CD146, from a melanoma cell adhesion molecule to a signaling receptor

Survival strategies: How tumor hypoxia microenvironment orchestrates angiogenesis

During tumor development, the tumor itself must continuously generate new blood vessels to meet their growth needs while also allowing for tumor invasion and metastasis. One of the most common features of tumors is hypoxia, which drives the process of tumor angiogenesis by regulating the tumor microenvironment, thus adversely affecting the prognosis of patients. In addition, to overcome unsuitable environments for growth, such as hypoxia, nutrient deficiency, hyperacidity, and immunosuppression, the tumor microenvironment (TME) coordinates angiogenesis in several ways to restore the supply of oxygen and nutrients and to remove metabolic wastes. A growing body of research suggests that tumor angiogenesis and hypoxia interact through a complex interplay of crosstalk, which is inextricably linked to the TME. Here, we review the TME's positive contribution to angiogenesis from an angiogenesis-centric perspective while considering the objective impact of hypoxic phenotypes and the status and limitations of current angiogenic therapies.

CD146-dependent macrophage infiltration promotes epidural fibrosis via the Erdr1/ERK/CCR2 pathway

Low back pain due to epidural fibrosis is a major complication after spine surgery. Macrophages infiltrate the wound area post laminectomy, but the role of macrophages in epidural fibrosis remains largely elusive. In a mouse model of laminectomy, macrophage depletion decreased epidural fibrosis. CD146, an adhesion molecule involved in cell migration, is expressed by macrophages. CD146-defective macrophages exhibited impaired migration, which was mediated by reduced expression of CCR2 and suppression of the MAPK/ERK signaling pathway. CD146-defective macrophages suppress the MAPK/ERK signaling pathway by increasing Erdr1. In vivo, CD146 deficiency decreased macrophage infiltration and reduced extracellular matrix deposition in wound tissues. Moreover, the anti-CD146 antibody AA98 suppressed macrophage infiltration and epidural fibrosis. Taken together, these findings demonstrated that CD146 deficiency alleviates epidural fibrosis by decreasing the migration of macrophages via the Erdr1/ERK/CCR2 pathway. Blocking CD146 and macrophage infiltration may help alleviate epidural fibrosis.

Exosomes multiplex profiling, a promising strategy for early diagnosis of laryngeal cancer

BACKGROUND

Exosomes are nanosized vesicles released from all cells into surrounding biofluids, including cancer cells, and represent a very promising direction in terms of minimally invasive approaches to early disease detection. They carry tumor-specific biological contents such as DNA, RNA, proteins, lipids, and sugars, as well as surface molecules that are able to pinpoint the cellular source. By the above criteria, exosomes may be stratified according to the presence of tissue and disease-specific signatures and, due to their stability in such biofluids as plasma and serum, they represent an indispensable source of vital clinical insights from liquid biopsies, even at the earliest stages of cancer. Therefore, our work aimed to isolate and characterize LCa patients' derived exosomes from serum by Flow Cytometry in order to define a specific epitope signature exploitable for early diagnosis.

METHODS

Circulating exosomes were collected from serum collected from 30 LCa patients and 20 healthy volunteers by the use of antibody affinity method exploiting CD63 specific surface marker. Membrane epitopes were then characterized by Flow cytometry multiplex analysis and compared between LCa Patients and Healthy donors. Clinical data were also matched to obtain statistical correlation.

RESULTS

A distinct overexpression of CD1c, CD2, CD3, CD4, CD11c, CD14, CD20, CD44, CD56, CD105, CD146, and CD209 was identified in LCa patients compared to healthy controls, correlating positively with tumor presence. Conversely, CD24, CD31, and CD40, though not overexpressed in tumor samples, showed a significant correlation with nodal involvement in LCa patients (p < 0.01).

CONCLUSION

This approach could allow us to set up a cost-effective and less invasive liquid biopsy protocol from a simple blood collection in order to early diagnose LCa and improve patients' outcomes and quality of life.

LAYN Serves as a Prognostic Biomarker and Downregulates Tumor-Infiltrating CD8+ T Cell Function in Hepatocellular Carcinoma

Background

Layilin (LAYN) represents a valuable prognostic biomarker across various tumor types, while also serving as an innovative indicator of dysfunctional or exhausted CD8+ T cells and exhibiting correlation with immune context. However, the immune function and prognostic significance of LAYN in hepatocellular carcinoma (HCC) remain unexplored. Therefore, our objective is to investigate the role of LAYN in CD8+ T cell exhaustion, clinical prognosis, and the tumor microenvironment within HCC.

Methods

TIMER or GEPIA databases were used to analyze LAYN expression level and its correlation with immune infiltration in HCC. Bioinformatics analysis was conducted on TCGA and scRNA-seq cohorts. The evaluation of LAYN expression level in fresh specimens was performed through IF, IHC, and ELISA assays. Flow cytometry and mRNA-seq were employed to investigate co-expressed genes of LAYN, the LAYN+CD8+ T cell exhaustion signature and immune function. Cell proliferation ability and killing activity were assessed using CCK8 and CFSE/PI.

Results

The expression level of LAYN in HCC tumors was significantly higher compared to peri-tumors. Patients with high levels of LAYN exhibited poorer OS. GO or KEGG analysis confirmed that LAYN was involved in immune response and was positively associated with CD8+ T cell immune infiltration levels. Furthermore, LAYN negatively regulated the immune function of CD8+ T cells, leading to dysfunctional phenotypes characterized by elevated levels of CD39, TIM3 and reduced levels of perforin, TNF-α, Ki-67. CFSE/PI assays demonstrated that LAYN+CD8+ T cells displayed decreased cytotoxic activity. Additionally, there was a positive correlation between LAYN and CD146 levels, which are involved in adhesion and localization processes of CD8+ T cells. Interestingly, blocking LAYN partially restored the exhaustion properties of CD8+ T cells.

Conclusion

LAYN exhibits a strong correlation with immune infiltration in the TME and represents a novel biomarker for predicting clinical prognosis in HCC. Moreover, targeting LAYN may hold promise as an effective strategy for HCC immunotherapy.

Unveiling heterogeneity in MSCs: exploring marker-based strategies for defining MSC subpopulations

Mesenchymal stem/stromal cells (MSCs) represent a heterogeneous cell population distributed throughout various tissues, demonstrating remarkable adaptability to microenvironmental cues and holding immense promise for disease treatment. However, the inherent diversity within MSCs often leads to variability in therapeutic outcomes, posing challenges for clinical applications. To address this heterogeneity, purification of MSC subpopulations through marker-based isolation has emerged as a promising approach to ensure consistent therapeutic efficacy. In this review, we discussed the reported markers of MSCs, encompassing those developed through candidate marker strategies and high-throughput approaches, with the aim of explore viable strategies for addressing the heterogeneity of MSCs and illuminate prospective research directions in this field.

The Congestion "Pandemic" in Acute Heart Failure Patients

Congestion not only represents a cardinal sign of heart failure (HF) but is also now recognized as the primary cause of hospital admissions, rehospitalization, and mortality among patients with acute heart failure (AHF). Congestion can manifest through various HF phenotypes in acute settings: volume overload, volume redistribution, or both. Recognizing the congestion phenotype is paramount, as it implies different therapeutic strategies for decongestion. Among patients with AHF, achieving complete decongestion is challenging, as more than half still experience residual congestion at discharge. Residual congestion is one of the strongest predictors of future cardiovascular events and poor outcomes. Through this review, we try to provide a better understanding of the congestion phenomenon among patients with AHF by highlighting insights into the pathophysiological mechanisms behind congestion and new diagnostic and management tools to achieve and maintain efficient decongestion.

CD146, a therapeutic target involved in cell plasticity

Since its identification as a marker for advanced melanoma in the 1980s, CD146 has been found to have multiple functions in both physiological and pathological processes, including embryonic development, tissue repair and regeneration, tumor progression, fibrosis disease, and inflammations. Subsequent research has revealed that CD146 is involved in various signaling pathways as a receptor or co-receptor in these processes. This correlation between CD146 and multiple diseases has sparked interest in its potential applications in diagnosis, prognosis, and targeted therapy. To better comprehend the versatile roles of CD146, we have summarized its research history and synthesized findings from numerous reports, proposing that cell plasticity serves as the underlying mechanism through which CD146 contributes to development, regeneration, and various diseases. Targeting CD146 would consequently halt cell state shifting during the onset and progression of these related diseases. Therefore, the development of therapy targeting CD146 holds significant practical value.

