Structural architecture of TolQ-TolR inner membrane protein complex from opportunistic pathogen Acinetobacter baumannii.

Gram-negative bacteria harness the proton motive force (PMF) within their inner membrane (IM) to uphold the integrity of their cell envelope, an indispensable aspect for both division and survival. The IM TolQ-TolR complex is the essential part of the Tol-Pal system, serving as a conduit for PMF energy transfer to the outer membrane. Here we present cryo-EM reconstructions of Acinetobacter baumannii TolQ in apo and TolR- bound forms at atomic resolution. The apo TolQ configuration manifests as a symmetric pentameric pore, featuring a trans-membrane funnel leading towards a cytoplasmic chamber. In contrast, the TolQ-TolR complex assumes a proton non-permeable stance, characterized by the TolQ pentamer's flexure to accommodate the TolR dimer, where two protomers undergo a translation-based relationship. Our structure-guided analysis and simulations support the rotor-stator mechanism of action, wherein the rotation of the TolQ pentamer harmonizes with the TolR protomers' interplay. These findings broaden our mechanistic comprehension of molecular stator units empowering critical functions within the Gram-negative bacterial cell envelope. Teaser: Apo TolQ and TolQ-TolR structures depict structural rearrangements required for cell envelope organization in bacterial cell division.

The Pan-RAF-MEK Nondegrading Molecular Glue NST-628 Is a Potent and Brain-Penetrant Inhibitor of the RAS-MAPK Pathway with Activity across Diverse RAS- and RAF-Driven Cancers.

Alterations in the RAS-MAPK signaling cascade are common across multiple solid tumor types and are a driver for many cancers. NST-628 is a potent pan-RAF-MEK molecular glue that prevents the phosphorylation and activation of MEK by RAF, overcoming the limitations of traditional RAS-MAPK inhibitors and leading to deep durable inhibition of the pathway. Cellular, biochemical, and structural analyses of RAF-MEK complexes show that NST-628 engages all isoforms of RAF and prevents the formation of BRAF-CRAF heterodimers, a differentiated mechanism from all current RAF inhibitors. With a potent and durable inhibition of the RAF-MEK signaling complex as well as high intrinsic permeability into the brain, NST-628 demonstrates broad efficacy in cellular and patient-derived tumor models harboring diverse MAPK pathway alterations, including orthotopic intracranial models. Given its functional and pharmacokinetic mechanisms that are differentiated from previous therapies, NST-628 is positioned to make an impact clinically in areas of unmet patient need. Significance: This study introduces NST-628, a molecular glue having differentiated mechanism and drug-like properties. NST-628 treatment leads to broad efficacy with high tolerability and central nervous system activity across multiple RAS- and RAF-driven tumor models. NST-628 has the potential to provide transformative clinical benefits as both monotherapy and vertical combination anchor.

Successful treatment of stage IVB ovarian carcinosarcoma with PARP Inhibitor: A case report.

•Ovarian carcinosarcoma is a rare ovarian cancer histology that has limited treatment options.•In this study, we present an unusual association between carcinosarcoma and a STIC lesion.•In select patients with carcinosarcoma, PARP inhibition may provide clinical benefit.

Placenta Accreta Spectrum: Evaluation of classic and non-classic presentations, pathologic grading, and uterine scar dehiscence features in a modern institutional series.

INTRODUCTION: The aim of this study is to document the distribution of classic versus non-classic presentation of Placenta Accreta Spectrum (PAS) disorders as well as grading categories by the Society for Pediatric Pathology (SPP) and FIGO systems in an institutional cohort of gravid hysterectomies. We also document the prevalence of uterine scar as a histologic correlate for uterine scar dehiscence, a phenomenon raised by some as central to PAS pathogenesis. METHODS: PAS cases were assigned grade and designated as classic (anterior lower uterine segment implantation, prior C-section) or non-classic (implantation away from anterior lower uterine segment and/or no prior C-section). Features of dehiscence (uterine window, histologic evidence of scar) were recorded. RESULTS: Sixty-two patients were included: 76 % had prior C-section; 55 % had other forms of uterine instrumentation. Classic PAS was recorded in 52 % patients; notably, 48 % had non-classic presentation; of these, all but one had prior instrumentation (curettage, myomectomy, laparoscopy). Uterine window was described in 53 % classic and 23 % non-classic PAS. Scar was demonstrated in 31 % classic and 23 % non-classic PAS; trichrome/reticulin stains were confirmatory. 32 % cases were SPP grade 1, 18 % grade 2, 18 % grade 3a and 32 % grade 3d. Grade 3 was significantly more common in classic (72 %) than non-classic (27 %) PAS. DISCUSSION: While most PAS patients have classic presentation, a large subset does not; in addition, scar tissue is not identified histologically in most PAS hysterectomies; in these settings, PAS cannot be fully attributed to scar dehiscence. Uterine instrumentation often precedes non-classic PAS reinforcing the concept of decidual disruption as central to PAS pathogenesis. PAS grading as defined correlates with presentation (classic vs non-classic).

