Immunoreactive fibroblast growth factor in cells of peritoneal exudate suggests its identity with macrophage-derived growth factor

Tumor Immunology and Immunotherapy of Non-Small-Cell Lung Cancer

Historically, non-small-cell lung cancer (NSCLC) has been regarded as a nonimmunogenic tumor; however, recent studies have shown that NSCLCs are among the most responsive cancers to monoclonal antibody immune checkpoint inhibitors (ICIs). ICIs have dramatically improved clinical outcomes for a subset of patients (∼20%) with locally advanced and metastatic NSCLC, and they have also demonstrated promise as neoadjuvant therapy for early-stage resectable disease. Nevertheless, the majority of patients with NSCLC are refractory to ICIs for reasons that are poorly understood. Thus, major questions are: how do we initially identify the patients most likely to derive significant clinical benefit from these therapies; how can we increase the number of patients benefiting; what are the mechanisms of primary and acquired resistance to immune-based therapies; are there additional immune checkpoints besides PD-1/PD-L1 and CTLA-4 that can be targeted to provide greater clinical benefit to patients; and how do we best combine ICI therapy with surgery, radiotherapy, chemotherapy, and targeted therapy? To answer these questions, we need to deploy the latest technologies to study tumors and their microenvironment and how they interact with components of the innate and adaptive immune systems. There is also a need for new preclinical model systems to investigate the molecular mechanisms of resistance to treatment and identify novel therapeutic targets. Recent advances in technology are beginning to shed new light on the immune landscape of NSCLC that may uncover biomarkers of response and maximize the clinical benefit of immune-based therapies. Identification of the mechanisms of resistance should lead to the identification of novel targets and the generation of new therapeutic strategies that improve outcomes for a greater number of patients. In the sections below, we discuss the results of studies examining the immune microenvironment in NSCLC, summarize the clinical experience with immunotherapy for NSCLC, and review candidate biomarkers of response to these agents in NSCLC.

Tumor-Associated Neutrophils and Macrophages-Heterogenous but Not Chaotic

Tumor-associated macrophages (TAMs) and tumor-associated neutrophils (TANs) have been extensively studied. Their pleotropic roles were observed in multiple steps of tumor progression and metastasis, and sometimes appeared to be inconsistent across different studies. In this review, we collectively discussed many lines of evidence supporting the mutual influence between cancer cells and TAMs/TANs. We focused on how direct interactions among these cells dictate co-evolution involving not only clonal competition of cancer cells, but also landscape shift of the entire tumor microenvironment (TME). This co-evolution may take distinct paths and contribute to the heterogeneity of cancer cells and immune cells across different tumors. A more in-depth understanding of the cancer-TAM/TAN co-evolution will shed light on the development of TME that mediates metastasis and therapeutic resistance.

Predictors affecting myopic regression in - 6.0D to - 10.0D myopia after laser-assisted subepithelial keratomileusis and laser in situ keratomileusis flap creation with femtosecond laser-assisted or mechanical microkeratome-assisted

PURPOSE

To investigate the predictive factors of postoperative myopic regression among subjects who have undergone laser-assisted subepithelial keratomileusis (LASEK), laser-assisted in situ keratomileusis (LASIK) flap created with a mechanical microkeratome (MM), and LASIK flap created with a femtosecond laser (FS). All recruited patients had a manifest spherical equivalence (SE) from - 6.0D to - 10.0D myopia.

METHODS

This retrospective, observational case series study analyzed outcomes of refraction at 1 day, 1 week, and 1, 3, 6, and 12 months postoperatively. Predictors affecting myopic regression and other covariates were estimated with the Cox proportional hazards model for the three types of surgeries.

RESULTS

The study enrolled 496 eyes in the LASEK group, 1054 eyes in the FS-LASIK group, and 910 eyes in the MM-LASIK group. At 12 months, from - 6.0D to - 10.0D myopia showed that the survival rates (no myopic regression) were 52.19%, 59.12%, and 58.79% in the MM-LASIK, FS-LASIK, and LASEK groups, respectively. Risk factors for myopic regression included thicker postoperative central corneal thickness (P ≦ 0.01), older age (P ≦ 0.01), aspherical ablation (P = 0.02), and larger transitional zone (TZ) (P = 0.03). Steeper corneal curvature (K_max) (P = 0.01), thicker preoperative central corneal thickness (P < 0.01), smaller preoperative myopia (P < 0.01), longer duration of myopia (P = 0.02), with contact lens (P < 0.01), and larger optical zone (OZ) (P = 0.02) were protective factors. Among the three groups, the MM-LASIK had the highest risk of postoperative myopic regression (P < 0.01).

CONCLUSIONS

The MM-LASIK group experienced the highest myopic regression, followed by the FS-LASIK and LASEK groups. Older age, aspheric ablation used, thicker postoperative central corneal thickness, and enlarging TZ contribute to myopic regression; steeper preoperative corneal curvature (K_max), longer duration of myopia, with contact lens, thicker preoperative central corneal thickness, lower manifest refraction SE, and enlarging OZ prevent postoperative myopic regression in myopia from - 6.0D to - 10.0D.

Long Pentraxin-3 Modulates the Angiogenic Activity of Fibroblast Growth Factor-2

Angiogenesis, the process of new blood vessel formation from pre-existing ones, plays a key role in various physiological and pathological conditions. Alteration of the angiogenic balance, consequent to the deranged production of angiogenic growth factors and/or natural angiogenic inhibitors, is responsible for angiogenesis-dependent diseases, including cancer. Fibroblast growth factor-2 (FGF2) represents the prototypic member of the FGF family, able to induce a complex “angiogenic phenotype” in endothelial cells in vitro and a potent neovascular response in vivo as the consequence of a tight cross talk between pro-inflammatory and angiogenic signals. The soluble pattern recognition receptor long pentraxin-3 (PTX3) is a member of the pentraxin family produced locally in response to inflammatory stimuli. Besides binding features related to its role in innate immunity, PTX3 interacts with FGF2 and other members of the FGF family via its N-terminal extension, thus inhibiting FGF-mediated angiogenic responses in vitro and in vivo. Accordingly, PTX3 inhibits the growth and vascularization of FGF-dependent tumors and FGF2-mediated smooth muscle cell proliferation and artery restenosis. Recently, the characterization of the molecular bases of FGF2/PTX3 interaction has allowed the identification of NSC12, the first low molecular weight pan-FGF trap able to inhibit FGF-dependent tumor growth and neovascularization. The aim of this review is to provide an overview of the impact of PTX3 and PTX3-derived molecules on the angiogenic, inflammatory, and tumorigenic activity of FGF2 and their potential implications for the development of more efficacious anti-FGF therapeutic agents to be used in those clinical settings in which FGFs play a pathogenic role.

