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2.
J Drugs Dermatol ; 21(4): 425-426, 2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35389596

ABSTRACT

Becker nevus (BN) is a benign cutaneous smooth muscle hamartoma that presents with a hyperpigmented patch or plaque with or without hypertrichosis.1 BN may be associated with ipsilateral breast hypoplasia or other musculoskeletal abnormalities, an association which has been termed Becker nevus syndrome (BNS).


Subject(s)
Hyperpigmentation , Nevus , Skin Neoplasms , Breast/abnormalities , Humans , Hyperpigmentation/diagnosis , Hyperpigmentation/drug therapy , Nevus/complications , Nevus/diagnosis , Nevus/drug therapy , Skin Neoplasms/complications , Skin Neoplasms/diagnosis , Skin Neoplasms/drug therapy , Spironolactone
3.
ACS Nano ; 16(4): 5743-5751, 2022 Apr 26.
Article in English | MEDLINE | ID: mdl-35377604

ABSTRACT

The clean production of hydrogen from water using sunlight has emerged as a sustainable alternative toward large-scale energy generation and storage. However, designing photoactive semiconductors that are suitable for both light harvesting and water splitting is a pivotal challenge. Atomically thin transition metal dichalcogenides (TMD) are considered as promising photocatalysts because of their wide range of available electronic properties and compositional variability. However, trade-offs between carrier transport efficiency, light absorption, and electrochemical reactivity have limited their prospects. We here combine two approaches that synergistically enhance the efficiency of photocarrier generation and electrocatalytic efficiency of two-dimensional (2D) TMDs. The arrangement of monolayer WS2 and MoS2 into a heterojunction and subsequent nanostructuring into a nanoscroll (NS) yields significant modifications of fundamental properties from its constituents. Spectroscopic characterization and ab initio simulation demonstrate the beneficial effects of straining and wall interactions on the band structure of such a heterojunction-NS that enhance the electrochemical reaction rate by an order of magnitude compared to planar heterojunctions. Phototrapping in this NS further increases the light-matter interaction and yields superior photocatalytic performance compared to previously reported 2D material catalysts and is comparable to noble-metal catalyst systems in the photoelectrochemical hydrogen evolution reaction (PEC-HER) process. Our approach highlights the potential of morphologically varied TMD-based catalysts for PEC-HER.

4.
Am J Dermatopathol ; 44(1): 66-69, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34132667

ABSTRACT

ABSTRACT: Basaloid follicular hamartoma (BFH) is a rare, benign follicular neoplasm which typically presents as brown to skin-colored papules on the face, scalp, and trunk. Histologically, BFH consists of cords and strands of basaloid cells forming cystic structures with scant stroma and should be distinguished from infundibulocystic basal cell carcinoma to avoid overly aggressive treatment. Although BFH has been found to be associated with distinct syndromes, including alopecia, myasthenia gravis, and cystic fibrosis, there is often clinical, histopathologic, and genetic overlap with nevoid basal cell carcinoma syndrome (NBCCS). In this article, we describe a case of a 13-year-old patient with NBCCS who presented with multiple BFHs and propose that it its inclusion into the diagnostic criteria for NBCCS be considered.


Subject(s)
Basal Cell Nevus Syndrome/pathology , Basal Cell Nevus Syndrome/physiopathology , Hair Diseases/pathology , Hamartoma/pathology , Adolescent , Basal Cell Nevus Syndrome/diagnosis , Basal Cell Nevus Syndrome/genetics , Hair Diseases/etiology , Hair Follicle/pathology , Hamartoma/etiology , Humans , Male
5.
Phys Chem Chem Phys ; 22(36): 20643-20657, 2020 Sep 23.
Article in English | MEDLINE | ID: mdl-32895678

