The Role of SMAD2/3 in Human Embryonic Stem Cells

Uncovering the role of aquaporin and chromobox family members as potential biomarkers in head and neck squamous cell carcinoma via integrative multiomics and in silico approach

Head and neck squamous cell carcinoma (HNSC) is a diverse group of tumors arising from oral cavity, oropharynx, larynx, and hypopharynx squamous epithelium, posing significant morbidity. Aquaporins (AQPs) are membrane proteins forming water channels, some associated with carcinomas. Chromobox (CBX) family is known to modulate physiological and oncological processes. In our study, we analyzed AQPs and CBXs having significant expression followed by their prognostic and mutational assessment. Next, we performed enrichment and tumor infiltration analysis followed by HPA validation. Lastly, we established a 3-node miRNA-TF-mRNA regulatory network and performed protein-protein docking of the highest-degree subnetwork motif between TF and mRNA. Significant upregulation of CBX3/2 and downregulation of AQP3/5/7 correlated with poor overall survival (OS) in HNSC patients. The most significant pathway, GO-BP, GO-MF, and GO-CC terms associated with AQP3 and CBX3 were passive transport by aquaporins, response to vitamin, glycerol channel activity, and condensed chromosome, centromeric region. AQP3 negatively correlated with [Formula: see text] T cells, positively with [Formula: see text] T cells and B cells, and negatively with tumor purity, whereas CBX3 positively correlated with [Formula: see text] T cells, negatively with [Formula: see text] T cells and B cells, and positively with tumor purity. Three-node miRNA-TF-mRNA regulatory network revealed a highest-degree subnetwork motif comprising one TF (SMAD3), one miRNA (miR-423-5p), and one mRNA (AQP3). Protein-protein interaction studies suggested a direct interaction between AQP3 and Smad3 proteins. We concluded that AQP3 and CBX3 hold potential as treatment strategies and individual prognostic biomarkers, while further protein-protein interaction studies of AQP3 could offer insights into its interactions with Smad3 proteins.

Investigation on mRNA expression and genetic variation within goat SMAD2 gene and its association with litter size

The SMAD family member 2 (SMAD2), a member of the TGF-beta superfamily, executes a significant part in the oogenesis and ovulation process. A genome-wide selective sweep analysis also found SMAD2 was different in the fertility groups of Laoshan dairy goats; whether this gene was linked to litter size was unknown. Therefore, SMAD2 was chosen to study its effects on Shaanbei white cashmere goat reproduction and mRNA expression profile. Herein, the mRNA expression level of SMAD2 was firstly determined in female goat tissues, revealing significant differences in mRNA levels of different tissues (p < 0.05), including ovary tissue, indicating a potential role for SMAD2 in goat prolificacy. Then, using six pairs of primers, only one indel locus (P3-Del-12-bp) was found to be polymorphic in goat SMAD2 (n = 501). ANOVA also revealed that a P3-Del-12-bp deletion was significantly related to first-born litter size (p = 0.037). The Chi-square (χ2) test revealed that the ID genotype was significantly more prevalent in mothers with multiple lambs (p = 0.01), indicating that heterozygous individuals (ID) are more likely to produce multiple lambs. Our findings suggest that the SMAD2 gene's P3-Del-12-bp deletion could be used to improve goat breeds by assisting with litter size selection.

The first identification and functional analysis of two drosophila mothers against decapentaplegic protein genes (SpSmad1 and SpSmad2/3) and their involvement in the innate immune response in Scylla paramamosain