Fibrin-based delivery strategies for acute and chronic wound healing

Fibrin, a natural hydrogel, is the end product of the physiological blood coagulation cascade and naturally involved in wound healing. Beyond its role in hemostasis, it acts as a local reservoir for growth factors and as a provisional matrix for invading cells that drive the regenerative process. Its unique intrinsic features do not only promote wound healing directly via modulation of cell behavior but it can also be fine-tuned to evolve into a delivery system for sustained release of therapeutic biomolecules, cells and gene vectors. To further augment tissue regeneration potential, current strategies exploit and modify the chemical and physical characteristics of fibrin to employ combined incorporation of several factors and their timed release. In this work we show advanced therapeutic approaches employing fibrin matrices in wound healing and cover the many possibilities fibrin offers to the field of regenerative medicine.

Fibrin matrices: The versatile therapeutic delivery systems

Fibrin sealants, that have been employed for over a century by surgeons to stop post surgery bleeding, are finding novel applications in the controlled delivery of antibiotics and several other therapeutics. Fibrinogen can be easily purified from blood plasma and converted by thrombolysis to fibrin that undergoes spontaneous aggregation to form insoluble clot. During the gelling, fibrin can be formulated into films, clots, threads, microbeads, nanoconstructs and nanoparticles. Whole plasma clots in the form of beads and microparticles can also be prepared by activating endogenous thrombin, for possible drug delivery. Fibrin formulations offer remarkable scope for controlling the porosity as well as in vivo degradability and hence the release of the associated therapeutics. Binding/covalent-linking of therapeutics to the fibrin matrix, crosslinking of the matrix with bifunctional reagents and coentrapment of protease inhibitors have been successful in regulating both in vitro and in vivo release of the therapeutics. The release rates can also be remarkably lowered by preentrapment of therapeutics in insoluble particles like liposomes or by anchoring them to the matrix via molecules that bind them as well as fibrin.

Association between fibroblast growth factor receptor 4 Gly388Arg polymorphism and ischaemic stroke

OBJECTIVE

Fibroblast growth factors (FGFs) and their receptors (FGFRs) play important roles in the vascular system. The FGFR4 rs351855 (Gly388Arg) poly morphism has been shown to be a risk factor for many diseases. This case-control study investigated the association between the FGFR4 Gly388Arg polymorphism and susceptibility to ischaemic stroke in the Chinese population.

METHODS

The FGFR4 Gly388Arg polymorphism was detected by polymerase chain reaction-restriction fragment length polymorphism in patients with ischaemic stroke and healthy controls.

RESULTS

Frequencies of genotypes GA and AA, and prevalence of the A allele, were significantly lower in ischaemic stroke patients (n = 952) than in controls (n = 986). Genotype AA and allele A were significantly more frequent in stroke patients with, than in those without, diabetes.

CONCLUSION

These results suggested that the GA genotype, AA genotype and A allele of FGFR4 Gly388Arg polymorphism are all associated with decreased risk of ischaemic stroke in the Chinese population.

Enhanced random skin flap survival by sustained delivery of fibroblast growth factor 2 in rats

BACKGROUND

Skin flap survival is a major challenge in reconstructive plastic surgery. Here, we examined the effect of sustained delivery of fibroblast growth factor 2 (FGF2) using heparin-conjugated fibrin (HCF) on skin flap survival in rats.

METHODS

Rats with a skin flap received either phosphate-buffered saline/FGF2 or HCF/FGF2 in the recipient bed. For the no-treatment group, a random skin flap was sutured on the back without any treatment. Seven days after surgery, angiogenesis in the skin flap was evaluated by using Visitrak system and conventional healing quality scoring method. The efficacy of HCF/FGF2 in skin flap survival was evaluated by comparing the results from different groups.

RESULTS

The necrotic area of the skin flap significantly decreased in the HCF/FGF2 group as compared with the other groups.

CONCLUSION

The sustained delivery of FGF2 using HCF has a therapeutic potential to improve skin flap survival.

Fibroblast growth factor receptor 4 polymorphisms and coronary artery disease: a case control study

Fibroblast growth factors (FGFs) and their receptors (FGFRs) play important roles in vascular system. FGFR4 rs351855 (Gly388Arg) polymorphism has shown to be a risk factor for many diseases. The aim of this study was to investigate the association between FGFR4 polymorphisms and the susceptibility to coronary artery disease (CAD) in the Chinese population. We identified three polymorphisms in the FGFR4 gene, rs351855G/A (Gly388Arg), rs145302848C/G and rs147603016G/A, by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 658 CAD cases and 692 healthy controls. Results showed that frequencies of GA genotype, AA genotype and A allele in rs351855 (Gly388Arg) polymorphism were significantly lower in CAD patients than in controls [odds ratio (OR) = 0.79, 95 % confidence intervals (CI) 0.62-0.99, P = 0.042; OR = 0.58, 95 % CI 0.41-0.81, P = 0.002; and OR = 0.77, 95 % CI 0.66-0.90, P = 0.001, respectively]. The rs147603016GA genotype and A allele also showed lower numbers in CAD cases (OR = 0.58, 95 % CI 0.36-0.93, P = 0.025; and OR = 0.59, 95 % CI 0.40-0.95, P = 0.028). The rs145302848C/G polymorphism did not show any correlation with CAD. Haplotype analysis revealed that the prevalence of ACG haplotype (rs351855, rs145302848 and rs147603016) was significantly decreased in CAD patients (P = 0.002). Our data suggested that the FGFR4 rs351855G/A (Gly388Arg) and rs147603016G/A polymorphisms could act as protective factors against CAD in the Chinese population and indicated that a single gene polymorphism could have diverse functions in different diseases.

Fibroblast growth factor receptor 4 polymorphisms are associated with coronary artery disease

Fibroblast growth factor receptor 4 (FGFR4) plays crucial roles in vascular smooth muscle cell proliferation and atherosclerosis and, therefore, may potentially affect the development of coronary artery disease (CAD). The aim of this study was to investigate the association between FGFR4 polymorphisms and the susceptibility to CAD in the Chinese population. Two polymorphisms, rs192201146G/A (Asp756Asn) and rs188755817C/G (Ser778Arg), were detected by polymerase chain reaction-restriction fragment length polymorphism and direct sequencing in 722 CAD cases and 802 age-matched controls. Data were analyzed using the chi-square test. Results showed that frequencies of rs192201146GA genotype and rs188755817CG genotype were significantly higher in CAD patients than in controls (odds ratio [OR]=1.92, 95% confidence interval [CI] 1.11-3.28, p=0.016, and OR=1.87, 95% CI 1.06-3.30, p=0.027). Similarly, numbers of the rs192201146A allele and the rs188755817G allele were significantly increased in CAD cases (OR=1.89, 95% CI 1.11-3.22, p=0.017, and OR=1.85, 95% CI 1.06-3.24, p=0.029). Haplotype analysis revealed that GG and AC (rs192201146 rs188755817) haplotypes had higher frequencies in CAD patients (OR=2.75, p=0.002 and OR=2.69, p=0.001). Our data suggested that the FGFR4 rs192201146 (Asp756Asn) and rs188755817 (Ser778Arg) polymorphisms could act as risk factors for CAD in the Chinese population.

