Human placenta-derived multipotent mesenchymal stromal cells involved in placental angiogenesis via the PDGF-BB and STAT3 pathways

Vertical Intrauterine Bovine and Ovine Papillomavirus Coinfection in Pregnant Cows

There is very little information available about transplacental infections by the papillomavirus in ruminants. However, recent evidence has emerged of the first report of vertical infections of bovine papillomavirus (BPV) in fetuses from naturally infected, pregnant cows. This study reports the coinfection of BPV and ovine papillomavirus (OaPV) in bovine fetuses from infected pregnant cows suffering from bladder tumors caused by simultaneous, persistent viral infections. Some molecular mechanisms involving the binary complex composed of Eras and platelet-derived growth factor β receptor (PDGFβR), by which BPVs and OaPVs contribute to reproductive disorders, have been investigated. A droplet digital polymerase chain reaction (ddPCR) was used to detect and quantify the nucleic acids of the BPVs of the Deltapapillomavirus genus (BPV1, BPV2, BPV13, and BPV14) and OaPVs belonging to the Deltapapillomavirus (OaPV1, OaPV2, and OaPV4) and Dyokappapapillomavirus (OaPV3) genera in the placenta and fetal organs (heart, lung, liver, and kidneys) of four bovine fetuses from four pregnant cows with neoplasia of the urinary bladder. A papillomaviral evaluation was also performed on the bladder tumors and peripheral blood of these pregnant cows. In all fetal and maternal samples, the genotype distribution of BPVs and OaPVs were evaluated using both their DNA and RNA. A BPV and OaPV coinfection was seen in bladder tumors, whereas only BPV infection was found in peripheral blood. The genotype distribution of both the BPVs and OaPVs detected in placentas and fetal organs indicated a stronger concordance with the viral genotypes detected in bladder tumors rather than in peripheral blood. This suggests that the viruses found in placentas and fetuses may have originated from infected bladders. Our study highlights the likelihood of vertical infections with BPVs and OaPVs and emphasizes the importance of gaining further insights into the mechanisms and consequences of this exposure. This study warrants further research as adverse pregnancy outcomes are a major source of economic losses in cattle breeding.

Mesenchymal Stem Cell Derived Exosomes Therapy in Diabetic Wound Repair

Nowadays, refractory diabetic wounds cause a worldwide medical burden. Mesenchymal stem cells derived exosomes (MSC-Exos) show promise as a solid alternative to existing therapeutics in the latest researches, since MSC-Exos share similar biologic activity but less immunogenicity when compared with MSCs. To facilitate further understanding and application, it is essential to summarize the current progress and limitations of MSC-Exos in the treatment of diabetic wounds. In this review, we introduce the effects of different MSC-Exos on diabetic wounds according to their origins and contents and discuss the specific experimental conditions, target wound cells/pathways, and specific mechanisms. In addition, this paper focuses on the combination of MSC-Exos and biomaterials, which improves the efficacy and utilization of MSC-Exos therapy. Together, exosome therapy has high clinical value and application prospects, both in its role and in combination with biomaterials, while novel drugs or molecules loaded into exosomes as carriers targeting wound cells will be development trends.

Placental treatment with insulin-like growth factor 1 via nanoparticle differentially impacts vascular remodeling factors in guinea pig sub-placenta/decidua

Clinically, fetal growth restriction (FGR) is only detectable in later gestation, despite pathophysiological establishment likely earlier in pregnancy. Additionally, there are no effective in utero treatment options for FGR. We have developed a nanoparticle to deliver human insulin-like 1 growth factor (hIGF-1) in a trophoblast-specific manner which results in increased expression of hIGF-1. IGF-1 signaling in the placenta regulates multiple developmental processes including trophoblast invasion and maternal vascular remodeling, both of which can be diminished in the FGR placenta. We aimed to determine the effects of short-term hIGF-1 nanoparticle treatment on sub-placenta/decidua trophoblast signaling mechanisms in FGR and under normal growth conditions. Using the guinea pig maternal nutrient restriction (MNR) model of FGR, ultrasound-guided, intra-placenta injections of hIGF-1 nanoparticle were performed at gestational day 30-33, and dams sacrificed 5 days later. Sub-placenta/decidua tissue was separated from placenta for further analyses. Western blot was used to analyze protein expression of ERK/AKT/mTOR signaling proteins (phospho-Erk (pERK), phospho-Akt (pAKT), raptor, rictor and deptor). qPCR was used to analyze gene expression of vascular/remodeling factors [vascular endothelial growth factor (Vegf), placenta growth factor (Pgf), platelet-derived growth factor (Pdgf)) and tight junction/adhesion proteins (claudin 5 (Cldn5), p-glycoprotein (Abcb1), occludin (Ocln) and tight junction protein 1 (Zo1)]. MNR reduced expression of pERK, PdgfB and Cldn5, and increased expression of Ocln and Zo1 in the sub-placenta/decidua. In MNR + hIGF1 nanoparticle sub-placenta/decidua, expression of PdgfB, Ocln and Zo1 was normalized, whilst pAkt, VegfB, Vegf receptor 1 and PdgfB receptor were increased compared to MNR. In contrast, hIGF-1 nanoparticle treatment of normal placentas reduced expression of pERK, raptor and increased expression of the mTOR inhibitor deptor. This was associated with reduced expression of VegfA, Plgf, and PdgfB. Here we have shown that the impact of hIGF-1 nanoparticle treatment is dependent on pregnancy environment. Under MNR/FGR, hIGF-1 nanoparticle treatment triggers increased expression of growth factors and normalization of EMT factors. However, under normal conditions, the response of the placenta is to decrease AKT/mTOR signaling and growth factor expression to achieve homeostasis.

Exosomal microRNA-342-5p from human umbilical cord mesenchymal stem cells inhibits preeclampsia in rats

We aimed to investigate the inhibitory effect of human umbilical cord mesenchymal stem cell (hucMSC)-derived exosomes (hucMSC-Exos) transmitting microRNA-342-5p (miR-342-5p) on the development of preeclampsia (PE) by targeting programmed cell death 4 (PDCD4). The primary hucMSCs were cultured and transfected with miR-342-5p, and the exosomes (Exo) were extracted from the hucMSCs. PE rats were performed with an intraperitoneal injection of L-NAME from days 11 to 19 of gestation, and injection of Exo, Exo-negative control (NC), Exo-miR-342-5p agomir, Exo-miR-342-5p antagomir, and overexpressing PDCD4 (oe-PDCD4) vector into the placenta on the 16th day of pregnancy. HE staining was utilized to observe the pathological changes in placental tissues. TUNEL staining was implemented to evaluate cell apoptosis in placental tissues. Blood pressure and 24-h urinary protein in pregnant rats were measured by a non-invasive rat tail artery blood pressure measurement and protein auto-analyzer. Expressions of miR-342-5p, PDCD4, proinflammatory cytokines (TNF-α and IL-1β), and anti-inflammatory cytokines (IL-10 and TGF-β) were detected by RT-qPCR, and PDCD4 protein expression was determined by Western blot. The interaction between miR-342-5p and PDCD4 was analyzed by luciferase activity assay. MiR-342-5p was downregulated while PDCD4 was upregulated in the placental tissues of PE rats. HucMSC-Exo relieved pathology and suppressed inflammatory response, and apoptosis in the placental tissues, as well as reducing blood pressure and 24-h urinary protein of PE rats. Elevated miR-342-5p enhanced the promoting influence of hucMSC-Exo on PE rats, while inhibited miR-342-5p reversed the functions of hucMSC-Exo on PE rats. miR-342-5p targeted PDCD4. Overexpression of PDCD4 worsened the development of PE in rats. HucMSC-Exo conveying elevated miR-342-5p inhibits the development of PE in a rat model through downregulating PDCD4.

