An array of oncogenic histone point mutations have been identified across a number of different cancer studies. It has been suggested that some of these mutant histones can exert their effects by ...inhibiting epigenetic writers. Here, we report that the H3.3 G34R (glycine to arginine) substitution mutation, found in paediatric gliomas, causes widespread changes in H3K9me3 and H3K36me3 by interfering with the KDM4 family of K9/K36 demethylases. Expression of a targeted single-copy of H3.3 G34R at endogenous levels induced chromatin alterations that were comparable to a KDM4 A/B/C triple-knockout. We find that H3.3 G34R preferentially binds KDM4 while simultaneously inhibiting its enzymatic activity, demonstrating that histone mutations can act through inhibition of epigenetic erasers. These results suggest that histone point mutations can exert their effects through interactions with a range of epigenetic readers, writers and erasers.
This article thoroughly examines the crucial role of predictive analytics and fault tolerance mechanisms in enhancing the reliability of microelectronic devices throughout their design and ...manufacturing processes. Emphasizing the importance of implementing these measures across the entire lifecycle, including design, manufacturing, and application phases, the study adopts a comprehensive approach. The methodology integrates predictive analytics tools and fault tolerance mechanisms, proactively identifying and mitigating potential issues early on. Results demonstrate a significant reduction in device failures, showcasing the transformative impact of these technologies. Overall, the research advocates for the strategic integration of predictive analytics and fault tolerance mechanisms to advance the reliability of microelectronic devices across diverse applications.
Abstract Although current methods for measuring the concentration of transparent particles in digital holographic technology are effective, they involve complex procedures and require significant ...time and computational resources. The objective of this study was to accurately measure particle concentration from a single hologram. Deep learning was employed to measure the quantities of the particles of the same size, and we achieved a relative error less than 10% compared to the ground truth values. This indicates the potential to obtain results closely aligned with actual particle quantities without the reconstruction and denoising processes. The time needed for hologram prediction was at millisecond level, which offers a new possibility for real-time processing.
Measurable residual disease (MRD) testing is an essential aspect of disease prognostication in acute lymphoblastic leukaemia (ALL) and informs clinical decisions. The depth of MRD clearance is highly ...relevant and requires assays with sufficient sensitivity. Austin Pathology is one of the few laboratories in Australia currently utilising a fully validated and National Association of Testing Authorities (NATA)-accredited ultrasensitive next-generation sequencing (NGS) platform for MRD monitoring in ALL. This technology is based on the detection of clonal rearrangement of immunoglobulin and T cell receptor genes in leukaemic cells, and is capable of achieving a limit of detection at least one to two logs below that of multiparametric flow cytometry (MFC). In this retrospective analysis, we report a clonotype detection rate of up to 85.7% at diagnosis, and a concordance rate of 78.7% in MRD results between NGS and MFC. Of the discordant samples, nearly all were NGS+/MFC–, highlighting the superior sensitivity of NGS. The enhanced sensitivity is clinically relevant, as discordant MRD results often heralded fulminant relapse, and therefore offer clinicians additional lead time and a window of opportunity to initiate pre-emptive therapy. Notwithstanding a small and heterogeneous cohort, our real-world survival data indicate an intermediate relapse risk for NGS+/MFC– patients. In light of recent approval of Medicare rebatable ALL MRD testing, we discuss how NGS can complement other techniques such as MFC in personalising management strategies. We recommend routine clonality testing by NGS at diagnosis and use a multi-modality approach for subsequent MRD monitoring.
Immune evasion, due to abnormal expression of programmed-death ligands 1 and 2 (PD-L1/PD-L2), predicts poor outcomes with chemoimmunotherapy in diffuse large B-cell lymphoma (DLBCL). Immune ...checkpoint inhibition (ICI) has limited efficacy at relapse but may sensitise relapsed lymphoma to subsequent chemotherapy. ICI delivery to immunologically intact patients may thus be the optimal use of this therapy. In the phase II AvR-CHOP study, 28 patients with treatment-naive stage II-IV DLBCL received sequential avelumab and rituximab priming ("AvRp;" avelumab 10 mg/kg and rituximab 375 mg/m2 2-weekly for 2 cycles), R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, prednisolone for 6 cycles) and avelumab consolidation (10 mg/kg 2-weekly for 6 cycles). Grade 3/4 immune-related adverse events occurred in 11%, meeting the primary endpoint of a grade ≥3 irAE rate of <30%. R-CHOP delivery was not compromised but one patient ceased avelumab. Overall response rates (ORR) after AvRp and R-CHOP were 57% (18% CR) and 89% (all CR). High ORR to AvRp was observed in primary mediastinal B-cell lymphoma (67%; 4/6) and molecularly-defined EBV-positive DLBCL (100%; 3/3). Progression during AvRp was associated with chemorefractory disease. Two-year failure-free and overall survival were 82% and 89%. An immune priming strategy with AvRp, R-CHOP and avelumab consolidation shows acceptable toxicity with encouraging efficacy.