Outcome-Based Risk Stratification Model for the Diagnosis of Placental Maternal Vascular Malperfusion.

The Amsterdam Consensus Statement introduced the term maternal vascular malperfusion (MVM) to group a constellation of findings associated with impaired maternal-placental circulation. In isolation, these findings are relatively common in placentas from normal gestations, and there is uncertainty on how many, and which, are required. We aimed to determine the criteria essential for MVM diagnosis in correlation with obstetrical outcomes. A total of 200 placentas (100 with a reported diagnosis of MVM and 100 controls matched by maternal age and gravida-para-abortus status) were reviewed to document MVM features. Obstetrical outcomes in the current pregnancy were recorded including hypertension, pre-eclampsia with or without severe features, gestational diabetes, prematurity, fetal growth restriction, and intrauterine fetal demise. On univariate logistic regression analysis, adverse outcome was associated with low placental weight (LPW, <10% percentile for gestational age), accelerated villous maturation (AVM), decidual arteriopathy (DA), infarcts (presence and volume), distal villous hypoplasia, and excess multinucleated trophoblast in basal plate ≥2 mm (all P < .01) but not with retroplacental hemorrhage. In a multivariable model DA, infarcts and AVM were significantly associated with adverse outcomes, whereas LPW showed a trend toward significance. A receiver-operating characteristic curve including these 4 parameters showed good predictive ability (area under the curve [AUC], 0.8256). Based on the probability of an adverse outcome, we recommend consistent reporting of DA, AVM, infarcts, and LPW, summarizing them as "diagnostic of MVM" (DA or AVM plus any other feature, yielding a probability of 65%-97% for adverse obstetrical outcomes) or "suggestive of MVM" (if only 1 feature is present, or only 2 features are infarcts plus LPW, yielding a probability of up to 52%). Other features such as distal villous hypoplasia, excess (≥2 mm) multinucleated trophoblast, and retroplacental hemorrhage can also be reported, and their role in MVM diagnosis should be further studied.

A cryptic microdeletion del(12)(p11.21p11.23) within an unbalanced translocation t(7;12)(q21.13;q23.1) implicates new candidate loci for intellectual disability and Kallmann syndrome.

In a patient diagnosed with both Kallmann syndrome (KS) and intellectual disability (ID), who carried an apparently balanced translocation t(7;12)(q22;q24)dn, array comparative genomic hybridization (aCGH) disclosed a cryptic heterozygous 4.7 Mb deletion del(12)(p11.21p11.23), unrelated to the translocation breakpoint. This novel discovery prompted us to consider the possibility that the combination of KS and neurological disorder in this patient could be attributed to gene(s) within this specific deletion at 12p11.21-12p11.23, rather than disrupted or dysregulated genes at the translocation breakpoints. To further support this hypothesis, we expanded our study by screening five candidate genes at both breakpoints of the chromosomal translocation in a cohort of 48 KS patients. However, no mutations were found, thus reinforcing our supposition. In order to delve deeper into the characterization of the 12p11.21-12p11.23 region, we enlisted six additional patients with small copy number variations (CNVs) and analyzed eight individuals carrying small CNVs in this region from the DECIPHER database. Our investigation utilized a combination of complementary approaches. Firstly, we conducted a comprehensive phenotypic-genotypic comparison of reported CNV cases. Additionally, we reviewed knockout animal models that exhibit phenotypic similarities to human conditions. Moreover, we analyzed reported variants in candidate genes and explored their association with corresponding phenotypes. Lastly, we examined the interacting genes associated with these phenotypes to gain further insights. As a result, we identified a dozen candidate genes: TSPAN11 as a potential KS candidate gene, TM7SF3, STK38L, ARNTL2, ERGIC2, TMTC1, DENND5B, and ETFBKMT as candidate genes for the neurodevelopmental disorder, and INTS13, REP15, PPFIBP1, and FAR2 as candidate genes for KS with ID. Notably, the high-level expression pattern of these genes in relevant human tissues further supported their candidacy. Based on our findings, we propose that dosage alterations of these candidate genes may contribute to sexual and/or cognitive impairments observed in patients with KS and/or ID. However, the confirmation of their causal roles necessitates further identification of point mutations in these candidate genes through next-generation sequencing.

