Tissue Growth Factor Research Articles

Reduction of infarct size in the rat heart by LPS preconditioning is associated with expression of angiogenic growth factors and increased capillary density.

Inflammation induces the expression of angiogenic growth factors in tissues, which leads to microvascular growth. Bacterial lipopolysaccharide (LPS) provokes a transient inflammatory response in the heart and induces delayed cardiac resistance to post-ischemic contractile dysfunction. In this study, we examined: 1) the effects of LPS on myocardial expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF), 2) whether an increase in the density of myocardial microvessels follows the expression of angiogenic growth factors, and 3) the effect of LPS on myocardial resistance to infarction and its relationship with microvascular growth. Rats were treated with LPS (from Salmonella typhimurium, 0.5 mg/kg i.p.). The expression of bFGF and VEGF in the myocardium was examined at 6 and 12 h after LPS treatment by immunofluorescent staining. Myocardial capillary and arteriole densities were determined 3 days after LPS treatment by morphometry, using immunofluorescent staining of von Willebrand factor (a marker protein of endothelial cells) and alpha-smooth muscle actin (a marker protein of smooth muscle cells). To examine cardiac resistance to infarction, hearts were subjected to 40 min of regional ischemia and 2 h of reperfusion by reversible occlusion of left coronary artery at 3 days after LPS treatment. LPS induced cardiac bFGF and VEGF at 6 and 12 h after treatment. The expression of these growth factors was followed by an increase in myocardial capillary density (2032 +/- 78/mm2 vs. 1617 +/- 47/mm2 in saline control, P < 0.05), but not arteriole density, at 3 days. Meanwhile, infarct size was significantly reduced by LPS preconditioning (infarct/left ventricle 12.3 +/- 1.04% vs. 21.7 +/- 1.65% in saline control, 43% reduction, P < 0.05). These results suggest that LPS preconditioning induces cardiac bFGF and VEGF, and an increase in myocardial capillary density. This increased myocardial capillary density is associated with a reduced infarct size after in vivo regional ischemia-reperfusion.

Expression of platelet-derived endothelial cell growth factor in prostatic adenocarcinoma.

Angiogenesis is thought to play critical roles in local tumor growth and eventual metastasis. No studies have examined the expression of platelet-derived endothelial cell growth factor (PD-ECGF) in prostatic tissues. Prostatic tissues were obtained from 36 prostatic adenocarcinoma patients. We assessed the expression of PD-ECGF using ELISA and immunohistochemistry. The mean level of PD-ECGF in prostatic adenocarcinomas was higher than that in neighboring normal prostatic tissues in ELISA. Immunohistochemistry showed that the expressions of PD-ECGF, which were associated with increase of microvessel count, were found in the endothelial cells, macrophages, lymphocytes, or fibroblasts. These results suggest that PD-ECGF is involved in the development of prostatic adenocarcinoma.

Comparison between 'in vivo' and 'in vitro' methods for evaluating tumor angiogenesis using cervical carcinoma as a model.

