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Genetics of recurrent PDX

Purpose:Glioblastoma is the most frequent and lethal primary brain tumor. Development of novel therapies relies on the availability of relevant preclinical models. We have established a panel of 96 glioblastoma patient-derived xenografts (PDX) and undertaken its genomic and phenotypic characterization.Experimental Design:PDXs were established from glioblastoma, IDH-wildtype (n = 93), glioblastoma, IDH-mutant (n = 2), diffuse midline glioma, H3 K27M-mutant (n = 1), and both primary (n = 60) and recurrent (n = 34) tumors. Tumor growth rates, histopathology, and treatment response were characterized. Integrated molecular profiling was performed by whole-exome sequencing (WES, n = 83), RNA-sequencing (n = 68), and genome-wide methylation profiling (n = 76). WES data from 24 patient tumors was compared with derivative models.Results:PDXs recapitulate many key phenotypic and molecular features of patient tumors. Orthotopic PDXs show characteristic tumor morphology and invasion patterns, but largely lack microvascular proliferation and necrosis. PDXs capture common and rare molecular drivers, including alterations of TERT, EGFR, PTEN, TP53, BRAF, and IDH1, most at frequencies comparable with human glioblastoma. However, PDGFRA amplification was absent. RNA-sequencing and genome-wide methylation profiling demonstrated broad representation of glioblastoma molecular subtypes. MGMT promoter methylation correlated with increased survival in response to temozolomide. WES of 24 matched patient tumors showed preservation of most genetic driver alterations, including EGFR amplification. However, in four patient–PDX pairs, driver alterations were gained or lost on engraftment, consistent with clonal selection.Conclusions:Our PDX panel captures the molecular heterogeneity of glioblastoma and recapitulates many salient genetic and phenotypic features. All models and genomic data are openly available to investigators.

Figures S1-S8, Supplementary Methods, Supplementary Bibliography

OBJECTIVE: To test whether crowdsourced lay raters can accurately assess cataract surgical skills. DESIGN: Two-armed study: independent cross-sectional and longitudinal cohorts. SETTING: Washington University Department of Ophthalmology. PARTICIPANTS AND METHODS: Sixteen cataract surgeons with varying experience levels submitted cataract surgery videos to be graded by 5 experts and 300+ crowdworkers masked to surgeon experience. Cross-sectional study: 50 videos from surgeons ranging from first-year resident to attending physician, pooled by years of training. Longitudinal study: 28 videos obtained at regular intervals as residents progressed through 180 cases. Surgical skill was graded using the modified Objective Structured Assessment of Technical Skill (mOSATS). Main outcome measures were overall technical performance, reliability indices, and correlation between expert and crowd mean scores. RESULTS: Experts demonstrated high interrater reliability and accurately predicted training level, establishing construct validity for the modified OSATS. Crowd scores were correlated with (r = 0.865, p < 0.0001) but consistently higher than expert scores for first, second, and third-year residents (p < 0.0001, paired t-test). Longer surgery duration negatively correlated with training level (r = −0.855, p < 0.0001) and expert score (r = −0.927, p < 0.0001). The longitudinal dataset reproduced cross-sectional study findings for crowd and expert comparisons. A regression equation transforming crowd score plus video length into expert score was derived from the cross-sectional dataset (r2 = 0.92) and demonstrated excellent predictive modeling when applied to the independent longitudinal dataset (r2 = 0.80). A group of student raters who had edited the cataract videos also graded them, producing scores that more closely approximated experts than the crowd. CONCLUSIONS: Crowdsourced rankings correlated with expert scores, but were not equivalent; crowd scores overestimated technical competency, especially for novice surgeons. A novel approach of adjusting crowd scores with surgery duration generated a more accurate predictive model for surgical skill. More studies are needed before crowdsourcing can be reliably used for assessing surgical proficiency.