Smad，a member of the TGF-β superfamily，controls cell proliferation，growth and guiding cell differentiation, thus playing a crucial role in diseases. However, the presence as well as specific function of Smad in crabs is still unknown. In this study, two Smads (Smad1 and Smad2/3) were identified for the first time from the mud crab Scylla paramamosain. The complete open reading frames of SpSmad1 and SpSmad2/3 were 1,497bp and 1,338bp, encoding deduced proteins of 498 and 445 amino acids respectively. Moreover, under the administration of Vibrio alginolyticus and WSSV, the relative expression levels of SpSmad1 and SpSmad2/3 were significantly increased, indicating their involvement in the innate immune response of mud crabs. Knockdown of SpSmad1 and SpSmad2/3 in vivo not only led to the increasement of the expressions of NF-κB signaling genes and antimicrobial peptides genes, but also significantly affected the bacterial clearance process of mud crabs. Additionally, overexpression of SpSmad1 and SpSmad2/3 in HEK293T cells could markedly activate NF-κB signaling. These results indicated that Smad1 and Smad2/3 participated in the innate immunity of Scylla paramamosain, and might provide a better understanding of the presence and immune regulatory functions of Smad1 and Smad2/3 in crabs and even invertebrates.

BRD9-mediated control of the TGF-β/Activin/Nodal pathway regulates self-renewal and differentiation of human embryonic stem cells and progression of cancer cells

Bromodomain-containing protein 9 (BRD9) is a specific subunit of the non-canonical SWI/SNF (ncBAF) chromatin-remodeling complex, whose function in human embryonic stem cells (hESCs) remains unclear. Here, we demonstrate that impaired BRD9 function reduces the self-renewal capacity of hESCs and alters their differentiation potential. Specifically, BRD9 depletion inhibits meso-endoderm differentiation while promoting neural ectoderm differentiation. Notably, supplementation of NODAL, TGF-β, Activin A or WNT3A rescues the differentiation defects caused by BRD9 loss. Mechanistically, BRD9 forms a complex with BRD4, SMAD2/3, β-CATENIN and P300, which regulates the expression of pluripotency genes and the activity of TGF-β/Nodal/Activin and Wnt signaling pathways. This is achieved by regulating the deposition of H3K27ac on associated genes, thus maintaining and directing hESC differentiation. BRD9-mediated regulation of the TGF-β/Activin/Nodal pathway is also demonstrated in the development of pancreatic and breast cancer cells. In summary, our study highlights the crucial role of BRD9 in the regulation of hESC self-renewal and differentiation, as well as its participation in the progression of pancreatic and breast cancers.

Neurodevelopmental disorders and cancer networks share pathways, but differ in mechanisms, signaling strength, and outcome

Epidemiological studies suggest that individuals with neurodevelopmental disorders (NDDs) are more prone to develop certain types of cancer. Notably, however, the case statistics can be impacted by late discovery of cancer in individuals afflicted with NDDs, such as intellectual disorders, autism, and schizophrenia, which may bias the numbers. As to NDD-associated mutations, in most cases, they are germline while cancer mutations are sporadic, emerging during life. However, somatic mosaicism can spur NDDs, and cancer-related mutations can be germline. NDDs and cancer share proteins, pathways, and mutations. Here we ask (i) exactly which features they share, and (ii) how, despite their commonalities, they differ in clinical outcomes. To tackle these questions, we employed a statistical framework followed by network analysis. Our thorough exploration of the mutations, reconstructed disease-specific networks, pathways, and transcriptome levels and profiles of autism spectrum disorder (ASD) and cancers, point to signaling strength as the key factor: strong signaling promotes cell proliferation in cancer, and weaker (moderate) signaling impacts differentiation in ASD. Thus, we suggest that signaling strength, not activating mutations, can decide clinical outcome.

Effects of low doses of methylmercury (MeHg) exposure on definitive endoderm cell differentiation in human embryonic stem cells

