Inherited cataracts: molecular genetics, clinical features, disease mechanisms and novel therapeutic approaches

Cataract is the most common cause of blindness in the world; during infancy and early childhood, it frequently results in visual impairment. Congenital cataracts are phenotypically and genotypically heterogeneous and can occur in isolation or in association with other systemic disorders. Significant progress has been made in identifying the molecular genetic basis of cataract; 115 genes to date have been found to be associated with syndromic and non-syndromic cataract and 38 disease-causing genes have been identified to date to be associated with isolated cataract. In this review, we briefly discuss lens development and cataractogenesis, detail the variable cataract phenotypes and molecular mechanisms, including genotype-phenotype correlations, and explore future novel therapeutic avenues including cellular therapies and pharmacological treatments.

CEREBRAL ORGANOIDS AS A MODEL FOR GLIOBLASTOMA MULTIFORME

Glioblastoma multiforme (GBM) is a highly lethal and elusive cancer. While many in vitro and in vivo models have been developed to recapitulate the factors that contribute to its invasive behavior, they suffer from drawbacks related to genetic variability, expense and scope. Technologies utilizing human pluripotent stem cells can now generate organoids which can recapitulate the relative complexity the cytoarchitecture and microenvironment of human brain tissue. In conjunction with protocols which effectively induce GBM tumors within these "cerebral organoids", such approaches represent an unprecedented model to investigate GBM invasion and its effect on the brain ECM. This review focuses on methods of brain organoid development, protocols for inducing GBM, the relevant findings on invasion and microenvironmental changes, and discusses their limitations and potential future direction.

MicroRNAs in combined spent culture media and sperm are associated with embryo quality and pregnancy outcome

OBJECTIVE

To identify differentially abundant miRNAs in sperm samples and spent culture media (SCM) of embryos of different grade toward a prediction of pregnancy outcome.

DESIGN

Array-based reverse-transcription quantitative polymerase chain reaction profiling and validation.

SETTING

University research institute and in vitro fertilization center.

PATIENT(S)

Couples (n = 61) undergoing infertility treatment with the use of intracytoplasmic sperm injection.

INTERVENTIONS(S)

None.

MAIN OUTCOME MEASURE(S)

Abundance levels of miRNAs in combined SCM of embryos of different quality and in sperm samples associated with pregnancy outcome.

RESULT(S)

Out of 372 screened miRNAs, miR-19b-3p and let-7a-5p were detected consistently in all SCM and sperm samples. The abundance levels of miRNAs were significantly altered between SCM of embryos with different quality (G1, G2, and G3 grades). Specifically, miR-320a and miR-15a-5p were differentially abundant in G1 vs. G2, miR-21-5p in G1 vs. G3, and miR-20a-5p in G2 vs. G3. The abundance levels of combined SCM and sperm derived miRNAs were also significantly altered between different pregnancy outcomes. MiR-19b-3p showed the highest area under the receiver operating characteristic curve values between positive and negative outcomes, with lower abundance levels in both combined SCM and sperm samples associated with a positive pregnancy outcome. MiR-320a, miR-15a-5p, miR-21-5p, and miR-20a-5p showed similar results in combined SCM samples.

CONCLUSION(S)

miRNA abundance levels in combined SCM and sperm differed significantly depending on embryo quality and pregnancy outcome. MiR-19b-3p may serve as a potential biomarker to predict pregnancy outcome.

Macrocyclic peptides that inhibit Wnt signalling via interaction with Wnt3a

Here we report de novo macrocyclic peptide binders to Wnt3a, a member of the Wnt protein family. By means of the Random non-standard Peptides Integrated Discovery (RaPID) system, we have performed in vitro selection against the complex of mouse Wnt3a (mWnt3a) with human afamin (hAFM) to discover macrocyclic peptides that bind mWnt3a with K _D values as tight as 110 nM. One of these peptides, WAp-D04 (Wnt-AFM-peptide-D04), was able to inhibit the receptor-mediated signaling process, which was demonstrated in a Wnt3a-dependent reporter cell-line. Based on this initial hit, we applied a block-mutagenesis scanning display to identify a mutant inhibitor, WAp-D04-W10P, with 5-fold greater potency in a reporter assay. This work represents the first instance of molecules capable of inhibiting Wnt signaling through direct interaction with a Wnt protein, a molecular class for which targeting has been challenging due its highly hydrophobic nature.

Adjuvant drug-assisted bone healing: Part II - Modulation of angiogenesis

 The treatment of critical-size bone defects following complicated fractures, infections or tumor resections is a major challenge. The same applies to fractures in patients with impaired bone healing due to systemic inflammatory and metabolic diseases. Despite considerable progress in development and establishment of new surgical techniques, design of bone graft substitutes and imaging techniques, these scenarios still represent unresolved clinical problems. However, the development of new active substances offers novel potential solutions for these issues. This work discusses therapeutic approaches that influence angiogenesis or hypoxic situations in healing bone and surrounding tissue. In particular, literature on sphingosine-1-phosphate receptor modulators and nitric oxide (NO•) donors, including bi-functional (hybrid) compounds like NO•-releasing cyclooxygenase-2 inhibitors, was critically reviewed with regard to their local and systemic mode of action.

Adjuvant drug-assisted bone healing: Part III - Further strategies for local and systemic modulation

In this third in a series of reviews on adjuvant drug-assisted bone healing, further approaches aiming at influencing the healing process are discussed. Local and systemic modulation of bone metabolism is pursued with use of a number of drugs with completely different indications, which are characterized by a pleiotropic spectrum of action. These include drugs used to treat lipid disorders (HMG-CoA reductase inhibitors), hypertension (ACE inhibitors), osteoporosis (bisphosphonates), cancer (proteasome inhibitors) and others. Potential applications to enhance bone healing are discussed.

An MXD1-derived repressor peptide identifies noncoding mediators of MYC-driven cell proliferation

MYC controls the transcription of large numbers of long noncoding RNAs (lncRNAs). Since MYC is a ubiquitous oncoprotein, some of these lncRNAs probably play a significant role in cancer. We applied CRISPR interference (CRISPRi) to the identification of MYC-regulated lncRNAs that are required for MYC-driven cell proliferation in the P493-6 and RAMOS human lymphoid cell lines. We identified 320 noncoding loci that play positive roles in cell growth. Transcriptional repression of any one of these lncRNAs reduces the proliferative capacity of the cells. Selected hits were validated by RT-qPCR and in CRISPRi competition assays with individual GFP-expressing sgRNA constructs. We also showed binding of MYC to the promoter of two candidate genes by chromatin immunoprecipitation. In the course of our studies, we discovered that the repressor domain SID (SIN3-interacting domain) derived from the MXD1 protein is highly effective in P493-6 and RAMOS cells in terms of the number of guides depleted in library screening and the extent of the induced transcriptional repression. In the cell lines used, SID is superior to the KRAB repressor domain, which serves routinely as a transcriptional repressor domain in CRISPRi. The SID transcriptional repressor domain is effective as a fusion to the MS2 aptamer binding protein MCP, allowing the construction of a doxycycline-regulatable CRISPRi system that allows controlled repression of targeted genes and will facilitate the functional analysis of growth-promoting lncRNAs.

