Platelet-derived growth factor and vascular endothelial growth factor expression in disc herniation tissue: an immunohistochemical study

Angiogenesis is essential in tissue growth and regeneration. There are several factors that are able to stimulate vascular endothelial cell growth, including platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF). Disc herniation tissue (DHT) contains vascular ingrowth, which promotes granulation tissue formation. In this study we observed 50 disc herniations for PDGF and VEGF immunoreactivity. PDGF immunopositivity was detected in 38 samples (78%). In 28 samples (56%) there were PDGF immunopositive capillaries, PDGF immunopositive disc cells were detected in 19 samples (38%) and PDGF immunopositive fibroblasts in 6 DHT samples (12%). VEGF immunopositive capillaries were identified in 44 DHT samples (88%). For neither growth factor was immunopositivity dependent on preoperative radicular pain duration. In extrusions (n = 25) VEGF immunopositive capillaries were detected in 23 samples (92%) and PDGF immunopositivity in 21 samples (84%). PDGF immunopositivity was more commonly associated with capillaries than with nuclei of disc cells. In sequesters (n = 20) VEGF immunopositive capillaries were identified in all samples and PDGF immunopositivity in 16 (80%). As in extrusions, PDGF immunoreaction was more prevalent in capillaries than in disc cells. Patient age did not relate to VEGF expression. In all age groups it was higher than 80%. Thus capillaries in disc herniation tissue are evidently newly formed and our results demonstrate that PDGF and VEGF participate in the neovascularization process. The presence of PDGF in fibroblasts and in disc cells suggests that this growth factor regulates the function of these cells, possibly the proliferation of the cells and the production of extracellular matrix components.     

VEGF inhibits PDGF-stimulated calcium signaling independent of phospholipase C and protein kinase C

INTRODUCTION: Despite advances in both open and endovascular techniques for treatment of arterial occlusive disease, restenosis because of neointimal hyperplasia continues to be a major cause of graft failure and restenosis. This phenomenon has been attributed to vascular smooth muscle cell (VSMC) activation by several potent mitogens including platelet derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) released at the site of injury. PDGF is known to stimulate calcium influx in VSMC that has been shown to be critical for VSMC migration and proliferation. We have previously shown that VEGF inhibits PDGF-stimulated VSMC proliferation. The objective of this set of experiments was to investigate whether VEGF modulated PDGF-stimulated Ca2+ influx in VSMC. MATERIALS AND METHODS: Primary cultured human aortic SMC were grown to subconfluency and assigned to the following groups: no stimulation, stimulation with PDGF-BB (20 ng/ml), stimulation with VEGF165 (40 ng/ml), or a combination of PDGF-BB + VEGF165. Ca2+ influx was measured using a Fura-2 fluorescence assay. The intracellular Ca2+ fraction was assayed with the Fura-2 assay by using Ca2+-free media. Phospholipase Cgamma1 (PLCgamma1), protein kinase C (PKC), and Akt phosphorylation was assessed with standard immunoblotting techniques at 1, 5, and 10 min time points. Ca2+-calmodulin kinase II (CaMKII) activity was extrapolated from the phosphorylation of Phospholamban B (PLB), a well-known protein substrate, at 1, 5, and 10 min time points. RESULTS: PDGF stimulation resulted in a 328 +/- 9 nm total calcium influx in VSMC. The combination of VEGF + PDGF resulted in a 273 +/- 21 nm total calcium influx, an amount significantly less than with PDGF alone (P < 0.04). PDGF stimulation resulted in a 72 +/- 35 nm intracellular calcium release. The addition of VEGF to PDGF resulted in an intracellular calcium release of only 15 +/- 11 nm, a significant decrease compared to PDGF alone (P < 0.01). The phosphorylation of PLCgamma1, PKC, and Akt was equivalent at 1, 5, and 10 min between the PDGF and the PDGF + VEGF treatment groups. There was an increase in CaMKII activity at 1 and 5 min time points in both the PDGF and PDGF + VEGF treatment groups suggesting that extracellular calcium influx is sufficient for CaMKII activation. CONCLUSION: VEGF inhibits PDGF-stimulated total calcium influx and, in particular, PDGF-stimulated intracellular calcium release in VSMC. The equivalent phosphorylation of PLCgamma1, PKC, and Akt suggests that the inhibitory mechanism by VEGF on calcium influx occurs downstream of these proximal mediators. The inhibition of intracellular calcium release did not inhibit CaMKII activity. VEGF may play an important role in modulating PDGF induced VSMC proliferation by specifically inhibiting intracellular calcium release in response to PDGF.     

