PDGF-B Expression Research Articles

PDGFR-β As a New Therapeutic Target in T-Cell Acute Lymphoblastic Leukemia

T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy that accounts for 10-15% of pediatric and 25% of adult ALL cases. General prognosis of T-ALL has been improving over time. However, the outcome of T-ALL patients with primary resistant or relapsed leukemia remains dismal. PDGFR-β is a transmembrane glycoprotein dimer molecule that functions as a receptor tyrosine kinase. Ligand binding (PDGF-B/PDGF-D) results in receptor dimerization and subsequent activation via autophosphorylation, causing the downstream activation of various signaling pathways such as PI3K/AKT, MAPK/ERK, JAK/STAT and Notch. During normal T cell development, PDGFR-β is expressed in the double negative stage in CD34+ T-cells and drops dramatically once CD34 is lost. The expression of both ligands, PDGF-B and PDGF-D, seems to be restricted to γδ CD3+ CD1- T-cells. We looked in vivo to the effect of PDGFR-β overexpression on normal T cell development making use of CD2-iCre driven overexpression of PDGFR- β in a C57Bl6 background. Overexpression of PDGFR-β in the R26-locus did not affect normal T-cell development. In T-ALL patients, high PDGFR-β expression can be observed in the HOXA and TLX3 subgroups. These subgroups have significantly higher PDGFR-β expression compared to normal developing T-cells. As constitutively active PDGFR-β is observed in a variety of malignancies, multi-target kinase inhibitors are already used in the clinic. However, they are not specific and often result in adverse side-effects. CP-673451 is a novel, potent and selective PDGFR inhibitor. Mechanistically, CP-673451 inhibits autophosphorylation of dimeric PDGFR-β and in this way prevents phosphorylation of downstream PI3K/AKT, GSK-3α and GSK-3β. Previous studies showed growth inhibition of multiple tumor xenografts (lung and colon carcinomas, glioblastoma) mainly due to a direct antitumor effect. Previously, we demonstrated the efficacy of CP-673451 on a T-ALL (IC50=544 nM) and a B-ALL cell line (IC50=500nM) with high PDGFR-β expression, as well as on a T-ALL PDX model with high levels of PDGFR-β (IC50=1,6 nM). Both cell lines and PDX models showed phosphorylation of the PDGFR-β receptor. After PDGFR-β inhibition, a decrease of PDGFR-β could be observed as a negative feedback loop. Also, phosphorylation of the receptor itself decreased which resulted downstream in a downregulated phosphorylation levels of GSK3β (Ser9), STAT3 (Tyr705) and STAT5 (Tyr694). Combination experiments with glucocorticoids (Fig. A) and chemotherapy (Fig. B), currently used as conventional therapy in T-ALL, showed a synergistic effect when combined with PDGFR-β inhibition. In conclusion, we have shown that specific PDGFR-β inhibitors can be used as a novel and targeted therapy in PDGFR-βhigh T-ALL patients and that they can be of added value to the current chemotherapy treatment for T-ALL patients. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

Endothelial senescence mediates hypoxia-induced vascular remodeling by modulating PDGFB expression.

Uncontrolled accumulation of pulmonary artery smooth muscle cells (PASMCs) to the distal pulmonary arterioles (PAs) is one of the major characteristics of pulmonary hypertension (PH). Cellular senescence contributes to aging and lung diseases associated with PH and links to PH progression. However, the mechanism by which cellular senescence controls vascular remodeling in PH is not fully understood. The levels of senescence marker, p16INK4A and senescence-associated β-galactosidase (SA-β-gal) activity are higher in PA endothelial cells (ECs) isolated from idiopathic pulmonary arterial hypertension (IPAH) patients compared to those from healthy individuals. Hypoxia-induced accumulation of α-smooth muscle actin (αSMA)-positive cells to the PAs is attenuated in p16fl/fl-Cdh5(PAC)-CreERT2 (p16iΔEC) mice after tamoxifen induction. We have reported that endothelial TWIST1 mediates hypoxia-induced vascular remodeling by increasing platelet-derived growth factor (PDGFB) expression. Transcriptomic analyses of IPAH patient lungs or hypoxia-induced mouse lung ECs reveal the alteration of senescence-related gene expression and their interaction with TWIST1. Knockdown of p16INK4A attenuates the expression of PDGFB and TWIST1 in IPAH patient PAECs or hypoxia-treated mouse lungs and suppresses accumulation of αSMA–positive cells to the supplemented ECs in the gel implanted on the mouse lungs. Hypoxia-treated mouse lung EC-derived exosomes stimulate DNA synthesis and migration of PASMCs in vitro and in the gel implanted on the mouse lungs, while p16iΔEC mouse lung EC-derived exosomes inhibit the effects. These results suggest that endothelial senescence modulates TWIST1-PDGFB signaling and controls vascular remodeling in PH.