Cytokines in pericardial effusion of patients with inflammatory pericardial disease

BACKGROUND

The role of inflammatory and angiogenic cytokines in patients with inflammatory pericardial effusion still remains uncertain.

METHODS

We assessed pericardial and serum levels of VEGF, bFGF, IL-1β and TNF-α by ELISA in patients with inflammatory pericardial effusion (PE) of autoreactive (n = 22) and viral (n = 11) origin, and for control in pericardial fluid (PF) and serum (n = 26) of patients with coronary artery disease (CAD) undergoing coronary artery bypass graft surgery.

RESULTS

VEGF levels were significantly higher in patients with autoreactive and viral PE than in patients with CAD in both PE (P = 0.006 for autoreactive and P < 0.001 for viral PE) and serum (P < 0.001 for autoreactive and P < 0.001 for viral PE). Pericardial bFGF levels were higher compared to serum levels in patients with inflammatory PE and patients with CAD (P ≤ 0.001 for CAD; P ≤ 0.001 for autoreactive PE; P = 0, 005 for viral PE). Pericardial VEGF levels correlated positively with markers of pericardial inflammation, whereas pericardial bFGF levels showed a negative correlation. IL-1β and TNF-α were detectable only in few PE and serum samples.

CONCLUSIONS

VEGF and bFGF levels in pericardial effusion are elevated in patients with inflammatory PE. It is thus possible that VEGF and bFGF participate in the pathogenesis of inflammatory pericardial disease.

Fibroblast growth factor receptor 4 polymorphisms and susceptibility to coronary artery disease

Fibroblast growth factors (FGFs) and their receptors (FGFRs) play crucial roles in vascular smooth muscle cell proliferation and atherosclerosis and, therefore, may potentially affect the development of coronary artery disease (CAD). FGFR4 rs351855 (Gly388Arg) polymorphism has shown to be a risk factor for many diseases. The aim of this study was to investigate the association between FGFR4 polymorphisms and the susceptibility to CAD in the Chinese population. Two polymorphisms, rs351855 (Gly388Arg) and rs641101, were detected by polymerase chain reaction-restriction fragment length polymorphism and direct sequencing in 687 CAD cases and 732 age-matched controls. Data were analyzed using the chi-square test. Results showed that frequencies of GA genotype, AA genotype, and A allele in rs351855 (Gly388Arg) polymorphism were significantly lower in CAD patients than in controls (odds ratio (OR)=0.78, 95% confidence intervals (CIs): 0.62-0.98, p=0.034; OR=0.58, 95% CI: 0.42-0.80, p=0.001; and OR=0.77, 95% CI: 0.66-0.90, p=0.001, respectively). The rs641101 polymorphism did not show any correlation with CAD. Haplotype analysis revealed that rs351855 and rs641101 AG haplotype also had lower frequency in CAD patients (OR=0.79, 95% CI: 0.67-0.92, p=0.002). Our data suggested that the FGFR4 rs351855 (Gly388Arg) polymorphism and AG haplotype (rs351855 and rs641101) could act as protective factors against CAD in the Chinese population and indicated that a single gene polymorphism could have diverse functions in different diseases.

Osteopontin Induced by Macrophages Contribute to Metachronous Liver Metastases in Colorectal Cancer

Even after radical surgery for stage II and stage III colorectal cancer, metachronous liver metastasis is frequently observed. The aim of this study was to identify the risk of metachronous liver metastasis with retrospective clinicopathological study. Immunohistochemistry was performed to evaluate the expression of Osteopontin (OPN), CD-68, and CD105 in 41 cases of stage II and stage III colorectal cancer tissue. Stage II and stage III colorectal cancer patients who had undergone R0 resection were classified into two groups: with metachronous liver metastasis (m-LM; n = 17) and without liver metastases (control; n = 24). Additionally, double-immunofluorescence staining was performed using antibodies to OPN and CD68. OPN-positive cells were frequently colocalized with CD68 immunoreactivity. OPN and microvascular density expression in the central area were significantly higher in the m-LM (OPN; control 4.3 ± 0.56, m-LV 10.8 ± 1.48, P < 0.05; microvascular density control 18.5 ± 2.86, m-LV 31.4 ± 4.39, P < 0.05), while CD68 expression in the invasive margin was significantly higher in the control group (control 98.9 ± 7.31, m-LV 28.2 ± 3.18, P < 0.05). These results suggest that the risk of metachronous liver metastasis could be well predicted by immunohistochemical staining of OPN in the central areas, and CD68 in the invasive margins of tumors.

Correlation of polymorphism of IL-8 and MMP-7 with occurrence and lymph node metastasis of early stage cervical cancer

The IL-8 and MMP-7 genes participate in the carcinogenesis of many malignancies, but the role of both genes in cervical cancer is not fully elucidated. The aim of this study was to determine the frequency of IL-8 and MMP-7 gene mutations and to assess their effects on the risk of early stage cervical cancer and lymph node metastasis. The clinical stage and histological grade of cervical cancer were also studied. The peripheral blood from the patients with early stage cervical cancers and normal controls was collected and the DNA was extracted. The incidence of IL-8 and MMP-7 gene mutations was assessed by using tetra-primer amplification refractory mutation system polymerase chain reaction (ARMS PCR) and restriction fragment length polymorphism (RFLP). The data were statistically analyzed by x2 test. The results showed that: (1) The genotype frequency of IL-8 -251AT and TT was significantly higher in the cervical cancer group than in the normal control group (OR=2.290 and 2.619 respectively, P=0.001), and it was also higher in the lymphatic metastasis group than that without metastasis (OR=2.917, P=0.035); (2) The frequency of MMP-7 -181G/G genotype was significantly higher in the cervical cancer group and in the lymphatic metastasis group (P<0.05); (3) The incidence of IL-8 mutation was two times higher in IIa cervical cancer group than in Ib1 and Ib2 cervical cancer group (P=0.006). For the MMP-7 gene, there was statistically significant difference in the incidence of mutation between the Ib1, Ib2 and the IIa (P=0.000); (4) Different histological types and different grades of cervical cancer had different incidence of mutations, statistically. It was suggested that there was significant difference in the genotype of IL-8 -251TT and MMP-7 -181GG polymorphism between the cervical cancer group and the lymph node metastasis group. Moreover, individuals with IL-8 T allele or MMP-7 G allele carriers were at significantly higher risk of cervical cancer, particularly the early (IIa) and medium, poorly differentiated cervical cancer (G2+G3).

Fibrin as a delivery system for therapeutic drugs and biomolecules

Fibrin is a natural biopolymer involved in the coagulation cascade. It acts as a reservoir for growth factors, cells, and enzymes during wound healing and provides a scaffold for the synthesis of extracellular matrix. Thus, the use of fibrin has expanded in recent years from traditional use as a sealant for surgical applications, to a tissue engineering scaffold capable of providing nature's cues for tissue regeneration. This paper reviews the advantageous biological aspects of fibrin, the history of the scaffold material, and its present role in the delivery of drugs, growth factors, cells, and gene vectors. Examples are given of studies where the structure and form of the scaffold have been manipulated for optimal release of the therapeutic agent, optimal cellular activity, and investigation into stem cell differentiation. It is evident from the body of literature presented that the benefits of fibrin are being exploited for a vast range of tissue engineering applications and that fibrin remains a key scaffold material for the delivery of drugs and biomolecules.