Harnessing Fiber Diameter-Dependent Effects of Myoblasts Toward Biomimetic Scaffold-Based Skeletal Muscle Regeneration

Regeneration of skeletal muscles is limited in cases of volumetric muscle loss and muscle degenerative diseases. Therefore, there is a critical need for developing strategies that provide cellular and structural support for skeletal muscle regeneration. In the present work, a bioengineered cell niche composed of mechanically competent aligned polyester fiber scaffolds is developed to mimic the oriented muscle fiber microenvironment by electrospinning poly(lactide-co-glycolide) (PLGA) using a custom-designed rotating collector with interspaced parallel blades. Aligned fiber scaffolds with fiber diameters ranging from 335 ± 154 nm to 3013 ± 531 nm are characterized for their bioactivities in supporting growth and differentiation of myoblasts. During in vitro culture, polymeric scaffolds with larger fiber diameter support enhanced alignment, growth, and differentiation of myoblasts associated with phosphorylation of p38 MAPK and upregulated expression of myogenin and myosin heavy chain. In vivo studies using a dystrophin-deficient mdx mouse model show that optimized fiber scaffolds seeded with primary myoblasts result in formation of dystrophin-positive myofibers network in tibialis anterior muscles. Collectively, these experiments provide critical insights on harnessing interactions between muscle cells and engineered fiber matrices to develop effective biomaterials for accelerated muscle regeneration.

CYP2J2 Modulates Diverse Transcriptional Programs in Adult Human Cardiomyocytes

CYP2J2, a member of the Cytochrome P450 family of enzymes, is the most abundant epoxygenase in the heart and has multifunctional properties including bioactivation of arachidonic acid to epoxyeicosatrienoic acids, which, in turn, have been implicated in mediating several cardiovascular conditions. Using a proteomic approach, we found that CYP2J2 expression is lower in cardiac tissue from patients with cardiomyopathy compared to controls. In order to better elucidate the complex role played by CYP2J2 in cardiac cells, we performed targeted silencing of CYP2J2 expression in human adult ventricular cardiomyocytes and interrogated whole genome transcriptional responses. We found that knockdown of CYP2J2 elicits widespread alterations in gene expression of ventricular cardiomyocytes and leads to the activation of a diverse repertoire of programs, including those involved in ion channel signaling, development, extracellular matrix, and metabolism. Several members of the differentially up-regulated ion channel module have well-known pathogenetic roles in cardiac dysrhythmias. By leveraging causal network and upstream regulator analysis, we identified several candidate drivers of the observed transcriptional response to CYP2J2 silencing; these master regulators have been implicated in aberrant cardiac remodeling, heart failure, and myocyte injury and repair. Collectively, our study demonstrates that CYP2J2 plays a central and multifaceted role in cardiomyocyte homeostasis and provides a framework for identifying critical regulators and pathways influenced by this gene in cardiovascular health and disease.

Integrated bioinformatics analysis of aberrantly-methylated differentially-expressed genes and pathways in age-related macular degeneration

Background

Age-related macular degeneration (AMD) represents the leading cause of visual impairment in the aging population. The goal of this study was to identify aberrantly-methylated, differentially-expressed genes (MDEGs) in AMD and explore the involved pathways via integrated bioinformatics analysis.

Methods

Data from expression profile GSE29801 and methylation profile GSE102952 were obtained from the Gene Expression Omnibus database. We analyzed differentially-methylated genes and differentially-expressed genes using R software. Functional enrichment and protein–protein interaction (PPI) network analysis were performed using the R package and Search Tool for the Retrieval of Interacting Genes online database. Hub genes were identified using Cytoscape.

Results

In total, 827 and 592 genes showed high and low expression, respectively, in GSE29801; 4117 hyper-methylated genes and 511 hypo-methylated genes were detected in GSE102952. Based on overlap, we categorized 153 genes as hyper-methylated, low-expression genes (Hyper-LGs) and 24 genes as hypo-methylated, high-expression genes (Hypo-HGs). Four Hyper-LGs (CKB, PPP3CA, TGFB2, SOCS2) overlapped with AMD risk genes in the Public Health Genomics and Precision Health Knowledge Base. KEGG pathway enrichment analysis indicated that Hypo-HGs were enriched in the calcium signaling pathway, whereas Hyper-LGs were enriched in sphingolipid metabolism. In GO analysis, Hypo-HGs were enriched in fibroblast migration, membrane raft, and coenzyme binding, among others. Hyper-LGs were enriched in mRNA transport, nuclear speck, and DNA binding, among others. In PPI network analysis, 23 nodes and two edges were established from Hypo-HGs, and 151 nodes and 73 edges were established from Hyper-LGs. Hub genes (DHX9, MAPT, PAX6) showed the greatest overlap.

Conclusion

This study revealed potentially aberrantly MDEGs and pathways in AMD, which might improve the understanding of this disease.

Developmental characterization of Zswim5 expression in the progenitor domains and tangential migration pathways of cortical interneurons in the mouse forebrain

GABAergic interneurons play an essential role in modulating cortical networks. The progenitor domains of cortical interneurons are localized in developing ventral forebrain, including the medial ganglionic eminence (MGE), caudal ganglionic eminence (CGE), preoptic area (POA), and preoptic hypothalamic border domain (POH). Here, we characterized the expression pattern of Zswim5, an MGE-enriched gene in the mouse forebrain. At E11.5-E13.5, prominent Zswim5 expression was detected in the subventricular zone (SVZ) of MGE, POA, and POH, but not CGE of ventral telencephalon where progenitors of cortical interneurons resided. At E15.5 and E17.5, Zswim5 expression remained in the MGE/pallidum primordium and ventral germinal zone. Zswim5 mRNA was markedly decreased after birth and was absent in the adult forebrain. Interestingly, the Zswim5 expression pattern resembled the tangential migration pathways of cortical interneurons. Zswim5-positive cells in the MGE appeared to migrate from the MGE through the SVZ of LGE to overlying neocortex. Indeed, Zswim5 was co-localized with Nkx2.1 and Lhx6, markers of progenitors and migratory cortical interneurons. Double labeling showed that Ascl1/Mash1-positive cells co-expressed Zswim5. Zswim5 expressing cells contained none or at most low levels of Ki67 but co-expressed Tuj1 in the SVZ of MGE. These results suggest that Zswim5 is immediately upregulated as progenitors exiting cell cycle become postmitotic. Given that recent studies have elucidated that the cell fate of cortical interneurons is determined shortly after becoming postmitotic, the timing of Zswim5 expression in early postmitotic interneurons suggests a potential role of Zswim5 in regulation of neurogenesis and tangential migration of cortical interneurons.

Runx1 negatively regulates inflammatory cytokine production by neutrophils in response to Toll-like receptor signaling

RUNX1 is frequently mutated in myeloid and lymphoid malignancies. It has been shown to negatively regulate Toll-like receptor 4 (TLR4) signaling through nuclear factor κB (NF-κB) in lung epithelial cells. Here we show that RUNX1 regulates TLR1/2 and TLR4 signaling and inflammatory cytokine production by neutrophils. Hematopoietic-specific RUNX1 loss increased the production of proinflammatory mediators, including tumor necrosis factor-α (TNF-α), by bone marrow neutrophils in response to TLR1/2 and TLR4 agonists. Hematopoietic RUNX1 loss also resulted in profound damage to the lung parenchyma following inhalation of the TLR4 ligand lipopolysaccharide (LPS). However, neutrophils with neutrophil-specific RUNX1 loss lacked the inflammatory phenotype caused by pan-hematopoietic RUNX1 loss, indicating that dysregulated TLR4 signaling is not due to loss of RUNX1 in neutrophils per se. Rather, single-cell RNA sequencing indicates the dysregulation originates in a neutrophil precursor. Enhanced inflammatory cytokine production by neutrophils following pan-hematopoietic RUNX1 loss correlated with increased degradation of the inhibitor of NF-κB signaling, and RUNX1-deficient neutrophils displayed broad transcriptional upregulation of many of the core components of the TLR4 signaling pathway. Hence, early, pan-hematopoietic RUNX1 loss de-represses an innate immune signaling transcriptional program that is maintained in terminally differentiated neutrophils, resulting in their hyperinflammatory state. We hypothesize that inflammatory cytokine production by neutrophils may contribute to leukemia associated with inherited RUNX1 mutations.

