Insights into Pathomechanisms and Treatment Development in Heritable Ectopic Mineralization Disorders: Summary of the PXE International Biennial Research Symposium-2016

Pseudoxanthoma elasticum is a prototype of heritable ectopic mineralization disorders, with phenotypic overlap with generalized arterial calcification of infancy and arterial calcification due to CD73 deficiency. Recent observations have suggested that the reduced inorganic pyrophosphate/phosphate ratio is the cause of soft connective tissue mineralization in these disorders. PXE International, a patient advocacy organization, supports research in part by sponsoring biennial research symposia on these disorders; the latest meeting was held in September 2016 at Thomas Jefferson University, Philadelphia. This report summarizes the progress in pseudoxanthoma elasticum and other ectopic mineralization disorders, as presented in the symposium, with focus on translational aspects of precision medicine toward improved diagnostics and treatment development for these currently intractable disorders.

The effect of polymeric formula on enterocyte differentiation

Exclusive enteral nutrition is established as an initial therapy to induce remission in active Crohn's disease (CD), especially in children, but the mechanisms of action of this therapy are yet to be fully defined. Intestinal alkaline phosphatase (IAP), a recognised marker of enterocyte differentiation, is implicated in the innate gut immune response to enteric pathogens. Using the Caco-2 human adenocarcinoma cell line, this study showed that the incubation of human cells with a polymeric formula (PF) resulted in a dose-dependent increase in the expression of IAP on the cell surface. While further investigation is required to determine the pathway(s) involved, this finding suggests that cell surface-associated IAP may be an aspect of the gut's innate immune response to pathogenic bacteria that is strengthened by PF in the setting of CD.

Understanding the Genomic Structure of Copy-Number Variation of the Low-Affinity Fcγ Receptor Region Allows Confirmation of the Association of FCGR3B Deletion with Rheumatoid Arthritis

Fcγ receptors are a family of cell-surface receptors that are expressed by a host of different innate and adaptive immune cells, and mediate inflammatory responses by binding the Fc portion of immunoglobulin G. In humans, five low-affinity receptors are encoded by the genes FCGR2A, FCGR2B, FCGR2C, FCGR3A, and FCGR3B, which are located in an 82.5-kb segmental tandem duplication on chromosome 1q23.3, which shows extensive copy-number variation (CNV). Deletions of FCGR3B have been suggested to increase the risk of inflammatory diseases such as systemic lupus erythematosus and rheumatoid arthritis (RA). In this study, we identify the deletion breakpoints of FCGR3B deletion alleles in the UK population and endogamous native American population, and show that some but not all alleles are likely to be identical-by-descent. We also localize a duplication breakpoint, confirming that the mechanism of CNV generation is nonallelic homologous recombination, and identify several alleles with gene conversion events using fosmid sequencing data. We use information on the structure of the deletion alleles to distinguish FCGR3B deletions from FCGR3A deletions in whole-genome array comparative genomic hybridization (aCGH) data. Reanalysis of published aCGH data using this approach supports association of FCGR3B deletion with increased risk of RA in a large cohort of 1,982 cases and 3,271 controls (odds ratio 1.61, P = 2.9×10-3 ).

Compared to the amniotic membrane, Wharton's jelly may be a more suitable source of mesenchymal stem cells for cardiovascular tissue engineering and clinical regeneration

BACKGROUND

The success of developing cardiovascular tissue engineering (CTE) grafts greatly needs a readily available cell substitute for endothelial and interstitial cells. Perinatal annexes have been proposed as a valuable source of mesenchymal stem cells (MSCs) for tissue engineering and regenerative medicine. The objective of the present study is to evaluate the potential of human Wharton's jelly MSCs (WJ-MSCs) and amniotic membrane MSCs (AM-MSCs) as a seeding cell in CTE and cardiovascular regenerative medicine.

METHODS

WJ-MSCs/AM-MSCs were isolated and characterized in vitro according to their morphology, proliferation, self-renewal, phenotype, and multipotency. More importantly, the characteristics of hemocompatibility, extracellular matrix deposition, and gene expression and viability of both MSCs were investigated.

RESULTS

Fibroblast-like human WJ-MSCs and AM-MSCs were successfully isolated and positively expressed the characteristic markers CD73, CD90, and CD105 but were negative for CD34, CD45, and HLA-DR. Both MSCs shared trilineage differentiation toward the adipogenic, osteogenic, and chondrogenic lineages. The proliferative and self-renewal capacity of WJ-MSCs was significantly higher than that of AM-MSCs (P < 0.001). WJ-MSCs provided comparable properties of antiplatelet adhesion and did not activate the coagulation cascade to endothelial cells. However, aggregated platelets were visualized on the surface of AM-MSCs-derived cell sheets and the intrinsic pathway was activated. Furthermore, WJ-MSCs have superior properties of collagen deposition and higher viability than AM-MSCs during cell sheet formation.