The lectin KM+ induces corneal epithelial wound healing in rabbits

Neutrophil influx is essential for corneal regeneration (Gan et al. 1999). KM+, a lectin from Artocarpus integrifolia, induces neutrophil migration (Santos-de-Oliveira et al. 1994). This study aims at investigating a possible effect of KM+ on corneal regeneration in rabbits. A 6.0-mm diameter area of debridement was created on the cornea of both eyes by mechanical scraping. The experimental eyes received drops of KM+ (2.5 microg/ml) every 2 h. The control eyes received buffer. The epithelial wounded areas of the lectin-treated and untreated eyes were stained with fluorescein, photographed and measured. The animals were killed 12 h (group 1, n = 5), 24 h (group 2, n = 10) and 48 h (group 3, n = 5) after the scraping. The corneas were analysed histologically (haematoxylin and eosin and immunostaining for proliferation cell nuclear antigen, p63, vascular endothelial growth factor, c-Met and laminin). No significant differences were found at the epithelial gap between treated and control eyes in the group 1. However, the number of neutrophils in the wounded area was significantly higher in treated eyes in this group. Three control and seven treated eyes were healed completely and only rare neutrophils persisted in the corneal stroma in group 2. No morphological distinction was observed between treated and control eyes in group 3. In treated corneas of group 2, there was an increase in immunostaining of factors involved in corneal healing compared to controls. Thus, topical application of KM+ may facilitate corneal epithelial wound healing in rabbits by means of a mechanism that involves increased influx of neutrophils into the wounded area induced by the lectin.

Hair cell regeneration: the identities of progenitor cells, potential triggers and instructive cues

Hair cells are produced and accumulate in the ears of fish and amphibians as they grow during postembryonic life; hair cell regeneration occurs in lateral line organs in those groups and in the cochlea in birds. Continuous time-lapse microscopy has directly demonstrated that supporting cells divide to give rise to hair cells during regeneration in lateral line neuromasts. Supporting cells also appear to give rise to hair cells during regeneration in the avian ear, but additional cell types have been proposed as hair cell progenitors. Alternative interpretations of current evidence are discussed in relation to the possibility that supporting cells may be the common progenitor in all cases of hair cell regeneration. The regenerative proliferation of hair cells in birds occurs in populations of cells that are mitotically quiescent in undamaged ears. Evidence suggests that the extrusion of damaged hair cells and the breaking of intercellular junctional adhesions may be a trigger for regenerative proliferation. The potential triggering influence of phagocytes is also discussed. The differentiation of replacement cells during regeneration in the cochlea may be regulated by surface interactions between cells. A model that could account for the reconstitution of the mosaic pattern of hair cells and supporting cells is proposed.

Fibroblast differentiation in wound healing and fibrosis

The contraction of granulation tissue from skin wounds was first described in the 1960s. Later it was discovered that during tissue repair, fibroblasts undergo a change in phenotype from their normal relatively quiescent state in which they are involved in slow turnover of the extracellular matrix, to a proliferative and contractile phenotype termed myofibroblasts. These cells show some of the phenotypic characteristics of smooth muscle cells and have been shown to contract in vitro. In the 1990s, a number of researchers in different fields showed that myofibroblasts are present during tissue repair or response to injury in a variety of other tissues, including the liver, kidney, and lung. During normal repair processes, the myofibroblastic cells are lost as repair resolves to form a scar. This cell loss is via apoptosis. In pathological fibroses, myofibroblasts persist in the tissue and are responsible for fibrosis via increased matrix synthesis and for contraction of the tissue. In many cases this expansion of the extracellular matrix impedes normal function of the organ. For this reason much interest has centered on the derivation of myofibroblasts and the factors that influence their differentiation, proliferation, extracellular matrix synthesis, and survival. Further understanding of how fibroblast differentiation and myofibroblast phenotype is controlled may provide valuable insights into future therapies that can control fibrosis and scarring.

Upregulation of Basic Fibroblast Growth Factor in Human Periapical Lesions

Basic fibroblast growth factor is one of a class of heparin-binding growth factors that stimulates endothelial cell proliferation and migration in vitro and angiogenesis in vivo. The purpose of this study was to investigate the expression of basic fibroblast growth factor in chronic periapical lesions of endodontic origin. Ten chronic inflammatory periapical lesions were examined using immunohistochemical staining. The experimental control group consisted of four specimens of uninflamed periodontal ligament tissue. Two independent observers graded the staining intensity for basic fibroblast growth factor. An immunopositive, cytoplasmic, and nuclear reaction for basic fibroblast growth factor, with varying degrees of upregulation was observed in all 10 chronic periapical lesions. We speculate that the formation of granulation tissue and the activation of epithelial cell rests in chronical apical lesions might be associated with a local rise in the tissue level of basic fibroblast growth factor. Therefore, this growth factor could play an important role in the pathogenesis of chronic apical periodontitis and periapical cysts.

Fibroblast growth factor 2 and transforming growth factor beta1 synergism in human bronchial smooth muscle cell proliferation

Bronchial smooth muscle cell (BSMC) hyperplasia is a typical feature of airway remodeling and contributes to airway obstruction and hyperresponsiveness in asthma. Fibroblast growth factor 2 (FGF-2) and transforming growth factor beta1 (TGF-beta1) are sequentially upregulated in asthmatic airways after allergic challenge. Whereas FGF-2 induces BSMC proliferation, the mitogenic effect of TGF-beta1 remains controversial, and the effect of sequential FGF-2 and TGF-beta1 co-stimulation on BSMC proliferation is unknown. This study aimed to assess the individual and sequential cooperative effects of FGF-2 and TGF-beta1 on human BSMC proliferation and define the underlying mechanisms. Mitogenic response was measured using crystal violet staining and [3H]-thymidine incorporation. Steady-state mRNA and protein levels were measured by semiquantitative RT-PCR, Western blot, and ELISA, respectively. TGF-beta1 (0.1-20 ng/ml) alone had no effect on BSMC proliferation, but increased the proliferative effect of FGF-2 (2 ng/ml) in a concentration-dependent manner (up to 6-fold). Two distinct platelet-derived growth factor receptor (PDGFR) inhibitors, AG1296 and Inhibitor III, as well as a neutralizing Ab against PDGFRalpha, partially blocked the synergism between these two growth factors. In this regard, TGF-beta1 increased PDGF-A and PDGF-C mRNA expression as well as PDGF-AA protein expression. Moreover, FGF-2 pretreatment increased the mRNA and protein expression of PDGFRalpha and the proliferative effect of exogenous PDGF-AA (140%). Our data suggest that FGF-2 and TGF-beta1 synergize in BSMC proliferation and that this synergism is partially mediated by a PDGF loop, where FGF-2 and TGF-beta1 upregulate the receptor (PDGFRalpha) and the ligands (PDGF-AA and PDGF-CC), respectively. This powerful synergistic effect may thus contribute to the hyperplastic phenotype of BSMC in remodeled asthmatic airways.