Metformin inhibits high glucose-induced smooth muscle cell proliferation and migration

We investigated the protective effects and mechanism of action of metformin on high glucose-induced smooth muscle cell proliferation and migration. Vascular smooth muscle cells (VSMCs) were subjected to a series of concentrations (0-10 mM) of metformin. CCK-8, wound healing, and transwell assays were performed. Correlations between metformin concentration and high-mobility group box 1 (HMGB1) and miR-142-3p levels were assessed. In addition, miR-142-3p mimic and siRNA were used to investigate VSMC migration in the presence or absence of metformin. In the high-glucose condition, metformin decreased cell growth and inhibited cell migration. HMGB1 gene expression correlated negatively with metformin concentration, whereas miR-142-3p expression correlated positively with metformin concentration. In addition, mimic-induced miR-142-3p elevation resulted in decreased HMGB1 and LC3II levels and elevated p62 levels in the high-glucose condition, whereas miR-142-3p knockdown had the reverse effects, and metformin abolished those effects. Metformin inhibits high glucose–induced VSMC hyperproliferation and increased migration by inducing miR-142-3p-mediated inhibition of HMGB1 expression via the HMGB1-autophagy related pathway.

Molecular Simulation of Mechanical Properties and Membrane Activities of the ESCRT-III Complexes

The endosomal sorting complex required for transport (ESCRT) machinery carries out the membrane scission reactions that are required for many biological processes throughout cells. How ESCRTs bind and deform cellular membranes and ultimately produce vesicles has been a matter of active research in recent years. In this study, we use fully atomistic molecular dynamics simulations to scrutinize the structural details of a filament composed of Vps32 protomers, a major component of ESCRT-III complexes. The simulations show that both hydrophobic and electrostatic interactions between monomers help maintain the structural stability of the filament, which exhibits an intrinsic bend and twist. Our findings suggest that the accumulation of bending and twisting stresses as the filament elongates on the membrane surface likely contributes to the driving force for membrane invagination. The filament exposes a large cationic surface that senses the negatively charged lipids in the membrane, and the N-terminal amphipathic helix of the monomers not only acts as a membrane anchor but also generates significant positive membrane curvature. Taking all results together, we discuss a plausible mechanism for membrane invagination driven by ESCRT-III.

miR-23a-3p/SIX1 regulates glucose uptake and proliferation through GLUT3 in head and neck squamous cell carcinomas

SIX1 overexpression has been reported in several cancers. However, its involvement in head and neck squamous cell carcinoma (HNSCC) remains unclear. In this study we investigated the clinical significance and biological roles of SIX1 in HNSCC. SIX1 expression was upregulated in HNSCC and correlated with TNM stage and nodal metastasis. Analysis of TCGA dataset demonstrated that high SIX1 expression correlated with poor patient prognosis. Overexpression of SIX1 in the Fadu cell line upregulated cell proliferation, colony formation, glucose uptake and ATP production. In contrast, SIX1 depletion in the Detroit562 cell line downregulated cell proliferation, colony formation, glucose uptake and ATP production. We analyzed a series of genes involved in glucose metabolism and found that SIX1 overexpression upregulated GLUT3, an important glucose transporter, at both mRNA and protein levels. Using the TRANSFAC database, we found that SIX1 had potential binding sites on the GLUT3 promoter, which was validated by chromatin immunoprecipitation (ChIP) assays. Next, we focused on miR-23a-3p, which could target SIX1 in HNSCC cells. The miR-23a-3p mimic downregulated SIX1 expression while the miR-23a-3p inhibitor upregulated SIX1 expression. The binding of miR-23a-3p to the 3'-UTR of SIX1 was confirmed using the luciferase reporter assay. Analysis of TCGA dataset showed a negative correlation between the miR-23a-3p and SIX1. Furthermore, the miR-23a-3p mimic inhibited cell proliferation, ATP production and glucose uptake, which could be rescued by transfection with the SIX1 plasmid. In summary, our study demonstrated that SIX1 facilitated HNSCC cell growth through regulation of GLUT3 and glucose uptake. miR-23a-3p targeted the SIX1/GLUT3 axis and suppressed glucose uptake and proliferation in HNSCC.

Site-directed MT1-MMP trafficking and surface insertion regulate AChR clustering and remodeling at developing NMJs

At vertebrate neuromuscular junctions (NMJs), the synaptic basal lamina contains different extracellular matrix (ECM) proteins and synaptogenic factors that induce and maintain synaptic specializations. Here, we report that podosome-like structures (PLSs) induced by ubiquitous ECM proteins regulate the formation and remodeling of acetylcholine receptor (AChR) clusters via focal ECM degradation. Mechanistically, ECM degradation is mediated by PLS-directed trafficking and surface insertion of membrane-type 1 matrix metalloproteinase (MT1-MMP) to AChR clusters through microtubule-capturing mechanisms. Upon synaptic induction, MT1-MMP plays a crucial role in the recruitment of aneural AChR clusters for the assembly of postsynaptic specializations. Lastly, the structural defects of NMJs in embryonic MT1-MMP^-/- mice further demonstrate the physiological role of MT1-MMP in normal NMJ development. Collectively, this study suggests that postsynaptic MT1-MMP serves as a molecular switch to synaptogenesis by modulating local ECM environment for the deposition of synaptogenic signals that regulate postsynaptic differentiation at developing NMJs.

Role of cell polarity and planar cell polarity (PCP) proteins in spermatogenesis

Studies on cell polarity proteins and planar cell polarity (PCP) proteins date back to almost 40 years ago in Drosophila and C. elegans when these proteins were shown to be crucial to support apico-basal polarity and also directional alignment of polarity cells across the plane of an epithelium during morphogenesis. In adult mammals, cell polarity and PCP are most notable in cochlear hair cells. However, the role of these two groups of proteins to support spermatogenesis was not explored until a decade earlier when several proteins that confer cell polarity and PCP proteins were identified in the rat testis. Since then, there are several reports appearing in the literature to examine the role of both cell polarity and PCP in supporting spermatogenesis. Herein, we provide an overview regarding the role of cell polarity and PCP proteins in the testis, evaluating these findings in light of studies in other mammalian epithelial cells/tissues. Our goal is to provide a timely evaluation of these findings, and provide some thought provoking remarks to guide future studies based on an evolving concept in the field.

Combined Transplantation of Olfactory Ensheathing Cells With Rat Neural Stem Cells Enhanced the Therapeutic Effect in the Retina of RCS Rats

Retinal degenerative diseases (RDDs) are the leading causes of blindness and currently lack effective treatment. Cytotherapy has become a promising strategy for RDDs. The transplantation of olfactory ensheathing cells (OECs) or neural stem cells (NSCs) has recently been applied for the experimental treatment of RDDs. However, the long-term outcomes of single-cell transplantation are poor. The combined transplantation of multiple types of cells might achieve better effects. In the present study, OECs [containing olfactory nerve fibroblasts (ONFs)] and NSCs were cotransplanted into the subretinal space of Royal College of Surgeons (RCS) rats. Using electroretinogram (ERG), immunofluorescence, Western blot, and in vitro Transwell system, the differences in the electrophysiological and morphological changes of single and combined transplantation as well as the underlying mechanisms were explored at 4, 8, and 12 weeks postoperation. In addition, using the Transwell system, the influence of OECs on the stemness of NSCs was discovered. Results showed that, compared to the single transplantation of OECs or NSCs, the combined transplantation of OECs and NSCs produced greater improvements in b-wave amplitudes in ERGs and the thickness of the outer nuclear layer at all three time points. More endogenous stem cells were found within the retina after combined transplantation. Glial fibrillary acidic protein (GFAP) expression decreased significantly when NSCs were cotransplanted with OECs. Both the vertical and horizontal migration of grafted cells were enhanced in the combined transplantation group. Meanwhile, the stemness of NSCs was also better maintained after coculture with OECs. Taken together, the results suggested that the combined transplantation of NSCs and OECs enhanced the improvement in retinal protection in RCS rats, providing a new strategy to treat RDDs in the future.

