Epithelial-mesenchymal Interactions Research Articles

Sculpting the skull through neurosensory epithelial-mesenchymal signaling.

The vertebrate skull is a complex structure housing the brain and specialized sensory organs, including the eye, the inner ear, and the olfactory system. The close association between bones of the skull and the sensory organs they encase has posed interesting developmental questions about how the tissues scale with one another. Mechanisms that regulate morphogenesis of the skull are hypothesized to originate in part from the encased neurosensory organs. Conversely, the developing skull is hypothesized to regulate the growth of neurosensory organs, through mechanical forces or molecular signaling. Here, we review studies of epithelial-mesenchymal interactions during inner ear and olfactory system development that may coordinate the growth of the two sensory organs with their surrounding bone. We highlight recent progress in the field and provide evidence that mechanical forces arising from bone growth may affect olfactory epithelium development. Developmental Dynamics 248:88-97, 2019. © 2018 Wiley Periodicals, Inc.

The localization and distribution of cells labeled by a somatic stem cell-recognizing antibody (A3) in rat colon development; possible presence of a new cell type forming the intestinal stem cell niche.

A3, generated as a monoclonal antibody against rat malignant fibrous histiocytoma (MFH)-derived cloned cells, recognizes somatic stem cells (bone-marrow/hair follicle stem cells). We investigated the distribution of cells immunoreactive to A3 in the developing rat intestine (particularly, the colon), focusing on the ontogenic kinetics of A3-positive cells. In the rat intestine, A3 labeled spindle-shaped stromal cells localized in the submucosa and labeled endothelial cells of capillaries in the lamina propria forming villi in the early development stage. With development progression, A3-positive cells were exclusively localized around the crypts of the colon. Double immunofluorescence revealed that A3-positive cells around the crypts reacted to vimentin (for mesenchymal cells) and Thy-1 (for mesenchymal stromal cells) but not to α-SMA (for mesenchymal myofibroblastic cells) or CD34 (for hematopoietic stem cells), indicating that A3-positive cells around the crypts may have characteristics of immature mesenchymal cells. In addition, A3 labeled a few epithelial cells at the base of colon crypts. Furthermore, immunoelectron microscopy revealed that A3-positive cells lay inside myofibroblasts adjacent to the epithelium of the crypts. A3-positive cells were regarded as a new type of immature mesenchymal cells around the crypts. Collectively, A3-positive cells might take part in the stem cell niche in the colon, which is formed through epithelial-mesenchymal interaction.

Development of the human bladder and ureterovesical junction

The urinary bladder collects urine from the kidneys and stores it until the appropriate moment for voiding. The trigone and ureterovesical junctions are key to bladder function, by allowing one-way passage of urine into the bladder without obstruction. Embryological development of these structures has been studied in multiple animal models as well as humans. In this report we review the existing literature on bladder development and cellular signalling with particular focus on bladder development in humans.The bladder and ureterovesical junction form primarily during the fourth to eighth weeks of gestation, and arise from the primitive urogenital sinus following subdivision of the cloaca. The bladder develops through mesenchymal-epithelial interactions between the endoderm of the urogenital sinus and mesodermal mesenchyme. Key signalling factors in bladder development include shh, TGF-β, Bmp4, and Fgfr2. A concentration gradient of shh is particularly important in development of bladder musculature, which is vital to bladder function. The ureterovesical junction forms from the interaction between the Wolffian duct and the bladder. The ureteric bud arises from the Wolffian duct and is incorporated into the developing bladder at the trigone. It was previously thought that the trigonal musculature developed primarily from the Wolffian duct, but it has been shown to develop primarily from bladder mesenchyme. Following emergence of the ureters from the Wolffian ducts, extensive epithelial remodelling brings the ureters to their final trigonal positions via vitamin A-induced apoptosis. Perturbation of this process is implicated in clinical obstruction or urine reflux. Congenital malformations include ureteric duplication and bladder exstrophy.