Evaluation of tumor angiogenesis measured with microvessel density (MVD) as a prognostic indicator in nasopharyngeal carcinoma: Results of RTOG 9505

PURPOSE

The objective of this study was to evaluate tumor angiogenesis as measured by microvessel density (MVD) as an independent prognostic factor in patients with nasopharyngeal carcinoma (NPC) treated with radiotherapy alone.

METHODS AND MATERIALS

Eligible patients included those with NPC treated with radiotherapy. Paraffin blocks of the primary tumor had a hematoxylin and eosin-stained section prepared at the block face. One representative section for tumor was stained for factor VIII-related antigen using a standard immunoperoxidase staining technique. MVD was determined by light microscopy in areas of invasive tumor containing the highest numbers of capillaries and microvessels per area. Individual microvessel counts were made on a 200x field within the area of most intense tumor neovascularization. Results were expressed as the highest number of microvessels identified within any single 200x field. Using a breakpoint of MVD <60 vs. > or =60, the distributions between the two MVD groups were compared by the method of Gray. Overall survival rates were estimated by the Kaplan-Meier method and compared by the log-rank test. A multivariate Cox proportional hazard model was employed to examine the relationship between MVD and disease outcomes while adjusting for other concomitant variables.

RESULTS

One hundred sixty-six were eligible, of whom 123 had values determined for MVD. The MVD values ranged from 9 to 243 with a median of 70. In the multivariate analysis of overall survival, distant metastases, and local-regional failure, MVD did not significantly improve the model containing T stage, N stage, age, radiation dose, and World Health Organization class.

CONCLUSIONS

We found no significant differences in overall survival, time to distant metastasis, or time to local-regional failure using a breakpoint of MVD <60 vs. MVD > or =60. The study was perhaps limited by the small size of the NPC samples.

Fibroblast growth factor/fibroblast growth factor receptor system in angiogenesis

Fibroblast growth factors (FGFs) are a family of heparin-binding growth factors. FGFs exert their pro-angiogenic activity by interacting with various endothelial cell surface receptors, including tyrosine kinase receptors, heparan-sulfate proteoglycans, and integrins. Their activity is modulated by a variety of free and extracellular matrix-associated molecules. Also, the cross-talk among FGFs, vascular endothelial growth factors (VEGFs), and inflammatory cytokines/chemokines may play a role in the modulation of blood vessel growth in different pathological conditions, including cancer. Indeed, several experimental evidences point to a role for FGFs in tumor growth and angiogenesis. This review will focus on the relevance of the FGF/FGF receptor system in adult angiogenesis and its contribution to tumor vascularization.

Ghrelin inhibits FGF-2-mediated angiogenesis in vitro and in vivo

Recent evidence indicates that ghrelin, an endogenous ligand of the growth hormone secretagogue receptor (GHS-R), is highly expressed in the cardiovascular system, and in this study we addressed the possibility that ghrelin may affect angiogenesis in vitro and in vivo. Reverse transcription-polymerase chain reaction showed that human umbilical vein endothelial cells (HUVECs) express ghrelin and GHS-R mRNAs. Ghrelin inhibited FGF-2-induced proliferation of HUVECs cultured in vitro, the maximal effective concentration being 10(-8) M, and this effect was annulled by the GHS-R antagonist D-Lys3-growth hormone releasing peptide-6. FGF-2 stimulated HUVEC cultured on Matrigel to form capillary-like structures, and ghrelin (10(-8) M) suppressed this effect. In the chick embryo chorioallantoic membrane in vivo assay, FGF-2 induced a strong angiogenic response, which was counteracted by ghrelin (500 ng). Taken together, these findings suggest that ghrelin acts as an angiostatic molecule and indicate that its activity is comparable to that of a well-known angiostatic agent, i.e., vinblastine. The antiangiogenic activity of ghrelin deserves further investigations, alone or together with other antiangiogenic agents, for the treatment of pathological conditions characterized by enhanced angiogenesis.

Mucosal concentration of basic fibroblast growth factor in the healing process in human giant gastric ulcers

OBJECTIVES

Basic fibroblast growth factor (bFGF) is a key factor in the healing of human and experimental peptic ulcers, but the behavior of bFGF in human giant gastric ulcer remains to be determined. We determined the bFGF content in the rim of giant ulcers (bFGF rim) and in non-ulcerated mucosa located opposite the ulcer (bFGF opposite) before and during treatment.

METHODS

Biopsy specimens were endoscopically obtained from 31 patients with giant gastric ulcers and 17 patients with small ulcers before and 2, 4 and 8 weeks after treatment. The bFGF concentrations in the specimens were measured using a sandwich enzyme immunoassay.

RESULTS

Before treatment, the bFGF rim and bFGF opposite concentrations were not associated with ulcer size. The bFGF rim concentration before treatment in the rapid healing group was higher than that in the slow healing group, but no significant difference in bFGF opposite concentrations were found between the two groups. The bFGF rim concentration in the rapid healing patients decreased during treatment, while the slow healing patients showed an inverse response. The bFGF opposite concentration did not change during treatment and bFGF rim concentrations in Helicobacter pylori-positive stomachs were significantly lower than those in H. pylori-negative stomachs.

CONCLUSIONS

The bFGF rim concentration is not involved in the formation of giant gastric ulcers in humans. However, the bFGF rim concentration does appear to promote healing. The bFGF opposite concentration is not related to either the formation or healing of giant gastric ulcers.

Significance of monocyte chemotactic protein-1 and thymidine phosphorylase in angiogenesis of human cardiac myxoma

Angiogenesis is indispensable to tumor development and proliferation. The aim of this study was to investigate whether the expression of monocyte chemotactic protein-1 (MCP-1) and of thymidine phosphorylase (TP) correlates with the angiogenesis and clinicopathologic features in cardiac myxoma. Paraffin-embedded specimens of 17 resected cardiac myxomas were immunohistochemically stained for MCP-1, CC chemokine receptor-2 (CCR-2), TP, CD31, and CD68. Correlations among MCP-1 expression, TP expression, microvessel count (determined by CD31 staining), macrophage count (determined by CD68 staining), and the clinicopathologic features of the patients were analyzed statistically. Immunohistochemical analysis revealed that MCP-1 and TP were expressed in myxoma cells, as well as in stromal cells such as infiltrating cells, fibroblast-like cells and endothelial cells. CCR-2 was abundantly expressed in stromal infiltrating cells in all myxomas and occasionally in the endothelial cells. In the tumor stroma, the major source of MCP-1, TP and CCR-2 was macrophages, and the sites of positive staining for MCP-1, TP and CCR-2 matched in most of the myxomas. Statistical analysis revealed that the proportions of MCP-1-positive myxoma and stromal cells, and TP-positive myxoma and stromal cells significantly correlated with increased microvessel count. The proportions of MCP-1-positive myxoma and stromal cells significantly correlated with the proportion of TP-positive stromal cells. The mean microvessel count in myxomas with both high tumor and high stromal MCP-1 or TP expression was significantly higher than that in myxomas with low tumor and low stromal MCP-1 or TP expression. Small tumors (< or =55 mm in diameter) exhibited high MCP-1 or TP expression, and the microvessel count in small tumors was significantly higher than in large myxomas. Although the difference was not significant, myxomas with both high tumor and high stromal MCP-1 expression had a higher macrophage count than other myxomas. These results indicate that in cardiac myxoma, MCP-1 and TP may be regarded as important angiogenic signals accompanying growth.

