Citations

Abstract Durable overall response rate (ORR) remains a meaningful endpoint in recurrent GBM; however, the target ORR for single arm recurrent GBM trials has not been based on historic information or tied to patient outcomes. The current study reviewed past trials in recurrent GBM in order to judiciously define target ORRs for use in recurrent GBM trials. After reviewing 69 treatment arms comprising 4,971 patients, ORR was 6.1%[95% CI 4.23; 8.76%] for cytotoxic chemotherapies (ORR=7.59% for CCNU, 7.57% for TMZ, 0.64% for CPT-11, and 5.32% for other agents), 3.37% for biologic agents, 7.97% for immunotherapies (select trials), and 26.8% for anti-angiogenic agents. ORRs were significantly correlated with median overall survival (mOS) across chemotherapy (R2=0.4078, P< 0.0001), biologics (R2=0.4003, P=0.0003), and immunotherapy trials (R2=0.8994, P< 0.0001), but not anti-angiogenic agents (R2=0, P=0.8937). Pooling data from chemotherapy, biologics, and immunotherapy trials, a meta-analysis indicated a strong correlation between ORR and mOS (R2=0.3164, P< 0.0001; mOS[weeks]=0.6xORR+28.9), suggesting an ORR >20% results in an mOS of > 40.9 weeks, which is double the survival estimate of a treatment with ORR=0% and ≥ 2 months longer than treatments with ORR=5%. Assuming an ineffective therapy (control) has ORR=5%, a trial of 32 patients with a target ORR=20% leads to the 95% confidence interval higher than the control group. We conclude that single arm phase II studies in recurrent GBM with ≥ 32 patients should have a target ORR ≥ 20%. This was associated with a median OS of approximately 1 year. Importantly, durability of response should also be considered and was not assessed in the current meta-analysis.

Abstract Diffuse hemispheric glioma, H3 G34-mutant (DHG_H3G34) is a novel tumor type in the 2021 WHO CNS classification. We describe a comprehensive sequencing and high-resolution genome-wide copy number analysis of a series of cases clinically tested by a single laboratory (2018-2022). Cases included tumors from 47 unique patients (1 reportedly recurrent) that had an H3-3A G34 mutation detected using an 187-gene mutation and fusion targeted neuro-oncology NGS panel (n=47). A subset (n=18) of cases was also tested Oncoscan chromosomal microarray. Median age at testing was 20 years (range, 12-50). H3-3A G34 mutations included G34R (n=44; 94%), G34V (n=2) and a novel G34E variant considered to be likely clinically relevant (n=1). All DHG_H3G34 were hemispheric tumors, and one tumor was multifocal with midline involvement. Concurrent mutations recurrently involved ATRX (n=38), TERT promoter (n=3; mutually exclusive with ATRX mutations), TP53 (n=43), PDGFRA (n=26), PTEN (n=5), NF1 (n=4, all patients over 20 years), PIK3CA (n=4) and CDKN2A (n=3). The single recurrent tumor also had an MSH6 mutation, and in addition to 3 other cases, had increased number of sequence variants suggestive of a high tumor mutational burden. A single case also showed an FGFR3::FAM184B (exon 17::exon 2) fusion. All cases with available chromosomal microarray data had unbalanced genomes with multiple chromosomal gains/losses, and regions of copy-neutral loss of heterozygosity. The most frequent recurrent (at least 50% of cases) abnormalities were losses involving 3q, 4q, 10q, 13q and 18q, and 17p copy-neutral loss of heterozygosity encompassing TP53 (all but one case had concomitant TP53 mutation), a pattern reminiscent of IDH-mutant astrocytomas. Oncogene amplifications (PDGFRA and PIK3CA) were detected in 3 (of 18) cases. CDKN2A/B deletion was observed in 8 cases (2 homozygous). In conclusion, we describe additional sequence and copy-number abnormalities in DHG_H3G34, expanding the spectrum of genetic changes associated with this novel tumor type.

Previously we showed the generation of a protein trap library made with the gene-break transposon (GBT) in zebrafish ( Danio rerio ) that could be used to facilitate novel functional genome annotation towards understanding molecular underpinnings of human diseases (Ichino et al, 2020). Here, we report a significant application of this library for discovering essential genes for heart rhythm disorders such as sick sinus syndrome (SSS). SSS is a group of heart rhythm disorders caused by malfunction of the sinus node, the heart’s primary pacemaker. Partially owing to its aging-associated phenotypic manifestation and low expressivity, molecular mechanisms of SSS remain difficult to decipher. From 609 GBT lines screened, we generated a collection of 35 zebrafish insertional cardiac (ZIC) mutants in which each mutant traps a gene with cardiac expression. We further employed electrocardiographic measurements to screen these 35 ZIC lines and identified three GBT mutants with SSS-like phenotypes. More detailed functional studies on one of the arrhythmogenic mutants, GBT411 , in both zebrafish and mouse models unveiled Dnajb6 as a novel SSS causative gene with a unique expression pattern within the subpopulation of sinus node pacemaker cells that partially overlaps with the expression of hyperpolarization activated cyclic nucleotide gated channel 4 (HCN4), supporting heterogeneity of the cardiac pacemaker cells.