Platelet-Derived Growth Factors Affect Clinical Features and Prognosis of Gastric Cancer.

Purpose To investigate the association of platelet-derived growth factors (PDGFs), clinicopathological features, and prognosis in gastric cancer patients. Methods Tumor specimens of 180 individuals with gastric cancer treated between 2016 and 2020 were collected. Immunohistochemical staining and Western blot (WB) were used to detect the expression of PDGF-B and PDGF-D. The relationship between the expression of PDGF-B and PDGF-D and relapse-free subsistence (RFS) time was assessed using Kaplan–Meier curves. Univariate and multivariate Cox proportional hazards regression models were used to evaluate the relationship between the expression of PDGF-B and PDGF-D and the prognosis and clinicopathological features in gastric cancer patients. Results High expression of PDGF-B and PDGF-D was detected in 108 (60%) and 137 (76%) tumor specimens, respectively. The expressions of PDGF-B and PDGF-D were independent predictive indicators in multivariate analysis when compared to tumor depth, tumor stage, lymph node metastasis, and RFS (P < 0.01). Conclusion The high expression of PDGF-B and PDGF-D in gastric cancer tissues is associated with poor prognosis and poor survival rate of the patients. The expression of PDGF-B and PDGF-D can be used as important indicators to evaluate the biological behavior and prognosis of gastric cancer.

HDACs regulate the differentiation of endothelial cells from human iPSCs.

Human induced pluripotent stem cells (hiPSCs) possess the potential to differentiate toward vascular cells including endothelial cells (ECs), pericytes, and smooth muscle cells. Epigenetic mechanisms including DNA methylation and histone modification play a crucial role in regulating lineage differentiation and specification. Herein, we utilized a three-stage protocol to induce differentiation of mesoderm, vascular progenitors, and ECs from hiPSCs and investigated the regulatory effects of histone acetylation on the differentiation processes. We found that the expression of several histone deacetylases (HDACs), including HDAC1, HDAC5, and HDAC7, were greatly upregulated at the second stage and downregulated at the third stage. Interestingly, although HDAC1 remained in the nucleus during the EC differentiation, HDAC5 and HDAC7 displayed cytosol/nuclear translocation during the differentiation process. Inhibition of HDACs with sodium butyrate (NaBt) or BML210 could hinder the differentiation of vascular progenitors at the second stage and facilitate EC induction at the third stage. Further investigation revealed that HDAC may modulate the stepwise EC differentiation via regulating the expression of endothelial transcription factors ERG, ETS1, and MEF2C. Opposite to the expression of EC markers, the smooth muscle/pericyte marker ACTA2 was upregulated at the second stage and downregulated at the third stage by NaBt. The stage-specific regulation of ACTA2 by HDAC inhibition was likely through regulating the expression of TGFβ2 and PDGFB. This study suggests that HDACs play different roles at different stages of EC induction by promoting the commitment of vascular progenitors and impeding the later stage differentiation of ECs.

Prognostic values of immune landscape in Ras-mutant colorectal cancer peritoneal metastases.