CONCLUSIONS

This study highlights that WJ-MSCs could act as a functional substitute of endothelial and interstitial cells, which could serve as an appealing and practical single-cell source for CTE and regenerative therapy.

Mesothelin/mucin 16 signaling in activated portal fibroblasts regulates cholestatic liver fibrosis

Cholestatic liver fibrosis is caused by obstruction of the biliary tract and is associated with early activation of portal fibroblasts (PFs) that express Thy-1, fibulin 2, and the recently identified marker mesothelin (MSLN). Here, we have demonstrated that activated PFs (aPFs) and myofibroblasts play a critical role in the pathogenesis of liver fibrosis induced by bile duct ligation (BDL). Conditional ablation of MSLN+ aPFs in BDL-injured mice attenuated liver fibrosis by approximately 50%. Similar results were observed in MSLN-deficient mice (Msln-/- mice) or mice deficient in the MSLN ligand mucin 16 (Muc16-/- mice). In vitro analysis revealed that MSLN regulates TGF-β1-inducible activation of WT PFs by disrupting the formation of an inhibitory Thy-1-TGFβRI complex. MSLN also facilitated the FGF-mediated proliferation of WT aPFs. Therapeutic administration of anti-MSLN-blocking Abs attenuated BDL-induced fibrosis in WT mice. Liver specimens from patients with cholestatic liver fibrosis had increased numbers of MSLN+ aPFs/myofibroblasts, suggesting that MSLN may be a potential target for antifibrotic therapy.

The cohesion stabilizer sororin favors DNA repair and chromosome segregation during mouse oocyte meiosis

Maintenance and timely termination of cohesion on chromosomes ensures accurate chromosome segregation to guard against aneuploidy in mammalian oocytes and subsequent chromosomally abnormal pregnancies. Sororin, a cohesion stabilizer whose relevance in antagonizing the anti-cohesive property of Wings-apart like protein (Wapl), has been characterized in mitosis; however, the role of Sororin remains unclear during mammalian oocyte meiosis. Here, we show that Sororin is required for DNA damage repair and cohesion maintenance on chromosomes, and consequently, for mouse oocyte meiotic program. Sororin is constantly expressed throughout meiosis and accumulates on chromatins at germinal vesicle (GV) stage/G2 phase. It localizes onto centromeres from germinal vesicle breakdown (GVBD) to metaphase II stage. Inactivation of Sororin compromises the GVBD and first polar body extrusion (PBE). Furthermore, Sororin inactivation induces DNA damage indicated by positive γH2AX foci in GV oocytes and precocious chromatin segregation in MII oocytes. Finally, our data indicate that PlK1 and MPF dissociate Sororin from chromosome arms without affecting its centromeric localization. Our results define Sororin as a determinant during mouse oocyte meiotic maturation by favoring DNA damage repair and chromosome separation, and thereby, maintaining the genome stability and generating haploid gametes.

Cripto-1 promotes epithelial-mesenchymal transition in prostate cancer via Wnt/β-catenin signaling

The Cripto-1 (CR-1) derived EGF-CFC family was overexpressed in tumor development enhancing proliferation, epithelial-mesenchymal transition (EMT) and migration of tumor cells. However, correlation between CR-1 and prostate cancer (PCa) remains still unclear. In the present study, we proved that CR-1 was expressed in PCa and its function was in the progression of PCa. Compared with benign prostatic hyperplasia (BPH) tissues, we confirmed that PCa tissues had high expression of CR-1 by immunohistochemistry and statistical data showed that CR-1 promoted properties of EMT in PCa tissues, including the downregulation of the cell adhesion molecules β-catenin (membrane) and E-cadherin while upregulating transcription factors β-catenin. Overexpression of CR-1 had close relationship with PSA, Gleason, clinical staging and lymph node metastasis in PCa patients. Then, we found that PC-3 cells transfected with CR-1-shRNA inhibited EMT using RT-PCR, RT-qPCR, western blotting and immunofluorescence. Also, we evaluated cell invasive ability in vitro by transwell and wound-healing assay. Our data showed that transfected CR-1-shRNA altered EMT including β-catenin, E-cadherin, c-myc, GSK-3, p-GSK and Wnt/β-catenin pathway in PC-3. It also suppressed PC-3 cell migration. Additionally, our results displayed that Licl had antitumor activity against PC-3 through the inhibition of Wnt/β-catenin pathway. Inhibition of cell viability was dose-time dependent. The present study proved that CR-1 regulates EMT of PCa by Wnt/β-catenin pathway. Hence, CR-1 may provide a new biological marker, and possibly contributes to clinical treatment against PCa.

