Vascular endothelial growth factor (VEGF) is known to occur as at least six differentially spliced variants, giving rise to mature isoforms containing 121, 145, 165, 183, 189 and 206 amino acids. However, little is yet known concerning the in vivo activities of this differential splicing. Stably transfected MCF-7 breast carcinoma cells were constructed that secreted comparable amounts of the 121, 165 or 189 isoforms.
View Article and Find Full Text PDFA wide range of tumor response is seen amongst patients with the same stage of colorectal cancer, even with the use of uniform chemotherapy. The significant economic and personal impact of chemotherapy provides the impetus for the identification of markers of response for use in guiding patient treatment. However, practical constraints prevent evaluation of all putative markers in a definitive manner.
View Article and Find Full Text PDFOne of the current challenges in gene therapy is to construct a vector that will target specific tissues. Targeting expression to endothelium is of particular interest in the treatment of several pathologies. We have shown previously that defined regions of the E-selectin and KDR promoters confer endothelial cell specific expression following retroviral delivery.
View Article and Find Full Text PDFThe assessment of angiogenesis in breast cancer is of importance as a key indicator of survival and response to therapy. Circulating vascular endothelial growth factor (VEGF) measurements may provide a less subjective analysis than microvessel density (MVD) or immunohistochemical analysis of VEGF expression; however, most studies have used serum, which is now known to largely reflect platelet-derived VEGF concentrations. This study examined for the first time both plasma (VEGFp) and serum (VEGFs) VEGF concentrations in 201 blood samples from pre- and postmenopausal healthy controls and from patients with benign breast disease, localized breast cancer, breast cancer in remission, or metastatic breast cancer and related these to other clinicopathological markers.
View Article and Find Full Text PDFHeredity (Edinb)
February 2000
Apomixis, the asexual formation of seed, has been known in angiosperms for more than a century yet the genetic mechanisms that control this trait remain poorly understood. Most members of the genus Hieracium are apomicts, forming predominantly asexual seed. Some purely sexual forms, however, also exist.
View Article and Find Full Text PDFSteroids are commonly employed in current clinical practice. The benefits of steroids in hormone replacement therapy, contraception and prevention or treatment of breast cancer are limited by their side effects arising from disorders in endometrial function. These side effects are complex and enclose bleeding problems and endometrial proliferation during hormone replacement therapy and antioestrogen treatment or menstrual disturbances during oral contraception.
View Article and Find Full Text PDFManipulation of angiogenesis may have a profound effect on female reproductive function, but this has not yet been demonstrated by direct experiment in species with ovulatory cycles similar to those in women. To investigate whether angiogenesis could be inhibited in the primate corpus luteum, and the consequences of such inhibition on luteal function, marmosets were treated with an antibody to vascular endothelial growth factor (VEGF). Treatment commenced at the time of ovulation and was continued for 3 days (early luteal group) or 10 days (midluteal group).
View Article and Find Full Text PDFObjective: To investigate the role of serum vascular endothelial growth factor (VEGF) in the assessment of patients with prostate cancer. Patients, subjects and methods Serum from 78 men was assayed for VEGF using a commercially available enzyme-linked immunosorbent assay kit. Forty-eight patients had a histopathological diagnosis of prostate cancer (16 local disease, 32 metastatic), nine had benign prostatic hyperplasia (BPH) and 21 were healthy controls.
View Article and Find Full Text PDFThymidine phosphorylase (TP) is a potent angiogenic molecule shown to induce endothelial cell migration and proliferation. We investigated the expression of TP in a series of 156 endometrial carcinomas, using immunohistochemical methods. Histopathological parameters of known prognostic significance and the molecular factors of p53, bcl-2 and angiogenesis were also assessed.
View Article and Find Full Text PDFVascular endothelial growth factor (VEGF) is an important factor mediating tumour angiogenesis. VEGF mRNA is differentially expressed in bladder cancer with high expression in superficial tumours (stage pTa and pT1) contrasting with low expression in muscle invasive tumours (stage > or = pT2). To investigate mechanisms regulating VEGF expression in bladder cancer, VEGF mRNA and protein were measured in normal bladder (n = 12) and primary bladder cancers (n = 57).
View Article and Find Full Text PDFNutrition plays a central role in linking the fields of developmental neurobiology and cognitive neuroscience. It has a profound impact on the development of brain structure and function and malnutrition can result in developmental dysfunction and disease in later life. A number of diseases, including schizophrenia, may be related to neurodevelopmental insults such as malnutrition, hypoxia, viruses or in utero drug exposure.
View Article and Find Full Text PDFExternal fixation is commonly used in the treatment of distal radius fractures. In this in vitro study, we investigated changes in fracture stability when using supplemental radial styloid pinning in combination with external fixation. Eight previously frozen cadaveric upper extremities were mounted in a computer-controlled wrist-loading apparatus.
