Vascular endothelial growth factor (VEGF) is an endothelial cell-specific mitogen in vitro and an angiogenic inducer in a variety of in vivo models. Hypoxia has been shown to be a major inducer of VEGF gene transcription. The tyrosine kinases Flt-1 (VEGFR-1) and Flk-1/KDR (VEGFR-2) are high-affinity VEGF receptors. The role of VEGF in developmental angiogenesis is emphasized by the finding that loss of a single VEGF allele results in defective vascularization and early embryonic lethality. VEGF is critical also for reproductive and bone angiogenesis. Substantial evidence also implicates VEGF as a mediator of pathological angiogenesis. In situ hybridization studies demonstrate expression of VEGF mRNA in the majority of human tumors. Anti-VEGF monoclonal antibodies and other VEGF inhibitors block the growth of several tumor cell lines in nude mice. Clinical trials with various VEGF inhibitors in a variety of malignancies are ongoing. Very recently, an anti-VEGF monoclonal antibody (bevacizumab; Avastin) has been approved by the Food and Drug Administration as a first-line treatment for metastatic colorectal cancer in combination with chemotherapy. Furthermore, VEGF is implicated in intraocular neovascularization associated with diabetic retinopathy and age-related macular degeneration.

/pdf/vascular-endothelial-growth-factor-basic-science-and-17gyy6h97s.pdf

Vascular endothelial growth factor: basic science and clinical progress.

The existence of factors that stimulate blood vessel growth, thereby recruiting a neovascular supply to nourish a growing tumour, was postulated many decades ago, although the identification and isolation of these factors proved elusive. Now, vascular endothelial growth factor (VEGF), which was identified in the 1980s, is recognized as an essential regulator of normal and abnormal blood vessel growth. In 1993, it was shown that a monoclonal antibody that targeted VEGF results in a dramatic suppression of tumour growth in vivo, which led to the development of bevacizumab (Avastin; Genentech), a humanized variant of this anti-VEGF antibody, as an anticancer agent. The recent approval of bevacizumab by the US FDA as a first-line therapy for metastatic colorectal cancer validates the ideas that VEGF is a key mediator of tumour angiogenesis and that blocking angiogenesis is an effective strategy to treat human cancer.

Discovery and development of bevacizumab, an anti-VEGF antibody for treating cancer

The most common human cancers --lung, breast and prostate -- have a great avidity for bone, leading to painful and untreatable consequences. What makes some cancers, but not others, metastasize to bone, and how do they alter its physiology? Some of the molecular mechanisms that are responsible have recently been identified, and provide new molecular targets for drug development.

http://helsenet.info/pdf/metastasis/1.pdf

Metastasis to bone: causes, consequences and therapeutic opportunities

The lipocalin protein family is a large group of small extracellular proteins. The family demonstrates great diversity at the sequence level; however, most lipocalins share three characteristic conserved sequence motifs, the kernel lipocalins, while a group of more divergent family members, the outlier lipocalins, share only one. Belying this sequence dissimilarity, lipocalin crystal structures are highly conserved and comprise a single eight-stranded continuously hydrogen-bonded antiparallel beta-barrel, which encloses an internal ligand-binding site. Together with two other families of ligand-binding proteins, the fatty-acid-binding proteins (FABPs) and the avidins, the lipocalins form part of an overall structural superfamily: the calycins. Members of the lipocalin family are characterized by several common molecular-recognition properties: the ability to bind a range of small hydrophobic molecules, binding to specific cell-surface receptors and the formation of complexes with soluble macromolecules. The varied biological functions of the lipocalins are mediated by one or more of these properties. In the past, the lipocalins have been classified as transport proteins; however, it is now clear that the lipocalins exhibit great functional diversity, with roles in retinol transport, invertebrate cryptic coloration, olfaction and pheromone transport, and prostaglandin synthesis. The lipocalins have also been implicated in the regulation of cell homoeostasis and the modulation of the immune response, and, as carrier proteins, to act in the general clearance of endogenous and exogenous compounds.

/pdf/the-lipocalin-protein-family-structure-and-function-lbmezfltm1.pdf

The lipocalin protein family: structure and function

Publisher Summary The fibroblast growth factors (FGFs) constitute a family of closely related polypeptide mitogens There are seven members of this family, identified on the basis of amino acid sequence homologies The FGF family has distinguished itself from other growth factor families by virtue of the pleiotropic actions of its members This chapter discusses the structural and functional diversity in the FGF receptor multigene family The effects of FGFs are known to be mediated by high-affinity receptor tyrosine kinases The structurally diverse receptor molecules are also functionally different The characterization of structural and functional diversity within the FGF receptor shows the differences in the mechanisms of action among members of the FGF family The first members of the FGF family to be purified and characterized were acidic FGF (aFGF) and basic FGF (bFGF), which are purified on the basis of their mitogenicity toward fibroblasts by using bovine pituitary Functional differences among the different receptor forms are observed in the chapter at two levels The long-range goal of designing the effective agonist and antagonists of FGF action has considerable therapeutic value