Fetal development is one of the most sensitive windows to methylmercury (MeHg) toxicity. Laboratory and epidemiological studies have shown a dose-response relationship between fetal MeHg exposure and neuro performance in different life stages from infants to adults. In addition, MeHg exposure has been reported to be associated with disorders in endoderm-derived organs, such as morphological changes in liver cells and pancreatic cell dysfunctions. However, the mechanisms of the effects of MeHg on non-neuronal organs or systems, especially during the early development of endoderm-derived organs, remain unclear. Here we determined the effects of low concentrations of MeHg exposure during the differentiation of definitive endoderm (DE) cells from human embryonic stem cells (hESCs). hESCs were exposed to MeHg (0, 10, 100, and 200 nM) that covers the range of Hg concentrations typically found in human maternal blood during DE cell induction. Transcriptomic analysis showed that sub-lethal doses of MeHg exposure could alter global gene expression patterns during hESC to DE cell differentiation, leading to increased expression of endodermal genes/proteins and the over-promotion of endodermal fate, mainly through disrupting calcium homeostasis and generating ROS. Bioinformatic analysis results suggested that MeHg exerts its developmental toxicity mainly by disrupting ribosome biogenesis during early cell lineage differentiation. This disruption could lead to aberrant growth or dysfunctions of the developing endoderm-derived organs, and it may be the underlying mechanism for the observed congenital diseases later in life. Based on the results, we proposed an adverse outcome pathway for the effects of MeHg exposure during human embryonic stem cells to definitive endoderm differentiation.

Fatty acid synthesis and oxidation regulate human endoderm differentiation by mediating SMAD3 nuclear localization via acetylation

Metabolic remodeling is one of the earliest events that occur during cell differentiation. Here, we define fatty acid metabolism as a key player in definitive endoderm differentiation from human embryonic stem cells. Fatty acid β-oxidation is enhanced while lipogenesis is decreased, and this is due to the phosphorylation of lipogenic enzyme acetyl-CoA carboxylase by AMPK. More importantly, inhibition of fatty acid synthesis by either its inhibitors or AMPK agonist significantly promotes human endoderm differentiation, while blockade of fatty acid oxidation impairs differentiation. Mechanistically, reduced de novo fatty acid synthesis and enhanced fatty acid β-oxidation both contribute to the accumulation of intracellular acetyl-CoA, which guarantees the acetylation of SMAD3 and further causes nuclear localization to promote endoderm differentiation. Thus, our current study identifies a fatty acid synthesis/oxidation shift during early differentiation and presents an instructive role for fatty acid metabolism in regulating human endoderm differentiation.

Identification of Key lncRNAs, circRNAs, and mRNAs in Osteoarthritis via Bioinformatics Analysis

Osteoarthritis (OA) is a common degenerative joint disorder that adversely affects the quality of life of patients. Identification of novel diagnostic biomarkers is pivotal for the early detection and prevention of OA. Dataset GSE185059 was selected from Gene Expression Omnibus database to obtain differentially expressed lncRNAs (DE-lncRNAs), mRNAs (DE-mRNAs), and circRNAs (DE-circRNAs) between OA and normal samples. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses as well as protein-protein interaction (PPI) network construction of DE-mRNAs were conducted. Hub genes were identified from PPI networks and validated by RT-qPCR. starBase database was utilized for predicting miRNAs binding with hub genes, selected DE-lncRNAs and DE-circRNAs, respectively. The competing endogenous RNA (ceRNA) networks were constructed. A total of 818 DE-mRNAs, 191 DE-lncRNAs, and 2053 DE-circRNAs were identified. The DE-mRNAs were significantly enriched in several inflammation-related GO terms and KEGG pathways such as positive regulation of cell-cell adhesion, TNF-alpha signaling pathway and NF-kappa B signaling pathway. Thirteen hub genes were identified, which were CFTR, GART, SMAD2, NCK1, TJP1, UBE2D1, EFTUD2, PRKACB, IL10, SNRPG, CHD4, RPS24, and SRSF6. OA-related DE-lncRNA/circRNA-miRNA-hub gene networks were constructed. We identified 13 hub genes and constructed the ceRNA networks related to OA, providing a theoretical basis for further research.