The fate and role of the pericytes in myocardial diseases

The adult mammalian heart contains a large population of pericytes that play important roles in homeostasis and disease. In the normal heart, pericytes regulate microvascular permeability and flow. Myocardial diseases are associated with marked alterations in pericyte phenotype and function. This review manuscript discusses the role of pericytes in cardiac homeostasis and disease. Following myocardial infarction (MI), cardiac pericytes participate in all phases of cardiac repair. During the inflammatory phase, pericytes may secrete cytokines and chemokines and may regulate leukocyte trafficking, through formation of intercellular gaps that serve as exit points for inflammatory cells. Moreover, pericyte contraction induces microvascular constriction, contributing to the pathogenesis of 'no-reflow' in ischemia and reperfusion. During the proliferative phase, pericytes are activated by growth factors, such as transforming growth factor (TGF)-β and contribute to fibrosis, predominantly through secretion of fibrogenic mediators. A fraction of pericytes acquires fibroblast identity but contributes only to a small percentage of infarct fibroblasts and myofibroblasts. As the scar matures, pericytes form a coat around infarct neovessels, promoting stabilization of the vasculature. Pericytes may also be involved in the pathogenesis of chronic heart failure, by regulating inflammation, fibrosis, angiogenesis and myocardial perfusion. Pericytes are also important targets of viral infections (such as SARS-CoV2) and may be implicated in the pathogenesis of cardiac complications of COVID19. Considering their role in myocardial inflammation, fibrosis and angiogenesis, pericytes may be promising therapeutic targets in myocardial disease.

Mcam stabilizes luminal progenitor breast cancer phenotypes via Ck2 control and Src/Akt/Stat3 attenuation

Breast cancers are categorized into subtypes with distinctive therapeutic vulnerabilities and prognoses based on their expression of clinically targetable receptors and gene expression patterns mimicking different cell types of the normal gland. Here, we tested the role of Mcam in breast cancer cell state control and tumorigenicity in a luminal progenitor-like murine tumor cell line (Py230) that exhibits lineage and tumor subtype plasticity. Mcam knockdown Py230 cells show augmented Stat3 and Pi3K/Akt activation associated with a lineage state switch away from a hormone-sensing/luminal progenitor state toward alveolar and basal cell related phenotypes that were refractory to growth inhibition by the anti-estrogen therapeutic, tamoxifen. Inhibition of Stat3, or the upstream activator Ck2, reversed these cell state changes. Mcam binds Ck2 and acts as a regulator of Ck2 substrate utilization across multiple mammary tumor cell lines. In Py230 cells this activity manifests as increased mesenchymal morphology, migration, and Src/Fak/Mapk/Paxillin adhesion complex signaling in vitro, in contrast to Mcam's reported roles in promoting mesenchymal phenotypes. In vivo, Mcam knockdown reduced tumor growth and take rate and inhibited cell state transition to Sox10+/neural crest like cells previously been associated with tumor aggressiveness. This contrasts with human luminal breast cancers where MCAM copy number loss is highly coupled to Cyclin D amplification, increased proliferation, and the more aggressive Luminal B subtype. Together these data indicate a critical role for Mcam and its regulation of Ck2 in control of breast cancer cell state plasticity with implications for progression, evasion of targeted therapies and combination therapy design.

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.

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.

Immunological Profile and Markers of Endothelial Dysfunction in Elderly Patients with Cognitive Impairments

The process of aging is accompanied by a dynamic restructuring of the immune response, a phenomenon known as immunosenescence. Further, damage to the endothelium can be both a cause and a consequence of many diseases, especially in elderly people. The purpose of this study was to carry out immunological and biochemical profiling of elderly people with acute ischemic stroke (AIS), chronic cerebral circulation insufficiency (CCCI), prediabetes or newly diagnosed type II diabetes mellitus (DM), and subcortical ischemic vascular dementia (SIVD). Socio-demographic, lifestyle, and cognitive data were obtained. Biochemical, hematological, and immunological analyses were carried out, and extracellular vesicles (EVs) with endothelial CD markers were assessed. The greatest number of significant deviations from conditionally healthy donors (HDs) of the same age were registered in the SIVD group, a total of 20, of which 12 were specific and six were non-specific but with maximal differences (as compared to the other three groups) from the HDs group. The non-specific deviations were for the MOCA (Montreal Cognitive Impairment Scale), the MMSE (Mini Mental State Examination) and life satisfaction self-assessment scores, a decrease of albumin levels, and ADAMTS13 (a Disintegrin and Metalloproteinase with a Thrombospondin Type 1 motif, member 13) activity, and an increase of the VWF (von Willebrand factor) level. Considering the significant changes in immunological parameters (mostly Th17-like cells) and endothelial CD markers (CD144 and CD34), vascular repair was impaired to the greatest extent in the DM group. The AIS patients showed 12 significant deviations from the HD controls, including three specific to this group. These were high NEFAs (non-esterified fatty acids) and CD31 and CD147 markers of EVs. The lowest number of deviations were registered in the CCCI group, nine in total. There were significant changes from the HD controls with no specifics to this group, and just one non-specific with a maximal difference from the control parameters, which was α1-AGP (alpha 1 acid glycoprotein, orosomucoid). Besides the DM patients, impairments of vascular repair were also registered in the CCCI and AIS patients, with a complete absence of such in patients with dementia (SIVD group). On the other hand, microvascular damage seemed to be maximal in the latter group, considering the biochemical indicators VWF and ADAMTS13. In the DM patients, a maximum immune response was registered, mainly with Th17-like cells. In the CCCI group, the reaction was not as pronounced compared to other groups of patients, which may indicate the initial stages and/or compensatory nature of organic changes (remodeling). At the same time, immunological and biochemical deviations in SIVD patients indicated a persistent remodeling in microvessels, chronic inflammation, and a significant decrease in the anabolic function of the liver and other tissues. The data obtained support two interrelated assumptions. Taking into account the primary biochemical factors that trigger the pathological processes associated with vascular pathology and related diseases, the first assumption is that purine degradation in skeletal muscle may be a major factor in the production of uric acid, followed by its production by non-muscle cells, the main of which are endothelial cells. Another assumption is that therapeutic factors that increase the levels of endothelial progenitor cells may have a therapeutic effect in reducing the risk of cerebrovascular disease and related neurodegenerative diseases.

Expression of placental CD146 is dysregulated by prenatal alcohol exposure and contributes in cortical vasculature development and positioning of vessel-associated oligodendrocytes

Recent data showed that prenatal alcohol exposure (PAE) impairs the "placenta-brain" axis controlling fetal brain angiogenesis in human and preclinical models. Placental growth factor (PlGF) has been identified as a proangiogenic messenger between these two organs. CD146, a partner of the VEGFR-1/2 signalosome, is involved in placental angiogenesis and exists as a soluble circulating form. The aim of the present study was to investigate whether placental CD146 may contribute to brain vascular defects described in fetal alcohol spectrum disorder. At a physiological level, quantitative reverse transcription polymerase chain reaction experiments performed in human placenta showed that CD146 is expressed in developing villi and that membrane and soluble forms of CD146 are differentially expressed from the first trimester to term. In the mouse placenta, a similar expression pattern of CD146 was found. CD146 immunoreactivity was detected in the labyrinth zone and colocalized with CD31-positive endothelial cells. Significant amounts of soluble CD146 were quantified by ELISA in fetal blood, and the levels decreased after birth. In the fetal brain, the membrane form of CD146 was the majority and colocalized with microvessels. At a pathophysiological level, PAE induced marked dysregulation of CD146 expression. The soluble form of CD146 decreased in both placenta and fetal blood, whereas it increased in the fetal brain. Similarly, the expression of several members of the CD146 signalosome, such as VEGFR2 and PSEN, was differentially impaired between the two organs by PAE. At a functional level, targeted repression of placental CD146 by in utero electroporation (IUE) of CRISPR/Cas9 lentiviral plasmids resulted in (i) a decrease in cortical vessel density, (ii) a loss of radial vascular organization, and (iii) a reduced density of oligodendrocytes. Statistical analysis showed that the more the vasculature was impaired, the more the cortical oligodendrocyte density was reduced. Altogether, these data support that placental CD146 contributes to the proangiogenic "placenta-brain" axis and that placental CD146 dysfunction contributes to the cortical oligo-vascular development. Soluble CD146 would represent a promising placental biomarker candidate representative of alcohol-induced neurovascular defects in neonates, as recently suggested by PlGF (patents WO2016207253 and WO2018100143).

