Expression Of Various Angiogenic Factors Research Articles

The Antimicrobial Peptides Human β-Defensins Induce the Secretion of Angiogenin in Human Dermal Fibroblasts.

The skin produces a plethora of antimicrobial peptides that not only show antimicrobial activities against pathogens but also exhibit various immunomodulatory functions. Human β-defensins (hBDs) are the most well-characterized skin-derived antimicrobial peptides and contribute to diverse biological processes, including cytokine production and the migration, proliferation, and differentiation of host cells. Additionally, hBD-3 was recently reported to promote wound healing and angiogenesis, by inducing the expression of various angiogenic factors and the migration and proliferation of fibroblasts. Angiogenin is one of the most potent angiogenic factors; however, the effects of hBDs on angiogenin production in fibroblasts remain unclear. Here, we investigated the effects of hBDs on the secretion of angiogenin by human dermal fibroblasts. Both in vitro and ex vivo studies demonstrated that hBD-1, hBD-2, hBD-3, and hBD-4 dose-dependently increased angiogenin production by fibroblasts. hBD-mediated angiogenin secretion involved the epidermal growth factor receptor (EGFR), Src family kinase, c-Jun N-terminal kinase (JNK), p38, and nuclear factor-kappa B (NF-κB) pathways, as evidenced by the inhibitory effects of specific inhibitors for these pathways. Indeed, we confirmed that hBDs induced the activation of the EGFR, Src, JNK, p38, and NF-κB pathways. This study identified a novel role of hBDs in angiogenesis, through the production of angiogenin, in addition to their antimicrobial activities and other immunomodulatory properties.

Free-cell therapeutics and mechanism of exosomes from adipose-derived stem cells in promoting wound healing: current understanding and future applications.

Free-cell therapeutics and mechanism of exosomes from adipose-derived stem cells in promoting wound healing: current understanding and future applications.

PO-444 Evaluation of novel nucleoside analogues for lung cancer treatment: an approach based on metronomic chemotherapy

IntroductionLung cancer presents a global pandemic responsible for an estimated 20% of cancer cases with Non-Small Cell Lung Cancer (NSCLC) being the most prevalent form. Chemotherapy is the preferred treatment modality for NSCLC, focusing on the disruption of the abnormal proliferation of cancer cells. Nevertheless, this approach causes patients to experience unpleasant side effects and more importantly, results in cancer recurrence. Gemcitabine (Gemc) is a nucleoside analogue used against NSCLC, which inhibits cell cycle and prevents tumour growth. Although gemc is approved for the treatment of various cancer types, its efficacy is still limited due to its lack of efficiency, which is caused by rapid metabolic inactivation. Metronomic chemotherapy (MTR), relying on the daily oral administration of a drug, at low doses, is a multi-targeted therapy, as it inhibits tumour angiogenesis, modulates immunity pathways and effects tumour initiating cells reducing the toxicity of traditional maximal tolerated dose chemotherapy (MTD). Our goal is to provide a new angle in the MTR approach, by administering an oral prodrug of gemc, Oral Gem, to improve gemc’s therapeutic properties, but also cover patients‘ quality of life.Material and methodsThe A549 lung cancer cell line was used to establish an in vitro model that simulated the MTD versus the MTR conditions. Cells were cultured either in presence of a high concentration of gemc or in medium in which lower concentrations were added daily in order to study alterations in the expression of various angiogenic factors. Additionally, an in vivo xenografted animal model was set up to study the effects of MTR chemotherapy on tumour’s expansion, toxicity of the drug and angiogenesis.Results and discussionsDaily addition of gemc in A549 cells led to a decreased expression of VEGFA, a well-established angiogenic factor, compared to the high dose incubation. In NOD/SCID xenografted mice, the MTR administration of Oral Gem led to a decreased expression of VEGFA and CD31, a marker found on endothelial cells, suggesting a suppressed angiogenic profile. Finally, MTR administration of Oral Gem led to an increase in the expression levels of Thrombospondin-1, an anti-angiogenic factor, compared to MTD chemotherapy.ConclusionMTR administration of Oral Gem limits the formed vessels around the tumour combining restriction of angiogenesis and vessel normalisation. In contrast, MTD chemotherapy seems to enhance the angiogenic potential around the tumour site, serving tumour’s establishment and expansion.