The constitutively active pSMAD2/3 relatively improves the proliferation of chicken primordial germ cells

In many multicellular organisms, mature gametes originate from primordial germ cells (PGCs). Improvements in the culture of PGCs are important not only for developmental biology research, but also for preserving endangered species, and for genome editing and transgenic animal technologies. SMAD2/3 appear to be powerful regulators of gene expression; however, their potential positive impact on the regulation of PGC proliferation has not been taken into consideration. Here, the effect of TGF-β signaling as the upstream activator of SMAD2/3 transcription factors was evaluated on chicken PGCs' proliferation. For this, chicken PGCs at stages 26-28 Hamburger-Hamilton were obtained from the embryonic gonadal regions and cultured on different feeders or feeder-free substrates. The results showed that TGF-β signaling agonists (IDE1 and Activin-A) improved PGC proliferation to some extent while treatment with SB431542, the antagonist of TGF-β, disrupted PGCs' proliferation. However, the transfection of PGCs with constitutively active SMAD2/3 (SMAD2/3CA) resulted in improved PGC proliferation for more than 5 weeks. The results confirmed the interactions between overexpressed SMAD2/3CA and pluripotency-associated genes NANOG, OCT4, and SOX2. According to the results, the application of SMAD2/3CA could represent a step toward achieving an efficient expansion of avian PGCs.

LINC01232 promotes lung squamous cell carcinoma progression through modulating miR-181a-5p/SMAD2 axis

BACKGROUND

LINC01232 has been implicated in the progression of multiple malignancies. Yet, the function of LINC01232 in the carcinogenesis of lung squamous cell carcinoma (LUSC) remains unclear. This study aims to examine the role LINC01232 plays in LUSC progression.

METHODS

mRNA and protein levels were assessed using qRT-PCR and western blot, respectively. Cell proliferation was assessed by CCK-8 and colony formation assays. Cell migration and invasion were evaluated by transwell assay. The interactions between LINC01232, miR-181a-5p, and SMAD2 were assessed using luciferase reporter, RNA pull-down, and RNA immunoprecipitation (RIP) assays. The subcellular distribution of LINC01232 was examined by cytosolic/nuclear fractionation assay RESULTS: LINC01232 was upregulated in both LUSC tissues and cell lines. Knockdown of LINC01232 impaired cell proliferation, migration and invasion capability in H1229 and A549 cells, a phenotype that could be reversed by miR-181a-5p silencing. In addition, LINC01232 silencing reduced levels of N-cadherin, Vimentin, and Snail in H1229 and A549 cells, but increased the level of E-cadherin, which can be abrogated by miR-181a-5p inhibitors.

CONCLUSIONS

In summary, our study demonstrates that LINC01232 expression increases in LUSC tissues and cell lines and promotes LUSC progression by modulating the miR-181a-5p/SMAD2 signaling, providing new potential drug targets for LUSC treatment.

Biomimetic hydrogel blanket for conserving and recovering intrinsic cell properties

BACKGROUND

Cells in the human body experience different growth environments and conditions, such as compressive pressure and oxygen concentrations, depending on the type and location of the tissue. Thus, a culture device that emulates the environment inside the body is required to study cells outside the body.

METHODS

A blanket-type cell culture device (Direct Contact Pressing: DCP) was fabricated with an alginate-based hydrogel. Changes in cell morphology due to DCP pressure were observed using a phase contrast microscope. The changes in the oxygen permeability and pressure according to the hydrogel concentration of DCP were analyzed. To compare the effects of DCP with normal or artificial hypoxic cultures, cells were divided based on the culture technique: normal culture, DCP culture device, and artificial hypoxic environment. Changes in phenotype, genes, and glycosaminoglycan amounts according to each environment were evaluated. Based on this, the mechanism of each culture environment on the intrinsic properties of conserving chondrocytes was suggested.

RESULTS

Chondrocytes live under pressure from the surrounding collagen tissue and experience a hypoxic environment because collagen inhibits oxygen permeability. By culturing the chondrocytes in a DCP environment, the capability of DCP to produce a low-oxygen and physical pressure environment was verified. When human primary chondrocytes, which require pressure and a low-oxygen environment during culture to maintain their innate properties, were cultured using the hydrogel blanket, the original shapes and properties of the chondrocytes were maintained. The intrinsic properties could be recovered even in aged cells that had lost their original cell properties.