ABSTRACT

Complex coacervation has become a prominent area of research in the fields of food science, personal care, drug stabilization, and more. However, little has been reported on the kinetics of assembly of coacervation itself. Here, we describe a simple, low-cost way of looking at the kinetics of coacervation by creating poorly mixed samples. In particular, we examine how polymer chain length, the patterning and symmetry of charges on the oppositely charged polyelectrolytes, and the presence of salt and a zwitterionic buffer affect the kinetics of complex coacervation. Our results suggest an interesting relationship between the time for equilibration and the order of addition of polymers with asymmetric patterns of charge. Furthermore, we demonstrated that increasing polymer chain length resulted in a non-monotonic trend in the sample equilibration times as a result of opposing factors such as excluded volume and diffusion. We also observed differences in the rate of sample equilibration based on the presence of a neutral, zwitterionic buffer, as well as the presence and identity of added salt, consistent with previous reports of salt-specific effects on the rheology of complex coacervates. While not a replacement for more advanced characterization strategies, this turbidity-based method could serve as a screening tool to identify interesting and unique phenomena for further study.

6.
Melanoma Res ; 30(6): 594-598, 2020 12.
Article in English | MEDLINE | ID: mdl-32976222

ABSTRACT

Mounting evidence supports a role for dysregulated long non-coding RNAs (lncRNA) in the development of many cancers. A recently discovered function of lncRNAs is to act as microRNA (miR) decoys or competing endogenous RNAs, which sequester specific miRs and relieve negative regulation of mRNA expression by miRs. Although a large number of non-coding RNAs are thought to function as competing endogenous RNAs, miR-sequestering lncRNAs involved in nevus to melanoma transformation remain largely unknown. In this study, we applied a bioinformatics approach to a unique dataset of benign melanocytic nevi and primary melanomas of the skin in order to fill this research gap. We modified a previously published miR target prediction algorithm, RNAhybrid, and improved its search efficiency. We reported the presence of many lncRNAs and miRs deregulated when transitioning from a senescence-like state of nevi to melanoma. We provided evidence of a relatively new and understudied mechanism of gene regulation during this process and identified for the first time lncRNAs (n = 122) that may potentially function as miR decoys as well as their target miRs during nevus to melanoma transformation. The knowledge presented here can be employed for developing biomarkers for diagnostic and risk stratification purposes.


Subject(s)
Melanoma/genetics , MicroRNAs/metabolism , Nevus/genetics , RNA, Long Noncoding/metabolism , Skin Neoplasms/genetics , Humans
8.
Am J Dermatopathol ; 42(11): 854-857, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32310862

ABSTRACT

Cutaneous melanomas may demonstrate a variety of histopathological features and genetic abnormalities. Melanomas that arise in the setting of blue nevi, also known as "malignant blue nevus" or melanoma ex blue nevus (MBN), share a similar histopathological and mutational profile with uveal melanoma. Most uveal melanomas show characteristic GNA11 or GNAQ mutations; additional BAP1 mutation or loss is associated with the highest risk of metastasis and worst prognosis. However, the significance of BAP1 loss in melanomas ex blue nevus remains unclear. We present a case of MBN arising from the scalp of a 21-year-old woman. The diagnosis was established on histopathological findings demonstrating a markedly atypical melanocytic proliferation with increased mitotic activity, necrosis, and a focus of angiolymphatic invasion. Immunohistochemical analysis demonstrated the absence of BAP1 nuclear expression within tumor cells. Next generation sequencing detected GNA11 Q209L mutation and BAP1 loss (chromosome 3p region loss), supporting the diagnosis. We reviewed another 21 MBN cases with reported BAP1 status from the literature. MBN with BAP1 loss presented at a younger average age (41 vs. 61 years), demonstrated larger average lesion thickness (9.0 vs. 7.3 mm), and had a higher rate of metastasis (50% vs. 33%) compared with BAP1-retained MBN. BAP1 expression studies may assist in the diagnosis and management of MBN, but further research is needed.