Mcam inhibits macrophage-mediated development of mammary gland through non-canonical Wnt signaling

While canonical Wnt signaling is well recognized for its crucial regulatory functions in cell fate decisions, the role of non-canonical Wnt signaling in adult stem cells remains elusive and contradictory. Here, we identified Mcam, a potential member of the non-canonical Wnt signaling, as an important negative regulator of mammary gland epithelial cells (MECs) by genome-scale CRISPR-Cas9 knockout (GeCKO) library screening. Loss of Mcam increases the clonogenicity and regenerative capacity of MECs, and promotes the proliferation, differentiation, and ductal morphogenesis of mammary epithelial in knockout mice. Mechanically, Mcam knockout recruits and polarizes macrophages through the Il4-Stat6 axis, thereby promoting secretion of the non-canonical Wnt ligand Wnt5a and its binding to the non-canonical Wnt signaling receptor Ryk to induce the above phenotypes. These findings reveal Mcam roles in mammary gland development by orchestrating communications between MECs and macrophages via a Wnt5a/Ryk axis, providing evidences for non-canonical Wnt signaling in mammary development.

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.

CD49f and CD146: A Possible Crosstalk Modulates Adipogenic Differentiation Potential of Mesenchymal Stem Cells

BACKGROUND

The lack of appropriate mesenchymal stem cells (MSCs) selection methods has given the challenges for standardized harvesting, processing, and phenotyping procedures of MSCs. Genetic engineering coupled with high-throughput proteomic studies of MSC surface markers arises as a promising strategy to identify stem cell-specific markers. However, the technical limitations are the key factors making it less suitable to provide an appropriate starting material for the screening platform. A more accurate, easily accessible approach is required to solve the issues.

METHODS

This study established a high-throughput screening strategy with forward versus side scatter gating to identify the adipogenesis-associated markers of bone marrow-derived MSCs (BMSCs) and tonsil-derived MSCs (TMSCs). We classified the MSC-derived adipogenic differentiated cells into two clusters: lipid-rich cells as side scatter (SSC)-high population and lipid-poor cells as SSC-low population. By screening the expression of 242 cell surface proteins, we identified the surface markers which exclusively found in lipid-rich subpopulation as the specific markers for BMSCs and TMSCs.

RESULTS

High-throughput screening of the expression of 242 cell surface proteins indicated that CD49f and CD146 were specific for BMSCs and TMSCs. Subsequent immunostaining confirmed the consistent specific expression of CD49f and CD146 and in BMSCs and TMSCs. Enrichment of MSCs by CD49f and CD146 surface markers demonstrated that the simultaneous expression of CD49f and CD146 is required for adipogenesis and osteogenesis of mesenchymal stem cells. Furthermore, the fate decision of MSCs from different sources is regulated by distinct responses of cells to differentiation stimulations despite sharing a common CD49f+CD146+ immunophenotype.

CONCLUSIONS

We established an accurate, robust, transgene-free method for screening adipogenesis associated cell surface proteins. This provided a valuable tool to investigate MSC-specific markers. Additionally, we showed a possible crosstalk between CD49f and CD146 modulates the adipogenesis of MSCs.

The universe of galectin-binding partners and their functions in health and disease

Galectins, a family of evolutionarily conserved glycan-binding proteins, play key roles in diverse biological processes including tissue repair, adipogenesis, immune cell homeostasis, angiogenesis, and pathogen recognition. Dysregulation of galectins and their ligands has been observed in a wide range of pathologic conditions including cancer, autoimmune inflammation, infection, fibrosis, and metabolic disorders. Through protein-glycan or protein-protein interactions, these endogenous lectins can shape the initiation, perpetuation, and resolution of these processes, suggesting their potential roles in disease monitoring and treatment. However, despite considerable progress, a full understanding of the biology and therapeutic potential of galectins has not been reached due to their diversity, multiplicity of cell targets, and receptor promiscuity. In this article, we discuss the multiple galectin-binding partners present in different cell types, focusing on their contributions to selected physiologic and pathologic settings. Understanding the molecular bases of galectin-ligand interactions, particularly their glycan-dependency, the biochemical nature of selected receptors, and underlying signaling events, might contribute to designing rational therapeutic strategies to control a broad range of pathologic conditions.

Optimal temperature for the long-term culture of adult porcine islets for xenotransplantation

Porcine islet xenotransplantation represents a promising therapy for severe diabetes mellitus. Long-term culture of porcine islets is a crucial challenge to permit the on-demand provision of islets. We aimed to identify the optimal temperature for the long-term culture of adult porcine islets for xenotransplantation. We evaluated the factors potentially influencing successful 28-day culture of islets at 24°C and 37°C, and found that culture at 37°C contributed to the stability of the morphology of the islets, the proliferation of islet cells, and the recovery of endocrine function, indicated by the expression of genes involved in pancreatic development, hormone production, and glucose-stimulated insulin secretion. These advantages may be provided by islet-derived CD146-positive stellate cells. The efficacy of xenotransplantation using islets cultured for a long time at 37°C was similar to that of overnight-cultured islets. In conclusion, 37°C might be a suitable temperature for the long-term culture of porcine islets, but further modifications will be required for successful xenotransplantation in a clinical setting.

Identification of potential molecular targets for the treatment of cluster 1 human pheochromocytoma and paraganglioma via comprehensive proteomic characterization

BACKGROUND

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors. New drug targets and proteins that would assist sensitive PPGL imagining could improve therapy and quality of life of patients with PPGL, namely those with recurrent or metastatic disease. Using a combined proteomic strategy, we looked for such clinically relevant targets among integral membrane proteins (IMPs) upregulated on the surface of tumor cells and non-membrane druggable enzymes in PPGL.

METHODS

We conducted a detailed proteomic analysis of 22 well-characterized human PPGL samples and normal chromaffin tissue from adrenal medulla. A standard quantitative proteomic analysis of tumor lysate, which provides information largely on non-membrane proteins, was accompanied by specific membrane proteome-aimed methods, namely glycopeptide enrichment using lectin-affinity, glycopeptide capture by hydrazide chemistry, and enrichment of membrane-embedded hydrophobic transmembrane segments.

RESULTS

The study identified 67 cell surface integral membrane proteins strongly upregulated in PPGL compared to control chromaffin tissue. We prioritized the proteins based on their already documented direct role in cancer cell growth or progression. Increased expression of the seven most promising drug targets (CD146, CD171, ANO1, CD39, ATP8A1, ACE and SLC7A1) were confirmed using specific antibodies. Our experimental strategy also provided expression data for soluble proteins. Among the druggable non-membrane enzymes upregulated in PPGL, we identified three potential drug targets (SHMT2, ARG2 and autotaxin) and verified their upregulated expression.

CONCLUSIONS

Application of a combined proteomic strategy recently presented as "Pitchfork" enabled quantitative analysis of both, membrane and non-membrane proteome, and resulted in identification of 10 potential drug targets in human PPGL. Seven membrane proteins localized on the cell surface and three non-membrane druggable enzymes proteins were identified and verified as significantly upregulated in PPGL. All the proteins have been previously shown to be upregulated in several human cancers, and play direct role in cancer progression. Marked upregulation of these proteins along with their localization and established direct roles in tumor progression make these molecules promising candidates as drug targets or proteins for sensitive PPGL imaging.

Hypoxia and panvascular diseases: exploring the role of hypoxia-inducible factors in vascular smooth muscle cells under panvascular pathologies

As an emerging discipline, panvascular diseases are a set of vascular diseases with atherosclerosis as the common pathogenic hallmark, which mostly affect vital organs like the heart, brain, kidney, and limbs. As the major responser to the most common stressor in the vasculature (hypoxia)-hypoxia-inducible factors (HIFs), and the primary regulator of pressure and oxygen delivery in the vasculature-vascular smooth muscle cells (VSMCs), their own multifaceted nature and their interactions with each other are fascinating. Abnormally active VSMCs (e.g., atherosclerosis, pulmonary hypertension) or abnormally dysfunctional VSMCs (e.g., aneurysms, vascular calcification) are associated with HIFs. These widespread systemic diseases also reflect the interdisciplinary nature of panvascular medicine. Moreover, given the comparable proliferative characteristics exhibited by VSMCs and cancer cells, and the delicate equilibrium between angiogenesis and cancer progression, there is a pressing need for more accurate modulation targets or combination approaches to bolster the effectiveness of HIF targeting therapies. Based on the aforementioned content, this review primarily focused on the significance of integrating the overall and local perspectives, as well as temporal and spatial balance, in the context of the HIF signaling pathway in VSMC-related panvascular diseases. Furthermore, the review discussed the implications of HIF-targeting drugs on panvascular disorders, while considering the trade-offs involved.