CONCLUSIONS

A DCP culture method using a biomimetic hydrogel blanket provides cells with an adjustable physical pressure and a low-oxygen environment. Through this technique, we could maintain the original cellular phenotypes and intrinsic properties of human primary chondrocytes. The results of this study can be applied to other cells that require special pressure and oxygen concentration control to maintain their intrinsic properties. Additionally, this technique has the potential to be applied to the re-differentiation of cells that have lost their original properties.

miR-106b-5p Intensifies the Proliferative Potential of Spermatogonial Stem Cells as a Prerequisite for Male Infertility Treatment

Although numerous studies have investigated the molecular basis of male infertility, various aspects of this area have remained uncovered. Over the past years, researchers have reported the significant potential of miRNAs in posttranscriptional regulatory roles. By targeting mRNAs, these notable molecules can modulate the processes related to male infertility. On the other side, the outstanding potential of male germline stem cells, SSCs, includes their application in infertility treatment. SSCs retain normal spermatogenesis and fertility by adjusting both SSC self-renewal and differentiation. Therefore, for the characterization and manipulation of SSCs, effective and efficient in vitro culture methods are essential in supporting their maintenance and development. In this regard, the present investigation was undertaken to evaluate the impact of one of the recently conspicuous miRNAs, miR-106b, in SSCs enrichment. As a result, we first found that the SSCs induced with miR-106b-5p highly express TGF-β1, which is known as a regulator of epigenetic modifiers and downstream genes. We next sought to show that self-renewal markers, including c-Myc, Oct-4, and Sox2, are increased in the induced SSC group. The intended miRNA also induced the inhibitor of differentiation 4 (ID4) and aided to remain unmethylated in SSCs. Additionally, for the tumorigenicity possibility of the manipulation, we indicated that PTEN, a tumor-suppressor gene, expressed remarkably in the induced SSCs. In conclusion, our findings showed that miR-106b-5p enhances the proliferative potential of SSCs, making it a substantial factor for therapeutic strategies of male infertility.

Pathophysiology and Emerging Molecular Therapeutic Targets in Heterotopic Ossification

The term heterotopic ossification (HO) describes bone formation in tissues where bone is normally not present. Musculoskeletal trauma induces signalling events that in turn trigger cells, probably of mesenchymal origin, to differentiate into bone. The aetiology of HO includes extremely rare but severe, generalised and fatal monogenic forms of the disease; and as a common complex disorder in response to musculoskeletal, neurological or burn trauma. The resulting bone forms through a combination of endochondral and intramembranous ossification, depending on the aetiology, initiating stimulus and affected tissue. Given the heterogeneity of the disease, many cell types and biological pathways have been studied in efforts to find effective therapeutic strategies for the disorder. Cells of mesenchymal, haematopoietic and neuroectodermal lineages have all been implicated in the pathogenesis of HO, and the emerging dominant signalling pathways are thought to occur through the bone morphogenetic proteins (BMP), mammalian target of rapamycin (mTOR), and retinoic acid receptor pathways. Increased understanding of these disease mechanisms has resulted in the emergence of several novel investigational therapeutic avenues, including palovarotene and other retinoic acid receptor agonists and activin A inhibitors that target both canonical and non-canonical signalling downstream of the BMP type 1 receptor. In this article we aim to illustrate the key cellular and molecular mechanisms involved in the pathogenesis of HO and outline recent advances in emerging molecular therapies to treat and prevent HO that have had early success in the monogenic disease and are currently being explored in the common complex forms of HO.

Melatonin enhances osteoblastogenesis of senescent bone marrow stromal cells through NSD2-mediated chromatin remodelling

BACKGROUND

Aging-associated osteoporosis is frequently seen in the elderly in clinic, but efficient managements are limited because of unclear nosogenesis. The current study aims to investigate the role of melatonin on senescent bone marrow stromal cells (BMSCs) and the underlying regulating mechanism.

