR inhibitor, in patients with advanced non-small-cell lung cancer (NSCLC). Patients and MethodsPatients with NSCLC, Eastern Cooperative Oncology Group performance status 0 to 2, no prior HER-directed therapy, and one/two prior chemotherapy regimens received dacomitinib 45 mg or erlotinib 150 mg once daily. ResultsOne hundred eighty-eight patients were randomly assigned. Treatment arms were balanced for most clinical and molecular characteristics. Median progression-free survival (PFS; primary end point) was 2.86 months for patients treated with dacomitinib and 1.91 months for patients treated with erlotinib (hazard ratio [HR] ϭ 0.66; 95% CI, 0.47 to 0.91; two-sided P ϭ .012); in patients with KRAS wild-type tumors, median PFS was 3.71 months for patients treated with dacomitinib and 1.91 months for patients treated with erlotinib (HR ϭ 0.55; 95% CI, 0.35 to 0.85; two-sided P ϭ .006); and in patients with KRAS wild-type/EGFR wild-type tumors, median PFS was 2.21 months for patients treated with dacomitinib and 1.84 months for patients treated with erlotinib (HR ϭ 0.61; 95% CI, 0.37 to 0.99; two-sided P ϭ .043). Median overall survival was 9.53 months for patients treated with dacomitinib and 7.44 months for patients treated with erlotinib (HR ϭ 0.80; 95% CI, 0.56 to 1.13; two-sided P ϭ .205). Adverse event-related discontinuations were uncommon in both arms. Common treatment-related adverse events were dermatologic and gastrointestinal, predominantly grade 1 to 2, and more frequent with dacomitinib. ConclusionDacomitinib demonstrated significantly improved PFS versus erlotinib, with acceptable toxicity. PFS benefit was observed in most clinical and molecular subsets, notably KRAS wild-type/EGFR any status, KRAS wild-type/EGFR wild-type, and EGFR mutants.
Purpose We sought to characterize the pharmacokinetics (PK) and determine a tolerable dose of oral sorafenib in patients with hepatic or renal dysfunction. Patients and Methods Patients were assigned to one of nine cohorts: cohort 1, bilirubin ≤ upper limit of normal (ULN) and AST ≤ ULN and creatinine clearance (CC) ≥ 60 mL/min; cohort 2, bilirubin more than ULN but ≤ 1.5× ULN and/or AST more than ULN; cohort 3, CC between 40 and 59 mL/min; cohort 4, bilirubin more than 1.5× ULN to ≤ 3× ULN (any AST); cohort 5, CC between 20 and 39 mL/min; cohort 6, bilirubin more than 3× ULN to 10× ULN (any AST); cohort 7, CC less than 20 mL/min; cohort 8, albumin less than 2.5 mg/dL (any bilirubin/AST); and cohort 9, hemodialysis. Sorafenib was administered as a 400-mg dose on day 1 for PK, and continuous daily dosing started on day 8. Results Of 150 registered patients, 138 patients were treated. With the exception of cohorts 6 and 7, at least 12 patients per cohort were assessable, and the dose level with prospectively defined dose-limiting toxicity in less than one third of patients by day 29 was considered tolerable. No significant associations between the sorafenib PK and cohort were found. Conclusion We recommend the following empiric sorafenib starting doses by cohort: cohort 1, 400 mg twice a day; cohort 2, 400 mg twice a day; cohort 3, 400 mg twice a day; cohort 4, 200 mg twice a day; cohort 5, 200 mg twice a day; cohort 6, not even 200 mg every third day tolerable; cohort 7, not defined; cohort 8, 200 mg each day; and cohort 9, 200 mg each day.
The mouse gene Krox-24 is transiently activated during cell cycle reentry. It encodes a protein with three zinc fingers similar to those of the transcription factor Sp1. Here we present a biochemical characterization of the gene products. Krox-24 mRNA is translated into two proteins of 82 and 88 kilodaltons, designated p82Krox-24 and p88Krox-24, respectively. p82Krox-24 is initiated at the first AUG codon of the open reading frame, whereas synthesis of p88Krox-24 starts at a non-AUG codon located upstream. Both proteins were synthesized in HeLa cells infected with recombinant vaccinia viruses expressing Krox-24 cDNAs. Under these conditions, they were found phosphorylated on serine residues and glycosylated. The availability of the proteins made possible the determination of the DNA recognition sequence. In vitro, Krox-24 bound specifically to the sequence 5'-GCG(C/G)GGGCG-3'. This sequence is similar but not identical to the Sp1 target sequence. Insertion of an oligomer for the binding site in cis, close to the herpes simplex virus thymidine kinase promoter, rendered this promoter responsive to Krox-24. Krox-24 is therefore a sequence-specific transcriptional activator. Krox-24-binding sites were found upstream of several serum-inducible genes, raising the possibility that Krox-24 is involved in the regulation of these genes.
