DKK1-SE recruits AP1 to activate the target gene DKK1 thereby promoting pancreatic cancer progression.

Super-enhancers are a class of DNA cis-regulatory elements that can regulate cell identity, cell fate, stem cell pluripotency, and even tumorigenesis. Increasing evidence shows that epigenetic modifications play an important role in the pathogenesis of various types of cancer. However, the current research is far from enough to reveal the complex mechanism behind it. This study found a super-enhancer enriched with abnormally active histone modifications in pancreatic ductal adenocarcinoma (PDAC), called DKK1-super-enhancer (DKK1-SE). The major active component of DKK1-SE is component enhancer e1. Mechanistically, AP1 induces chromatin remodeling in component enhancer e1 and activates the transcriptional activity of DKK1. Moreover, DKK1 was closely related to the malignant clinical features of PDAC. Deletion or knockdown of DKK1-SE significantly inhibited the proliferation, colony formation, motility, migration, and invasion of PDAC cells in vitro, and these phenomena were partly mitigated upon rescuing DKK1 expression. In vivo, DKK1-SE deficiency not only inhibited tumor proliferation but also reduced the complexity of the tumor microenvironment. This study identifies that DKK1-SE drives DKK1 expression by recruiting AP1 transcription factors, exerting oncogenic effects in PDAC, and enhancing the complexity of the tumor microenvironment.

Bone controls browning of white adipose tissue and protects from diet-induced obesity through Schnurri-3-regulated SLIT2 secretion.

The skeleton has been suggested to function as an endocrine organ controlling whole organism energy balance, however the mediators of this effect and their molecular links remain unclear. Here, utilizing Schnurri-3-/- (Shn3-/-) mice with augmented osteoblast activity, we show Shn3-/-mice display resistance against diet-induced obesity and enhanced white adipose tissue (WAT) browning. Conditional deletion of Shn3 in osteoblasts but not adipocytes recapitulates lean phenotype of Shn3-/-mice, indicating this phenotype is driven by skeleton. We further demonstrate osteoblasts lacking Shn3 can secrete cytokines to promote WAT browning. Among them, we identify a C-terminal fragment of SLIT2 (SLIT2-C), primarily secreted by osteoblasts, as a Shn3-regulated osteokine that mediates WAT browning. Lastly, AAV-mediated Shn3 silencing phenocopies the lean phenotype and augmented glucose metabolism. Altogether, our findings establish a novel bone-fat signaling axis via SHN3 regulated SLIT2-C production in osteoblasts, offering a potential therapeutic target to address both osteoporosis and metabolic syndrome.

Stanniocalcin 2 governs cancer cell adaptation to nutrient insufficiency through alleviation of oxidative stress.

Solid tumours often endure nutrient insufficiency during progression. How tumour cells adapt to temporal and spatial nutrient insufficiency remains unclear. We previously identified STC2 as one of the most upregulated genes in cells exposed to nutrient insufficiency by transcriptome screening, indicating the potential of STC2 in cellular adaptation to nutrient insufficiency. However, the molecular mechanisms underlying STC2 induction by nutrient insufficiency and subsequent adaptation remain elusive. Here, we report that STC2 protein is dramatically increased and secreted into the culture media by Gln-/Glc- deprivation. STC2 promoter contains cis-elements that are activated by ATF4 and p65/RelA, two transcription factors activated by a variety of cellular stress. Biologically, STC2 induction and secretion promote cell survival but attenuate cell proliferation during nutrient insufficiency, thus switching the priority of cancer cells from proliferation to survival. Loss of STC2 impairs tumour growth by inducing both apoptosis and necrosis in mouse xenografts. Mechanistically, under nutrient insufficient conditions, cells have increased levels of reactive oxygen species (ROS), and lack of STC2 further elevates ROS levels that lead to increased apoptosis. RNA-Seq analyses reveal STC2 induction suppresses the expression of monoamine oxidase B (MAOB), a mitochondrial membrane enzyme that produces ROS. Moreover, a negative correlation between STC2 and MAOB levels is also identified in human tumour samples. Importantly, the administration of recombinant STC2 to the culture media effectively suppresses MAOB expression as well as apoptosis, suggesting STC2 functions in an autocrine/paracrine manner. Taken together, our findings indicate that nutrient insufficiency induces STC2 expression, which in turn governs the adaptation of cancer cells to nutrient insufficiency through the maintenance of redox homoeostasis, highlighting the potential of STC2 as a therapeutic target for cancer treatment.

