Citations

Background: Quadriceps tendon rupture following total knee arthroplasty (TKA) is an infrequent but potentially devastating adverse event. Although uncommon, the long-term sequelae of this injury can result in permanent inability to walk. Despite the severity of this injury, there is no single accepted treatment, with various surgical methods producing mixed results. Therefore, the purpose of this study was to assess the efficacy of a modified V-Y turndown flap as a viable alternative method of treatment for this injury. Methods: Twenty-four quadriceps tendon ruptures in 23 patients (10 men and 13 women) who underwent TKA (8 primary and 15 revision), including 1 tendon rerupture, were treated with use of a modified V-Y turndown. The average patient age at the time of the V-Y flap repair was 61 years (range, 41 to 86 years). Knee Society scores, range of motion, strength, medical comorbidities, nature of the procedure (i.e., primary versus revision), and the ability to walk were all recorded before and after the quadriceps reconstruction, along with general satisfaction and adverse events following the procedure. Results: Twelve patients (52%) had predisposing comorbidities, including obesity, diabetes, chronic dialysis, and steroid dependence. Prior to repair with the V-Y flap, none of the patients were able to walk independently, requiring either a wheelchair or walker. No patient had quadriceps strength greater than 3 (of 5), although all had full passive extension. Following the repair procedure, patients had significant (p < 0.0001) improvements in mean Knee Society knee score (88.7; range, 45 to 95) and mean strength (4.8; range, 3 to 5), and all were able to walk without assistive devices. Twenty knees exhibited active range of motion of 0° to 120°, whereas 4 had residual extensor lag of ≥5° (range, 5° to 35°). Major adverse events were limited to a single hematoma and an unacceptable extensor lag (35°) after repair. Conclusions: The modified V-Y quadriceps tendon turndown flap was a reliable alternative treatment for achieving restoration of the extensor mechanism after complete quadriceps tendon rupture following TKA. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Abstract A limited number of drugs are available to treat patients with polycythemia vera (PV) and essential thrombocythemia (ET). We attempted to identify alternative agents that may target abnormalities within malignant hematopoietic stem (HSCs) and progenitor cells (HPCs). Previously, MDM2 protein levels were shown to be upregulated in PV/ET CD34+ cells, and exposure to a nutlin, an MDM2 antagonist, induced activation of the TP53 pathway and selective depletion of PV HPCs/HSCs. This anticlonal activity was mediated by upregulation of p53 and potentiated by the addition of interferon-α2a (IFN-α2a). Therefore, we performed an investigator-initiated phase 1 trial of the oral MDM2 antagonist idasanutlin (RG7388; Roche) in patients with high-risk PV/ET for whom at least 1 prior therapy had failed. Patients not attaining at least a partial response by European LeukemiaNet criteria after 6 cycles were then allowed to receive combination therapy with low-dose pegylated IFN-α2a. Thirteen patients with JAK2 V617F+ PV/ET were enrolled, and 12 (PV, n = 11; ET, n = 1) were treated with idasanutlin at 100 and 150 mg daily, respectively, for 5 consecutive days of a 28-day cycle. Idasanutlin was well tolerated; no dose-limiting toxicity was observed, but low-grade gastrointestinal toxicity was common. Overall response rate after 6 cycles was 58% (7 of 12) with idasanutlin monotherapy and 50% (2 of 4) with combination therapy. Median duration of response was 16.8 months (range, 3.5-26.7). Hematologic, symptomatic, pathologic, and molecular responses were observed. These data indicate that idasanutlin is a promising novel agent for PV; it is currently being evaluated in a global phase 2 trial. This trial was registered at www.clinicaltrials.gov as #NCT02407080.

Marrow adipocytes reprogrammed by myeloma cells induce bone lesions.