Immunomodulatory properties of the lymphatic endothelium in the tumor microenvironment

The tumor microenvironment (TME) is an intricate complex and dynamic structure composed of various cell types, including tumor, stromal and immune cells. Within this complex network, lymphatic endothelial cells (LECs) play a crucial role in regulating immune responses and influencing tumor progression and metastatic dissemination to lymph node and distant organs. Interestingly, LECs possess unique immunomodulatory properties that can either promote or inhibit anti-tumor immune responses. In fact, tumor-associated lymphangiogenesis can facilitate tumor cell dissemination and metastasis supporting immunoevasion, but also, different molecular mechanisms involved in LEC-mediated anti-tumor immunity have been already described. In this context, the crosstalk between cancer cells, LECs and immune cells and how this communication can shape the immune landscape in the TME is gaining increased interest in recent years. In this review, we present a comprehensive and updated report about the immunomodulatory properties of the lymphatic endothelium within the TME, with special focus on primary tumors and tumor-draining lymph nodes. Furthermore, we outline emerging research investigating the potential therapeutic strategies targeting the lymphatic endothelium to enhance anti-tumor immune responses. Understanding the intricate mechanisms involved in LEC-mediated immune modulation in the TME opens up new possibilities for the development of innovative approaches to fight cancer.

The functions and regulatory pathways of S100A8/A9 and its receptors in cancers

Inflammation primarily influences the initiation, progression, and deterioration of many human diseases, and immune cells are the principal forces that modulate the balance of inflammation by generating cytokines and chemokines to maintain physiological homeostasis or accelerate disease development. S100A8/A9, a heterodimer protein mainly generated by neutrophils, triggers many signal transduction pathways to mediate microtubule constitution and pathogen defense, as well as intricate procedures of cancer growth, metastasis, drug resistance, and prognosis. Its paired receptors, such as receptor for advanced glycation ends (RAGEs) and toll-like receptor 4 (TLR4), also have roles and effects within tumor cells, mainly involved with mitogen-activated protein kinases (MAPKs), NF-κB, phosphoinositide 3-kinase (PI3K)/Akt, mammalian target of rapamycin (mTOR) and protein kinase C (PKC) activation. In the clinical setting, S100A8/A9 and its receptors can be used complementarily as efficient biomarkers for cancer diagnosis and treatment. This review comprehensively summarizes the biological functions of S100A8/A9 and its various receptors in tumor cells, in order to provide new insights and strategies targeting S100A8/A9 to promote novel diagnostic and therapeutic methods in cancers.

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.

Bifidobacterium infantis-Mediated Herpes Simplex Virus-TK/Ganciclovir Treatment Inhibits Cancer Metastasis in Mouse Model

Previous studies have found that Bifidobacterium infantis-mediated herpes simplex virus-TK/ganciclovir (BF-TK/GCV) reduces the expression of VEGF and CD146, implying tumor metastasis inhibition. However, the mechanism by which BF-TK/GCV inhibits tumor metastasis is not fully studied. Here, we comprehensively identified and quantified protein expression profiling for the first time in gastric cancer (GC) cells MKN-45 upon BF-TK/GCV treatment using quantitative proteomics. A total of 159 and 72 differential expression proteins (DEPs) were significantly changed in the BF-TK/GCV/BF-TK and BF-TK/GCV/BF/GCV comparative analysis. Kyoto encyclopedia of genes and genomes (KEGG) pathway analysis enriched some metastasis-related pathways such as gap junction and cell adhesion molecules pathways. Moreover, the transwell assay proved that BF-TK/GCV inhibited the invasion and migration of tumor cells. Furthermore, immunohistochemistry (IHC) demonstrated that BF-TK/GCV reduced the expression of HIF-1α, mTOR, NF-κB1-p105, VCAM1, MMP13, CXCL12, ATG16, and CEBPB, which were associated with tumor metastasis. In summary, BF-TK/GCV inhibited tumor metastasis, which deepened and expanded the understanding of the antitumor mechanism of BF-TK/GCV.

MCAM+CD161- Th17 Subset Expressing CD83 Enhances Tc17 Response in Psoriasis

Recent studies have highlighted the pathogenic roles of IL-17-producing CD8+ T cells (T-cytotoxic 17 [Tc17]) in psoriasis. However, the underlying mechanisms of Tc17 induction remain unclear. In this study, we focused on the pathogenic subsets of Th17 and their mechanism of promotion of Tc17 responses. We determined that the pathogenic Th17-enriched fraction expressed melanoma cell adhesion molecule (MCAM) and CCR6, but not CD161, because this subset produced IL-17A abundantly and the presence of these cells in the peripheral blood of patients has been correlated with the severity of psoriasis. Intriguingly, the serial analysis of gene expression revealed that CCR6+MCAM+CD161-CD4+ T cells displayed the gene profile for adaptive immune responses, including CD83, which is an activator for CD8+ T cells. Coculture assay with or without intercellular contact between CD4+ and CD8+ T cells showed that CCR6+MCAM+CD161-CD4+ T cells induced the proliferation of CD8+ T cells in a CD83-dependent manner. However, the production of IL-17A by CD8+ T cells required exogenous IL-17A, suggesting that intercellular contact via CD83 and the production of IL-17A from activated CD4+ T cells elicit Tc17 responses. Intriguingly, the CD83 expression was enhanced in the presence of IL-15, and CD83+ cells stimulated with IL-1β, IL-23, IL-15, and IL-15Rα did not express FOXP3. Furthermore, CCR6+MCAM+CD161-CD4+ T cells expressing CD83 were increased in the peripheral blood of patients, and the CD83+ Th17-type cells accumulated in the lesional skin of psoriasis. In conclusion, pathogenic MCAM+CD161- Th17 cells may be involved in the Tc17 responses via IL-17A and CD83 in psoriasis.

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.

MCAM+ brain endothelial cells contribute to neuroinflammation by recruiting pathogenic CD4+ T lymphocytes

The trafficking of autoreactive leucocytes across the blood-brain barrier endothelium is a hallmark of multiple sclerosis pathogenesis. Although the blood-brain barrier endothelium represents one of the main CNS borders to interact with the infiltrating leucocytes, its exact contribution to neuroinflammation remains understudied. Here, we show that Mcam identifies inflammatory brain endothelial cells with pro-migratory transcriptomic signature during experimental autoimmune encephalomyelitis. In addition, MCAM was preferentially upregulated on blood-brain barrier endothelial cells in multiple sclerosis lesions in situ and at experimental autoimmune encephalomyelitis disease onset by molecular MRI. In vitro and in vivo, we demonstrate that MCAM on blood-brain barrier endothelial cells contributes to experimental autoimmune encephalomyelitis development by promoting the cellular trafficking of TH1 and TH17 lymphocytes across the blood-brain barrier. Last, we showcase ST14 as an immune ligand to brain endothelial MCAM, enriched on CD4+ T lymphocytes that cross the blood-brain barrier in vitro, in vivo and in multiple sclerosis lesions as detected by flow cytometry on rapid autopsy derived brain tissue from multiple sclerosis patients. Collectively, our findings reveal that MCAM is at the centre of a pathological pathway used by brain endothelial cells to recruit pathogenic CD4+ T lymphocyte from circulation early during neuroinflammation. The therapeutic targeting of this mechanism is a promising avenue to treat multiple sclerosis.