Development and experimental validation of hypoxia-related gene signatures for osteosarcoma diagnosis and prognosis based on WGCNA and machine learning.

Osteosarcoma (OS) is the most common primary malignant tumour of the bone with high mortality. Here, we comprehensively analysed the hypoxia signalling in OS and further constructed novel hypoxia-related gene signatures for OS prediction and prognosis. This study employed Gene Set Enrichment Analysis (GSEA), Weighted correlation network analysis (WGCNA) and Least absolute shrinkage and selection operator (LASSO) analyses to identify Stanniocalcin 2 (STC2) and Transmembrane Protein 45A (TMEM45A) as the diagnostic biomarkers, which further assessed by Receiver Operating Characteristic (ROC), decision curve analysis (DCA), and calibration curves in training and test dataset. Univariate and multivariate Cox regression analyses were used to construct the prognostic model. STC2 and metastasis were devised to forge the OS risk model. The nomogram, risk score, Kaplan Meier plot, ROC, DCA, and calibration curves results certified the excellent performance of the prognostic model. The expression level of STC2 and TMEM45A was validated in external datasets and cell lines. In immune cell infiltration analysis, cancer-associated fibroblasts (CAFs) were significantly higher in the low-risk group. And the immune infiltration of CAFs was negatively associated with the expression of STC2 (P < 0.05). Pan-cancer analysis revealed that the expression level of STC2 was significantly higher in Esophageal carcinoma (ESCA), Head and Neck squamous cell carcinoma (HNSC), Kidney renal clear cell carcinoma (KIRC), Lung squamous cell carcinoma (LUSC), and Stomach adenocarcinoma (STAD). Additionally, the higher expression of STC2 was associated with the poor outcome in those cancers. In summary, this study identified STC2 and TMEM45A as novel markers for the diagnosis and prognosis of osteosarcoma, and STC2 was shown to correlate with immune infiltration of CAFs negatively.

MTF2 facilitates the advancement of osteosarcoma through mediating EZH2/SFRP1/Wnt signaling.

BACKGROUND: Osteosarcoma is a soft tissue neoplasm with elevated recurrence risk and highly metastatic potential. Metal response element binding transcriptional factor 2 (MTF2) has been revealed to exert multiple activities in human tissues. The present research was conducted to explore the functions and related response mechanism of MTF2 in osteosarcoma which have not been introduced yet. METHODS: Bioinformatics tools identified the differential MTF2 expression in osteosarcoma tissues. MTF2 expression in osteosarcoma cells was examined with Western blot. Cell Counting Kit-8 (CCK-8) assay, 5-Ethynyl-2'-deoxyuridine (EDU) staining, wound healing as well as transwell assays measured cell proliferation, migration and invasion, respectively. Flow cytometry assay detected the cellular apoptotic level. Western blot also measured the expressions of proteins associated with epithelial mesenchymal transition (EMT), apoptosis and enhancer of zeste homolog 2 (EZH2)/secreted frizzled-related protein 1 (SFRP1)/Wnt signaling. Co-immunoprecipitation (Co-IP) assay confirmed MTF2-EZH2 interaction. RESULTS: MTF2 expression was increased in osteosarcoma tissues and cells. MTF2 interference effectively inhibited the proliferation, migration and invasion of osteosarcoma cells and promoted the cellular apoptotic rate. MTF2 directly bound to EZH2 and MTF2 silence reduced EZH2 expression, activated SFRP1 expression and blocked Wnt signaling in osteosarcoma cells. EZH2 upregulation or SFRP1 antagonist WAY-316606 partly counteracted the impacts of MTF2 down-regulation on the SFRP1/Wnt signaling and the biological phenotypes of osteosarcoma cells. CONCLUSIONS: MTF2 might down-regulate SFRP1 to activate Wnt signaling and drive the progression of osteosarcoma via interaction with EZH2 protein.

