Specific lipid magnetic sphere sorted CD146-positive bone marrow mesenchymal stem cells can better promote articular cartilage damage repair.

BACKGROUND: The characteristics and therapeutic potential of subtypes of bone marrow mesenchymal stem cells (BMSCs) are largely unknown. Also, the application of subpopulations of BMSCs in cartilage regeneration remains poorly characterized. The aim of this study was to explore the regenerative capacity of CD146-positive subpopulations of BMSCs for repairing cartilage defects. METHODS: CD146-positive BMSCs (CD146 + BMSCs) were sorted by self-developed CD146-specific lipid magnetic spheres (CD146-LMS). Cell surface markers, viability, and proliferation were evaluated in vitro. CD146 + BMSCs were subjected to in vitro chondrogenic induction and evaluated for chondrogenic properties by detecting mRNA and protein expression. The role of the CD146 subpopulation of BMSCs in cartilage damage repair was assessed by injecting CD146 + BMSCs complexed with sodium alginate gel in the joints of a mouse cartilage defect model. RESULTS: The prepared CD146-LMS had an average particle size of 193.7 ± 5.24 nm, an average potential of 41.9 ± 6.21 mv, and a saturation magnetization intensity of 27.2 Am2/kg, which showed good stability and low cytotoxicity. The sorted CD146 + BMSCs highly expressed stem cell and pericyte markers with good cellular activity and cellular value-added capacity. Cartilage markers Sox9, Collagen II, and Aggrecan were expressed at both protein and mRNA levels in CD146 + BMSCs cells after chondrogenic induction in vitro. In a mouse cartilage injury model, CD146 + BMSCs showed better function in promoting the repair of articular cartilage injury. CONCLUSION: The prepared CD146-LMS was able to sort out CD146 + BMSCs efficiently, and the sorted subpopulation of CD146 + BMSCs had good chondrogenic differentiation potential, which could efficiently promote the repair of articular cartilage injury, suggesting that the sorted CD146 + BMSCs subpopulation is a promising seed cell for cartilage tissue engineering.

[Comparative study on the degradation rate and regulatory effects of two resorbable collagen membranes during the in vivo implantation].

Objective: To explore the differences in the performance and tissue repair promotion effects of small intestinal submucosa membrane (SIS membrane) and Bio-Gide resorbable collagen membrane (Bio-Gide membrane) by performing the subcutaneous implantation models in mice. Methods: For in vivo studies, we stablished membrane implantation models using 6-8 week-old male C57BL/6 mice. The degradation rates were explored through HE staining analysis at different time points (1, 3, 5, 7, 14 and 28 d, 3 mice/group/time point). The influences of the two membranes on local macrophages and neovasculum were evaluated by immunofluorescence detection of F4/80 and CD31, and the mobilization effects of the two membranes on local stem cells were evaluated by immunohistochemical detection of Ki67 and CD146. For in vitro studies, mice periodontal ligament stem cells (mPDLSCs) were co-cultured with these two membrane materials, and the cell morphologies were observed by scanning electron microscopy. In addition, the gene expressions of Ki67, Cxcl1, Ccl1, Tnfa were investigated by real-time fluorescence quantitative PCR (RT-qPCR). Results: The results of in vivo studies showed that by day 28, there was no significant difference in degradation rate between these two membrane materials [SIS degradation rate: (16.84±4.00) %, Bio-Gide degradation rate: (24.07±3.97) %, P=0.090], illustrating that both of them could maintain the barrier effects for more than one month. In addition, there was no significant difference in the infiltration number of local F4/80 positive macrophages between these two groups by the day 3 after implantation [SIS: (20.67±5.69) cells/visual field, Bio-Gide: (25.33±2.52) cells/visual field, P=0.292]. However, compared with the Bio-Gide membrane, SIS membrane significantly promoted local CD31+vascular regeneration [SIS: (4.67±1.15) cells/visual field, Bio-Gide: (1.00±1.00) cells/visual field, P=0.015] and CD146+stem cell recruitment [SIS: (22.33±4.16) cells/visual field, Bio-Gide: (11.33±2.52) cells/visual field, P=0.025]. The RT-qPCR results also showed that SIS membrane promoted the gene expression of Cxcl1 (SIS vs Bio-Gide P<0.001) in mPDLSCs, but had no effect on the gene expression of Tnfa (SIS vs Bio-Gide P=0.885). Conclusions: SIS membrane showed a similar degradation rate compared with Bio-Gide membrane, and there was no significant difference in the effects of these two membranes on local inflammation or macrophages. Therefore, both of these membranes could meet the barrier effects required by guided tissue regeneration.

