Outcome in adolescent and young adult (AYA) patients compared with younger patients treated for high-risk B-precursor acute lymphoblastic leukemia (HR-ALL): A report from the Children’s Oncology Group study AALL0232

CRA9508

Background: Historically, AYA patients (>16yrs of age) with HR-ALL have an inferior outcome compared to HR-ALL patients 1-15 yrs old, due to increased rates of both relapse and toxicity. Methods: AALL0232 was a phase III randomized trial for patients 1-30 years of age with newly diagnosed B-precursor HR-ALL that utilized a 2 x 2 factorial design with an augmented intensity Berlin-Frankfurt-Münster (BFM) backbone. Patients were randomized to receive dexamethasone versus prednisone during Induction and high dose methotrexate versus escalating Capizzi methotrexate during Interim Maintenance I. A total of 2,574 eligible, evaluable, non-Down Syndrome, non-very high risk patients were randomized between January 2004 and January 2011. AYA patients comprised 20% of this group (n=501; 16-21 yrs: 466 and 22-30 yrs: 35). Results: The 5-yr event-free survival (EFS) and overall survival (OS) rates were 68.0% and 79.8% for AYA patients compared to 80.9% and 88.4% for younger patients (p<0.0001). The 5-yr cumulative incidence of relapse was 21.3% for AYA patients and 13.4% for younger patients (p=0.0018), largely due to higher rate of marrow relapse (15.2% vs. 9.0%; p<0.0007) and not CNS relapse (5.2% vs. 3.7%; p=0.5776). In addition, fewer AYA patients achieved remission, defined as <5% marrow blasts at end induction (97.2% vs. 98.8%; p=0.0134). There was no significant difference in induction mortality between AYA and younger patients, 2.4% vs. 1.8% (p=0.36). However post-induction remission deaths were significantly higher in AYA compared with younger patients, 5.5% vs. 2.1% at 5 years (p<0.0001). Conclusions: This is the largest cohort of AYA ALL patients presented to date and confirms high cure rates for AYA patients treated on pediatric ALL trials. AYA HR-ALL patients had lower EFS and OS compared to younger patients, primarily attributable to both higher rates of marrow relapses and remission deaths. Effective strategies to improve the outcome of AYA patients with HR-ALL should be aimed at both furthering leukemia eradication and lowering toxicity of therapy for this patient population.

Outcome in adolescent and young adult (AYA) patients compared with younger patients treated for high-risk B-precursor acute lymphoblastic leukemia (HR-ALL): A report from the Children’s Oncology Group study AALL0232

CRA9508

The full, final text of this abstract will be available at abstract.asco.org at 12:01 AM (EDT) on Saturday, June 2, 2012, and in the Annual Meeting Proceedings online supplement to the June 20, 2012, issue of Journal of Clinical Oncology. Onsite at the Meeting, this abstract will be printed in the Saturday edition of ASCO Daily News.

Stanford V chemotherapy and involved field radiotherapy for children and adolescents with unfavorable risk Hodgkin lymphoma: Results of a multi-institutional prospective clinical trial

9502

Background: To evaluate the efficacy of 12 weeks of Stanford V chemotherapy (prednisone, vinblastine, doxorubicine, nitrogen mustard, etoposide, vincristine, and bleomycin) without routine growth factor support plus response-adapted low-dose, involved-field radiotherapy (IFRT) in children and adolescents with unfavorable risk Hodgkin lymphoma (HL). Methods: Multi-institutional (St. Jude Children’s Research Hospital, Stanford University, Children’s Hospital Boston, Massachusetts General Hospital and Maine Children’s Hospital) clinical trial. One hundred forty-one patients with clinical stages IIB (n=43), IIIB (n=19), IVA (n=27), and IVB (n=52) HL were treated with 12 weeks of Stanford V chemotherapy and low dose IFRT between June 2002 and May 2011. Involved nodal sites in complete remission (CR, defined as > 75% shrinkage of the original tumor and PET negative) after 8 weeks of Stanford V received 15 Gy IFRT; those sites that achieved only partial response received 25.5 Gy IFRT after completion of all 12 weeks of chemotherapy. Results: With a median follow-up of 4.6 years, the 3-year overall and event-free survival (EFS) are 97% (SE=2%) and 79% (SE=4%) respectively. There was no significant difference in EFS by stage (IIB vs. IIIB vs. IV; P=0.84). Ten patients developed progessive disease and 18 relapsed, while 5 have died (1 after relapse in an accident and 4 of refractory disease). Most common toxicities were grade 3 hematologic with 234 episodes of neutropenia in 101 patients (72%) and 85 episodes of anemia in 52 patients (37%); Fever and neutropenia occurred 13 times in 12 patients (9%). Conclusions: Risk-adapted, combined-modality therapy using 12 weeks of Stanford V chemotherapy plus IFRT is well tolerated in this population with manageable acute toxicities. Overall survival is comparable to other more intense chemotherapy regimens. Future high-risk front line therapies may consider a Stanford V backbone with targeted intensification and further tailoring of radiation therapy.