FOXF1 transcription factor promotes lung morphogenesis by inducing cellular proliferation in fetal lung mesenchyme

Organogenesis is regulated by mesenchymal-epithelial signaling events that induce expression of cell-type specific transcription factors critical for cellular proliferation, differentiation and appropriate tissue patterning. While mesenchymal transcription factors play a key role in mesenchymal-epithelial interactions, transcriptional networks in septum transversum and splanchnic mesenchyme remain poorly characterized. Forkhead Box F1 (FOXF1) transcription factor is expressed in mesenchymal cell lineages; however, its role in organogenesis remains uncharacterized due to early embryonic lethality of Foxf1-/- mice. In the present study, we generated mesenchyme-specific Foxf1 knockout mice (Dermo1-Cre Foxf1-/-) and demonstrated that FOXF1 is required for development of respiratory, cardiovascular and gastrointestinal organ systems. Deletion of Foxf1 from mesenchyme caused embryonic lethality in the middle of gestation due to multiple developmental defects in the heart, lung, liver and esophagus. Deletion of Foxf1 inhibited mesenchyme proliferation and delayed branching lung morphogenesis. Gene expression profiling of micro-dissected distal lung mesenchyme and ChIP sequencing of fetal lung tissue identified multiple target genes activated by FOXF1, including Wnt2, Wnt11, Wnt5A and Hoxb7. FOXF1 decreased expression of the Wnt inhibitor Wif1 through direct transcriptional repression. Furthermore, using a global Foxf1 knockout mouse line (Foxf1-/-) we demonstrated that FOXF1-deficiency disrupts the formation of the lung bud in foregut tissue explants. Finally, deletion of Foxf1 from smooth muscle cell lineage (smMHC-Cre Foxf1-/-) caused hyper-extension of esophagus and trachea, loss of tracheal and esophageal muscle, mispatterning of esophageal epithelium and decreased proliferation of smooth muscle cells. Altogether, FOXF1 promotes lung morphogenesis by regulating mesenchymal-epithelial signaling and stimulating cellular proliferation in fetal lung mesenchyme.

TGF-β Signaling in Lung Health and Disease.

Transforming growth factor (TGF)-β is an evolutionarily conserved pleiotropic factor that regulates a myriad of biological processes including development, tissue regeneration, immune responses, and tumorigenesis. TGF-β is necessary for lung organogenesis and homeostasis as evidenced by genetically engineered mouse models. TGF-β is crucial for epithelial-mesenchymal interactions during lung branching morphogenesis and alveolarization. Expression and activation of the three TGF-β ligand isoforms in the lungs are temporally and spatially regulated by multiple mechanisms. The lungs are structurally exposed to extrinsic stimuli and pathogens, and are susceptible to inflammation, allergic reactions, and carcinogenesis. Upregulation of TGF-β ligands is observed in major pulmonary diseases, including pulmonary fibrosis, emphysema, bronchial asthma, and lung cancer. TGF-β regulates multiple cellular processes such as growth suppression of epithelial cells, alveolar epithelial cell differentiation, fibroblast activation, and extracellular matrix organization. These effects are closely associated with tissue remodeling in pulmonary fibrosis and emphysema. TGF-β is also central to T cell homeostasis and is deeply involved in asthmatic airway inflammation. TGF-β is the most potent inducer of epithelial-mesenchymal transition in non-small cell lung cancer cells and is pivotal to the development of tumor-promoting microenvironment in the lung cancer tissue. This review summarizes and integrates the current knowledge of TGF-β signaling relevant to lung health and disease.

Human esophageal myofibroblast secretion of bone morphogenetic proteins and GREMLIN1 and paracrine regulation of squamous epithelial growth

We have previously shown myofibroblasts subjacent to the squamous epithelium in the normal human esophagus and an increase in esophagitis. Myofibroblast contribution to bone morphogenetic protein (BMP) signaling and to paracrine mediated epithelial-mesenchymal interactions in the human esophagus remains incompletely defined. We investigated BMP4 and BMP inhibitor GREM1 gene expression and protein levels in previously characterized human esophageal myofibroblast primary cultures and in a human esophageal myofibroblast cell line. We adapted human esophageal myofibroblast conditioned media into a 3D organotypic model to investigate the effect of myofibroblast secreted factors on squamous epithelial morphology, proliferation, differentiation and BMP signaling. Human esophageal myofibroblasts constitutively secrete GREM1 and increase BMP4 expression and BMP4 secretion in response to epithelial Hedgehog ligand SHH. Detection of secreted BMP4 is decreased in the presence of GREM1. Myofibroblast conditioned media increases epithelial proliferation and expression of basal markers p63 and CK14 leading to an overall increase in epithelial thickness. Epithelial BMP signaling increases with myofibroblast conditioned media. These findings were partially reversed with GREM1 inhibition. Our results demonstrate that myofibroblasts are potential sources of GREM1 and of BMP4 in the human esophagus and that human esophageal myofibroblast-epithelial paracrine interactions contribute in part to the regulation of epithelial growth.