Adipose‐Derived Stromal Vascular Fraction and Cultured Stromal Cells as Trophic Mediators for Tendon Healing

Adipose‐derived stromal vascular fraction (SVF) is a heterogeneous population of cells that yields a homogeneous population of plastic‐adherent adipose tissue‐derived stromal cells (ASC) when culture‐expanded. SVF and ASC have been used clinically to improve tendon healing, yet their mechanism of action is not fully elucidated. The objective of this study was to investigate the potential for ASC to act as trophic mediators for tendon healing. Flexor digitorum superficialis tendons and adipose tissue were harvested from adult horses to obtain SVF, ASC, and tenocytes. Growth factor gene expression was quantified in SVF and ASC in serial passages and growth factors were quantified in ASC‐conditioned medium (CM). Microchemotaxis assays were performed using ASC‐CM. Tenocytes were grown in co‐culture with autologous ASC or allogeneic SVF. Gene expression for insulin‐like growth factor 1 (IGF‐1), stromal cell‐derived factor‐1α (SDF‐1α), transforming growth factor‐β1 (TGF‐β1) and TGF‐β3 was significantly higher in SVF compared to ASC. Concentrations were significantly increased in ASC‐CM compared to controls for IGF‐1 (4‐fold) and SDF‐1α (6‐fold). Medium conditioned by ASC induced significant cell migration in a dose‐dependent manner. Gene expression for collagen types I and III, decorin, and cartilage oligomeric matrix protein was modestly, but significantly increased following co‐culture of tenocytes with autologous ASC. Our findings support the ability of SVF and ASC to act as trophic mediators in tendon healing, particularly through chemotaxis, which stands to critically impact the intrinsic healing response. In vivo studies to further delineate the potential for SVF and/or ASC to improve tendon healing are warranted. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1429–1439, 2019.     

Localization of Matrix Metalloproteinases, (MMPs) Their Tissue Inhibitors, and Vascular Endothelial Growth Factor (VEGF) in Growth Plates of Children and Adolescents Indicates a Role for MMPs in Human Postnatal Growth and Skeletal Maturation

Numerous studies have focused on the expression, regulation, and biological significance of matrix metalloproteinases (MMPs) in the growth plate. Findings in mouse knockout models and in vitro data from various species indicate that MMPs not only degrade extracellular matrix components but may regulate the activity of local growth factors. In this study we investigated the presence, distribution, and activity of various MMPs and inhibitors, tissue transglutaminase (tTG or TG2) and vascular endothelial growth factor (VEGF) in the human child and adolescent growth plates by means of immunohistochemistry and gelatin zymography. Tissue was derived during orthopedic surgery (epiphysiodesis) in two prepubertal and four pubertal patients.MMP-2 and MMP-14 were present in reserve cell chondrocytes. MMP-14 was the most prominent MMP within all zones of the growth plate including proliferating chondrocytes. MMP-1 and MMP-13 (collagenases 1 and 3), MMP-9 (gelatinases B), MMP-10, and MMP-11 (stromelysins) and VEGF were positive in hypertrophic chondrocytes and osteoblasts. MMP-2 showed the same expression pattern but was negative in osteoblasts. Osteoclasts stained positive for MMP-9, MMP-2, and TG2. Tissue inhibitor of MMP (TIMP)-1 was present in all zones of the growth plate, osteoblasts, and osteoclasts; TIMP-2 was found in hypertrophic chondrocytes and osteoblasts. In summary, the presence of MMPs, TIMPs, TG2, and VEGF in our study indicated that the MMPs are relevant in growth plate physiology during the postnatal period in humans. The specific location of MMP expression within the growth plate may be the basis for further studies on the role of MMPs in the local regulation of chondrocyte differentiation, proliferation, and ossification at the chondroosseus junction.     