Multiple guidance mechanisms control axon growth to generate precise T-shaped bifurcation during dorsal funiculus development in the spinal cord.

The dorsal funiculus in the spinal cord relays somatosensory information to the brain. It is made of T-shaped bifurcation of dorsal root ganglion (DRG) sensory axons. Our previous study has shown that Slit signaling is required for proper guidance during bifurcation, but loss of Slit does not affect all DRG axons. Here, we examined the role of the extracellular molecule Netrin-1 (Ntn1). Using wholemount staining with tissue clearing, we showed that mice lacking Ntn1 had axons escaping from the dorsal funiculus at the time of bifurcation. Genetic labeling confirmed that these misprojecting axons come from DRG neurons. Single axon analysis showed that loss of Ntn1 did not affect bifurcation but rather altered turning angles. To distinguish their guidance functions, we examined mice with triple deletion of Ntn1, Slit1, and Slit2 and found a completely disorganized dorsal funiculus. Comparing mice with different genotypes using immunolabeling and single axon tracing revealed additive guidance errors, demonstrating the independent roles of Ntn1 and Slit. Moreover, the same defects were observed in embryos lacking their cognate receptors. These in vivo studies thus demonstrate the presence of multi-factorial guidance mechanisms that ensure proper formation of a common branched axonal structure during spinal cord development.

Unveiling the multifaceted role of adropin in various diseases (Review).

Adropin is a secreted peptide encoded by the energy homeostasis­associated gene, which also functions as a membrane­bound protein facilitating intercellular communication. This peptide has been detected in various tissues and body fluids, including the brain, liver, kidney, heart, pancreas, small intestine, endothelial cells and colostrum. Notably, the amino acid sequences of adropin are identical in humans, mice and rats. Previous studies have demonstrated that adropin levels fluctuate under different physiological and pathological conditions. Adropin plays a role in regulating carbohydrate metabolism, lipid metabolism and intercellular molecular signaling pathways, implicating its involvement in the progression of numerous diseases, such as acute myocardial infarction, lung injury, non­alcoholic fatty liver disease/non­alcoholic steatohepatitis, kidney disease, polycystic ovary syndrome, obesity, and diabetes, atherosclerosis, systemic sclerosis and cancer. Despite its significance, the precise role and mechanism of this protein remain inadequately understood and studied. To elucidate the function of adropin and its clinical research status, a systematic review of recent studies on adropin across various diseases was conducted. Additionally, several challenges and limitations associated with adropin research in both animal and clinical contexts were identified, aiming to offer valuable insights for future investigation.

LncRNAs in the Dlk1-Dio3 Domain Are Essential for Mid-Embryonic Heart Development.

The Dlk1-Dio3 domain is important for normal embryonic growth and development. The heart is the earliest developing and functioning organ of the embryo. In this study, we constructed a transcriptional termination model by inserting termination sequences and clarified that the lack of long non-coding RNA (lncRNA) expression in the Dlk1-Dio3 domain caused the death of maternal insertion mutant (MKI) and homozygous mutant (HOMO) mice starting from E13.5. Parental insertion mutants (PKI) can be born and grow normally. Macroscopically, dying MKI and HOMO embryos showed phenomena such as embryonic edema and reduced heart rate. Hematoxylin and eosin (H.E.) staining showed thinning of the myocardium in MKI and HOMO embryos. In situ hybridization (IHC) and quantitative reverse-transcription polymerase chain reaction (qRT-PCR) showed downregulation of lncGtl2, Rian, and Mirg expression in MKI and HOMO hearts. The results of single-cell RNA sequencing (scRNA-Seq) analysis indicated that the lack of lncRNA expression in the Dlk1-Dio3 domain led to reduced proliferation of epicardial cells and may be an important cause of cardiac dysplasia. In conclusion, this study demonstrates that Dlk1-Dio3 domain lncRNAs play an integral role in ventricular development.