Ecto-5' -Nucleotidase CD73 (NT5E), vitamin D receptor and FGF23 gene polymorphisms may play a role in the development of calcific uremic arteriolopathy in dialysis patients - Data from the German Calciphylaxis Registry

Introduction

Calciphylaxis/calcific uremic arteriolopathy affects mainly end-stage kidney disease patients but is also associated with malignant disorders such as myeloma, melanoma and breast cancer. Genetic risk factors of calciphylaxis have never been studied before.

Methods

We investigated 10 target genes using a tagging SNP approach: the genes encoding CD73/ ecto-5'-nucleotidase (purinergic pathway), Matrix Gla protein, Fetuin A, Bone Gla protein, VKORC1 (all related to intrinsic calcification inhibition), calcium-sensing receptor, FGF23, Klotho, vitamin D receptor, stanniocalcin 1 (all related to CKD-MBD). 144 dialysis patients from the German calciphylaxis registry were compared with 370 dialysis patients without history of CUA. Genotyping was performed using iPLEX Gold MassARRAY(Sequenom, San Diego, USA), KASP genotyping chemistry (LGC, Teddington, Middlesex, UK) or sequencing. Statistical analysis comprised logistic regression analysis with adjustment for age and sex.

Results

165 SNPs were finally analyzed and 6 SNPs were associated with higher probability for calciphylaxis (OR>1) in our cohort. Nine SNPs of three genes (CD73, FGF23 and Vitamin D receptor) reached nominal significance (p< 0.05), but did not reach statistical significance after correction for multiple testing. Of the CD73 gene, rs4431401 (OR = 1.71, 95%CI 1.08–2.17, p = 0.023) and rs9444348 (OR = 1.48, 95% CI 1.11–1.97, p = 0.008) were associated with a higher probability for CUA. Of the FGF23 and VDR genes, rs7310492, rs11063118, rs13312747 and rs17882106 were associated with a higher probability for CUA.

Conclusion

Polymorphisms in the genes encoding CD73, vitamin D receptor and FGF23 may play a role in calciphylaxis development. Although our study is the largest genetic study on calciphylaxis, it is limited by the low sample sizes. It therefore requires replication in other cohorts if available.

AKT Axis, miR-21, and RECK Play Pivotal Roles in Dihydroartemisinin Killing Malignant Glioma Cells

Dihydroartemisinin (DHA), a semi-synthetic derivative of artemisinin, is known to play important roles in inhibiting proliferation rate, inducing apoptosis, as well as hindering the metastasis and invasion of glioma cells, but the underlying mechanisms are still unclear so far. In this study, methyl thiazolyl tetrazolium (MTT), colony-forming, wound healing, invasion, and apoptosis assays were performed to investigate the effect of DHA on malignant glioma cells. Results showed that DHA induced apoptosis of malignant glioma cells through Protein Kinase B (AKT) axis, induced death of malignant glioma cells by downregulating miR-21, and inhibited the invasion of malignant glioma cells corresponding with up-regulation of the reversion-inducing-cysteine-rich protein with kazal motifs (RECK). These results revealed that AKT axis, miR-21, and RECK play pivotal roles in DHA killing malignant glioma cells, suggesting that DHA is a potential agent for treating glioma.

Minor variant of rs 16827043 in the iron regulator hemojuvelin gene (HJV) contributes to hypertension: The TAMRISK study

It is known that iron overload may lead to an increased risk for many diseases. According to GWAS studies, iron regulatory protein HFE gene variant H63D (rs1799945) was associated with hypertension, an observation which we were able to confirm also in our TAMRISK cohort. Thus, it is possible that abnormalities in iron homeostasis may predispose to hypertension. This prompted us to study whether there is an association between hypertension and another iron overload-associated gene, hemojuvelin (HJV), which has 2 common polymorphic sites (rs 16827043, rs7536827).The study included 336 hypertensive cases and 480 controls. All participants were 50- year-old Finnish men and women, and the data was collected from the Tampere adult population cardiovascular risk study (TAMRISK). Genotypes were determined using Competitive Allelic Specific PCR (KASP).We found that the minor variant of the HJV polymorphic site rs16827043 (G-allele) is a statistically significant factor associated with hypertension among 50 year-old individuals compared with the AA genotype carriers (OR = 1.66, 95% CI: 1.06 - 2.60, P = 0.03). The risk was even higher when overweight subjects (BMI>30) were excluded from the analyses. For the other polymorphic variant rs7536827, association with hypertension was found only among normal or slightly overweight A-allele carriers.In conclusion, HJV genetic variants were associated with essential hypertension in Finnish subjects from the TAMRISK cohort. Previous studies together with the present one indicate that individuals with possible dysregulation of iron metabolism may have higher risk for hypertension than those with normal iron homeostasis.