VEGF与MMP-9在卵巢癌组织中的表达及与淋巴结浸润转移的相关性研究

目的探讨VEGF与MMP-9在卵巢癌组织中的表达,进一步探讨二者与淋巴结浸润转移的相关性与作用机制。方法采用免疫组织化学方法检测34例卵巢癌组织中VEGF、MMP-9的表达,并运用统计学方法对二者与卵巢癌的临床病理特征的关系进行对比分析。同期选择正常卵巢组织30例、卵巢良性肿瘤30例作对照。结果 VEGF、MMP-9在卵巢癌组织中阳性表达显著高于正常组织（P〈0.05）,VEGF、MMP-9的阳性表达与年龄、组织分化类型无相关性（P〉0.05）;VEGF、MMP-9在有淋巴结转移组织中的表达显著高于无淋巴结转移组织（P〈0.05）;VEGF和MMP-9在FIGO分期为Ⅲ~Ⅳ的组织中阳性表达显著高于Ⅰ~Ⅱ期组织（P〈0.05）。VEGF表达和MMP-9在卵巢组织中表达呈正相关（r=0.625,P〈0.05）。结论 VEGF、MMP-9均参与卵巢癌的发生和发展,二者高表达使肿瘤组织转移性和侵袭性显著增加。     

Expression patterns of matrix metalloproteinases and vascular endothelial growth factor during epiphyseal ossification.

In situ hybridization studies allowed for the localization of three MMPs and the angiogenic factor VEGF during secondary ossification. MMPs were widely expressed during ossification of the secondary center, whereas expression of VEGF was restricted to later stages. INTRODUCTION: The spatiotemporal expression patterns of the matrix metalloproteinases gelatinase-B (MMP-9), collagenase-3 (MMP-13), and membrane-type 1 metalloproteinase (MMP-14) and the angiogenic peptide vascular endothelial growth factor (VEGF) were studied during development of the proximal epiphysis of the rat tibia. MATERIALS AND METHODS: Cell expression was analyzed by in situ hybridization. Studies on osteoclastic activity, matrix mineralization, cell proliferation, and vascular progression were also performed. RESULTS: MMP-9, MMP-13, and MMP-14 were expressed in discrete perichondrial cells that gave way to sites of intrachondral canal formation. High expression levels for the three MMPs were found at the blind ends of advancing intrachondral canals and at the expanding borders of the marrow space. Signals for MMP-9 and MMP-13 were in close proximity but did not overlap, whereas MMP-14 was expressed in both MMP-9+ and MMP-13+ cells. VEGF was not expressed during formation of intrachondral vascular canals but was observed in hypertrophic chondrocytes during formation of the bone marrow cavity. CONCLUSIONS: Expression of MMPs and VEGF are constant events during development of the secondary ossification center. We propose that MMPs are involved in targeting proteolytic activity during epiphyseal development. VEGF is not expressed during early formation of vascular canals, but it may have a role in the formation of the bone marrow cavity.     