Introduction Bruton's tyrosine kinase inhibitors (BTKi) have improved 1 st line therapy efficacy in elderly (Wang NEJM 2022) and young, fit, MCL-the latter with intermittent dosing during RCHOP in an ...alternating RCHOP/cytarabine-based regimen (Dreyling Blood 2022). However direct combination of BTKi & intensive chemo is toxic in DLBCL studies. (Kuruvilla Haematol Oncol 2017). The highly selective BTKi, acalabrutinib (A), has proven efficacy and tolerability in relapsed MCL (Wang Lancet 2018). RDHAOx chemotherapy (rituximab, dexamethasone, cytarabine, oxaliplatin) prior to ASCT provides a complete response (CR) rate of 77% and favourable toxicity compared to many induction regimens (Le Gouill Blood 2017). Furthermore, Obinutuzumab-DHAP yields undetectable minimum residual disease (MRD) in 85% of young MCL patients. (Le Gouill Haematol Oncol 2019). Here we report the primary endpoint from the Australasian Leukaemia & Lymphoma Group phase 2 ‘WAMM’ trial exploring a ‘sandwich’ model of an acalabrutinib-rituximab (AR) ‘window’ before RDHAOx +/- ASCT, followed by fixed-duration AR-maintenance to improve therapy response and minimise additional toxicity. Methods NHL33'WAMM' (ACTRN12619000990123) is a multicentre single-arm phase 2 trial. Key eligibility included: age 18-70 years, untreated histologically-proven stage II-IV MCL, ECOG<2; no contraindications to ASCT or BTKi. Pts received 2 cycles of AR (AR window); ‘A’ dose; 100mg BD PO, ‘R’ dose; 375mg/m 2 IV (day 1) every 4 weeks, followed by RDHAOx x4 cycles. Those with an objective response (CR or partial response-PR) underwent BEAM ASCT (carmustine, etoposide, cytarabine, melphalan) then AR maintenance (A; 1yr continuous & R; 3-monthly x 8 cycles). Those who did not undergo BEAM ASCT were able to remain on study and proceed to maintenance AR in the event of ongoing response. Co-primary endpoints (EP) were safety; defined by lack of prohibitive toxicity causing treatment cessation AND PET-determined complete response (CR) rate after AR+RDHAOx. Secondary EP include overall response rates (ORR), toxicity, overall survival (OS) & progression-free survival (PFS), MRD negativity rates and quality of life. Only Grade 3+ toxicity related to acalabrutinib was collected during the ASCT period. Baseline whole exome sequencing was performed to identify mutations, MRD analysis was done by LymphoTrack® Dx and MRD Assay platform (Invivoscribe, Inc) using Illumina® MiSeq. This study was the first Australian blood cancer trial to use telehealth and a ‘hub-and-spoke’ transplant model. Results 44 pts were enrolled from Sept 2020 to Apr 2022 (43 evaluable for the primary endpoint). Baseline characteristics were typical of a young MCL cohort: median age 59 years (Interquartile range 54-64), 77% were male, ECOG was 0-1 in 98%, 84% had stage IV, lactate dehydrogenase was elevated in 35%, Ki-67 >30% in 66% and blastoid/pleomorphic histology 9%. TP53 by NGS will be reported at presentation. CR rate post AR+RDHAOx induction was 88%; (95%CI 72-95) with ORR 95% and no prohibitive toxicity. AR window ORR was 93% (CR 57%). MRD negativity was achieved in 18% (7/38) post AR window, and 94% (34/36) post RDHAOx. 43 patients remained evaluable for response after R-DHAOX and pre-maintenance with 35 (80%) who underwent ASCT and 38 (86%) who commenced AR maintenance; 7 remain on maintenance. Response in specific subgroups will be reported at the meeting. At data lock, 35 pts (81%) experienced ≥1 G3+ adverse events during induction or maintenance phases, most common were neutropenia (58% of pts), febrile neutropenia (27%), thrombocytopenia (25%), diarrhea (14%). No G5 treatment-related events have occurred to date. There have been 22 SAEs, most common were COVID (3), febrile neutropenia (2) and fever (2). 5 deaths have been reported: 4 in pts with progressive disease and 1 COVID pneumonitis during AR maintenance. After a median follow up of 22 months (range 17-28m), the 2-year OS was 89%. Analysis of survival, quality of life and biomarkers will be reported with more mature follow up. Conclusion AR delivered in a sandwich approach is active and safe. An AR window yields a high ORR and compared to historical studies, improves post-chemo induction CR rates and MRD negativity. A telehealth model allowed rapid recruitment in a rare cancer.