METHODS

Melatonin levels were tested by ELISA. Gene expression profiles were performed by RNA-sequencing, enrichment of H3K36me2 on gene promoters was analyzed by Chromatin Immunoprecipitation Sequencing (ChIP-seq), and chromatin accessibility was determined by Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq). Osteogenesis of BMSCs in vitro was measured by Alizarin Red and Alkaline Phosphatase staining, and in vivo effects of melatonin was assessed by histological staining and micro computed tomography (micro-CT) scan. Correlation of NSD2 expression and severity of senile osteoporosis patients were analyzed by Pearson correlation.

RESULTS

Melatonin levels were decreased during aging in human bone marrow, accompanied by downregulation of the histone methyltransferase nuclear receptor binding SET domain protein 2 (NSD2) expression in the senescent BMSCs. Melatonin stimulated the expression of NSD2 through MT1/2-mediated signaling pathways, resulting in the rebalancing of H3K36me2 and H3K27me3 modifications to increase chromatin accessibility of the osteogenic genes, runt-related transcription factor 2 (RUNX2) and bone gamma-carboxyglutamate protein (BGLAP). Melatonin promoted osteogenesis of BMSCs in vitro, and alleviates osteoporosis progression in the aging mice. In clinic, severity of senile osteoporosis (SOP) was negatively correlated with melatonin level in bone marrow, as well as NSD2 expression in BMSCs. Similarly, melatonin remarkably enhanced osteogenic differentiation of BMSCs derived from SOP patients in vitro.

CONCLUSIONS

Collectively, our study dissects previously unreported mechanistic insights into the epigenetic regulating machinery of melatonin in meliorating osteogenic differentiation of senescent BMSC, and provides evidence for application of melatonin in preventing aging-associated bone loss.

Landscape of tissue-specific RNA Editome provides insight into co-regulated and altered gene expression in pigs (Sus-scrofa)

RNA editing generates genetic diversity in mammals by altering amino acid sequences, miRNA targeting site sequences, influencing the stability of targeted RNAs, and causing changes in gene expression. However, the extent to which RNA editing affect gene expression via modifying miRNA binding site remains unexplored. Here, we first profiled the dynamic A-to-I RNA editome across tissues of Duroc and Luchuan pigs. The RNA editing events at the miRNA binding sites were generated. The biological function of the differentially edited gene in skeletal muscle was further characterized in pig muscle-derived satellite cells. RNA editome analysis revealed a total of 171,909 A-to-I RNA editing sites (RESs), and examination of its features showed that these A-to-I editing sites were mainly located in SINE retrotransposons PRE-1/Pre0_SS element. Analysis of differentially edited sites (DESs) revealed a total of 4,552 DESs across tissues between Duroc and Luchuan pigs, and functional category enrichment analysis of differentially edited gene (DEG) sets highlighted a significant association and enrichment of tissue-developmental pathways including TGF-beta, PI3K-Akt, AMPK, and Wnt signaling pathways. Moreover, we found that RNA editing events at the miRNA binding sites in the 3'-UTR of HSPA12B mRNA could prevent the miRNA-mediated mRNA downregulation of HSPA12B in the muscle-derived satellite (MDS) cell, consistent with the results obtained from the Luchuan skeletal muscle. This study represents the most systematic attempt to characterize the significance of RNA editing in regulating gene expression, particularly in skeletal muscle, constituting a new layer of regulation to understand the genetic mechanisms behind phenotype variance in animals.Abbreviations: A-to-I: Adenosine-to-inosine; ADAR: Adenosine deaminase acting on RNA; RES: RNA editing site; DEG: Differentially edited gene; DES: Differentially edited site; FDR: False discovery rate; GO: Gene Ontology; KEGG: Kyoto Encyclopaedia of Genes and Genomes; MDS cell: musclederived satellite cell; RPKM: Reads per kilobase of exon model in a gene per million mapped reads; UTR: Untranslated coding regions.