View Article and Find Full Text PDFNorepinephrine (NE) neurons within the nucleus tractus solitarii (NTS; A2 neurons) and ventrolateral medulla (A1 neurons) represent gonadal steroid-dependent components of several neural networks regulating reproduction. Previous studies have shown that both A1 and A2 neurons express estrogen receptors (ERs). Using double labeling immunocytochemistry we report here that substantial numbers of NE neurons located within the NTS express progesterone receptor (PR) immunoreactivity, whereas few PRs are found in ventrolateral medulla.
View Article and Find Full Text PDFThe aim of this study was to raise and characterize a monoclonal antibody reactive with VEGF (vascular endothelial growth factor) in routinely fixed specimens and to use it to investigate its tissue distribution in normal and pathological specimens. Recombinant VEGF 189 protein was used to raise a monoclonal antibody. The specificity of the antibody was confirmed using COS cells transfected with cDNA coding for VEGF 121, 165 and 189 protein and by western blotting studies.
View Article and Find Full Text PDFPurpose: Vascular endothelial growth factor (VEGF) is a principal growth factor mediating tumor angiogenesis. The high expression of VEGF within bladder tumors is associated with a poor prognosis. We quantified urinary VEGF and determined its potential as a prognostic marker in bladder cancer.
View Article and Find Full Text PDFAlthough it is well recognized that sex-steroids exert both developmental and activational influences on the brain, the cellular and molecular mechanisms underlying their actions are less well understood. Progress is rapid, however, and this paper reviews recent insights gained through manipulation of sex-steroid receptor genes, identification of phenotypes expressing these receptors and how these proteins may also be activated to regulate transcription by ligand-independent pathways. Advances in our understanding of more rapid actions of sex-steroids and the molecular targets involved are also reviewed, as are new studies describing effects on synaptic plasticity and the recent excitement regarding the neuroprotective effects of oestrogen replacement therapy in Alzheimer's disease.
View Article and Find Full Text PDFTransient transfection of COS-1 cells followed by fixation, embedding in paraffin, and immunohistochemistry has identified anti-vascular endothelial growth factor (anti-VEGF) mouse monoclonal antibodies that efficiently immunostain VEGF in paraffin-embedded tissue sections. Immunohistochemical localization of VEGF in 34 specimens of normal human endometrium that had been collected at different stages of the menstrual cycle was then performed. VEGF was present at all stages of the cycle, but both the pattern and the intensity of staining varied.
View Article and Find Full Text PDFAngiogenesis is the term used to describe the formation of new blood vessels from the existing vasculature. In order to attract new vessels, a tissue must release an endothelial-cell chemoattractant. 2-Deoxy-D-ribose is produced in vivo by the catalytic action of thymidine phosphorylase (TP) on thymidine and has recently been identified as an endothelial-cell chemoattractant and angiogenesis-inducing factor.
View Article and Find Full Text PDFAngiogenesis is the formation of new blood vessels from the existing vasculature. Vascular endothelial growth factor (VEGF) is an endothelium-specific angiogenic factor strongly implicated in pathological angiogenesis. In this study, the mRNA and protein expression of the four alternatively spliced VEGF isoforms (121, 165, 189 and 206 amino acids) were examined in normal and malignant breast tissues.
View Article and Find Full Text PDFVascular endothelial growth factor (VEGF) is a potent angiogenic factor implicated in many pathological processes. We investigated the regulation of 4 alternatively spliced isoforms (121, 165, 189 and 206 amino acids) by hypoxia, hypoglycemia, acidity, female reproductive hormones and vitamin D in breast carcinoma cell lines representing different tumor phenotypes. There was a 17-fold difference in total VEGF mRNA expression across the cell lines.
View Article and Find Full Text PDFConsiderable evidence indicates that the microvascular changes observed in psoriasis are a result of angiogenesis. Vascular proliferation is driven by the local production of molecules which have angiogenic activity. Platelet-derived endothelial cell growth factor/thymidine phosphorylase (PDECGF/TP) is a potent angiogenic factor active in in vivo angiogenesis assays and overexpressed in several tumour types.
View Article and Find Full Text PDFTamoxifen is currently the most widely used drug for the treatment of breast cancer, but there now exists considerable evidence that tamoxifen can also induce endometrial hyperplasia in pre menopausal women. We have used PCR differential display on primary human endometrial isolates in an attempt to identify genes induced by tamoxifen but not estrogen. Eight such differentially expressed bands were cloned and sequenced, one of which was found to be the peptide adrenomedullin.
View Article and Find Full Text PDFThe tumor vasculature offers a target for anti-cancer gene therapy which has the advantages both of good accessibility to systemically delivered therapy and comparative homogeneity across solid tumor types. We aimed to develop retroviruses carrying endothelial-specific promoters for the delivery of genes to proliferating endothelial cells in vitro and to tumor endothelial cells in vivo. This paper reports the generation of such retroviral vectors and the level of expression of murine tumor necrosis factor-alpha (mTNF-alpha) cDNA following infection into endothelial cells and stromal fibroblasts.
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