Abstract
Background: Most DLBCL & FL responds well to first line treatment, yet relapsed disease outcomes are poor. Immune checkpoint inhibition (ICI) with PD/PD1 inhibitors (PD1i) yield high ...response rates in some lymphomas; though single agent PD1i yields a disappointing ORR of 10% in heavily pre-treated DLBCL, some responses are durable. RT stimulates anti-tumour immunity through several mechanisms and may enhance response to ICI. Concurrent ICI & RT is synergistic in preclinical studies & solid tumours, improving local & distant (abscopal) response. RT to multiple disease sites may broaden the spectrum of tumour antigen release and overcome clonal variation between disease sites to further augment the immune response. A dose-response relationship between RT and antigen release has yet to be established. This phase I dose escalation study aims to determine the safety profile of RT in combination with durvalumab, an anti-PD-L1 monoclonal antibody, in relapsed/refractory DLBCL and FL.
Study Design and Methods: RaDD (NCT03610061) is a phase I dose escalation study to determine the safety profile of escalating dose and number of sites of RT in combination with durvalumab in relapsed/refractory (RR) DLBCL & FL. Eligible patients (pts) have received ≥ 1 prior line of therapy and are ineligible for or relapsed after autologous stem cell transplant (auto-SCT). Pts with active autoimmune disease, CNS involvement, prior allogeneic-SCT or chronic steroid use are excluded. RT dose and site escalation proceeds according to a 3+3 design with 6 dose levels (cohorts 1-6). Treatment comprises external beam RT to target site(s) daily for 5 days (Cohorts 1-5); Cohort 6 receives a further 5 daily fractions (max 30Gy). Durvalumab 1500mg IV commences day 2 of RT and continues 4-weekly until disease progression. Pts can continue until a second radiological progression if clinical benefit is ongoing. The dose limiting toxicity period is 28 days from start of RT.
The primary endpoint is the toxicity, drug pharmacokinetics, maximum tolerated dose (MTD) and recommended phase two dose (RP2D) of simultaneous RT and durvalumab. Secondary endpoints include response rates, progression-free survival and overall survival.
Correlative studies will examine the tumour-immune system interaction; an exploratory PET substudy with novel tracers for durvalumab (89Zr-Durvalumab) & CD8+ T cells (89Zr -Df-IAB22M2C) will also be performed.
Projected enrolment for determination of the MTD and RP2D is 6-30 pts pending toxicity. Recruitment will continue to 36 pts for secondary endpoint analysis. 22 pts are enrolled to date in the main study, with 2 patients enrolled in the PET-substudy.
Acknowledgements: Victorian Cancer Agency (grant funding - TRP16006), Astra Zeneca (durvalumab and funding), Celgene (funding), Imaginab (89Zr -Df-IAB22M2C).
Citation Format: Kate Manos, Richard Khor, Geoffrey Chong, Jodie Palmer, Michael MacManus, Colm Keane, Andrew M. Scott, Jake Shortt, David Ritchie, Leonid Churilov, Laura Johnston, Tom Witkowski, Allison Barraclough, Sze Ting Lee, Wendi Lin, Rachel Koldej, Eliza Hawkes. Phase I Dose Escalation Study of Radiotherapy and Durvalumab (MEDI4736) in Relapsed or Refractory Diffuse Large B-cell Lymphoma (DLBCL): The RaDD Study abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT208.
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TPS8075
Background: Most DLBCL & FL responds well to first line treatment, yet relapsed disease outcomes are poor. PD1/PDL1 inhibitors yield high response rates in some lymphomas, but ...single agent therapy in heavily pre-treated pts are disappointing. RT stimulates anti-tumor immunity through several mechanisms and may enhance response to immune checkpoint inhibition (ICI). Concurrent ICI & RT is synergistic in preclinical studies & solid tumors, improving local & distant (abscopal) response. RT to multiple disease sites may broaden the spectrum of tumor antigen release and overcome clonal variation between disease sites to further augment the immune response. Methods: RaDD (NCT03610061) is a phase I, 3+3 dose escalation study to determine the safety profile of escalating dose & number of sites of RT in combination with Durvalumab (anti-PD-L1 antibody) in RR DLBCL & FL. Eligible pts (i.e. ≥1 prior therapy, ineligible for auto-SCT, no contraindication to PDL1i) receive 5 fractions of external beam RT to target site(s). 5 RT dose & site levels are included (dose range 2.5Gy-20Gy to 1-3 sites). Durvalumab 1500mg IV commences day 2 of RT and continues 4-weekly until confirmed disease progression. The DLT period is 28 days from start of RT. Primary endpoint is the recommended phase two dose (RP2D) of RT in combination with durvalumab. Secondary endpoints include response rates, PFS & OS. Correlative studies will examine the tumour-immune system interaction; an exploratory PET substudy with novel tracers for durvalumab (
89
Zr-Durvalumab) & CD8+ T cells (
89
Zr -Df-IAB22M2C) will also be performed. Projected enrollment for determination of maximum tolerated dose (MTD) & RP2D is 6-30 pts pending toxicity. Recruitment will continue to 36 pts for secondary endpoint analysis. 9 pts are enrolled across cohorts 1-3 to date. Clinical trial information: NCT03610061 .
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