Histone variant H3.3 promotes metastasis in alveolar rhabdomyosarcoma

The relatively quiet mutational landscape of rhabdomyosarcoma (RMS) suggests that epigenetic deregulation could be central to oncogenesis and tumour aggressiveness. Histone variants have long been recognised as important epigenetic regulators of gene expression. However, the role of histone variants in RMS has not been studied hitherto. In this study, we show that histone variant H3.3 is overexpressed in alveolar RMS (ARMS), an aggressive subtype of RMS. Functionally, knockdown of H3F3A, which encodes for H3.3, significantly impairs the ability of ARMS cells to undertake migration and invasion and reduces Rho activation. In addition, a striking reduction in metastatic tumour burden and improved survival is apparent in vivo. Using RNA-sequencing and ChIP-sequencing analyses, we identified melanoma cell adhesion molecule (MCAM/CD146) as a direct downstream target of H3.3. Loss of H3.3 resulted in a reduction in the presence of active marks and an increase in the occupancy of H1 at the MCAM promoter. Cell migration and invasion were rescued in H3F3A-depleted cells through MCAM overexpression. Moreover, we identified G9a, a lysine methyltransferase encoded by EHMT2, as an upstream regulator of H3F3A. Therefore, this study identifies a novel H3.3 dependent axis involved in ARMS metastasis. These findings establish the potential of MCAM as a therapeutic target for high-risk ARMS patients. © 2022 The Pathological Society of Great Britain and Ireland.

Bone Differentiation Ability of CD146-Positive Stem Cells from Human Exfoliated Deciduous Teeth

Regenerative therapy for tissues by mesenchymal stem cell (MSCs) transplantation has received much attention. The cluster of differentiation (CD)146 marker, a surface-antigen of stem cells, is crucial for angiogenic and osseous differentiation abilities. Bone regeneration is accelerated by the transplantation of CD146-positive deciduous dental pulp-derived mesenchymal stem cells contained in stem cells from human exfoliated deciduous teeth (SHED) into a living donor. However, the role of CD146 in SHED remains unclear. This study aimed to compare the effects of CD146 on cell proliferative and substrate metabolic abilities in a population of SHED. SHED was isolated from deciduous teeth, and flow cytometry was used to analyze the expression of MSCs markers. Cell sorting was performed to recover the CD146-positive cell population (CD146+) and CD146-negative cell population (CD146-). CD146 + SHED without cell sorting and CD146-SHED were examined and compared among three groups. To investigate the effect of CD146 on cell proliferation ability, an analysis of cell proliferation ability was performed using BrdU assay and MTS assay. The bone differentiation ability was evaluated using an alkaline phosphatase (ALP) stain after inducing bone differentiation, and the quality of ALP protein expressed was examined. We also performed Alizarin red staining and evaluated the calcified deposits. The gene expression of ALP, bone morphogenetic protein-2 (BMP-2), and osteocalcin (OCN) was analyzed using a real-time polymerase chain reaction. There was no significant difference in cell proliferation among the three groups. The expression of ALP stain, Alizarin red stain, ALP, BMP-2, and OCN was the highest in the CD146+ group. CD146 + SHED had higher osteogenic differentiation potential compared with SHED and CD146-SHED. CD146 contained in SHED may be a valuable population of cells for bone regeneration therapy.

Intestinal epithelium-specific Fut2 deficiency promotes colorectal cancer through down-regulating fucosylation of MCAM

BACKGROUND

Our previous study showed that fucosyltransferase 2 (Fut2) deficiency is closely related to colitis. Colitis increases the risk for the development of colorectal cancer (CRC). This study aimed to investigate the effect and underlying mechanism of action of Fut2 in CRC.

METHODS

Intestinal epithelium-specific Fut2 knockout (Fut2^△IEC) mice were used in this study. CRC was induced using azoxymethane (AOM) and dextran sulfate sodium (DSS). Immunofluorescence was used to examine the fucosylation levels. Proteomics and N-glycoproteomics analyses, Ulex Europaeus Agglutinin I (UEA-I) affinity chromatography, immunoprecipitation, and rescue assay were used to investigate the mechanism of Fut2 in CRC.

RESULTS

The expression of Fut2 and α-1,2-fucosylation was lower in colorectal tumor tissues than in the adjacent normal tissues of AOM/DSS-induced CRC mice. More colorectal tumors were detected in Fut2^△IEC mice than in control mice, and significant downregulation of melanoma cell adhesion molecule (MCAM) fucosylation was detected in the colorectal tumor tissues of Fut2^△IEC mice. Overexpression of Fut2 inhibited cell proliferation, invasion and tumor metastasis in vivo and in vitro in SW480 and HCT116 cells. Moreover, fucosylation of MCAM may be a mediator of Fut2 in CRC. Peracetylated 2-F-Fuc, a fucosyltransferase inhibitor, repressed fucosylation modification of MCAM and reversed the inhibitory effects of Fut2 overexpression on SW480 cell proliferation, migration, and invasion. Our results indicate that Fut2 deficiency in the intestinal epithelium promotes CRC by downregulating the fucosylation of MCAM.

CONCLUSIONS

The regulation of fucosylation may be an potential therapy for CRC, especially in patients with Fut2 gene defects.

ST6GAL1 inhibits metastasis of hepatocellular carcinoma via modulating sialylation of MCAM on cell surface

The poor prognosis of hepatocellular carcinoma (HCC) is mainly because of its high rate of metastasis. Thus, elucidation of the molecular mechanisms underlying HCC metastasis is of great significance. Glycosylation is an important post-translational modification that is closely associated with tumor progression. Altered glycosylation including the altered sialylation resulting from aberrant expression of β-galactoside α2,6 sialyltransferase 1 (ST6GAL1) has long been considered as an important feature of cancer cells. However, there is limited information on the roles of ST6GAL1 and α2,6 sialylation in HCC metastasis. Here, we found that ST6GAL1 and α2,6 sialylation were negatively correlated with the metastatic potentials of HCC cells. Moreover, ST6GAL1 overexpression inhibited migration and invasion of HCC cells in vitro and suppressed HCC metastasis in vivo. Using a metabolic labeling-based glycoproteomic strategy, we identified a list of sialylated proteins that may be regulated by ST6GAL1. In particular, an increase in α2,6 sialylation of melanoma cell adhesion molecule (MCAM) inhibited its interaction with galectin-3 and decreased its expression on cell surface. In vitro and in vivo analysis showed that ST6GAL1 exerted its function in HCC metastasis by regulating MCAM expression. Finally, we found the relative intensity of sialylated MCAM was negatively correlated with tumor malignancy in HCC patients. Taken together, these results demonstrate that ST6GAL1 may be an HCC metastasis suppressor by affecting sialylation of MCAM on cell surface, which provides a novel insight into the roles of ST6GAL1 in HCC progression and supports the functional complexity of ST6GAL1 in a cancer type- and tissue type-specific manner.

CD146 expression profile in human skin and pre-vascularized dermo-epidermal skin substitutes in vivo

BACKGROUND

CD146 is a cell adhesion molecule whose expression profile in human skin has not yet been elucidated. Here, we characterize CD146 expression pattern in human skin, in particular in blood endothelial cells (BECs) and lymphatic endothelial cells (LECs), which constitute human dermal microvascular endothelial cells (HDMECs), as well as in perivascular cells.

RESULTS

We demonstrated that CD146 is a specific marker of BECs, but not of LECs. Moreover, we found CD146 expression also in human pericytes surrounding blood capillaries in human skin. In addition, we demonstrated that CD146 expression is up-regulated by the TNFα-IL-1β/NF-kB axis in both BECs and pericytes. Finally, we engineered 3D collagen hydrogels composed of HDMECs, CD146⁺ pericytes, and fibroblasts which developed, in vitro and in vivo, a complete microvasculature network composed of blood and lymphatic capillaries with pericytes investing blood capillaries.

CONCLUSIONS

Overall, our results proved that CD146 is a specific marker of BECs and pericytes, but not LECs in human skin. Further, the combination of CD146⁺ pericytes with HDMECs in skin substitutes allowed to bioengineer a comprehensive 3D in vitro and in vivo model of the human dermal microvasculature.

Neurological manifestations of SARS-CoV-2 infections: towards quantum dots based management approaches

Developing numerous nanotechnological designed tools to monitor the existence of SARS-CoV-2, and modifying its interactions address the global needs for efficient remedies required for the management of COVID-19. Herein, through a multidisciplinary outlook encompassing different fields such as the pathophysiology of SARS-CoV-2, analysis of symptoms, and statistics of neurological complications caused by SARS-CoV-2 infection in the central and peripheral nervous systems have been testified. The anosmia (51.1%) and ageusia (45.5%) are reported the most frequent neurological manifestation. Cerebrovascular disease and encephalopathy were mainly related to severe clinical cases. In addition, we focus especially on the various concerned physiological routes, including BBB dysfunction, which transpired due to SARS-CoV-2 infection, direct and indirect effects of the virus on the brain, and also, the plausible mechanisms of viral entry to the nerve system. We also outline the characterisation, and the ongoing pharmaceutical applications of quantum dots as smart nanocarriers crossing the blood-brain barrier and their importance in neurological diseases, mainly SARS-CoV-2 related manifestations Moreover, the market status, six clinical trials recruiting quantum dots, and the challenges limiting the clinical application of QDs are highlighted.

