A novel class of inhibitors that disrupts the stability of integrin heterodimers identified by CRISPR-tiling-instructed genetic screens.

The plasma membrane is enriched for receptors and signaling proteins that are accessible from the extracellular space for pharmacological intervention. Here we conducted a series of CRISPR screens using human cell surface proteome and integrin family libraries in multiple cancer models. Our results identified ITGAV (integrin αV) and its heterodimer partner ITGB5 (integrin ß5) as the essential integrin α/ß pair for cancer cell expansion. High-density CRISPR gene tiling further pinpointed the integral pocket within the ß-propeller domain of ITGAV for integrin αVß5 dimerization. Combined with in silico compound docking, we developed a CRISPR-Tiling-Instructed Computer-Aided (CRISPR-TICA) pipeline for drug discovery and identified Cpd_AV2 as a lead inhibitor targeting the ß-propeller central pocket of ITGAV. Cpd_AV2 treatment led to rapid uncoupling of integrin αVß5 and cellular apoptosis, providing a unique class of therapeutic action that eliminates the integrin signaling via heterodimer dissociation. We also foresee the CRISPR-TICA approach to be an accessible method for future drug discovery studies.

Therapeutic targeting Tudor domains in leukemia via CRISPR-Scan Assisted Drug Discovery.

Epigenetic dysregulation has been reported in multiple cancers including leukemias. Nonetheless, the roles of the epigenetic reader Tudor domains in leukemia progression and therapy remain unexplored. Here, we conducted a Tudor domain-focused CRISPR screen and identified SGF29, a component of SAGA/ATAC acetyltransferase complexes, as a crucial factor for H3K9 acetylation, ribosomal gene expression, and leukemogenesis. To facilitate drug development, we integrated the CRISPR tiling scan with compound docking and molecular dynamics simulation, presenting a generally applicable strategy called CRISPR-Scan Assisted Drug Discovery (CRISPR-SADD). Using this approach, we identified a lead inhibitor that selectively targets SGF29's Tudor domain and demonstrates efficacy against leukemia. Furthermore, we propose that the structural genetics approach used in our study can be widely applied to diverse fields for de novo drug discovery.

Grounded Theory Approach to Understand Self-Management of Opioid Recovery Through Pregnancy and Early Parenting.

OBJECTIVE: To develop a theory to explain the processes women use to self-manage recovery from opioid use disorder during pregnancy, the postpartum period, and early parenting. DESIGN: Constructivist grounded theory approach. PARTICIPANTS: Women (N = 16) who gave birth during the past 12 months and used medication for opioid use disorder for recovery through pregnancy and the postpartum period. METHODS: We recruited participants through seven medication-assisted treatment clinics in a mid-size Midwestern city and the surrounding suburbs and through online parenting and recovery community groups with national-based memberships. We conducted semistructured, individual audio interviews from November 2020 to July 2021. Interviews continued until we reached theoretical and meaning saturation. We used constant comparative methods during initial and intermediate coding. RESULTS: Participants described a central process, Growing as a Healthy Dyad, that included six processes they used to self-manage recovery: Maintaining Vigilance, Performing Self-Care, Putting in the Work of Recovery, Advocating, Navigating Social Support, and Acquiring Skills and Knowledge. These processes were affected by personal and social contextual factors. CONCLUSIONS: The grounded theory, Self-Management of Opioid Recovery Through Pregnancy and Early Parenting, can be used to explain the unique processes of self-management by women in opioid recovery and highlights the need for a strengths-based approach to caring for the maternal-infant dyad.

Hallermann-Streiff Syndrome in Concordant Monozygotic Twins With Congenital Cataracts, Exudative Retinal Detachments, and One Case of Corneal Perforation Requiring Keratoplasty.

PURPOSE: We describe the management of Hallermann-Streiff syndrome in monozygotic female twins with congenital cataracts, exudative retinal detachments, and 1 case of corneal descemetocele with associated dellen and subsequent perforation. METHODS: This study was a case report and review of the literature. RESULTS: Twins 1 and 2 exhibited all 7 cardinal characteristics of Hallermann-Streiff syndrome, presenting with spontaneous lenticular resorption, anterior uveitis, and glaucoma. They underwent bilateral cataract extraction with near total capsulectomy. Both twins experienced recurrent glaucoma, for which twin 1 underwent successful endocyclophotocoagulation in both eyes and twin 2 in the left eye alone. The fellow eye developed 2 sites of perilimbal corneal descemetoceles with associated dellen at the inferotemporal limbal corneal junction leading to spontaneous perforation of 1 site, requiring a full-thickness corneal graft. Both twins developed recurrent bilateral exudative retinal detachments unresponsive to oral prednisolone. Twin 1's last best-corrected visual acuity with aphakic spectacles was 20/260 in the right eye and 20/130 in the left eye at age 4 years and 8 months. Twin 2's last best-corrected visual acuity was 20/130 in each eye at age 4 years and 11 months, over a year after right eye penetrating keratoplasty. CONCLUSIONS: We describe 2 rare cases of Hallermann-Streiff syndrome in monozygotic twins complicated by corneal perforation requiring penetrating keratoplasty in 1 eye of 1 twin. Although corneal opacities have been described in this condition, this is the first case of corneal descemetocele in Hallermann-Streiff syndrome. The cornea was stabilized with a relatively favorable visual outcome over 1 year later.