Differential effects of falcarinol and related aliphatic C(17)-polyacetylenes on intestinal cell proliferation

Quantitative major polyacetylenes of carrots (falcarinol and falcarindiol) and American ginseng roots (falcarinol and panaxydol) were isolated and tested in human intestinal epithelial cells of normal (FHs 74 Int.) and cancer (Caco-2) origin. A hormesis effect was seen for all isolated polyacetylenes when added to Caco-2 cells in concentrations ranging from 1 ng/mL to 20 microg/mL. The relative inhibitory potency was falcarinol > panaxydol > falcarindiol. No hormesis effect was observed when adding the polyacetylenes to FHs 74 Int. cells. Instead, an inhibitory growth response was observed above 1 microg/mL. The relative inhibitory potency was panaxydol > falcarinol > falcarindiol. Maximal inhibition at 20 microg/mL corresponded to approximately 95% and 80% inhibition of cell proliferation in normal and cancer cells, respectively. Combinations of falcarinol and falcarindiol added to normal and cancer cells showed a synergistic response for the inhibition of cell growth. Furthermore, the oxidized form of falcarinol, falcarinon, showed a significantly less growth inhibitory effect in intestinal cells of both normal and cancer origin; hence, a hydroxyl group at C-3 may be important for activity of falcarinol-type polyacetylenes. Extracts of carrots, containing different amounts of falcarinol, falcarindiol, and falcarindiol 3-acetate had significant inhibitory effects on both normal and cancer cell proliferation. In cancer cells, the extract containing the highest concentration of falcarinol tended to have the highest growth inhibitory effect, in accordance with a higher potency of falcarinol than falcarindiol. The present study demonstrates that aliphatic C(17)-polyacetylenes are potential anticancer principles of carrots and related vegetables and that synergistic interaction between bioactive polyacetylenes may be important for their bioactivity.

Thallium intoxication treated with long-term hemodialysis, forced diuresis and Prussian blue

A 56-year-old woman, who ingested 2 g of thallium sulfate, was successfully treated with long-term hemodialysis for 200 hours during ten days, combined with forced diuresis and Prussian blue. The effect of the artificial kidney dialysis was determined by repeated analysis of the thallium concentration in the dialysis bath and in blood samples. During the first 120 hours of hemodialysis, 143 mg of thallium was eliminated via the artificial kidney and 110 mg via the urinary tract. The present case of acute thallium intoxication is the first in which long-term hemodialysis has been used in the acute phase together with forced diuresis and Prussian blue. The data obtained are compared to those obtained from cases treated with hemodialysis in the past. It is concluded that treatment with hemodialysis should be considered as an important supplement to treatment with forced diuresis and Prussian blue in cases of thallium intoxication.

Genome instability and DNA damage accumulation in gene-targeted mice

Six major pathways for DNA repair have been identified. These include (1) DNA repair by direct reversal, (2) base excision repair, (3) mismatch repair, (4) nucleotide excision repair, (5) homologous recombination, and (6) non-homologous end-joining. In addition, several other cellular processes influence the response to DNA damage. The generation of gene-targeted organisms is crucial for assessing the relative contribution of single DNA repair proteins and DNA repair pathways in maintaining genome stability. In particular, the accumulation of DNA damage, mutations and cancer in unexposed gene-targeted animals illuminates the spontaneous load of a particular lesion and the relative significance of a single gene in a specific pathway. Strategies for the generation of gene-targeted mice have been available for 15 years and more than 100 different genes relevant to DNA repair have been targeted. This review describes some important progress made toward understanding spontaneous DNA damage and its repair, exemplified through one, or a few, gene-targeted mice from each major DNA repair pathway.