e15583 Background: The peritoneal metastasis (PM) in patients with colorectal cancer (CRC) is associated with poor survival, especially in those with Ras mutations. However, knowledge on the mechanism of molecular biology in CRC peritoneal metastasis (CRCPM) is limited, and the impact of tumor immune microenvironment (TME) on PM pathogenesis and the prognosis of CRCPM remain unclear. Therefore, we characterized the TME of CRCPM and evaluated its potential diagnostic and prognostic values. Methods: This study involved 21 patients with metastatic CRC (mCRC), of whom 11 with CRCPM were classified into the experimental group and 10 with mCRC without PM (noCRCPM) were classified into the control group. Formalin-fixed and paraffin-embedded tissue of primary tumors from all patients was examined using the NanoString RNA sequencing system. The clinicopathological variables and TME biomarkers were compared using the chi-square test and Cox regression analysis. According to the results of multivariate analysis, a prognostic nomogram was generated, and its prediction ability was measured using the concordance index (C-index). Survival curves were generated using the Kaplan–Meier method, and survival comparison between groups was conducted using the log-rank test. Results: The TME in the CRCPM and noCRCPM groups was different, especially the expression of NOS2, TNSF9, KIR3DL2, MAGEA12, MRC1, KIR3DL1, and CD244 and the content of DC cells, macrophages, exhausted CD8+T cells, NK CD56dim cells, and M2 macrophages. Univariate analysis revealed that the expression of PTPN11, TIE1, MAGEA4, PDGFB, and PMS2 was significantly correlated with progression-free survival (PFS) time. These genes were subjected to the least absolute shrinkage and selection operator regression analysis and established a risk score model. Multiple Cox regression analysis showed that the risk score was a significant independent prognostic factor. However, considering the particularity of serum carcinoembryonic antigen (CEA), we built a combined model that included the CEA level and risk score. It could perform well in predicting the PFS time in patients with CRCPM (C-index 0.77). Conclusions: The TME of the primary lesion was significantly different between the CRCPM and noCRCPM groups. The model that combined the risk score and CEA level was a better outcome predictor among patients with CRCPM.

MO066: The Role of Platelet-Derived Growth Factor in Focal Segmental Glomerulosclerosis

Abstract BACKGROUND AND AIMS Focal segmental glomerulosclerosis (FSGS) describes a primary disease of podocytes (podocytopathy) and a secondary consequence of severe or progressive glomerular damage. No specific treatment options exist for FSGS, with many patients progressing to end-stage kidney disease. While podocyte injury is considered to initiate FSGS, parietal epithelial cells (PECs) were shown to be one of the main effector cells forming FSGS. Given the involvement of platelet-derived growth factor (PDGF) in fibrotic processes, we hypothesized that PDGF signaling is involved in the formation and progression of FSGS. METHOD We analyzed the role of PDGF in FSGS development and progression using a murine Thy1.1 trangenic FSGS model, patient kidney biopsies and primary murine PECs. In a second step, we therapeutically treated mice with FSGS with a neutralizing anti-PDGF-B antibody. RESULTS The podocyte-specific Thy1.1 transgenic mice 3 weeks after anti-Thy1.1 antibody injection showed reduced kidney function due to FSGS development. In this model, compared with control mice, PECs were progressively activated (63.3-fold increase in CD44 expression), showed a significantly increased proliferation (14-fold increase in Ki67 expression), followed by glomerular extracellular matrix deposition (2.6-fold increase in collagen 4) and FSGS development. Fluorescence in situ hybridization showed that mRNA of Pdgfb and Pdgfd was elevated in podocytes and Pdgfrb was upregulated in PECs during the time course of the disease. Similarly, in human FSGS biopsies, gene expression of both ligands, PDGFB and PDGFD, was elevated in podocytes and PDGFRB was increased in PECs compared with healthy glomeruli. Stimulation of primary mouse PECs with PDGF-B and PDGF-D in vitro led to significant activation (1.37- and 1.44-fold increase in CD44 expression, respectively), proliferation (1.46- and 1.36-fold increase, respectively), migration and extracellular matrix production (1.40-fold increase in fibronectin after PDGF-D stimulation) which could be inhibited by imatinib or a neutralizing PDGF-B antibody. In mice with FSGS, both a short- and long-term treatment with PDGF-B neutralizing antibody improved kidney function and reduced FSGS, PEC proliferation and profibrotic activation. CONCLUSION PDGFR-β and its ligands PDGF-B and PDGF-D were upregulated in experimental and clinical samples with FSGS in PECs and podocytes, respectively, and the inhibition of PDGF-B reduced PEC proliferation and FSGS development. This suggests paracrine cross-talk between injured podocytes and PECs, leading to PECs activation toward a profibrotic (pro-FSGS) phenotype and FSGS development. Thus, PDGF represents a novel molecular pathway in FSGS pathogenesis and potential target for therapy.