Expression of Osteopontin and Gremlin 1 Proteins in Cardiomyocytes in Ischemic Heart Failure.

A relevant role of osteopontin (OPN) and gremlin 1 (Grem1) in regulating cardiac tissue remodeling and formation of heart failure (HF) are documented, with the changes of OPN and Grem1 levels in blood plasma due to acute ischemia, ischemic heart disease-induced advanced HF or dilatative cardiomyopathy being the primary focus in most of these studies. However, knowledge on the early OPN and Grem1 proteins expression changes within cardiomyocytes during remodeling due to chronic ischemia remains insufficient. The aim of this study was to determine the OPN and Grem1 proteins expression changes in human cardiomyocytes at different stages of ischemic HF. A semi-quantitative immunohistochemical analysis was performed in 105 myocardial tissue samples obtained from the left cardiac ventricles. Increased OPN immunostaining intensity was already detected in the stage A HF group, compared to the control group (p < 0.001), and continued to increase in the stage B HF (p < 0.001), achieving the peak of immunostaining in the stages C/D HF group (p < 0.001). Similar data of Grem1 immunostaining intensity changes in cardiomyocytes were documented. Significantly positive correlations were detected between OPN, Grem1 expression in cardiomyocytes and their diameter as well as the length, in addition to positive correlation between OPN and Grem1 expression changes within cardiomyocytes. These novel findings suggest that OPN and Grem1 contribute significantly to reorganization of cellular geometry from the earliest stage of cardiomyocyte remodeling, providing new insights into the ischemic HF pathogenesis.

Salusin­α alleviates lipid metabolism disorders via regulation of the downstream lipogenesis genes through the LKB1/AMPK pathway.

Lipid metabolism disorders are a major cause of several chronic metabolic diseases which seriously affect public health. Salusin­α, a vasoactive peptide, has been shown to attenuate lipid metabolism disorders, although its mechanism of action has not been reported. To investigate the effects and potential mechanisms of Salusin­α on lipid metabolism, Salusin­α was overexpressed or knocked down using lentiviral vectors. Hepatocyte steatosis was induced by free fatty acid (FFA) after lentiviral transfection into HepG2 cells. The degree of lipid accumulation was assessed using Oil Red O staining and by measuring several biochemical indices. Subsequently, bioinformatics was used to analyze the signaling pathways that may have been involved in lipid metabolism disorders. Finally, semi­quantitative PCR and western blotting were used to verify the involvement of the liver kinase B1 (LKB1)/AMPK pathway. Compound C, an inhibitor of AMPK, was used to confirm this mechanism's involvement further. The results showed that Salusin­α significantly attenuated lipid accumulation, inflammation and oxidative stress. In addition, Salusin­α increased the levels of LKB1 and AMPK, which inhibited the expression of sterol regulatory element binding protein­1c, fatty acid synthase and acetyl­CoA carboxylase. The addition of Compound C abrogated the Salusin­α­mediated regulation of AMPK on downstream signaling molecules. In summary, overexpression of Salusin­α activated the LKB1/AMPK pathway, which in turn inhibited lipid accumulation in HepG2 cells. This provides insights into the potential mechanism underlying the mechanism by which Salusin­α ameliorates lipid metabolism disorders while identifying a potential therapeutic target.

Development of a Novel Prognostic Panel for Colorectal Cancer Based on Cancer Functional Status, and Validation of STC2 as a Promising Biomarker.