Loss of bisecting GlcNAcylation on MCAM of bone marrow stoma determined pro-tumoral niche in MDS/AML

Bone marrow (BM) stroma plays key roles in supporting hematopoietic stem cell (HSC) growth. Glycosylation contributes to the interactions between HSC and surrounding microenvironment. We observed that bisecting N-acetylglucosamine (GlcNAc) structures, in BM stromal cells were significantly lower for MDS/AML patients than for healthy subjects. Malignant clonal cells delivered exosomal miR-188-5p to recipient stromal cells, where it suppressed bisecting GlcNAc by targeting MGAT3 gene. Proteomic analysis revealed reduced GlcNAc structures and enhanced expression of MCAM, a marker of BM niche. We characterized MCAM as a bisecting GlcNAc-bearing target protein, and identified Asn 56 as bisecting GlcNAc modification site on MCAM. MCAM on stromal cell surface with reduced bisecting GlcNAc bound strongly to CD13 on myeloid cells, activated responding ERK signaling, and thereby promoted myeloid cell growth. Our findings, taken together, suggest a novel mechanism whereby MDS/AML clonal cells generate a self-permissive niche by modifying glycosylation level of stromal cells.

CD146+ mural cells from infantile hemangioma display proangiogenic ability and adipogenesis potential in vitro and in xenograft models

Objective

Infantile hemangioma (IH), the most common infantile vascular neoplasm, is uniquely characterized by rapid proliferation followed by slow spontaneous involution lasting for years. In IH lesions, perivascular cells are the most dynamic cell subset during the transition from the proliferation phase to the involution phase, and we aimed to systematically study this kind of cell.

Methods and results

CD146-selective microbeads were used to isolate IH-derived mural-like cells (HemMCs). Mesenchymal markers of HemMCs were detected by flow cytometry, and the multilineage differentiation potential of HemMCs was detected by specific staining after conditioned culture. CD146-selected nonendothelial cells from IH samples showed characteristics of mesenchymal stem cells with distinct angiogenesis-promoting effects detected by transcriptome sequencing. HemMCs spontaneously differentiated into adipocytes 2 weeks after implantation into immunodeficient mice, and almost all HemMCs had differentiated into adipocytes within 4 weeks. HemMCs could not be induced to differentiate into endothelial cells in vitro. However, 2 weeks after implantation in vivo, HemMCs in combination with human umbilical vein endothelial cells (HUVECs) formed GLUT1⁺ IH-like blood vessels, which spontaneously involuted into adipose tissue 4 weeks after implantation.

Conclusions

In conclusion, we identified a specific cell subset that not only showed behavior consistent with the evolution of IH but also recapitulated the unique course of IH. Thus, we speculate that proangiogenic HemMCs may be a potential target for the construction of hemangioma animal models and the study of IH pathogenesis.

tRNA-like Transcripts from the NEAT1-MALAT1 Genomic Region Critically Influence Human Innate Immunity and Macrophage Functions

The evolutionary conserved NEAT1-MALAT1 gene cluster generates large noncoding transcripts remaining nuclear, while tRNA-like transcripts (mascRNA, menRNA) enzymatically generated from these precursors translocate to the cytosol. Whereas functions have been assigned to the nuclear transcripts, data on biological functions of the small cytosolic transcripts are sparse. We previously found NEAT1^-/- and MALAT1^-/- mice to display massive atherosclerosis and vascular inflammation. Here, employing selective targeted disruption of menRNA or mascRNA, we investigate the tRNA-like molecules as critical components of innate immunity. CRISPR-generated human ΔmascRNA and ΔmenRNA monocytes/macrophages display defective innate immune sensing, loss of cytokine control, imbalance of growth/angiogenic factor expression impacting upon angiogenesis, and altered cell-cell interaction systems. Antiviral response, foam cell formation/oxLDL uptake, and M1/M2 polarization are defective in ΔmascRNA/ΔmenRNA macrophages, defining first biological functions of menRNA and describing new functions of mascRNA. menRNA and mascRNA represent novel components of innate immunity arising from the noncoding genome. They appear as prototypes of a new class of noncoding RNAs distinct from others (miRNAs, siRNAs) by biosynthetic pathway and intracellular kinetics. Their NEAT1-MALAT1 region of origin appears as archetype of a functionally highly integrated RNA processing system.

CD146 interaction with integrin β1 activates LATS1-YAP signaling and induces radiation-resistance in breast cancer cells

Radiotherapy is an indispensable modality in comprehensive treatment of breast cancer. However, inherent or acquired radiation resistance of tumors compromises the efficacy of radiotherapy. Herein, we found that CD146, a unique epithelial-to-mesenchymal transition (EMT) inducer particularly highly expressed in triple-negative breast cancer (TNBC), is dramatically induced by ionizing irradiation. Further study demonstrates that CD146 promotes tumor cell radioresistance in vitro and in vivo. Specifically, we report the underlying mechanism that CD146 activates YAP protein, and drives its relocation from plasma to nucleus by regulating LATS1, and promoting abnormal DNA damage repair, as well as inducing EMT and stemness. Moreover, CD146 can form a novel co-receptor complex with integrin β1 and induces radiation-resistance in breast cancer. Dual inhibition of CD146 and integrin β1 activity had a stronger inhibitory effect on breast cancer tumor growth and synergistically increased their sensitivity to radiotherapy. This study identifies a unique function of CD146 implicates with integrin β1 and YAP signaling, contributing to radiation resistance. Targeted therapy against CD146 or inhibition of integrin β1 is a potential strategy to overcome radiotherapeutic resistance of breast cancer.

Knockdown of CD146 promotes endothelial-to-mesenchymal transition via Wnt/β-catenin pathway

Purpose

Cardiac fibrosis is characterized by the excessive deposition of extracellular matrix (ECM) proteins and leads to the maladaptive changes in myocardium. Endothelial cells (ECs) undergoing mesenchymal transition contributes to the occurrence and development of cardiac fibrosis. CD146 is an adhesion molecule highly expressed in ECs. The present study was performed to explore the role of CD146 in modulating endothelial to mesenchymal transition (EndMT).

Methods

C57BL/6 mice were subjected to subcutaneous implantation of osmotic minipump infused with angiotensin II (Ang Ⅱ). Adenovirus carrying CD146 short hairpin RNA (shRNA) or CD146 encoding sequence were infected into cultured human umbilical vein endothelial cells (HUVECs) followed by stimulation with Ang II or transforming growth factor-β1 (TGF-β1). Differentially expressed genes were revealed by RNA-sequencing (RNA-Seq) analysis. Gene expression was measured by quantitative real-time PCR, and protein expression and distribution were determined by Western blot and immunofluorescence staining, respectively.

Results

CD146 was predominantly expressed by ECs in normal mouse hearts. CD146 was upregulated in ECs but not fibroblasts and myocytes in hearts of Ang II-infused mice and in HUVECs stimulated with Ang Ⅱ. RNA-Seq analysis revealed the differentially expressed genes related to EndMT and Wnt/β-catenin signaling pathway. CD146 knockdown and overexpression facilitated and attenuated, respectively, EndMT induced by Ang II or TGF-β1. CD146 knockdown upregulated Wnt pathway-related genes including Wnt4, LEF1, HNF4A, FOXA1, SOX6, and CCND3, and increased the protein level and nuclear translocation of β-catenin.

Conclusions

Knockdown of CD146 exerts promotional effects on EndMT via activating Wnt/β-catenin pathway and the upregulation of CD146 might play a protective role against EndMT and cardiac fibrosis.

The pleiotropic role of galectin-3 in melanoma progression: Unraveling the enigma

Melanoma is a highly aggressive skin cancer with poor outcomes associated with distant metastasis. Intrinsic properties of melanoma cells alongside the crosstalk between melanoma cells and surrounding microenvironment determine the tumor behavior. Galectin-3 (Gal-3), a ß-galactoside-binding lectin, has emerged as a major effector in cancer progression, including melanoma behavior. Data from melanoma models and patient studies reveal that Gal-3 expression is dysregulated, both intracellularly and extracellularly, throughout the stages of melanoma progression. This review summarizes the most recent data and hypotheses on Gal-3 and its tumor-modulating functions, highlighting its role in driving melanoma growth, invasion, and metastatic colonization. It also provides insight into potential Gal-3-targeted strategies for melanoma diagnosis and treatment.