The role of angiogenesis in tumorigenesis is widely accepted. Therefore, it is mandatory to develop a clinically useful method for assessing tumor angiogenesis. This study was designed to compare the 'in vivo' and 'in vitro' methods for assessing angiogenesis and to evaluate their clinical application using cervical carcinoma as a model. Ninety women with stages IB-IIA cervical carcinoma exhibiting visible cervical tumors by transvaginal ultrasound were enrolled in this study. All patients underwent radical abdominal hysterectomy and pelvic lymph node dissection. Vascularity index (VI) was assessed by power Doppler ultrasound and a quantitative image processing system. The microvessel density (MVD) of the excised tumors was immunohistochemically assessed. Both the enzyme immunoassay and immunohistochemistry methods were performed for assessing the protein levels of vascular endothelial growth factor (VEGF) in tumor tissues. Significantly higher VI, MVD and cytosol VEGF concentrations were detected in tumors with deep stromal invasion (>or=1/2 thickness) (11.43 +/- 7.25 vs. 5.87 +/- 6.81, P < 0.001; 53.0 vs. 37.0, P = 0.006, 550.0 vs. 86.0 pg/mg, P < 0.001), lymphatic invasion (12.21 +/- 7.89 vs. 6.86 +/- 6.29, P < 0.001; 53.0 vs. 40.0, P = 0.038; 930.0 vs. 110.0 pg/mg, P = 0.002), and pelvic lymph node metastasis (17.15 +/- 8.58 vs. 7.83 +/- 6.41, P < 0.001; 54.0 vs. 39.0, P = 0.02; 964.0 vs. 131.0 pg/mg, P = 0.002). VEGF-rich tumors detected by immunohistochemistry also revealed higher VI (12.26 +/- 7.96 vs. 8.05 +/- 7.62, P = 0.012), MVD (53.0 vs. 37.5, P = 0.01) and cytosol VEGF levels (745.0 vs. 98.0 pg/mg, P = 0.002). The relationships between VI values, MVD values and cytosol VEGF concentrations were linear (VI vs. MVD, r = 0.38, P < 0.001; VI vs. VEGF, r = 0.78, P < 0.001; MVD vs. VEGF, r = 0.29, P = 0.006). As revealed by the receiver operating characteristic (ROC) curve analysis, VI is better than MVD and VEGF in predicting lymph node metastasis. In conclusion, there is histological, molecular and clinical evidence supporting VI as a useful 'in vivo' indicator of tumor angiogenesis, particularly for predicting lymph node metastases in cervical carcinomas.

Detection of receptor transcripts for androgen, epidermal growth factor and basic fibroblast growth factor in human prostate postmortem.

RNA isolated from frozen human postmortem prostate tissue was evaluated for its utility in molecular biological studies based on RNA analysis. Our results on slot-blot analysis show the presence of receptor transcripts for androgen, epidermal growth factor and basic fibroblast growth factor in postmortem prostate tissue obtained 20-120 hrs after death. However, the RNA in these samples was found to be degraded as revealed by the absence of ribosomal bands on gel electrophoresis. AR mRNA was found to be present in one of the five samples when analysed by northern blotting.

Endocrine effects of IGF-I on normal and transformed breast epithelial cells: potential relevance to strategies for breast cancer treatment and prevention.

Insulin-like growth factors (IGFs) are mitogenic and anti-apoptotic peptides that influence the proliferative behavior of many cell types, including normal and transformed breast epithelial cells. IGF-I has properties of both a tissue growth factor and a systemic hormone: there is evidence that IGF bioactivity in tissues is influenced not only by local factors such as tissue expression of IGFs, IGF binding proteins (IGFBPs), and IGFBP proteases, but also by factors that regulate whole-body IGF physiology and circulating IGF-I levels. Experimental evidence that interventions that reduce circulating IGF-I levels reduce proliferation of breast neoplasms has raised interest in the possibility of developing novel endocrine therapies that target the growth hormone/IGF-I axis. Furthermore, influences of the growth hormone/IGF-I axis on normal breast epithelial cells may underlie recent epidemiological observations that suggest that premenopausal women with high circulating IGF-I level are at increased risk for breast cancer. These studies suggest that the growth hormone/IGF-I axis deserves investigation as a possible target for novel breast cancer prevention strategies.

Triiodothyronine (T3), insulin and characteristics of 5'-monodeiodinase (5'-MD) in mare's milk from parturition to 21 days post-partum.