SU16f inhibits fibrotic scar formation and facilitates axon regeneration and locomotor function recovery after spinal cord injury by blocking the PDGFR\u03b2 pathway

BackgroundExcessively deposited fibrotic scar after spinal cord injury (SCI) inhibits axon regeneration. It has been reported that platelet-derived growth factor receptor beta (PDGFRβ), as a marker of fibrotic scar-forming fibroblasts, can only be activated by platelet-derived growth factor (PDGF) B or PDGFD. However, whether the activation of the PDGFRβ pathway can mediate fibrotic scar formation after SCI remains unclear.MethodsA spinal cord compression injury mouse model was used. In situ injection of exogenous PDGFB or PDGFD in the spinal cord was used to specifically activate the PDGFRβ pathway in the uninjured spinal cord, while intrathecal injection of SU16f was used to specifically block the PDGFRβ pathway in the uninjured or injured spinal cord. Immunofluorescence staining was performed to explore the distributions and cell sources of PDGFB and PDGFD, and to evaluate astrocytic scar, fibrotic scar, inflammatory cells and axon regeneration after SCI. Basso Mouse Scale (BMS) and footprint analysis were performed to evaluate locomotor function recovery after SCI.ResultsWe found that the expression of PDGFD and PDGFB increased successively after SCI, and PDGFB was mainly secreted by astrocytes, while PDGFD was mainly secreted by macrophages/microglia and fibroblasts. In addition, in situ injection of exogenous PDGFB or PDGFD can lead to fibrosis in the uninjured spinal cord, while this profibrotic effect could be specifically blocked by the PDGFRβ inhibitor SU16f. We then treated the mice after SCI with SU16f and found the reduction of fibrotic scar, the interruption of scar boundary and the inhibition of lesion and inflammation, which promoted axon regeneration and locomotor function recovery after SCI.ConclusionsOur study demonstrates that activation of PDGFRβ pathway can directly induce fibrotic scar formation, and specific blocking of this pathway would contribute to the treatment of SCI.

From the Editor’s Desk...

From the Editor’s Desk...

Genotoxic stress leads to the proinflammatory response of endothelial cells: an in vitro study

It was shown, that genotoxic stress can trigger endothelial disfunction and atherosclerosis, but the molecular genetic mechanisms of this process are poorly investigated. At the same time, inflammation also plays the important role in atherogenesis. This study aimed access of inflammatory marker expression in the endothelial cells exposed to alkylating mutagen mitomycin C (MMC). Primary human coronary (HCAEC) and internal thoracic artery endothelial cells (HITAEC) exposed to 500 ng/ml MMC (experimental group) and 0.9% NaCl (control) were used in this research. A gene expression profile was evaluated by quantitative reverse transcription PCR after 6 h exposure of endothelial cells to MMC (or 0.9% NaCl) followed by subsequent 24 h incubation in the mutagen-free cell growth media. The cytokine profile of endotheliocytes was studied by dot blotting. We found that MIF, IL-8, MCP-1, IP-10 and PDGFB were upregulated both in HCAEC and HITAEC, while MIP-1β release remained unchanged. TIMP-2 was upregulated in HCAEC but not in HITAEC. sTNF RI was expressed only in HCAEC. According to gene expression analysis, HCAEC exposed to MMC are characterized by the increased mRNA level of IL-8, MCP-1 and IP-10; decreased expression of TIMP-2 and no differences in the expression of MIF, MIP-1β and PDGFB compared to the control. In HITAEC, increased mRNA level of IL-8 and IP-10; decreased expression of MIF and TIMP-2, no differences in the expression of MCP-1, MIP-1β and PDGFB was shown. TNF-RI expression was not detected in both cell lines. Thus, genotoxic stress in endothelial cells induced by MMC leads to differential inflammatory response that can trigger endothelial dysfunction.

Chronic Morphine Modulates PDGFR-β and PDGF-B Expression and Distribution in the Dorsal Root Ganglion and Spinal Cord in Rats

Chronic Morphine Modulates PDGFR-β and PDGF-B Expression and Distribution in the Dorsal Root Ganglion and Spinal Cord in Rats

Conditioned Medium from Human Uterine Cervical Stem Cells Regulates Oxidative Stress and Angiogenesis of Retinal Pigment Epithelial Cells