Distinct patterns of angiogenic factor expression as a predictive factor of response to chemotherapy in stage IIIA non-small-cell lung cancer patients.

The expression of various angiogenic factors was assessed in tumour samples of patients with stage III non-small-cell lung cancer (NSCLC) and further evaluated in terms of response to induction paclitaxel-ifosfamide-cisplatin chemotherapy. Freshly isolated lung tumour specimens obtained by bronchoscopy from 70 stage IIIA NSCLC chemotherapy-naïve patients were sampled and analysed for vascular endothelial growth factor receptor (VEGFR)-1, VEGFR-2 and VEGFR-3. Microvessel density was assessed through evaluating the angiogenic markers CD34 and CD105. Immunostaining scores were calculated by multiplying the percentage of labeled cells by the intensity of staining for each examined parameter. The overall mean immunostaining score value from all NSCLC samples was 7.83, 5.56 and 15.86 for VEGFR-1, VEGFR-2 and VEGFR-3, respectively. The overall mean value of the endothelial antigen CD34 was 16.29, whereas the expression of the CD105 antigen in endothelial cells yielded a multivariate distribution. Patients who responded to chemotherapy expressed significantly higher VEGFR-1 and VEGFR-3 mean values compared with non-responders (P<0.001). No significant difference was noted in VEGFR-2 mean values between these two groups (P=0.06). The CD34 mean value was significantly higher in responders (P<0.001), whereas there was no significant difference in CD105 expression between the two groups (P=0.07). Angiogenic marker expression proved to be a potential predictive factor of response to chemotherapy in stage III NSCLC. which merits further investigation.

Immunohistochemical Expression of Angiogenic Factors by Neoplastic Epithelial Cells Is Associated With Canine Prostatic Carcinogenesis

The dog is the only species, other than humans, in which spontaneous prostatic cancer occurs; therefore, dogs are a valuable model for the study of factors that regulate tumor progression. Angiogenesis is important in the development and spread of a variety of cancers, including prostate cancer. To better define the role of cancer epithelial cells in prostate cancer neovascularization, immunohistochemical staining for angiogenic factors (vascular endothelial growth factor [VEGF], platelet endothelial cell adhesion molecule-1 [PECAM-1], Tie-2, and fibroblast growth factor-2 [FGF-2]) was performed on formalin-fixed, paraffin-embedded tissues from 10 normal prostates, 15 hyperplastic prostates, and 11 prostatic carcinomas from dogs. Normal and hyperplastic epithelial cells were negative for PECAM-1, VEGF, and Tie-2, while the same markers were expressed with a variable intensity of cytoplasmic staining by neoplastic cells. Mild to moderate FGF-2 staining was detected in all normal prostates with less than 10% of positive cells, mainly distributed in the basal layer. The percentage of FGF-2-positive hyperplastic cells was variable, with both basal and secretory cells exhibiting a perinuclear to diffuse cytoplasmic staining. The mean number of positive cells and the intensity of staining were higher in prostatic carcinomas than normal and hyperplastic prostates. Moreover, microvessel density analyzed on PECAM-1-stained slides was increased in prostate cancer compared with normal and hyperplastic prostates. Therefore, prostatic neoplastic cells are capable of simultaneous expression of various angiogenic factors and may increase tumor proliferation and angiogenesis in a paracrine and autocrine fashion.