Ectopic Hedgehog Signaling Causes Cleft Palate and Defective Osteogenesis

Cleft palate is a common birth defect that frequently occurs in human congenital malformations caused by mutations in components of the Sonic Hedgehog (SHH) signaling cascade. Shh is expressed in dynamic, spatiotemporal domains within epithelial rugae and plays a key role in driving epithelial-mesenchymal interactions that are central to development of the secondary palate. However, the gene regulatory networks downstream of Hedgehog (Hh) signaling are incompletely characterized. Here, we show that ectopic Hh signaling in the palatal mesenchyme disrupts oral-nasal patterning of the neural crest cell–derived ectomesenchyme of the palatal shelves, leading to defective palatine bone formation and fully penetrant cleft palate. We show that a series of Fox transcription factors, including the novel direct target Foxl1, function downstream of Hh signaling in the secondary palate. Furthermore, we demonstrate that Wnt/bone morphogenetic protein (BMP) antagonists, in particular Sostdc1, are positively regulated by Hh signaling, concomitant with downregulation of key regulators of osteogenesis and BMP signaling effectors. Our data demonstrate that ectopic Hh-Smo signaling downregulates Wnt/BMP pathways, at least in part by upregulating Sostdc1, resulting in cleft palate and defective osteogenesis.

Gene profiling involved in fate determination of salivary gland type in mouse embryogenesis.

Salivary gland (SG) development involves dynamic epithelial-mesenchymal interactions resulting in the formation of highly branched epithelial structures that produce and secrete saliva. The SG epithelium differentiates into saliva-producing terminal buds, i.e., acini, and transporting ducts. Most studies on the salivary gland have focused on branching morphogenesis; however, acinar cell differentiation underlying the determination of serous or mucous salivary glands is unclear. The objective of this study was to identify the mesenchymal signaling molecules involved in the epithelial differentiation of the salivary gland type as serous or mucous. Salivary glands undergoing stage-specific development, including the parotid gland (PG) and the sublingual gland (SLG) at embryonic day 14.5 (E14.5) were dissected. The glands were treated with dispase II to separate the epithelium and the mesenchyme. RNA from mesenchyme was processed for microarray analysis. Thereafter, microarray data were analyzed to identify putative candidate molecules involved in salivary gland differentiation and confirmed via quantitative reverse transcription polymerase chain reaction. The microarray analysis revealed the expression of 31,873 genes in the PG and SLG mesenchyme. Of the expressed genes 21,026 genes were found to be equally expressed (Fold change 1.000) in both PG and SLG mesenchyme. The numbers of genes expressed over onefold in the PG and SLG mesenchyme were found to be 5247 and 5600 respectively. On limiting the fold-change cut off value over 1.5 folds, only 214 and 137 genes were expressed over 1.5 folds in the PG and the SLG mesenchyme respectively. Our findings suggest that differential expression patterns of the mesenchymal signaling molecules are involved in fate determination of the salivary acinar cell types during mouse embryogenesis. In the near future, functional evaluation of the candidate genes will be performed using gain- and loss-of-function mutation studies during in vitro organ cultivation.

Nephronectin (NPNT) and the prediction of nephrotic syndrome response to steroid treatment.