Inflammation. 1: Its role in the healing of acute wounds

The inflammatory response is an essential part of the wound-healing process. This article discusses inflammation in acute wounds and the part played by the migration of cells including neutrophils, macrophages and T-lymphocytes.

Clinical implications of expression of interleukin-8 related to myometrial invasion with angiogenesis in uterine endometrial cancers

BACKGROUND

Angiogenesis is essential for development, growth and advancement of solid tumors. The tumor-associated macrophage has been recognized among inflammatory cells as a candidate for supplying tumor angiogenic factors. Interleukin (IL)-8 is assumed to be a macrophage-derived mediator of angiogenesis. This prompted us to study the clinical implications of macrophage-derived angiogenesis in uterine endometrial cancers.

PATIENTS AND METHODS

Sixty patients underwent curative resection for uterine endometrial cancers. The patient prognosis was analyzed with a 48 month survival rate after curative resection. In tissue of uterine endometrial cancers, the levels of IL-1alpha, IL-1beta, tumor necrosis factor-alpha, IL-8, basic fibroblast growth factor, vascular endothelial growth factor and platelet-derived endothelial cell growth factor were determined by enzyme immunoassay, and the localization and counts of microvessels and macrophages were determined by immunohistochemistry.

RESULTS

There was a significant correlation between microvessel counts and IL-8 levels and between infiltrated macrophage counts and IL-8 levels in uterine endometrial cancers. Immunohistochemical staining revealed that the localization of IL-8 was similar to that of CD68 for macrophages. IL-8 levels were significantly increased during myometrial invasion from stage Ia to stages Ib through IV.

CONCLUSIONS

IL-8 might act as an angiogenic switch in myometrial invasion in stage I uterine endometrial cancers. Furthermore, IL-8 supplied from infiltrated macrophages within and around the tumor might not be a prognostic indicator of advancement, but may be associated with myometrial invasion in uterine endometrial cancers.

Age-related changes in wound healing

Evidence for age-related effects on wound healing have been derived for the most part from empirical observations without adjustment for confounders other than age. Age-related changes in the structure and function of the skin do occur. Some of these changes result from chronic solar radiation exposure rather than chronological age per se. The tensile strength of wounds, accumulation of wound healing factors and rate of wound closure have all been examined in relation to chronological aging. However, the clinical impact of these changes in acute wound healing appears to be small. Poor healing in chronic wounds is more often related to comorbid conditions rather than age alone. Since the majority of these chronic wounds occur in elderly populations, this has contributed to the conclusion that aging itself may influence healing. Progress in understanding the role that growth factors play in wound healing and the ability to synthesise adequate quantities of these factors for clinical use has led to clinical trials evaluating their use in wound healing. The results of these studies, with the possible exception of those in diabetic wounds, have been disappointing. Insight into the wound healing process indicates that growth factors interact during wound healing in a sequential and orderly process. Improved wound healing may require different clinical designs or the use of these factors in a precisely timed sequential administration.

Photoreceptor rescue after low-dose intravitreal IL-1beta injection in the RCS rat

Photoreceptor survival in the dystrophic rat was evaluated following administration of IL-1beta at dosages much lower than those used previously for this purpose. Royal College of Surgeons rats (pink-eyed, pigmented, or non-dystrophic) received 1 microl intravitreal injections of murine recombinant IL-1beta (0.5, 2, or 5 microg ml(-1); at 3 or 4 weeks of age). Eyes were harvested 4 weeks later and outer nuclear layer profiles counted. Additional animals received intravitreal basic fibroblast growth factor (1000 microg ml(-1)), or vehicle alone. Others were treated with IL-1beta to evaluate the inflammatory response (CD45+ profiles) or visual function via opto-kinetic response. IL-1beta was associated with photoreceptor rescue that was both dose-dependent and comparable to that seen following high-dose basic fibroblast growth factor. Significant anatomical rescue relative to controls was seen in both pink-eyed and pigmented strains, although the degree and distribution varied between strains. Functional rescue was confirmed by opto-kinetic response using the pigmented strain. At 5 microg ml(-1), IL-1beta resulted in numerous CD45+ profiles within the retina and vitreous. Infiltration peaked at 48 hr and was minimal at 4 weeks, without dysplastic sequelae. IL-1beta therefore induces visually significant photoreceptor rescue in a potent, dose-dependent manner that need not entail cytoarchitectural disruption. This is consistent with the known association between injury and rescue in the rat retina. Neuroprotection may be a general, if under-appreciated, consequence of inflammatory cascade activation.

Understanding the final stages of wound contraction

Much research has been undertaken to improve our understanding of the processes of wound contraction. This article, the second in a two-part series, focuses on granulation tissue modulation.

Immunohistochemical localization of Betacellulin, a member of epidermal growth factor family, in atherosclerotic plaques of human aorta

Betacellulin (BTC), a new member of the EGF family, has been reported to be a potent mitogen for rat vascular smooth muscle cells (SMCs). BTC mRNA is known to be expressed in several human organs. However, the localization of BTC in human vascular tissues has not yet been clarified. We investigated whether or not BTC protein is involved in the pathogenesis of human atherosclerosis. Recombinant human BTC showed a mitogenic activity on cultured human aortic SMCs by measuring [3H]thymidine incorporation. The immunohistochemical localization of BTC, SMCs, macrophages, EGF receptors and ErbB4 was examined in autopsied human aortas. BTC was detected in both intimal and medial SMCs of the aortic wall. The percentage of BTC-positive medial SMCs in early types of atherosclerotic lesions decreased with age, but in adult, it was significantly higher in advanced types than in early types of atherosclerotic lesions. BTC-positive SMCs were predominantly localized in the medial side of the intima. Furthermore, numerous BTC-positive SMCs and macrophages were observed around the core lesion of atherosclerotic plaques. Receptors for BTC, EGF receptor and ErbB4, were expressed on SMCs, suggesting that BTC is associated with EGF receptor family-mediated signaling. BTC is produced in human aortic tissue and might play important roles in atherogenesis.