Genetic compensation in a stable slc25a46 mutant zebrafish: A case for using F0 CRISPR mutagenesis to study phenotypes caused by inherited disease

A phenomenon of genetic compensation is commonly observed when an organism with a disease-bearing mutation shows incomplete penetrance of the disease phenotype. Such incomplete phenotypic penetrance, or genetic compensation, is more commonly found in stable knockout models, rather than transient knockdown models. As such, these incidents present a challenge for the disease modeling field, although a deeper understanding of genetic compensation may also hold the key for novel therapeutic interventions. In our study we created a knockout model of slc25a46 gene, which is a recently discovered important player in mitochondrial dynamics, and deleterious mutations in which are known to cause peripheral neuropathy, optic atrophy and cerebellar ataxia. We report a case of genetic compensation in a stable slc25a46 homozygous zebrafish mutant (hereafter referred as “mutant”), in contrast to a penetrant disease phenotype in the first generation (F0) slc25a46 mosaic mutant (hereafter referred as “crispant”), generated with CRISPR/Cas-9 technology. We show that the crispant phenotype is specific and rescuable. By performing mRNA sequencing, we define significant changes in slc25a46 mutant’s gene expression profile, which are largely absent in crispants. We find that among the most significantly altered mRNAs, anxa6 gene stands out as a functionally relevant player in mitochondrial dynamics. We also find that our genetic compensation case does not arise from mechanisms driven by mutant mRNA decay. Our study contributes to the growing evidence of the genetic compensation phenomenon and presents novel insights about Slc25a46 function. Furthermore, our study provides the evidence for the efficiency of F0 CRISPR screens for disease candidate genes, which may be used to advance the field of functional genetics.

PP2A phosphatase is required for dendrite pruning via actin regulation in Drosophila

Large‐scale pruning, the developmentally regulated degeneration of axons or dendrites, is an important specificity mechanism during neuronal circuit formation. The peripheral sensory class IV dendritic arborization (c4da) neurons of Drosophila larvae specifically prune their dendrites at the onset of metamorphosis in an ecdysone‐dependent manner. Dendrite pruning requires local cytoskeleton remodeling, and the actin‐severing enzyme Mical is an important ecdysone target. In a screen for pruning factors, we identified the protein phosphatase 2 A (PP2A). PP2A interacts genetically with the actin‐severing enzymes Mical and cofilin as well as other actin regulators during pruning. Moreover, Drosophila cofilin undergoes a change in localization at the onset of metamorphosis indicative of a change in actin dynamics. This change is abolished both upon loss of Mical and PP2A. We conclude that PP2A regulates actin dynamics during dendrite pruning.

Sirt3 is dispensable for oocyte quality and female fertility in lean and obese mice

Mammalian oocytes rely heavily on mitochondrial oxidative phosphorylation (OXPHOS) for generating ATP. However, mitochondria are also the primary source of damaging reactive oxygen species (ROS). Mitochondrial de-regulation, therefore, underpins poor oocyte quality associated with conditions such as obesity and aging. The mitochondrial sirtuin, Sirt3, is critical for mitochondrial respiration and redox regulation. Interestingly, however, Sirt3 knockout (Sirt3^-/- ) mice do not exhibit systemic compromise under basal conditions, only doing so under stressed conditions such as high-fat diet (HFD)-induced obesity. Mouse oocytes depleted of Sirt3 exhibit increased ROS in vitro, but it is unknown whether Sirt3 is necessary for female fertility in vivo. Here, we test this for the first time by investigating ovarian follicular reserve, oocyte maturation (including detailed spindle assembly and chromosome segregation), and female fertility in Sirt3^-/- females. We find that under basal conditions, young Sirt3^-/- females exhibit no defects in any parameters. Surprisingly, all parameters also remain intact following HFD-induced obesity. Despite markedly increased ROS levels in HFD Sirt3^-/- oocytes, ATP levels nevertheless remain normal. Our data support that ATP is sustained in vivo through increased mitochondrial mass possibly secondary to compensatory upregulation of another sirtuin, Sirt1, which has overlapping functions with Sirt3.

Expression profiling of the Kdm genes in scallop Patinopecten yessoensis suggests involvement of histone demethylation in regulation of early development and gametogenesis

Histone demethylation modification is an important means of gene expression regulation and is widely involved in biological processes such as animal reproduction and development. Histone lysine demethylases (Kdm) plays an important role in the demethylation of histones. To understand the role of histone demethylation in scallops, we identified the Kdm gene family of the Yesso scallop Patinopecten yessoensis, and analyzed its expression during the gonad and early development. The results showed that the P. yessoensis has a complete Kdm family including seventeen members that belong to sixteen subfamilies (Hif1an, Hspbap1, Jarid2, Jmjd4, Jmjd6, Jmjd7, Jmjd8, Kdm1, Kdm2, Kdm3, Kdm4, Kdm5, Kdm6, Kdm7, Kdm8 and Kdm9). The Kdm genes showed five different expression patterns in the early development of scallop, with some of them (e.g. Jmjd7, Jmjd8 and Kdm8) being highly expressed in only one or two stage and the others (e.g. Kdm1A, Kdm9, Jmjd4 and Jmjd6) in several consecutive stages. During gonadal development, the Kdm genes also display various expression patterns. Some genes (e.g. Kdm2, Kdm4 and Jmjd7) display preferential expression in the testis, and the others have no obvious sex bias but show stage preference (resting, proliferative, growing or maturation stage). These results suggest that various histone demethylation modifications (e.g. H3K4, H3K9 and H3K27) may participate in the regulation of gametogenesis and early development of Yesso scallop. It will facilitate a better understanding of the epigenetic contributions to mollusk development.

The Switch from NF-YAl to NF-YAs Isoform Impairs Myotubes Formation

NF-YA, the regulatory subunit of the trimeric transcription factor (TF) NF-Y, is regulated by alternative splicing (AS) generating two major isoforms, “long” (NF-YAl) and “short” (NF-YAs). Muscle cells express NF-YAl. We ablated exon 3 in mouse C2C12 cells by a four-guide CRISPR/Cas9n strategy, obtaining clones expressing exclusively NF-YAs (C2-YAl-KO). C2-YAl-KO cells grow normally, but are unable to differentiate. Myogenin and—to a lesser extent, MyoD— levels are substantially lower in C2-YAl-KO, before and after differentiation. Expression of the fusogenic Myomaker and Myomixer genes, crucial for the early phases of the process, is not induced. Myomaker and Myomixer promoters are bound by MyoD and Myogenin, and Myogenin overexpression induces their expression in C2-YAl-KO. NF-Y inactivation reduces MyoD and Myogenin, but not directly: the Myogenin promoter is CCAAT-less, and the canonical CCAAT of the MyoD promoter is not bound by NF-Y in vivo. We propose that NF-YAl, but not NF-YAs, maintains muscle commitment by indirectly regulating Myogenin and MyoD expression in C2C12 cells. These experiments are the first genetic evidence that the two NF-YA isoforms have functionally distinct roles.

Spatial and temporal deletion reveals a latent effect of Megf8 on the left-right patterning and heart development

Laterality disease is frequently associated with congenital heart disease (CHD). However, it is unclear what is behind this association, a pleiotropic effect of common genetic causes of laterality diseases or the impact of abnormal left-right patterning on the downstream cardiovascular development. MEGF8 is a disease gene of Carpenter syndrome characterized by defective lateralization and CHD. Here we performed spatial and temporal deletion to dissect the tissue and time requirements of Megf8 on cardiovascular development. None of conditional deletions in cardiomyocytes, endothelium/endocardium, epicardium, cardiac mesoderm or neural crest cells led to cardiovascular defects. More surprisingly, temporal deletion with a ubiquitous Cre driver at embryonic day 7.5 (E7.5), a time point before symmetry break and cardiogenesis, causes preaxial polydactyly (PPD) and exencephaly, but not laterality and cardiovascular defects. These data suggested that Megf8 was dispensable for cardiac organogenesis. Only with E6.5 deletion, we observed aortic arch artery defects including right aortic arch, an indicator of reversed left-right patterning. The concurrence of laterality and cardiovascular defects in pre-streak stage deletion rather than cardiac organogenesis stage deletion indicates that the laterality defect may directly impact heart development. Interestingly, the latent effect of Megf8 on the left-right patterning suggests that the regulation of laterality may be much earlier than we previously thought.

