To determine the outcome of children with Down syndrome (DS) and acute myeloid leukemia (AML) receiving standard timing chemotherapy without bone marrow transplantation (BMT), with determination of ...prognostic factors.
Children with DS and newly diagnosed AML or myelodysplasia were prospectively enrolled on Children's Cancer Group study 2891 (N = 161) and treated uniformly with four standard timing induction courses of dexamethasone, cytarabine arabinoside, 6-thioguanine, etoposide, daunorubicin (DCTER) followed by intensively timed high-dose cytarabine.
Children with DS were significantly younger at diagnosis than those without (median age, 1.8 v 7.5 years, respectively; P <.001), with more megakaryocytic leukemia (70% v 6%; P <.001). Higher complete remission rates (91%) were achieved in children with DS than among those without DS (75%; P <.001). Equivalent grade 3 to 4 toxicity (29% v 30%; P =.84) was seen, though children with DS had greater pulmonary toxicity (P <.01) during induction and mucositis during intensification (P =.12). Children with DS had significantly better 8-year event-free survival (EFS; 77% v 21% standard and 40% intensive induction; P <.0001). Multivariate analysis in children with DS revealed that only age at diagnosis of 2 years or older was a risk factor for greater relapse risk (odds ratio, 4.9; P =.006) and worse survival. Children between ages 0 to 2 years (n = 94) had a 6-year EFS of 86%; those from 2 to 4 years (n = 58), 70%; and those older than 4 years (n = 9), 28%. Remission failures were the primary reason for worse 6-year EFSs (1% in those 0 to 2 years v 14% if >2 years; P =.002).
Outcome for children with DS and AML is excellent with standard induction therapy, but declines with increasing age.
We previously reported a benefit for all-trans retinoic acid (ATRA) in both induction and maintenance therapy in patients with acute promyelocytic leukemia (APL). To determine the durability of this ...benefit and identify important prognostic factors, long-term follow-up of the North American Intergroup APL trial is reported. A total of 350 patients with newly diagnosed APL were randomized to either daunorubicin and cytarabine (DA) or ATRA for induction and then either ATRA maintenance or observation following consolidation chemotherapy. The complete remission (CR) rates were not significantly different between the ATRA and DA groups (70% and 73%, respectively). However, the 5-year disease-free survival (DFS) and overall survival (OS) were longer with ATRA than with DA for induction (69% vs 29% and 69% vs 45%, respectively). Based on both induction and maintenance randomizations, the 5-year DFS was 16% for patients randomized to DA and observation, 47% for DA and ATRA, 55% for ATRA and observation, and 74% for ATRA and ATRA. There was no advantage of either induction regimen among any subgroups when CR alone was considered. However, female sex, classical M3 morphology (vs the microgranular variant M3v), and treatment–white blood cell count (WBC) interaction (ATRA/WBC below 2 × 109/L 2000/μL best, DA/WBC above 2 × 109/L worst) were each significantly associated with improved DFS (P < .05). Treatment with ATRA, WBC below 2 × 109/L, and absence of bleeding disorder were each significantly associated with improved OS. Age more than 15 years, female sex, and treatment-morphology interaction (DA/M3v worst, ATRA best regardless of morphology) were each significantly associated with improved DFS based on maintenance randomization. The improvement in outcome with ATRA in APL was maintained with long-term follow-up.
To compare the efficacy and safety of celecoxib, a cyclooxygenase-2 (COX-2) inhibitor, with those of naproxen, a nonsteroidal anti-inflammatory drug (NSAID), and placebo in the treatment of ...osteoarthritis of the knee.
In this multicenter, randomized, double-blind, placebo-controlled trial, 1003 patients with symptomatic osteoarthritis of the knee were randomly assigned to receive celecoxib at doses of 50, 100, or 200 mg twice a day; naproxen, 500 mg twice a day; or placebo for 12 weeks. Patients were evaluated with standard measures of efficacy 2 to 7 days after discontinuing previous NSAID or analgesic therapy and after 2, 6, and 12 weeks of treatment with the study drug.
Celecoxib treatment led to significant improvement in the signs and symptoms of osteoarthritis as determined by all efficacy measures. Significant pain relief occurred within 2 days of the initiation of treatment, and maximum anti-inflammatory and analgesic activity, evident within 2 weeks, was sustained throughout the 12-week study. All celecoxib doses were efficacious compared with placebo, although the 50-mg twice-daily dosage regimen was minimally effective. The higher doses of celecoxib (100 and 200 mg twice a day) were similarly efficacious, and the magnitude of improvement observed with these dosing regimens was comparable to that seen with naproxen at a dose of 500 mg twice a day. All doses of celecoxib and naproxen were well tolerated.
COX-2 inhibition with celecoxib is an effective approach for the treatment of osteoarthritis, as seen by clinical improvement in signs and symptoms comparable to treatment with naproxen.