PERSPECTIVE ARTICLE: Growth factors and cytokines in wound healing

Wound healing is an evolutionarily conserved, complex, multicellular process that, in skin, aims at barrier restoration. This process involves the coordinated efforts of several cell types including keratinocytes, fibroblasts, endothelial cells, macrophages, and platelets. The migration, infiltration, proliferation, and differentiation of these cells will culminate in an inflammatory response, the formation of new tissue and ultimately wound closure. This complex process is executed and regulated by an equally complex signaling network involving numerous growth factors, cytokines and chemokines. Of particular importance is the epidermal growth factor (EGF) family, transforming growth factor beta (TGF‐β) family, fibroblast growth factor (FGF) family, vascular endothelial growth factor (VEGF), granulocyte macrophage colony stimulating factor (GM‐CSF), platelet‐derived growth factor (PDGF), connective tissue growth factor (CTGF), interleukin (IL) family, and tumor nerosis factor‐α family. Currently, patients are treated by three growth factors: PDGF‐BB, bFGF, and GM‐CSF. Only PDGF‐BB has successfully completed randomized clinical trials in the Unites States. With gene therapy now in clinical trial and the discovery of biodegradable polymers, fibrin mesh, and human collagen serving as potential delivery systems other growth factors may soon be available to patients. This review will focus on the specific roles of these growth factors and cytokines during the wound healing process.     

Diabetes impairs adipose tissue–derived stem cell function and efficiency in promoting wound healing

Adipose tissue–derived stem cells (ASCs) are gaining increasing consideration in tissue repair therapeutic application. Recent evidence indicates that ASCs enhance skin repair in animal models of impaired wound healing. To assess the therapeutic activity of autologous vs. allogeneic ASCs in the treatment of diabetic ulcers, we functionally characterized diabetic ASCs and investigated their potential to promote wound healing with respect to nondiabetic ones. Adipose tissue–derived cells from streptozotocin‐induced type 1 diabetic mice were analyzed either freshly isolated as stromal vascular fraction (SVF), or following a single passage of culture (ASCs). Diabetic ASCs showed decreased proliferative potential and migration. Expression of surface markers was altered in diabetic SVF and cultured ASCs, with a reduction in stem cell marker‐positive cells. ASCs from diabetic mice released lower amounts of hepatocyte growth factor, vascular endothelial growth factor (VEGF)‐A, and insulin‐like growth factor‐1, growth factors playing important roles in skin repair. Accordingly, the supernatant of diabetic ASCs manifested reduced capability to promote keratinocyte and fibroblast proliferation and migration. Therapeutic potential of diabetic SVF administered to wounds of diabetic mice was blunted as compared with cells isolated from nondiabetic mice. Our data indicate that diabetes alters ASC intrinsic properties and impairs their function, thus affecting therapeutic potential in the autologous treatment for diabetic ulcers.     

Extracellular matrix/stromal vascular fraction gel conditioned medium accelerates wound healing in a murine model

Conditioned medium (CM) is a new treatment modality in regenerative medicine and has shown a successful outcome in wound healing. We recently introduced extracellular matrix/stromal vascular fraction gel (ECM/SVF‐gel), an adipose‐derived stem cell and adipose native extracellular matrix‐enriched product for cytotherapy. This study aimed to evaluate the effect of CM from ECM/SVF‐gel (Gel‐CM) on wound healing compared with the conventional CM from adipose tissue (Adi‐CM) and stem cell (SVF‐CM). In vitro wound healing effect of three CMs on keratinocytes and fibroblasts was evaluated in terms of proliferation property, migratory property, and extracellular matrix production. In vivo, two full‐thickness wounds were created on the back of each mice. The wounds were randomly divided to receive Gel‐CM, Adi‐CM, SVF‐CM, and PBS injection. Histologic observations and collagen content of wound skin were made. Growth factors concentration in three CMs was further quantified. In vitro, Gel‐CM promoted the proliferation and migration of keratinocytes and fibroblasts and enhanced collagen I synthesis in fibroblasts compared to Adi‐CM and SVF‐CM. In vivo, wound closure was faster, and dermal and epidermal regeneration was improved in the Gel‐CM‐treated mice compared to that in Adi‐CM and SVF‐CM‐treated mice. Moreover, The growth factors concentration (i.e., vascular endothelial growth factor, basic fibroblast growth factor, hepatocyte growth factor, and transforming growth factor‐β) in Gel‐CM were significantly higher than those in Adi‐CM and SVF‐CM. Gel‐CM generated under serum free conditions significantly enhanced wound healing effect compared to Adi‐CM and SVF‐CM by accelerating cell proliferation, migration, and production of ECM. This improved trophic effect may be attributed to the higher growth factors concentration in Gel‐CM. Gel‐CM shows potential as a novel and promising alternative to skin wound healing treatment. But limitations include the safety and immunogenicity studies of Gel‐CM still remain to be clearly clarified and more data on mechanism study are needed.     