In Silico Analysis to Explore Lineage-Independent and -Dependent Transcriptional Programs Associated with the Process of Endothelial and Neural Differentiation of Human Induced Pluripotent Stem Cells

Despite a major interest in understanding how the endothelial cell phenotype is established, the underlying molecular basis of this process is not yet fully understood. We have previously reported the generation of induced pluripotent stem cells (iPS) from human umbilical vein endothelial cells and differentiation of the resulting HiPS back to endothelial cells (Ec-Diff), as well as neural (Nn-Diff) cell lineage that contained both neurons and astrocytes. Furthermore, the identities of these cell lineages were established by gene array analysis. Here, we explored the same arrays to gain insight into the gene alteration processes that accompany the establishment of endothelial vs. non-endothelial neural cell phenotypes. We compared the expression of genes that code for transcription factors and epigenetic regulators when HiPS is differentiated into these endothelial and non-endothelial lineages. Our in silico analyses have identified cohorts of genes that are similarly up- or downregulated in both lineages, as well as those that exhibit lineage-specific alterations. Based on these results, we propose that genes that are similarly altered in both lineages participate in priming the stem cell for differentiation in a lineage-independent manner, whereas those that are differentially altered in endothelial compared to neural cells participate in a lineage-specific differentiation process. Specific GATA family members and their cofactors and epigenetic regulators (DNMT3B, PRDM14, HELLS) with a major role in regulating DNA methylation were among participants in priming HiPS for lineage-independent differentiation. In addition, we identified distinct cohorts of transcription factors and epigenetic regulators whose alterations correlated specifically with the establishment of endothelial vs. non-endothelial neural lineages.

New Insights into Cancer Targeted Therapy: Nodal and Cripto-1 as Attractive Candidates

The transforming growth factor beta (TGF-β) signaling is fundamental for correct embryonic development. However, alterations of this pathway have been correlated with oncogenesis, tumor progression and sustaining of cancer stem cells (CSCs). Cripto-1 (CR-1) and Nodal are two embryonic proteins involved in TGF-β signaling. Their expression is almost undetectable in terminally differentiated cells, but they are often re-expressed in tumor cells, especially in CSCs. Moreover, cancer cells that show high levels of CR-1 and/or Nodal display more aggressive phenotypes in vitro, while in vivo their expression correlates with a worse prognosis in several human cancers. The ability to target CSCs still represents an unmet medical need for the complete eradication of certain types of tumors. Given the prognostic role and the selective expression of CR-1 and Nodal on cancer cells, they represent archetypes for targeted therapy. The aim of this review is to clarify the role of CR-1 and Nodal in cancer stem populations and to summarize the current therapeutic strategy to target CSCs using monoclonal antibodies (mAbs) or other molecular tools to interfere with these two proteins.

In the presence of TGF-β1, Asperosaponin VI promotes human mesenchymal stem cell differentiation into nucleus pulposus like- cells

Background

The regeneration of nucleus pulposus (NP) cells is an effective method to prevent intervertebral disc degeneration (IVDD). In this study, we investigated the role of Asperosaponin VI (ASA VI), isolated from a traditional Chinese medicine (TCM), the root of Dipsacus asper Wall, in promoting human mesenchymal stem cell (HMSC) proliferation and differentiation into NP-like cells and explored the possible mechanism of action.

Methods

The effects of ASA VI on HMSC viability and proliferation were determined by the XTT method and EDU staining. Then, Real-time qPCR, immunocytochemistry and immunofluorescence assays were used to measure the effect of ASA VI on the expression of extracellular matrix (ECM) components, such as COL2A1, aggrecan, SOX9, KRT19, PAX1, and glycosaminoglycans (GAGs), in NP cells. In addition, Western blot assay was used to measure the expression of p-ERK1/2 and p-smad2/3.

Results

ASA VI was able to promote the proliferation and differentiation of HMSCs into NP-like cells, and the optimum concentration was 1 mg/L. Western blot assay indicated that the possible mechanism might be related to the activation of p-ERK1 / 2 and p-Smad2 / 3.

Conclusions

ASA VI can promote the proliferation and differentiation of HMSCs into NP-like cells, which can potentially be used as a treatment for IVDD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-020-03169-y.