Activating mutations of receptor tyrosine kinases (RTKs) and their downstream affectors are common in acute myeloid leukemia (AML). We performed mutational analysis of FLT3, c-kit, c-fms, vascular ...endothelial growth factor (VEGF) receptors (Flt-1, KDR kinase domain receptor), and ras genes in a group of 91 pediatric patients with AML treated on Children’s Cancer Group clinical trial CCG-2891. Forty-six percent of patients had activating mutations of FLT3 (24.5%), c-kit (3%), or ras (21%) genes. Mutation-positive patients had a higher median diagnostic white blood cell (WBC) count (71.5 vs 19.6 × 109/L; P = .005) and lower complete remission rate (55% versus 76%; P = .046) than mutation-negative patients. The Kaplan-Meier estimate of overall survival (OS) for patients with and without an activating mutation was 34% versus 57%, respectively (P = .035). However, within this group, patients with FLT3/ALM (activation loop mutation) had good outcomes (OS, 86%). Exclusion of the FLT3/ALM from analysis decreased the OS for the remaining mutation-positive patients to 26% (P = .003). Ten of the 23 mutation-positive and 11 of the 34 mutation-negative patients received an allogeneic bone marrow transplant (BMT) in first complete remission (CR). In the mutation-positive group, the disease-free survival (DFS) for the allogeneic BMT recipients was 72% versus 23% for the 13 patients who received chemotherapy or autologous BMT (P = .01). DFS for the mutation-free patients with and without allogeneic BM transplantation was 55% and 40%, respectively (P = .38). Activating mutations in the RTK/ras signaling pathway are common in pediatric AML, and their presence may identify a population at higher risk of poor outcome who may benefit from allogeneic BM transplantation.
Intensive, myelosuppressive therapy is necessary to maximize outcomes for patients with acute myeloid leukemia (AML). A comparison was made of 3 aggressive postremission approaches for children and ...adolescents with AML in a randomized trial, CCG-2891. A total of 652 children and adolescents with AML who achieved remission on 2 induction regimens using identical drugs and doses (standard and intensive timing) were eligible for allocation to allogeneic bone marrow transplantation (BMT) based on matched related donor status (n = 181) or randomization to autologous BMT (n = 177) or to aggressive high-dose cytarabine-based chemotherapy (n = 179). Only 115 patients (18%) refused to participate in the postremission phase of this study. Overall compliance with the 3 allocated regimens was 90%. At 8 years actuarial, 54% ± 4% (95% confidence interval) of all remission patients remain alive. Survival by assigned regimen (“intent to treat”) is as follows: allogeneic BMT, 60% ± 9%; autologous BMT, 48% ± 8%; and chemotherapy, 53% ± 8%. Survival in the allogeneic BMT group is significantly superior to autologous BMT (P = .002) and chemotherapy (P = .05); differences between chemotherapy and autologous BMT are not significant (P = .21). No potential confounding factors affected results. Patients receiving intensive-timing induction therapy had superior long-term survival irrespective of postremission regimen received (allogeneic BMT, 70% ± 9%; autologous BMT, 54% ± 9%; chemotherapy, 57% ± 10%). Allogeneic BMT remains the treatment of choice for children and adolescents with AML in remission, when a matched related donor is available. For all others, there is no advantage to autologous BMT; hence, aggressive nonablative chemotherapy should be used.
Robert J. Arceci, MD, PhD, 1950-2015 Woods, William G.; Lange, Beverly J.
Pediatric blood & cancer,
August 2015, Letnik:
62, Številka:
8
Journal Article
Survivin is a novel member of the inhibitor of apoptosis protein (IAP) family. Here we report that the chemotherapeutic drug doxorubicin, a DNA-damaging agent, activates a p53-survivin signaling ...pathway inducing cell cycle arrest and apoptosis in childhood acute lymphoblastic leukemia (ALL). Treatment of wild-type (wt) p53 ALL cells (EU-3 cell line) with doxorubicin caused accumulation of p53, resulting in dramatic down-regulation of survivin, depletion of cells in G(2)/M, and apoptosis (increased sub-G(1) compartment). In contrast, doxorubicin treatment of mutant (mut) p53 cells (EU-6/ALL line) up-regulated survivin and induced G(2)/M arrest without inducing apoptosis. However, treating EU-6 with anti-survivin antisense resensitized these cells to doxorubicin, resulting in apoptosis. With a p53-null cell line (EU-4), although doxorubicin treatment arrested cells in G(2)/M, survivin expression was unchanged, and cells underwent only limited apoptosis. However, re-expression of wt-p53 in EU-4 cells could restore the doxorubicin-p53-survivin pathway, resulting in significantly decreased survivin expression and increased apoptosis in these cells after doxorubicin treatment. Following cotransfection of p53-null EU-4 cells with survivin promoter-luciferase constructs and either wt-p53 or different mut-p53 expression vectors, wt-p53 inhibited survivin promoter activity; p53-mediated inhibition could be abrogated by overexpression of murine double minute2 (MDM2) protein. Together, these studies define a novel p53-survivin signaling pathway activated by DNA damage that results in down-regulation of survivin, cell cycle arrest, and apoptosis. Furthermore, our data indicate that loss of wt-p53 function in tumor cells may contribute to up-regulation of survivin and resistance to DNA-damaging agents.
PDF
