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PCR is widely used to measure minimal residual disease (MRD) in lymphoid neoplasms, but its sensitivity is limited. High Adenine/Thymine PCR and High Annealing Temperature PCR (HAT-PCR) is a modified PCR designed to minimize nonspecificity and hence increase sensitivity. It was evaluated in the laboratory and the clinic, using samples from 58 patients. Of these patients, 57 were adolescents or young adults who were participating in the Australasian Leukemia and Lymphoma Group ALL06 trial in which MRD was measured in blood principally by HAT-PCR and in marrow by conventional PCR. HAT-PCR produced significantly less nonspecificity than conventional PCR, and its limit of detection was10

Neuroblastoma is a frequently lethal childhood tumor in which MYC gene deregulation, commonly as MYCN amplification, portends poor outcome. Identifying the requisite biopathways downstream of MYC may provide therapeutic opportunities. We used transcriptome analyses to show that MYCN-amplified neuroblastomas have coordinately deregulated myriad polyamine enzymes (including ODC1, SRM, SMS, AMD1, OAZ2, and SMOX) to enhance polyamine biosynthesis. High-risk tumors without MYCN amplification also overexpress ODC1, the rate-limiting enzyme in polyamine biosynthesis, when compared with lower-risk tumors, suggesting that this pathway may be pivotal. Indeed, elevated ODC1 (independent of MYCN amplification) was associated with reduced survival in a large independent neuroblastoma cohort. As polyamines are essential for cell survival and linked to cancer progression, we studied polyamine antagonism to test for metabolic dependence on this pathway in neuroblastoma. The Odc inhibitor α-difluoromethylornithine (DFMO) inhibited neuroblast proliferation in vitro and suppressed oncogenesis in vivo. DFMO treatment of neuroblastoma-prone genetically engineered mice (TH-MYCN) extended tumor latency and survival in homozygous mice and prevented oncogenesis in hemizygous mice. In the latter, transient Odc ablation permanently prevented tumor onset consistent with a time-limited window for embryonal tumor initiation. Importantly, we show that DFMO augments antitumor efficacy of conventional cytotoxics in vivo. This work implicates polyamine biosynthesis as an arbiter of MYCN oncogenesis and shows initial efficacy for polyamine depletion strategies in neuroblastoma, a strategy that may have utility for this and other MYC-driven embryonal tumors. [Cancer Res 2008;68(23):9735–45]

Supplementary Figure 3 from ODC1 Is a Critical Determinant of MYCN Oncogenesis and a Therapeutic Target in Neuroblastoma

Supplementary Figure 1 from ODC1 Is a Critical Determinant of MYCN Oncogenesis and a Therapeutic Target in Neuroblastoma

Supplementary Figure Legends 1-3 from ODC1 Is a Critical Determinant of MYCN Oncogenesis and a Therapeutic Target in Neuroblastoma

IKZF1 deletions are associated with an increased risk of relapse in B-cell precursor acute lymphoblastic leukemia (B-ALL), and their accurate detection has great clinical impact. Here, we included four international cohorts of pediatric and adult patients with B-ALL, and reviewed literature to illustrate the recombination map of IKZF1 deletions, with a focus at non-recurrent deletions. We provide a substantial basis for the improvement of diagnostic methods based on MLPA and multiplex PCR for the identification of IKZF1 deletions, and also demonstrate that rare IKZF1 deletions increase the incidence of relapse in these patients. Of note, non-recurrent deletions comprised a wide range of alterations, but the majority were Δ1 and Δ1–3. They were often associated with reciprocal IKZF1 fusions. So far, a total of 23 IKZF1 gene fusions were identified in B-ALL. We also verified the occurrence of the heptamer sequence (E-value: 9.9 x 10− 9) and an enrichment of GC nucleotides (71% versus 56%; P value = 4.9 x 10− 3) exclusively within breakpoint clusters, suggesting that RAG recombination and TdT activity may promote the majority of IKZF1 deletions, although rare types of alterations may be associated with other molecular mechanism of leukemogenesis, such as microhomology-mediated end joining.