Intra-articular injection of placental mesenchymal stromal cells ameliorates pain and cartilage anabolism/catabolism in knee osteoarthritis

Background: Knee Osteoarthritis (kOA), the most common joint degenerative disorder, lacks effective therapeutics. Placenta-derived mesenchymal stromal cells (PMSCs) are effective in tissue repairing and generation, which have potential in treating kOA. This study aimed to determine the anti-kOA efficacy of PMSCs and to explore its action mode. Methods: Flow cytometry and three-line differentiation were performed for identification of PMSCs. In vivo, a rat kOA model established by anterior cruciate ligament transection (ACLT) surgery was used to evaluate the efficacy of PMSCs. Histopathological HE and SO staining with Osteoarthritis Research Society International scoring were conducted, and cartilage expressions of MMP13 and Col2 were measured by immunohistochemistry. Pain behavior parameters by mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL), were measured. In vitro, wound healing and cell immunofluorescence assays were conducted to detect the proliferation and migration ability of chondrocytes treated with PMSCs conditioned medium (PMSCs-CM). Quantitative real-time PCR (qRT-PCR) and Western blot (WB) assays were applied to explore the molecular action of PMSCs on chondrocytes. Results: The results of flow cytometry indicated that the surface markers of PMSCs (CD73 > 95%, CD90 > 95%, and CD34 < 2%) were consistent with the typical mesenchymal stromal cells. The in vivo data showed that PMSCs significantly reversed the kOA progression by protection of cartilage, regulation of anabolic (Col2) and catabolic (MMP13) expressions, and relief of pain symptoms. The in vitro data showed that PMSCs promoted chondrocyte proliferation and migration and significantly restored the IL-1β-induced abnormal gene expressions of Col2, Mmp13, Adamts4, Adamts5 and Sox9 and also restored the abnormal protein expressions of Col2, Mmp13 and Sox9 of chondrocytes. The molecular actions of PMSCs on chondrocytes in nested co-culture way or in conditioned medium way were similar, confirming a paracrine-based mode of action. Conclusion: This study demonstrated PMSCs' anti-kOA efficacy and its paracrine-based action mode, providing novel knowledge of PMSCs and suggesting it as a promising cell therapy for treatment of kOA.

PFKFB3-mediated glycometabolism reprogramming modulates endothelial differentiation and angiogenic capacity of placenta-derived mesenchymal stem cells

BACKGROUND

Mesenchymal stem cells (MSCs) have a great potential ability for endothelial differentiation, contributing to an effective means of therapeutic angiogenesis. Placenta-derived mesenchymal stem cells (PMSCs) have gradually attracted attention, while the endothelial differentiation has not been fully evaluated in PMSCs. Metabolism homeostasis plays an important role in stem cell differentiation, but less is known about the glycometabolic reprogramming during the PMSCs endothelial differentiation. Hence, it is critical to investigate the potential role of glycometabolism reprogramming in mediating PMSCs endothelial differentiation.

METHODS

Dil-Ac-LDL uptake assay, flow cytometry, and immunofluorescence were all to verify the endothelial differentiation in PMSCs. Seahorse XF Extracellular Flux Analyzers, Mito-tracker red staining, Mitochondrial membrane potential (MMP), lactate secretion assay, and transcriptome approach were to assess the variation of mitochondrial respiration and glycolysis during the PMSCs endothelial differentiation. Glycolysis enzyme 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) was considered a potential modulator for endothelial differentiation in PMSCs by small interfering RNA. Furthermore, transwell, in vitro Matrigel tube formation, and in vivo Matrigel plug assays were performed to evaluate the effect of PFKFB3-induced glycolysis on angiogenic capacities in this process.

RESULTS

PMSCs possessed the superior potential of endothelial differentiation, in which the glycometabolic preference for glycolysis was confirmed. Moreover, PFKFB3-induced glycometabolism reprogramming could modulate the endothelial differentiation and angiogenic abilities of PMSCs.

CONCLUSIONS

Our results revealed that PFKFB3-mediated glycolysis is important for endothelial differentiation and angiogenesis in PMSCs. Our understanding of cellular glycometabolism and its regulatory effects on endothelial differentiation may propose and improve PMSCs as a putative strategy for clinical therapeutic angiogenesis.

Significance of Placental Mesenchymal Stem Cell in Placenta Development and Implications for Preeclampsia

The well-developed placentation is fundamental for the reproductive pregnancy while the defective placental development is the pathogenetic basis of preeclampsia (PE), a dangerous complication of pregnancy comprising the leading causes of maternal and perinatal morbidity and mortality. Placenta-derived mesenchymal stem cells (PMSCs) are a group of multipotent stem cells that own a potent capacity of differentiating into constitutive cells of vessel walls. Additionally, with the paracrine secretion of various factors, PMSCs inextricably link and interact with other component cells in the placenta, collectively improving the placental vasculature, uterine spiral artery remolding, and uteroplacental interface immunoregulation. Recent studies have further indicated that preeclamptic PMSCs, closely implicated in the abnormal crosstalk between other ambient cells, disturb the homeostasis and development in the placenta. Nevertheless, PMSCs transplantation or PMSCs exosome therapies tend to improve the placental vascular network and trophoblastic functions in the PE model, suggesting PMSCs may be a novel and putative therapeutic strategy for PE. Herein, we provide an overview of the multifaceted contributions of PMSCs in early placental development. Thereinto, the intensive interactions between PMSCs and other component cells in the placenta were particularly highlighted and further extended to the implications in the pathogenesis and therapeutic strategies of PE.

Human acellular amniotic membrane scaffolds encapsulating juvenile cartilage fragments accelerate the repair of rabbit osteochondral defects

Aims

The purpose of this study was to explore a simple and effective method of preparing human acellular amniotic membrane (HAAM) scaffolds, and explore the effect of HAAM scaffolds with juvenile cartilage fragments (JCFs) on osteochondral defects.

Methods

HAAM scaffolds were constructed via trypsinization from fresh human amniotic membrane (HAM). The characteristics of the HAAM scaffolds were evaluated by haematoxylin and eosin (H&E) staining, picrosirius red staining, type II collagen immunostaining, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Human amniotic mesenchymal stem cells (hAMSCs) were isolated, and stemness was verified by multilineage differentiation. Then, third-generation (P3) hAMSCs were seeded on the HAAM scaffolds, and phalloidin staining and SEM were used to detect the growth of hAMSCs on the HAAM scaffolds. Osteochondral defects (diameter: 3.5 mm; depth: 3 mm) were created in the right patellar grooves of 20 New Zealand White rabbits. The rabbits were randomly divided into four groups: the control group (n = 5), the HAAM scaffolds group (n = 5), the JCFs group (n = 5), and the HAAM + JCFs group (n = 5). Macroscopic and histological assessments of the regenerated tissue were evaluated to validate the treatment results at 12 weeks.