Overexpression and regulation of expression of scatter factor/hepatocyte growth factor in prostatic carcinoma

Objectives. Scatter factor (hepatocyte growth factor) (SF/HGF) is a multifunctional polypeptide growth factor that has been implicated in tumor proliferation, angiogenesis, invasiveness, and metastasis. Little is known of the expression of SF/HGF in human prostatic carcinoma. The aims of this investigation were to quantitate the level of SF/HGF expression in benign versus malignant human prostatic tissues and to assess regulation of SF/HGF expression by human prostatic stromal myofibroblasts.Methods. We determined the level of SF/HGF expression in 10 human prostatic tissue samples (5 benign, 5 carcinoma) by Western blot analysis. Five purified growth factors—basic fibroblast growth factor (bFGF), interleukin-1beta (IL-1β), platelet-derived growth factor (PDGF), vascular endothelial growth factor (VEGF), and endothelial growth factor (EGF)—were tested for their capacity to induce SF/HGF expression by a human prostatic stromal myofibroblastic cell line, as assessed by enzyme-linked immunosorbent assay. Supernatant from the normal PrEC prostatic epithelial cell line and the DU 145 carcinoma cell line were assayed for SF/HGF-inducing activity.Results. SF/HGF exhibited a mean fourfold overexpression in carcinoma tissues compared with benign prostatic tissue. Significant stimulation of SF/HGF expression by prostatic stromal myofibroblasts was detected for IL-1β (8.1-fold), PDGF (6.2-fold), bFGF (4.0-fold), VEGF (3.7-fold), and EGF (2.9-fold). DU 145-conditioned media, but not the PrEC-conditioned media, contained SF/HGF-inducing activity, which was determined to include IL-1β, bFGF, and PDGF by antibody-blocking experiments.Conclusions. SF/HGF is overexpressed in human prostatic carcinoma tissues. Prostatic carcinoma cell stimulation of SF/HGF expression by adjacent benign myofibroblastic cells as a type of epithelial–stromal paracrine interaction could potentially influence prostatic carcinoma cell behaviors.     

Revascularization of transplanted pancreatic islets following culture with stimulators of angiogenesis

BACKGROUND: Insufficient revascularization of transplanted islets may result in chronic hypoxia and loss of islet function. This study investigated whether simple culture of islets with angiogenic substances before transplantation could improve graft revascularization. METHODS: Mouse islets were cultured with vascular endothelial growth factor (VEGF; 20 ng/ml), fibroblast growth factor 2 (FGF-2; 20 ng/ml) or matrix metalloproteinase 9 (MMP-9; 1 mug/ml). Thereafter, 250 islets were implanted beneath the renal capsule of syngeneic C57Bl/6 mice. One month posttransplantation, blood flow (laser-Doppler flowmetry), oxygen tension (Clark microelectrodes), and vascular density were measured and correlated to graft function. RESULTS: Treatment of islets with VEGF during culture caused islet blood vessels to dilate, whereas FGF-2 treatment induced endothelial cell proliferation. However, the number of capillaries in both cases decreased during culture. When investigated one month posttransplantation, both VEGF and FGF-2 pretreated islets had similar or worse vascular engraftment when compared to transplanted control islets. MMP-9 pretreatment of islets increased vascular density, blood flow and oxygen tension within the grafts. Animals receiving MMP-9 pretreated islets returned, however, more slowly to normoglycemia than control animals, and performed worse than controls in a glucose tolerance test one month posttransplantation. CONCLUSIONS: Treatment of islets during culture with VEGF or FGF-2 changed the islet vascular phenotype, but capillaries were still lost. Notably, the number of capillaries in the grafted islets one month posttransplantation was in all cases strikingly similar to that observed prior to transplantation. MMP-9 pretreatment of islets elicited an angiogenic response, which improved revascularization of the transplanted islets.     

