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Myotonic dystrophy (DM1), the most common muscular dystrophy in adults, is caused by an expanded (CTG) n tract in the 3′ UTR of the gene encoding myotonic dystrophy protein kinase (DMPK) 1 , which results in nuclear entrapment of the 'toxic' mutant RNA and interacting RNAbinding proteins (such as MBNL1) in ribonuclear inclusions 2 . It is unclear if therapy aimed at eliminating the toxin would be beneficial. To address this, we generated transgenic mice expressing the DMPK 3′ UTR as part of an inducible RNA transcript encoding green fluorescent protein (GFP). We were surprised to find that mice overexpressing a normal DMPK 3′ UTR mRNA reproduced cardinal features of myotonic dystrophy, including myotonia, cardiac conduction abnormalities, histopathology and RNA splicing defects in the absence of detectable nuclear inclusions. However, we observed increased levels of CUG-binding protein (CUG-BP1) in skeletal muscle, as seen in individuals with DM1. Notably, these effects were reversible in both mature skeletal and cardiac muscles by silencing transgene expression. These results represent the first in vivo proof of principle for a therapeutic strategy for treatment of myotonic dystrophy by ablating or silencing expression of the toxic RNA molecules.Common features of adult-onset DM1 include myotonia, progressive skeletal muscle loss, cardiac conduction defects, smooth muscle dysfunction, cataracts and insulin resistance 2 . The normal number of CTG repeats (n = 5 to ~30) is higher (n = 50 to >3,000) in individuals with DM1 (ref. 1 ). Unlike the wild-type transcript, mutant DMPK mRNA forms nuclear aggregates 3,4 and is thought to trigger dominant effects by aberrant interactions with or altered activity of RNA splicing factors, principally members of the muscleblind-like (MBNL) family (such as MBNL1) and the CUG-BP and ETR3-like factor (CELF) family (such as CUG-BP1), leading to abnormal splicing of specific RNAs such as chloride channel (Clcn1), insulin Correspondence should be addressed to M.S.M. (mahadevan@virginia.edu). 4 These authors contributed equally to this work. AUTHOR CONTRIBUTIONSM.S.M., R.S.Y., Q.Y., C.D.F.-M., T.D.B. and L.H.P. performed experimental work and data analysis. S.B. generated the transgene constructs. M.S.M. was responsible for conceptual design and execution. COMPETING INTERESTS STATEMENTThe authors declare that they have no competing financial interests. One potential therapeutic approach in DM1 is to get rid of the toxic RNA from cells. However, it is unclear if this will alleviate the effects of the disease. We used the tetracycline (Tet) inducible system with the reverse tetracycline transactivator (rtTA) to generate double transgenic mice harboring (i) a Tet-responsive, DMPK promoter 10,11 -driven transgene (named GFP-DMPK 3′ UTR) expressing the DMPK 3′ UTR mRNA as part of a GFP transcript, and (ii) a constitutively expressed rtTA transgene (Fig. 1a) Fig. 1). Notably, RNA blots of skeletal muscle RNA showed two major species due to alternative use of polyadenylation signal...

Kidney failure is common in patients with Coronavirus Disease-19 (COVID-19) resulting in increased morbidity and mortality. In an international collaboration, 284 kidney biopsies were evaluated to improve understanding of kidney disease in COVID-19. Diagnoses were compared to five years of 63,575 native biopsies prior to the pandemic and 13,955 allograft biopsies to identify diseases increased in patients with COVID-19. Genotyping for APOL1 G1 and G2 alleles was performed in 107 African American and Hispanic patients. Immunohistochemistry for SARS-CoV-2 was utilized to assess direct viral infection in 273 cases along with clinical information at the time of biopsy. The leading indication for native biopsy was acute kidney injury (45.4%), followed by proteinuria with or without concurrent acute kidney injury (42.6%). There were more African American patients (44.6%) than patients of other ethnicities. The most common diagnosis in native biopsies was collapsing glomerulopathy (25.8%) which associated with high-risk APOL1 genotypes in 91.7% of cases. Compared to the five-year biopsy database, the frequency of myoglobin cast nephropathy and proliferative glomerulonephritis with monoclonal IgG deposits was also increased in patients with COVID-19 (3.3% and 1.7%, respectively), while there was a reduced frequency of chronic conditions (including diabetes mellitus, IgA nephropathy, and arterionephrosclerosis) as the primary diagnosis. In transplants, the leading indication was acute kidney injury (86.4%), for which rejection was the predominant diagnosis (61.4%). Direct SARS-CoV-2 viral infection was not identified. Thus, our multi-center large case series identified kidney diseases that disproportionately affect patients with COVID-19, demonstrated a high frequency of APOL1 high-risk genotypes within this group, with no evidence of direct viral infection within the kidney.

Low-grade infiltrating gliomas in adults include diffuse astrocytoma, oligoastrocytoma and oligodendroglioma. The current gold standard diagnosis of these tumors relies on histological classification; however, emerging molecular abnormalities discovered in these tumors are playing an increasingly prominent part in the process of tumor diagnosis and, consequently, patient management. The frequency and clinical importance of tumor protein p53 (TP53) abnormalities, deletions involving chromosomes 1p and 19q, O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation status, abnormalities in the PTEN tumor suppressor gene and the BRAF oncogene, and isocitrate dehydrogenase (IDH) mutations have become better defined. Molecular markers have not, historically, had an important role in determining the course of treatment for patients with low-grade gliomas, but ongoing phase III clinical trials incorporate 1p deletion or 1p19q codeletion status-and future trials plan to incorporate MGMT promoter methylation status-as stratification factors. Future trials will need to incorporate IDH mutational status in addition to these factors. Ultimately, molecular marker assessment will, hopefully, improve the accuracy of tumor diagnosis and enhance the effectiveness of treatment to achieve improved patient outcomes.