Results

In vitro, the HAAM scaffolds had a network structure and possessed abundant collagen. The HAAM scaffolds had good cytocompatibility, and hAMSCs grew well on the HAAM scaffolds. In vivo, the macroscopic scores of the HAAM + JCFs group were significantly higher than those of the other groups. In addition, histological assessments demonstrated that large amounts of hyaline-like cartilage formed in the osteochondral defects in the HAAM + JCFs group. Integration with surrounding normal cartilage and regeneration of subchondral bone in the HAAM + JCFs group were better than those in the other groups.

Conclusion

HAAM scaffolds combined with JCFs promote the regenerative repair of osteochondral defects.

Cite this article: Bone Joint Res 2022;11(6):349–361.

Increased phosphatase regenerating liver-1 trigger vascular remodeling in injured ovary via platelet-derived growth factor signaling pathway

Background

Vascular abnormalities in the ovary cause infertility accompanied by ovarian insufficiency due to a microenvironment of barren ovarian tissues. Placenta-derived mesenchymal stem cells (PD-MSCs, Naïve) treatment in ovarian dysfunction shows angiogenic effect, however, the therapeutic mechanism between ovarian function and vascular remodeling still unclear. Therefore, we examined whether by phosphatase regenerating liver-1 (PRL-1), which is correlated with angiogenesis in reproductive systems, overexpressed PD-MSCs could maximize the angiogenic effects in an ovarian tissues injured of rat model with partial ovariectomy and their therapeutic mechanism by enhanced vascular function via PDGF signaling.

Methods

PD-MSCs^PRL-1 (PRL-1) were generated by nonviral AMAXA gene delivery system and analyzed the vascular remodeling and follicular development in ovary. One week after Sprague–Dawley (SD) rats ovariectomy, Naïve and PRL-1 was transplanted. The animals were sacrificed at 1, 3 and 5 weeks after transplantation and vascular remodeling and follicular development were analyzed. Also, human umbilical vein endothelial cells (HUVECs) and ovarian explantation culture were performed to prove the specific effects and mechanism of PRL-1.

Results

Vascular structures in ovarian tissues (e.g., number of vessels, thickness and lumen area) showed changes in the Naïve and PRL-1-overexpressed PD-MSC (PRL-1) transplantation (Tx) groups compared to the nontransplantation (NTx) group. Especially, PRL-1 induce to increase the expression of platelet-derived growth factor (PDGF), which plays a role in vascular remodeling as well as follicular development, compared to the NTx. Also, the expression of genes related to pericyte and vascular permeability in arteries was significantly enhanced in the PRL-1 compared to the NTx (p < 0.05). PRL-1 enhanced the vascular formation and permeability of human umbilical vein endothelial cells (HUVECs) via activated the PDGF signaling pathway.

Conclusions

Our results show that PRL-1 restored ovarian function by enhanced vascular function via PDGF signaling pathway. These findings offer new insight into the effects of functionally enhanced stem cell therapy for reproductive systems and should provide new avenues to develop more efficient therapies in degenerative medicine.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02772-9.

Exosomes Immunity Strategy: A Novel Approach for Ameliorating Intervertebral Disc Degeneration

Low back pain (LBP), which is one of the most severe medical and social problems globally, has affected nearly 80% of the population worldwide, and intervertebral disc degeneration (IDD) is a common musculoskeletal disorder that happens to be the primary trigger of LBP. The pathology of IDD is based on the impaired homeostasis of catabolism and anabolism in the extracellular matrix (ECM), uncontrolled activation of immunologic cascades, dysfunction, and loss of nucleus pulposus (NP) cells in addition to dynamic cellular and biochemical alterations in the microenvironment of intervertebral disc (IVD). Currently, the main therapeutic approach regarding IDD is surgical intervention, but it could not considerably cure IDD. Exosomes, extracellular vesicles with a diameter of 30–150 nm, are secreted by various kinds of cell types like stem cells, tumor cells, immune cells, and endothelial cells; the lipid bilayer of the exosomes protects them from ribonuclease degradation and helps improve their biological efficiency in recipient cells. Increasing lines of evidence have reported the promising applications of exosomes in immunological diseases, and regarded exosomes as a potential therapeutic source for IDD. This review focuses on clarifying novel therapies based on exosomes derived from different cell sources and the essential roles of exosomes in regulating IDD, especially the immunologic strategy.

Synergistic regenerative therapy of thin endometrium by human placenta-derived mesenchymal stem cells encapsulated within hyaluronic acid hydrogels

Background

Thin endometrium is a primary cause of defective endometrial receptivity, resulting in infertility or recurrent miscarriage. Much effort has been devoted toward regenerating thin endometrium by stem cell-based therapies. The human placenta-derived mesenchymal stem cells (HP-MSCs) are emerging alternative sources of MSCs with various advantages. To maximize their retention inside the uterus, we loaded HP-MSCs with cross-linked hyaluronic acid hydrogel (HA hydrogel) to investigate their therapeutic efficacy and possible underlying mechanisms.

Methods

Ethanol was injected into the mice uterus to establish the endometrium-injured model. The retention time of HP-MSCs and HA hydrogel was detected by in vivo imaging, while the distribution of HP-MSCs was detected by immunofluorescence staining. Functional restoration of the uterus was assessed by testing embryo implantation rates. The endometrial morphological alteration was observed by H&E staining, Masson staining, and immunohistochemistry. In vitro studies were further conducted using EdU, transwell, tube formation, and western blot assays.

Results

Instilled HP-MSCs with HA hydrogel (HP-MSCs-HA) exhibited a prolonged retention time in mouse uteri than normal HP-MSCs. In vivo studies showed that the HP-MSCs-HA could significantly increase the gland number and endometrial thickness (P < 0.001, P < 0.05), decrease fibrous area (P < 0.0001), and promote the proliferation and angiogenesis of endometrial cells (as indicated by Ki67 and VEGF, P < 0.05, P < 0.05, respectively) in mice injured endometrium. HP-MSCs-HA could also significantly improve the embryo implantation rate (P < 0.01) compared with the ethanol group. Further mechanistic study showed the paracrine effects of HP-MSCs. They could not only promote the proliferation and migration of human endometrial stromal cells via the JNK/Erk1/2-Stat3-VEGF pathway but also facilitate the proliferation of glandular cells via Jak2-Stat5 and c-Fos-VEGF pathway. In turn, the increased VEGF in the endometrium promoted the angiogenesis of endothelial cells.

Conclusion

Our study suggested the potential therapeutic effects and the underlying mechanisms of HP-MSCs-HA on treating thin endometrium. HA hydrogel could be a preferable delivery method for HP-MSCs, and the strategy represents a promising therapeutic approach against endometrial injury in clinical settings.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02717-2.