Angiogenesis and proliferation of endothelial cells in hypertrophic and nodular port-wine stain

BackgroundPort-wine stain (PWS) has been classified not as the hyperplasia of cells, but rather, as an expansion of malformed vessels. However, previous studies have reported upregulated expression of proangiogenic factors in PWS. Several studies have indicated that the pathology exhibits proliferation of numerous endothelial cells in hypertrophic/nodular PWS. This study aimed to determine the expression of vascular epithelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9), angiopoietin-2 (ANG-2), and basic fibroblast growth factor (bFGF) in hypertrophic PWS.MethodsImmunohistochemistry was used to analyze skin samples from 33 patients with hypertrophic PWS. Expression levels of VEGF, MMP-9, ANG-2, and bFGF in hypertrophic PWS were determined by multiplying the intensity by the percentage of immunoreactive cells. Immunoreactivity scores were classified as follows: negative (0), low (1), moderate (2, 3, and 4), or high (6).ResultsBased on pathological characteristics, hypertrophic PWS was divided into vascular malformation and pyogenic granuloma (PG) types. VEGF, MMP-9, ANG-2, and bFGF were significantly activated in the blood vessels of PG-type PWS samples compared with their counterparts in blood vessels of vascular malformation-type PWS samples and controls. PG-type hypertrophic PWS, which exhibited proliferation of endothelial cells, showed the strongest activation.ConclusionThe exuberant proliferation of endothelial cells in PG-type hypertrophic PWS may be associated with the regulation of proangiogenic factors during development. These proangiogenic factors that function in the angiogenesis and proliferation of endothelial cells may play an important role in the pathogenesis and progression of PWS. Furthermore, these factors may be dynamic and behave differently in various types of hypertrophic PWS.     

Stromal cell-derived factor-1 and vascular endothelial growth factor as biomarkers for lymph node metastasis and poor cancer-specific survival in prostate cancer patients after radical prostatectomy

ObjectivesThis study aims to analyze the clinicopathologic significance of stromal cell-derived factor-1 (SDF-1), vascular endothelial growth factor (VEGF), and matrix metalloproteinase-9 (MMP-9) expression in human prostate cancer (CaP), and their involvement in the prognosis of CaP.Materials and methodsThe expression of SDF-1, VEGF, and MMP-9 were measured using immunohistochemistry in 148 CaP patients who underwent radical prostatectomy for clinically localized disease and in 10 samples of benign prostatic hyperplasia (BPH).ResultsIn the CaP group, VEGF and MMP-9 were more strongly expressed in the tumor cells compared with the BPH group. High intensity SDF-1, VEGF, and MMP-9 stains in tumor areas strongly correlated with lymph node metastasis, pathologic stage, and differentiation. Univariate and multivariate analysis showed that SDF-1, VEGF, and lymph node metastasis were independent prognostic factors for prostate cancer-specific survival. High levels of MMP-9, pathologic stage, and differentiation were associated with prostate cancer-specific survival in univariate analysis but the risk estimate was not significant in multivariate analysis.ConclusionsHigh expression levels of SDF-1, VEGF, and MMP-9 are more correlated with lymph node metastatic prostate carcinoma compared with non-lymph-node metastatic cancer. High expression levels of SDF-1 and VEGF strongly predict the biochemical progression in CaP patients after radical prostatectomy.     