Identification of MiR-21-5p as a Functional Regulator of Mesothelin Expression Using MicroRNA Capture Affinity Coupled with Next Generation Sequencing

MicroRNAs (miRNAs) are small non-coding RNAs that regulate mRNA expression mainly by silencing target transcripts via binding to miRNA recognition elements (MREs) in the 3'untranslated region (3'UTR). The identification of bona fide targets is challenging for researchers working on the functional aspect of miRNAs. Recently, we developed a method (miR-CATCH) based on biotinylated DNA antisense oligonucleotides that capture the mRNA of interest and facilitates the characterisation of miRNAs::mRNA interactions in a physiological cellular context. Here, the miR-CATCH technique was applied to the mesothelin (MSLN) gene and coupled with next generation sequencing (NGS), to identify miRNAs that regulate MSLN mRNA and that may be responsible for its increased protein levels found in malignant pleural mesothelioma (MPM). Biotinylated MSLN oligos were employed to isolate miRNA::MSLN mRNA complexes from a normal cell line (Met-5A) which expresses low levels of MSLN. MiRNAs targeting the MSLN mRNA were identified by NGS and miR-21-5p and miR-100-5p were selected for further validation analyses. MiR-21-5p was shown to be able to modulate MSLN expression in miRNA mimic experiments in a panel of malignant and non-malignant cell lines. Further miRNA inhibitor experiments and luciferase assays in Mero-14 cells validated miR-21-5p as a true regulator of MSLN. Moreover, in vitro experiments showed that treatment with miR-21-5p mimic reduced proliferation of MPM cell lines. Altogether, this work shows that the miR-CATCH technique, coupled with NGS and in vitro validation, represents a reliable method to identify native miRNA::mRNA interactions. MiR-21-5p is suggested as novel regulator of MSLN with a possible functional role in cellular growth.

The Interplay Between Neutrophils and CD8+ T Cells Improves Survival in Human Colorectal Cancer

Purpose: Tumor infiltration by different T lymphocyte subsets is known to be associated with favorable prognosis in colorectal cancer. Still debated is the role of innate immune system. We investigated clinical relevance, phenotypes, and functional features of colorectal cancer-infiltrating CD66b⁺ neutrophils and their crosstalk with CD8⁺ T cells.Experimental Design: CD66b⁺ and CD8⁺ cell infiltration was analyzed by IHC on a tissue microarray including >650 evaluable colorectal cancer samples. Phenotypic profiles of tissue-infiltrating and peripheral blood CD66b⁺ cells were evaluated by flow cytometry. CD66b⁺/CD8⁺ cells crosstalk was investigated by in vitro experiments.Results: CD66b⁺ cell infiltration in colorectal cancer is significantly associated with increased survival. Interestingly, neutrophils frequently colocalize with CD8⁺ T cells in colorectal cancer. Functional studies indicate that although neutrophils are devoid of direct antitumor potential, coculture with peripheral blood or tumor-associated neutrophils (TAN) enhances CD8⁺ T-cell activation, proliferation, and cytokine release induced by suboptimal concentrations of anti-CD3 mAb. Moreover, under optimal activation conditions, CD8⁺ cell stimulation in the presence of CD66b⁺ cells results in increasing numbers of cells expressing CD45RO/CD62L "central memory" phenotype. Importantly, combined tumor infiltration by CD66b⁺ and CD8⁺ T lymphocytes is associated with significantly better prognosis, as compared with CD8⁺ T-cell infiltration alone.Conclusions: Neutrophils enhance the responsiveness of CD8⁺ T cells to T-cell receptor triggering. Accordingly, infiltration by neutrophils enhances the prognostic significance of colorectal cancer infiltration by CD8⁺ T cells, suggesting that they might effectively promote antitumor immunity. Clin Cancer Res; 23(14); 3847-58. ©2017 AACR.

Davallia bilabiata exhibits anti-angiogenic effect with modified MMP-2/TIMP-2 secretion and inhibited VEGF ligand/receptors expression in vascular endothelial cells

ETHNOPHARMACOLOGICAL RELEVANCE

Davallia bilabiata Hosokawa (D. bilabiata), also called GuSuiBu, is popularly used as a substitute for Drynaria fortunei J. Sm for rheumatoid and degenerative arthritis in traditional Chinese medicine. Little is known about the underlying mechanisms of anti-angiogenesis responsible for arthritis in D. bilabiata which needs to be elucidated.

AIM OF THE STUDY

The present study is intended to investigate the anti-angiogenic effect of D. bilabiata associated with the modulation of matrix metalloproteinases (MMPs) and down regulation of vascular endothelial growth factor (VEGF) ligand/receptors both in vivo and in vitro.

MATERIALS AND METHODS

We investigated the potential anti-angiogenic effect of D. bilabiata by the in vivo neovascularization of chick chorioallantoic membranes (CAM) assay, and the in vitro migration and matrix-induced tube formation assay using human umbilical vascular endothelial cells (HUVECs). The expressions of MMP-2, TIMP-2, RECK and VEGF/VEGFR were analyzed by real-time RT-PCR or Western blot method.