Structural and Functional Diversity in the FGf Receptor Multigene Family

Two monoclonal antibodies (mAbs) against bovine heparin-binding growth factor II (HBGF-II)/basic fibroblast growth factor (bFGF) were obtained from mouse hybridoma cell lines. They were highly specific for bFGF from bovine, human, and mouse sources and did not cross-react with bovine heparin-binding growth factor I (HBGF-I)/acidic fibroblast growth factor (aFGF). The immunoglobulin class and subclass of these mAbs were IgG1, K. The apparent dissociation constant (Kd) for bFGF of these mAbs ranged from 10(-9) to 10(-10) M. One mAb (bFM-2) also cross-reacted with heat-inactivated bFGF, while the other mAb (bFM-1) did not, suggesting that bFM-1 recognized the conformation of the bFGF molecule necessary for its biological activity. These mAbs inhibited growth of cultured bovine capillary endothelial cells in both the presence and absence of exogenous bFGF, indicating the autocrine action of this growth factor in in vitro growth of these cells. On the other hand, injection of these hybridoma cell lines s.c. into the backs of athymic mice resulted in development of highly vascularized solid tumors and a sustained high level of anti-bFGF activity in the blood of the tumor-bearing mice. These findings suggest that bFGF is not essential as an autocrine or paracrine growth factor for angiogenesis in vivo. These mAbs should be useful in further studies on the physiological role and the conformation-function relationship of bFGF because they block its biological activity.

Monoclonal antibodies against heparin-binding growth factor II/basic fibroblast growth factor that block its biological activity: invalidity of the antibodies for tumor angiogenesis

Expression and immunochemical analysis of rat and human fibroblast growth factor receptor (flg) isoforms.

Probasin, a rat prostatic protein, is statistically related to members of a protein family that includes serum, cellular, and nuclear proteins. In vivo, probasin appears both in the secretions and in the nucleus of prostatic epithelial cells. Using primer extension and S1 nuclease protection assays we detected only one probasin mRNA. Thus, the localization of this protein to two separate cellular regions must be encoded by this one mRNA. Furthermore, in vitro translation of synthetic probasin mRNA demonstrated that a protein containing a signal peptide and a protein lacking a signal peptide were synthesized by initiation at different AUG codons. These data are consistent with a mechanism of translational regulation of a eukaryotic bifunctional mRNA.

Regulation of a bifunctional mRNA results in synthesis of secreted and nuclear probasin.

The rat prostate contains two types of growth factors capable of stimulating DNA synthesis in BALB/3T3 cells. These rat prostatic growth factors (RPGF) were separable by a different affinity for heparin: low affinity type RPGF and high affinity (HiA) type RPGF. About 80% of the RPGF in the cytosol from normal prostates was low affinity type, whereas more than 80% in the cytosol from the Dunning tumors was HiA type. Elution profile of HiA-RPGF showed two peaks of activity eluted from the heparin-Sepharose column, one at 1.3-1.4 M NaCl (HiA1-RPGF) and the other at 1.6-1.7 M NaCl (HiA2-RPGF). HiA2-RPGF could be purified 1100-fold from the Dunning tumor (AT-3 subline) in about 20% recovery by heparin-Sepharose chromatography. The partially purified HiA2-RPGF in the Dunning tumor has a molecular weight of about 19,000 and isoelectric point of about 3.8, and stimulated DNA synthesis at a concentration of about 0.25 nM. The activity was lost by heat treatment at 70 degrees C for 5 min and by acid treatment, whereas it was stimulated by incubating with dithiothreitol. The HiA2-RPGF did not have transforming growth factor activity at a concentration of 250 ng/ml or lower in the presence of epidermal growth factor.

Heparin binding affinity of rat prostatic growth factor in normal and cancerous prostates: partial purification and characterization of rat prostatic growth factor in the Dunning tumor.

The present invention relates to a method for assaying soluble APP, comprising using an antibody against amyloid β protein (Aβ) or amyloid precursor protein (APP). 
In accordance with the present invention, soluble APP can be accurately assayed. Additionally, an assay system composed of a monoclonal antibody recognizing the N-terminus of Aβ and a monoclonal antibody recognizing soluble APP in combination can definitely diagnose the presence or absence of Alzheimer disease.

Yuhsi Matuo

Papers

Monoclonal antibodies against heparin-binding growth factor II/basic fibroblast growth factor that block its biological activity: invalidity of the antibodies for tumor angiogenesis

Expression and immunochemical analysis of rat and human fibroblast growth factor receptor (flg) isoforms.

Regulation of a bifunctional mRNA results in synthesis of secreted and nuclear probasin.

Heparin binding affinity of rat prostatic growth factor in normal and cancerous prostates: partial purification and characterization of rat prostatic growth factor in the Dunning tumor.

Method for assaying soluble amyloid precursor protein