STK11 Adnexal Tumor in an Adolescent Female: Diagnostic Pitfalls of a Recently Described Entity.

STK11 adnexal tumor is a recently described entity with less than 25 cases reported to date. These aggressive tumors typically occur in paratubal/paraovarian soft tissues, have characteristically striking morphologic and immunohistochemical heterogeneity, and harbor pathognomonic alterations in STK11. These occur almost exclusively in adult patients, with only one reported in a pediatric patient (to our knowledge). A previously healthy 16-year-old female presented with acute abdominal pain. Imaging studies revealed large bilateral solid and cystic adnexal masses, ascites, and peritoneal nodules. Following frozen section evaluation of a left ovarian surface nodule, bilateral salpingo-oophorectomy and tumor debulking were performed. Histologically, the tumor demonstrated distinctively variable cytoarchitecture, myxoid stroma, and mixed immunophenotype. A next generation sequencing-based assay identified a pathogenic STK11 mutation. We report the youngest patient to date with an STK11 adnexal tumor, highlighting key clinicopathologic and molecular features in order to contrast them with those of other pediatric intra-abdominal malignancies. This rare and unfamiliar tumor poses a considerable diagnostic challenge and requires a multidisciplinary integrated approach to diagnosis.

Placental lesions attributed to shallow implantation, excess extravillous trophoblast and decidual hypoxia: Correlation with maternal vascular malperfusion and related obstetric conditions.

INTRODUCTION: Maternal vascular malperfusion (MVM) is one of four main patterns of placental injury defined by the Amsterdam consensus statement and is associated with adverse fetal and maternal outcomes. Laminar decidual necrosis (DLN), extravillous trophoblast islands (ETIs), placental septa (PS), and basal plate multinucleate implantation-type trophoblasts (MNTs) are lesions attributed to decidual hypoxia, excess trophoblast, and shallow implantation, but are not included in the current MVM diagnostic criteria. We aimed to investigate the relationship between these lesions and MVM. METHODS: A case-control model was used to evaluate for DLN, ETIs, PS, and MNTs. Placentas with MVM on pathologic examination (defined as ≥2 related lesions) constituted the case group, and maternal age- and GPA-status-matched placentas with less than 2 lesions constituted the control group. MVM-related obstetric morbidities were recorded, including hypertension, preeclampsia, and diabetes. These were correlated with the lesions of interest. RESULTS: 200 placentas were reviewed: 100 MVM cases and 100 controls. MNTs and PS showed significant enrichment in the MVM group (p < .05). Furthermore, larger foci of MNTs (>2 mm linear extent) were significantly associated with chronic or gestational hypertension (OR = 4.10; p < .05) and preeclampsia (OR = 8.14; p < .05). DLN extent correlated with placental infarction, but DLN and ETIs (including size and number) lacked association with MVM-related clinical conditions. DISCUSSION: As a marker of abnormally shallow placentation and related maternal morbidities, MNT merits inclusion within the MVM pathologic spectrum. Consistent reporting of MNTs >2 mm in size is recommended, as these lesions correlate with other MVM lesions and MVM-predisposing morbidities. Other lesions, particularly DLN and ETI, lacked such association questioning their diagnostic utility.

Structural insights into the assembly of the agrin/LRP4/MuSK signaling complex.