Sperm SPACA6 protein is required for mammalian Sperm-Egg Adhesion/Fusion

Three genes are known to be essential for gamete adhesion/fusion (Cd9, Izumo1 and Juno). Here, we confirmed that Spaca6 null males are infertile and showed that their sperm accumulate in the perivitelline space but are unable to fuse with oocyte. Like IZUMO1, SPACA6 which is expressed by human sperm, is remained on the equatorial segment after acrosomal reaction and is involved in human fertilization since an anti-SPACA6 antibody inhibited it. Despite the similarity of the phenotypes caused by Spaca6 and Izumo1 knockouts, these are not redundant and the essential relocation of IZUMO1 is not affected by the lack of SPACA6. We propose a model in which IZUMO1 and SPACA6 would be part of a molecular complex necessary for gamete fusion and that their concomitant presence would be required for the recruitment of another essential molecular actor, such as a fusogen, for the fusion to take place.

CD300f immunoreceptor is associated with major depressive disorder and decreased microglial metabolic fitness

A role for microglia in neuropsychiatric diseases, including major depressive disorder (MDD), has been postulated. Regulation of microglial phenotype by immune receptors has become a central topic in many neurological conditions. We explored preclinical and clinical evidence for the role of the CD300f immune receptor in the fine regulation of microglial phenotype and its contribution to MDD. We found that a prevalent nonsynonymous single-nucleotide polymorphism (C/T, rs2034310) of the human CD300f receptor cytoplasmic tail inhibits the protein kinase C phosphorylation of a threonine and is associated with protection against MDD, mainly in women. Interestingly, CD300f-/- mice displayed several characteristic MDD traits such as augmented microglial numbers, increased interleukin 6 and interleukin 1 receptor antagonist messenger RNA, alterations in synaptic strength, and noradrenaline-dependent and persistent depressive-like and anhedonic behaviors in females. This behavioral phenotype could be potentiated inducing the lipopolysaccharide depression model. RNA sequencing and biochemical studies revealed an association with impaired microglial metabolic fitness. In conclusion, we report a clear association that links the function of the CD300f immune receptor with MDD in humans, depressive-like and anhedonic behaviors in female mice, and altered microglial metabolic reprogramming.

KCTD12 promotes G1/S transition of breast cancer cell through activating the AKT/FOXO1 signaling

Background

Sustaining proliferation is the most fundamental step for breast cancer tumor genesis. Accelerated proliferation is usually linked to the uncontrolled cell cycle. However, the internal and external factors linked to the activation of breast cancer cell cycle are still to be investigated.

Methods

quantitative PCR (qPCR) and Western blotting assay were used to detect the expression of potassium channel tetramerization domain containing 12 (KCTD12) in breast cancer. MTT and colony formation assays were performed to evaluate the effect of KCTD12 on cell proliferation of breast cancer. Anchorage‐independent growth assay was used to examine the in vitro tumorigenesis of breast cancer cells. Flow cytometry assay, qPCR, and Western blotting were used to investigate the detailed mechanisms of KCTD12 on breast cancer progression.

Results

Herein, the result showed that the level of KCTD12 is significantly decreased in breast cancer tissues and cells, and lower level of KCTD12 predicts poorer survival for patients with breast cancer. Further cell function tests illustrated that downregulation of KCTD12 significantly promotes cell proliferation and in vitro tumor genesis. Besides, molecular biologic experiments showed that downregulation of KCTD12 can enhance the G1/S transition through activating the AKT/FOXO1 signaling.

Conclusion

Our study inferred that downregulation of KCTD12 can be a novel factor for poor prognosis in breast cancer.

Intracellular Communication among Morphogen Signaling Pathways during Vertebrate Body Plan Formation

During embryonic development in vertebrates, morphogens play an important role in cell fate determination and morphogenesis. Bone morphogenetic proteins (BMPs) belonging to the transforming growth factor-β (TGF-β) family control the dorsal-ventral (DV) patterning of embryos, whereas other morphogens such as fibroblast growth factor (FGF), Wnt family members, and retinoic acid (RA) regulate the formation of the anterior-posterior (AP) axis. Activation of morphogen signaling results in changes in the expression of target genes including transcription factors that direct cell fate along the body axes. To ensure the correct establishment of the body plan, the processes of DV and AP axis formation must be linked and coordinately regulated by a fine-tuning of morphogen signaling. In this review, we focus on the interplay of various intracellular regulatory mechanisms and discuss how communication among morphogen signaling pathways modulates body axis formation in vertebrate embryos.

ECE2 regulates neurogenesis and neuronal migration during human cortical development

During embryonic development, excitatory projection neurons migrate in the cerebral cortex giving rise to organised layers. Periventricular heterotopia (PH) is a group of aetiologically heterogeneous disorders in which a subpopulation of newborn projection neurons fails to initiate their radial migration to the cortex, ultimately resulting in bands or nodules of grey matter lining the lateral ventricles. Although a number of genes have been implicated in its cause, currently they only satisfactorily explain the pathogenesis of the condition for 50% of patients. Novel gene discovery is complicated by the extreme genetic heterogeneity recently described to underlie its cause. Here, we study the neurodevelopmental role of endothelin‐converting enzyme‐2 (ECE2) for which two biallelic variants have been identified in two separate patients with PH. Our results show that manipulation of ECE2 levels in human cerebral organoids and in the developing mouse cortex leads to ectopic localisation of neural progenitors and neurons. We uncover the role of ECE2 in neurogenesis, and mechanistically, we identify its involvement in the generation and secretion of extracellular matrix proteins in addition to cytoskeleton and adhesion.

AMPK Regulates Developmental Plasticity through an Endogenous Small RNA Pathway in Caenorhabditis elegans

Caenorhabditis elegans larvae can undergo developmental arrest upon entry into the dauer stage in response to suboptimal growth conditions. Dauer larvae can exit this stage in replete conditions with no reproductive consequence. During this diapause stage, the metabolic regulator AMP-activated protein kinase (AMPK) ensures that the germ line becomes quiescent to maintain germ cell integrity. Animals that lack all AMPK signalling undergo germline hyperplasia upon entering dauer, while those that recover from this stage become sterile. Neuronal AMPK expression in otherwise AMPK-deficient animals is sufficient for germline quiescence and germ cell integrity and its effects are likely mediated through an endogenous small RNA pathway. Upon impairing small RNA biosynthesis, the post-dauer fertility is restored in AMPK mutants. These data suggest that AMPK may function in neurons to relay a message through small RNAs to the germ cells to alter their quiescence in the dauer stage, thus challenging the permeability of the Weismann barrier.

Expression of RSK4, CD44 and MMP-9 is upregulated and positively correlated in metastatic ccRCC

BACKGROUND

To investigate the expression and function of RSK4, MMP-9 and CD44 in primary clear cell renal cell carcinoma (primary ccRCC) and metastatic clear cell renal cell carcinoma (metastatic ccRCC), as well as the correlation with clinicopathological features of patients.

METHOD

The expression levels of RSK4, CD44 and MMP-9 in 52 primary ccRCC samples and 48 metastatic ccRCC samples were detected by immunohistochemistry, and the relationship between RSK4, CD44 and MMP-9 expression and clinicopathological features as well as prognosis of metastatic ccRCC patients was statistically analysed. Ectopic RSK4 expression in ccRCC cell lines was performed to determine its effect on cell cycle regulation, tumour invasiveness, and metastatic capability.