BACKGROUND: Improving the clinical outcome of colorectal cancer (CRC) patients remains a major challenge. This study aimed to develop a new predictive classifier for CRC and to examine its relationship with the immune environment and therapeutic response. METHODS: A comprehensive bioinformatics analysis was applied to develop a risk panel comprised of cancer function status-related genes (CFSRGs). This panel was evaluated for prognostic utility by Area Under the Curve (AUC) and Kaplan-Meier (KM) analyses. Differences between high- and low-risk groups were subsequently investigated using multi-omics data. Immunohistochemistry (IHC), quantitative real-time polymerase chain reaction (qRT-PCR), and cell phenotype assays were also employed to ascertain the clinical value of STC2 expression. RESULTS: Significant differences were observed in the survival rate between high- and low-risk groups defined by our 7-CFSRG panel, both in internal and external CRC patient cohorts. The AUC for prediction of survival at 1-, 3- and 5-years was satisfactory in all cohorts. Detailed analysis revealed that tumor mutation burden, drug sensitivity, and pathological stage were closely associated with the risk score. Elevated expression of STC2 in CRC tissues relative to normal paraneoplastic tissues was associated with less favorable patient outcomes. qRT-PCR experiments confirmed that STC2 expression was significantly upregulated in several CRC cell lines (HCT116, SW480, and LOVO) compared to a normal intestinal epithelial cell line (NCM460). The proliferation, migration, and invasion of CRC cells were all significantly inhibited by knockdown of STC2. CONCLUSIONS: Our 7-CFSRG panel is a promising classifier for assessing the prognosis of CRC patients. Moreover, the targeting of STC2 may provide a novel therapeutic approach for improving patient outcomes.

Cancer Cell-Type-Dependent Modifications of Metastatic Parameters by SLIT2-ROBO1 and RHOA cAMP Signaling in Response to TGFß1 and FGF2.

The epithelial to mesenchymal transition (EMT) is a multistep process involving structural and functional alterations that are required for cancer metastasis, as well as loss of epithelial markers (e.g., E-cadherin/CDH1) and gain of mesenchymal markers (e.g., N-cadherin/CDH2, vimentin/VIM). Pathological events modify cell-cell interactions, cell-matrix adhesion and extra cellular matrix integrity leading to cell migration, evasion from the primary tumor and augmented invasiveness in the metastatic niche. This transformation is modulated by multiple paracrine factors (e.g., chemokines, growth factor), as well as SLIT2-ROBO1 signaling that collectively regulate expression of RHO GTPases (e.g., RHOA) and EMT marker genes. Yet, the roles of SLIT proteins in cancer remain enigmatic. In some cancer types, SLIT2 is anti-tumorigenic, while in other cancers it contributes towards the metastatic phenotype. Here we investigated the ambivalent metastatic activity of SLIT2 by analyzing how cAMP/RHOA signal transduction modulates SLIT-ROBO controlled metastatic parameters in response to the phosphodiesterase inhibitor IBMX (3-isobutyl-1-methylxanthine) and paracrine factors (TGF-ß/TGFß1 and FGF2). Upon SLIT2 administration cell migration and proliferation increases in colon cancer cells and decreases in cervical cancer cells, while altering cell morphology and proliferation in both cancer types. These effects are reinforced by TGF-ß/TGFß1 and FGF2, but attenuated by elevation of cAMP with IBMX, depending on the cancer cell type. Our data indicate that SLIT2 represents a potential biomarker for cancer diagnosis, prognosis, and therapy.

Targeting DKK1 enhances the antitumor activity of paclitaxel and alleviates chemotherapy-induced peripheral neuropathy in breast cancer.