CD146 as a prognostic marker in breast cancer: A meta-analysis.

BACKGROUND: CD146, a cell adhesion molecule, was first discovered in melanoma. Since then, it has been established as a promoter of tumor progression and metastasis. Many recent clinical studies have associated CD146 overexpression with poor prognosis in various cancers. However, clinical relevance of CD146 in prognosis of breast cancer has been poorly studied. METHODS: We performed meta-analysis of data of all clinical studies associated with the prognostic value of CD146 expression in breast cancer. Relevant studies were retrieved from PubMed database as per the inclusion and exclusion criteria, data were extracted independently and carefully by two reviewers with the help of standardized form, and meta-analysis was performed to correlate CD146 expression with molecular subtypes, lymph node metastasis, and overall survival in breast cancer. RESULTS: Our findings suggest that CD146 expression is predominantly found in triple-negative breast cancer subtype (pooled odds ratio = 2.98, 95% confidence interval [CI] =2.19-4.05, P < .00001) and breast tumors overexpressing CD146 have a higher risk of lymph node metastasis (pooled relative risk = 1.64, 95% CI = 1.44-1.87, P < .00001). Furthermore, high expression of CD146 was associated with poor prognosis in breast cancer (pooled hazard ratio = 1.51, 95% CI = 1.21-1.87, P = .0002). CONCLUSION: Overall results suggested that CD146 may be a potential prognostic marker to predict metastatic potential and disease outcomes in breast cancer and can be used as a therapeutic target.

CD146+CAFs promote progression of endometrial cancer by inducing angiogenesis and vasculogenic mimicry via IL-10/JAK1/STAT3 pathway.

Heterogeneous cancer-associated fibroblasts (CAFs) play important roles in cancer progression. However, the specific biological functions and regulatory mechanisms involved in endometrial cancer have yet to be elucidated. We aimed to explore the potential mechanisms of heterogeneous CAFs in promoting endometrial cancer progression. The presence of melanoma cell adhesion molecule (MCAM; CD146) positive CAFs was confirmed by tissue multi-immunofluorescence (mIF), and fluorescence activated cell sorting (FACS). The biological functions were determined by wound healing assays, tuber formation assays and cord formation assays. The effects of CD146+CAFs on endometrial cancer cells were studied in vitro and in vivo. The expression level of interleukin 10 (IL-10) was measured by quantitative real time polymerase chain reaction (qRT-PCR), western boltting and enzyme linked immunosorbent assays (ELISAs). In addition, the transcription factor STAT3 was identified by bioinformatics methods and chromatin immunoprecipitation (ChIP). A subtype of CAFs marked with CD146 was found in endometrial cancer and correlated with poor prognosis. CD146+CAFs promoted angiogenesis and vasculogenic mimicry (VM) in vitro. A xenograft tumour model also showed that CD146+CAFs can facilitate tumour progression. The expression of IL-10 was elevated in CD146+CAFs. IL-10 promoted epithelial-endothelial transformation (EET) and further VM formation in endometrial cancer cells via the janus kinase 1/signal transducer and activator of transcription 3 (JAK1/STAT3) signalling pathway. This process could be blocked by the JAK1/STAT3 inhibitor niclosamide. Mechanically, STAT3 can bind to the promoter of cadherin5 (CDH5) to promote its transcription which may be stimulated by IL-10. We concluded that CD146+CAFs could promote angiogenesis and VM formation via the IL-10/JAK1/STAT3 signalling pathway. These findings may lead to the identification of potential targets for antiangiogenic therapeutic strategies for endometrial cancers.

The role of CD146 in renal disease: from experimental nephropathy to clinics.

Vascular endothelial dysfunction is a major risk factor in the development of renal diseases. Recent studies pointed out a major interest for the inter-endothelial junction protein CD146, as its expression is modulated during renal injury. Indeed, some complex mechanisms involving this adhesion molecule and its multiple ligands are observed in a large number of renal diseases in fundamental or clinical research. The purpose of this review is to summarize the most recent literature on the role of CD146 in renal pathophysiology, from experimental nephropathy to clinical trials.

Cooperative polarization of MCAM/CD146 and ERM family proteins in melanoma.

