Integrating bulk and single-cell data to predict the prognosis and identify the immune landscape in HNSCC.

The complex interplay between tumour cells and the tumour microenvironment (TME) underscores the necessity for gaining comprehensive insights into disease progression. This study centres on elucidating the elusive the elusive role of endothelial cells within the TME of head and neck squamous cell carcinoma (HNSCC). Despite their crucial involvement in angiogenesis and vascular function, the mechanistic diversity of endothelial cells among HNSCC patients remains largely uncharted. Leveraging advanced single-cell RNA sequencing (scRNA-Seq) technology and the Scissor algorithm, we aimed to bridge this knowledge gap and illuminate the intricate interplay between endothelial cells and patient prognosis within the context of HNSCC. Here, endothelial cells were categorized into Scissorhigh and Scissorlow subtypes. We identified Scissor+ endothelial cells exhibiting pro-tumorigenic profiles and constructed a prognostic risk model for HNSCC. Additionally, four biomarkers also were identified by analysing the gene expression profiles of patients with HNSCC and a prognostic risk prediction model was constructed based on these genes. Furthermore, the correlations between endothelial cells and prognosis of patients with HNSCC were analysed by integrating bulk and single-cell sequencing data, revealing a close association between SHSS and the overall survival (OS) of HNSCC patients with malignant endothelial cells. Finally, we validated the prognostic model by RT-qPCR and IHC analysis. These findings enhance our comprehension of TME heterogeneity at the single-cell level and provide a prognostic model for HNSCC.

6-benzylaminopurine causes endothelial dysfunctions to human umbilical vein endothelial cells and exacerbates atorvastatin-induced cerebral hemorrhage in zebrafish.

6-benzylaminopurine (6-BA), a multifunctional plant growth regulator, which is frequently used worldwide to improve qualities of various crops, is an important ingredient in production of "toxic bean sprouts." Although there is no direct evidence of adverse effects, its hazardous effects, as well as joint toxicity with other chemicals, have received particular attention and aroused furious debate between proponents and environmental regulators. By use of human umbilical vein endothelial cells (HUVECs), adverse effects of 6-BA to human-derived cells were first demonstrated in this study. A total of 25-50 mg 6-BA/L inhibited proliferation, migration, and formation of tubular-like structures by 50% in vitro. Results of Western blot analyses revealed that exposure to 6-BA differentially modulated the MAPK signal transduction pathway in HUVECs. Specifically, 6-BA decreased phosphorylation of MEK and ERK, but increased phosphorylation of JNK and P38. In addition, 6-BA exacerbated atorvastatin-induced cerebral hemorrhage via increasing hemorrhagic occurrence by 60% and areas by 4 times in zebrafish larvae. In summary, 6-BA elicited toxicity to the endothelial system of HUVECs and zebrafish. This was due, at least in part, to discoordination of MAPK signaling pathway, which should pose potential risks to the cerebral vascular system.

Emerging Roles of RNA-Binding Proteins in Inner Ear Hair Cell Development and Regeneration.

RNA-binding proteins (RBPs) regulate gene expression at the post-transcriptional level. They play major roles in the tissue- and stage-specific expression of protein isoforms as well as in the maintenance of protein homeostasis. The inner ear is a bi-functional organ, with the cochlea and the vestibular system required for hearing and for maintaining balance, respectively. It is relatively well documented that transcription factors and signaling pathways are critically involved in the formation of inner ear structures and in the development of hair cells. Accumulating evidence highlights emerging functions of RBPs in the post-transcriptional regulation of inner ear development and hair cell function. Importantly, mutations of splicing factors of the RBP family and defective alternative splicing, which result in inappropriate expression of protein isoforms, lead to deafness in both animal models and humans. Because RBPs are critical regulators of cell proliferation and differentiation, they present the potential to promote hair cell regeneration following noise- or ototoxin-induced damage through mitotic and non-mitotic mechanisms. Therefore, deciphering RBP-regulated events during inner ear development and hair cell regeneration can help define therapeutic strategies for treatment of hearing loss. In this review, we outline our evolving understanding of the implications of RBPs in hair cell formation and hearing disease with the aim of promoting future research in this field.

Mutational analysis of dishevelled genes in zebrafish reveals distinct functions in embryonic patterning and gastrulation cell movements.