To isolate transcription factors important in the regulation of the human interleukin-3 (IL-3) gene, we screened a gt11 cDNA library, constructed from phytohemagglutinin-stimulated human T-cell RNA, with a probe containing regulatory sequences in the upstream region of the IL-3 gene (located from bp ؊165 to ؊128 and referred to as the DNase I footprint A region). We isolated a 0.96-kb cDNA that encoded a basic amino acid domain and a leucine zipper domain and used the ''rapid amplification and cloning of 3 ends'' technique to isolate the 3 half of the cDNA clone, generating a 1.9-kb full-length cDNA clone. Using in vitro-translated protein, which we call NF-IL3A, we defined the IL-3 promoter sequences bound by NF-IL3A in DNase I footprinting assays as TAATTACGTCTG and, using gel shift assays, defined ATTACG as the minimal sequence Interleukin-3 (IL-3) is a multilineage hematopoietic growth factor which stimulates the proliferation of hematopoietic progenitor cells and enhances the functional activity of mature effector cells (27,36). The expression of IL-3 is restricted to activated, but not resting, T cells, natural killer (NK) cells, and mast cell lines (9,27,29). In order to examine the regulatory mechanisms controlling the expression of IL-3, several investigators, including ourselves, have identified regulatory elements in the 5Ј-flanking region of the IL-3 promoter (3,10,13,19,21,22,33,35). These regulatory elements include a consensus AP-1 binding site, which can bind c-Fos/c-Jun heterodimers (13), several consensus binding sites for ets proteins (13), a CD28 response element (12, 35), and two regions identified by DNase I footprinting experiments as the A region and the B region (35). The A region contains regulatory sequences important in the inducible expression of 33,35), and methylation interference experiments have identified several distinct regions within this A region that are involved in DNAprotein interactions (10, 37). Electrophoretic mobility shift assays (EMSAs) combined with UV cross-linking have identified several proteins of 56 to 65 kDa that are capable of binding to the IL-3 A region (37).To identify and characterize IL-3 A region-binding proteins, we screened a phytohemagglutinin (PHA)-stimulated human T-cell cDNA gt11 expression library with a 32 P-labeled, multimerized, double-stranded IL-3 A region synthetic oligonucleotide probe. Approximately one million recombinant clones were screened, and one clone that generated a -galactosidase fusion product that bound to the IL-3 A region but not to unrelated control DNA was identified. DNA sequence analysis of this clone demonstrated the presence of a potential DNAbinding basic-amino-acid region and a leucine zipper repeat. The 3Ј portion of the cDNA clone was not present, so rapid amplification and cloning of 3Ј ends (3Ј RACE) was performed to generate a full-length cDNA clone.A 1.9-kb full-length cDNA that contains the entire coding region for a 58-kDa protein that we call NF-IL3A was generated. In vitro-translated NF-IL3A binds specifi...
The AML1 and ETS families of transcription factors play critical roles in hematopoiesis; AML1, and its non-DNA-binding heterodimer partner CBFbeta, are essential for the development of definitive hematopoiesis in mice, whereas the absence of certain ETS proteins creates specific defects in lymphopoiesis or myelopoiesis. The promoter activities of numerous genes expressed in hematopoietic cells are regulated by AML1 proteins or ETS proteins. MEF (for myeloid ELF-1-like factor) is a recently cloned ETS family member that, like AML1B, can strongly transactivate several of these promoters, which led us to examine whether MEF functionally or physically interacts with AML1 proteins. In this study, we demonstrate direct interactions between MEF and AML1 proteins, including the AML1/ETO fusion protein, in t(8;21)-positive acute myeloid leukemia (AML) cells. Using mutational analysis, we identified a novel ETS-interacting subdomain (EID) in the C-terminal portion of the Runt homology domain (RHD) in AML1 proteins and determined that the N-terminal region of MEF was responsible for its interaction with AML1. MEF and AML1B synergistically transactivated an interleukin 3 promoter reporter gene construct, yet the activating activity of MEF was abolished when MEF was coexpressed with AML1/ETO. The repression by AML1/ETO was independent of DNA binding but depended on its ability to interact with MEF, suggesting that AML1/ETO can repress genes not normally regulated by AML1 via protein-protein interactions. Interference with MEF function by AML1/ETO may lead to dysregulation of genes important for myeloid differentiation, thereby contributing to the pathogenesis of t(8;21) AML.
SUMMARY Interleukin-6 (IL6) plays a central role in multiple myeloma pathogenesis and confers resistance to corticosteroid-induced apoptosis. We therefore evaluated the efficacy and safety of siltuximab, an anti-IL6 monoclonal antibody, alone and in combination with dexamethasone, for patients with relapsed or refractory multiple myeloma who had ≥2 prior lines of therapy, one of which had to be bortezomib-based. Fourteen initial patients received siltuximab alone, 10 of whom had dexamethasone added for suboptimal response; 39 subsequent patients were treated with concurrent siltuximab and dexamethasone. Patients received a median of 4 prior lines of therapy, 83% were relapsed and refractory, and 70% refractory to their last dexamethasone-containing regimen. Suppression of serum C-reactive protein levels, a surrogate marker of IL6 inhibition, was demonstrated. There were no responses to siltuximab but combination therapy yielded a partial (17%) + minimal (6%) response rate of 23%, with responses seen in dexamethasone-refractory disease. The median time to progression, progression-free survival and overall survival for combination therapy was 4.4, 3.7 and 20.4 months, respectively. Haematological toxicity was common but manageable. Infections occurred in 57% of combination-treated patients, including ≥grade 3 infections in 18%. Further study of siltuximab in modern corticosteroid-containing myeloma regimens is warranted, with special attention to infection-related toxicity.
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