MuSK is a receptor tyrosine kinase (RTK) that plays essential roles in the formation and maintenance of the neuromuscular junction. Distinct from most members of RTK family, MuSK activation requires not only its cognate ligand agrin but also its coreceptors LRP4. However, how agrin and LRP4 coactivate MuSK remains unclear. Here, we report the cryo-EM structure of the extracellular ternary complex of agrin/LRP4/MuSK in a stoichiometry of 1:1:1. This structure reveals that arc-shaped LRP4 simultaneously recruits both agrin and MuSK to its central cavity, thereby promoting a direct interaction between agrin and MuSK. Our cryo-EM analyses therefore uncover the assembly mechanism of agrin/LRP4/MuSK signaling complex and reveal how MuSK receptor is activated by concurrent binding of agrin and LRP4.

Localized Endometrial Proliferations of Pregnancy are Clonal Glandular Outgrowths Characterized by PTEN Loss and PIK3CA Pathogenic Variants.

Gestational endometrium can demonstrate a spectrum of atypical but benign changes. One such lesion is localized endometrial proliferation of pregnancy (LEPP), first described in a series of 11 cases. To understand its biological and clinical importance, we explore the pathologic, immunophenotypic, and molecular features of this entity. Nine cases of LEPP identified in 15 years were retrieved from departmental archives and reviewed. Immunohistochemistry and next-generation sequencing using a comprehensive 446-gene panel were performed when the material was available. Eight cases were identified in curettage specimens performed after first-trimester pregnancy loss, and 1 in the basal plate of a mature placenta. The mean patient age was 35 (range 27-41) years. The mean lesion size was 6.3 (range 2-12) mm. Architectural patterns, often coexisting in the same case, included cribriform (n = 7), solid (n = 5), villoglandular (n = 2), papillary (n = 2), and micropapillary (n = 1). Cytologic atypia was mild in 7 cases and moderate in 2. Mitotic activity was low (up to 3 per 2.4 mm2). All lesions were associated with neutrophils. Background Arias-Stella phenomenon was present in 4 cases. Immunohistochemistry was performed in 7 LEPP, all of which demonstrated wildtype p53, retained MSH6 and PMS2, membranous beta-catenin, and positive estrogen receptor (mean 71%) and progesterone receptor (mean 74%). All were negative for p40 except 1 case (focal weak positivity). PTEN was markedly reduced in background secretory glands in all cases; in 5/7, LEPP foci showed a complete absence of PTEN expression. PIK3CA pathogenic variants were identified in 4/4 cases sequenced; 3/4 had inactivating PTEN mutations. Follow-up, available in 8 patients (mean length = 51 months, range 7-161), was conservative with observation only and showed no persistence or adverse outcomes. LEPP is characterized by intraglandular cribriform/solid architecture, positive estrogen receptor/progesterone receptor, PTEN loss, and PIK3CA and PTEN mutations. Although our findings indicate that LEPP is neoplastic, for now, we advise against diagnosing LEPP as endometrial carcinoma or hyperplasia because LEPP has a particular clinicopathologic context (concurrent gestation), distinct morphology (purely intraepithelial complex growth), and indolent outcome. Thus, it should be distinguished from endometrial intraepithelial neoplasia and carcinoma for which therapeutic interventions are indicated.

A microdeletion del(12)(p11.21p11.23) with a cryptic unbalanced translocation t(7;12)(q21.13;q23.1) implicates new candidate loci for intellectual disability and Kallmann syndrome.

In an apparently balanced translocation t(7;12)(q22;q24)dn exhibiting both Kallmann syndrome (KS) and intellectual disability (ID), we detected a cryptic heterozygous 4.7 Mb del(12)(p11.21p11.23) unrelated to the translocation breakpoint. This new finding raised the possibility that KS combined with neurological disorder in this patient could be caused by gene(s) within this deletion at 12p11.21-12p11.23 instead of disrupted or dysregulated genes at the genomic breakpoints. Screening of five candidate genes at both breakpoints in 48 KS patients we recruited found no mutation, corroborating our supposition. To substantiate this hypothesis further, we recruited six additional subjects with small CNVs and analyzed eight individuals carrying small CNVs in this region from DECIPHER to dissect 12p11.21-12p11.23. We used multiple complementary approaches including a phenotypic-genotypic comparison of reported cases, a review of knockout animal models recapitulating the human phenotypes, and analyses of reported variants in the interacting genes with corresponding phenotypes. The results identified one potential KS candidate gene ( TSPAN11 ), seven candidate genes for the neurodevelopmental disorder ( TM7SF3 , STK38L , ARNTL2 , ERGIC2 , TMTC1 , DENND5B , and ETFBKMT ), and four candidate genes for KS with ID ( INTS13 , REP15 , PPFIBP1 , and FAR2 ). The high-level expression pattern in the relevant human tissues further suggested the candidacy of these genes. We propose that the dosage alterations of the candidate genes may contribute to sexual and/or cognitive impairment in patients with KS and/or ID. Further identification of point mutations through next generation sequencing will be necessary to confirm their causal roles.