Steroid-resistant nephrotic syndrome represents about 10-20% of pediatrics' nephrotic syndrome. The regeneration of glomerular barrier seems pivotal for cessation of proteinuria. Nephronectin (NPNT) plays a major role in nephrogenesis, signal transduction, and epithelial-mesenchymal interactions. This study aims to preliminary assess NPNT as potential noninvasive biomarker of glomerular regeneration and its ability to identify steroid resistance. In this case control study, 80 retrospectively selected patients with nephrotic syndrome were enrolled in addition to 40 healthy controls. Forty patients were steroid sensitive (SSNS) and the other 40 patients were steroid-resistant (SRNS), NPTN concentration was measured using ELISA and NPNT mRNA expression was assayed using real-time PCR. NPTN concentrations were significantly higher in SSNS than both SRNS and controls (The means were 4.64 ± 3.05, 0.69 ± 0.44, and 1.63 ± 0.59, respectively). Moreover, NPTN concentrations were significantly lower in SRNS than controls. NPTN was significantly overexpressed in SSNS compared to both SRNS and controls (the means were 10.82 ± 7.39, 1.19 ± 0.94, and 1.04 ± 0.10, respectively) with no statistically significant difference between SRNS and controls. ROC curves analysis showed that both NPNT expression and NPNT serum level are of promising diagnostic performance (ROCAUC 0.948 and 0.896, respectively). Regression analysis showed that both NPNT expression and NPNT serum level can be independent predictors of steroid resistance. The present study shows for the first time an enhanced expression of NPNT in steroid-sensitive nephrotic syndrome patients suggesting NPNT as a marker of glomerular regeneration. Also, serum NPNT can be a useful noninvasive biomarker of steroid resistance.

Tissue interactions and estrogenic response during human female fetal reproductive tract development

The role of tissue interactions was explored to determine whether epithelial differentiation within the developing human reproductive tract is induced and specified by mesenchyme in tissue recombinants composed of mouse vaginal mesenchyme + human uterine tubal epithelium (mVgM+hTubE). The tissue recombinants were grown in DES-treated ovariectomized athymic mice. After 2–4 weeks of in vivo growth, several vaginal specific features were expressed in the human tubal epithelium. The mesenchyme-induced effects included morphological change as well as expression of several immunohistochemical markers. Although the mesenchyme-induced shift in vaginal differentiation in the human tubal epithelium was not complete, the partial induction of vaginal markers in human tubal epithelium verifies the importance of mesenchymal-epithelial interactions in development of the human female reproductive tract.In a separate experiment, DES-induction of uterine epithelial progesterone receptor (PGR) and estrogen receptor 1 (ESR1) was explored in tissue recombinants composed of wild-type or Esr1KO mouse uterine mesenchyme + human fetal uterine epithelium (wt UtM+hUtE and Esr1KO UtM+hUtE). The rationale of this experiment was to determine whether DES-induction of PGR and ESR1 is mediated directly via epithelial ESR1 or indirectly (paracrine mechanism) via mesenchymal ESR1. DES-induction of uterine epithelial ESR1 and PGR in Esr1KO UtM+hUtE tissue recombinants (devoid of mesenchymal ESR1) formally eliminates the paracrine mechanism and demonstrates that DES induction of human uterine epithelial ESR1 and PGR is directly mediated via epithelial ESR1.

Counter-rotational cell flows drive morphological and cell fate asymmetries in mammalian hair follicles.

Organ morphogenesis is a complex process coordinated by cell specification, epithelial-mesenchymal interactions, and tissue polarity. A striking example is the pattern of regularly spaced, globally aligned mammalian hair follicles, which emerges through epidermal-dermal signaling and planar polarized morphogenesis. Here, using live-imaging, we discover that developing hair follicles polarize through dramatic cell rearrangements organized in a counter-rotational pattern of cell flows. Upon hair placode induction, Shh signaling specifies a radial pattern of progenitor fates that, together with planar cell polarity (PCP), induce counter-rotational rearrangements through myosin and ROCK-dependent polarized neighbor exchanges. Importantly, these cell rearrangements also establish cell fate asymmetry by repositioning radial progenitors along the anterior-posterior axis. These movements concurrently displace associated mesenchymal cells, which then signal asymmetrically to maintain polarized cell fates. Our results demonstrate how spatial patterning and tissue polarity generate an unexpected collective cell behavior that in turn, establishes both morphological and cell fate asymmetry.