Subject(s)
GTP-Binding Protein alpha Subunits/genetics , Melanoma/genetics , Nevus, Blue/pathology , Skin Neoplasms/genetics , Tumor Suppressor Proteins/genetics , Ubiquitin Thiolesterase/genetics , Female , Humans , Melanoma/pathology , Nevus, Blue/genetics , Scalp/pathology , Skin Neoplasms/pathology , Young Adult
11.
ACS Cent Sci ; 5(4): 709-718, 2019 Apr 24.
Article in English | MEDLINE | ID: mdl-31041391

ABSTRACT

Charged polymers are ubiquitous in biological systems because electrostatic interactions can drive complicated structure formation and respond to environmental parameters such as ionic strength and pH. In these systems, function emerges from sophisticated molecular design; for example, intrinsically disordered proteins leverage specific sequences of monomeric charges to control the formation and function of intracellular compartments known as membraneless organelles. The role of a charged monomer sequence in dictating the strength of electrostatic interactions remains poorly understood despite extensive evidence that sequence is a powerful tool biology uses to tune soft materials. In this article, we use a combination of theory, experiment, and simulation to establish the physical principles governing sequence-driven control of electrostatic interactions. We predict how arbitrary sequences of charge give rise to drastic changes in electrostatic interactions and correspondingly phase behavior. We generalize a transfer matrix formalism that describes a phase separation phenomenon known as "complex coacervation" and provide a theoretical framework to predict the phase behavior of charge sequences. This work thus provides insights into both how charge sequence is used in biology and how it could be used to engineer properties of synthetic polymer systems.

13.
Nat Commun ; 8(1): 1273, 2017 11 02.
Article in English | MEDLINE | ID: mdl-29097695

ABSTRACT

Biomacromolecules rely on the precise placement of monomers to encode information for structure, function, and physiology. Efforts to emulate this complexity via the synthetic control of chemical sequence in polymers are finding success; however, there is little understanding of how to translate monomer sequence to physical material properties. Here we establish design rules for implementing this sequence-control in materials known as complex coacervates. These materials are formed by the associative phase separation of oppositely charged polyelectrolytes into polyelectrolyte dense (coacervate) and polyelectrolyte dilute (supernatant) phases. We demonstrate that patterns of charges can profoundly affect the charge-charge associations that drive this process. Furthermore, we establish the physical origin of this pattern-dependent interaction: there is a nuanced combination of structural changes in the dense coacervate phase and a 1D confinement of counterions due to patterns along polymers in the supernatant phase.

14.
JCI Insight ; 2(9)2017 May 04.
Article in English | MEDLINE | ID: mdl-28469092

ABSTRACT

BACKGROUND: Melanoma is a heterogeneous malignancy. We set out to identify the molecular underpinnings of high-risk melanomas, those that are likely to progress rapidly, metastasize, and result in poor outcomes. METHODS: We examined transcriptome changes from benign states to early-, intermediate-, and late-stage tumors using a set of 78 treatment-naive melanocytic tumors consisting of primary melanomas of the skin and benign melanocytic lesions. We utilized a next-generation sequencing platform that enabled a comprehensive analysis of protein-coding and -noncoding RNA transcripts. RESULTS: Gene expression changes unequivocally discriminated between benign and malignant states, and a dual epigenetic and immune signature emerged defining this transition. To our knowledge, we discovered previously unrecognized melanoma subtypes. A high-risk primary melanoma subset was distinguished by a 122-epigenetic gene signature ("epigenetic" cluster) and TP53 family gene deregulation (TP53, TP63, and TP73). This subtype associated with poor overall survival and showed enrichment of cell cycle genes. Noncoding repetitive element transcripts (LINEs, SINEs, and ERVs) that can result in immunostimulatory signals recapitulating a state of "viral mimicry" were significantly repressed. The high-risk subtype and its poor predictive characteristics were validated in several independent cohorts. Additionally, primary melanomas distinguished by specific immune signatures ("immune" clusters) were identified. CONCLUSION: The TP53 family of genes and genes regulating the epigenetic machinery demonstrate strong prognostic and biological relevance during progression of early disease. Gene expression profiling of protein-coding and -noncoding RNA transcripts may be a better predictor for disease course in melanoma. This study outlines the transcriptional interplay of the cancer cell's epigenome with the immune milieu with potential for future therapeutic targeting. FUNDING: National Institutes of Health (CA154683, CA158557, CA177940, CA087497-13), Tisch Cancer Institute, Melanoma Research Foundation, the Dow Family Charitable Foundation, and the Icahn School of Medicine at Mount Sinai.