Repair and mutagenesis at oxidized DNA lesions in the developing brain of wild-type and Ogg1-/- mice

OGG1 (8-oxoguanine DNA glycosylase-1) is one of the main DNA glycosylases present in mammalian cells. The enzyme removes 7,8-dihydro-8-oxoguanine (8-oxoG) lesions, believed to be the most important oxidized lesions due to their relatively high incidence and their miscoding properties. This study shows that in prenatal mice brains the repair capacity for 8-oxoG is 5-10-fold higher than in adult mice brains. Western blot analysis and repair activity in extracts from Ogg1(-/-) mice revealed that OGG1 was responsible for the efficient 8-oxoG removal from prenatal mice. To investigate how OGG1 protects against oxidative stress-induced mutagenesis, pregnant Big Blue/wild-type and Big Blue/Ogg1(-/-) mice were exposed to nontoxic doses of gamma radiation. A 2.5-fold increase in the mutation frequency in Ogg1(-/-) mouse brains was obtained by exposure to 3.5 Gy at day 19 postfertilization. This was largely due to GC to TA transversions, believed to originate from 8-oxoG mispairing with A during replication. Furthermore, rapid cell divisions seemed to be required for fixation of mutations, as a similar dose of radiation did not increase the mutation frequency, or the frequency of GC to TA transversion, in the adult brain.

Progression of kidney dysfunction in the community-dwelling elderly

Despite the high prevalence of chronic kidney disease among the elderly, few studies have described their loss of kidney function. We sought to determine the progression of kidney dysfunction among a community-based cohort of elderly subjects. The cohort included 10 184 subjects 66 years of age or older, who had one or more outpatient serum creatinine measurements during each of two time periods: 1 July to 31 December 2001 and 1 July to 31 December 2003. A mixed effects model, including covariates for age, gender, diabetes mellitus, and comorbidity, was used to determine the rate of decline in estimated glomerular filtration rate (eGFR, in ml/min/1.73 m2) per year over a median follow-up of 2.0 years. Subjects with diabetes mellitus had the greatest decline in eGFR of 2.1 (95% CI 1.8-2.5) and 2.7 (95% CI 2.3-3.1) ml/min/1.73 m2 per year in women and men, respectively. The rate of decline for women and men without diabetes mellitus was 0.8 (95% CI 0.6-1.0) and 1.4 (95% CI 1.2-1.6) ml/min/1.73 m2 per year. Subjects with a study mean eGFR<30 ml/min/1.73 m2, both those with and without diabetes mellitus, experienced the greatest decline in eGFR. In conclusion, we found that the majority of elderly subjects have no or minimal progression of kidney disease over 2 years. Strategies aimed at slowing progression of kidney disease should consider underlying risk factors for progression and the negligible loss of kidney function that occurs in the majority of older adults.

Quantification of biofilms in a sub-surface flow wetland and their role in nutrient removal

Subsurface flow wetlands contain gravel or sand substrates through which the wastewater flows vertically or horizontally. The aims of this study were, firstly, to quantify biofilm development associated with different size gravel in sections of a subsurface flow wetland with and without plants, and secondly, to conduct laboratory experiments to examine the role of biofilms in nutrient removal. Techniques to quantify biofilm included: bacterial cell counts, EPS and total protein extraction. Based on comparative gravel sample volume, only EPS was greater on the smaller 5 mm gravel particles. There was no significant difference between biofilm growth in sections with and without plants. Two vertical flow laboratory-scale reactors, one containing fresh wetland gravel, the other containing autoclaved gravel, were constructed to determine nutrient transformations. The autoclaved gravel in the "sterile" reactor rapidly became colonised with biofilm. Both reactors were dosed with two types of influent. Initially the influent contained 7.25 mg/L NO3-N and 0.3 mg/L NH4-N; the biofilm reactor removed most of the ammonium and nitrite but nitrate concentrations were only reduced by 20%. In the "sterile" reactor there was negligible removal of ammonium and nitrite indicating little nitrification, however nitrate was reduced by 72%, possibly due to assimilatory nitrate reduction associated with new biofilm development. When the influent contained 3 mg/L NO3-N and 16 mg/L NH4-N almost 100% removal and transformation of NH4-N occurred in both reactors providing an effluent high in NO3-N. Organic P was reduced but inorganic soluble P increased possibly due to mineralisation.

Are entrenched characters developmentally constrained? Creating biramous limbs in an insect

Are evolutionarily entrenched phenotypes highly constrained developmentally? We explored this question in the case of the uniramous appendages of fruit flies. We created bi- and polyramous antenna/leg combinations in four different genotypes. Each genotype consisted of two relevant mutations. We suggest that not all entrenched characters are strongly constrained by developmental processes and that there exists sufficient natural genetic variation to alter highly conserved phenotypes.