Chemotherapy in combination with immunotherapy has gradually shown substantial promise to increase T cell infiltration and antitumor efficacy. However, paclitaxel in combination with immune checkpoint inhibitor targeting PD-1/PD-L1 was only used to treat a small proportion of metastatic triple-negative breast cancer (TNBC), and the clinical outcomes was very limited. In addition, this regimen cannot prevent paclitaxel-induced peripheral neuropathy. Therefore, there was an urgent need for a novel target to enhance the antitumor activity of paclitaxel and alleviate chemotherapy-induced peripheral neuropathy in breast cancer. Here, we found that Dickkopf-1 (DKK1) expression was upregulated in multiply subtypes of human breast cancer specimens after paclitaxel-based chemotherapy. Mechanistic studies revealed that paclitaxel promoted DKK1 expression by inducing EGFR signaling in breast cancer cells, and the upregulation of DKK1 could hinder the therapeutic efficacy of paclitaxel by suppressing the infiltration and activity of CD8+ T cells in tumor microenvironment. Moreover, paclitaxel treatment in tumor-bearing mice also increased DKK1 expression through the activation of EGFR signaling in the primary sensory dorsal root ganglion (DRG) neurons, leading to the development of peripheral neuropathy, which is charactered by myelin damage in the sciatic nerve, neuropathic pain, and loss of cutaneous innervation in hindpaw skin. The addition of an anti-DKK1 antibody not only improved therapeutic efficacy of paclitaxel in two murine subtype models of breast cancer but also alleviated paclitaxel-induced peripheral neuropathy. Taken together, our findings providing a potential chemoimmunotherapy strategy with low neurotoxicity that can benefit multiple subtypes of breast cancer patients.

Molecular analysis of a self-organizing signaling pathway for Xenopus axial patterning from egg to tailbud.

Xenopus embryos provide a favorable material to dissect the sequential steps that lead to dorsal-ventral (D-V) and anterior-posterior (A-P) cell differentiation. Here, we analyze the signaling pathways involved in this process using loss-of-function and gain-of-function approaches. The initial step was provided by Hwa, a transmembrane protein that robustly activates early ß-catenin signaling when microinjected into the ventral side of the embryo leading to complete twinned axes. The following step was the activation of Xenopus Nodal-related growth factors, which could rescue the depletion of ß-catenin and were themselves blocked by the extracellular Nodal antagonists Cerberus-Short and Lefty. During gastrulation, the Spemann-Mangold organizer secretes a cocktail of growth factor antagonists, of which the BMP antagonists Chordin and Noggin could rescue simultaneously D-V and A-P tissues in ß-catenin-depleted embryos. Surprisingly, this rescue occurred in the absence of any ß-catenin transcriptional activity as measured by ß-catenin activated Luciferase reporters. The Wnt antagonist Dickkopf (Dkk1) strongly synergized with the early Hwa signal by inhibiting late Wnt signals. Depletion of Sizzled (Szl), an antagonist of the Tolloid chordinase, was epistatic over the Hwa and Dkk1 synergy. BMP4 mRNA injection blocked Hwa-induced ectopic axes, and Dkk1 inhibited BMP signaling late, but not early, during gastrulation. Several unexpected findings were made, e.g., well-patterned complete embryonic axes are induced by Chordin or Nodal in ß-catenin knockdown embryos, dorsalization by Lithium chloride (LiCl) is mediated by Nodals, Dkk1 exerts its anteriorizing and dorsalizing effects by regulating late BMP signaling, and the Dkk1 phenotype requires Szl.

Study on the role of MYCN in retinoblastoma by inhibiting p53 and activating wnt/ßcatenin/Fra-1 signaling pathway by reducing DKK3.