The WRAMP structure is a protein network associated with tail-end actomyosin contractility, membrane retraction, and directional persistence during cell migration. A marker of WRAMP structures is melanoma cell adhesion molecule (MCAM) which dynamically polarizes to the cell rear. However, factors that mediate MCAM polarization are still unknown. In this study, BioID using MCAM as bait identifies the ERM family proteins, moesin, ezrin, and radixin, as WRAMP structure components. We also present a novel image analysis pipeline, Protein Polarity by Percentile ("3P"), which classifies protein polarization using machine learning and facilitates quantitative analysis. Using 3P, we find that depletion of moesin, and to a lesser extent ezrin, decreases the proportion of cells with polarized MCAM. Furthermore, although copolarized MCAM and ERM proteins show high spatial overlap, 3P identifies subpopulations with ERM proteins closer to the cell periphery. Live-cell imaging confirms that MCAM and ERM protein polarization is tightly coordinated, but ERM proteins enrich at the cell edge first. Finally, deletion of a juxtamembrane segment in MCAM previously shown to promote ERM protein interactions impedes MCAM polarization. Our findings highlight the requirement for ERM proteins in recruitment of MCAM to WRAMP structures and an advanced computational tool to characterize protein polarization.

CD146/MCAM links doxorubicin-induced epigenetic dysregulation to the impaired fatty acid transportation in H9c2 cardiomyoblasts.

CD146/MCAM has garnered significant attention for its potential contribution to cardiovascular disease; however, the transcriptional regulation and functions remain unclear. To explore these processes regarding cardiomyopathy, we employed doxorubicin, a widely used stressor for cardiomyocytes. Our in vitro study on H9c2 cardiomyoblasts highlights that, besides impairing the fatty acid uptake in the cells, doxorubicin suppressed the expression of fatty acid binding protein 4 (Fabp4) along with the histone deacetylase 9 (Hdac9), bromodomain and extra-terminal domain proteins (BETs: Brd2 and Brd4), while augmented the production of CD146/MCAM. Silencing and chemical inhibition of Hdac9 further augmented CD146/MCAM and deteriorated fatty acid uptake. In contrast, chemical inhibition of BETs as well as silencing of MCAM/CD146 ameliorated fatty acid uptake. Moreover, protein kinase C (PKC) inhibition abrogated CD146/MCAM, particularly in the nucleus. Taken together, our results suggest that epigenetic dysregulation of Hdac9, Brd2, and Brd4 alters CD146/MCAM expression, deteriorating fatty acid uptake by downregulating Fabp4. This process depends on the PKC-mediated nuclear translocation of CD146. Thus, this study highlights a pivotal role of CD146/MCAM in doxorubicin-induced cardiomyopathy.

CD146 deficiency aggravates chronic obstructive pulmonary disease via the increased production of S100A9 and MMP-9 in macrophages.

Chronic obstructive pulmonary disease (COPD) is a leading cause of global death. As a molecule beyond adhesion, CD146 is involved in COPD pathogenesis. However, the mechanisms of CD146 in COPD remain largely elusive. We hypothesized that CD146 regulates the production of matrix metalloproteinase-9 (MMP-9) in macrophages and thereby contributes to COPD. Here, we constructed a murine model of COPD using lipopolysaccharide (LPS) and porcine pancreatic elastase (PPE). In COPD-like mice, LPS and PPE decreased the pulmonary expression of CD146. MMP-9 expression and bioactivity were increased in CD146 knockout COPD-like mice. In vitro, LPS decreased CD146 expression in macrophages. With or without LPS challenge, CD146-defective macrophages produced more MMP-9. Transcriptome analysis based on next-generation sequencing (NGS) revealed that S100A9 regulated MMP-9 production in CD146-defective macrophages. Targeting S100A9 with paquinimod decreased lung inflammation and alleviated alveolar destruction in COPD-like mice. Collectively, our study suggests that CD146 negatively regulates MMP-9 production in macrophages via the S100A9 pathway in COPD.

A Model of Immediate Implant Placement to Evaluate Early Osseointegration in 129/Sv Diabetic Mice.