Fumarate Hydratase and S-(2-Succinyl)-Cysteine Immunohistochemistry Shows Evidence of Fumarate Hydratase Deficiency in 2% of Uterine Leiomyosarcomas: A Cohort Study of 348 Tumors.

Approximately 1% to 1.5% of uterine leiomyomas are fumarate hydratase (FH)-deficient (FHd). A subset of these are associated with germline FH mutations. However, the prevalence and clinicopathologic characteristics of FHd uterine leiomyosarcoma (uLMS) remain unknown. Clinicopathologic data were collected for 348 uLMS. Morphologic features associated with FH deficiency (staghorn-type vessels, alveolar-pattern edema, macronucleoli with perinucleolar clearing, eosinophilic cytoplasmic inclusions, and chain-like nuclear arrangement) were documented. All 348 tumors were studied by FH immunohistochemistry. Eighty-nine were also studied by S-(2-succinyl)-cysteine (2SC) immunohistochemistry. Seven (2%) FHd uLMS were identified. Five showed uniformly negative FH and diffusely positive 2SC immunostaining; 1 showed variably negative to weak to strong FH and diffusely positive 2SC immunostaining; and 1 showed retained FH staining alongside positive 2SC confined to a morphologically distinct subclone. Three of 7 patients had extrauterine disease at presentation, and 3 of 6 had persistent disease or died from disease. Macronucleoli with perinucleolar clearing were significantly more common in FHd uLMS (7/7) than in uLMS with retained FH (182/341; P =0.017). Disease-specific survival, disease-free survival, and other morphologic features of FH deficiency did not differ significantly between FHd and FH-retained tumors. Our data emphasize that immunohistochemical FH deficiency does not preclude malignancy in uterine smooth muscle tumors. However, the biological significance and molecular basis of FH deficiency in uLMS, including any relationship to germline FH mutation, remain unknown, and a larger multi-institutional effort is necessary to gather sufficient FHd uLMS for more robustly powered clinicopathologic and for molecular characterization.

Dedifferentiated leiomyosarcoma of the uterus: a clinicopathologic and immunohistochemical analysis of 23 cases.

AIMS: To morphologically and immunophenotypically characterize dedifferentiated uterine leiomyosarcoma (LMS). METHODS AND RESULTS: We identified 23 dedifferentiated uterine LMS, defined as a malignant uterine smooth muscle tumour containing discrete differentiated and dedifferentiated components (i.e. with and without morphologic and immunophenotypic evidence of smooth muscle differentiation, respectively). The differentiated component was leiomyosarcoma in most cases (17/23), though some arose from a leiomyoma (n = 4) or smooth muscle tumour of uncertain malignant potential (n = 2). The dedifferentiated tumour component showed noncohesive polygonal cells with moderate to abundant cytoplasm, pleomorphic nuclei with coarse vesicular to smudged chromatin, one or more macronucleoli, frequent multinucleation, and atypical mitoses. Three cases showed heterologous osteosarcomatous or chondrosarcomatous differentiation. Immunohistochemistry revealed alterations characteristic of uterine LMS, including Rb loss (18/19); strong diffuse p16 (17/19); strong diffuse (9/19) or complete absence of (5/19) p53; and ATRX loss (6/16). Compared to a control cohort of uterine LMS without dedifferentiation, dedifferentiated uterine LMS showed significantly shorter disease-specific (median, 54 versus 20 months; 5-year DSS, 46% versus 36%; P = 0.04) and disease-free (median, 31 versus 8 months; 5-year DFS, 42% versus 8%; P = 0.002) survival. Of 19 dedifferentiated uterine LMS with follow-up, 12 had died of disease at median 14 (range, 2-73) months; four were alive with disease at 4, 12, 44, and 50 months; and three were alive with no evidence of disease at 56, 109, and 114 months. CONCLUSION: Routine prospective recognition of dedifferentiated uterine LMS and distinction from mimics is advocated for accurate prognostication and for further characterisation of these tumours.