It is generally accepted that hormones and tissue growth factors are supplied from mother to neonate via mammary secretion. Among the protein hormones, insulin and prolactin are considered as the most important milk components for neonates. The significance of the thyroid hormones, namely triiodothyronine (T3) generated locally by 5'-monodeiodinase (5'-MD) in the mammary tissues, for the mammary gland itself and for suckling neonates is still under consideration. In the present study the activity of the 5'-MD and the concentrations of T3 and insulin in mare's colostrum and milk during the first 21 days of lactation were measured. Post partum, T3 increased to its highest concentration around day 4 (1.14+/-0.08 nmol/L), then progressively decreased until day 7, reaching a relatively stable concentration of 0.71+/-0.06 nmol/L (overall mean for days 7-21). The colostral insulin concentration, highest on the day of parturition (401.0 +/-24.9 microU/mL), decreased to a nadir value (25.0+/-3.4 microU/mL) on day 5, after which it tended to increase. The mare's milk showed the presence of PTU-sensitive (type I) and PTU-insensitive (type II) 5'-monodeiodinases (5'-MD). Contrary to the classical type II 5'-MD, the mare's milk isoenzyme was inhibited non-competitively by aurothioglucose. A significant relationship (r=0.962, P < 0.01 ) between T3 concentration and 5'-MD activity, from the I st to the 6th lactational day was found, which may indicate a dependence of T3 concentration on the milk 5'-MD activity. The presence of 5'-MD of type II suggests that intra-mammary T3 generation may play a paracrine role supporting lactogenesis. Estimating that 1.8 microg of colostral T3 (0.456 microg/L) is consumed daily by a suckling foal, the T3 hormone action within the intestinal tract cannot be ruled out. This is the first paper to provide evidence of T3 and insulin concentrations, and of T4-5'-monodeiodinases activity in colostrum and milk of the mare.

Expression and response to hypoxia of vascular endothelial growth factor (VEGF) in rat and rabbit tissues.

VEGF is a potent and specific endothelial cell mitogen and an important regulator and inducer of angiogenesis. Recent finding of capillary budding in hypoxic rat brain suggested that hypoxia might initiate angiogenesis in brain. As a key factor of angiogenesis VEGF is thought to be potent in the basement membrane destruction and leakage. It can enhance microvascular permeability with a potency some 50,000 times that of histamine,11 which is likely to elicit hypoxic cerebral edema. The pathologic findings of cerebral thrombosis and petechial hemorrhages12 in high altitude cerebral edema are also consistent with VEGF physiological effects such as induction of thromboplastin activity5 and stimulation of von Willebrand factor release from endothelial cells.2 We surmise that VEGF may contribute to hihgh altitude cerebral edema (HACE). Here we report the expression and responce to hypoxia of VEGF mRNA, VEGF protein and its receptor (flt-1) in hypoxic tissues

629 Prognostic value of basic fibroblast growth factor and vascular endothelial growth factor in non-small cell lung cancer tissue

629 Prognostic value of basic fibroblast growth factor and vascular endothelial growth factor in non-small cell lung cancer tissue

Overview of therapeutic drug monitoring and biotechnologic drugs.

Therapeutic drug monitoring (TDM) is the science that combines measurement of serum drug concentrations with clinical pharmacokinetics. Biotechnological drugs may be obtained by recombinant DNA technology, monoclonal antibody technology, polymerase chain reaction, gene therapy, nucleotide blockade, peptide technology, and carbohydrate technology. Examples of biotechnological drugs include antisense drugs, clotting factors, hematopoietic factors, hormones, interferons, interleukins, monoclonal antibodies, tissue growth factors, and vaccines. For drugs that are physiological peptides used for substitution therapy, TDM is not indicated. For other biotechnological drugs, the criteria developed for monitoring of "classical" therapeutic agents should be used on an individual basis to determine whether there is a role for TDM.

Alterations in the level of phosphotyrosine signal transduction constituents in human parotid tumors.