RESULTS

The positive rates of RSK4, MMP-9 and CD44 expression in metastatic ccRCC tissues were 75, 68.75 and 91.7%, respectively, while the rates in primary ccRCC tissues were 44.2, 34.6 and 69.2%, respectively. Thus, the positive rates in metastatic ccRCC were higher than those in primary ccRCC (PRSK4 = 0. 002; PMMP-9 = 0. 002; PCD44 = 0. 001). However, the expression of RSK4, CD44 and MMP-9 was unrelated to age, gender, or metastatic sites (P > 0.05) but was related to WHO/ISUP nucleolar grade (PRSK4 = 0.019; PCD44 = 0.026; PMMP-9 = 0.049). In metastatic ccRCC, expression among the three proteins showed a positive correlation (P = 0.008). Moreover, expression between RSK4 and CD44 (P = 0.019) and MMP-9 and CD44 (P = 0.05) also showed positive correlations, whereas RSK4 and MMP-9 showed no significant correlation (P = 1.00). Molecular studies showed that overexpression of RSK4 could enhance the invasive and migratory abilities of ccRCC cell lines through the regulation of CD44 and MMP-9 expression and vice versa.

CONCLUSIONS

The overexpression of RSK4, MMP-9 and CD44 is associated with the invasion and metastasis of ccRCC, indicating that they could be potential prognostic factors and serve as new potential therapeutic targets for ccRCC.

CD29 identifies IFN-γ-producing human CD8+ T cells with an increased cytotoxic potential

Cytotoxic CD8+ T cells can effectively kill target cells by producing cytokines, chemokines, and granzymes. Expression of these effector molecules is however highly divergent, and tools that identify and preselect CD8+ T cells with a cytotoxic expression profile are lacking. Human CD8+ T cells can be divided into IFN-γ- and IL-2-producing cells. Unbiased transcriptomics and proteomics analysis on cytokine-producing fixed CD8+ T cells revealed that IL-2+ cells produce helper cytokines, and that IFN-γ+ cells produce cytotoxic molecules. IFN-γ+ T cells expressed the surface marker CD29 already prior to stimulation. CD29 also marked T cells with cytotoxic gene expression from different tissues in single-cell RNA-sequencing data. Notably, CD29+ T cells maintained the cytotoxic phenotype during cell culture, suggesting a stable phenotype. Preselecting CD29-expressing MART1 TCR-engineered T cells potentiated the killing of target cells. We therefore propose that CD29 expression can help evaluate and select for potent therapeutic T cell products.

Light affects tissue patterning of the hypocotyl in the shade-avoidance response

Plants have evolved strategies to avoid shade and optimize the capture of sunlight. While some species are tolerant to shade, plants such as Arabidopsis thaliana are shade-intolerant and induce elongation of their hypocotyl to outcompete neighboring plants. We report the identification of a developmental module acting downstream of shade perception controlling vascular patterning. We show that Arabidopsis plants react to shade by increasing the number and types of water-conducting tracheary elements in the vascular cylinder to maintain vascular density constant. Mutations in genes affecting vascular patterning impair the production of additional xylem and also show defects in the shade-induced hypocotyl elongation response. Comparative analysis of the shade-induced transcriptomes revealed differences between wild type and vascular patterning mutants and it appears that the latter mutants fail to induce sets of genes encoding biosynthetic and cell wall modifying enzymes. Our results thus set the stage for a deeper understanding of how growth and patterning are coordinated in a dynamic environment.

Shade sensitive plants such as Arabidopsis respond to shade by growing tall in order to maximize their access to sunlight. We find that the REVOLUTA (REV) and KANADI1 (KAN1) transcription factors which are primarily involved in patterning the early leaf, impinge on the regulation of WUSCHEL HOMEOBOX4 (WOX4), another transcription factor involved in vascular development. The regulation of WOX4 leads to an increase of the number of water-conducting xylem cells in response to shade. Consequently, mutations in the genes encoding either REV, KAN1 or WOX4 are impaired in their ability to grow tall in shade. Thus, we have uncovered a connection between basic patterning and adaptive growth.

The transcription factor Spalt and human homologue SALL4 induce cell invasion via the dMyc-JNK pathway in Drosophila

Cancer cell metastasis is a leading cause of mortality in cancer patients. Therefore, revealing the molecular mechanism of cancer cell invasion is of great significance for the treatment of cancer. In human patients, the hyperactivity of transcription factor Spalt-like 4 (SALL4) is sufficient to induce malignant tumorigenesis and metastasis. Here, we found that when ectopically expressing the Drosophila homologue spalt (sal) or human SALL4 in Drosophila, epithelial cells delaminated basally with penetration of the basal lamina and degradation of the extracellular matrix, which are essential properties of cell invasion. Further assay found that sal/SALL4 promoted cell invasion via dMyc-JNK signaling. Inhibition of the c-Jun N-terminal kinase (JNK) signaling pathway through suppressing matrix metalloprotease 1, or basket can achieve suppression of cell invasion. Moreover, expression of dMyc, a suppressor of JNK signaling, dramatically blocked cell invasion induced by sal/SALL4 in the wing disc. These findings reveal a conserved role of sal/SALL4 in invasive cell movement and link the crucial mediator of tumor invasion, the JNK pathway, to SALL4-mediated cancer progression.This article has an associated First Person interview with the first author of the paper.

Identification of primordial germ cell-like cells as liver metastasis initiating cells in mouse tumour models

Liver metastasis, characterized by the spread of tumors to the liver from other areas, represents a deadly disease with poor prognosis. Currently, there is no effective therapeutic strategies and/or agents to combat liver metastasis primarily due to the insufficient understanding of liver metastasis. To develop a promising strategy for targeting liver metastasis, understanding of a cell origin responsible for liver metastasis and how this cell can be pharmacologically eliminated are therefore crucial. Using diverse tumor models including p53 -/- genetic mouse model and syngeneic tumor models, we identified primordial germ cell (PGC)-like tumor cells, which are enriched in earliest liver micro-metastasis (up to 99%), as a cell origin of liver metastasis. PGC-like tumor cells formed earliest micro-metastasis in liver and gradually differentiated into non-PGC-like tumor cells to constitute late macro-metastasis in the course of tumor metastasis. The liver metastasis-initiating cells (PGC-like tumor cells) display cell renewal and differentiation capabilities, resemble primordial germ cells (PGCs) in morphology and PGC marker gene expression, and express higher level of the genes linked to metastasis and immune escape compared with non-PGC-like tumor cells. Of note, Stellarhigh PGC-like tumor cells, but not Stellarlow non-PGC-like cells, sorted from primary tumors of p53 -/- mice readily form liver metastasis. Depletion of PGC-like tumor cells through genetic depletion of any of key germ cell genes impairs liver metastasis, while increased PGC-like tumor cells by SMAD2 knockout is correlated with markedly enhanced liver metastasis. Finally, we present the proof of principle evidence that pharmacologically targeting BMP pathways serves as a promising strategy to eliminate PGC-like tumor cells leading to abrogating liver metastasis. Collectively, our study identifies PGC-like tumor cells as a cell origin of liver metastasis, whose depletion by genetically targeting core PGC developmental genes or pharmacologically inhibiting BMP pathways serves a promising strategy for targeting liver metastasis.

Pathological calcification in osteoarthritis: an outcome or a disease initiator?

In the progression of osteoarthritis, pathological calcification in the affected joint is an important feature. The role of these crystallites in the pathogenesis and progression of osteoarthritis is controversial; it remains unclear whether they act as a disease initiator or are present as a result of joint damage. Recent studies reported that the molecular mechanisms regulating physiological calcification of skeletal tissues are similar to those regulating pathological or ectopic calcification of soft tissues. Pathological calcification takes place when the equilibrium is disrupted. Calcium phosphate crystallites are identified in most affected joints and the presence of these crystallites is closely correlated with the extent of joint destruction. These observations suggest that pathological calcification is most likely to be a disease initiator instead of an outcome of osteoarthritis progression. Inhibiting pathological crystallite deposition within joint tissues therefore represents a potential therapeutic target in the management of osteoarthritis.