A review of the effects of insulin-like growth factor and platelet derived growth factor on in vivo cartilage healing and repair

Growth factors may enhance current cartilage repair techniques via multiple mechanisms including recruitment of chondrogenic cells (chemotaxis), stimulation of chondrogenic cell proliferation (mitogenesis) and enhancement of cartilage matrix synthesis. Two growth factors that have been studied in cartilage repair are insulin-like growth factor (IGF) and platelet derived growth factor (PDGF). IGF plays a key role in cartilage homeostasis, balancing proteoglycan synthesis and breakdown. Incorporating IGF into a fibrin clot placed in an equine cartilage defect improved the quality and quantity of repair tissue and reduced synovial inflammation. PDGF is a potent mitogenic and chemotactic factor for all cells of mesenchymal origin, including chondrocytes and mesenchymal stem cells. Resting zone chondrocytes cultured with PDGF demonstrated increased cell proliferation and proteoglycan production, while maturation of these cells along the endochondral pathway was inhibited. Pretreating chondrocytes with PDGF promotes heterotopic cartilage formation in the absence of any mechanical stimulus. PDGF has also been shown to be a potent stimulator of meniscal cell proliferation and migration. These studies and others suggest a potential role for these potent biological regulators of chondrocytes in cartilage repair. More work needs to be performed to define their appropriate dosing and the optimum delivery method. Combining tissue growth factors with a biological matrix can provide a physical scaffold for cell adhesion and growth as well as a means to control the release of these potent molecules. This could result in biological devices that enhance the predictability and quality of current cartilage repair techniques.     

Temporal and quantitative profiles of growth factors and metalloproteinases in acute wound fluid after mastectomy

Seventy-three samples of acute wound fluid were collected from 47 patients during the first 3 postoperative days (POD) following mastectomy for cancer ( n =47 on POD-1, n =19 on POD-2, and n =7 POD-3). Samples were analyzed by enzyme-linked immunosorbent assay for growth factor levels (epidermal [EGF], platelet-derived [PDGF], basic fibroblast [bFGF], transforming growth factor-β1 [TGF-β1], vascular endothelial [VEGF]), interleukin-6 (IL-6), matrix metalloproteinases (MMPs-2, -3, -9), and the tissue inhibitor of metalloproteinase 1 (TIMP-1). The levels of EGF, bFGF, PDGF, and interleukin-6 peaked on POD-1, with a significant decrease by POD-3, while total and active MMP-2, MMP-3, and tissue inhibitor of metalloproteinase 1 showed a progressive and significant increase from days 1 to 3. The wounds that later developed an infection (11%) were found to have a significantly lower PDGF and EGF on day 1 (PDGF, median 169 pg/mL [range, 86–2,595]) than the noninfected wounds (2,098 [17–66,506] p <0.05, Mann–Whitney U -test). Sixty-two percent patients developed a seroma and the levels of bFGF were significantly less in these patients (441 pg/mL [45–4,108]) than in those patients where there was no seroma (807 [245–3,133] p <0.05). The levels of certain growth factors in acute wound fluid may be important markers for wound outcomes.     

VEGF在胃癌中的表达及其侵袭机制的研究

目的：探讨血管内皮生长因子（VEGF）在胃癌组织中的表达及其对基质金属蛋白酶-9（MMP-9）的表达的影响在胃癌侵袭机制中的意义。方法：采用免疫组织化学法、MTT法、实时定量PCR及Westernblot,观察胃癌组织及癌旁组织中VEGF的表达、VEGF对胃癌AGS细胞增殖和AGS细胞中MMP-9mRNA及蛋白表达的影响。结果：VEGF在胃癌中高表达;经VEGF刺激后,AGS细胞增殖明显,MMP-9mRNA及蛋白表达亦明显增加,具有统计学意义（P〈0.05）。结论：VEGF通过上调MMP-9的表达促进胃癌的侵袭转移,VEGF和MMP-9可作为了解胃癌生物学行为和判断预后的指标。     