Expression of angiogenic factors in hepatocarcinogenesis: Identification by antibody arrays

Angiogenesis plays a pivotal role in the progression and metastasis of hepatocellular carcinoma (HCC). However, the expression of a wide range of angiogenic factors remains obscure in HCC. The purpose of the present study was to determine the expression of various angiogenic factors related to hepatocarcinogenesis. We examined the expression of 19 angiogenic factors using antibody arrays in human tissues of various liver diseases, including HCC. We also studied the expression of 19 angiogenic factors in the human HCC cell lines PLC/PRF/5, Hep 3B, HuH7, HLE, HLF and Li-7 and the normal hepatocyte cell line ACBRI3716. In human tissues, although the expression of acidic fibroblast growth factor (aFGF) was found to increase from normal liver to chronic hepatitis, its expression remained unchanged in the transition from chronic hepatitis to HCC. Vascular endothelial growth factor (VEGF) was elevated in liver cirrhosis, but the amounts remained unchanged in the transition from liver cirrhosis to HCC. In contrast, either interleukin-8 (IL-8) or basic fibroblast growth factor (bFGF) was upregulated in HCC. In the HCC cell lines PLC/PRF/5, Hep 3B and HuH-7, the expression of IL-8 was elevated. Although IL-8 was not elevated, bFGF was upregulated in the other HCC cell lines HLE, HLF and Li-7. Thus, either IL-8 or bFGF was upregulated in HCC cell lines and in HCC tissue samples. These data suggest that the upregulation of either IL-8 or bFGF is closely related to the transition from liver cirrhosis into HCC. Therefore, the analysis of the expression of these cytokines using protein arrays may identify novel therapies for individual patients with HCC.

Imbalance of expression of bFGF and PK1 is associated with defective maturation and antenatal placental insufficiency

ObjectiveDefective placental maturation is associated with restricted functional capacity and adverse perinatal fetal outcomes. The aim of the study was a comparative analysis of the role of mRNA expression of various angiogenic factors in placental maturation defects. Study designWe examined the mRNA expression patterns of prokineticin 1 (PK1), its receptors (PKRs), basic-fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) in tissue from third-trimester placentae that exhibited delayed or accelerated villous maturation. ResultsThe expression of PK1 and PKR2 was elevated in placental tissue exhibiting accelerated maturation and a predominant differentiation of terminal villi. The opposite was found in tissue exhibiting delayed maturation and deficiency of the terminal villi. In addition, low expression of bFGF correlated with the predominant differentiation of terminal villi, whereas the opposite was observed when terminal villi were deficient. The expression of VEGF, PIGF, and PKR1 showed no significant differences between the groups. ConclusionDefective placental maturation is associated with an imbalance of expression of bFGF and PK1. Our results demonstrate an involvement of the PK1/PKR2-signalling pathway in the regulation of the functional adequate capillarization in late pregnancy. We propose the bFGF/PK1-ratio as a monitor of placental function and a possible indicator of latent clinical problems, such as placental dysfunction leading to fetal hypoxia.

Investigation of angiogenetic pathways in nasal polyposis

Tissue angiogenesis is a complex phenomenon that results in the growth of new blood vessels from the microcirculation. This process has been known to play a crucial role in tumor growth as well as several benign diseases. The aim of this study was to assess mRNA expression of various angiogenic factors and chemokines in nasal polyps and compare the results to normal nasal mucosa. mRNA expression was measured using real-time RT-PCR for the following angiogenic factors and chemokines: VEGF, VEGFR-1, Ang-1, Ang-2, Tie-2A, Tie-2B, SDF-1α, SDF-1β, CXCR4 and YY1. Biopsy specimens from nasal polyps in the polyposis group and middle turbinates in the control group were studied. A total of 18 nasal polyposis patients were studied and compared to 10 control subjects. Results showed VEGF, VEGFR-1, Ang-1, Ang-2, Tie-2A, Tie-2B, SDF-1α and SDF-1β mRNA expression to be significantly higher in nasal polyposis patients compared to the control group (p<0.05). The findings of this study support the role of angiogenic growth factors in the pathogenesis of nasal polyposis. Further studies are required to confirm these results and evaluate potential clinical implications.

