Insulin-like growth factor binding protein 1 expression inhibits insulin-like growth factor I action in MCF-7 breast cancer cells.

Interactions between insulin-like growth factor I (IGF-I) and the type of I IGF receptor may be affected by high-affinity extracellular binding proteins. To date, six distinct IGF binding proteins (IGFBPs) have been identified, but their physiological roles are not well understood. For example, depending on experimental conditions, IGFBP-1 has been shown to both enhance and inhibit IGF-I mediated mitogenesis.

Genetic deletion of a neural cell adhesion molecule variant (N-CAM-180) produces distinct defects in the central nervous system.

N-CAM is abundantly expressed in the nervous system in the form of numerous structural variants with characteristic distribution patterns and functional properties. N-CAM-180, the variant having the largest cytoplasmic domain, is expressed by all neurons. The N-CAM-180-specific exon 18 has been deleted to generate homozygous mice unable to express this N-CAM form.

In vitro sensitivity testing of human bladder cancers and cell lines to TP-40, a hybrid protein with selective targeting and cytotoxicity.

TP-40 is a hybrid fusion protein produced by recombinant technology and consists of a molecule of transforming growth factor-alpha (TGF-alpha) fused to the Pseudomonas exotoxin PE-40. A panel of human and murine bladder cancer cell lines was found to be universally sensitive in vitro to TP-40 in a clonogenic assay. All lines expressed receptor for epidermal growth factor (EGF), though none demonstrated gene amplification for the EGF receptor.

Recombinant insulin-like growth factor binding protein-1 inhibits IGF-I, serum, and estrogen-dependent growth of MCF-7 human breast cancer cells.

The insulin-like growth factors (IGFs) are potent mitogens for breast cancer cells and their activity is modulated by high affinity binding proteins (IGFBPs). We have recently shown that IGFBP-1 purified from human amniotic fluid neutralizes IGF-I-dependent growth of MCF-7 cells. In this study we examined the effects of recombinant IGFBP-1 (rBP-1) on IGF-I, estradiol (E2), and serum-induced monolayer and anchorage independent growth (AIG) of MCF-7 cells.

Development of predictive models of laboratory animal growth using artificial neural networks.

Traditional regression analysis of body weight growth curves encounters problems when the data are extremely variable. While transformations are often employed to meet the criteria of the analysis, some transformations are inadequate for normalizing the data. Regression analysis also requires presuppositions regarding the model to be fit and the techniques to be used in the analysis.

Development of polyclonal antibodies against angiotensin type 2 receptors.

Murine neuroblastoma N1E-115 cells are a useful system in which to study neuronal angiotensin II (AngII) receptors. N1E-115 cells possess both type 1 (AT1) and type 2 (AT2) AngII receptor subtypes, as does mammalian brain. AT2 receptors in brain or N1E-115 cells can be solubilized in 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulfonate.

Families and the structural relatedness among globular proteins.

Protein structures come in families. Are families "closely knit" or "loosely knit" entities? We describe a measure of relatedness among polymer conformations. Based on weighted distance maps, this measure differs from existing measures mainly in two respects: (1) it is computationally fast, and (2) it can compare any two proteins, regardless of their relative chain lengths or degree of similarity.

Expression of insulin-like growth factor binding proteins in human breast cancer correlates with estrogen receptor status.

The insulin-like growth factors (IGFs) have been implicated in the growth regulation of human breast cancer. Since the IGFs are associated with specific binding proteins (IGFBPs) which may modulate receptor/ligand interactions, production of IGFBPs by breast cancer cells could alter their IGF-dependent growth. This study examined the expression of IGFBPs 4, 5, and 6 in eight breast cancer cell lines (BCCLs) using ribonuclease (RNase) protection assays.

The effect of neurocatin on protein phosphorylation in striatal synaptosomes from rat brain.

Neurocatin, a neuroregulatory factor isolated from mammalian brain, is a powerful affector of protein phosphorylation in rat striatal synaptosomes. Two major synaptosomal phosphoproteins of approximately 80 and approximately 60 kDa, possibly synapsin I and tyrosine hydroxylase, were especially sensitive to neurocatin. Immunoprecipitation experiments confirmed that the 60-kDa protein is the enzyme tyrosine hydroxylase.

Prognostic indicators in early breast cancer.

Approximately 115,000 new cases of axillary node negative breast cancer were diagnosed in this country last year. Since about 20-30% of these patients will ultimately relapse and die of their disease, adjuvant systemic therapy has been advocated for this group to decrease the relapse rate and prolong survival. However, although most clinical trials have demonstrated a modest impact on disease recurrence, the available data have failed to show consistent improvements in overall survival and does not justify the generalized use of systemic treatment in this patient subgroup.

Phase II trial of 13-cis-retinoic acid plus interferon-alpha in recurrent head and neck cancer.