RESULTS

One major compound from water extract of D. bilabiata was identified as Epicatechin 3-O-β-D-allopyranoside. D. bilabiata was confirmed to inhibit in vivo angiogenesis by CAM assay. D. bilabiata also exhibited in vitro anti-angiogenic and anti-regrowth effects as demonstrated by tube formation assay, transwell migration assay and wound healing assay. The mRNA expressions of MMP-2, and MMP-14 were decreased. On the contrary, tissue inhibitor of metalloproteinase-2 (TIMP-2), reversion-inducing cysteine-rich protein with kazal motifs (RECK) were increased by D. bilabiata. The extracellular MMP-2 activity was found to be reduced both in vitro and in vivo by D. bilabiata as determined by gelatin zymography. Results from western blot analysis and ELISA further demonstrated the decrease of MMP-2 and increase of TIMP-2 secretion after D. bilabiata treatment. The gene expressions of VEGF-A, -B, -C, -D and VEGFR-1, -2, -3 were all inhibited by D. bilabiata.

CONCLUSION

We concluded that the anti-angiogenic effect of D. bilabiata was associated with the decreased MMP-2 activity mediated by the upregulation of TIMP-2 and RECK, and the suppression of VEGF/VEGFRs expression.

The broad distribution of GP2 in mucous glands and secretory products

GP2, a GPI-anchored glycoprotein that is a useful marker for M cells of Peyer's patches, is functionally related to the uptake of pathogenic bacteria in the gut lumen. Our immunostaining throughout the whole body of mice detected a broader localization than previously found of GP2 in various mucous glands and secretory cells. In the oral cavity, the palatine gland and lingual gland intensely expressed GP2 with immunolabeling along the basolateral membrane of acini and in luminal secretions of ducts. Secretory portions of the duodenal gland as well as the pancreas were immunoreactive for GP2 in the digestive tract. Luminal contents in the small intestine contained aggregations of GP2-immunoreactive substances which mixed with bacteria. The bulbourethral gland of Cowper displayed the GP2 immunoreactivity among the male reproductive organs. The vaginal epithelium contained many GP2-immunoreactive goblet-like cells, the occurrence of which dramatically changed according to the estrous cycle. These findings show that GP2 is a popular secretory product released from mucous glands and secretory cells and may support defense mechanisms against pathogenic bacteria in the tubular organs open to the external milieu.

Mutations in HYAL2, Encoding Hyaluronidase 2, Cause a Syndrome of Orofacial Clefting and Cor Triatriatum Sinister in Humans and Mice

Orofacial clefting is amongst the most common of birth defects, with both genetic and environmental components. Although numerous studies have been undertaken to investigate the complexities of the genetic etiology of this heterogeneous condition, this factor remains incompletely understood. Here, we describe mutations in the HYAL2 gene as a cause of syndromic orofacial clefting. HYAL2, encoding hyaluronidase 2, degrades extracellular hyaluronan, a critical component of the developing heart and palatal shelf matrix. Transfection assays demonstrated that the gene mutations destabilize the molecule, dramatically reducing HYAL2 protein levels. Consistent with the clinical presentation in affected individuals, investigations of Hyal2-/- mice revealed craniofacial abnormalities, including submucosal cleft palate. In addition, cor triatriatum sinister and hearing loss, identified in a proportion of Hyal2-/- mice, were also found as incompletely penetrant features in affected humans. Taken together our findings identify a new genetic cause of orofacial clefting in humans and mice, and define the first molecular cause of human cor triatriatum sinister, illustrating the fundamental importance of HYAL2 and hyaluronan turnover for normal human and mouse development.

A novel TECTA mutation causes ARNSHL

OBJECTIVE

Autosomal recessive nonsyndromic hearing loss (ARNSHL) is a genetically heterogeneous sensorineural disorder. Alpha-tectorin, which is encoded by the TECTA gene, is a non-collagenous component of the tectorial membrane in the inner ear defect of which leads to moderate to severe hearing loss (HL).

METHODS

25 unrelated Iranian multiplex ARNSHL families, negative for GJB2 mutations, were recruited in this study. Clinical inspections including audiometric and otologic examinations ruled out syndromic forms. Genetic linkage analysis was performed using six short tandem repeat markers closely linked to DFNB21. Haplotype and LOD score analysis were used to confirm possible linkage. All coding exons of TECTA were subject to DNA sequencing in the linked family.

RESULTS

A novel homozygous variant (c.734G > A) was found in exon 5 of the TECTA gene in one family leading to a nonsense mutation (p.W245×). It co-segregated with HL in the family. This variant was not detected in 50 controls. All affected individuals in the family had moderate to severe HL. It full filled the criteria of a pathogenic variant.