Wnt signaling plays critical roles in dorsoventral fate specification and anteroposterior patterning, as well as in morphogenetic cell movements. Dishevelled proteins, or Dvls, mediate the activation of Wnt/ß-catenin and Wnt/planar cell polarity pathways. There are at least three highly conserved Dvl proteins in vertebrates, but the implication of each Dvl in key early developmental processes remains poorly understood. In this study, we use genome-editing approach to generate different combinations of maternal and zygotic dvl mutants in zebrafish, and examine their functions during early development. Maternal transcripts for dvl2 and dvl3a are most abundantly expressed, whereas the transcript levels of other dvl genes are negligible. Phenotypic and molecular analyses show that early dorsal fate specification is not affected in maternal and zygotic dvl2 and dvl3a double mutants, suggesting that the two proteins may be dispensable for the activation of maternal Wnt/ß-catenin signaling. Interestingly, convergence and extension movements and anteroposterior patterning require both maternal and the zygotic functions of Dvl2 and Dvl3a, but these processes are more sensitive to Dvl2 dosage. Zygotic dvl2 and dvl3a double mutants display mild axis extension defect with correct anteroposterior patterning. However, maternal and zygotic double mutants exhibit most strongly impaired convergence and extension movements, severe trunk and posterior deficiencies, and frequent occurrence of cyclopia and craniofacial defects. Our results suggest that Dvl2 and Dvl3a products are required for the activation of zygotic Wnt/ß-catenin signaling and Wnt/planar cell polarity pathway, and regulate zygotic developmental processes in a dosage-dependent manner. This work provides insight into the mechanisms of Dvl-mediated Wnt signaling pathways during early vertebrate development.

Preparation and Luminescence Properties of A-Type Lutecium Silicate Core-Shell Nanospheres.

X-ray radio-luminescence materials have potential application in radiotherapy (RT) and biomedical imaging. Considering that lutecium ions (Lu3+) with high atomic number (Z) have high X-ray attenuation coefficients, Ce3+-doped A-type Lu2SiO5@SiO2 (A-LSO:Ce3+@SiO2) core-shell nanospheres with size in the range of 200-250 nm were prepared through coprecipitation method. The growth mechanism of A-LSO:Ce3+@SiO2 core-shell nanospheres was investigated through determining the phase transition and morphology evolution by XRD, FT-IR, and TEM. The emission spectra, decay profile, and X-ray excited luminescence spectra (XEL) of the obtained samples were collected. The results show that a new type of lutecium silicate core-shell nanospheres A-LSO:Ce3+@SiO2 can be fabricated and exhibit efficient radio-luminescence under X-ray radiation, which has potential application in the diagnosis and therapy of cancer.

Collagen triple helix repeat containing 1a (Cthrc1a) regulates cell adhesion and migration during gastrulation in zebrafish.

Cell adhesion and migration are key cell behaviours during gastrulation in early embryos and metastasis in cancers. Cthrc1 is a secreted protein highly conserved among vertebrates; it is upregulated in injured and diseased arteries, as well as in malignant cancers. There is increasing evidence showing that its expression and activity are associated with cancer progression and inflammatory diseases. However, the mechanism by which it regulates cell migration, and its implication during early development remains unclear. Here we show that zebrafish Cthrc1a is expressed in hypoblast cells, and is required for cell adhesion and migration during gastrulation. Knockdown of cthrc1a in whole embryo inhibits epiboly and convergent extension movements, and reduces the elongation of anteroposterior axis. Cell adhesion assay indicates that Cthrc1a is necessary for mesendoderm cells to interact with fibronectin-coated substratum, and to extend polarised cellular protrusions. Moreover, secreted Cthrc1a proteins diffuse efficiently between blastoderm cells and are recruited by neighbouring cells in an integrin-dependent manner. Consistently, there exists a functional interaction between Cthrc1a and integrin ß1 in anteroposterior axis elongation. These results provide insight into the function of Cthrc1a in the regulation of cell adhesion and migration during embryonic axis elongation.

Autoinhibition of Dishevelled protein regulated by its extreme C terminus plays a distinct role in Wnt/ß-catenin and Wnt/planar cell polarity (PCP) signaling pathways.

Dishevelled (Dvl) is a key intracellular signaling molecule that mediates the activation of divergent Wnt pathways. It contains three highly conserved domains known as DIX, PDZ, and DEP, the functions of which have been well characterized in ß-catenin-dependent canonical and ß-catenin-independent noncanonical Wnt signaling. The C-terminal region is also highly conserved from invertebrates to vertebrates. However, its function in regulating the activation of different Wnt signals remains unclear. We reported previously that Dvl conformational change triggered by the highly conserved PDZ-binding C terminus is important for the pathway specificity. Here we provide further evidence demonstrating that binding of the C terminus to the PDZ domain results in Dvl autoinhibition in the Wnt signaling pathways. Therefore, the forced binding of the C terminus to the PDZ domain reduces the activity of Dvl in noncanonical Wnt signaling, whereas obstruction of this interaction releases Dvl autoinhibition, impairs its functional interaction with LRP6 in canonical Wnt signaling, and increases its specificity in noncanonical Wnt signaling, which is closely correlated with an enhanced Dvl membrane localization. Our findings highlight the importance of the C terminus in keeping Dvl in an appropriate autoinhibited state, accessible for regulation by other partners to switch pathway specificity. Particularly, the C-terminally tagged Dvl fusion proteins that have been widely used to study the function and cellular localization of Dvl may not truly represent the wild-type Dvl because those proteins cannot be autoinhibited.