13-cis-retinoic acid (isotretinoin) and interferon-alpha have limited activity as single agents in advanced cancer. Preclinical data indicate that these agents have different mechanisms of action and, in combination have greater activity (that is, the ability to modulate growth and differentiation) in a number of malignant cell types than either agent alone. In clinical trials, the new biological regimen of 13-cis-retinoic acid and interferon-alpha was shown to have major activity in advanced squamous cell carcinoma of the skin and cervix.

Effect of endocrine therapy on growth of T61 human breast cancer xenografts is directly correlated to a specific down-regulation of insulin-like growth factor II (IGF-II).

Insulin-like growth factors I and II (IGF-I and IGF-II) are potent mitogens for some human breast cancer cell lines, and expression of IGF-II mRNA in the oestrogen receptor-positive (ER+) and oestradiol (E2) stimulated human breast cancer cell line T47D is increased by E2, suggesting a role for IGF-II in the mitogenic response to E2. Very little information is available from the literature on the relation between growth inhibition by endocrine therapy and cellular production of IGF-II. Here we report on the effect of E2 and tamoxifen (TAM) on IGF-II mRNA and protein expression in the ER+T61 human breast cancer xenograft.

Regulation of insulin-like growth factor binding proteins in ovarian cancer cells by oestrogen.

Insulin-like growth factor-I (IGF-I), its receptor and its binding proteins are expressed by ovarian cancer cells. In this study, we examined oestradiol (E2) regulation of IGF-I and IGF binding proteins (IGFBP) in an oestrogen-responsive ovarian cancer cell line, PE04. In serum-free conditions, PE04 cell monolayer growth was increased 1.

Gene expression of the insulin-like growth factors and their receptors in human neuroblastoma cell lines.

Insulin-like growth factors (IGF) I and II are polypeptides with both growth-promoting and insulin-like metabolic effects. The developmentally specific expression of IGF I and II in the nervous system implies a role for these growth factors in neuronal growth and differentiation. In the present study, we analyzed IGF and IGF receptor mRNA transcripts from two related human neuroblastoma cell lines, SH-SY5Y and SK-N-SH.

Regulation of insulin-like growth factor-binding protein (IGFBP) expression by breast cancer cells: use of IGFBP-1 as an inhibitor of insulin-like growth factor action.

Background: The insulin-like growth factors (IGFs) play an important role in normal growth and development. Evidence suggests they may also regulate the growth of several cancer cell types. This regulation is mediated by interactions between the receptors and ligands.

Development of a computerized database for the study of anaesthesia care.

To record, tabulate and report problems associated with anaesthesia, we have developed an information collection system and computer software to follow all patients attended by an anaesthetist at a teaching hospital in Canada. For the last 15 mo, data for 17,000 patients have been collected and the system is ongoing. Data collection is from three sources: carbonless copies of the handwritten Operating Room (OR) and Post Anaesthetic Care Unit (PACU) records, other hospital databases, and postoperative visits.

Health care access and advocacy for immigrant and other underserved elders.

Little is known about health care access and advocacy for elders of color, and even less is known about immigrant elders, whose growing number is the major reason that almost one of every three older persons in the U.S. by the year 2050 will be an elder of color.

Can the insulin-like growth factors regulate breast cancer growth?

Many laboratories have demonstrated that polypeptide growth factors stimulate human cancer cell growth in experimental systems. Despite this observation, a central question remains: can inhibition of peptide growth factor action inhibit tumor growth in humans? To answer this question, several other concerns must first be addressed. Which growth factors are critical for tumor growth? What are the specific cellular effectors for each growth factor? Can feasible therapies be designed to interrupt growth factor pathways? This issue of Breast Cancer Research and Treatment explores the relevance of the insulin-like growth factors to breast cancer cell growth.

The insulin-like growth factor binding proteins (IGFBPs) in human breast cancer.

Several lines of evidence suggest that IGFs are important regulators of breast cancer cell growth. Unlike other growth factors, the IGFs interact with specific binding proteins in all extracellular fluids. To date, six different IGFBPs have been cloned, although their exact physiological function is not understood.

The insulin-like growth factor family of ligands, receptors, and binding proteins.

The insulin-like growth factors (IGFs) have important roles in normal cellular growth and development. The IGFs have also been implicated in regulation of tumor cell growth. Two ligands, IGF-I and IGF-II, have been identified that are expressed in both fetal and adult tissues.

Gene expression of the insulin-like growth factors and their receptors in cultured human retinal pigment epithelial cells.

Insulin-like growth factors I and II (IGF I and II) are polypeptides with both growth-promoting and insulin-like metabolic effects. Immunoreactive IGF I is present in the retina and both IGF I and II are present in vitreal fluid. The type I and type II IGF receptors are also localized within the neural retina.