Comparative gene expression profiles of dental follicle at different stages of periodontal development: Combined use of laser capture microdissection and microarray

ObjectivesOdontogenesis is dependent on serial temporal and spatial epithelial-mesenchymal interaction. Multiple signaling networks have been identified in the inductive interactions of odontogenesis at the early stage. Technical obstacles and heterogeneity of the dental follicle (DF), which is the origin of the majority of periodontal tissues, have hindered the clarification of the molecular blueprint in early periodontal tissue development. This has in turn hindered studies of new/effective periodontal regeneration therapy. In this study, we comparatively analyzed the gene expression profiles of DF at E17 (when DF cells are histologically recognized) and PN2 (the initiation of periodontal development). MethodsGene expression profiles of DF at E17 and PN2 were assessed by the combined use of laser capture microdissection and microarray. ResultsComparative gene expression analysis of DF at E17 and PN2 during periodontal development revealed > 2-fold up-regulation and down-regulation of 2519 and 5060 genes, respectively. Bioinformatic analysis of the selected genes revealed that the temporally changed genes were mostly enriched in GO terms relative to the vasculature system, and were sometimes linked to multiple processes. RT-qPCR was used to verify the microarray data. ConclusionsThe delineation of the differential gene expressions between pre- and post-natal developmental stages of DF in vivo will increase the understanding of periodontal tissue development.

Bone Morphogenetic Protein 2 Coordinates Early Tooth Mineralization

Formation of highly organized dental hard tissues is a complex process involving sequential and ordered deposition of an extracellular scaffold, followed by its mineralization. Odontoblast and ameloblast differentiation involves reciprocal and sequential epithelial-mesenchymal interactions. Similar to early tooth development, various Bmps are expressed during this process, although their functions have not been explored in detail. Here, we investigated the role of odontoblast-derived Bmp2 for tooth mineralization using Bmp2 conditional knockout mice. In developing molars, Bmp2LacZ reporter mice revealed restricted expression of Bmp2 in early polarized and functional odontoblasts while it was not expressed in mature odontoblasts. Loss of Bmp2 in neural crest cells, which includes all dental mesenchyme, caused a delay in dentin and enamel deposition. Immunohistochemistry for nestin and dentin sialoprotein (Dsp) revealed polarization defects in odontoblasts, indicative of a role for Bmp2 in odontoblast organization. Surprisingly, pSmad1/5/8, an indicator of Bmp signaling, was predominantly reduced in ameloblasts, with reduced expression of amelogenin (Amlx), ameloblastin (Ambn), and matrix metalloproteinase (Mmp20). Quantitative real-time polymerase chain reaction (RT-qPCR) analysis and immunohistochemistry showed that loss of Bmp2 resulted in increased expression of the Wnt antagonists dickkopf 1 (Dkk1) in the epithelium and sclerostin (Sost) in mesenchyme and epithelium. Odontoblasts showed reduced Wnt signaling, which is important for odontoblast differentiation, and a strong reduction in dentin sialophosphoprotein (Dspp) but not collagen 1 a1 (Col1a1) expression. Mature Bmp2-deficient teeth, which were obtained by transplanting tooth germs from Bmp2-deficient embryos under a kidney capsule, showed a dentinogenesis imperfecta type II–like appearance. Micro–computed tomography and scanning electron microscopy revealed reduced dentin and enamel thickness, indistinguishable primary and secondary dentin, and deposition of ectopic osteodentin. This establishes that Bmp2 provides an early temporal, nonredundant signal for directed and organized tooth mineralization.

Differential tissue growth and cell adhesion alone drive early tooth morphogenesis: An ex vivo and in silico study.

From gastrulation to late organogenesis animal development involves many genetic and bio-mechanical interactions between epithelial and mesenchymal tissues. Ectodermal organs, such as hairs, feathers and teeth are well studied examples of organs whose development is based on epithelial-mesenchymal interactions. These develop from a similar primordium through an epithelial folding and its interaction with the mesenchyme. Despite extensive knowledge on the molecular pathways involved, little is known about the role of bio-mechanical processes in the morphogenesis of these organs. We propose a simple computational model for the biomechanics of one such organ, the tooth, and contrast its predictions against cell-tracking experiments, mechanical relaxation experiments and the observed tooth shape changes over developmental time. We found that two biomechanical processes, differential tissue growth and differential cell adhesion, were enough, in the model, for the development of the 3D morphology of the early tooth germ. This was largely determined by the length and direction of growth of the cervical loops, lateral folds of the enamel epithelium. The formation of these cervical loops was found to require accelerated epithelial growth relative to other tissues and their direction of growth depended on specific differential adhesion between the three tooth tissues. These two processes and geometrical constraints in early tooth bud also explained the shape asymmetry between the lateral cervical loops and those forming in the anterior and posterior of the tooth. By performing mechanical perturbations ex vivo and in silico we inferred the distribution and direction of tensile stresses in the mesenchyme that restricted cervical loop lateral growth and forced them to grow downwards. Overall our study suggests detailed quantitative explanations for how bio-mechanical processes lead to specific morphological 3D changes over developmental time.