CD146 Defines a Mesenchymal Stromal Cell Subpopulation with Enhanced Suppressive Properties

Mesenchymal stromal cells (MSCs) are largely known for their immune-suppressive capacity, hence, their common use in the control of unwanted inflammation. However, novel concepts related to their biology, combined with the urgent need to identify MSC subpopulations with enhanced suppressive properties, drive the search for isolation protocols optimized for clinical applications. We show, in this study, that MSCs expressing high CD146 levels exhibit altered surface expression profiles of CD44 and secrete elevated levels of interleukin (IL)-6, amongst other factors. In addition, CD146^hi MSCs surpass the polyclonal parental populations in inhibiting alloreactive T cells in vitro, in both a soluble- and cell-contact-dependent manner. Despite the lack of CD146^hi MSC-mediated activation of peritoneal macrophages to release the suppressive factor IL-10 in vitro, their administration in animals with graft-versus-host disease alleviates inflammation and leads to 40% survival rate up to 7 weeks post-transplantation. This pronounced inhibitory property is driven by CD146-mediated in situ efferocytosis by myeloid cells. Altogether, this study provides the impetus to adopt an isolation protocol for MSCs based on a CD146 expression profile before their therapeutic use and suggests a major role played by CD146 as a novel “eat-me” signal, capable of enhancing MSC uptake by competent phagocytes.

CD146 increases stemness and aggressiveness in glioblastoma and activates YAP signaling

Glioblastoma (GBM), a highly malignant and lethal brain tumor, is characterized by diffuse invasion into the brain and chemo-radiotherapy resistance resulting in poor prognosis. In this study, we examined the involvement of the cell adhesion molecule CD146/MCAM in regulating GBM aggressiveness. Analyses of GBM transcript expression databases revealed correlations of elevated CD146 levels with higher glioma grades, IDH-wildtype and unmethylated MGMT phenotypes, poor response to chemo-radiotherapy and worse overall survival. In a panel of GBM stem cells (GSCs) variable expression levels of CD146 were detected, which strongly increased upon adherent growth. CD146 was linked with mesenchymal transition since expression increased in TGF-ß-treated U-87MG cells. Ectopic overexpression of CD146/GFP in GG16 cells enhanced the mesenchymal phenotype and resulted in increased cell invasion. Conversely, GSC23-CD146 knockouts had decreased mesenchymal marker expression and reduced cell invasion in transwell and GBM-cortical assembloid assays. Moreover, using GSC23 xenografted zebrafish, we found that CD146 depletion resulted in more compact delineated tumor formation and reduced tumor cell dissemination. Stem cell marker expression and neurosphere formation assays showed that CD146 increased the stem cell potential of GSCs. Furthermore, CD146 mediated radioresistance by stimulating cell survival signaling through suppression of p53 expression and activation of NF-κB. Interestingly, CD146 was also identified as an inducer of the oncogenic Yes-associated protein (YAP). In conclusion, CD146 carries out various pro-tumorigenic roles in GBM involving its cell surface receptor function, which include the stimulation of mesenchymal and invasive properties, stemness, and radiotherapy resistance, thus providing an interesting target for therapy.

Biomimetic Nanotherapeutics: Employing Nanoghosts to fight Melanoma

Melanoma is a cancer of melanocytes present at the basal layer of the skin. Nanomedicine has armed us with competent platform to manage such fatal neoplastic diseases. Nevertheless, it suffers from numerous pitfalls such as rapid clearance and opsonization of surface-functionalized carriers, biocompatibility and idiopathic reactions which could be difficult to predict in the patient. Biomimetic approach, a novel step towards personalized medicine bridges these drawbacks by employing endogenous cell membranes to traverse physiological barriers. Camouflaged carriers coated with natural cell membranes possess unique characteristics such as high circulatory periods, and the absence of allogenic and xenogenic responses. Proteins residing on the cell membranes render a diverse range of utilities to the coated nanoparticles including natural efficiency to identify cellular targets, homologous targeting, reticuloendothelial system evasion, biocompatibility and reduced adverse and idiopathic effects. In the present article, we have focused on cell membrane camouflaged nanocarriers for melanoma management. We have discussed various types of biomimetic systems, their processing and coating approaches, and their characterization. We have also enumerated novel avenues in melanoma treatment and the combination of biomimetic systems with smart nanoparticulate systems with the potential to bring breakthroughs in the near future. Additionally, immunotherapy-based biomimetic systems to combat melanoma have been highlighted. Hurdles towards clinical translation and ways to overcome them have been explained in detail.

The function of CD146 in human annulus fibrosus cells and mechanism of the regulation by TGF-β

The mouse outer annulus fibrosus (AF) was previously shown to contain CD146⁺ AF cells, while in vitro culture and exposure to transforming growth factor-beta (TGF-β) further increased the expression of CD146. However, neither the specific function of CD146 nor the underlying mechanism of TGF-β upregulation of CD146⁺ AF cells have been elucidated yet. In the current study, CD146 expression and its role in cultured human AF cells was investigated studying the cells' capacity for matrix contraction and gene expression of functional AF markers. In addition, TGF-β pathways were blocked by several pathway inhibitors and short hairpin RNAs (shRNAs) targeting SMAD and non-SMAD pathways to investigate their involvement in TGF-β-induced CD146 upregulation. Results showed that knockdown of CD146 led to reduction in AF cell-mediated collagen gel contraction, downregulation of versican and smooth muscle protein 22α (SM22α), and upregulation of scleraxis. TGF-β-induced CD146 upregulation was significantly blocked by inhibition of TGF-β receptor ALK5, and partially inhibited by shRNA against SMAD2 and SMAD4 and by an Protein Kinase B (AKT) inhibitor. Interestingly, the inhibition of extracellular signal-regulated kinases (ERK) pathway induced CD146 upregulation. In conclusion, CD146 was shown to be crucial to maintain the cell contractility of human AF cells in vitro. Furthermore, TGF-β upregulated CD146 via ALK5 signaling cascade, partially through SMAD2, SMAD4, and AKT pathway, whereas, ERK was shown to be a potential negative modulator. Our findings suggest that CD146 can potentially be used as a functional marker in AF repair strategies.

Inhibition of CD146 lessens uveal melanoma progression through reducing angiogenesis and vasculogenic mimicry

PURPOSE

Anti-angiogenesis drug therapy is ineffective in treating uveal melanoma since it only targets angiogenesis leaving vasculogenic mimicry aside. There is no effective clinical strategy targeting vasculogenic mimicry, yet. We show here that CD146 is a novel target to inhibit uveal melanoma progression since it regulates both uveal melanoma angiogenesis and vasculogenic mimicry activity.

METHODS

CD146 inhibition was achieved with its specific siRNAs or antibody AA98. Tube formation and migration of primary human retinal microvascular endothelial cells and tube-like structure formation, migration, invasion of uveal melanoma cells were evaluated after CD146 inhibition. The underlying mechanisms were investigated by Western blot and immunofluorescence. Finally, uveal melanoma cells were injected subretinally into the eyes of nude mice and AA98 was administrated. Tumor size was revealed by H&E staining, and angiogenesis and vasculogenic mimicry were evaluated with CD31-PAS staining.

RESULTS

CD146 inhibition induced declines in tube formation and migration of primary human retinal microvascular endothelial cells and tube-like structure formation of uveal melanoma cells. CD146 mediated VEGFR/AKT/p38/NF-κB and FAK/VE-cadherin signal cascades were partially responsible for these biological effects. CD146 blockade by siRNA or AA98 also resulted in inhibition of migration and invasion as well as EMT process of uveal melanoma cells. The physiological relevance of such declines was confirmed by showing that AA98 treatment markedly suppressed the tumor growth, angiogenesis and vasculogenic mimicry induced by implantation of uveal melanoma cells into the eyes of nude mice.

CONCLUSIONS

CD146 is a novel mediator of both angiogenesis and vasculogenic mimicry in uveal melanoma. Its antibody AA98 has the potency to be developed as a new antibody drug for treating uveal melanoma. Our results warrant further assessment of CD146 as a potential target to improve therapeutic management of uveal melanoma in a clinical setting.