Context.— Plasmablastic lymphoma (PBL) is a rare aggressive lymphoma, usually positive for CD138 and frequently occurring in the oral cavity of human immunodeficiency virus (HIV) patients. Up to 10% of cases are negative for CD138 and diagnostically very challenging. Objective.— To investigate the appropriate approach to diagnose CD138− plasmablastic lymphoma and avoid misdiagnosis. Design.— We studied 21 cases of CD138− PBL from multiple large institutes in the United States and 21 cases from the literature. Results.— CD138− PBLs were positive for different B/plasma cell markers at various percentages: MUM1 (94.4%; 34 of 36), OCT2 (70.6%; 12 of 17), immunoglobulin light chains (68.8%; 22 of 32), CD38 (68.4%; 13 of 19), CD79a (34.2%; 13 of 38), and PAX5 (15.6%; 5 of 32), suggesting that MUM1, OCT2, immunoglobulin light chains, and CD38 are useful markers to help establish the lineage. A total of 83% of cases (30 of 36) were extraoral lesions. Extraoral lesions showed much lower Epstein-Barr virus (EBV) infection rates (16 of 30; 53.3%) and had worse prognosis. MYC was positive in 80% (8 of 10) of EBV+ cases and 40% (2 of 5) EBV− cases, indicating the importance of MYC in pathogenesis, especially in EBV+ cases. Conclusions.— Our study emphasizes that CD138− PBLs tend to be extraoral lesions, with much lower EBV infection rates, and diagnostically very challenging. Accurate diagnosis requires a thorough investigation and workup by using appropriate markers.

Abstract Peripheral T-cell lymphomas (PTCLs) are heterogenous T-cell neoplasms often associated with epigenetic dysregulation. We investigated de novo DNA methyltransferase 3A (DNMT3A) mutations in common PTCL entities, including angioimmunoblastic T-cell lymphoma and novel molecular subtypes identified within PTCL–not otherwise specified (PTCL-NOS) designated as PTCL-GATA3 and PTCL-TBX21. DNMT3A-mutated PTCL-TBX21 cases showed inferior overall survival (OS), with DNMT3A-mutated residues skewed toward the methyltransferase domain and dimerization motif (S881–R887). Transcriptional profiling demonstrated significant enrichment of activated CD8+ T-cell cytotoxic gene signatures in the DNMT3A-mutant PTCL-TBX21 cases, which was further validated using immunohistochemistry. Genomewide methylation analysis of DNMT3A-mutant vs wild-type (WT) PTCL-TBX21 cases demonstrated hypomethylation in target genes regulating interferon-γ (IFN-γ), T-cell receptor signaling, and EOMES (eomesodermin), a master transcriptional regulator of cytotoxic effector cells. Similar findings were observed in a murine model of PTCL with Dnmt3a loss (in vivo) and further validated in vitro by ectopic expression of DNMT3A mutants (DNMT3A-R882, -Q886, and -V716, vs WT) in CD8+ T-cell line, resulting in T-cell activation and EOMES upregulation. Furthermore, stable, ectopic expression of the DNMT3A mutants in primary CD3+ T-cell cultures resulted in the preferential outgrowth of CD8+ T cells with DNMT3AR882H mutation. Single-cell RNA sequencing(RNA-seq) analysis of CD3+ T cells revealed differential CD8+ T-cell subset polarization, mirroring findings in DNMT3A-mutated PTCL-TBX21 and validating the cytotoxic and T-cell memory transcriptional programs associated with the DNMT3AR882H mutation. Our findings indicate that DNMT3A mutations define a cytotoxic subset in PTCL-TBX21 with prognostic significance and thus may further refine pathological heterogeneity in PTCL-NOS and suggest alternative treatment strategies for this subset.

Background In participants with concomitant chronic coronary disease and advanced chronic kidney disease (CKD), the effect of treatment strategies on the timing of dialysis initiation is not well characterized. Methods and Results In ISCHEMIA‐CKD (International Study of Comparative Health Effectiveness With Medical and Invasive Approaches–Chronic Kidney Disease), 777 participants with advanced CKD and moderate or severe ischemia were randomized to either an initial invasive or conservative management strategy. Herein, we compare the proportion of randomized participants with non–dialysis‐requiring CKD at baseline (n=362) who initiated dialysis and compare the time to dialysis initiation between invasive versus conservative management arms. Using multivariable Cox regression analysis, we also sought to identify the effect of invasive versus conservative chronic coronary disease management strategies on dialysis initiation. At a median follow‐up of 23 months (25th–75th interquartile range, 14–32 months), dialysis was initiated in 18.9% of participants (36/190) in the invasive strategy and 16.9% of participants (29/172) in the conservative strategy (P= 0.22). The median time to dialysis initiation was 6.0 months (interquartile range, 3.0–16.0 months) in the invasive group and 18.2 months (interquartile range, 12.2–25.0 months) in the conservative group (P= 0.004), with no difference in procedural acute kidney injury rates between the groups (7.8% versus 5.4%; P =0.26). Baseline clinical factors associated with earlier dialysis initiation were lower baseline estimated glomerular filtration rate (hazard ratio [HR] associated with 5‐unit decrease, 2.08 [95% CI, 1.72–2.56]; P <0.001), diabetes (HR, 2.30 [95% CI, 1.28–4.13]; P =0.005), hypertension (HR, 7.97 [95% CI, 1.09–58.21]; P =0.041), and Hispanic ethnicity (HR, 2.34 [95% CI, 1.22–4.47]; P =0.010). Conclusions In participants with non–dialysis‐requiring CKD in ISCHEMIA‐CKD, randomization to an invasive chronic coronary disease management strategy (relative to a conservative chronic coronary disease management strategy) is associated with an accelerated time to initiation of maintenance dialysis for kidney failure. Registration URL: https://www.clinicaltrials.gov ; Unique identifier: NCT01985360.