Molecular analysis and essentiality of Aro1 shikimate biosynthesis multi-enzyme in Candida albicans.

In the human fungal pathogen Candida albicans, ARO1 encodes an essential multi-enzyme that catalyses consecutive steps in the shikimate pathway for biosynthesis of chorismate, a precursor to folate and the aromatic amino acids. We obtained the first molecular image of C. albicans Aro1 that reveals the architecture of all five enzymatic domains and their arrangement in the context of the full-length protein. Aro1 forms a flexible dimer allowing relative autonomy of enzymatic function of the individual domains. Our activity and in cellulo data suggest that only four of Aro1's enzymatic domains are functional and essential for viability of C. albicans, whereas the 3-dehydroquinate dehydratase (DHQase) domain is inactive because of active site substitutions. We further demonstrate that in C. albicans, the type II DHQase Dqd1 can compensate for the inactive DHQase domain of Aro1, suggesting an unrecognized essential role for this enzyme in shikimate biosynthesis. In contrast, in Candida glabrata and Candida parapsilosis, which do not encode a Dqd1 homolog, Aro1 DHQase domains are enzymatically active, highlighting diversity across Candida species.

Absence of SARS-CoV-2 Spike glycoprotein expression in placentas from individuals after mRNA SARS-CoV-2 vaccination.

Current public health initiatives to contain the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) global pandemic focus on expanding vaccination efforts to include vulnerable populations such as pregnant people. Vaccines using messenger ribonucleic acid (mRNA) technology rely on translation by immune cells, primarily at the injection site. Hesitancy remains among the general population regarding the safety of mRNA vaccines during gestation, and it remains unknown whether the SARS-CoV-2 Spike protein (the product of mRNA vaccines available) accumulates in the placenta after vaccination. Objective: To determine whether Spike protein translation and accumulation occurs in placental tissue in the context of recent mRNA SARC-CoV-2 vaccination during pregnancy. We identified 48 patients receiving one or two doses of mRNA SARS-CoV-2 vaccine during gestation and used immunohistochemistry against SARS-CoV-2 Spike protein in formalin-fixed, paraffin-embedded placental tissue. One placenta, positive for SARS-CoV-2 RNA by in situ hybridization (ISH) was used as positive control. Seven term placentas collected prior to the emergence of SARS-CoV-2 served as negative controls. Eighty one percent of patients in the study group underwent third-trimester delivery; remaining had a first-trimester spontaneous abortion or elective second-trimester termination. Patients received two (52%) or one (48%) vaccine doses during pregnancy, with a median interval between latest dose and delivery of 13 days (range 2-79 days). Most (63%) cases had their latest dose within 15 days prior to delivery. All the placentas in the study and negative control groups were negative for SARS-CoV-2 immunohistochemistry. Six study cases with short vaccine-delivery intervals (2-7 days) were subjected to SARS-CoV-2 ISH and were negative. Our findings suggest that mRNA vaccines do not reach significant concentrations in the placenta given the absence of definitive SARS-CoV-2 Spike protein accumulation in placental tissue. This observation provides evidence supporting the safety of mRNA vaccines to the placental-fetal unit.

A novel morphology-based risk stratification model for stage I uterine leiomyosarcoma: an analysis of 203 cases.