PURPOSE: To analyze the process of early oral osseointegration of titanium (Ti) implants in diabetic 129/Sv mice through microCT and histologic and immunohistochemical analysis. MATERIALS AND METHODS: A group of 30 male 129/Sv mice was equally subdivided into two groups: (1) nondiabetic (ND), in which mice did not undergo systemic alterations and received a standard diet, and (2) diabetic (D), in which mice were provided a high-fat diet from the age of 6 weeks until the conclusion of the study and received two intraperitoneal (IP) injections of streptozotocin (STZ) at a concentration of 100 mg/Kg each. Each mouse underwent extraction of a maxillary first molar, and customized Ti screws (0.50 mm diameter, 1.5 mm length) were placed in the residual alveolar sockets of the palatal roots. At 7 and 21 days after implant placement, the animals were euthanized for maxilla and pancreas collection. Maxillae containing Ti implants were analyzed with microCT, histology, and immunohistochemistry for cells that were positive for F4/80, CD146, runt-related transcription factor 2 (Runx2), and proliferating cell nuclear antigen (PCNA). Pancreata were histologically analyzed. Quantitative data were statistically analyzed with a significance level at 5% (P < .05). RESULTS: ND mice presented successful healing and osseointegration, with a significantly higher fraction of bone volume compared to D mice, both at the alveolar sockets (53.39 ± 5.93 and 46.08 ± 3.18, respectively) and at the implant sites (68.88 ± 7.07 and 44.40 ± 6.98, respectively) 21 days after implant placement. Histologic evaluation revealed that the ND mice showed a significant decrease in inflammatory infiltrate and a significant increase in newly formed bone matrix at 21 days, whereas peri-implant sites in the D mice were predominantly encapsulated by fibrous tissue and chronic inflammatory infiltrate. Immunohistochemical characterization revealed higher Runx2 osteoblast differentiation and higher cell proliferation activity in the ND mice at 7 days, while higher amounts of macrophages were present in D mice at 7 and 21 days. Interestingly, no differences were found in CD146-positive cells when comparing ND and D mice. CONCLUSIONS: This study evaluated the effects of immediate dental implant placement in 129/Sv diabetic mice by using specific healing markers to identify changes in cellular events involved in early oral osseointegration. This approach may serve as tool to evaluate new materials and surface coatings to improve osseointegration in diabetic patients.

CD146-positive adipose-derived stem cells subpopulation enriched by albumin magnetic sphere ameliorates knee osteoarthritis pain and promotes cartilage repair.

BACKGROUND: The use of adipose stem cell (ADSCs) subpopulations in cartilage repair remains poorly characterized. In this study, we constructed an albumin magnetic sphere with specific targeting of CD146 (CD146-AMs) for sorting a subpopulation of CD146-positive ADSCs (CD146 + ADSCs) and explored the role of CD146 + ADSCs on joint pain and cartilage repair in rats with knee osteoarthritis (KOA). METHODS: CD146-AMs were prepared and analyzed in materialistic characterization tests. Subpopulations of CD146 + ADSCs were sorted using CD146-AMs. Surface labeling, viability, and proliferation of a subpopulation of CD146 + ADSCs were evaluated in vitro. Molecular characterization of mRNA and protein expression profiles was analyzed by microarray. A rat KOA pain model was established by the iodoacetic acid method, and KOA pain and the promotion of cartilage repair were assessed after treatment with bilateral joint cavity injections of CD146 + ADSCs. RESULTS: The CD146-AMs prepared in this study had an average particle size of 242.63 ± 6.74 nm, an average potential of 33.82 ± 3.53 mv, and high CD146 targeting and low cytotoxicity. The positive rate of enriched CD146 + ADSCs was 98.21% and showed a high level of stem cell marker expression and good cell viability. Gene and protein expression profiles showed that CD146 + ADSCs have different cellular functions, especially in regulating inflammation. In the KOA model, low, medium and high concentrations of CD146 + ADSCs were able to improve KOA pain and promote cartilage repair in a concentration-dependent trend. CONCLUSIONS: The CD146-AMs prepared in this study were able to safely and efficiently sort out the CD146 + ADSCs subpopulation. The subpopulation of CD146 + ADSCs has a unique molecular profile that ameliorates KOA pain and repairs cartilage damage in rats, providing a new idea for KOA treatment.

Investigating changes in the post-transcriptional pattern of VEGF and CD146 genes carrying miR-573 in breast cancer cells treated with tamoxifen.

