Outcomes of human immunodeficiency virus-associated Burkitt lymphoma and diffuse large B-cell lymphoma treated in Australia: A report from the Australasian Lymphoma Alliance.

Antiretroviral therapy (ART) has improved outcomes for human immunodeficiency virus-associated non-Hodgkin lymphoma (HIV-NHL). This is an analysis of 44 patients with HIV with Burkitt lymphoma (HIV-BL) and diffuse large B-cell lymphoma (HIV-DLBCL) treated in Australia over a 10-year period (2009-2019) during the ART and rituximab era. At HIV-NHL diagnosis, the majority of presenting patients had adequate CD4 counts and undetectable HIV viral load <50 copies/mL. More than 80% of patients received chemotherapy with curative intent, rituximab, and concurrent ART with chemotherapy (immunotherapy). R-CODOX-M/IVAC or R-Hyper-CVAD (55%) were most commonly used in HIV-BL. CHOP (58%) was the most commonly used chemotherapy backbone for HIV-DLBCL, although 45% of patients received more intense chemotherapy regimens. Overall, 93% of patients who received curative therapy completed their intended course. The 2-year progression-free survival (PFS) and overall survival (OS) for the HIV-BL cohort was 67% and 67% respectively. The 2-year PFS and OS for the HIV-DLBCL cohort was 77% and 81% respectively. Treatment related mortality was 5%. In all, 83% of patients achieved a CD4 count of >0.2 ×109 /L 6 months after the end of treatment. Current Australian practice favours the treatment of HIV-BL and HIV-DLBCL similarly to the HIV-negative population with the use of concurrent ART, achieving outcomes comparable to the HIV-negative population.

Single cell enhancer activity distinguishes GABAergic and cholinergic lineages in embryonic mouse basal ganglia.

Enhancers integrate transcription factor signaling pathways that drive cell fate specification in the developing brain. We paired enhancer labeling and single-cell RNA-sequencing (scRNA-seq) to delineate and distinguish specification of neuronal lineages in mouse medial, lateral, and caudal ganglionic eminences (MGE, LGE, and CGE) at embryonic day (E)11.5. We show that scRNA-seq clustering using transcription factors improves resolution of regional and developmental populations, and that enhancer activities identify specific and overlapping GE-derived neuronal populations. First, we mapped the activities of seven evolutionarily conserved brain enhancers at single-cell resolution in vivo, finding that the selected enhancers had diverse activities in specific progenitor and neuronal populations across the GEs. We then applied enhancer-based labeling, scRNA-seq, and analysis of in situ hybridization data to distinguish transcriptionally distinct and spatially defined subtypes of MGE-derived GABAergic and cholinergic projection neurons and interneurons. Our results map developmental origins and specification paths underlying neurogenesis in the embryonic basal ganglia and showcase the power of scRNA-seq combined with enhancer-based labeling to resolve the complex paths of neuronal specification underlying mouse brain development.

Parallel functional testing identifies enhancers active in early postnatal mouse brain.

Enhancers are cis-regulatory elements that play critical regulatory roles in modulating developmental transcription programs and driving cell-type-specific and context-dependent gene expression in the brain. The development of massively parallel reporter assays (MPRAs) has enabled high-throughput functional screening of candidate DNA sequences for enhancer activity. Tissue-specific screening of in vivo enhancer function at scale has the potential to greatly expand our understanding of the role of non-coding sequences in development, evolution, and disease. Here, we adapted a self-transcribing regulatory element MPRA strategy for delivery to early postnatal mouse brain via recombinant adeno-associated virus (rAAV). We identified and validated putative enhancers capable of driving reporter gene expression in mouse forebrain, including regulatory elements within an intronic CACNA1C linkage disequilibrium block associated with risk in neuropsychiatric disorder genetic studies. Paired screening and single enhancer in vivo functional testing, as we show here, represents a powerful approach towards characterizing regulatory activity of enhancers and understanding how enhancer sequences organize gene expression in the brain.

Zanubrutinib for the treatment of Waldenström Macroglobulinemia.