Epigenetic Control of Translation Checkpoint and Tumor Progression via RUVBL1-EEF1A1 Axis.

Epigenetic dysregulation is reported in multiple cancers including Ewing sarcoma (EwS). However, the epigenetic networks underlying the maintenance of oncogenic signaling and therapeutic response remain unclear. Using a series of epigenetics- and complex-focused CRISPR screens, RUVBL1, the ATPase component of NuA4 histone acetyltransferase complex, is identified to be essential for EwS tumor progression. Suppression of RUVBL1 leads to attenuated tumor growth, loss of histone H4 acetylation, and ablated MYC signaling. Mechanistically, RUVBL1 controls MYC chromatin binding and modulates the MYC-driven EEF1A1 expression and thus protein synthesis. High-density CRISPR gene body scan pinpoints the critical MYC interacting residue in RUVBL1. Finally, this study reveals the synergism between RUVBL1 suppression and pharmacological inhibition of MYC in EwS xenografts and patient-derived samples. These results indicate that the dynamic interplay between chromatin remodelers, oncogenic transcription factors, and protein translation machinery can provide novel opportunities for combination cancer therapy.

Engagement in Online Communities by New Mothers in Recovery from Opioid Use Disorder.

PURPOSE: The purpose of this study was to examine the role of engagement with online communities by women using medication-assisted treatment (MAT) to manage recovery from opioid use disorder (OUD) during pregnancy and the first year after birth. STUDY DESIGN AND METHODS: Ten participants were identified through purposive sampling for this secondary data analysis as part of a larger grounded theory study about ways women using MAT for recovery from OUD meet the needs of their mother-infant dyad. Inclusion criteria included: English-speaking, 18 years of age or older, living in the United States, within the first year after birth, using MAT to manage OUD, and identified engaging with online communities during pregnancy and/or postpartum. A categorical-content narrative approach was used. RESULTS: Three narratives were identified from the analysis, belonging , collaboration , and expecting success . CLINICAL IMPLICATIONS: Engagement in online communities can be a meaningful adjunct or replacement for in-person support. Online spaces are available 24/7 and allow people to join a community where they will not experience stigma and can find support tailored to their needs. Health care providers could extend their care for mothers affected by OUD by referring them to online communities for support of recovery self-management efforts.

ACTR5 controls CDKN2A and tumor progression in an INO80-independent manner.

Epigenetic dysregulation of cell cycle is a hallmark of tumorigenesis in multiple cancers, including hepatocellular carcinoma (HCC). Nonetheless, the epigenetic mechanisms underlying the aberrant cell cycle signaling and therapeutic response remain unclear. Here, we used an epigenetics-focused CRISPR interference screen and identified ACTR5 (actin-related protein 5), a component of the INO80 chromatin remodeling complex, to be essential for HCC tumor progression. Suppression of ACTR5 activated CDKN2A expression, ablated CDK/E2F-driven cell cycle signaling, and attenuated HCC tumor growth. Furthermore, high-density CRISPR gene tiling scans revealed a distinct HCC-specific usage of ACTR5 and its interacting partner IES6 compared to the other INO80 complex members, suggesting an INO80-independent mechanism of ACTR5/IES6 in supporting the HCC proliferation. Last, our study revealed the synergism between ACTR5/IES6-targeting and pharmacological inhibition of CDK in treating HCC. These results indicate that the dynamic interplay between epigenetic regulators, tumor suppressors, and cell cycle machinery could provide novel opportunities for combinational HCC therapy.

MicroRNA-148a-3p is a candidate mediator of increased bone marrow adiposity and bone loss following spinal cord injury.

Spinal cord injury is often followed by osteoporosis characterized by rapid and severe bone loss. This leads to an increased risk of osteoporotic fracture in people with spinal cord injury, resulting in increased healthcare costs, morbidity, and mortality. Though it is common, the mechanisms underlying this osteoporosis are not completely understood and treatment options are limited. No biomarkers have been identified for predicting fracture risk. In this study, we sought to investigate microRNA mediated mechanisms relating to osteoporosis following spinal cord injury. We studied subjects with acute SCI (n=12), chronic SCI (n=18), and controls with no SCI (n=23). Plasma samples from all subjects underwent transcriptomic analysis to quantify microRNA expression, after which miR-148a-3p was selected for further study. We performed CT scans of the knee on all subjects with SCI and analyzed these scans to quantify bone marrow adipose tissue volume. MiR-148a-3p was upregulated in subjects with acute SCI vs chronic SCI, as well as in acute SCI vs no SCI. Subjects with chronic SCI had greater levels of marrow adiposity in the distal femoral diaphysis compared to subjects with acute SCI. MiR-148a-3p levels were negatively associated with distal femoral diaphysis marrow adiposity. A multivariable model showed that miR-148a-3p and BMI explained 24% of variation in marrow adiposity. A literature search revealed that miR-148a-3p has multiple bone and fat metabolism related targets. Our findings suggest that miR-148a-3p is a mediator of osteoporosis following spinal cord injury and a potential future therapeutic target.