Shakespeare Offstage: Drama and Cultural Currency, 1603-1660 argues that the Shakespearean theater played a foundational role in the formation of the public sphere. Historians locate the origin of the public sphere in the mass circulation of political polemics that came to a head in the 1640s. For literary historians, the Interregnum years are precisely the period that "forgot" Shakespeare. Neither discipline probes the extent of the connection between the theater and the popular press. By contrast, I argue that the institution of the professional theater, and Shakespeare's plays in particular, helped to create the public sphere and remained vitally important to the shaping of political discourse during the tumultuous 1640s and 50s. Many plays by Shakespeare and his contemporaries both prompt reflection on political questions and manipulate affective responses to them, linking the development of political subjecthood with emotional subjectivity. Increasingly, the theater became the forum in which the populace could participate in political discussions, a situation intensified by the absence of a Parliament between 1629 and 1640. The 1642 closure of the theaters, following the outbreak of civil war, was accompanied by a surge in popular print, relocating the public engagement that had taken place in the playhouse to the conceptual space of the public sphere. Shakespeare Offstage contends that you cannot get to a post-Restoration "public" without probing the connection between the drama of early seventeenth century and the activities of the popular press during the years 1640 to 1660. Appropriately, then, my dissertation is divided into three sections each of which approach the topic from distinct perspectives on the stage-page continuum. The first, "Textual Currency" explores the centrality of political texts to the theater by relating several plays by Shakespeare and his contemporaries to King James's popular writings on kingship. It shows how, in Measure for Measure, King Lear, and Macbeth, Shakespeare complicates his audience's response to doctrinally "correct" behavior by making it dramatically and emotionally less desirable. Chapter 1, "It's Not Easy Being King: Debunking 'Praejudged Conceits' in Measure for Measure," illustrates how several plays from 1604, by Shakespeare, Thomas Middleton, and John Marston, respond to James's Basilikon Doron and initiate an ongoing exchange between the Stuart monarchy and the theater. I argue that, in contrast to other "disguised duke" plays, Measure is concerned not to exhibit, propagate, or challenge James's ruling ideology, but to dramatize the difficulties experienced by the ruler in the face of public scrutiny and to engage with James's pressing desire, above all, to be understood by his subjects. Chapter 2, "Sovereign Remedy?: Healing the Body Politic in King Lear and Macbeth," analyzes two plays that portray the disastrous consequences of splitting the king's two bodies. Placing James's speeches concerning the union of Scotland and England alongside contemporary medical tracts, the chapter shows how Shakespeare dramatizes the dangers posed to the kingdom by a disordered monarchical body and offers a solution, a "sovereign remedy," tempering counsel in the case of Lear, bloodletting for Macbeth. The second section, "Theatrical Currency" interrogates our notions of "influence" and argues that our conception of quotation is insufficient to understand the strain of intertextuality central to the repertory theater system. Focusing on the close-knit and competitive character of the repertory theater, the chapters in this section illustrate the practice of inter-repertory borrowing, first from plays onstage, as in the case of city comedies, and second from recently printed playbooks of closet drama, where plays draw inspiration from recently printed copies of older drama. Chapter 3, "Tragedy Tomorrow, Comedy Tonight!: The Anti-Shakespearean Spirit of City Comedy," considers the drama produced for boys' companies (the main competition of the King's Men from 1600-1608) and illustrates how the genre of city comedy was shaped in reaction to dramatic conventions developed by Shakespeare and other senior playwrights. Using plays by Thomas Dekker, John Webster, Ben Jonson, and Middleton, I chronicle the boys' efforts to distinguish themselves through the incorporation, and parody, of dramatic styles and specific plays associated with the adult companies. Chapter 4, "Old Plays, New Sheets: Writing for Readers of Playbooks," presents three case studies of new plays with a telling subtext drawn from recently-reprinted older drama. It reads Middleton and William Rowley's The Changeling (1622) in relation to Othello and James Shirley's The Traitor (1631) and The Politician (1640) alongside Richard III and Richard II. It argues, more broadly, that writing for readers of playbooks produced drama that invites and rewards literary-critical engagement from its audience.My third and final section synthesizes theatrical and textual approaches in its exploration of "The Currency of Theatrical Texts." The chapters in this section focus on the force exerted by the printed playbooks that continued to be read and circulated in the decades after their publication, particularly during the period when the theaters were closed. They explore, in the first instance, non-dramatic popular literature produced between 1640 and 1660 and, in the second, dramatic texts, old and new, circulating during the same period. Chapter 5, "The Company Plays Keep: The Theatrical Legacy in Non-Dramatic Popular Print," discusses the popular printed brethren of the playbook--newsbooks, speeches, and polemics--and demonstrates that on the side of both production and consumption plays kept company with texts that were explicitly political. Chapter 6, "Theater Without Theaters: Drama in Print, 1642-1660," analyzes drama written after the closure of the theaters and finds in the highly politicized, often anonymous "pamphlet plays" the preservation and invocation of popular theatrical tradition.My dissertation concludes with a coda that considers what new direction the study of drama in the 1640-60 period might take. I posit that the closure of the theaters solidified a tradition of reading drama and transformed it into the dominant mode of engagement with plays. I propose a material history of reading drama, including plans for a searchable database of playbook marginalia, to help restore a missing piece of literary and theatrical history. I conclude by hypothesizing that the interregnum years witnessed the creation of a new literary culture surrounding plays distinct from that which existed prior to 1642 which certified their status as "literature" and which continues to inform our perception of plays as primarily texts to be read.