Introduction: Retinal homeostasis is essential to avoid retinal pigment epithelium (RPE) damage resulting in photoreceptor death and blindness. Mesenchymal stem cells-based cell therapy could contribute to the maintenance of the retinal homeostasis. We have explored the effect of human uterine cervical stem cells (hUCESCs)-conditioned medium (hUCESC-CM) on RPE cells under oxidative stress condition. Methods: ARPE-19 cells were treated with hydrogen peroxide (H2O2) in the presence or absence of hUCESC-CM. qRT-PCR and Western blot were used to evaluate the expression of oxidative stress-related (HO-1, GCLC, and HSPB1) and vasculogenesis-related (VEGFA, PDGFA, and PDGFB) factors. Also, we assessed in vitro effects of hUCESC-CM on endothelial-cell (HUVEC) tube formation. Results: mRNA expression of HO-1, GCLC, HSPB1, VEGFA, PDGFA, and PDGFB were significantly increased in ARPE-19 cells treated with H2O2 + hUCESC-CM compared to cells treated with H2O2 only. Regarding the tube formation assay, HUVEC treated with supernatant from ARPE-19 cells treated with H2O2 + hUCESC-CM showed a significant increase in average vessel length, number of capillary-like junctions, and average of vessels area compared with HUVEC treated with supernatant from ARPE-19 cells treated with H2O2 only. Conclusion: Our results show potential therapeutic effects of hUCESC-CM on RPE, such as protection from damage by oxidative stress, stimulation of detoxifying genes, and a better vascularization.

Coupling induction of osteogenesis and type H vessels by pulsed electromagnetic fields in ovariectomy-induced osteoporosis in mice.

The growth of blood vessels and osteogenesis are coupled in bone tissue. A specialized subset of CD31hiEndomucinhi (CD31hiEmcnhi) vascular endothelium in bone has been identified to positively regulate bone formation. Pulsed electromagnetic field (PEMF) can promote the facture healing and reverse the loss of bone mass. However, the underlying mechanisms mediating in the positive effects of PEMF on bone mass accrual remain unclear. In the ovariectomized (OVX) osteoporotic mouse model, PEMF with specific parameters was administrated after 12weeks of surgery and continued for 8weeks. μCT analysis, quantitative PCR and Elisa assays were used to assess the PEMF-induced the osteogenesis, while immunostaining and flow cytometry were used to evaluate the abundance of CD31hiEmcnhi endothelium in the metaphysis near the growth plate. Administration of PEMF substantially countered OVX-induced bone loss as shown by greater trabecular bone, higher expression of Osterix, PDGFB and Col-1a1 transcripts, and modulation of bone anabolic and catabolic activity. The PEMF-induced osteogenesis was coupled by the expansion of CD31hiEmcnhi endothelium as demonstrated by CD31 and Endomucin double-positive immunostaining and flow cytometry. Concurrently, the higher level of HIF-α was found in PEMF-treated mice than in vehicle controls. Notably, inhibition of HIF-1α considerably reduced PEMF-induced osteogenesis, and led to a remarkable decrease of CD31hiEmcnhi vessels in the PEMF-treated OVX mice. The present study demonstrated the PEMF-induced coupling promotion of osteogenesis and CD31hiEmcnhi endothelial cells in a mouse model of postmenopausal osteoporosis. This coupling effect might be mediated in HIF-1α signaling in CD31hiEmcnhi endothelium. These findings open up new directions of al that might enable therapeutic improvement of osteogenesis in patients with osteoporosis.

EXTH-63. A NOVEL MOUSE MODEL OF DIFFUSE MIDLINE GLIOMA FOR TARGETED IMMUNOTHERAPY

Abstract In children, diffuse midline gliomas retain poor outcomes, failing to have a durable response to conventional therapies. Immunotherapies hold promise, with the integration of the host's immune system fundamental to their design. Here, we describe a novel genetically engineered immunocompetent model that incorporates interleukin 13 receptor alpha 2 (IL13Rα2), a tumor-associated antigen, to evaluate the antitumor activity of IL13Rα2-CAR T cell and bispecific T cell engager (BiTE) therapies in preclinical studies. The RCAS-Tva delivery system was utilized to induce gliomagenesis through p53 loss and the constitutive expression of PDGFB and human IL13Rα2 in Nestin-Tva;p53fl/fl mice. Pups were injected with virus-producing DF1 cells, encoding either for RCAS-Cre and PDGFB+IL13Rα2 or RCAS-Cre and PDGFB. Kaplan-Meier survival curves established and compared tumor growth dynamics in both models. Tumor tissue was characterized through immunohistochemistry and H&amp;E staining. Cell lines generated from tumor-bearing tissue were used for orthotopic injection and in vitro studies. Expression of PDGFB and IL13Rα2 was confirmed by flow cytometry and western blot. In both groups, de novo tumors developed without significant difference in median survival between RCAS:PDGFB (n=25, 40 days) and RCAS:PDGB+IL13Rα2 (n=32, 39 days). Tumors demonstrated characteristics of high-grade glioma such as infiltration, pseudopalisading necrosis, microvascular proliferation, high Ki-67 index, heterogenous IL13Rα2 expression, with notable presence of CD11b+ macrophages and low count of CD3+ T cells. Orthotopic tumors from developed cell lines were histologically similar to de novo tumors. Treatment of generated cell lines with IL13Rα2-targeting BiTE protein resulted in a loss of glioma cell viability and target-specific activation of T cells. Engineered de novo tumors possess histopathologic features common to diffused midline gliomas. IL13Rα2-positive cell lines derived from de novo tumors were responsive to targeted treatment, opening the opportunity for preclinical assessment of IL13Rα2-directed immunotherapies, with the potential for clinical translation.