SIRT2 Affects Primary Cilia Formation by Regulating mTOR Signaling in Retinal Pigmented Epithelial Cells

SIRT2, a member of the Class III HDAC family, participates in diverse cellular processes and regulates several pathological conditions. Although a few reports show that SIRT2 regulates the cell cycle, the causes and outcomes of SIRT2-dependent cell proliferation remain unclear. Here, we examined the effects of SIRT2 suppression in human RPE1 cells using siRNA targeting SIRT2, and AK-1, a SIRT2-specific inhibitor. The number of primary cilia in SIRT2-suppressed cells increased under serum-present conditions. Suppressing SIRT2 induced cell cycle arrest at G0/G1 phase by inactivating mammalian target of rapamycin (mTOR) signaling, possibly through mTORC1. Treatment with torin 1, an inhibitor of mTORC1/mTORC2, yielded results similar to those observed after SIRT2 suppression. However, SIRT2 suppression did not affect primary cilia formation or mTOR signaling following serum starvation. This suggests that SIRT2 acts as a critical sensor that links growth factor-dependent signal transduction and primary cilia formation by regulating the cell cycle.

Potential role of cyclin-dependent kinase 4/6 inhibitors in the treatment of squamous cell carcinoma of the head and neck

PURPOSE OF REVIEW

Human papillomavirus (HPV)-negative squamous cell carcinoma of the head and neck (SCCHN) is mainly driven by genetic aberrations involved in the cell cycle pathway resulting in cyclin-dependent kinase (CDK) 4 and 6 activation. This supports the investigation of the activity of CDK4/6 inhibitors in this disease. We review the therapeutic potential of CDK4/6 inhibitors in SCCHN.

RECENT FINDINGS

CDK4/6 inhibitors in monotherapy have demonstrated cytostatic activity in HPV-negative SCCHN. Combination with epidermal growth factor inhibitors, with phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathways inhibitors or with immunotherapy, have shown promising preclinical efficacy. No strong predictive biomarkers of response or resistance have been firmly identified.Phase I clinical trials have demonstrated that palbociclib or ribociclib in combination with cetuximab is well tolerated. A phase II single-arm trial combining palbociclib/cetuximab has shown promising results.

SUMMARY

Inhibition of CDK4/6 represents a new potential treatment for HPV-negative SCCHN patients. Randomized clinical trials that investigate these compounds in an unbiased manner are needed to fully evaluate their efficacy. However, it is unlikely that all the patients will benefit from this new approach. To determine a molecular profile/phenotype that will predict CDK4/6 inhibitor activity, researchers will have to take into account simultaneously occurring events in the cyclin-D/CDK4/CDK6/retinoblastoma and associated pathways.

Cellular and Molecular Mechanisms of Kidney Development: From the Embryo to the Kidney Organoid

Development of the metanephric kidney is strongly dependent on complex signaling pathways and cell-cell communication between at least four major progenitor cell populations (ureteric bud, nephron, stromal, and endothelial progenitors) in the nephrogenic zone. In recent years, the improvement of human-PSC-derived kidney organoids has opened new avenues of research on kidney development, physiology, and diseases. Moreover, the kidney organoids provide a three-dimensional (3D) in vitro model for the study of cell-cell and cell-matrix interactions in the developing kidney. In vitro re-creation of a higher-order and vascularized kidney with all of its complexity is a challenging issue; however, some progress has been made in the past decade. This review focuses on major signaling pathways and transcription factors that have been identified which coordinate cell fate determination required for kidney development. We discuss how an extensive knowledge of these complex biological mechanisms translated into the dish, thus allowed the establishment of 3D human-PSC-derived kidney organoids.

The Respiratory Phenotype of Pompe Disease Mouse Models

Pompe disease is a glycogen storage disease caused by a deficiency in acid α-glucosidase (GAA), a hydrolase necessary for the degradation of lysosomal glycogen. This deficiency in GAA results in muscle and neuronal glycogen accumulation, which causes respiratory insufficiency. Pompe disease mouse models provide a means of assessing respiratory pathology and are important for pre-clinical studies of novel therapies that aim to treat respiratory dysfunction and improve quality of life. This review aims to compile and summarize existing manuscripts that characterize the respiratory phenotype of Pompe mouse models. Manuscripts included in this review were selected utilizing specific search terms and exclusion criteria. Analysis of these findings demonstrate that Pompe disease mouse models have respiratory physiological defects as well as pathologies in the diaphragm, tongue, higher-order respiratory control centers, phrenic and hypoglossal motor nuclei, phrenic and hypoglossal nerves, neuromuscular junctions, and airway smooth muscle. Overall, the culmination of these pathologies contributes to severe respiratory dysfunction, underscoring the importance of characterizing the respiratory phenotype while developing effective therapies for patients.

Preterm infants with isolated cerebellar hemorrhage show bilateral cortical alterations at term equivalent age

The cerebellum is connected to numerous regions of the contralateral side of the cerebrum. Motor and cognitive deficits following neonatal cerebellar hemorrhages (CbH) in extremely preterm neonates may be related to remote cortical alterations, following disrupted cerebello-cerebral connectivity as was previously shown within six CbH infants. In this retrospective case series study, we used MRI and advanced surface-based analyses to reconstruct gray matter (GM) changes in cortical thickness and cortical surface area in extremely preterm neonates (median age = 26; range: 24.9-26.7 gestational weeks) with large isolated unilateral CbH (N = 5 patients). Each CbH infant was matched with their own preterm infant cohort (range: 20-36 infants) based on sex and gestational age at birth. On a macro level, our data revealed that the contralateral cerebral hemisphere of CbH neonates did not show less cortical thickness or cortical surface area than their ipsilateral cerebral hemisphere at term. None of the cases differed from their matched cohort groups in average cortical thickness or average cortical surface area in the ipsilateral or contralateral cerebral hemisphere. On a micro (i.e. vertex) level, we established high variability in significant local cortical GM alteration patterns across case-cohort groups, in which the cases showed thicker or bigger volume in some regions, among which the caudal middle frontal gyrus, insula and parahippocampal gyrus, and thinner or less volume in other regions, among which the cuneus, precuneus and supratentorial gyrus. This study highlights that cerebellar injury during postnatal stages may have  widespread bilateral influence on the early maturation of cerebral cortical regions, which implicate complex cerebello-cerebral interactions to be present at term birth.

The FOXO's Advantages of Being a Family: Considerations on Function and Evolution

The nematode Caenorhabditis elegans possesses a unique (with various isoforms) FOXO transcription factor DAF-16, which is notorious for its role in aging and its regulation by the insulin-PI3K-AKT pathway. In humans, five genes (including a protein-coding pseudogene) encode for FOXO transcription factors that are targeted by the PI3K-AKT axis, such as in C. elegans. This common regulation and highly conserved DNA-binding domain are the pillars of this family. In this review, I will discuss the possible meaning of possessing a group of very similar proteins and how it can generate additional functionality to more complex organisms. I frame this discussion in relation to the much larger super family of Forkhead proteins to which they belong. FOXO members are very often co-expressed in the same cell type. The overlap of function and expression creates a certain redundancy that might be a safeguard against the accidental loss of FOXO function, which could otherwise lead to disease, particularly, cancer. This is one of the points that will be examined in this "family affair" report.