The advent of pediatric inspired regimens has improved the outcome for younger adults with Acute Lymphoblastic Leukemia (ALL), however this comes at a considerable toxicity burden limiting its applicability in older adults. The advent of novel immunotherapies, such as Blinatumomab, an anti-CD19 targeting Bi-specific T-cell engager, has improved outcomes for adults with relapsed refractory and minimal residual disease (MRD) positive B-precursor (BCP) ALL. The Australasian Leukemia and Lymphoma Group (ALLG) undertook a phase 2 proof-of-concept study to explore the combination of Blinatumomab with reduced intensity chemotherapy in adults with newly diagnosed Ph- BCP ALL. Patients received an initial pre-phase of corticosteroids (Prednisolone 100mg/d, 5 days) followed by a low intensity chemotherapy debulking (Cyclophosphamide 150mg/m 2 BD D1-3, Vincristine 2mg IV D1, 11 and Dexamethasone 10mg/m 2 D1-4, D11-14). Following this patients received Blinatumomab at 9mcg/d days 1-7 and 28mcg/d days 8-28. A B cycle of Hyper-CVAD (Cytarabine 3g/m 2 BD for 4 doses and Methotrexate 1g/m 2 D1 with Methylprednisolone 50mg BD D1-3). Patients then received 3 alternating cycles of Blinatumomab (28mcg/d for 28 days) and B-cycles of Hyper-CVAD followed by 2-years of POMP maintenance in subjects not proceeding to allogeneic stem cell transplant (alloHSCT) which was at investigator discretion. MRD assessments by ASO-PCR were performed after the first B cycle, second B cycle and prior to maintenance therapy with an MRD response being a level of 10 -4 or less. This analysis is from a pre-specified interim analysis with a data cutoff of 29 th June 2021. 30 patients were enrolled with a median age of 51.7(range, 39.5 - 66.5 years) with 70% male subjects. ECOG performance score was 0 in 14 subjects, 1 in 12 and 2 in 4. High risk disease was identified in 5 subjects (1 t(4;11), 2 hypodiploid, 1 t(1;19) and 1 Ph-like). All patients attained a CR, with 28 at end of 1B and a further 2 at end of 2B. Of 26 patients evaluable for MRD, 70% had achieved an MRD response after cycle 1B and 83% at the end of cycle 2B. 15 patients have ceased study therapy; 6 patients died with progressive disease, 4 subjects exited to allogeneic stem cell transplant, 1 patient was withdrawn due to progressive disease, 1 had intolerable toxicity (peripheral neuropathy) and 1 at investigator discretion. There were no treatment related deaths. 15 remain on protocol in maintenance with the remainder having completed therapy. At data cut-off the median event free survival (EFS) was not reached (95% CI 8.3 months - NA) with an estimated 24 month EFS of 61.8% (95% CI 36.3 - 84.2%) (figure 1A), and similarly the median overall survival (OS) S was not reached (95% CI 21.0 months - NA) with an estimated 24 month OS of 68.6% (95% CI 41.5 - 85.1%)(figure 1B). This predicted EFS was greater than the pre-specified stopping rule of a 24-month EFS of 50%. 2 episodes of cytokine release syndrome (CRS) were recorded (1 grade 2, 1 grade 3) with the major toxicity being infective (53 episodes of sepsis, infection or febrile neutropenia) predominately related to chemotherapy cycles. 7 episodes of neurological toxicity were demonstrated (1 myelopathy and 4 peripheral neuropathy occurring during chemotherapy and 2 encephalopathy occurring during Blinatumomab administration). Overall, the combination of Blinatumomab with chemotherapy was tolerable and appeared efficacious with a high rate of remission and deep MRD responses observed. Responses appeared durable despite a low rate of alloHSCTin first remission. The major toxicity was infective and occurred in the context of chemotherapy cycles. Future developments from this protocol will emphasise further reduction in cytotoxic chemotherapy through incorporation of further novel agents to minimise this toxicity. Figure 1 Figure 1. Disclosures Fleming: Servier: Honoraria; Pfizer: Honoraria, Speakers Bureau; Abbvie: Honoraria, Speakers Bureau; Amgen: Honoraria, Research Funding, Speakers Bureau. Reynolds: Abbvie: Research Funding; Novartis AG: Current equity holder in publicly-traded company; Alcon: Current equity holder in publicly-traded company. Bajel: Abbvie, Amgen, Novartis, Pfizer: Honoraria; Amgen: Speakers Bureau. Yeung: BMS: Honoraria, Research Funding; Pfizer: Honoraria; Amgen: Honoraria; Novartis: Honoraria, Research Funding. Verner: Janssen-Cilag Pty Ltd: Research Funding. Wei: Abbvie, Amgen, Astellas, AstraZeneca, Celgene/BMS, Genentech, Janssen, MacroGenics, Novartis, Pfizer, and Servier: Honoraria; Novartis, Abbvie, Celgene/BMS: Speakers Bureau; Servier: Consultancy; Abbvie, Amgen, AstraZeneca, Celgene/BMS, Novartis, Servier and F. Hoffmann-La Roche: Research Funding; Abbvie, Amgen, Astellas, AstraZeneca, Celgene/BMS, Genentech, Janssen, MacroGenics, Novartis, Pfizer, and Servier: Membership on an entity's Board of Directors or advisory committees; Former employee of Walter and Eliza Hall Institute: Patents & Royalties: Prof. Andrew Wei is a former employee of the Walter and Eliza Hall Institute and is eligible for a fraction of the royalty stream related to Venetoclax. Greenwood: Jazz Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees; Servier: Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees, Research Funding. OffLabel Disclosure: Blinatumomab - usage in front-line therapy for Acute Lymphoblastic Leukaemia

Introduction : Acknowledging informed consent and warning of material risk, the present study examined the current debate regarding early discussion of Sudden Unexplained Death in Epilepsy (SUDEP). It sought to confirm the profile of those prone to SUDEP and to determine the basis for disclosure to patients. Methods : Patients with SUDEP attending an Australian outpatient epilepsy clinic between 1985 and 2000 were compared to an age, gender and epilepsy type cross-matched control group to ascertain risk factors for SUDEP and similarities to published parameters. These were evaluated as the basis for actions in negligence for either disclosure or failure to disclose. Results : Twenty-one SUDEP patients were identified: aged 18–70 years; the majority had localisation-related epilepsy (13:8, 62%); male to female ratio was 3:1; and 15/21 used polypharmacy, compared with 8/21 controls ( P =0.02951). Handedness, alcohol use or deterioration of epilepsy were unrelated. Discussion : This population mirrored the literature and confirmed an absence of risk factors amenable to modification. As discussion of SUDEP with males with localisation-related epilepsy on polypharmacy could not alter outcome it is unlikely that failure to disclose could be causal and hence successful in an action for negligence. Conversely, disclosure, in the absence of the patient seeking the information, may causally adversely affect quality of life hence providing successful action in negligence. Duty of care dictates open and frank discussion with those seeking the information. Thus, each case must be managed individually and doctors are advised to document the decision-making process.