PURPOSEDrug development is becoming increasingly expensive and time consuming. Drug repurposing is one potential solution to accelerate drug discovery. However, limited research exists on the use of electronic health record (EHR) data for drug repurposing, and most published studies have been conducted in a hypothesis-driven manner that requires a predefined hypothesis about drugs and new indications. Whether EHRs can be used to detect drug repurposing signals is not clear. We want to demonstrate the feasibility of mining large, longitudinal EHRs for drug repurposing by detecting candidate noncancer drugs that can potentially be used for the treatment of cancer.PATIENTS AND METHODSBy linking cancer registry data to EHRs, we identified 43,310 patients with cancer treated at Vanderbilt University Medical Center (VUMC) and 98,366 treated at the Mayo Clinic. We assessed the effect of 146 noncancer drugs on cancer survival using VUMC EHR data and sought to replicate significant associations (false discovery rate < .1) using the identical approach with Mayo Clinic EHR data. To evaluate replicated signals further, we reviewed the biomedical literature and clinical trials on cancers for corroborating evidence.RESULTSWe identified 22 drugs from six drug classes (statins, proton pump inhibitors, angiotensin-converting enzyme inhibitors, β-blockers, nonsteroidal anti-inflammatory drugs, and α-1 blockers) associated with improved overall cancer survival (false discovery rate < .1) from VUMC; nine of the 22 drug associations were replicated at the Mayo Clinic. Literature and cancer clinical trial evaluations also showed very strong evidence to support the repurposing signals from EHRs.CONCLUSIONMining of EHRs for drug exposure–mediated survival signals is feasible and identifies potential candidates for antineoplastic repurposing. This study sets up a new model of mining EHRs for drug repurposing signals.

Neutrophils are vital for antimicrobial defense; however, their role during viral infection is less clear. Furthermore, the molecular regulation of neutrophil fate and function at the viral infected sites is largely elusive. Here we report that BCL6 deficiency in myeloid cells exhibited drastically enhanced host resistance to severe influenza A virus (IAV) infection. In contrast to the notion that BCL6 functions to suppress innate inflammation, we find that myeloid BCL6 deficiency diminished lung inflammation without affecting viral loads. Using a series of Cre-transgenic, reporter, and knockout mouse lines, we demonstrate that BCL6 deficiency in neutrophils, but not in monocytes or lung macrophages, attenuated host inflammation and morbidity following IAV infection. Mechanistically, BCL6 bound to the neutrophil gene loci involved in cellular apoptosis in cells specifically at the site of infection. As such, BCL6 disruption resulted in increased expression of apoptotic genes in neutrophils in the respiratory tract, but not in the circulation or bone marrow. Consequently, BCL6 deficiency promoted tissue neutrophil apoptosis. Partial neutrophil depletion led to diminished pulmonary inflammation and decreased host morbidity. Our results reveal a previously unappreciated role of BCL6 in modulating neutrophil apoptosis at the site of infection for the regulation of host disease development following viral infection. Furthermore, our studies indicate that tissue-specific regulation of neutrophil survival modulates host inflammation and tissue immunopathology during acute respiratory viral infection.

1030 Background: Previous studies have shown that 44-71% of trastuzumab (T)-treated pts develop HER2-specific immunity (Clin Cancer Res 2007, 13:5133; Cancer Res 2016, 76:3702; Breast Cancer Res 2018, 20:52). M is an Fc-engineered mAb that shares similar HER2 binding and antiproliferative activity as T. The Fc region of M has been engineered for increased affinity to the activating FcγRIIIA (CD16A) and lower binding to the inhibitory FcγRIIB (CD32B), attributes that may enhance the mAb’s immune function, such as antigen presentation. Methods: HER2+ cancer pts who progressed on prior therapy received M (0.1-6 mg/kg QW for 3 of every 4 weeks [N = 34]; or 10-18 mg/kg Q3W [N = 32]) in phase 1 trial NCT01148849. PBMC and plasma were collected pre-dose and 50 days post-dose for 46 pts and > 4 years for 3 pts on long-term treatment. Response to HER2 or control antigens (Ag) was assessed by IFNγ ELISpot and antibody (Ab) ELISA. In 14 pts, T-cell antigen receptor (TCR) repertoire was assessed by immunosequencing. Results: Following M treatment, mean frequencies of IFNγ-producing T cells specific for intra- or extracellular fragments of HER2 increased by 2.5 to 6-fold (p < 0.0027, paired t test). Most (95%) of subjects responded to ≥2 of 6 (median = 5) HER2 Ag. Mean HER2-specific Ab concentration increased by 19-54% (p < 0.0001), with all subjects responding to ≥2 (median = 5) of the 6 Ag. A small 1.6-fold increase in IFNγ response to control CMV/EBV/Flu (but not tetanus or cyclin D1) peptides was observed; no increase in Ab response to control Ag was noted. Subsets of HER2-specific T-cell and Ab responses persisted during long-term treatment. Median TCR clonality increased by 54% (p = 0.003), with an average of 125 unique clones expanding, while overall TCR diversity remained unchanged (p = 0.19). Conclusions: Treatment of HER2+ cancer with M was associated with enhanced HER2-specific T-cell and Ab responses together with increased TCR clonality, indicative of a more focused T-cell repertoire. The high frequency of HER2-specific immunity in M-treated patients ( > 95%) is consistent with its enhanced Fc region contributing to linkage of innate and adaptive immune responses.