Uterine leiomyosarcoma is the most common uterine mesenchymal malignancy. The majority present at stage I, and clinical outcomes vary widely. However, no widely accepted risk stratification system for stage I uterine leiomyosarcoma is currently available. We studied 17 routinely evaluated clinicopathologic parameters in 203 stage I uterine leiomyosarcoma from three institutions to generate a novel risk stratification model for these tumors. Mitoses >25 per 2.4 mm2 (10 high-power fields), atypical mitoses, coagulative necrosis, lymphovascular invasion, and serosal abutment were significantly associated with disease-free and disease-specific survival in univariate and multivariate analyses. These prognostic parameters were each scored as binary ("yes" or "no") variables and fitted to a single optimized algebraic risk model:Risk score = (coagulative necrosis)(1) + (mitoses > 25 per 2.4 mm2)(2) + (atypical mitoses)(2) + (lymphovascular invasion)(3) + (serosal abutment)(5)By logistic regression, the risk model was significantly associated with 5-year disease-free (AUC = 0.9270) and 5-year disease-specific survival (AUC = 0.8517). Internal and external validation substantiated the model. The continuous score (range, 0-13) was optimally divided into 3 risk groups with distinct 5-year disease-free and disease-specific survival: low risk (0-2 points), intermediate risk (3-5 points), and high risk (6-13 points) groups. Our novel risk model performed significantly better than alternative uterine leiomyosarcoma risk stratification systems in predicting 5-year disease-free and disease-specific survival in stage I tumors. A simplified risk model, omitting terms for serosal abutment and lymphovascular invasion, can be accurately applied to myomectomy or morcellated specimens. We advocate routine application of this novel risk model in stage I uterine leiomyosarcoma to facilitate patient counseling and proper risk stratification for clinical trials.

Epithelioid Leiomyosarcoma of the Uterus: Modern Outcome-based Appraisal of Diagnostic Criteria in a Large Institutional Series.

Epithelioid leiomyosarcoma of the uterus is rare and poorly understood. Herein, we characterize a large institutional series of epithelioid leiomyosarcomas aiming to define outcome-determinant diagnostic pathologic features. We also retrieved epithelioid smooth muscle tumors of unknown malignant potential and evaluated a consecutive cohort of leiomyomas for epithelioid subtypes. Of a total of 1177 uterine leiomyosarcomas, 81 (7%) were categorized as epithelioid after review. Epithelioid leiomyosarcoma was strictly defined as having round to polygonal cells with visible pink cytoplasm and round to ovoid nuclei in ≥50% of the tumor volume. Average age was 55 years (range: 26 to 81 y). Median tumor size was 11 cm; tumor was >5 cm in 93% of subjects; 47% were stage 1 at presentation. An infiltrative tumor border was observed, grossly and/or microscopically, in 89% of cases; necrosis was noted in 80%, and vascular invasion in 47%. Mitotic count in 2.4 mm2 (totalling 10 high-power fields, each field 0.55 mm in diameter) ranged from 3 to 100 (median: 26). All cases had moderate, severe or highly pleomorphic atypia. All cases had 2 or 3 of the following: necrosis, at least moderate atypia and ≥4 mitoses in 2.4 mm2. Immunohistochemistry revealed frequent expression of smooth muscle markers including SMA (96%), desmin (95%), and caldesmon (81%). HMB45 and Melan-A were negative in 92% and 100% of cases, respectively. Estrogen and progesterone receptors were expressed by 65% and 54% of tumors, respectively. Follow-up information was available in 68 subjects (median: 23 mo, range: 1 to 254); cancer-related death occurred in 63%, and an additional 15% had recurrent or metastatic disease at last follow-up. Disease-specific survival was shorter in epithelioid leiomyosarcoma patients (median: 44 mo; 35% at 5-y) than in a matched cohort of nonepithelioid leiomyosarcoma (median: 55 mo; 46% at 5-y) (P=0.03). Three epithelioid smooth muscle tumors of unknown malignant potential were evaluated, all <5 cm in size and with atypia and/or irregular borders but mitotic count below the threshold for malignancy. Two of these had follow-up available, which was uneventful. Of 142 consecutive leiomyomas assessed, none had epithelioid morphology as defined. Epithelioid leiomyosarcoma is an aggressive neoplasm, sometimes with a remarkably low mitotic count. In the setting of an epithelioid smooth muscle tumor of the uterus, we postulate that the diagnosis of malignancy is made in the presence of ≥2 of the following: moderate or severe atypia, ≥4 mitoses/2.4 mm2 and tumor cell necrosis. In their absence, the finding of tumor size ≥5 cm, vascular invasion, infiltrative edges or atypical mitoses should be treated with caution, and designation as of at least uncertain malignant potential is warranted.