Skin and scale regeneration after mechanical damage in a teleost

Skin wound healing has been widely studied in mammalian models but the information on teleost cutaneous healing is sparse and frequently considered in the context of viral or bacterial infections or parasitic infestations in aquaculture. In the present study a detailed time course (0 h, 6 h, 1, 2, 3 and 4 days) coupled to morphology and gene expression analysis revealed rapid regeneration of skin without scarring in a marine teleost after a superficial wound caused by the loss of a large area of scales. The integrity of the integument, as assessed by quantification of extracellular matrix (ECM) gene transcripts (fn1a, colIα1, colVα2, colXα1, ogn1, ogn2, crtac1a, cyr61, pcna, krt2 and mmp9) was restored within 2 days. Epithelial-mesenchyme interactions assessed by expression of edar and shh were associated with epidermal closure, the re-establishment of the basement membrane and also scale eruption. Histological observations suggested tissue re-epithelialization was independent of inflammation and that transcripts representing the humoral and cellular elements of the immune response (mpo, cyba and csf1r, cd48 and cd200) were modulated in the early stages of sea bream (Sparus aurata) skin repair after injury. Overall, the results indicate that after superficial skin damage tissue reconstitution started immediately with re-epithelialization, followed by ECM deposition and finally tissue maturation, indicating that in the skin regenerative process, reconstitution of the physical barrier was the priority over other integument functions, including immune surveillance.

Regulatory mechanisms of branching morphogenesis in mouse submandibular gland rudiments.

SummaryBranching morphogenesis is an important developmental process for many organs, including the salivary glands. Whereas epithelial–mesenchymal interactions, which are cell-to-cell communications, are known to drive branching morphogenesis, the molecular mechanisms responsible for those inductive interactions are still largely unknown. Cell growth factors and integrins are known to be regulators of branching morphogenesis of salivary glands. In addition, functional microRNAs (miRNAs) have recently been reported to be present in the developing submandibular gland. In this review, the authors describe the roles of various cell growth factors, integrins and miRNAs in branching morphogenesis of developmental mouse submandibular glands.

Gelatinases A and B and their endogenous regulators in the corpus uteri in squamous cell cervical carcinoma

To investigate the expression of gelatinases A and B (matrix metalloproteinases (MMP 2 and MMP 9) and endogenous regulators of their activity, such as a tissue inhibitor of MMP - TIMP-2 and a Pro-MMP-9 activator - urokinase-type plasminogen activator (uPA) as factors of corpus uteri invasion in squamous cell cervical carcinoma (SCCC). The surgical material obtained after hysterectomy in patients diagnosed with SCCC was examined. RT-PCR, immunohistochemistry (IHC), and enzyme-linked immunosorbent assay were used. In SCCC, the expressions of MMP 2 and MMP 9 were found to be high not only in carcinoma of the cervix uteri but also in the corpus uteri, which makes an additional contribution to the enhanced invasive potential of tumors and may have a prognostic value. In SCCC, the expression of MMP 9 may be induced in the corpus uteri where it was absent in normal conditions. MMP 9 can serve as a marker of an invasive process. In most cases, the activity of uPA in the tumor was significantly higher than that in intact uterine tissue, and the expression of TIMP-2 did not change substantially along the entire length of a tissue band (from the vaginal wall to the uterine fundus), as evidenced by RT-PCR, and was at a low level or absent, as shown by IHC. Impaired regulation of MMP 2 and MMP 9 expressions was found not only at the gene level, but also at post-translational one. The expression of the gelatinases MMP 2, MMP 9 and regulators of their activity is aimed at increasing the tumor destructive (invasive) potential and can occur (be induced) in the intact corpus uteri tissue that is morphologically different from cervix uteri tissue with apparent participation of signaling through an epithelial-mesenchymal interaction. The induced MMP 9 can serve as a marker for invasive potential. The data indicate different tissue functions of MMP 2 and MMP 9. They are important for understanding the role of the gelatinases MMP 2, MMP 9 during carcinogenesis, can have a prognostic value, and affect a therapeutic strategy for patient management.