Introduction: Waldenström Macroglobulinaemia (WM) is a heterogeneous, incurable condition which often relapses after chemoimmunotherapy. Novel therapies such as Bruton tyrosine-kinase (BTK) inhibitors have shown to be efficacious in treating WM but with an established, significant toxicity profile seen in the first-generation inhibitor Ibrutinib. Zanubrutinib is a selective, potent BTK inhibitor with the potential to reduce toxicity and improve efficacy. Areas covered: This review examines the activity of Zanubrutinib in treating treatment-naïve and relapsed refractory WM and it's toxicity profile when compared to Ibrutinib. Outcomes from the AU003 and ASPEN studies will be examined in detail including a particular focus on MYD88WT and CXCR4WHIM disease. Strengths and weaknesses of this treatment approach will be highlighted and future directions for research will be identified. Expert opinion: Zanubrutinib induces deeper responses and have greater activity in MYD88WT and CXCR4WHIM WM. Zanubrutinib also has a favorable toxicity profile when compared to Ibrutinib. This may potentially translate to lower discontinuation rates, improved quality of life and ultimately longer progression-free survival in patients with WM.

Regulatory Elements Inserted into AAVs Confer Preferential Activity in Cortical Interneurons.

Cortical interneuron (CIN) dysfunction is thought to play a major role in neuropsychiatric conditions like epilepsy, schizophrenia and autism. It is therefore essential to understand how the development, physiology, and functions of CINs influence cortical circuit activity and behavior in model organisms such as mice and primates. While transgenic driver lines are powerful tools for studying CINs in mice, this technology is limited in other species. An alternative approach is to use viral vectors such as AAV, which can be used in multiple species including primates and also have potential for therapeutic use in humans. Thus, we sought to discover gene regulatory enhancer elements (REs) that can be used in viral vectors to drive expression in specific cell types. The present study describes the systematic genome-wide identification of putative REs (pREs) that are preferentially active in immature CINs by histone modification chromatin immunoprecipitation and sequencing (ChIP-seq). We evaluated two novel pREs in AAV vectors, alongside the well-established Dlx I12b enhancer, and found that they drove CIN-specific reporter expression in adult mice. We also showed that the identified Arl4d pRE could drive sufficient expression of channelrhodopsin for optogenetic rescue of behavioral deficits in the Dlx5/6+/- mouse model of fast-spiking CIN dysfunction.

An evaluation of Ibrutinib for the treatment of Waldenstrom macroglobulinaemia.

INTRODUCTION: Waldenstrom Macroglobulinaemia (WM) is a heterogenous condition which poses a challenge to manage. Novel therapies such as Ibrutinib have been shown to be efficacious in treating WM. The landscape of Ibrutinib's role in treating WM is everchanging with new discoveries in disease genomics and evolution together as well as through new findings in clinical trials. AREAS COVERED: A systematic literature review was carried out using two databases 'Medline' and 'Embase' from 2009 to July 2019. Keywords used included 'Ibrutinib,' 'Waldenstrom Macroglobulinaemia,' and 'lymphoma.' There were four major clinical trials identified primarily describing outcomes of Ibrutinib in managing WM which this paper evaluates in detail. The authors present evidence of the role of Ibrutinib in the management of specific complications associated with WM. They also explore the recently discovered genomics of the disease affecting response to therapy. EXPERT OPINION: The evidence for the use of Ibrutinib as a treatment option for relapsed/refractory WM is compelling in MYD88 mutated WM with the response and survival rates potentially better than conventional salvage chemoimmunotherapy. There is also a case for it to be used in the frontline setting in patients unfit for conventional frontline chemoimmunotherapy.

Prognostic factors and the impact of frontline therapy in peripheral T-cell lymphoma: 10 years of 'real-world' experience from Western Australia.

We present an analysis of 98 consecutive patients with peripheral T-cell lymphoma (PTCL) treated over a 10-year period within Western Australia. The most common frontline therapies were CHO(E)P (47%), HyperCVAD (21%), and reduced intensity therapy or supportive care alone (19%). Median and 4-year overall survival (OS) for the whole cohort were 1.59 years and 34%. Amongst CHO(E)P and HyperCVAD-treated patients, elevated LDH, advanced stage, IPI >1, and non-ALK + ALCL histology predicted inferior progression-free survival (PFS). Inferior OS was predicted by elevated LDH, age >60, IPI >1, and non-ALK + ALCL histology. Response rates and PFS were not significantly different between patients treated with CHO(E)P or HyperCVAD. OS was longer in the HyperCVAD group, however this was not significant on multivariable analysis and appears to relate to the younger age and more aggressive therapy at relapse in this group. Our data confirmed the prognostic utility of the IPI in patients with PTCL and do not demonstrate a clear benefit of HyperCVAD.