Human parotid tumors were evaluated for the activation of the phosphotyrosine signaling pathway by Western blot, enzyme activity assay, and reverse transcriptase-polymerase chain reaction. Warthin's tumor and mucoepidermoid carcinomas had the greatest level of tyrosine phosphorylated proteins identified in plasma membrane fractions. These tumors, along with pleomorphic adenocarcinoma, showed high levels of membrane expression of the tyrosine kinase receptor, c-erbB-2, and phosphatidylinositol-3-kinase. Expression of the epidermal growth factor receptor was confined to normal tissue. The level of mRNA for c-erb was elevated only in mucoepidermoid carcinomas. Messenger RNA levels for ras were unchanged from control levels in all tumors, while the level of src mRNA was higher in the tumor samples than the normal parotid tissue. The activities of several signal transduction kinases, including protein kinase A and C were elevated in tumor tissue (7.7- to 18.9- and 0.4- to 3.7-fold higher, respectively), relative to surrounding normal tissue. While the level of glandular amylase was reduced (22%-0% of normal levels) in the tumor tissue, epidermal growth factor (EGF) and transforming growth factor-alpha (TGFalpha) content was dramatically higher in the neoplastic tissue (10- to 170-fold and 4.6- to 6.0-fold, respectively). These results suggest that with the presence of elevated levels of EGF, TGFalpha, and the oncoprotein receptor c-erbB-2 in the membrane of parotid tumors, cell proliferation and activation of the phosphotyrosine signal transduction pathway may involve autocrine stimulation through the expression of high levels of growth factor and receptor in the same tissue.

Transforming growth factor in lacrimal gland tissue

After the demonstration of the epidermal growth factor (EGF) in lacrimal gland tissue the author investigated lacrimal gland tissue for TGF-alpha. This growth factor has structural similarities to EGF, binds to the same receptor and has also wound healing promoting effects. Stained with specific antibodies 30 specimens of bovine lacrimal glands were investigated immunohistochemically for the presence of TGF-alpha. In all sections TGF-alpha was detected in the acini. Here it was located in the lacrimocytes in a pattern that resembles the localization of the secretory granules. This gives strong evidence that also TGF-alpha is, like suggested for EGF, produced and secreted by the lacrimal gland. This implies the possibility that also TGF-a is present in tear fluid, an initial result that is strongly supported by recent studies. It is concluded that the current models on the effect of EGF on the ocular surface should also consider the simultaneous presence of TGF-a. The possibility that both growth factors a...

Human pituitary adenomas express endogenous inhibin subunit and follistatin messenger ribonucleic acids.

Specific factors involved in the pathogenesis of tumors that stimulate clonal human pituitary adenoma cell proliferation remain unknown. An important question regarding the pathogenesis of human pituitary tumors is whether they synthesize autocrine regulatory factors that regulate both hormone biosynthesis and neoplastic growth. Activin and inhibin are both comprised of inhibin subunits and have diverse regulatory roles as growth and differentiation factors in normal and neoplastic tissue. Activin stimulates FSH beta messenger ribonucleic acid (mRNA) biosynthesis and FSH secretion, and these effects are down-regulated in normal gonadotrophs by the endogenous glycoprotein follistatin. In addition to its effects on gonadotrophs, activin modulates hormone secretion by somatotroph and corticotroph cell lines. It is not known whether human neoplastic pituitary tissue synthesizes inhibin subunits or follistatin or whether their expression is cell type specific. We investigated whether alpha-, beta A-, and beta B-inhibin subunit and follistatin mRNAs could be detected in 27 human pituitary adenomas [clinically nonfunctioning (n = 11), somatotroph (n = 5), corticotroph (n = 5), and lactotroph (n = 6)] using reverse transcriptase-polymerase chain reaction techniques. Twenty-six of the tumors contained mRNAs encoding one or more inhibin subunits. beta B-Inhibin mRNA was the most prevalent (81% of tumors), followed by beta A-inhibin (59% of tumors) and alpha-inhibin (52% of tumors). Endogenous alpha-, beta A-, and beta B-inhibin subunit mRNA synthesis was also examined in normal human pituitary and testicular complementary DNA libraries, and all subunit mRNAs were detected. In contrast to the widespread expression of inhibin subunits in pituitary tumors, follistatin mRNA was detected in a subset of nonfunctioning tumors (54%) as well as in control normal human pituitary and testicular complementary DNA libraries. Tumor-specific follistatin biosynthesis was not observed in other pituitary tumor subtypes. These data are the first to demonstrate that 1) endogenous inhibin subunits are synthesized in human pituitary adenomas of all known secretory phenotypes as well as normal pituitary tissue; and 2) follistatin gene expression in pituitary adenomas is specific to clinically nonfunctioning or gonadotropin subunit-producing tumors. The characterization of inhibin subunit and follistatin biosynthesis by human pituitary tumors will be important in investigating their potential roles in regulating both tumor phenotype and cell proliferation.