The Protective Benefit of Heme Oxygenase-1 Gene-Modified Human Placenta-Derived Mesenchymal Stem Cells in a N-Nitro-L-Arginine Methyl Ester-Induced Preeclampsia-Like Rat Model: Possible Implications for Placental Angiogenesis

We previously reported that cytoprotective Heme oxygenase-1, HO-1 (HMOX1) gene-modified human placenta-derived mesenchymal stem cell (HO-1-PMSC) improved placental vascularization in vitro. In the current study, we explored the protective benefit of HO-1-PMSC transplantation in a preeclampsia (PE)-like rat model. A model of PE was successfully constructed by intraperitoneal injection of N-nitro-L-arginine methyl ester (L-NAME). Blood pressure and urinary protein levels were measured. Doppler ultrasound was examined to understand uteroplacental perfusion. ELISA was used to examine the serum levels of VEGF, PlGF, sFlt-1, and sEng. The placentas and fetuses were weighed to verify the improvement in pregnancy outcome. Immunohistochemical and H&E staining was used to detect microvessel density (MVD) in placental tissues and kidney pathology, respectively. The distribution of GFP-labeled PMSC in the placenta were observed under fluorescence microscopy. Blood pressure and proteinuria were reduced and kidney damage was improved. PE rat models treated with PMSC and HO-1-PMSC exhibited an increase in the quality of fetuses and placentas, MVD, VEGF, and PlGF expression, but substantially decreased expression of sFlt-1 and sEng. Doppler ultrasound showed that the placental perfusion was improved. Green fluorescent tracing experiments verified that the cells were successfully transplanted into the placenta and distributed in the blood vessels, indicating that the cells might participate in the process of angiogenesis. These results indicate that therapy with HO-1-PMSC could improve placental vascular dysplasia, increase placental perfusion, control PE symptoms, and promote pregnancy outcome by regulating the balance of angiogenic and antiangiogenic factors or directly participating in the repair of placental vessels in a PE-like rat model.

Conditioned medium from primary cytotrophoblasts, primary placenta-derived mesenchymal stem cells, or sub-cultured placental tissue promoted HUVEC angiogenesis in vitro

Background

As a large capillary network, the human placenta plays an important role throughout pregnancy. Placental vascular development is complex and delicate and involves many types of placental cells, such as trophoblasts, and mesenchymal stem cells. There has been no systematic, comparative study on the roles of these two groups of placental cells and the whole placental tissue in the placental angiogenesis. In this study, primary cytotrophoblasts (CTBs) from early pregnancy and primary human placenta-derived mesenchymal stem cells (hPDMSCs) from different stages of pregnancy were selected as the cell research objects, and full-term placental tissue was selected as the tissue research object to detect the effects of their conditioned medium (CM) on human umbilical vein endothelial cell (HUVEC) angiogenesis.

Methods

We successfully isolated primary hPDMSCs and CTBs, collected CM from these placental cells and sub-cultured placental tissue, and then evaluated the effects of the CM on a series of angiogenic processes in HUVECs in vitro. Furthermore, we measured the levels of angiogenic factors in the CM of placental cells or tissue by an angiogenesis antibody array.

Results

The results showed that not only placental cells but also sub-cultured placental tissue, to some extent, promoted HUVEC angiogenesis in vitro by promoting proliferation, adhesion, migration, invasion, and tube formation. We also found that primary placental cells in early pregnancy, whether CTBs or hPDMSCs, played more significant roles than those in full-term pregnancy. Placental cell-derived CM collected at 24 h or 48 h had the best effect, and sub-cultured placental tissue-derived CM collected at 7 days had the best effect among all the different time points. The semiquantitative angiogenesis antibody array showed that 18 of the 43 angiogenic factors had obvious spots in placental cell-derived CM or sub-cultured placental tissue-derived CM, and the levels of 5 factors (including CXCL-5, GRO, IL-6, IL-8, and MCP-1) were the highest in sub-cultured placental tissue-derived CM.

Conclusions

CM obtained from placental cells (primary CTBs or hPDMSCs) or sub-cultured placental tissue contained proangiogenic factors and promoted HUVEC angiogenesis in vitro. Therefore, our research is helpful to better understand placental angiogenesis regulation and provides theoretical support for the clinical application of placental components, especially sub-cultured placental tissue-derived CM, in vascular tissue engineering and clinical treatments.

Placental multipotent mesenchymal stromal cell-derived Slit2 may regulate macrophage motility during placental infection

Slit proteins have been reported to act as axonal repellents in Drosophila; however, their role in the placental microenvironment has not been explored. In this study, we found that human placental multipotent mesenchymal stromal cells (hPMSCs) constitutively express Slit2. Therefore, we hypothesized that Slit2 expressed by hPMSCs could be involved in macrophage migration during placental inflammation through membrane cognate Roundabout (Robo) receptor signaling. In order to develop a preclinical in vitro mouse model of hPMSCs in treatment of perinatal infection, RAW 264.7 cells were used in this study. Slit2 interacted with Robo4 that was highly expressed in RAW 264.7 macrophages: their interaction increased the adhesive ability of RAW 264.7 cells and inhibited migration. Lipopolysaccharide (LPS)-induced CD11bCD18 expression could be inhibited by Slit2 and by hPMSC-conditioned medium (CM). LPS-induced activation of p38 and Rap1 was also attenuated by Slit2 and by hPMSC-CM. Noticeably, these inhibitory effects of hPMSC-CM decreased after depletion of Slit2 from the CM. Furthermore, we found that p38 siRNA inhibited LPS-induced Rap1 expression in RAW 264.7 cells, indicating that Rap1 functions downstream of p38 signaling. p38 siRNA increased cell adhesion and inhibited migration through reducing LPS-stimulated CD11bCD18 expression in RAW 264.7 cells. Thus, hPMSC-derived Slit2 may inhibit LPS-induced CD11bCD18 expression to decrease cell migration and increase adhesion through modulating the activity and motility of inflammatory macrophages in placenta. This may represent a novel mechanism for LPS-induced placental infection.

The role of β-HCG and VEGF-MEK/ERK signaling pathway in villi angiogenesis in patients with missed abortion

OBJECTIVE

To analyze the effects of the Human Chorionic Gonadotropin beta (β-hCG) and the VEGF-MEK/ERK signaling pathway on villi angiogenesis in early missed abortion.

METHODS

A total of 12 cases of women with missed abortion and 12 cases of women who had induced abortion voluntarily without any disease were included in the present study. The age, pregnancy time and gestation period in the control group corresponded to the missed abortion group. Wes Simple Western system and qRT-PCR were used to detect the expression of VEGF-MEK/ERK signaling pathway related proteins and genes in villous. Radioimmunoassay and Enzyme-linked immunosorbent assay were used to detect β-hCG and VEGF levels in serum. The microvascular density (MVD) in villous tissue was analyzed by immunohistochemical staining.

RESULTS

The levels of β-hCG and VEGF in serum, the expression of VEGF-MEK/ERK signaling pathway and MVD in villous tissue of the missed abortion group were lower than those of the control group. In addition, compared with the control group, the layers of trophoblasts of the villous tissue in the missed abortion group became thinner significantly, the number of cells reduced, the cell structures were disorganized, and parts of the trophoblast cells were absent. Correlational analysis showed that the protein expression of ERK1/2 was positively correlated with MVD in missed abortion group.

CONCLUSIONS

Our results reveal that decreased production of β-hCG in early pregnant women could down-regulate the expression of VEGF-MEK/ERK signal pathway, then reduce angiogenesis and eventually leading to the abnormal angiogenesis of villous, which may be an important mechanism of missed abortion.