CBIO-11. HISTONE H3.3 G34R/V MUTATIONS STIMULATE PEDIATRIC HIGH-GRADE GLIOMA FORMATION THROUGH THE INDUCTION OF CHROMOSOMAL INSTABILITY

Abstract H3.3 G34R/V mutations are drivers of high-grade pediatric glioma (pHGG). H3.3 G34R/V mutations are linked to altered H3.3 K36 trimethylation (H3K36me3); implicating epigenetic gene regulation as a possible contributor to pHGG formation. Here we show that H3.3 G34R/V also induces chromosomal instability (CIN); a hallmark of pHGG. If CIN promotes pHGG formation is unknown. We observed that H3.3 G34 mutant pHGG cells have reduced mitotic H3.3 S31 phosphorylation compare to WT H3.3 cell lines. And, H3.3 G34R reduced Chk1 phosphorylation at S31 by &amp;gt;90% in an in vitro kinase assay. Chk1 regulates chromosome segregation through phosphorylation of pericentromeric H3.3 S31 during early mitosis. Overexpression of H3.3 G34R or non-phosphorylatable S31A in H3.3 WT, diploid cells caused a significant increase in CIN. Likewise, H3.3 G34 mutant pHGG cells have significantly elevated rates of CIN as compare to H3.3 WT pHGG cells. During normal cell division, phospho-S31 is lost in anaphase. However, following chromosome missegregation, phospho-S31 spreads and stimulates p53-induced cell cycle arrest. Here we show that WT p53 cells expressing mutant G34 fail to arrest following chromosome mis-segregation. These studies demonstrate that H3.3 G34R/V mutations are sufficient to transform normal, diploid cells into proliferating CIN cells. To determine if this process contributes to tumorigenesis, we used RCAS Nestin-TVA mice to overexpress H3.3 WT, G34R, or S31A – P2A-linked to PDGFB expression in glial precursor cells of newborn mice. Over 100 days, S31A and G34R mice had drastically reduced survival (averaging 77, 81, and 100 days for S31A, G34R, and WT). Furthermore, most G34R and S31A mice developed HGG, while H3.3 WT mice remained tumor-free. Our work implicates CIN as a driver of H3.3 G34 mutant pHGG formation. Our ongoing studies utilize K36M and double mutants to further define the contributions of S31 phosphorylation (CIN) and H3K36me3 (epigenetic gene regulation) to tumorigenesis.

High salt diet impairs dermal tissue remodeling in a mouse model of IMQ induced dermatitis.

Recent animal studies, as well as quantitative sodium MRI observations on humans demonstrated that remarkable amounts of sodium can be stored in the skin. It is also known that excess sodium in the tissues leads to inflammation in various organs, but its role in dermal pathophysiology has not been elucidated. Therefore, our aim was to study the effect of dietary salt loading on inflammatory process and related extracellular matrix (ECM) remodeling in the skin. To investigate the effect of high salt consumption on inflammation and ECM production in the skin mice were kept on normal (NSD) or high salt (HSD) diet and then dermatitis was induced with imiquimod (IMQ) treatment. The effect of high salt concentration on dermal fibroblasts (DF) and peripheral blood mononuclear cells (PBMC) was also investigated in vitro. The HSD resulted in increased sodium content in the skin of mice. Inflammatory cytokine Il17 expression was elevated in the skin of HSD mice. Expression of anti-inflammatory Il10 and Il13 decreased in the skin of HSD or HSD IMQ mice. The fibroblast marker Acta2 and ECM component Fn and Col1a1 decreased in HSD IMQ mice. Expression of ECM remodeling related Pdgfb and activation phosphorylated (p)-SMAD2/3 was lower in HSD IMQ mice. In PBMCs, production of IL10, IL13 and PDGFB was reduced due to high salt loading. In cultured DFs high salt concentration resulted in decreased cell motility and ECM production, as well. Our results demonstrate that high dietary salt intake is associated with increased dermal pro-inflammatory status. Interestingly, although inflammation induces the synthesis of ECM in most organs, the expression of ECM decreased in the inflamed skin of mice on high salt diet. Our data suggest that salt intake may alter the process of skin remodeling.