Examining new models for the study of autocrine and paracrine mechanisms of angiogenesis through FGF2-transfected endothelial and tumour cells

Angiogenesis is the process of generating new capillary blood vessels. Uncontrolled endothelial cell proliferation is observed in tumour neovascularization. Several growth factors and cytokines have been shown to stimulate endothelial cell proliferation in vitro and in vivo and among them FGF2 was one of the first to be characterised. FGF2 is a Mr 18,000 heparin-binding cationic polypeptide that induces proliferation, migration, and protease production in endothelial cells in culture and neovascularization in vivo. FGF2 interacts with endothelial cells through two distinct classes of receptors, the high affinity tyrosine-kinase receptors (FGFRs) and low affinity heparan sulfate proteoglycans (HSPGs) present on the cell surface and in the extracellular matrix. Besides experimental evidence for paracrine mode of action for FGF2, some observations raise the hypothesis that FGF2 may also play an autocrine role in endothelial cells. FGF2 may therefore represent a target for anti-angiogenic therapies. In order to assess the angiostatic potential of different classes of compounds, novel experimental models have been developed based on the autocrine and/or the paracrine capacity of FGF2.

Differential expression of fibroblast growth factor-2 and fibroblast growth factor receptor 1 in a scarring and nonscarring model of CNS injury in the rat

Injury to the adult brain results in abortive axon regeneration and the deposition of a dense fibrous glial scar. Therapeutic strategies to promote postinjury axon regeneration are likely to require antiscarring strategies. In neonatal brain wounds, scar material is not laid down and axons grow across the lesion site, either by de novo growth or regeneration. To achieve the therapeutic goal of recapitulating the nonscarring neonatal response in the injured adult, an understanding of how ontogenic differences in scarring reflect developmental diversities in the trophic response to injury is required. Fibrobast growth factor-2 (FGF-2) expression is developmentally regulated and has been implicated as a regulator of the wounding response of the adult rat central nervous system. We have investigated the expression of FGF-2 and fibroblast growth factor receptor 1 (FGFR1) after penetrating lesions to the cerebral cortex of 5 days post partum (dpp) (nonscarring) and 16 dpp and adult (scarring) rats. In situ hybridization, immunohistochemistry and Western blotting showed robust and sustained increases in FGF-2 and FGFR1 mRNA and protein in reactive astrocytes around the lesion in scarring rats, a response that was attenuated substantially in the nonscarring neonate. These results demonstrate that changes in astrocyte FGF-2 and FGFR1 expression are coincident with the establishment of a mature pattern of glial scarring after injury in the maturing central nervous system, but it is premature to infer a causal relationship without further experiments.

Engineering, expression, and renaturation of a collagen-targeted human bFGF fusion protein

Basic fibroblast growth factor (bFGF) is a potent in vitro mitogen for capillary endothelial cells, stimulates angiogenesis in vivo, and may participate in tissue repair. Basic FGF is found in abundance in tissues such as brain, kidney and cartilage. This study reports the expression, purification, and renaturation of a biologically active human basic fibroblast growth factor fusion protein (hbFGF-F1) from Escherichia coli. A prokaryotic expression vector was engineered to produce a tripartite fusion protein consisting of (i) a purification tag, (ii) a protease-sensitive linker/collagen-binding domain, and (iii) cDNA sequence encoding the active fragment of hbFGF. The expressed hbFGF-F1 and hbFGF-F2 (it contains a collagen-binding domain), located in inclusion bodies, were solubilized with 6 M guanidine-HCl and renatured using a glutathione redox system and protracted dialysis under various experimental conditions. The purification of the recombinant proteins was achieved by binding the His-tag of the fusion protein on a Ni-NTA metal chelate column. The biological activity of the recombinant growth factors was demonstrated by their ability to stimulate proliferation of human vein endothelial cells (HVEC), monitored by [3H]-thymidine incorporation, where commercial recombinant human bFGF (rhbFGF) served as a positive control. Purified rhbFGF-F1 and rhbFGF-F2 constructs exhibited proliferative activity comparable to commercial rhbFGF. Binding of the renatured hbFGF-F2 fusion protein to collagen was demonstrated by stable binding on a collagen-conjugated Sephadex-G15 column. The high affinity binding was also demonstrated by the binding of [3H]-collagen to the rhbFGF-F2 protein immobilized on a Ni-NTA column. The rhbFGF-F2 fusion protein bound to collagen coated surfaces with high affinity but exhibited comparatively lower biological activity than the fusion protein in solution, suggesting a potentially latent configuration. Taken together, these results demonstrate that biologically active rhbFGF fusion proteins can be recovered from transformed bacteria by oxidative refolding; thus, providing a means for its high-yield production, purification, and renaturation from microorganisms. Furthermore, we demonstrate that the auxiliary collagen-binding domain effectively targets the recombinant growth factor to type I collagen. The clinical effect of rhbFGF-F2 on wound healing is also studied in streptozotocin-induced diabetic rats and evaluated by histological examination comparing with rhbFGF-F1 and commercial bFGF effects. The highly beneficial effects of rhbFGF-F2 on wound healing is suggested to be due to its extremely potent angiogenesis and granulation tissue formation activities, leading to a rapid reepithelialization of the wound. Topical application of rhbFGF-F2 mixed with type I collagen is a more effective method in accelerating closure of full-thickness excisional skin-wound in diabetic rats when compared with the fusion protein alone or commercial hbFGF at the same doses. These studies advance the technology necessary to generate large quantities of targeted bFGF fusion proteins as well as to develop new strategies for specific biomedical applications.

Production of a recombinant human basic fibroblast growth factor with a collagen binding domain

Basic fibroblast growth factor (bFGF) is a potent in vitro mitogen for capillary endothelial cells, stimulates angiogenesis in vivo, and may participate in tissue repair. Basic FGF is found in abundance in tissues such as brain, kidney, and cartilage. This study reports the expression, purification, and renaturation of a biologically active human basic fibroblast growth factor fusion protein (hbFGF-F1) from Escherichia coli. A prokaryotic expression vector was engineered to produce a tripartite fusion protein consisting of a purification tag, a protease-sensitive linker and collagen binding domain, and a cDNA sequence encoding the active fragment of hbFGF. The expressed hbFGF-F1 and hbFGF-F2 (it contains the collagen binding domain), located in inclusion bodies, were solubilized with 6 M guanidine-HCl and renatured by a glutathione redox system and protracted dialysis under various experimental conditions. The purification of the recombinant proteins was achieved by binding the His-tag of the fusion protein on a nickel-nitrilotriacetic acid metal chelate column. The biological activity of the recombinant growth factor was demonstrated by its ability to stimulate proliferation of human vein endothelial cells, monitored by [3H]thymidine incorporation, where commercial recombinant human bFGF (rhbFGF) served as a positive control. Purified rhbFGF-F1 and rhbFGF-F2 constructs exhibited proliferative activity comparable to commercial rhbFGF. The high-affinity binding was demonstrated by the binding of [3H]collagen to the rhbFGF-F2 protein immobilized on a Ni-nitrilotriacetic acid column. The rhbFGF-F2 fusion protein bound to collagen-coated surfaces with high affinity. Taken together, these results demonstrate that biologically active rhbFGF fusion proteins can be recovered from transformed bacteria by oxidative refolding; thus, providing a means for their high-yield production, purification, and renaturation from microorganisms. Furthermore, we demonstrate that the auxiliary collagen binding domain effectively targets the recombinant growth factor to type I collagen. These studies advance the technology necessary to generate large quantities of targeted bFGF fusion proteins for specific biomedical applications.