Mesenchymal Stem Cells Decrease M1/M2 Ratio and Alleviate Inflammation to Improve Limb Ischemia in Mice

BACKGROUND Limb ischemia (LI) is the underlying pathology of peripheral artery disease (PAD). Macrophages play a critical role in inflammation and can contribute to the exacerbation or reduction of inflammation. Transplantation of mesenchymal stem cells (MSCs) is an emerging therapeutic strategy for PAD. However, the mechanism by which human placenta-derived mesenchymal stem cells (PMSCs) regulate macrophage differentiation in ischemic tissue remains unclear. MATERIAL AND METHODS Placentas were obtained from healthy donors with normal 38- to 40-week gestation, and PMSCs were isolated from the placentas and cultured. A mouse model of hind-limb ischemia was established. Ischemic limbs were injected intramuscularly with about 5×10⁶ PMSCs in the PMSCs group or a placebo solution (phosphate-buffered saline) in the control group at 4 different sites 1 day after the procedure. The blood perfusion of hind-limbs and the histological morphology were observed at day 1, 7, and 14 after the surgical procedure. Macrophages were detected by flow cytometry. The expression of serum tumor necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, and IL-10 were detected by enzyme-linked immunosorbent assay (ELISA). The expression of CD31 and smooth muscle alpha-actin (alpha-SMA) in frozen muscle samples were detected by immunofluorescence staining. RESULTS In the PMSCs group, blood perfusion was gradually recovered and ischemic injury was markedly alleviated. The percentage of M2-like macrophages was increased dramatically, while the M1/M2 macrophage ratio was reduced. The expression of TNF-alpha and IL-6 was reduced, while the IL-10 level was elevated. The expression and density of CD31- and alpha-SMA-positive vessels were both significantly increased. CONCLUSIONS Transplanted PMSCs alleviated inflammation, promoted neovascularization, and improved hind limb ischemia through regulating macrophage differentiation toward the M2 phenotype and cytokine secretion. Cytokine manipulation of macrophage phenotypes may have potential therapeutic benefits in injured ischemic limbs.

Heme oxygenase-1 gene modified human placental mesenchymal stem cells promote placental angiogenesis and spiral artery remodeling by improving the balance of angiogenic factors in vitro

INTRODUCTION

Abnormal placental vascular development is a possible cause of preeclampsia. Mesenchymal stem cell (MSC)-based therapy is a promising approach for tissue repair and angiogenesis. Further, heme oxygenase-1 (HO-1) has beneficial effects on the angiogenic balance during pregnancy. We explored the effects of HO-1 overexpression on placental vascularization using human placenta-derived MSCs (hPMSCs).

METHODS

hPMSCs were isolated from term placenta, and the HO-1 gene was transfected with a lentivirus. Proliferation, migration, and apoptosis of hPMSCs and HO-hPMSCs were examined using CCK8 assay, trans-well assay, and flow cytometry, respectively. Paracrine secretion of the angiogenesis factors VEGF and PlGF, as well as the anti-angiogenesis factors sFlt-1 and sEng, from hPMSC/HO-hPMSCs was measured by qRT-PCR and ELISA. Human umbilical cord endothelial cells and a villus-decidua co-culture were treated with conditioned media to study the effect of HO-1-hPMSCs on tube formation and villus vascular remodeling.

RESULTS

HO-1 significantly improved the proliferation and migration of hPMSCs. Additionally, HO-1 reduced hPMSCs apoptosis. The levels of VEGF were increased in HO-1-hPMSCs, whereas those of sFlt-1 decreased. Tube formation assays showed that the conditioned media from HO-1-hPMSCs resulted in more branching points than those from the controls. The villus-decidua co-culture system confirmed that HO-1-hPMSCs are conducive to angiogenesis and vascular remodeling.

DISCUSSION

HO-1-modified hPMSCs improve placental vascularization by promoting a balance of pro- and anti- angiogenesis factors, which is worthy of further study as an alternative treatment for preeclampsia.

Three-dimensional silk fibroin scaffolds enhance the bone formation and angiogenic differentiation of human amniotic mesenchymal stem cells: a biocompatibility analysis

Silk fibroin (SF) is a fibrous protein with unique mechanical properties, adjustable biodegradation, and the potential to drive differentiation of mesenchymal stem cells (MSCs) along the osteogenic lineage, making SF a promising scaffold material for bone tissue engineering. In this study, hAMSCs were isolated by enzyme digestion and identified by multiple-lineage differentiation. SF scaffold was fabricated by freeze-drying, and the adhesion and proliferation abilities of hAMSCs on scaffolds were determined. Osteoblast differentiation and angiogenesis of hAMSCs on scaffolds were further evaluated, and histological staining of calvarial defects was performed to examine the cocultured scaffolds. We found that hAMSCs expressed the basic surface markers of MSCs. Collagen type I (COL-I) expression was observed on scaffolds cocultured with hAMSCs. The scaffolds potentiated the proliferation of hAMSCs and increased the expression of COL-I in hAMSCs. The scaffolds also enhanced the alkaline phosphatase activity and bone mineralization, and upregulated the expressions of osteogenic-related factors in vitro. The scaffolds also enhanced the angiogenic differentiation of hAMSCs. The cocultured scaffolds increased bone formation in treating critical calvarial defects in mice. This study first demonstrated that the application of 3D SF scaffolds co-cultured with hAMSCs greatly enhanced osteogenic differentiation and angiogenesis of hAMSCs in vitro and in vivo. Thus, 3D SF scaffolds cocultured with hAMSCs may be a better alternative for bone tissue engineering.

Schnurri-3 regulates BMP9-induced osteogenic differentiation and angiogenesis of human amniotic mesenchymal stem cells through Runx2 and VEGF

Human amniotic mesenchymal stem cells (hAMSCs) are multiple potent progenitor cells (MPCs) that can differentiate into different lineages (osteogenic, chondrogenic, and adipogenic cells) and have a favorable capacity for angiogenesis. Schnurri-3 (Shn3) is a large zinc finger protein related to Drosophila Shn, which is a critical mediator of postnatal bone formation. Bone morphogenetic protein 9 (BMP9), one of the most potent osteogenic BMPs, can strongly upregulate various osteogenesis- and angiogenesis-related factors in MSCs. It remains unclear how Shn3 is involved in BMP9-induced osteogenic differentiation coupled with angiogenesis in hAMSCs. In this investigation, we conducted a comprehensive study to identify the effect of Shn3 on BMP9-induced osteogenic differentiation and angiogenesis in hAMSCs and analyze the responsible signaling pathway. The results from in vitro and in vivo experimentation show that Shn3 notably inhibits BMP9-induced early and late osteogenic differentiation of hAMSCs, expression of osteogenesis-related factors, and subcutaneous ectopic bone formation from hAMSCs in nude mice. Shn3 also inhibited BMP9-induced angiogenic differentiation, expression of angiogenesis-related factors, and subcutaneous vascular invasion in mice. Mechanistically, we found that Shn3 prominently inhibited the expression of BMP9 and activation of the BMP/Smad and BMP/MAPK signaling pathways. In addition, we further found activity on runt-related transcription factor 2 (Runx2), vascular endothelial growth factor (VEGF), and the target genes shared by BMP and Shn3 signaling pathways. Silencing Shn3 could dramatically enhance the expression of Runx2, which directly regulates the downstream target VEGF to couple osteogenic differentiation with angiogenesis. To summarize, our findings suggested that Shn3 significantly inhibited the BMP9-induced osteogenic differentiation and angiogenesis in hAMSCs. The effect of Shn3 was primarily seen through inhibition of the BMP/Smad signaling pathway and depressed expression of Runx2, which directly regulates VEGF, which couples BMP9-induced osteogenic differentiation with angiogenesis.