Comparison of nanofluoridated hydroxyapatite of varying fluoride content for dentin tubule occlusion.

PURPOSE: To evaluate the viability of a series of nano-fluoridated hydroxyapatite (nano-FHA) formulations of varying fluoride content for the occlusion of exposed dentin tubules, in comparison to nano-hydroxyapatite (nano-HA). METHODS: Nano-FHA powders with varying levels of fluoride ion were synthesized to substitute hydroxyl ions (⁻OH) present in hydroxyapatite (HA). Nano-FHA were defined as 2nFHA,4nFHA,6nFHA, 8nFHA and 10nFHA, with the molar ratio of F(⁻ to Ca243; of 0.002,0.004,0.006,0.008 and 0.01, respectively. The powders were synthesized using a wet chemistry route, and characterized by transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The methylthiazol tetrazolium (MTT) assay was used to assess cell viability toward nano-FHA. According to the content of F⁻, the nano-nFHA and nano-HA powders were divided into six groups, with the artificial saliva as control. They were spread over the dentin surface for 1 minute and repeated three times per day for 7 consecutive days. After washing and brushing with distilled water for an additional 7 days, scanning electron microscopy was used to evaluate the in vitro plugging rate of the tubules and penetrating depth. RESULTS: The 2nFHA, 4nFHA, 6nFHA, 8nFHA and 10nFHA powders were prepared and characterized. The 8nFHA had less crystallinity compared to 2nFHA,4nFHA, and 6nFHA.The MTT assay (from 12 to 120 hours) showed that the cell viability of the L-929 fibroblasts in the 2nFHA, 4nFHA, 6nFHA, 8nFHA, 10nFHA, and nano-HA groups ranged from 80.54± 3.35% to 112.9± 4.8%. Most of the nano-FHA powders successfully occluded dentin tubules. The plugging rate of 8nFHA was significantly higher than that of the 2nFHA, 4nFHA, 6nFHA and nano-HA groups. The penetrating depth of the 8nFHA group into the tubules was also significantly higher than that of the other nano-FHA and nano-HA group. CLINICAL SIGNIFICANCE: The nano-FHA formulation 8nFHA showed higher plugging rate and penetrating depth into the tubules. It has the potential to be used as a desensitizing agent in treating dentin hypersensitivity with better long-term durability and efficacy of dentin tubule occlusion.

Flexible, Luminescent Metal-Organic Frameworks Showing Synergistic Solid-Solution Effects on Porosity and Sensitivity.

Mixing molecular building blocks in the solid solution manner is a valuable strategy to obtain structures and properties in between the isostructural parent metal-organic frameworks (MOFs). We report nonlinear/synergistic solid-solution effects using highly related yet non-isostructural, phosphorescent CuI triazolate frameworks as parent phases. Near the phase boundaries associated with conformational diversity and ligand heterogeneity, the porosity (+150 %) and optical O2 sensitivity (410 times, limit of detection 0.07 ppm) can be drastically improved from the best-performing parent MOFs and even exceeds the records hold by precious-metal complexes (3 ppm) and C70 (0.2 ppm).

Hybrid drug-screening strategy identifies potential SARS-CoV-2 cell-entry inhibitors targeting human transmembrane serine protease.

The spread of coronavirus infectious disease (COVID-19) is associated with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which has risked public health more than any other infectious disease. Researchers around the globe use multiple approaches to identify an effective approved drug (drug repurposing) that treats viral infections. Most of the drug repurposing approaches target spike protein or main protease. Here we use transmembrane serine protease 2 (TMPRSS2) as a target that can prevent the virus entry into the cell by interacting with the surface receptors. By hypothesizing that the TMPRSS2 binders may help prevent the virus entry into the cell, we performed a systematic drug screening over the current approved drug database. Furthermore, we screened the Enamine REAL fragments dataset against the TMPRSS2 and presented nine potential drug-like compounds that give us clues about which kinds of groups the pocket prefers to bind, aiding future structure-based drug design for COVID-19. Also, we employ molecular dynamics simulations, binding free energy calculations, and well-tempered metadynamics to validate the obtained candidate drug and fragment list. Our results suggested three potential FDA-approved drugs against human TMPRSS2 as a target. These findings may pave the way for more drugs to be exposed to TMPRSS2, and testing the efficacy of these drugs with biochemical experiments will help improve COVID-19 treatment. Supplementary information: The online version contains supplementary material available at 10.1007/s11224-022-01960-w.