Retinoblastoma (RB) is a pediatric malignancy, typically diagnosed at birth or during early childhood. The pathogenesis of RB is marked by the amplification of the Basic Helix-Loop-Helix (BHLH) Transcription Factor MYCN, which serves as a transcriptional regulator capable of binding to Dickkopf 3 (DKK3). However, the precise role of DKK3 in the malignant progression of RB cells caused by MYCN remains elusive. In the present study, the expression of MYCN was either overexpressed or interfered in RB cells. Subsequently, the expression level of DKK3 was assessed through quantitative real-time polymerase chain reaction and western blot analysis. Cell proliferation was evaluated using the Cell Counting Kit-8 assay and 5-ethynyl-2'-deoxyuridine staining, while cell cycle progression and apoptosis were analyzed by flow cytometry and western blot analysis, respectively. Additionally, the expression of proteins involved in the Wnt/ß-catenin/Fra-1/p53 signaling pathway was evaluated via western blot analysis. To gain further insights, Wnt agonists and the P53 inhibitor PFT-α were introduced into exploration. The current investigation revealed a negative correlation between the expression levels of MYCN and DKK3 in RB cells. Additionally, DKK3 overexpression inhibited cell proliferation, promoted cell apoptosis, and arrested cell cycle in RB cells with high expression of MYCN. Moreover, enhanced DKK3 expression inhibited proliferation, promoted cell cycle arrest and apoptosis of RB cells by modulating the wnt/ßcatenin/Fra-1/p53 signaling pathway. Furthermore, in vivo experiments revealed that overexpression of DKK3 inhibits the growth of RB tumors. Collectively, our findings elucidate that MYCN stimulates the Wnt/ß-catenin/Fra-1 pathway by suppressing DKK3 expression, ultimately suppressing p53 activity and contributing to malignant progression of RB.

Role of sclerostin deletion in bisphosphonate-induced osteonecrosis of the jaw.

PURPOSE: Bone resorption inhibitors, such as bisphosphonates (BP) and denosumab, are frequently used for the management of osteoporosis. Although both drugs reduce the risk of osteoporotic fractures, they are associated with a serious side effect known as medication-related osteonecrosis of the jaw (MRONJ). Sclerostin antibodies (romosozumab) increase bone formation and decrease the risk of osteoporotic fractures: however, their anti-resorptive effect increases ONJ. Thus, this study aimed to elucidate the role of sclerostin deletion in the development of MRONJ. METHODS: Sclerostin knockout (SostΔ26/Δ26) mice were used to confirm the development of ONJ by performing tooth extractions. To confirm the role of sclerostin deficiency in a more ONJ-prone situation, we used the BP-induced ONJ model in combination with severe periodontitis to evaluate the development of ONJ and bone formation in wild-type (WT) and SostΔ26/Δ26 mice. Wound healing assay using gingival fibroblasts with or without sclerostin stimulation and tooth extraction socket healing were evaluated in the WT and SostΔ26/Δ26 mice. RESULTS: ONJ was not detected in the extraction socket of SostΔ26/Δ26 mice. Moreover, the incidence of ONJ was significantly lower in the SostΔ26/Δ26 mice treated with BP compared to that of the WT mice. Osteogenic proteins, osteocalcin, and runt-related transcription factor 2, were expressed in the bone surface in SostΔ26/Δ26 mice. Recombinant sclerostin inhibited gingival fibroblast migration. The wound healing rate of the extraction socket was faster in SostΔ26/Δ26 mice than in WT mice. CONCLUSION: Sclerostin deficiency did not cause ONJ and reduced the risk of developing BP-induced ONJ. Enhanced bone formation and wound healing were observed in the tooth extraction socket. The use of romosozumab (anti-sclerostin antibody) has proven to be safe for surgical procedures of the jaw.

Neural progenitor-derived Apelin controls tip cell behavior and vascular patterning.

During angiogenesis, vascular tip cells guide nascent vascular sprouts to form a vascular network. Apelin, an agonist of the G protein-coupled receptor Aplnr, is enriched in vascular tip cells, and it is hypothesized that vascular-derived Apelin regulates sprouting angiogenesis. We identify an apelin-expressing neural progenitor cell population in the dorsal neural tube. Vascular tip cells exhibit directed elongation and migration toward and along the apelin-expressing neural progenitor cells. Notably, restoration of neural but not vascular apelin expression in apelin mutants remedies the angiogenic defects of mutants. By functional analyses, we show the requirement of Apelin signaling for tip cell behaviors, like filopodia formation and cell elongation. Through genetic interaction studies and analysis of transgenic activity reporters, we identify Apelin signaling as a modulator of phosphoinositide 3-kinase and extracellular signal-regulated kinase signaling in tip cells in vivo. Our results suggest a previously unidentified neurovascular cross-talk mediated by Apelin signaling that is important for tip cell function during sprouting angiogenesis.