15.
Immunity ; 42(1): 186-98, 2015 Jan 20.
Article in English | MEDLINE | ID: mdl-25607463

ABSTRACT

Most B-cell lymphomas arise in the germinal center (GC), where humoral immune responses evolve from potentially oncogenic cycles of mutation, proliferation, and clonal selection. Although lymphoma gene expression diverges significantly from GC B cells, underlying mechanisms that alter the activities of corresponding regulatory elements (REs) remain elusive. Here we define the complete pathogenic circuitry of human follicular lymphoma (FL), which activates or decommissions REs from normal GC B cells and commandeers enhancers from other lineages. Moreover, independent sets of transcription factors, whose expression was deregulated in FL, targeted commandeered versus decommissioned REs. Our approach revealed two distinct subtypes of low-grade FL, whose pathogenic circuitries resembled GC B or activated B cells. FL-altered enhancers also were enriched for sequence variants, including somatic mutations, which disrupt transcription-factor binding and expression of circuit-linked genes. Thus, the pathogenic regulatory circuitry of FL reveals distinct genetic and epigenetic etiologies for GC B-cell transformation.


Subject(s)
B-Lymphocytes/physiology , Gene Regulatory Networks , Germinal Center/pathology , Lymphoma, B-Cell/genetics , Regulatory Elements, Transcriptional/immunology , Adult , Aged , Cell Transformation, Neoplastic , Epigenesis, Genetic , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Lymphocyte Activation/genetics , Male , Middle Aged , Mutation/genetics , Regulatory Elements, Transcriptional/genetics , Transcription Factors/metabolism
16.
PLoS One ; 8(9): e75012, 2013.
Article in English | MEDLINE | ID: mdl-24040378

ABSTRACT

There is compelling in vivo evidence from reports on human genetic mutations and transgenic mice that some microRNAs (miRNAs) play an important functional role in regulating skeletal development and growth. A number of published in vitro studies also point toward a role for miRNAs in controlling chondrocyte gene expression and differentiation. However, information on miRNAs that may regulate a specific phase of chondrocyte differentiation (i.e. production of progenitor, differentiated or hypertrophic chondrocytes) is lacking. To attempt to bridge this knowledge gap, we have investigated miRNA expression patterns in human embryonic cartilage tissue. Specifically, a developmental time point was selected, prior to endochondral ossification in the embryonic limb, to permit analysis of three distinct populations of chondrocytes. The location of chondroprogenitor cells, differentiated chondrocytes and hypertrophic chondrocytes in gestational day 54-56 human embryonic limb tissue sections was confirmed both histologically and by specific collagen expression patterns. Laser capture microdissection was utilized to separate the three chondrocyte populations and a miRNA profiling study was carried out using TaqMan® OpenArray® Human MicroRNA Panels (Applied Biosystems®). Here we report on abundantly expressed miRNAs in human embryonic cartilage tissue and, more importantly, we have identified miRNAs that are significantly differentially expressed between precursor, differentiated and hypertrophic chondrocytes by 2-fold or more. Some of the miRNAs identified in this study have been described in other aspects of cartilage or bone biology, while others have not yet been reported in chondrocytes. Finally, a bioinformatics approach was applied to begin to decipher developmental cellular pathways that may be regulated by groups of differentially expressed miRNAs during distinct stages of chondrogenesis. Data obtained from this work will serve as an important resource of information for the field of cartilage biology and will enhance our understanding of miRNA-driven mechanisms regulating cartilage and endochondral bone development, regeneration and repair.