Placental mesenchymal stromal cells as an alternative tool for therapeutic angiogenesis

Dysregulation of angiogenesis is a phenomenon observed in several disorders such as diabetic foot, critical limb ischemia and myocardial infarction. Mesenchymal stromal cells (MSCs) possess angiogenic potential and have recently emerged as a powerful tool for cell therapy to promote angiogenesis. Although bone marrow-derived MSCs are the primary cell of choice, obtaining them has become a challenge. The placenta has become a popular alternative as it is a highly vascular organ, easily available and ethically more favorable with a rich supply of MSCs. Comparatively, placenta-derived MSCs (PMSCs) are clinically promising due to their proliferative, migratory, clonogenic and immunomodulatory properties. PMSCs release a plethora of cytokines and chemokines key to angiogenic signaling and facilitate the possibility of delivering PMSC-derived exosomes as a targeted therapy to promote angiogenesis. However, there still remains the challenge of heterogeneity in the isolated populations, questions on the maternal or fetal origin of these cells and the diversity in previously reported isolation and culture conditions. Nonetheless, the growing rate of clinical trials using PMSCs clearly indicates a shift in favor of PMSCs. The overall aim of the review is to highlight the importance of this rather poorly understood cell type and emphasize the need for further investigations into their angiogenic potential as an alternative source for therapeutic angiogenesis.

A pilot study of first-line olaratumab, doxorubicin and ifosfamide in patients with metastatic soft tissue sarcoma

INTRODUCTION

Olaratumab (O) is a monoclonal antibody that specifically binds PDGFRα. The addition of O to doxorubicin (D) has been approved by the regulatory authorities for metastatic soft tissue sarcoma (MSTS). Since the combination of D + ifosfamide (I) is commonly used in MSTS and is associated with a higher response rate than D alone, it seems reasonable to combine O with the combination of D + I (ODI). We report our preliminary experience with O + D+I in MSTS.

METHODS

Between 01/01/2015 and 30/05/2018, 15 patients (pts) with MSTS were treated with ODI as first-line therapy. The treatment protocol consisted of IV D 50 mg/m² and I 5000 mg/m², day 1 (3 pts), or D 37.5 mg/m² and I 3000 mg/m² days 1-2 (12 pts). O (15 mg/kg) was given IV on days 1, 8, and cycles were repeated every 21 days.

RESULTS

With a median follow up of 16 months, 63 cycles of ODI were given. Objective response was achieved in 4 pts (27%) (CR in 3, PR in 1); 5 pts (33%) remained with stable disease for ≥ 5 mo. Median overall survival was 22 months. Major hematological toxicities (grade 3-4) included: neutropenia-7 pts (47%), and neutropenic fever-3 pts (20%). Non-hematological toxicities included grade 3 diarrheas in 2 pts (13%) after the second cycle. There was no treatment-related mortality.

CONCLUSION

According to our preliminary experience, adding olaratumab to doxorubicin and ifosfamide is active and its safety profile is comparable to that of doxorubicin and ifosfamide alone in MSTS.

Randomized phase II study of the PDGFRα antibody olaratumab plus liposomal doxorubicin versus liposomal doxorubicin alone in patients with platinum-refractory or platinum-resistant advanced ovarian cancer

BACKGROUND

Olaratumab is a platelet-derived growth factor receptor-α (PDGFRα)-targeting monoclonal antibody blocking PDGFRα signaling. PDGFRα expression is associated with a more aggressive phenotype and poor ovarian cancer outcomes. This randomized, open label phase II study evaluated olaratumab plus liposomal doxorubicin compared with liposomal doxorubicin alone in advanced ovarian cancer patients.

METHODS

Patients with platinum-refractory or platinum-resistant advanced ovarian cancer were randomized 1:1 to receive liposomal doxorubicin (40 mg/m², intravenous infusion) administered every 4 weeks with or without olaratumab (20 mg/kg, IV infusion) every 2 weeks. Patients were stratified based on prior response to platinum therapy (refractory vs resistant). The primary efficacy endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate, duration of response, and safety.

RESULTS

A total of 123 patients were treated (62 olaratumab+liposomal doxorubicin; 61 liposomal doxorubicin). Median PFS was 4.2 months for olaratumab+liposomal doxorubicin and 4.0 months for liposomal doxorubicin (stratified hazard ratio [HR] = 1.043; 95% confidence interval [CI] 0.698-1.558; p = 0.837). Median OS was 16.6 months and 16.2 months in the olaratumab+liposomal doxorubicin and liposomal doxorubicin arms, respectively (HR = 1.098; 95% CI 0.71-1.71). In the platinum-refractory subgroup, median PFS was 5.5 months (95% CI 1.6-9.2) and 3.7 months (95% CI 1.9-9.2) in the olaratumab+liposomal doxorubicin (n = 15) and liposomal doxorubicin arms (n = 16), respectively (HR = 0.85; 95% CI 0.38-1.91). Overall, 59.7% (olaratumab+liposomal doxorubicin) and 65.6% (liposomal doxorubicin) of patients reported grade ≥ 3 adverse events regardless of causality. The most common treatment-emergent adverse events (all grades) regardless of causality were fatigue related (61%), nausea (57%), and constipation (52%) with olaratumab+liposomal doxorubicin and nausea (64%), fatigue related (62%), and mucositis (46%) with liposomal doxorubicin.

CONCLUSIONS

The addition of olaratumab to liposomal doxorubicin did not result in significant prolongation of PFS or OS in platinum-resistant or platinum-refractory ovarian cancer.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00913835 ; registered June 2, 2009.

Early missed abortion is associated with villous angiogenesis via the HIF-1α/VEGF signaling pathway

Purpose

To analyze the effects of the hypoxia-inducible factor 1-alpha (HIF-1α)/vascular endothelial growth factor (VEGF) signaling pathway on villous angiogenesis in early missed abortion.

Methods

Immunohistochemical assays were performed to detect the expression of micro-vessel density (MVD), HIF-1α, and VEGF in villous tissue samples from 30 missed abortions and 30 elective abortions in early pregnancy. We further analyzed the correlation between HIF-1α/VEGF and MVD. HTR8/SVneo cells were cultured under hypoxic (1%) or normoxic (20%) conditions, tube formation was investigated, and protein and mRNA level of HIF-1α/VEGF were determined using western blot and qRT-PCR. Finally, HIF-1α was knocked down with siRNA introduced into HTR8/SVneo cell line under hypoxia, and HIF-1α/VEGF expression and HTR8/SVneo tube formation were investigated.

Results

The expression of HIF-1α, VEGF, and MVD was lower in the missed abortion than in the elective abortion group. Correlational analysis showed that the expression of HIF-1α and VEGF was positively correlated with MVD in both groups. The levels of HIF-1α/VEGF mRNA and protein in HTR8/SVneo cells were significantly enhanced under hypoxia. HIF-1α knockdown with siRNA inhibited HIF-1α/VEGF mRNA and protein levels of HTR8/SVneo cells induced by hypoxia. Tube formation of HTR8/SVneo cells was significantly enhanced in hypoxic culture and was inhibited by HIF-1α knockdown with siRNA.

Conclusions

Our results reveal a novel role for HIF-1α/VEGF in regulating villous angiogenesis in early pregnancy and suggest that it may be a novel biomarker for missed abortion.