Targeting ADAM10 in Cancer and Autoimmunity

Generating inhibitors for A Disintegrin And Metalloproteinase 10 (ADAM10), a zinc-dependent protease, was heavily invested in by the pharmaceutical industry starting over 20 years ago. There has been much enthusiasm in basic research for these inhibitors, with a multitude of studies generating significant data, yet the clinical trials have not replicated the same results. ADAM10 is ubiquitously expressed and cleaves many important substrates such as Notch, PD-L1, EGFR/HER ligands, ICOS-L, TACI, and the "stress related molecules" MIC-A, MIC-B and ULBPs. This review goes through the most recent pre-clinical data with inhibitors as well as clinical data supporting the use of ADAM10 inhibitor use in cancer and autoimmunity. It additionally addresses how ADAM10 inhibitor therapy can be improved and if inhibitor therapy can be paired with other drug treatments to maximize effectiveness in various disease states. Finally, it examines the ADAM10 substrates that are important to each disease state and if any of these substrates or ADAM10 itself is a potential biomarker for disease.

MRTF-A promotes angiotensin II-induced inflammatory response and aortic dissection in mice

Aortic dissection (AD) is a major cause of acute aortic syndrome with high mortality due to the destruction of aortic walls. Although recent studies indicate the critical role of inflammation in the disease mechanism of AD, it is unclear how inflammatory response is initiated. Here, we demonstrate that myocardin-related transcription factor A (MRTF-A), a signal transducer of humoral and mechanical stress, plays an important role in pathogenesis of AD in a mouse model. A mouse model of AD was created by continuous infusion of angiotensin II (AngII) that induced MRTF-A expression and caused AD in 4 days. Systemic deletion of Mrtfa gene resulted in a marked suppression of AD development. Transcriptome and gene annotation enrichment analyses revealed that AngII infusion for 1 day caused pro-inflammatory and pro-apoptotic responses before AD development, which were suppressed by Mrtfa deletion. AngII infusion for 1 day induced pro-inflammatory response, as demonstrated by expressions of Il6, Tnf, and Ccl2, and apoptosis of aortic wall cells, as detected by TUNEL staining, in an MRTF-A-dependent manner. Pharmacological inhibition of MRTF-A by CCG-203971 during AngII infusion partially suppressed AD phenotype, indicating that acute suppression of MRTF-A is effective in preventing the aortic wall destruction. These results indicate that MRTF-A transduces the stress of AngII challenge to the pro-inflammatory and pro-apoptotic responses, ultimately leading to AD development. Intervening this pathway may represent a potential therapeutic strategy.

Effect of miR-181a-3p on osteogenic differentiation of human bone marrow-derived mesenchymal stem cells by targeting BMP10

Objective: To explore the regulation relationship between miR-181a-3p and BMP10, and their mechanism of osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (MSCs).Methods: After osteogenic induction of MSCs, the ALP activity was detected by ELISA. The expression of miRNA-181a-3p and BMP10 was detected by RT-qPCR, and the protein levels of BMP10 and osteogenic differentiation marker proteins ALK and RUNX2 were detected by Western blot. The TargetScan online website was used to predict the putative target of miR-181a-3p, and dual luciferase reporter assay was performed to validate the targeting relationship between miR-181a-3p and BMP10.Results: In osteogenic differentiation of MSCs, ALP activity, the level of ALK and RUNX2 was evidently increased (p < .05), and the expression of miR-181a-3p was significantly downregulated (p < .05). Moreover, overexpression of miR-181a-3p obviously decreased the expression of BMP10 (p < .05), miR-181a-3p knockdown increased the expression of BMP10 prominently (p < .05). The transfection of miR-181a-3p mimics resulted in significantly downregulation of ALP activity and RUNX2 protein expression in MSCs (p < .05). In addition, overexpression of BMP10 could reverse the inhibitory effect of miR-181a-3p on osteogenic differentiation (p < .05).Conclusions: In conclusion, we found that miR-181a-3p inhibited osteogenic differentiation of MCSs by targeting BMP10.

Downregulation of serum exosomal miR-150-5p is associated with poor prognosis in patients with colorectal cancer

Growing evidence have revealed the serum exosomal miRNAs emerged as biomarkers for various cancer types, including colorectal cancer (CRC). Here, we sought to explore the potential clinical significance of serum exosomal miR-150-5p in CRC. A total of 133 CRC patients and 60 healthy volunteers as control group were recruited in this study. Exosomes were isolated from the serum of all the participants. The total RNA was isolated from the exosomes and the serum exosomal miR-150-5p levels were measured by quantitative reverse transcription-polymerase chain reaction. The findings showed that the serum exosomal miR-150-5p levels were significantly reduced in CRC cases compared with those in the control group. Serum exosomal miR-150-5p levels in post-operative blood samples were greatly upregulated one month after surgical treatment. In addition, decreased serum exosomal miR-150-5p expression was closely correlated with poorly differentiation, positive lymph node metastasis and advanced TNM stage. Moreover, receiver operating characteristic (ROC) curve analysis showed serum exosomal miR-150-5p level had good performance to identify CRC cases from healthy volunteers, and a combination of serum exosomal miR-150-5p and carcinoembryonic antigen (CEA) could improve the diagnostic accuracy with an increased the area under the ROC curve (AUC) value. Furthermore, the survival time of patients with higher serum exosomal miR-150-5p expression was significantly longer than those with lower expression. Serum exosomal miR-150-5p was confirmed as an independent prognostic indicator in CRC. Mechanistically, ZEB1 was identified as a direct downstream target of miR-150-5p. Collectively, serum exosomal miR-150-5p might be a novel noninvasive biomarker for CRC diagnosis and prognosis.

Pro-apoptotic and pro-proliferation functions of the JNK pathway of Drosophila: roles in cell competition, tumorigenesis and regeneration

The Jun N-terminal kinase (JNK) is a member of the mitogen-activated protein kinase family. It appears to be conserved in all animal species where it regulates important physiological functions involved in apoptosis, cell migration, cell proliferation and regeneration. In this review, we focus on the functions of JNK in Drosophila imaginal discs, where it has been reported that it can induce both cell death and cell proliferation. We discuss this apparent paradox in the light of recent findings and propose that the pro-apoptotic and the pro-proliferative functions are intrinsic properties of JNK activity. Whether one function or another is predominant depends on the cellular context.

The Caenorhabditis elegans homolog of the Evi1 proto-oncogene, egl-43, coordinates G1 cell cycle arrest with pro-invasive gene expression during anchor cell invasion

Cell invasion allows cells to migrate across compartment boundaries formed by basement membranes. Aberrant cell invasion is a first step during the formation of metastases by malignant cancer cells. Anchor cell (AC) invasion in C. elegans is an excellent in vivo model to study the regulation of cell invasion during development. Here, we have examined the function of egl-43, the homolog of the human Evi1 proto-oncogene (also called MECOM), in the invading AC. egl-43 plays a dual role in this process, firstly by imposing a G1 cell cycle arrest to prevent AC proliferation, and secondly, by activating pro-invasive gene expression. We have identified the AP-1 transcription factor fos-1 and the Notch homolog lin-12 as critical egl-43 targets. A positive feedback loop between fos-1 and egl-43 induces pro-invasive gene expression in the AC, while repression of lin-12 Notch expression by egl-43 ensures the G1 cell cycle arrest necessary for invasion. Reducing lin-12 levels in egl-43 depleted animals restored the G1 arrest, while hyperactivation of lin-12 signaling in the differentiated AC was sufficient to induce proliferation. Taken together, our data have identified egl-43 Evi1 as an important factor coordinating cell invasion with cell cycle arrest.

Cells invasion is a fundamental biological process that allows cells to cross compartment boundaries and migrate to new locations. Aberrant cell invasion is a first step during the formation of metastases by malignant cancer cells. We have investigated how a specialized cell in the Nematode C. elegans, the so-called anchor cell, can invade into the adjacent epithelium during normal development. Our work has identified an oncogenic transcription factor that controls the expression of specific target genes necessary for cell invasion, and at the same time inhibits the proliferation of the invading anchor cell. These findings shed light on the mechanisms, by which cells decide whether to proliferate or invade.