BACKGROUND: Recent developments regarding the contribution of microRNAs (miRNAs) to tumor angiogenesis and the oncogenic effects of miRNAs point to their potential role in breast cancer angiogenesis. Tumor-derived exosomes are considered a rich source of miRNAs that can regulate the function of other cells in the tumor microenvironment, including vascular endothelial cells. This study analyzes the effect of tamoxifen chemotherapy on the expression of a key miRNA, miR-573, involved in the angiogenesis of the tumor exosomes and introduces a regulatory link between this miRNA and the CD146 gene associated with the vascular endothelial growth factor (VEGF) messaging pathway. MATERIALS AND METHODS: MCF-7 breast cancer cells were purchased and cultured in a complete culture medium. These cells were treated with tamoxifen and then their exosomes were extracted from the culture medium. The RNAs of the exosomes were isolated and the expression of miR-573, VEGF, and CD146 genes in the exosomes was investigated using the real-time polymerase chain reaction (PCR) method. RESULTS: The results of this study showed that tamoxifen treatment increased the expression of miR-573 in exosomes derived from MCF-7 cancer cells. The expression of CD146 and VEGF genes in drug-treated cell exosomes had a downward pattern. CONCLUSION: The results of this experiment demonstrated that the treatment of breast cancer cells with tamoxifen reduces the expression of VEGF and CD146 by increasing miR-573. Thus, angiogenesis is reduced and, therefore, its anti-tumor effects are applied.

The influence of inflammation on the characteristics of adipose-derived mesenchymal stem cells (ADMSCs) and tissue repair capability in a hepatic injury mouse model.

BACKGROUND: Mesenchymal stem cells (MSCs) are adult stem cells with self-renewal and multi-directional differentiation potential and possess the functions of immunomodulation, regulation of cell growth, and repair of damage. Over recent years, MSCs have been found to regulate the secretion of inflammatory factors and to exert regulatory effects on various lymphocytes in inflammatory states, and on the subsequent repair of tissue damage caused by inflammation. In the present study, we analyzed the effects of tissue inflammation on the characteristics of MSCs. METHODS: Human fat derived from the infrapatellar fat pad (IPFP) of knees with differing degrees of inflammation was extracted from specimens derived from total knee arthroplasties. HE and immunohistochemical staining was performed to directly observe the evidence and degree of inflammation in human infrapatellar fat pad tissue in order to classify MSCs cells, by their origin, into highly inflamed and lowly inflamed groups, and to study the effect of tissue inflammation on cell acquisition rates via cellular counting data. Flow cytometry assays were performed to investigate the effect of tissue inflammation on MSC surface marker expression. Trilineage differentiation, including osteogenesis, adipogenesis, and chondrogenesis, was performed to assess the effect of tissue inflammation on the ability of MSCs to undergo directed differentiation. The effect of tissue inflammation on the ability of MSCs to proliferate was investigated via clone formation studies. RNA-sequencing was performed to evaluate the transcriptomes of MSCs derived from different areas of inflammation. The effect of tissue inflammation on tissue repair capacity and safety of MSCs was investigated via a murine model of acute liver injury. RESULTS: The results of cell count data indicate that a high degree of tissue inflammation significantly decreases the acquisition rate of MSCs, and the proportion of CD34+ and CD146+ cells. The results of our trilineage differentiation assay show that a higher degree of inflammation decreases osteogenic differentiation and enhances adipogenic and chondrogenic differentiation of MSCs. However, these differences were not statistically significant. Clone formation assays indicate that the degree of tissue inflammation at the MSC source does not significantly affect the proliferative capacity of MSCs. The transcriptomes of MSCs remain relatively stable in fat pad tissues derived from both highly and lowly inflamed samples. The results of acute liver injury investigations in mice indicate that MSCs of high and low inflammatory tissue origin have no significant difference in their tissue repair capability. CONCLUSIONS: High tissue inflammation at the source of MSCs reduces the acquisition rate of MSCs and the percentage of CD34+ and CD146+ cells acquisition. However, source tissue inflammation may not significantly affect trilineage differentiation potential and proliferative capacity of MSCs. Also, MSCs obtained from differing source degrees of inflammation retain stable and similar transcriptomic profile and are both safe and efficacious for tissue repair/regeneration without detectable differences.

Expression profiles of human somatic mesenchymal stem cells derived from fresh endometrium, ectopic-endometrium and umbilical cord.