Localization of hepatocyte growth factor (HGF) in human placental tissues

Localization of hepatocyte growth factor (HGF) in human placental tissues

Transcriptional regulation of basic fibroblast growth factor gene by p53 in human glioblastoma and hepatocellular carcinoma cells.

Mutations of the p53 gene are found in various human cancers. The frequency of its mutation is reported to increase during tumor progression in most tumors. In human gliomas, mutations of the p53 gene are found in about one-third of the malignant forms and in few of the benign ones, indicating their possible involvement in tumor progression. On the other hand, we have recently shown that basic fibroblast growth factor (basic FGF) plays a crucial role in tumor progression as an autocrine growth factor in tissues of human gliomas. Therefore, we hypothesized that p53 might regulate the promoter activity of the basic FGF gene, which has several GC boxes and no typical TATA box. In this study, cotransfection assays using human glioblastoma and hepatocellular carcinoma cells and establishment of stable cell lines expressing mutant-type p53 were performed. The basic FGF gene promoter was demonstrated to be regulated by p53 at the transcriptional level and its basal core promoter was found to be responsive to p53. Expression of endogenous basic FGF was also demonstrated to be activated by mutant type p53. Wild-type p53 repressed gene expression of the basic FGF and its mutant activated it in vitro, implying one of the possible pathways in tumor progression.

Regulation by Androgen of Levels of the β Subunit of Nerve Growth Factor and Its mRNA in Selected Regions of the Mouse Brain

Our previous studies showed that the concentration of the beta subunit of nerve growth factor (beta-NGF) in nervous tissues is higher in male than in female mice. To identify the brain regions that are affected by androgens, the amounts of beta-NGF protein and its mRNAs were measured in male, female, and castrated male CD-1 mice and testicular feminization mice at 3-4 months of age. Among tissues examined, the hypophysis of males contained the highest average concentration of beta-NGF protein. In most regions of the brain, individual levels were more variable in males than in females. However, after the castration, such variations in beta-NGF levels disappeared. Average levels of beta-NGF protein in males were higher in the cerebellum (eightfold higher), olfactory bulb (12-fold higher), hypothalamus (sixfold higher), and hypophysis (72-fold higher) than those in corresponding regions of females. No significant differences were observed in levels of beta-NGF protein in the hippocampus, cerebral cortex, striatum, septum, and brainstem. The castration of male mice caused a reduction in levels of beta-NGF protein in the hypothalamus and hypophysis, but not in the cerebellum and olfactory bulb, to the female levels. The concentrations of beta-NGF protein in testicular feminization mice were similar to those in female CD-1 mice in all regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Distribution of epidermal growth factor in rat ocular and periocular tissues

Using a sensitive radioimmunoassay (RIA) specific for rat epidermal growth factor (rEGF), we investigated the presence of rEGF in a variety of rat ocular and periocular tissues. Immunoreactive rEGF (IR-rEGF) was present in tear fluids (25.5 +/- 5.8 ng/ml), exorbital lacrimal gland (6.73 ng/g wet weight), intraorbital lacrimal gland (2.80 ng/g wet weight), Harderian gland (1.90 ng/g wet weight), and conjunctiva (0.16 ng/g wet weight). EGF was not detectable in aqueous humor, cornea, iris and ciliary body, lens, or the posterior part of the globe (retina, choroid, and vitreous body). Gel exclusion chromatography and reverse-phase high-performance liquid chromatography revealed that IR-rEGF in the above ocular fluids and tissues was indistinguishable from standard rEGF. Using enzyme-linked immunohistochemistry, rEGF was demonstrated to be localized in the duct epithelial cells of lacrimal glands. These findings reveal that EGF is preferentially localized in the ocular surface and lacrimal apparatus.