Abstract Understanding the molecular profile of every human cell type is essential for understanding its role in normal physiology and disease. Technological advancements in DNA sequencing, mass spectrometry, and computational methods allow us to carry out multiomics analyses although such approaches are not routine yet. Human umbilical vein endothelial cells (HUVECs) are a widely used model system to study pathological and physiological processes associated with the cardiovascular system. In this study, next‐generation sequencing and high‐resolution mass spectrometry to profile the transcriptome and proteome of primary HUVECs is employed. Analysis of 145 million paired‐end reads from next‐generation sequencing confirmed expression of 12 186 protein‐coding genes (FPKM ≥0.1), 439 novel long non‐coding RNAs, and revealed 6089 novel isoforms that were not annotated in GENCODE. Proteomics analysis identifies 6477 proteins including confirmation of N ‐termini for 1091 proteins, isoforms for 149 proteins, and 1034 phosphosites. A database search to specifically identify other post‐translational modifications provide evidence for a number of modification sites on 117 proteins which include ubiquitylation, lysine acetylation, and mono‐, di‐ and tri‐methylation events. Evidence for 11 “missing proteins,” which are proteins for which there was insufficient or no protein level evidence, is provided. Peptides supporting missing protein and novel events are validated by comparison of MS/MS fragmentation patterns with synthetic peptides. Finally, 245 variant peptides derived from 207 expressed proteins in addition to alternate translational start sites for seven proteins and evidence for novel proteoforms for five proteins resulting from alternative splicing are identified. Overall, it is believed that the integrated approach employed in this study is widely applicable to study any primary cell type for deeper molecular characterization.

BackgroundThe diagnosis of T‐cell neoplasms is often challenging, due to overlapping features with reactive T‐cells and limitations of currently available T‐cell clonality assays. The description of an antibody specific for one of two mutually exclusive T‐cell receptor (TCR) β‐chain constant regions (TRBC1) provide an opportunity to facilitate the detection of clonal TCRαβ T‐cells based on TRBC‐restriction.MethodsTwenty patients with mature T‐cell neoplasms and 44 patients without evidence of T‐cell neoplasia were studied. Peripheral blood (51), bone marrow (10), and lymph node (3) specimens were evaluated by 9‐color flow cytometry including TRBC1 (CD2/CD3/CD4/CD5/CD7/CD8/CD45/TCRγδ/TRBC1 and/or CD2/CD3/CD4/CD5/CD7/CD8/CD26/CD45/TRBC1). Monophasic TRBC1 expression on any immunophenotypically distinct CD4‐positive or CD8‐positive/TCRγδ‐negative T‐cell subset was considered indicative of clonality.ResultsMonophasic (clonal) TRBC1 expression was identified on immunophenotypically abnormal T‐cells from all 20 patients with T‐cell malignancies (100% sensitivity), including 17 cases with either >97% or <3% TRBC1‐positive events, and three cases with monophasic homogenous TRBC1‐dim expression. All immunophenotypically distinct CD4‐positive and CD8‐positive/TCRγδ‐negative T‐cell subsets from 44 patients without T‐cell malignancies showed the expected mixture of TRBC1‐positive and TRBC‐1‐negative subpopulations (non‐clonal), except for seven patients (16%) with very small CD8‐positive T‐cell subsets exhibiting a monophasic (clonal) pattern.ConclusionInclusion of a single anti‐TRBC1 antibody into a diagnostic T‐cell flow cytometry panel facilitates the rapid identification of T‐cell neoplasms, in addition to small monotypic CD8‐positive subsets of uncertain significance. © 2019 International Clinical Cytometry Society