Radiation Attenuates Physiological Angiogenesis by Differential Expression of VEGF, Ang-1, Tie-2 and Ang-2 in Rat Brain

The etiology of radiation-induced cerebrovascular rarefaction remains unknown. In the present study, we examined the effect of whole-brain irradiation on endothelial cell (EC) proliferation/apoptosis and expression of various angiogenic factors in rat brain. F344 × BN rats received either whole-brain irradiation (a single dose of 10 Gy γ rays) or sham irradiation and were maintained for 4, 8 and 24 h after irradiation. Double immunofluorescence staining was employed to visualize EC proliferation/apoptosis in brain. The mRNA and protein expression levels of vascular endothelial growth factor (VEGF), angiopoietin-1 (Ang-1), endothelial-specific receptor tyrosine kinase (Tie-2), and Ang-2 in brain were determined by real-time RT-PCR and immunofluorescence staining. A significant reduction in CD31-immunoreactive cells was detected in irradiated rat brains compared with sham-irradiated controls. Whole-brain irradiation significantly suppressed EC proliferation and increased EC apoptosis. In addition, a significant decrease in mRNA and protein expression of VEGF, Ang-1 and Tie-2 was observed in irradiated rat brains. In contrast, whole-brain irradiation significantly upregulated Ang-2 expression in rat brains. The present study provides novel evidence that whole-brain irradiation differentially affects mRNA and protein expression of VEGF, Ang-1, Tie-2 and Ang-2. These changes are closely associated with decreased EC proliferation and increased EC apoptosis in brain.

Vascular Endothelial Growth Factor C Gene Expression Is Closely Related to Invasion Phenotype in Gynecological Tumor Cells

Objective. The correlation between the gene expression of various angiogenic factors and in vitro invasive activity in 16 human gynecological cancer cell lines was investigated.Methods. Semiquantitative reverse transcription polymerase chain reaction analysis was performed to investigate the mRNA expression levels of vascular endothelial growth factors (VEGF-A, -B, -C, and -D), basic fibroblast growth factor (bFGF), and matrix metalloproteinase (MMP)-2 with β-actin coamplified as an internal standard. Tumor cell migration along a gradient of substratum-bound fibronectin and invasion into reconstituted basement membrane were evaluated by haptotactic migration and invasion assay.Results. Expression of VEGF-A mRNA was detected in all 16 cell lines, whereas the relative expression levels of other VEGF family members and bFGF, differed markedly among the cell lines. There was a statistical correlation between VEGF-C gene expression and the number of cells that migrated and invaded (P < 0.01). However, expression of mRNAs of other angiogenic factors did not correlate with motility and invasive activity of the cells. Moreover, there was a close correlation between VEGF-C and MMP-2 gene expression levels (P < 0.05).Conclusion. Tumor cells that produce VEGF-C may have a higher invasive and metastatic potential because of their capacity to pass through tissue barriers.

Villous sprouting: fundamental mechanisms of human placental development.

There is increasing evidence that maldevelopment of the placental villous tree can play an important role in the pathogenesis of various pregnancy diseases. In this review we present the most recent advances of cellular and molecular mechanisms involved in the early formation of chorionic villi. In particular we focus our attention on the structural events during early villous sprouting leading to the formation of the mesenchymal villi which are the forerunners of all other villous types, i.e. immature intermediate villi, stem villi, mature intermediate villi and terminal villi. Early villous sprouting starts as 'hot spots' which are circumscribed areas consisting of highly proliferating cytotrophoblastic and stromal cells. The post-proliferative cytotrophoblastic cells fuse with the overlying syncytium leading to the formation of the trophoblastic sprouts. When villous mesenchyme invades the trophoblastic sprouts, the latter are transformed into villous sprouts. The vascularization of the villous sprouts leads to the formation of the mesenchymal villi, the most basic villous type. This process is repeated throughout pregnancy. We analyse the influence of various extracellular matrix molecules, e.g. tenascin and hyaluronic acid, on the formation of hot spots and mesenchymal villi as well as the transformation of the latter in other villous types. We present a critical survey on the data on vessel formation related to villous sprouting and morphogenesis of mesenchymal villi as well as the expression of various angiogenic factors and their receptors.