The Effects of ACE Inhibition on Progression of Atherosclerosis

Angiotensin-converting enzyme inhibitors have been extensively studied and established in the treatment of hypertension, heart failure, and ventricular dysfunction. They have various cardiac and vascular protective effects, but the relevant mechanisms of action in these areas remain to be fully understood. Possible effects of converting-enzyme inhibition related to maintenance of normal endothelial function and inhibition of atherosclerosis should be distinguished from effects on myointimal proliferation related to vascular injury and regression of vascular hypertrophy from blood pressure reduction. Experimental animal studies have showed benefit from converting-enzyme inhibition in preventing myointimal proliferation after vascular injury in some species, but no such effect has been shown in clinical studies of restenosis following coronary angioplasty. Laboratory studies have demonstrated a protective effect of converting-enzyme inhibition on endothelial vasomotor function. Further studies have demonstrated prevention of atherosclerosis in hyperlipidemic rabbits and cholesterol-fed cynomolgus monkeys. Possible mechanisms of action apart from blood pressure lowering include inhibition of angiotensin II and other tissue growth factors and accumulation of kinins. These data, among others, provide sufficient rationale for clinical studies to determine whether converting-enzyme inhibitors can reduce atherosclerotic disease and thus widen their application as cardiac and vascular protective agents.

Influence of malnutrition on humoral growth factors in plasma and liver tissue during liver regeneration

Influence of malnutrition on humoral growth factors in plasma and liver tissue during liver regeneration

Growth factors in ocular proliferative tissues

Growth factors in ocular proliferative tissues

Platelet-derived growth factor (PDGF), epidermal growth factor (EGF), and EGF and PDGF beta-receptors in human endometrial tissue: localization and in vitro action.

Human endometrial tissue and primary stromal cell culture contain immunoreactive epidermal growth factor (EGF), platelet-derived growth factor (PDGF)-AB as well as EGF and PDGF-beta receptors. The immunostaining for EGF, EGF receptor, and PDGF beta-receptor were associated with endometrial luminal and glandular epithelial and stromal cells, whereas only the stromal cells contain immunoreactive PDGF-AB. The immunostaining intensity of EGF, EGF receptor, and PDGF-AB was similar in both phases of the menstrual cycle, whereas, PDGF-beta receptor immunostaining was highest in proliferative phase and considerably reduced, particularly in luminal and glandular epithelial cells in the secretory phase. In addition primary stromal cell cultures express EGF, PDGF-AB, and contain EGF and PDGF-beta receptors, and very low levels of PDGF-alpha receptor. 3H-Thymidine incorporation indicate that after 48 h of incubation in serum-free medium approximately 75-80% of stromal cells are quiescent. Incubation of quiescent stromal cells with 10% fetal bovine serum stimulate 3H-thymidine incorporation in a time-dependent manner reaching maximal after 30-48 h, with a doubling time of 38.2 h. EGF (1.5-15 ng/ml) stimulates 3H-thymidine incorporation by quiescent stromal cells (P less than 0.001). This effect was significantly reduced at concentrations above 15 ng/ml (P less than 0.005). PDGF-AB (3-10 ng/ml) and PDGF-BB (0.5-10 ng/ml) also stimulate 3H-thymidine incorporation in quiescent stromal cells compared to controls (P less than 0.005). The action of EGF (15 ng/ml) and PDGF-AB (10 ng/ml) was time dependent, reaching maximal after 36 and 48 h of incubation (P less than 0.002). Addition of PDGF-AB (10 ng/ml) to EGF (15 ng/ml) significantly enhanced the action of EGF or PDGF-AB used individually (P less than 0.001). 17 beta-estradiol or progesterone at 1 microM did not stimulate 3H-thymidine incorporation, although they were stimulatory in combination (P less than 0.001), they did not alter the action of EGF or PDGF when added in combination. These observations provide further evidence that human endometrial tissue contains specific immunoreactive EGF receptors. It also demonstrates the presence of immunoreactive EGF, PDGF-AB, and PDGF-beta receptors in endometrial tissue as well as stromal cells in primary culture. Both EGF and PDGF are mitogenic for endometrial stromal cells, suggesting an autocrine/paracrine role in modulation of endometrial cell growth and differentiation.