Anoikis resistant gastric cancer cells promote angiogenesis and peritoneal metastasis through C/EBPβ-mediated PDGFB autocrine and paracrine signaling

Anoikis is a type of programmed cell death induced by loss of anchorage to the extracellular matrix (ECM). Anoikis resistance (AR) is crucial for the survival of metastatic cancer cells in blood, lymphatic circulation and distant organs. Compared to ordinary cancer cells, anoikis resistant cancer cells undergo various cellular and molecular alterations, probably characterizing the cells with unique features not limited to anoikis resistance. However, the molecular mechanisms connecting anoikis resistance to other metastatic properties are still poorly understood. Here, the biological interaction between anoikis resistance and angiogenesis as well as their involvement into peritoneal metastasis of gastric cancer (GC) were investigated in vitro and in vivo. The prognostic value of key components involved in this interaction was evaluated in the GC cohort. Compared to ordinary GC cells, GCAR cells exhibited stronger metastatic and pro-angiogenic traits corresponding to elevated PDGFB secretion. Mechanistically, transcription factor C/EBPβ facilitated PDGFB transcription by directly binding to and interacting with PDGFB promoter elements, subsequently increasing PDGFB secretion. Secreted PDGFB promoted the survival of detached GC cells through a C/EBPβ-dependent self-feedback loop. Moreover, secreted PDGFB promoted angiogenesis in metastases via activation of the MAPK/ERK signaling pathway in vascular endothelial cells. Both C/EBPβ activation level and PDGFB expression were significantly elevated in GC and correlated with metastatic progression and poor prognosis of patients with GC. Overall, interaction between GCAR cells and vascular endothelial cells promotes angiogenesis and peritoneal metastasis of GC based on C/EBPβ-mediated PDGFB autocrine and paracrine signaling. C/EBPβ-PDGFB-PDGFRβ-MAPK axis promises to be potential prognostic biomarkers and therapeutic targets for peritoneal metastasis of GC.

Hydroxysafflor Yellow a Promotes Angiogenesis in Rat Brain Microvascular Endothelial Cells Injured by Oxygen-glucose Deprivation/reoxygenation(OGD/R) through SIRT1-HIF-1α-VEGFA Signaling Pathway.

Angiogenesis led by brain microvascular endothelial cells (BMECs) contributes to the remission of brain injury after brain ischemia reperfusion. In this study, we investigated the effects of hydroxysafflor yellow A(HSYA) on angiogenesis of BMECs injured by OGD/R via SIRT1-HIF-1α-VEGFA signaling pathway. The OGD/R model of BMECs was established in vitro by OGD for 2h and reoxygenation for 24h. At first, the concentrations of vascular endothelial growth factor (VEGF), Angiopoietin (ang) and platelet-derived growth factor (PDGF) in supernatant were detected by ELISA, and the proteins expression of VEGFA, Ang-2 and PDGFB in BMECs were tested by western blot; the proliferation, adhesion, migration (scratch healing and transwell) and tube formation experiment of BMECs; the expression of CD31 and CD34 were tested by immunofluorescence staining. The levels of sirtuin1(SIRT1), hypoxia-inducible factor-1α (HIF-1α), VEGFA mRNA and protein were tested. HSYA up-regulated the levels of VEGF, Ang and PDGF in the supernatant of BMECs under OGD/R, and the protein expression of VEGFA, Ang-2 and PDGFB was increased; HSYA could significantly alleviate the decrease of cell proliferation, adhesion, migration and tube formation ability of BMECs during OGD/R; HSYA enhanced the fluorescence intensity of CD31 and CD34 of BMECs during OGD/R; HSYA remarkably up-regulated the expression of SIRT1, HIF-1α, VEGFA mRNA and protein after OGD/R, and these increase decreased after SIRT1 was inhibited. SIRT1-HIF-1α-VEGFA signaling pathway is involved in HSYA improves angiogenesis of BMECs injured by OGD/R.