Effect of hypercholesterolemia on the sequential changes of apoptosis and proliferation after balloon injury to rabbit iliac artery

To evaluate the effect of hypercholesterolemia on apoptosis and proliferation after vascular injury, iliac arteries of hypercholesterolemic (HC) and normocholesterolemic (NC) rabbits were examined after balloon injury using TUNEL, immunohistochemical staining of PCNA, macrophages, smooth muscle actin and p53. In media, apoptosis occurred massively early after injury and then decreased. HC did not affect this early post-injury apoptosis but significantly increased apoptosis 14 days later (D14). Immediate apoptosis in media was followed by active proliferation. HC sustained a high activity of proliferation until D14. The changes of immunoreactivity to p53 over the same 14 day period parallel that of apoptosis. In intima, where cells were scarce initially, proliferative activity reached a peak at D7 and then decreased. HC significantly enhanced proliferation at D14. In intima proliferation was accompanied by a later low-level apoptosis. HC significantly enhanced this low-level apoptosis at D14. These effects of HC resulted in significantly increased areas of intima and media. The fundamental difference between HC and NC was the infiltration of macrophages in HC. In conclusion, balloon injury induces early massive p53-associated apoptosis followed by proliferation in media, whereas in intima, it induces active proliferation followed by a low-level apoptosis. Hypercholesterolemia does not affect the early post-injury apoptosis but enhances proliferation and low-level apoptosis at a later stage, which in turn results in intimal and medial hyperplasia.

The detection and comparison of angiogenesis-associated factors in pyogenic granuloma by immunohistochemistry

BACKGROUND

Pyogenic granuloma is a benign inflammatory lesion demonstrating obvious activity of angiogenesis. Female steroid hormones are believed to play important roles in the etiology because the lesion is frequently found in females with high levels of sex hormones. Few molecular mechanisms of the pathogenesis have been proposed and proven. The purpose of this study was to detect and compare the expression of angiogenesis-associated factors among healthy gingiva, gingiva from periodontitis, and pyogenic granuloma to clarify the pathogenesis of pyogenic granuloma.

METHODS

Fifteen specimens were collected from each of 3 groups of gingiva (healthy gingiva, periodontitis, and pyogenic granuloma). The subjects were age and gender matched. The specimens were processed for immunohistochemistry to detect and compare the expression of 2 angiogenesis enhancers, i.e., vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), 2 angiogenesis inhibitors, i.e., angiostatin and thrombospondin-1 (TSP-1), and estrogen receptor (ER). Using the subject as the unit of statistical analysis, either analysis of variance or chi-square analysis was employed to show the statistically significant difference at a level P <0.05.

RESULTS

The pyogenic granuloma group expressed significantly more VEGF and bFGF than healthy gingiva and periodontitis. The positive staining of VEGF was mostly localized in the cytoplasm of macrophages and fibroblasts while that of bFGF was in the extracellular matrix of lamina propria. Angiostatin was expressed significantly less in pyogenic granuloma than the other 2 groups and was mostly localized in the nuclei of endothelial cells and epithelial cells. There was no significant difference in the expression of TSP-1 and ER among the 3 groups.

CONCLUSIONS

The results of this research suggest that the etiology of pyogenic granuloma is due to the imbalance between angiogenesis enhancers and inhibitors. Whether and how the angiogenesis-associated factors are regulated by female steroid hormones remain to be answered.

Inducible expression of the cell surface heparan sulfate proteoglycan syndecan-2 (fibroglycan) on human activated macrophages can regulate fibroblast growth factor action

Monocyte/macrophages play important roles in regulating tissue growth and angiogenesis through the controlled release of heparin-binding growth factors such as fibroblast growth factor (FGF), vascular endothelial growth factor, and heparin binding epidermal growth factor. The action of these potent growth mediators is known to be regulated by adsorption to heparan sulfate proteoglycans (HSPGs) on the surface and within the extracellular matrix of other neighboring cells, which respectively promote or restrict interactions with their signal-transducing receptors on target cells. Here we report on the nature of HSPGs inducibly expressed on the surface of macrophages that confer these cells with the capacity to regulate endogenous growth factor activity. We reveal that activated human macrophages express only a single major 48-kDa cell surface HSPG, syndecan-2 (fibroglycan) as the result of de novo RNA and protein synthesis. In addition, we demonstrate this macrophage HSPG selectively binds the macrophage-derived growth factors FGF-2, vascular endothelial growth factor and heparin binding EGF and can present FGF-2 in a form that transactivates receptor-bearing BaF32 cells. These results define a novel and unique proteoglycan profile for macrophages and imply a key role for syndecan-2 in the delivery of sequestered growth factors by inflammatory macrophages for productive binding to their appropriate target cells in vivo.

Inhibition of human arterial smooth muscle cell growth by human monocyte/macrophages: a co-culture study

Monocyte/macrophages produce a variety of substances which may influence the function of smooth muscle cells (SMC). During atherogenesis, macrophages are thought to modulate SMC migration, proliferation and synthesis of extracellular matrix. Such modulation is the balance between stimulatory and inhibitory influences. Thus, for example, our earlier studies have shown that macrophages not only secrete mitogens, but also produce small molecular weight inhibitors of SMC proliferation. In the present study, we have used a co-culture system in which human monocyte/macrophages were separated from human arterial SMC (hSMC) by a filter with the optional addition of a 12 kDa cut-off dialysis membrane, in order to assess their effect on hSMC growth. We have found that human peripheral blood-derived monocytes produced a substance of < 12 kDa that inhibited hSMC growth in the co-culture system. The monocyte-derived factor causing this effect was completely blocked by indomethacin, indicating that growth-inhibitory factors produced by the monocytes were cyclooxygenase products. We have shown that PGE1 and PGE2 inhibit hSMC growth, making them likely candidates for the effector molecules released from monocytes in our co-culture system.

Understanding and controlling the scarring response: the contribution of histology and microscopy

In response to injury, the body usually initiates a full and swift wound healing response resulting in reconstructed, repaired tissue. In certain instances, due to a variety of factors, this may not happen, an example being chronic granulating venous leg ulcers. At the other extreme, the wound may heal excessively, producing disabling hypertrophic scarring such as can occur following large, deep burn injuries. Our group is interested in the surgical treatment of the eye disease glaucoma. As will be explained, the successful surgical treatment of this disease depends on a reduced scarring response at the end of wound healing. The purpose of this article is to give an overview of our microscopic and histological experimental work which has furthered our understanding of tissue repair, particularly the scarring response and its potential modification for successful glaucoma surgery.