A Novel Overall Survival Prediction Signature Based on Comprehensive Research in Prostate Cancer Bone Metastases

BACKGROUND

Prostate adenocarcinoma (PRAD)-related bone metastases are a leading source of morbidity and mortality; however, good diagnostic biomarkers are not known yet. The aim of this study was to identify biomarkers and prognostic indicators for the diagnosis and treatment of PRAD-associated bone metastases.

METHODS

By combining the data from The Cancer Genome Atlas(TCGA) and PRAD SU2C 2019, We performed a comprehensive analysis of the expression differences, biological functions, and interactions of genes associated with PRAD bone metastasis. Annotation, visualization, and integrated discovery were accomplished through the use of gene ontology enrichment and gene set enrichment analysis. The protein-protein interaction network was constructed using the STRING database, and the diagnostic value of prognostic genes was validated using receiver-operating-characteristic and Kaplan-Meier curves.

RESULTS

Six genes (DDX47, PRL17, AS3MT, KLRK1, ISLR, and S100A8) associated with PRAD bone metastases were identified; these had prognostic value as well. Among them, enrichment was observed for the biological processes extracellular matrix tissue, extracellular structural tissue, steroid hormone response, and cell oxidative detoxification. KEGG analysis revealed enrichment in interactions with extracellular matrix receptors, diseases including Parkinson's disease and dilated cardiomyopathy, and estrogen signaling pathways. The area under the curve values of 0.8938, 0.9885, and 0.979, obtained from time-dependent receiver-operating-characteristic curve analysis for 1, 3, and 5-year overall survival confirmed the good performance of the model under consideration. S100A8 expression was not detected in the normal prostate tissue but was detected in PRAD.

CONCLUSIONS

We identified ISLR as a potential biomarker for PRAD bone metastasis. Moreover, the genes identified to have prognostic value may act as therapeutic targets for PRAD bone metastasis.

CD146 as a promising therapeutic target for retinal and choroidal neovascularization diseases

Blood vessel dysfunction causes several retinal diseases, including diabetic retinopathy, familial exudative vitreoretinopathy, macular degeneration and choroidal neovascularization in pathological myopia. Vascular endothelial growth factor (VEGF)-neutralizing proteins provide benefits in most of those diseases, yet unsolved haemorrhage and frequent intraocular injections still bothered patients. Here, we identified endothelial CD146 as a new target for retinal diseases. CD146 expression was activated in two ocular pathological angiogenesis models, a laser-induced choroid neovascularization model and an oxygen-induced retinopathy model. The absence of CD146 impaired hypoxia-induced cell migration and angiogenesis both in cell lines and animal model. Preventive or therapeutic treatment with anti-CD146 antibody AA98 significantly inhibited hypoxia-induced aberrant retinal angiogenesis in two retinal disease models. Mechanistically, under hypoxia condition, CD146 was involved in the activation of NFκB, Erk and Akt signalling pathways, which are partially independent of VEGF. Consistently, anti-CD146 therapy combined with anti-VEGF therapy showed enhanced impairment effect of hypoxia-induced angiogenesis in vitro and in vivo. Given the critical role of abnormal angiogenesis in retinal and choroidal diseases, our results provide novel insights into combinatorial therapy for neovascular fundus diseases.

Use of Human Gingival Fibroblasts for Pre-Vascularization Strategies in Oral Tissue Engineering

BACKGROUND

Cocultures of human gingival fibrobasts (hGF) and endothelial cells could enhance regeneration and repair models as well as improve vascularization limitations in tissue engineering. The aim of this study was to assess if hGF could support formation of stable vessel-like networks.

METHODS

Explant primary hGF were isolated from gum surgical wastes collected from healthy patients with no history of periodontitis. Human umbilical vein endothelial cells (HUVEC) were two-dimensional (2D) and three-dimensional (3D) cocultured in vitro with hGF at a cell ratio of 1:1 and medium of 1:1 of their respective media during at least 31 days. Vessel quantification of HUVEC networks was performed. In order to investigate the pericyte-like properties of hGF, the expression of perivascular markers α-SMA, NG2, CD146 and PDGFR-β was studied using immunocytochemistry and flow cytometry on 2D cultures.

RESULTS

hGF were able to support a long-lasting HUVEC network at least 31 days, even in the absence of a bioreactor with flow. As observed, HUVEC started to communicate with each other from day 7, constructing a network. Their interconnection increased significantly between day 2 and day 21 and lasted beyond the 31 days of observation. Moreover, we tried to explain the stability of the networks obtained and showed that a small population of hGF in close vicinity of HUVEC networks expressed perivascular markers.

CONCLUSION

These findings highlight a new interesting property concerning hGF, accentuating their relevance in tissue engineering and periodontal regeneration. These promising results need to be confirmed using more 3D applications and in vivo testing.

Dendritic cell vaccine as a potential strategy to end the COVID-19 pandemic. Why should it be Ex Vivo?

INTRODUCTION

Developing a safe and efficacious vaccine that can induce broad and long-term immunity for SARS-CoV-2 infection is the most critical research to date. As the most potent APCs, dendritic cells (DCs) can induce a robust T cell immunity. In addition, DCs also play an essential role in COVID-19 pathogenesis, making them a potential vaccination target. However, the DCs-based vaccine with ex vivo loading has not yet been explored for COVID-19.

AREAS COVERED

This review aims to provide the rationale for developing a DCs-based vaccine with ex vivo loading of SARS-CoV-2 antigen. Here, we discuss the role of DCs in immunity and the effect of SARS-CoV-2 infection on DCs. Then, we propose the mechanism of the DCs-based vaccine in inducing immunity and highlight the benefits of ex vivo loading of antigen.

EXPERT OPINION

We make the case that an ex vivo loaded DC-based vaccination is appropriate for COVID-19 prevention.

Deep Visual Proteomics defines single-cell identity and heterogeneity

Despite the availabilty of imaging-based and mass-spectrometry-based methods for spatial proteomics, a key challenge remains connecting images with single-cell-resolution protein abundance measurements. Here, we introduce Deep Visual Proteomics (DVP), which combines artificial-intelligence-driven image analysis of cellular phenotypes with automated single-cell or single-nucleus laser microdissection and ultra-high-sensitivity mass spectrometry. DVP links protein abundance to complex cellular or subcellular phenotypes while preserving spatial context. By individually excising nuclei from cell culture, we classified distinct cell states with proteomic profiles defined by known and uncharacterized proteins. In an archived primary melanoma tissue, DVP identified spatially resolved proteome changes as normal melanocytes transition to fully invasive melanoma, revealing pathways that change in a spatial manner as cancer progresses, such as mRNA splicing dysregulation in metastatic vertical growth that coincides with reduced interferon signaling and antigen presentation. The ability of DVP to retain precise spatial proteomic information in the tissue context has implications for the molecular profiling of clinical samples.

Deep Visual Proteomics combines machine learning, automated image analysis and single-cell proteomics.

Overexpression of MCAM induced by SMYD2-H3K36me2 in breast cancer stem cell properties

BACKGROUND

Melanoma cell adhesion molecule (MCAM) is highly expressed in various malignancies. However, studies on the effects of MCAM on stemness of cancer stem cells are limited. Here, we aimed to explore the relationship between MCAM and stem cell phenotype in breast cancer (BC).

METHODS

We analyzed the genes differentially expressed in BC from the oncomine database, followed by TCGA-BRCA database validation. We then used gene set enrichment analysis to analyze the signaling pathways enriched to the relevant genes, followed by loss-of-function experiments to analyze the role of MCAM in the growth of BC cells and the maintenance of stem cell properties. We analyzed the cause for the MCAM overexpression using ChIP-seq and clarified the upstream mechanism by constructing SE-Deleted cells. Finally, the role of SMYD2 in the growth of BC cells and the maintenance of stem cell properties were verified by rescue experiments.

RESULTS

MCAM was significantly overexpressed in BC, which predicted somber prognosis in patients. Knockdown of MCAM drastically hindered the growth and metastasis of BC cells in vitro and in vivo. Subsequently, the MCAM promoter was observed to have significant H3K36me2 modification and that SMYD2 could significantly promote the expression of MCAM. In addition, further overexpression of SMYD2 in cells with MCAM knockdown increased MCAM expression and promoted the growth as well as stemness of BC cells.

CONCLUSION

SMYD2 can elevate the expression of MCAM by promoting its H3K36me2 modification, which in turn expedites the growth and stem cell properties of BC cells.