Well-developed Cerebellum in an Ovarian Mature Teratoma From a Pregnant Female.

Teratomas are the most common neoplasm of the ovary, comprising over half of all diagnosed tumors in patients under 50. Most lesions are classified as benign mature teratomas and are histologically defined by the presence of mature tissues from one or more of the embryological germ layers: ectoderm, mesoderm, and endoderm. Neuroectodermal derivatives, including glia, neurons, ependymal cells, and meninges are present in a third to half of mature teratomas. Although teratomatous tissue elements are typically arranged in a haphazard fashion, well-developed and organized embryonic organ structures have been rarely reported and often with limited histologic, clinical, or gross characterization. In this report, we describe the case of an ovarian mature cystic teratoma identified in a pregnant female which exhibited remarkably well-developed posterior fossa structures including lobated and foliated cerebellum with appropriate anatomic organization and associated brainstem, ventricular, and meningeal structures.

Placental Findings in Pregnancies Complicated by Maternal Cardiovascular Disease.

Background: The incidence of pregnancy in women with cardiovascular disease (CVD) has increased, yet little is known about placental pathology in these women. Objectives: The objectives of this study were to describe placental pathology in pregnancies complicated by maternal CVD and to compare findings among categories of maternal CVD. Methods: A retrospective, single-center study was conducted. Pathology reports for 264 placentas from pregnancies complicated by maternal CVD were reviewed for prespecified pathologic findings which were then compared against maternal characteristics. Results: Placentas were from pregnancies associated with maternal congenital heart disease (n = 171), arrhythmia (n = 43), cardiomyopathy (n = 20), connective tissue disease (n = 20), and valvular heart disease (n = 10). Median maternal age at delivery was 32 years (range: 19-49). Median gestational age at delivery was 39 weeks (range: 25-41). Placental pathology was identified in 75% (199/264) of placentas. Anatomic pathology, primarily small placenta by weight, was present in 45% (119/264) of placentas. Vascular pathology, primarily maternal vascular malperfusion or fetal vascular malperfusion, was seen in 41% (107/264) of placentas. Acute chorioamnionitis and villitis of unknown etiology (VUE) were seen in 23% (61/264) and 11% (28/264) of placentas, respectively. Prevalence of VUE differed across CVD categories (P = 0.008) and was most common in maternal congenital heart disease; there were no differences in anatomic, infectious, and vascular pathologies across CVD categories. Conclusions: Pregnancies among women with CVD commonly demonstrate abnormal placental findings, especially anatomic and vascular pathology. Prevalence of VUE differed across CVD categories. Otherwise, the incidence of specific pathology findings did not differ based on maternal characteristics.

Control of neurotransmitter release by two distinct membrane-binding faces of the Munc13-1 C1C2B region.

Munc13-1 plays a central role in neurotransmitter release through its conserved C-terminal region, which includes a diacyglycerol (DAG)-binding C1 domain, a Ca2+/PIP2-binding C2B domain, a MUN domain and a C2C domain. Munc13-1 was proposed to bridge synaptic vesicles to the plasma membrane through distinct interactions of the C1C2B region with the plasma membrane: (i) one involving a polybasic face that is expected to yield a perpendicular orientation of Munc13-1 and hinder release; and (ii) another involving the DAG-Ca2+-PIP2-binding face that is predicted to result in a slanted orientation and facilitate release. Here, we have tested this model and investigated the role of the C1C2B region in neurotransmitter release. We find that K603E or R769E point mutations in the polybasic face severely impair Ca2+-independent liposome bridging and fusion in in vitro reconstitution assays, and synaptic vesicle priming in primary murine hippocampal cultures. A K720E mutation in the polybasic face and a K706E mutation in the C2B domain Ca2+-binding loops have milder effects in reconstitution assays and do not affect vesicle priming, but enhance or impair Ca2+-evoked release, respectively. The phenotypes caused by combining these mutations are dominated by the K603E and R769E mutations. Our results show that the C1-C2B region of Munc13-1 plays a central role in vesicle priming and support the notion that two distinct faces of this region control neurotransmitter release and short-term presynaptic plasticity.