LncRNA PVT1 promotes ovarian cancer progression by silencing miR-214.

Objective:Emerging evidence indicates that long non-coding RNAs (lncRNAs) are critical in carcinogenesis and progression of ovarian cancer. This study aimed to explore the functions and molecular mechanisms of plasmacytoma variant translocation I (PVT1) in ovarian cancerMethods:PVT1 and miR-214 were detected by qRT-PCR assays in ovarian cancer tissues and cells. The cell proliferation, migration, and invasion abilities were detected by cell functional experiments, respectively. Western blot assay was performed to detect epithelial-mesenchymal transition (EMT) markers. MiR-214 expression regulated by PVT1 was studied by RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assays.Results:The expression of PVT1 was up-regulated in ovarian cancer tissues and cell lines. Elevated PVT1 expression was associated with advanced stage and indicated poor prognosis for ovarian cancer patients. The knockdown of PVT1 impaired SKOV3 cell proliferation, migration, and invasion in vitro. The promotion of ovarian cancer progression by PVT1 involved in regulation of the epithelial-mesenchymal transition process and PVT1 interaction with EZH2 represses miR-214 expression in ovarian cancer cells. Conclusions:PVT1 plays an important role in ovarian cancer tumorigenesis, which might be as a novel diagnostic marker and therapeutic target for ovarian cancer.

Role of hypoxia in malignant transformation of oral submucous fibrosis

Context: In the Indian subcontinent and Southeast Asia, habit of chewing areca nut has been recognized as one of the most important risk factors leading to a ubiquitous oral potentially malignant disorder (OPMD), oral submucous fibrosis (OSMF).In OSMF, owing to fibrosis in the connective tissue, there is narrowing of blood vessels which further results in compromised blood supply to the local tissue milieu. This tissue hypoxia elicits the activation of the transcription factor Hypoxia-inducible factor 1-alpha (HIF-1 α). In OSMF, its expression shows significant correlation with degree of epithelial dysplasia. Aim: This study aims to evaluate the expression of HIF-1 α in OSMF. Settings and Design: Seventy-five histopathologically proven cases of OSMF were included in the study. The tissue sections were studied for histopathological evaluation and HIF-1α expression. Statistical Analysis Used: Descriptive and inferential statistics using one-way ANOVA and multiple comparison using Kruskal–Wallis test were used. Results: Comparison of HIF-1α expression in different grades of OSMF was done. There were 47 cases without dysplasia, whereas 16 and 12 were of low-risk and high-risk dysplasia, respectively. On comparison of HIF-1α expression in different grades of OSMF, it was found to increase significantly from normal oral mucosa (1.43 ± 0.89) to no dysplasia (3.97 ± 2.75) to low-risk epithelial dysplasia (4.93 ± 1.76) to high-risk epithelial dysplasia (5.66 ± 2.01). Conclusion: The altered expression of HIF-1α can signify the disturbed epithelial-mesenchymal interaction which indicates progression toward the malignant transformation of OSMF. Thus, HIF-1 α expression showed good correlation with increase in grades of epithelial dysplasia and thus can assist for grading/quantifying oral epithelial dysplasia in OSMF.

Evolutionary recruitment of flexible Esrp-dependent splicing programs into diverse embryonic morphogenetic processes

Epithelial-mesenchymal interactions are crucial for the development of numerous animal structures. Thus, unraveling how molecular tools are recruited in different lineages to control interplays between these tissues is key to understanding morphogenetic evolution. Here, we study Esrp genes, which regulate extensive splicing programs and are essential for mammalian organogenesis. We find that Esrp homologs have been independently recruited for the development of multiple structures across deuterostomes. Although Esrp is involved in a wide variety of ontogenetic processes, our results suggest ancient roles in non-neural ectoderm and regulating specific mesenchymal-to-epithelial transitions in deuterostome ancestors. However, consistent with the extensive rewiring of Esrp-dependent splicing programs between phyla, most developmental defects observed in vertebrate mutants are related to other types of morphogenetic processes. This is likely connected to the origin of an event in Fgfr, which was recruited as an Esrp target in stem chordates and subsequently co-opted into the development of many novel traits in vertebrates.