Subject(s)
Cartilage/embryology , Cartilage/metabolism , Chondrocytes/cytology , Gene Expression Regulation, Developmental , MicroRNAs/metabolism , Bone and Bones/metabolism , Cell Differentiation , Chondrocytes/metabolism , Computational Biology , Femur/embryology , Gene Expression Profiling , Humans , Laser Capture Microdissection , Microscopy, Fluorescence , Regeneration , Stem Cells/cytology , Tibia/embryology
17.
PLoS One ; 8(6): e67980, 2013.
Article in English | MEDLINE | ID: mdl-23826350

ABSTRACT

A major goal of cancer genome sequencing is to identify mutations or other somatic alterations that can be targeted by selective and specific drugs. dGene is an annotation tool designed to rapidly identify genes belonging to one of ten druggable classes that are frequently targeted in cancer drug development. These classes were comprehensively populated by combining and manually curating data from multiple specialized and general databases. dGene was used by The Cancer Genome Atlas squamous cell lung cancer project, and here we further demonstrate its utility using recently released breast cancer genome sequencing data. dGene is designed to be usable by any cancer researcher without the need for support from a bioinformatics specialist. A full description of dGene and options for its implementation are provided here.


Subject(s)
Antineoplastic Agents/pharmacology , Molecular Sequence Annotation , Mutation , Neoplasms/genetics , Computational Biology , Genome, Human , Humans , Polymorphism, Single Nucleotide
18.
BMC Genomics ; 14: 84, 2013 Feb 06.
Article in English | MEDLINE | ID: mdl-23387820

ABSTRACT

BACKGROUND: The regenerative response of Schwann cells after peripheral nerve injury is a critical process directly related to the pathophysiology of a number of neurodegenerative diseases. This SC injury response is dependent on an intricate gene regulatory program coordinated by a number of transcription factors and microRNAs, but the interactions among them remain largely unknown. Uncovering the transcriptional and post-transcriptional regulatory networks governing the Schwann cell injury response is a key step towards a better understanding of Schwann cell biology and may help develop novel therapies for related diseases. Performing such comprehensive network analysis requires systematic bioinformatics methods to integrate multiple genomic datasets. RESULTS: In this study we present a computational pipeline to infer transcription factor and microRNA regulatory networks. Our approach combined mRNA and microRNA expression profiling data, ChIP-Seq data of transcription factors, and computational transcription factor and microRNA target prediction. Using mRNA and microRNA expression data collected in a Schwann cell injury model, we constructed a regulatory network and studied regulatory pathways involved in Schwann cell response to injury. Furthermore, we analyzed network motifs and obtained insights on cooperative regulation of transcription factors and microRNAs in Schwann cell injury recovery. CONCLUSIONS: This work demonstrates a systematic method for gene regulatory network inference that may be used to gain new information on gene regulation by transcription factors and microRNAs.


Subject(s)
Computational Biology/methods , Gene Regulatory Networks , MicroRNAs/genetics , MicroRNAs/metabolism , Peripheral Nerve Injuries/pathology , Schwann Cells/metabolism , Transcription Factors/metabolism , Animals , Chromatin Immunoprecipitation , Early Growth Response Protein 2/metabolism , Gene Expression Profiling , Gene Expression Regulation , Genomics , Humans , Mice , Myelin Sheath/physiology , Peripheral Nerve Injuries/genetics , Peripheral Nerve Injuries/metabolism , Peripheral Nerve Injuries/physiopathology , RNA, Messenger/genetics , RNA, Messenger/metabolism
19.
Blood ; 119(14): 3295-305, 2012 Apr 05.
Article in English | MEDLINE | ID: mdl-22343916