Purpose: Glioblastoma is the most frequent and lethal primary brain tumor. Development of novel therapies relies on the availability of relevant preclinical models. We have established a panel of 96 glioblastoma patient-derived xenografts (PDX) and undertaken its genomic and phenotypic characterization. Experimental Design: PDXs were established from glioblastoma, IDH-wildtype (n = 93), glioblastoma, IDH-mutant (n = 2), diffuse midline glioma, H3 K27M-mutant (n = 1), and both primary (n = 60) and recurrent (n = 34) tumors. Tumor growth rates, histopathology, and treatment response were characterized. Integrated molecular profiling was performed by whole-exome sequencing (WES, n = 83), RNA-sequencing (n = 68), and genome-wide methylation profiling (n = 76). WES data from 24 patient tumors was compared with derivative models. Results: PDXs recapitulate many key phenotypic and molecular features of patient tumors. Orthotopic PDXs show characteristic tumor morphology and invasion patterns, but largely lack microvascular proliferation and necrosis. PDXs capture common and rare molecular drivers, including alterations of TERT, EGFR, PTEN, TP53, BRAF, and IDH1, most at frequencies comparable with human glioblastoma. However, PDGFRA amplification was absent. RNA-sequencing and genome-wide methylation profiling demonstrated broad representation of glioblastoma molecular subtypes. MGMT promoter methylation correlated with increased survival in response to temozolomide. WES of 24 matched patient tumors showed preservation of most genetic driver alterations, including EGFR amplification. However, in four patient–PDX pairs, driver alterations were gained or lost on engraftment, consistent with clonal selection. Conclusions: Our PDX panel captures the molecular heterogeneity of glioblastoma and recapitulates many salient genetic and phenotypic features. All models and genomic data are openly available to investigators.

This collaborative self-study examines the influence of engagement in the core practices movement on the course designs, instruction, and perspectives of three novice teacher educators at a large mid-Atlantic research university. Through core practices work, we integrated repeated cycles of analysis, practice, and reflection into our courses, ultimately becoming more deliberate and responsive in our planning. We engaged in more in-depth inquiry into our teaching as we inquired into the core practices with our teacher candidates and also noticed an enhanced use of shared language. Core practices work influenced our perspectives on the work of teacher educators by reaffirming our belief in the complexity of teaching and teacher education, raising important questions about the relationship between commitments and core practices and underscoring the value of learner-centered practices in teacher education. The finding of this self-study suggest that core practices present an opportunity to engage novi...

INTRODUCTION Neuroimaging dogma for glioblastoma asserts that hyperintensity on T1Gd MRI reveals the bulk of the tumor, while T2/FLAIR signal indicates edema. However, it is unclear whether this edema results from immune response or increased tumor cells. Further, one significant driver of the known sex differences in glioblastoma may be differences in immune response, due to the X-linkage of many immune genes. Based on this, we hypothesized that assumptions regarding tumor cellularity in T2/FLAIR images should be tailored to the biological sex of the patient. METHODS Using a retrospective cohort of 18 primary glioblastoma patients receiving multiple image-localized biopsies (82 total) and standard MRI, we assessed: distance of biopsy from T1Gd and T2 areas; a pathologist’s score of percent tumor cell density; and an imaging-based invasion metric, D/ρ. This metric is derived from the biomathematical Proliferation-Invasion model of glioma growth, which features two parameters, net growth rate (ρ) and net invasion rate (D). Their ratio D/ρ is related to degree of invasion, and is estimated from volumetric measurements of MRI abnormalities. Additionally, 25 patient-derived xenograft models implanted in females were grown until moribund, at which point brains were excised and stained for DAPI (to show all cells) and Lamin (to highlight tumor cells). Image processing of lamin-stained sections defines contours of intensity correlating with cell density. RESULTS Outside both the T1Gd and T2 region, male patient biopsies had higher tumor cell densities than females. Males also tended to have higher invasion metrics. Although each set derived from different patients, preclinical metrics of invasion were positively correlated with clinical invasion in females but negatively correlated in males. CONCLUSION Our preliminary finding that cell distribution patterns correlate with imaging metrics differently between the sexes supports the hypothesis that the degree of tumor cell density represented on certain MRI sequences may be sex-specific.