Platelet-derived growth factor receptor-α and -β promote cancer stem cell phenotypes in sarcomas

Sarcomas are malignant tumors derived from mesenchymal tissues and may harbor a subset of cells with cancer stem-like cell (CSC) properties. Platelet-derived growth factor receptors α and β (PDGFR-α/β) play an important role in the maintenance of mesenchymal stem cells. Here we examine the role of PDGFR-α/β in sarcoma CSCs. PDGFR-α/β activity and the effects of PDGFR-α/β inhibition were examined in 3 human sarcoma cell lines using in vitro assays and mouse xenograft models. In all three cell lines, PDGFR-α/β activity was significantly higher in cells grown as spheroids (to enrich for CSCs) and in cells sorted for CD133 expression (a marker of sarcoma CSCs). Self-renewal transcription factors Nanog, Oct4, and Slug and epithelial-to-mesenchymal transition (EMT) proteins Snail, Slug, and Zeb1 were also significantly higher in spheroids cells and CD133(+) cells. Spheroid cells and CD133(+) cells demonstrated 2.9- to 4.2-fold greater migration and invasion and resistance to doxorubicin chemotherapy. Inhibition of PDGFR-α/β in CSCs using shRNA or pharmacologic inhibitors reduced expression of certain self-renewal and EMT proteins, reduced spheroid formation by 74-82%, reduced migration and invasion by 73-80%, and reversed chemotherapy resistance. In mouse xenograft models, combining PDGFR-α/β inhibition (using shRNA or imatinib) with doxorubicin had a more-than-additive effect in blocking tumor growth, with enhanced apoptosis, especially in CD133(+) cells. These results indicate that PDGFR-α/β activity is upregulated in sarcoma CSCs and promote CSC phenotypes including migration, invasion, and chemotherapy resistance. Thus, the PDGFR-α/β pathway represents a new potential therapeutic target to reduce metastatic potential and increase chemosensitivity.

Conditioned Medium from Human Umbilical Vein Endothelial Cells Promotes Proliferation, Migration, Invasion and Angiogenesis of Adipose Derived Stem Cells

Preeclampsia (PE) is a pregnancy-specific hypertensive complication, closely related to endothelial dysfunction. Adipose derived stem cells (ADSCs) have the capacity to differentiate into endothelial cells for vascular repair. Therefore, we hypothesized that induced endothelial differentiation of ADSCs might hold great potential for the treatment of PE. In this study, the primary ADSCs and human umbilical vein endothelial cells (HUVECs) were isolated by the collagenase digestion method. The supernatant of HUVECs was collected from the first generation of cells. Then, ADSCs were divided into two groups: ADSCs alone group and induced ADSCs (iADSCs) group. In iADSCs group, ADSCs were induced by HUVECs conditioned medium and ADSCs special culture medium at a ratio of 1:1 over a two-week period. In order to identify the endothelial characteristics of iADSCs, CD31 and CD34 were examined by flow cytometry. The proliferation, migration, invasion and angiogenesis assays were employed to compare the bioactivity of iADSCs and ADSCs. Furthermore, The levels of angiogenic related factors including vascular endothelial growth factor (VEGF) and placenta growth factor (P1GF) were detected by RT-PCR and Western blotting. Results showed conditioned medium from HUVECs promoted ADSCs proliferation, migration, invasion and angiogenesis. In addition, the levels of VEGF and P1GF were significantly enhanced in iADSCs group. This study uncovered the iADSCs application potential in the therapy and intervention of PE.

Detection of bovine Deltapapillomavirus DNA in peripheral blood of healthy sheep (Ovis aries)

Blood samples from 65 sheep were tested for the presence of bovine Deltapapillomavirus (δPVs) DNA. The sheep were divided into three groups. Sheep in groups 1 and 2 were from Sardinia and Campania, respectively, and were in contact with cattle and grazed on lands contaminated with bracken fern. Sheep in Group 3 lived in closed pens and had no contact with cattle. These sheep were fed hay that did not contain bracken fern. Bovine δPV E5 DNA was detected in blood from 24 of 27 (89%) sheep in Group 1. A single bovine δPV type was detected in the blood from nine (33%) sheep, including the detection of bovine δPV-1 DNA in four sheep, bovine δPV-2 in four and δPV-13 in one sheep. Two δPV types were detected in 33% of the sheep, and three bovine δPV types were detected in 22% of the sheep. Bovine δPVs were detected in 17 of 20 (85%) sheep from Group 2. The detection rate by a single δPV type was 40% with just δPV-1 DNA amplified from two, just δPV-2 DNA from four, and just δPV-13 DNA from two sheep. Two and three δPVs were detected in 30% and 15%, respectively. All sequenced amplicons showed a 100% identity with papillomaviral E5 DNA deposited in GenBank. Bovine δPV-14 DNA sequences were not detected from any sheep. No bovine δPV DNA was revealed in blood samples from sheep in Group 3. The detection of bovine δPV DNA in the blood of sheep means that sheep may be able to be infected by these PVs. This suggests that bovine δPVs could potentially be a previously unrecognized cause of disease in sheep. Furthermore, it is possible that sheep could act as a reservoir for these viruses.

Evaluation of circulating miRNAs during late pregnancy in the mare

MicroRNAs (miRNAs) are small, non-coding RNAs which are produced throughout the body. Individual tissues tend to have a specific expression profile and excrete many of these miRNAs into circulation. These circulating miRNAs may be diagnostically valuable biomarkers for assessing the presence of disease while minimizing invasive testing. In women, numerous circulating miRNAs have been identified which change significantly during pregnancy-related complications (e.g. chorioamnionitis, eclampsia, recurrent pregnancy loss); however, no prior work has been done in this area in the horse. To identify pregnancy-specific miRNAs, we collected serial whole blood samples in pregnant mares at 8, 9, 10 m of gestation and post-partum, as well as from non-pregnant (diestrous) mares. In total, we evaluated a panel of 178 miRNAs using qPCR, eventually identifying five miRNAs of interest. One miRNA (miR-374b) was differentially regulated through late gestation and four miRNAs (miR-454, miR-133b, miR-486-5p and miR-204b) were differentially regulated between the pregnant and non-pregnant samples. We were able to identify putative targets for the differentially regulated miRNAs using two separate target prediction programs, miRDB and Ingenuity Pathway Analysis. The targets for the miRNAs differentially regulated during pregnancy were predicted to be involved in signaling pathways such as the STAT3 pathway and PI3/AKT signaling pathway, as well as more endocrine-based pathways, including the GnRH, prolactin and insulin signaling pathways. In summary, this study provides novel information about the changes occurring in circulating miRNAs during normal pregnancy, as well as attempting to predict the biological effects induced by these miRNAs.

Plasma miRNA Profiles in Pregnant Women Predict Infant Outcomes following Prenatal Alcohol Exposure

Fetal alcohol spectrum disorders (FASD) are difficult to diagnose since many heavily exposed infants, at risk for intellectual disability, do not exhibit craniofacial dysmorphology or growth deficits. Consequently, there is a need for biomarkers that predict disability. In both animal models and human studies, alcohol exposure during pregnancy resulted in significant alterations in circulating microRNAs (miRNAs) in maternal blood. In the current study, we asked if changes in plasma miRNAs in alcohol-exposed pregnant mothers, either alone or in conjunction with other clinical variables, could predict infant outcomes. Sixty-eight pregnant women at two perinatal care clinics in western Ukraine were recruited into the study. Detailed health and alcohol consumption histories, and 2^nd and 3^rd trimester blood samples were obtained. Birth cohort infants were assessed by a geneticist and classified as unexposed (UE), heavily prenatally exposed and affected (HEa) or heavily exposed but apparently unaffected (HEua). MiRNAs were assessed in plasma samples using qRT-PCR arrays. ANOVA models identified 11 miRNAs that were all significantly elevated in maternal plasma from the HEa group relative to HEua and UE groups. In a random forest analysis classification model, a combination of high variance miRNAs, smoking history and socioeconomic status classified membership in HEa and UE groups, with a misclassification rate of 13%. The RFA model also classified 17% of the HEua group as UE-like, whereas 83% were HEa-like, at least at one stage of pregnancy. Collectively our data indicate that maternal plasma miRNAs predict infant outcomes, and may be useful to classify difficult-to-diagnose FASD subpopulations.