Angiogenesis in renal cell carcinoma: Evaluation of microvessel density, vascular endothelial growth factor and matrix metalloproteinases

BACKGROUND: Angiogenesis, the growth of new blood vessels, has a critical role in tumor growth and metastasis. The purpose of this study was to investigate the involvement of angiogenesis and angiogenic factors in the pathogenesis of renal cell carcinoma (RCC). METHODS: Formalin-fixed and paraffin-embedded tissue blocks from 70 patients with RCC were studied. The situations of tumor angiogenesis were evaluated by assessing microvessel density (MVD) through CD31 immunostaining. The expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2 (MMP-2) and metalloproteinase-9 (MMP-9) was detected immunohistochemically. RESULTS: The value of MVD ranged from 12.0 to 93.0 with a median of 39.91 in RCC. Of the 70 RCCs, the expression of VEGF was detected in 52 (74.3%), MMP-2 in 29 (41.4%) and MMP-9 in 19 (27.1%) cases. Statistical analysis revealed significant associations of the tumor stage with MVD, and the expression of VEGF and MMP-2 in RCC. Additionally, MVD was closely related to the expression of VEGF but was not related to the expression of MMP-2 and MMP-9 in RCC. CONCLUSION: The degree of angiogenesis may be closely related to the tumor progression of RCC. The expression of VEGF may be responsible for angiogenesis in RCC, and both VEGF and MMP-2 expression may function as tumor associated angiogenic factors in RCC.     

Expression of growth factors in canine flexor tendon after laceration in vivo

Growth factors, transforming growth factor beta (TGF-beta), epidermal growth factor (EGF), platelet-derived growth factor (PDGF), insulin-like growth factor (IGF), basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF), are critical components of the cutaneous wound healing process. Little is known, however, about the expression of these growth factors in normal flexor tendon healing. In this study, we wished to examine which of these growth factors are present at 10 days following tendon injury in a canine flexor tendon repair model. Using immunohistochemical analysis, we found positive staining for all growth factors in both timing groups. TGF-beta was detected around the repair site and proximal to it. PDGF-AA, PDGF-BB and VEGF appeared in the whole tendon section following repair. EGF, IGF and bFGF were not seen in tenocytes but were present in inflammatory cells surrounding the repair site. These findings provide evidence that TGF-beta, EGF, PDGF-AA, PDGF-BB, IGF, bFGF and VEGF are all expressed at 10 days after tendon injury but by different cell types and in different locations. The time course of growth factor expression is an important element in wound healing, and a better understanding of where and when such factors are expressed may help in the development of methods to manipulate this expression, accelerate healing, and reduce adhesions.     

MMP-9、Bcl-2、VEGF在肾细胞癌中的表达及意义

目的通过检测MMP-9、Bcl-2及血管内皮生长因子(VEGF)在肾细胞癌中的表达,探讨它们在肾细胞癌的发生、发展和转移中的作用及其相互之间的关系。方法用免疫组织化学方法检测68例肾细胞癌石蜡标本中MMP-9、Bcl-2和VEGF的蛋白表达情况,并进行统计学分析。结果在正常肾组织和肾细胞癌中MMP-9、Bcl-2和VEGF的表达有显著性差异(P0.05)。MMP-9、Bcl-2的阳性表达与肾细胞癌病理分级、临床分期之间无显著性差异(P0.05)。VEGF阳性表达率随病理分级、临床分期的升高而升高。VEGF在病理分级Ⅰ与Ⅱ和Ⅰ与Ⅲ之间的表达有显著性差异(P0.05),在临床分期中,早期与晚期有显著性差异(P0.05)。MMP-9和VEGF表达率在淋巴结转移阳性组显著高于淋巴结阴性组。结论 MMP-9、Bcl-2和VEGF在肾细胞癌的形成过程中可能起作用。MMP-9很可能与肾细胞癌的侵袭和转移密切相关,VEGF可作为判断肾细胞癌淋巴结转移和临床预后的生物学指标。