CONCLUSION

Our data confirms the phenotype-directed genotyping for DFNB21 deafness against the typical profound HL phenotype seen in the most families segregating ARNSHL. We recommend mutation screening of TECTA in ARNSHL families segregating moderate to severe HL phenotype.

Proximal and distal regulation of the HYAL1 gene cluster by the estrogen receptor α in breast cancer cells

Chromosomal and genome abnormalities at the 3p21.3 locus are frequent events linked to epithelial cancers, including ovarian and breast cancers. Genes encoded in the 3p21.3 cluster include HYAL1, HYAL2 and HYAL3 members of hyaluronidases involved in the breakdown of hyaluronan, an abundant component of the vertebrate extracellular matrix. However, the transcriptional regulation of HYAL genes is poorly defined. Here, we identified the estrogen receptor ERα as a negative regulator of HYAL1 expression in breast cancer cells. Integrative data mining using METABRIC dataset revealed a significant inverse correlation between ERα and HYAL1 gene expression in human breast tumors. ChIP-Seq analysis identified several ERα binding sites within the 3p21.3 locus, supporting the role of estrogen as an upstream signal that diversely regulates the expression of 3p21.3 genes at both proximal and distal locations. Of these, HYAL1 was repressed by estrogen through ERα binding to a consensus estrogen response element (ERE) located in the proximal promoter of HYAL1 and flanked by an Sp1 binding site, required to achieve optimal estrogen repression. The repressive chromatin mark H3K27me3 was increased at the proximal HYAL1 ERE but not at other EREs contained in the cluster, providing a mechanism to selectively downregulate HYAL1. The HYAL1 repression was also specific to ERα and not to ERβ, whose expression did not correlate with HYAL1 in human breast tumors. This study identifies HYAL1 as an ERα target gene and provides a functional framework for the direct effect of estrogen on 3p21.3 genes in breast cancer cells.

The prion protein family member Shadoo induces spontaneous ionic currents in cultured cells

Some mutant forms of the cellular prion protein (PrPC) carrying artificial deletions or point mutations associated with familial human prion diseases are capable of inducing spontaneous ionic currents across the cell membrane, conferring hypersensitivity to certain antibiotics to a wide range of cultured cells and primary cerebellar granular neurons (CGNs). These effects are abrogated when the wild type (WT) form is co-expressed, suggesting that they might be related to a physiological activity of PrPC. Interestingly, the prion protein family member Shadoo (Sho) makes cells hypersensitive to the same antibiotics as mutant PrP-s, an effect that is diminished by the co-expression of WT-PrP. Here, we report that Sho engages in another mutant PrP-like activity: it spontaneously induces large ionic currents in cultured SH-SY5Y cells, as detected by whole-cell patch clamping. These currents are also decreased by the co-expression of WT-PrP. Furthermore, deletion of the N-terminal (RXXX)8 motif of Sho, mutation of the eight arginine residues of this motif to glutamines, or replacement of the hydrophobic domain by that of PrP, also diminish Sho-induced ionic currents. Our results suggest that the channel activity that is also characteristic to some pathogenic PrP mutants may be linked to a physiological function of Sho.

Cripto-1 modulates macrophage cytokine secretion and phagocytic activity via NF-κB signaling

Cripto-1 is an oncogenic protein belonging to the epidermal growth factor–Cripto-1/FRL-1/Cryptic family. It has important roles in tumor formation and metastasis, but its effects on the immune system are unclear. In the present study, we investigated the effects of Cripto-1 overexpression on macrophage activities and examined the underlying mechanisms. A cell line stably overexpressing Cripto-1 was developed. The culture supernatant from this cell line was collected and used to condition macrophages (RAW264.7, THP-1, and primary mouse macrophages) for various times. Exposure to this supernatant significantly increased the mRNA and protein expression levels of the anti-inflammatory cytokine interleukin (IL)-10 and of three pro-inflammatory cytokines (tumor necrosis factor-α, IL-6, and IL-1β), but did not affect the expression of transforming growth factor-β, another anti-inflammatory cytokine. Exposure to this supernatant also enhanced macrophage phagocytosis of chicken erythrocytes and yeast cells. Similar effects were observed in macrophages stimulated with purified Cripto-1 protein. Mechanistic experiments revealed that Cripto-1 activated nuclear factor (NF)-κB signaling by inducing IκB kinase phosphorylation and p65 nuclear translocation. Pretreatment with ammonium pyrrolidine dithiocarbamate, a specific NF-κB inhibitor, inhibited Cripto-1-induced cytokine secretion and phagocytosis of macrophages. Taken together, our present findings suggest that Cripto-1 enhances macrophage phagocytic activity and upregulates the production of anti- and pro-inflammatory cytokines via the NF-κB signaling pathway.

Identification of differential pathways in papillary thyroid carcinoma utilizing pathway co-expression analysis

PURPOSE

To identify differential pathways between papillary thyroid carcinoma (PTC) patients and normal controls utilizing a novel method which combined pathway with co-expression network.