OBJECTIVES: The study investigated the stem cell expression profiles and differentiation capacities of mesenchymal stem cells (MSCs) from different tissues, specifically human eutopic endometrium MSCs (eut-MSCs), ectopic endometrium MSCs (ect-MSCs), and umbilical cord MSCs (UC-MSCs). Our aim was to identify any similarities in subpopulations among these MSCs and lay a foundation for MSCs repair. MATERIAL AND METHODS: MSCs were isolated from endometrial tissue (n = 5), endometriosis tissue (n = 6), and umbilical cords (n = 7). Flow cytometry was used to examine cell phenotype, and three lineage tests were conducted to evaluate the differentiation capacity of the MSCs. RESULTS: Eut-MSCs expressed CD44 (98.00 ± 0.96%), CD73 (99.54 ± 0.02%), CD140b (99.16 ± 0.50%), CD146 (93.87 ± 2.27%), SUSD2 (50.76 ± 8.15%), and CD271 (2.1 ± 1.22%). Ect-MSCs expressed CD44 (98.23 ± 1.60%), CD73 (99.63 ± 0.04%), CD140b (98.13 ± 0.53%), CD146 (93.88 ± 3.19%), SUSD2 (49.33 ± 6.36%), and CD271 (2.85 ± 1.17%). UC-MSCs expressed CD44 (99.11 ± ± 0.42%), CD73 (99.65 ± 0.12%), CD140b (99.84 ± 0.42%), CD146 (88.09 ± 4.20%), SUSD2 (72.87 ± 7.13%), and CD271 (6.19 ± 2.08%). The expression of SUSD2 and CD271 in UC-MSCs was slightly but not significantly higher than that in ect-MSCs and eut-MSCs. However, CD44, CD73, CD140b, and CD146 showed similar expression levels in UC-MSCs, ect-MSCs, and eut-MSCs. All three types of MSCs demonstrated the capacity to differentiate into osteoblasts, adipocytes, and chondrocytes. CONCLUSIONS: Our findings indicate that ect-MSCs, eut-MSCs, and UC-MSCs have similar stem cell phenotypes and the ability to differentiate into three lineages.

CD146 promotes malignant progression of breast phyllodes tumor through suppressing DCBLD2 degradation and activating the AKT pathway.

BACKGROUND: As a rapid-progressing tumor, breast malignant phyllodes tumors (PTs) are challenged by the lack of effective therapeutic strategies and suitable prognostic markers. This study aimed to clarify the role and mechanism of CD146 on promoting PTs malignant progression, and to identify a novel prognosis marker and treatment target of breast malignant PTs. METHODS: The expression and prognostic significance of CD146 in PTs was detected through single-cell RNA-sequencing (scRNA-seq), immunostaining, real-time PCR and other methodologies. Functional experiments including proliferation assay, colony formation assay, transwell assay, and collagen contraction assay were conducted to validate the role of CD146 in malignant progression of PTs. The efficacy of anti-CD146 monoclonal antibody AA98 against malignant PTs was corroborated by a malignant PT organoid model and a PT patient-derived xenograft (PDX) model. Transcriptome sequencing, proteomic analysis, co-immunoprecipitation, and pull-down assay was employed to identify the modulating pathway and additional molecular mechanism. RESULTS: In this study, the scRNA-seq analysis of PTs disclosed a CD146-positive characteristic in the α-SMA+ fibroblast subset. Furthermore, a progressive elevation in the level of CD146 was observed with the malignant progression of PTs. More importantly, CD146 was found to serve as an independent predictor for recurrence in PT patients. Furthermore, CD146 was found to augment the viability and invasion of PTs. Mechanistically, CD146 acted as a protective "shield" to prevent the degradation of Discoidin, CUB, and LCCL domain-containing protein 2 (DCBLD2), thereby activating the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway and enhancing malignant behaviors of PT cells. In the malignant PT organoid and PDX model, a significant suppression of malignant PT growth was observed after the application of AA98. CONCLUSIONS: These findings suggested that CD146 served as an efficacious marker for predicting PT malignant progression and showed promise as a prognosis marker and treatment target of breast malignant PTs. The study further unveiled the essential role of the CD146-DCBLD2/PI3K/AKT axis in the malignant progression of PTs.

Targeted Delivery of RGD-CD146+CD271+ Human Umbilical Cord Mesenchymal Stem Cell-Derived Exosomes Promotes Blood-Spinal Cord Barrier Repair after Spinal Cord Injury.