Olaratumab and doxorubicin versus doxorubicin alone for treatment of soft-tissue sarcoma: an open-label phase 1b and randomised phase 2 trial

BACKGROUND

Treatment with doxorubicin is a present standard of care for patients with metastatic soft-tissue sarcoma and median overall survival for those treated is 12-16 months, but few, if any, novel treatments or chemotherapy combinations have been able to improve these poor outcomes. Olaratumab is a human antiplatelet-derived growth factor receptor α monoclonal antibody that has antitumour activity in human sarcoma xenografts. We aimed to assess the efficacy of olaratumab plus doxorubicin in patients with advanced or metastatic soft-tissue sarcoma.

METHODS

We did an open-label phase 1b and randomised phase 2 study of doxorubicin plus olaratumab treatment in patients with unresectable or metastatic soft-tissue sarcoma at 16 clinical sites in the USA. For both the phase 1b and phase 2 parts of the study, eligible patients were aged 18 years or older and had a histologically confirmed diagnosis of locally advanced or metastatic soft-tissue sarcoma not previously treated with an anthracycline, an Eastern Cooperative Oncology Group (ECOG) performance status of 0-2, and available tumour tissue to determine PDGFRα expression by immunohistochemistry. In the phase 2 part of the study, patients were randomly assigned in a 1:1 ratio to receive either olaratumab (15 mg/kg) intravenously on day 1 and day 8 plus doxorubicin (75 mg/m(2)) or doxorubicin alone (75 mg/m(2)) on day 1 of each 21-day cycle for up to eight cycles. Randomisation was dynamic and used the minimisation randomisation technique. The phase 1b primary endpoint was safety and the phase 2 primary endpoint was progression-free survival using a two-sided α level of 0.2 and statistical power of 0.8. This study was registered with ClinicalTrials.gov, number NCT01185964.

FINDINGS

15 patients were enrolled and treated with olaratumab plus doxorubicin in the phase 1b study, and 133 patients were randomised (66 to olaratumab plus doxorubicin; 67 to doxorubicin alone) in the phase 2 trial, 129 (97%) of whom received at least one dose of study treatment (64 received olaratumab plus doxorubicin, 65 received doxorubicin). Median progression-free survival in phase 2 was 6.6 months (95% CI 4.1-8.3) with olaratumab plus doxorubicin and 4.1 months (2.8-5.4) with doxorubicin (stratified hazard ratio [HR] 0.67; 0.44-1.02, p=0.0615). Median overall survival was 26.5 months (20.9-31.7) with olaratumab plus doxorubicin and 14.7 months (9.2-17.1) with doxorubicin (stratified HR 0.46, 0.30-0.71, p=0.0003). The objective response rate was 18.2% (9.8-29.6) with olaratumab plus doxorubicin and 11.9% (5.3-22.2) with doxorubicin (p=0.3421). Steady state olaratumab serum concentrations were reached during cycle 3 with mean maximum and trough concentrations ranging from 419 μg/mL (geometric coefficient of variation in percentage [CV%] 26.2) to 487 μg/mL (CV% 33.0) and from 123 μg/mL (CV% 31.2) to 156 μg/mL (CV% 38.0), respectively. Adverse events that were more frequent with olaratumab plus doxorubicin versus doxorubicin alone included neutropenia (37 [58%] vs 23 [35%]), mucositis (34 [53%] vs 23 [35%]), nausea (47 [73%] vs 34 [52%]), vomiting (29 [45%] vs 12 [18%]), and diarrhoea (22 [34%] vs 15 [23%]). Febrile neutropenia of grade 3 or higher was similar in both groups (olaratumab plus doxorubicin: eight [13%] of 64 patients vs doxorubicin: nine [14%] of 65 patients).

INTERPRETATION

This study of olaratumab with doxorubicin in patients with advanced soft-tissue sarcoma met its predefined primary endpoint for progression-free survival and achieved a highly significant improvement of 11.8 months in median overall survival, suggesting a potential shift in the treatment of soft-tissue sarcoma.

FUNDING

Eli Lilly and Company.

Irisin reverses platelet derived growth factor-BB-induced vascular smooth muscle cells phenotype modulation through STAT3 signaling pathway

Vascular smooth muscle cells (VSMCs) phenotype modulation toward a synthetic phenotype is the main cause of cardiovascular disease. As a newly discovered myokine, Irisin is thought to be a promising candidate for the treatment of metabolic disturbances, as well as cardiovascular disease. However, no evidence has been shown for the direct effect of Irisin on VSMCs phenotype modulation and its underling mechanisms. The aim of this study was to explore the effect of Irisin on VSMCs phenotype modulation and the mechanisms involved. In the present study, it was found that Irisin restored the PDGF-BB-induced VSMCs phenotype modulation which exhibited down-regulation of smooth muscle cells (SMC) expression and up-regulation of matrix synthesis related marker expression, as well as proliferative phenotype. Moreover, our research demonstrated that Irisin further activated STAT3 signaling pathways. Finally, by applying an STAT3 inhibitor, WP1066, we revealed the roles of STAT3 in the PDGF-BB-induced VSMCs phenotype modulation when they were treated with Irisin. Taken together, these results demonstrated that Irisin may play a crucial role in regulating VSMCs phenotype modulation via the STAT3 signaling pathway.

The effect of bisphosphonates on the endothelial differentiation of mesenchymal stem cells

The contribution of the local stem cell niche to providing an adequate vascular framework during healing cannot be overemphasized. Bisphosphonates (BPs) are known to have a direct effect on the local vasculature, but their effect on progenitor cell differentiation is unknown. This in vitro study evaluated the effect(s) of various BPs on the differentiation of human placental mesenchymal stem cells (pMSCs) along the endothelial lineage and their subsequent functional and morphogenic capabilities. pMSC multipotency was confirmed by successful differentiation into cells of both the osteogenic and endothelial lineages, as demonstrated by positive Alizarin Red S staining and Ac-LDL uptake. pMSC differentiation in the presence of non-cytotoxic BP concentrations showed that nitrogen containing BPs had a significant inhibitory effect on cell migration and endothelial marker gene expression, as well as compromised endothelial differentiation as demonstrated using von Willebrand factor immunofluorescence staining and tube formation assay. This in vitro study demonstrated that at non-cytotoxic levels, nitrogen-containing BPs inhibit differentiation of pMSCs into cells of an endothelial lineage and affect the downstream functional capability of these cells supporting a multi-modal effect of BPs on angiogenesis as pathogenic mechanism contributing to bone healing disorders such as bisphosphonate related osteonecrosis of the jaws (BRONJ).