Potential of thrombospondin-1 in treatment of polycystic ovary syndrome rat model: a preliminary study

Objective Polycystic ovary syndrome (PCOS) is a common gynecological endocrine disease in reproductive women, and the endocrine levels are also affected by diseases. The aim of this study was to determine the effect of thrombospondin-1 (TSP-1) on PCOS rat model. Methods We established the PCOS rat model, the serum hormones including TSP-1 expression were determined and morphological characteristics were investigated to evaluate the model. These above endocrine and morphological features were investigated again to evaluate the effect of TSP-1 treatment. Results In the PCOS model group, the serum hormones change (higher luteinizing hormone, testosterone and estrogen) and decreased TSP-1 expression levels were found compared with the control group. Besides, the morphological characteristics of PCOS were also observed in the model group. After TSP-1 treatment, the higher TSP-1, ANGPT2, PDGFB and PDGFD expression levels, the lower LH and T levels, decreased vessel density as well as VEGFA and ANGPT1 expression levels were found compared with the control group, and the ovary morphological changes were also observed in the TSP-1 experimental group. Conclusions TSP-1 delivery system might be an alternative therapy for PCOS treatment.

Interleukin-24 regulates mucosal remodeling in inflammatory bowel diseases

BackgroundRecently, increased interleukin (IL)-24 expression has been demonstrated in the colon biopsies of adult patients with inflammatory bowel disease (IBD). However, the role of IL-24 in the pathomechanism of IBD is still largely unknown.MethodsPresence of IL-24 was determined in the samples of children with IBD and in the colon of dextran sodium sulfate (DSS) treated mice. Effect of inflammatory factors on IL24 expression was determined in peripheral blood (PBMCs) and lamina propria mononuclear cells (LPMCs). Also, the impact of IL-24 was investigated on HT-29 epithelial cells and CCD-18Co colon fibroblasts. Expression of tissue remodeling related genes was investigated in the colon of wild type (WT) mice locally treated with IL-24 and in the colon of DSS treated WT and Il20rb knock out (KO) mice.Results Increased amount of IL-24 was demonstrated in the serum and colon samples of children with IBD and DSS treated mice compared to that of controls. IL-1β, LPS or H2O2 treatment increased the expression of IL24 in PBMCs and LPMCs. IL-24 treatment resulted in increased amount of TGF-β and PDGF-B in HT-29 cells and enhanced the expression of extracellular matrix (ECM)-related genes and the motility of CCD-18Co cells. Similarly, local IL-24 treatment increased the colonic Tgfb1 and Pdgfb expression of WT mice. Moreover, expression of pro-fibrotic Tgfb1 and Pdgfb were lower in the colon of DSS treated Il20rb KO compared to that of WT mice. The disease activity index of colitis was less severe in DSS treated Il20rb KO compared to WT mice.ConclusionOur study suggest that IL-24 may play a significant role in the mucosal remodeling of patients with IBD by promoting pro-fibrotic processes.

PDGFB RNA in situ hybridization for the diagnosis of dermatofibrosarcoma protuberans.

Dermatofibrosarcoma protuberans (DFSP) is a spindle cell neoplasm of the skin and superficial soft tissue with a tendency for locally aggressive behavior; metastatic potential coincides with fibrosarcomatous transformation. The vast majority of DFSPs harbor the t(17;22) translocation resulting in a COL1A1-PDGFB fusion that drives autocrine growth stimulation via PDGFB overexpression. Here, we examined the utility of PDGFB RNA chromogenic in situ hybridization (CISH) for the diagnosis of DFSP. A total of 337 tumors represented in whole tissue sections and tissue microarrays, including 37 cases of DFSP and 300 histologically similar spindle cell tumors, were subjected to PDGFB RNA CISH using commercially available probes. PDGFB overexpression was observed by light microscopy in 24 of 26 conventional DFSPs (92%) and 11 of 11 fibrosarcomatous DFSPs (100%). One of two DFSPs negative for PDGFB by RNA CISH was found to harbor an uncommon alternative rearrangement involving PDGFD. All examined cases of histologic mimics were negative for PDGFB overexpression; limited PDGFB expression, not reaching an empirical threshold of greater than 5 puncta or one aggregate of chromogen in more than 25% of cells, was observed in 7 of 300 mimics (2.3%), including desmoplastic melanoma, malignant peripheral nerve sheath tumor, angiosarcoma, and pleomorphic dermal sarcoma. Vascular PDGFB expression was seen in several tumor types. We conclude that PDGFB RNA CISH, with careful interpretation and the use of appropriate thresholds, may serve as a surrogate marker of PDGFB rearrangement and a useful ancillary tool for the diagnosis of DFSP.