METHODS

The proposed method included three steps. In the first step, we conducted pretreatments for background pathways and gained representative pathways in PTC. Subsequently, a co-expression network for representative pathways was constructed using empirical Bayes (EB) approach to assign a weight value for each pathway. Finally, random model was extracted to set the thresholds of identifying differential pathways.

RESULTS

We obtained 1267 representative pathways and their weight values based on the co-expressed pathway network, and then by meeting the criterion (Weight > 0.0296), 87 differential pathways in total across PTC patients and normal controls were identified. The top three ranked differential pathways were CREB phosphorylation, attachment of GPI anchor to urokinase plasminogen activator receptor (uPAR) and loss of function of SMAD2/3 in cancer.

CONCLUSIONS

In conclusion, we successfully identified differential pathways (such as CREB phosphorylation, attachment of GPI anchor to uPAR and post-translational modification: synthesis of GPI-anchored proteins) for PTC using the proposed pathway co-expression method, and these pathways might be potential biomarkers for target therapy and detection of PTC.

Monocytes/Macrophages Upregulate the Hyaluronidase HYAL1 and Adapt Its Subcellular Trafficking to Promote Extracellular Residency upon Differentiation into Osteoclasts

Osteoclasts are giant bone-resorbing cells originating from monocytes/macrophages. During their differentiation, they overexpress two lysosomal enzymes, cathepsin K and TRAP, which are secreted into the resorption lacuna, an acidified sealed area in contact with bone matrix where bone degradation takes place. Here we report that the acid hydrolase HYAL1, a hyaluronidase able to degrade the glycosaminoglycans hyaluronic acid (HA) and chondroitin sulfate, is also upregulated upon osteoclastogenesis. The mRNA expression and protein level of HYAL1 are markedly increased in osteoclasts differentiated from RAW264.7 mouse macrophages or primary mouse bone marrow monocytes compared to these precursor cells. As a result, the HYAL1-mediated HA hydrolysis ability of osteoclasts is strongly enhanced. Using subcellular fractionation, we demonstrate that HYAL1 proteins are sorted to the osteoclast lysosomes even though, in contrast to cathepsin K and TRAP, HYAL1 is poorly mannose 6-phosphorylated. We reported previously that macrophages secrete HYAL1 proforms by constitutive secretion, and that these are recaptured by the cell surface mannose receptor, processed in endosomes and sorted to lysosomes. Present work highlights that osteoclasts secrete HYAL1 in two ways, through lysosomal exocytosis and constitutive secretion, and that these cells promote the extracellular residency of HYAL1 through downregulation of the mannose receptor. Interestingly, the expression of the other main hyaluronidase, HYAL2, and of lysosomal exoglycosidases involved in HA degradation, does not increase similarly to HYAL1 upon osteoclastogenesis. Taken together, these findings point out the predominant involvement of HYAL1 in bone HA metabolism and perhaps bone remodeling via the resorption lacuna.

LY6E: a conductor of malignant tumor growth through modulation of the PTEN/PI3K/Akt/HIF-1 axis

Lymphocyte antigen 6 complex, locus E (LY6E) has been implicated in the malignant progression of various types of cancers; however, the underlying mechanism remains unclear. Here, we identified LY6E as an activator of HIF-1 and revealed their mechanistic and functional links in malignant tumor growth. The aberrant overexpression of LY6E increased HIF-1α gene expression principally at the transcription level. This, in turn, led to the expression of the pro-angiogenic factors, VEGFA and PDGFB, through decreases in the expression levels of PTEN mRNA and subsequent activation of the PI3K/Akt pathway. The LY6E-HIF-1 axis functioned to increase tumor blood vessel density and promoted tumor growth in immunodeficient mice. LY6E expression levels were significantly higher in human breast cancers than in normal breast tissues, and were strongly associated with the poor prognoses of various cancer patients. Our results characterized LY6E as a novel conductor of tumor growth through its modulation of the PTEN/PI3K/Akt/HIF-1 axis and demonstrated the validity of targeting this pathway for cancer therapy.

Characterization of Embryo Transcriptome of Gynogenetic Olive Flounder Paralichthys olivaceus

Olive flounder Paralichthys olivaceus is an important commercially cultured marine flatfish in China, Korea, and Japan. Gynogenesis, via meiogynogenesis and mitogynogenesis, shows advantages in breeding and sex control, but the low survival rate, especially for mitogynogenesis, limits its application. In this study, we sequenced the embryo transcriptomes of gynogenetic haploid, meiogynogenetic diploid, mitogynogenetic diploid, and common diploid flounder and investigated their respective genetic characteristics by analyzing differentiated expressed genes. Compared with common diploid, the gynogenetic haploid showed significant downregulation in notch signaling and wingless-related integration site (Wnt) signaling pathways, which may be the source of haploid syndrome. In both meiogynogenesis and mitogynogenesis, several upregulated genes including complement C3, formin-2, and intelectin may be related to increased survival compared to the haploid. The downregulation of immune system and energy metabolism-related genes caused retarded development of gynogenetic diploids compared with the common diploid. These data provided new and important information for application of artificially induced gynogenesis to aquaculture.