Spinal cord injury (SCI) disrupts the blood-spinal cord barrier (BSCB), potentially exacerbating nerve damage and emphasizing the criticality of preserving the BSCB integrity during SCI treatment. This study explores an alternative therapeutic approach for SCI by identifying a subpopulation of exosomes with stable BSCB function and achieving a specific targeted delivery. Specific subpopulations of CD146+CD271+ umbilical cord mesenchymal stem cells (UCMSCs) were isolated, from which engineered exosomes (RGD-CD146+CD271+ UCMSC-Exos) with targeted neovascularization function were obtained through gene transfection. In vivo and in vitro experiments were performed to explore the targeting and therapeutic effects of RGD-CD146+CD271+ UCMSC-Exos and the potential mechanisms underlying BSCB stabilization and neural function recovery. The results demonstrated that RGD-CD146+CD271+ UCMSC-Exos exhibited physical and chemical properties similar to those of regular exosomes. Notably, following intranasal administration, RGD-CD146+CD271+ UCMSC-Exos exhibited enhanced aggregation at the SCI center and demonstrated the specific targeting of neovascular endothelial cells. In the SCI model, intranasal administration of RGD-CD146+CD271+ UCMSC-Exos reduced Evans blue dye leakage, increased tight junction protein expression, and improved neurological function recovery. In vitro testing revealed that RGD-CD146+CD271+ UCMSC-Exos treatment significantly reduced the permeability of bEnd.3 cells subjected to oxygen-glucose deprivation, thereby restoring the integrity of tight junctions. Moreover, further exploration of the molecular mechanism underlying BSCB stabilization by CD146+CD271+ UCMSC-Exos identified the crucial role of the miR-501-5p/MLCK axis in this process. In conclusion, targeted delivery of RGD-CD146+CD271+ UCMSC-Exos presents a promising and effective treatment option for SCI.

Acute heart failure in elderly patients admitted to the emergency department with acute dyspnea: a multimarker approach diagnostic study.

BACKGROUND AND IMPORTANCE: Diagnosing acute heart failure (AHF) is difficult in elderly patients presenting with acute dyspnea to the emergency department. OBJECTIVES: To assess the diagnostic accuracy of NT-proBNP, high-sensitivity cardiac troponin-I (Hs-cTnI), soluble ST2 (ST2), galectin-3 and CD146 alone and in combination for diagnosing AHF in elderly patients presenting with acute dyspnea to the emergency department. DESIGN, SETTINGS AND PARTICIPANTS: This was a prospective, multicenter study performed between September 2016 and January 2020, including elderly patients presenting with acute dyspnea to the emergency department of 6 French hospitals. INTERVENTION: Measurement of NT-proBNP, hs-cTnI, ST2, galectin-3 and CD146. OUTCOME MEASURE AND ANALYSIS: The reference standard, AHF, was adjudicated by two independent physicians based on ED and hospitalization clinical, biological (excluding biomarkers), radiological and echocardiography data (performed by a cardiologist in the cardiology department specifically for this study). Three exploratory methods (two using a cross-sectional approach with logistic regression and counting all biomarker combinations, and one using a sequential approach with gray zone optimizations) were applied to create comprehensive combinations of the 5 biomarkers for measuring diagnostic accuracy. MAIN RESULTS: Two hundred thirty-eight patients (median age of 85 years, IQR = 8) were analyzed, and 110 (46%) were diagnosed with AHF. The accuracies of NT-proBNP, CD146, hs-cTnI, galectin-3, and ST2 were 0.72 [95% confidence interval (CI) 0.66-0.77], 0.63 (95% CI 0.57-0.69), 0.59 (95% CI 0.53-0.65), 0.55 (95% CI 0.49-0.61) and 0.51 (95% CI 0.45-0.57), respectively. Regardless of the approach used or how the 5 biomarkers were combined, the best accuracy for diagnosing AHF (0.73, 95% CI 0.67-0.78) did not differ from that of NT-proBNP alone. CONCLUSION: In this study, NT-proBNP alone exhibited the best diagnostic accuracy for diagnosing AHF in elderly patients presenting with acute dyspnea to the emergency departments. None of the other biomarkers alone or combined improved the accuracy compared to NT-proBNP, which is the only biomarker to use in this setting.

CD146 deficiency promotes inflammatory type 2 responses in pulmonary cryptococcosis.

Cryptococcus neoformans (C. neoformans) is an important opportunistic fungal pathogen for pulmonary cryptococcosis. Previously, we demonstrated that CD146 mediated the adhesion of C. neoformans to the airway epithelium. CD146 is more than an adhesion molecule. In the present study, we aimed to explore the roles of CD146 in the inflammatory response in pulmonary cryptococcosis. CD146 was decreased in lung tissues from patients with pulmonary cryptococcosis. Similarly, C. neoformans reduced pulmonary CD146 expression in mice following intratracheal inoculation. To explore the pathological roles of CD146 reduction in pulmonary cryptococcosis, CD146 knockout (KO) mice were inoculated with C. neoformans via intratracheal instillation. CD146 deficiency aggravated C. neoformans infection, as evidenced by a shortened survival time and increased fungal burdens in the lung. Inflammatory type 2 cytokines (IL-4, IL-5, and TNF-α) and alternatively activated macrophages were increased in the pulmonary tissues of CD146 KO-infected mice. CD146 is expressed in immune cells (macrophages, etc.) and nonimmune cells, i.e., epithelial cells and endothelial cells. Bone marrow chimeric mice were established and infected with C. neoformans. CD146 deficiency in immune cells but not in nonimmune cells increased fungal burdens in the lung. Mechanistically, upon C. neoformans challenge, CD146 KO macrophages produced more neutrophil chemokine KC and inflammatory cytokine TNF-α. Meanwhile, CD146 KO macrophages decreased the fungicidity and production of reactive oxygen species. Collectively, C. neoformans infection decreased CD146 in pulmonary tissues, leading to inflammatory type 2 responses, while CD146 deficiency worsened pulmonary cryptococcosis.