ABSTRACT

Two distinct types of Flk-1(+) mesoderm, hemangiogenic and cardiogenic, are thought to contribute to blood, vessel, and cardiac cell lineages. However, our understanding of how Flk-1(+) mesoderm is specified is currently limited. In the present study, we investigated whether ER71, an Ets transcription factor essential for hematopoietic and endothelial cell lineage development, could modulate the hemangiogenic or cardiogenic outcome of the Flk-1(+) mesoderm. We show that Flk-1(+) mesoderm can be divided into Flk-1(+)PDGFRα(-) hemangiogenic and Flk-1(+)PDGFRα(+) cardiogenic mesoderm. ER71-deficient embryonic stem cells produced only the Flk-1(+)PDGFRα(+) cardiogenic mesoderm, which generated SMCs and cardiomyocytes. Enforced ER71 expression in the wild-type embryonic stem cells skewed toward the Flk-1(+)PDGFRα(-) mesoderm formation, which generated hematopoietic and endothelial cells. Whereas hematopoietic and endothelial cell genes were positively regulated by ER71, cardiac and Wnt signaling pathway genes were negatively regulated by ER71. We show that ER71 could inhibit Wnt signaling in VE-cadherin-independent as well as VE-cadherin-dependent VE-cadherin/ß-catenin/Flk-1 complex formation. Enforced ß-catenin could rescue cardiogenic mesoderm in the context of ER71 overexpression. In contrast, ER71-deficient Flk-1(+) mesoderm displayed enhanced Wnt signaling, which was reduced by ER71 re-introduction. We provide the molecular basis for the antagonistic relationship between hemangiogenic and cardiogenic mesoderm specification by ER71 and Wnt signaling.


Subject(s)
Mesoderm/metabolism , Myocytes, Cardiac/metabolism , Neovascularization, Physiologic , Transcription Factors/metabolism , Vascular Endothelial Growth Factor Receptor-2/metabolism , Wnt Signaling Pathway , Animals , Antigens, CD/genetics , Antigens, CD/metabolism , Cadherins/genetics , Cadherins/metabolism , Cell Line , Cluster Analysis , Embryonic Stem Cells/metabolism , Endothelial Cells/metabolism , Gene Expression Profiling , Gene Expression Regulation , Hematopoietic Stem Cells/metabolism , Mice , Mice, 129 Strain , Mice, Inbred C57BL , Mice, Knockout , Myocytes, Smooth Muscle/metabolism , Neovascularization, Physiologic/genetics , Protein Binding , Receptor, Platelet-Derived Growth Factor alpha/metabolism , Transcription Factors/genetics , beta Catenin/genetics , beta Catenin/metabolism
20.
J Neurosci ; 31(48): 17358-69, 2011 Nov 30.
Article in English | MEDLINE | ID: mdl-22131398

ABSTRACT

In the peripheral nervous system, Schwann cells (SCs) surrounding damaged axons undergo an injury response that is driven by an intricate transcriptional program and is critical for nerve regeneration. To examine whether these injury-induced changes in SCs are also regulated posttranscriptionally by miRNAs, we performed miRNA expression profiling of mouse sciatic nerve distal segment after crush injury. We also characterized the SC injury response in mice containing SCs with disrupted miRNA processing due to loss of Dicer. We identified 87 miRNAs that were expressed in mouse adult peripheral nerve, 48 of which were dynamically regulated after nerve injury. Most of these injury-regulated SC miRNAs were computationally predicted to inhibit drivers of SC dedifferentiation/proliferation and thereby re-enforce the transcriptional program driving SC remyelination. SCs deficient in miRNAs manifested a delay in the transition between the distinct differentiation states required to support peripheral nerve regeneration. Among the miRNAs expressed in adult mouse SCs, miR-34a and miR-140 were identified as functional regulators of SC dedifferentiation/proliferation and remyelination, respectively. We found that miR-34a interacted with positive regulators of dedifferentiation and proliferation such as Notch1 and Ccnd1 to control cell cycle dynamics in SCs. miR-140 targeted the transcription factor Egr2, a master regulator of myelination, and modulated myelination in DRG/SC cocultures. Together, these results demonstrate that SC miRNAs are important modulators of the SC regenerative response after nerve damage.


Subject(s)
Cell Dedifferentiation/genetics , Gene Silencing , MicroRNAs/metabolism , Schwann Cells/metabolism , Sciatic Nerve/injuries , Animals , Axons/metabolism , Cells, Cultured , Gene Expression Regulation , Mice , MicroRNAs/genetics , Nerve Crush , Nerve Regeneration/physiology , Sciatic Nerve/metabolism
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