An instructive role for Interleukin-7 receptor α in the development of human B-cell precursor leukemia.

Kinase signaling fuels growth of B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Yet its role in leukemia initiation is unclear and has not been shown in primary human hematopoietic cells. We previously described activating mutations in interleukin-7 receptor alpha (IL7RA) in poor-prognosis "ph-like" BCP-ALL. Here we show that expression of activated mutant IL7RA in human CD34+ hematopoietic stem and progenitor cells induces a preleukemic state in transplanted immunodeficient NOD/LtSz-scid IL2Rγnull mice, characterized by persistence of self-renewing Pro-B cells with non-productive V(D)J gene rearrangements. Preleukemic CD34+CD10highCD19+ cells evolve into BCP-ALL with spontaneously acquired Cyclin Dependent Kinase Inhibitor 2 A (CDKN2A) deletions, as commonly observed in primary human BCP-ALL. CRISPR mediated gene silencing of CDKN2A in primary human CD34+ cells transduced with activated IL7RA results in robust development of BCP-ALLs in-vivo. Thus, we demonstrate that constitutive activation of IL7RA can initiate preleukemia in primary human hematopoietic progenitors and cooperates with CDKN2A silencing in progression into BCP-ALL.

3-Ketodihydrosphingosine reductase maintains ER homeostasis and unfolded protein response in leukemia.

Sphingolipids and their metabolic pathways have been implicated in disease development and therapeutic response; however, the detailed mechanisms remain unclear. Using a sphingolipid network focused CRISPR/Cas9 library screen, we identified an endoplasmic reticulum (ER) enzyme, 3-Ketodihydrosphingosine reductase (KDSR), to be essential for leukemia cell maintenance. Loss of KDSR led to apoptosis, cell cycle arrest, and aberrant ER structure. Transcriptomic analysis revealed the indispensable role of KDSR in maintaining the unfolded protein response (UPR) in ER. High-density CRISPR tiling scan and sphingolipid mass spectrometry pinpointed the critical role of KDSR's catalytic function in leukemia. Mechanistically, depletion of KDSR resulted in accumulated 3-ketodihydrosphingosine (KDS) and dysregulated UPR checkpoint proteins PERK, ATF6, and ATF4. Finally, our study revealed the synergism between KDSR suppression and pharmacologically induced ER-stress, underscoring a therapeutic potential of combinatorial targeting sphingolipid metabolism and ER homeostasis in leukemia treatment.

Factors Associated with Ocular Injury in Orbital Fracture Patients: Who Requires Urgent Ophthalmic Evaluation?

Importance: Create validated criteria to identify orbital fracture patients at higher risk for significant ocular injuries. Objective: Determine history and physical examination findings in orbital fracture patients who are associated with ocular injury and warrant urgent assessment by an ophthalmologist. Design, Setting, and Participants: Retrospective chart review of 535 adult orbital fracture patients evaluated at a Level I emergency department between 2014 and 2017, without prior history of orbital fracture, ocular injury, or ocular/orbital surgery. Main Outcomes and Measure: Presence of ocular injury. Results: In total, 195 (36%) patients had an ocular injury. Those with and without ocular injury were compared in a multivariate logistic regression model including demographics, fracture characteristics, injury mechanism, and physical examination findings. Visual acuity change, radiographic retrobulbar hemorrhage, abnormal pupillary reaction, and inability to open the injured eye all had significant associations with ocular injury when other findings were controlled. Conclusion: This study shows a significant association between ocular injury and visual acuity change, retrobulbar hemorrhage, abnormal pupillary reaction, and inability to open the injured eye. These factors can help triage when to obtain an urgent ophthalmology consult.

High-resolution characterization of gene function using single-cell CRISPR tiling screen.

Identification of novel functional domains and characterization of detailed regulatory mechanisms in cancer-driving genes is critical for advanced cancer therapy. To date, CRISPR gene editing has primarily been applied to defining the role of individual genes. Recently, high-density mutagenesis via CRISPR tiling of gene-coding exons has been demonstrated to identify functional regions in genes. Furthermore, breakthroughs in combining CRISPR library screens with single-cell droplet RNA sequencing (sc-RNAseq) platforms have revealed the capacity to monitor gene expression changes upon genetic perturbations at single-cell resolution. Here, we present "sc-Tiling," which integrates a CRISPR gene-tiling screen with single-cell transcriptomic and protein structural analyses. Distinct from other reported single-cell CRISPR screens focused on observing gene function and gene-to-gene/enhancer-to-gene regulation, sc-Tiling enables the capacity to identify regulatory mechanisms within a gene-coding region that dictate gene activity and therapeutic response.