Stanniocalcin-2 expression in glioblastoma - A novel prognostic biomarker: An observational study.

The objective of this study was to assess the prognostic relevance of Stanniocalcin-2 (STC2) expression, as determined via immunohistochemistry in tumor tissue, in a cohort of 83 patients diagnosed with glioblastoma who underwent maximal safe surgical resection followed by radiotherapy concurrent with adjuvant temozolomide. STC2 expression levels were categorized using a 3-tiered semiquantitative system: negative expression (level 0-), low expression (level 1+), and high expression (levels 2 + and 3+). Patients were categorized into 2 distinct groups according to their STC2 expression levels: negative STC2 (-/+) and positive STC2 (++/+++). The primary outcome measure was the relationship between STC2 expression and progression-free survival (PFS), with overall survival (OS) serving as the secondary endpoint. Kaplan-Meier survival analysis confirmed that patients exhibiting high STC2 expression had significantly shorter OS (8 vs 20 months, P < .001) and PFS (6 vs 18 months, P < .001) than those with low or negative STC2 expression. Multivariate analysis revealed that STC2 expression was an independent prognostic factor for both OS (hazard ratio: 0.4; 95% confidence interval: 0.2-0.8; P < .05) and PFS (hazard ratio: 0.3; 95% confidence interval: 0.2-0.4; P < .05) in patients with glioblastoma. Furthermore, elevated STC2 expression in GBM was correlated with several established aggressive clinicopathological characteristics, including advanced age (≥65 years), low ECOG PS (≥2), and isocitrate dehydrogenase mutation negativity. These findings underscore that heightened STC2 expression within the tumor tissue of GBM patients functions as an adverse prognostic marker, correlating with an elevated risk of progression and reduced OS. Therapeutic interventions targeting the AKT-mTOR, ERK1-2, and mitogen-activated protein kinase pathways as well as immune checkpoint inhibitors and vascular endothelial growth factor blockade, as well as potential forthcoming antibody-drug conjugates targeting the STC2 molecule, have the potential to broaden the scope of combined treatment strategies.

Cancer-wide in silico analyses using differentially expressed genes demonstrate the functions and clinical relevance of JAG, DLL, and NOTCH.

Notch ligands [jagged (JAG) and, delta-like (DLL) families] and receptors [NOTCH family] are key regulators of Notch signaling. NOTCH signaling contributes to vascular development, tissue homeostasis, angiogenesis, and cancer progression. To elucidate the universal functions of the JAG, DLL, and NOTCH families and their connections with various biological functions, we examined 15 types of cancer using The Cancer Genome Atlas clinical database. We selected the differentially expressed genes (DEGs), which were positively correlated to the JAG, DLL, and NOTCH families in each cancer. We selected positive and negative hallmark signatures across cancer types. These indicated biological features associated with angiogenesis, hypoxia, KRAS signaling, cell cycle, and MYC targets by gene ontology and gene set enrichment analyses using DEGs. Furthermore, we analyzed single-cell RNA sequencing data to examine the expression of JAG, DLL, and NOTCH families and enrichment of hallmark signatures. Positive signatures identified using DEGs, such as KRAS signaling and hypoxia, were enriched in clusters with high expression of JAG, DLL, and NOTCH families. We subsequently validated the correlation between the JAG, DLL, and NOTCH families and clinical stages, including treatment response, metastasis, and recurrence. In addition, we performed survival analysis to identify hallmark signatures that critically affect patient survival when combining the expression of JAG, DLL, and NOTCH families. By combining the DEG enrichment and hallmark signature enrichment in survival analysis, we suggested unexplored regulatory functions and synergistic effects causing synthetic lethality. Taken together, our observations demonstrate the functions of JAG, DLL, and NOTCH families in cancer malignancy and provide insights into their molecular regulatory mechanisms.