Conservation of Markers and Stemness in Adipose Stem and Progenitor Cells between Cattle and Other Species.

Adipose stem and progenitor cells (ASPCs) have been isolated from humans and animals for use in regenerative medicine and therapy. However, knowledge of ASPCs in other species is limited. Particularly, ASPCs in livestock are expected to enhance the fat content and meat composition. In this study, we isolated bovine ASPCs using cell surface markers. Specifically, we focused on ASPC markers in humans and experimental animals, namely CD26, CD146, and CD54. Stromal vascular fraction cells from bovine fat were separated using flow cytometry before primary culture. We evaluated the self-renewal and adipogenic potential of each fraction. We identified four cell populations: CD26-CD146+CD54+, CD26-CD146+CD54-, CD26-CD146-, and CD26+CD146-. Among them, the CD26-CD146+ fraction, particularly CD54+, demonstrated the properties of preadipocytes (PreAs), characterized by slow proliferation and a high adipogenic capacity. In conclusion, we could collect and characterize possible PreAs as CD26-CD146+CD54+ or CD26-CD146+CD54-, which are expected for in vitro bovine adipogenic assays in the future.

Differential pericyte marker expression in craniofacial benign and malignant vascular tumors.

BACKGROUND: Vascular anomalies and tumors are common in the head, neck, and craniofacial areas and are associated with abnormalities in the angiomatous architecture. However, the etiology and molecular basis for the pathogenesis of most vascular lesions are still unknown. Pericytes are mural cells that surround endothelial cells. Besides angiogenesis and other physiological functions, pericytes play an important role in vascularized tissue repair and as resident mesenchymal stem/progenitor cells. Perivascular cells demonstrate a distinct immunohistochemical profile, including expression of alpha-smooth muscle actin (α-SMA), CD146, CD105, and PDGFRß, without endothelial differentiation (absence of CD31 and CD34 immunoreactivity). These pericyte markers have been shown to be expressed in soft tissue hemangiomas. However, they have not been fully examined in intraosseous hemangiomas. METHODS: In this study, we compared mesenchymal stem cell (MSC) expression of CD146 and α-SMA markers in pericytes from hemangiomas from different tissues and malignant vascular tumors. RESULTS: The results demonstrated an increased expression of pericyte markers in perivascular cells of benign hemangiomas, especially intraosseous hemangiomas and a significantly reduced expression of pericyte markers in malignant angiosarcomas. CONCLUSION: The evidence provides insight into the function of pericytes in vascular tumors and suggests their role in vascular tumor disease types.

A subpopulation of CD146+ macrophages enhances antitumor immunity by activating the NLRP3 inflammasome.

As one of the main tumor-infiltrating immune cell types, tumor-associated macrophages (TAMs) determine the efficacy of immunotherapy. However, limited knowledge about their phenotypically and functionally heterogeneous nature restricts their application in tumor immunotherapy. In this study, we identified a subpopulation of CD146+ TAMs that exerted antitumor activity in both human samples and animal models. CD146 expression in TAMs was negatively controlled by STAT3 signaling. Reducing this population of TAMs promoted tumor development by facilitating myeloid-derived suppressor cell recruitment via activation of JNK signaling. Interestingly, CD146 was involved in the NLRP3 inflammasome-mediated activation of macrophages in the tumor microenvironment, partially by inhibiting transmembrane protein 176B (TMEM176B), an immunoregulatory cation channel. Treatment with a TMEM176B inhibitor enhanced the antitumor activity of CD146+ TAMs. These data reveal a crucial antitumor role of CD146+ TAMs and highlight the promising immunotherapeutic approach of inhibiting CD146 and TMEM176B.