Expression Profile of Six RNA-Binding Proteins in Pulmonary Sarcoidosis

BACKGROUND

Sarcoidosis is characterised by up-regulation of cytokines and chemokine ligands/receptors and proteolytic enzymes. This pro-inflammatory profile is regulated post-transcriptionally by RNA-binding proteins (RBPs). We investigated in vivo expression of six RBPs (AUF1, HuR, NCL, TIA, TIAR, PCBP2) and two inhibitors of proteolytic enzymes (RECK, PTEN) in pulmonary sarcoidosis and compared it to the expression in four control groups of healthy individuals and patients with other respiratory diseases: chronic obstructive pulmonary disease (COPD), asthma and idiopathic interstitial pneumonias (IIPs).

METHODS

RT-PCR was used to quantify the mRNAs in bronchoalveolar (BA) cells obtained from 50 sarcoidosis patients, 23 healthy controls, 30 COPD, 19 asthmatic and 19 IIPs patients. Flow cytometry was used to assess intracellular protein expression of AUF1 and HuR in peripheral blood T lymphocytes (PBTLs) obtained from 9 sarcoidosis patients and 6 healthy controls.

RESULTS

Taking the stringent conditions for multiple comparisons into consideration, we consistently observed in the primary analysis including all patients regardless of smoking status as well as in the subsequent sub-analysis limited for never smokers that the BA mRNA expression of AUF1 (p<0.001), TIA (p<0.001), NCL (p<0.01) and RECK (p<0.05) was decreased in sarcoidosis compared to healthy controls. TIA mRNA was also decreased in sarcoidosis compared to both obstructive pulmonary diseases (COPD and asthma; p<0.001) but not compared to IIPs. There were several positive correlations between RECK mRNA and RBP mRNAs in BA cells. Also sarcoidosis CD3+, CD4+ and CD8+ PBTLs displayed lower mean fluorescence intensity of AUF1 (p≤0.02) and HuR (p≤0.03) proteins than control healthy PBTLs.

CONCLUSION

mRNA expressions of three RBPs (AUF1, TIA and NCL) and their potential target mRNA encoding RECK in BA cells and additionally protein expression of AUF1 and HuR in PBTLs were down-regulated in our sarcoidosis patients compared to healthy individuals. Its significance, e.g. for stability of mRNAs encoding pro-inflammatory factors, should be further explored in sarcoidosis.

MicroRNA-15b regulates reversion-inducing cysteine-rich protein with Kazal motifs (RECK) expression in human uterine leiomyoma

BACKGROUND

Human uterine leiomyoma (fibroids; LYO) are the most common benign neoplasms in reproductive-aged women. Dysregulated extracellular matrix and irregular LYO reversion-inducing cysteine-rich protein with Kazal motifs (RECK) expression are thought to be mediated by aberrant microRNA (miR) expression. The relationship of miR-15b and RECK expression in LYO has not been studied.

METHODS

The expression levels of miR-15b and RECK were determined by quantitative RT-PCR, Western blot, and immunohistochemistry in cultures derived from commercial primary leiomyoma (cpLYO) and myometrial (cpMYO) cell lines and leiomyoma (pLYO) and myometrium (pMYO) tissue from surgical samples respectively. The relationship between miR-15b and RECK expression in cpLYO and pLYO (compared to their respective myometrial controls) was evaluated following transfection of cell cultures with either miR-15b mimic or inhibitor.

RESULTS

Elevated levels of miR-15b were observed in cpLYO (2.82-fold; p = 0.04) and pLYO cell (1.30-fold; p = 0.0001) cultures respectively compared to corresponding MYO cell controls. Following transfection with miR-15b mimic, cpLYO cells (0.62-fold; p < 0.0001) and pLYO cells (0.68-fold; p < 0.0001) demonstrated reduced RECK protein expression. Following transfection with miR-15b inhibitor, cpLYO cells (1.20-fold; p < 0.0001) and pLYO cells (1.31-fold; p = 0.0007) demonstrated elevated RECK protein expression. RECK protein expression was reduced in pLYO tissues (0.73-fold; p < 0.0001) and pLYO (0.47-fold; p = 0.047) cells when compared to the corresponding MYO tissue controls.

CONCLUSION

Our findings suggest that miR-15b negatively regulates RECK expression in LYO, and increased miR-15b and decreased RECK expression may contribute to the pathobiology of LYO. The functional significance of miR-15b and RECK expression warrants further investigation as potential therapeutic targets for the treatment of human LYO.