BackgroundDexamethasone (DXM) is commonly used in the management of cerebral edema in patients diagnosed with glioblastoma multiforme (GBM). Bevacizumab (BEV) is FDA-approved for the progression or recurrence of GBM but has not been shown to improve survival when given for newly diagnosed patients concurrently with radiation (RT) and temozolomide (TMZ). Both DXM and BEV reduce cerebral edema, however, DXM has been shown to induce cytokine cascades which could interfere with cytotoxic therapy. We investigated whether DXM would reduce survival of GBM patients in the setting of concurrent TMZ and BEV administration.MethodsWe reviewed the treatment of all 73 patients with GBM who received definitive therapy at our institution from 2005 to 2013 with RT (60 Gy) delivered with concurrent daily TMZ (75 mg/m2). Of these, 34 patients also were treated with concurrent BEV (10 mg/kg every two weeks). Patients received adjuvant therapy (TMZ or TMZ/Bev) until either progression, discontinuation due to toxicity, or 12 months after radiation completion. All patients who had GBM progression with TMZ were offered BEV for salvage therapy, with 19 (56 %) receiving BEV.ResultsWith a median follow-up of 15.6 months, 67 (91.8 %) patients were deceased. The OS for the entire cohort was 15.9 months, while the PFS was 7.7 months. The extent of resection was a prognostic indicator for OS (p = .0044). The median survival following gross tumor resection (GTR) was 22.5 months, subtotal resection (STR) was 14.9 months, and biopsy was 12.1 months. The addition of BEV to TMZ with RT was borderline significantly associated with increased PFS (9.4 vs. 5.1 months, p = 0.0574) although was not significantly associated with OS (18.1 vs. 15.3 months respectively, p = 0.3064). In patients receiving TMZ, DXM use concurrent with RT was a poor prognostic indicator of both OS (12.7 vs. 22.6 months, p = 0.003) and PFS (3.6 vs. 8.4 months, p <0.0001). DXM did not reduce OS in patients who received TMZ and BEV concurrently with RT (22.9 vs 22.8 months, p = 0.4818). On multivariable analysis, DXM use predicted an unfavorable OS hazard ratio (HR) = 1.72, p = 0.045).ConclusionsOur results with TMZ, BEV, and RT are similar to previous studies in terms of PFS and OS. DXM use during RT with concurrent TMZ correlated with reduced OS and PFS unless BEV was administered.

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Olfactory neuroblastoma (ONB) is a rare neoplasm of the head and neck region that is included in the differential diagnosis of other sinonasal tract malignancies. We studied the usefulness of using p63 as an aid in the diagnosis of ONB and other tumors of the sinonasal region. The specimens were 14 ONBs; 4 nasopharyngeal carcinomas (NPCs), nonkeratinizing subtype; 2 NPCs, undifferentiated subtype; 10 sinonasal undifferentiated carcinomas (SNUCs); 7 malignant melanomas; and 2 extranodal natural killer (NK)/T-cell lymphomas. We observed p63 expression in 5 ONBs (36%), 4 nonkeratinizing NPCs (100%), 1 undifferentiated NPC (50%), 2 SNUCs (20%); 0 malignant melanomas (0%); and 1 extranodal NK/T-cell lymphoma (50%). While all cases of NPC with positive staining for p63 showed strong and diffuse immunoreactivity, the ONB, SNUC, and lymphoma cases with positive immunoreactivity showed only focal staining for p63. No p63 expression was observed in malignant melanoma. We think p63 is a useful marker to help distinguish nonkeratinizing or undifferentiated NPC subtypes from various sinonasal tract malignancies. In particular, p63 helps distinguish nonkeratinizing and undifferentiated NPC subtypes from SNUC.

Background: Membranous lupus nephritis (MLN) comprises 10-15 percent of lupus nephritis and increases morbidity and mortality of patients with systemic lupus erythematosus (SLE) through complications of nephrotic syndrome and chronic kidney failure. Identification of the target antigens in MLN may enable non-invasive monitoring of disease activity, inform treatment decisions, and aid in prognostication, as is now possible for idiopathic MN caused by antibodies against the phospholipase A2 receptor. Here, we show evidence for type III transforming growth factor-beta receptor (TGFBR3) as a novel biomarker expressed in a subset of patients with membranous lupus nephritis. Methods: We utilized mass spectrometry for protein discovery through enrichment of glomerular proteins by laser capture microdissection and through elution of immune complexes within MLN biopsies. Co-localization with IgG within glomerular immune deposits from patients and disease controls was evaluated by confocal microscopy. Immunostaining of consecutive case series was used to determine the overall frequency in MN and MLN. Results: TGFBR3 was found to be enriched in glomeruli and co-immunoprecipitated with IgG within a subset of MLN biopsies by mass spectrometry. Staining of consecutive MN cases without clinical evidence of SLE did not show TGFBR3 expression (0/104), but showed a 5.5% prevalence in MLN (11/199 cases). TGFBR3 co-localized with IgG along the glomerular basement membranes in TGFBR3-associated MN, but not in control cases. Conclusions: Positive staining for TGFBR3 within glomerular immune deposits represents a distinct form of membranous nephropathy, substantially enriched in membranous lupus nephritis. A diagnosis of TGFBR3-associated MN can alert the clinician to search for an underlying autoimmune disease.