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Query: UMLS:C0027819 (
neuroblastoma
)
27,800
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Human insulin-like growth factor I and II (
IGF-I
and IGF-II) in concentrations of 1-30 ng/ml, were shown to stimulate ornithine decarboxylase activity and [3H]thymidine incorporation in human SH-SY5Y
neuroblastoma
cells. Proliferation of these cells was also stimulated by
IGF-I
and II when added to RPMI 1640 medium, fortified with selenium, hydrocortisone, transferrin, and beta-estradiol. Labeled
IGF-I
and II bound to SH-SY5Y cells. The cross-reaction pattern of
IGF-I
, IGF-II, and insulin in competing with the binding of labeled
IGF-I
and IGF-II, respectively, indicated that SH-SY5Y cells express both type I and type II IGF receptors. Treatment of SH-SY5Y cells for 4 d with 12-O-tetradecanoylphorbol-13-acetate (TPA), which resulted in morphological and functional differentiation and growth inhibition, abolished the mitogenic response to both
IGF-I
and II. Concomitantly, the binding of IGF-II disappeared almost totally, which offers a possible explanation for the reduced biological response to IGF-II after TPA treatment. In contrast, the
IGF-I
binding in TPA-treated cells was only reduced to approximately 70% of the binding to control cells. It is therefore not excluded that the IGF-I receptor could be uncoupled by TPA, with persistent binding capacity for
IGF-I
.
...
PMID:Mitogenic response of human SH-SY5Y neuroblastoma cells to insulin-like growth factor I and II is dependent on the stage of differentiation. 300 92
The functional role of brain insulin and insulinlike growth factor (IGF) receptors is being sought. Recently it has been found that these ligands are members of a newly identified family of neuritogenic polypeptides. We studied the relationship between 125I-insulin and 125I-IGF binding and their capacity to enhance neurite formation in cultured human
neuroblastoma
SH-SY5Y cells. The binding of 125I-insulin was temperature-dependent and heterogeneous. The Scatchard plot and dissociation rate were both consistent with the presence of two types of sites. There appeared to be about 900 high affinity sites per cell with a Kd of about 3 nM. This compared favorably with the half-maximal concentration of 4 nM for enhancement of neurite formation. The type I IGF sites were also present. Physiologic concentrations of insulin clearly enhanced neurite formation through the insulin sites, whereas physiologic concentrations of
IGF-I
and IGF-II enhanced through the IGF sites. Cross-occupancy of sites was observed at supraphysiologic concentrations, providing a reasonable explanation for the broad dose-response curves for these ligands. These results support the suggestion that one function of insulin and IGF receptors in neural tissues may be to modulate neurite formation.
...
PMID:Insulin and insulinlike growth factor receptors regulating neurite formation in cultured human neuroblastoma cells. 328 62
Phorbolester-triggered differentiation of SH-SY5Y
neuroblastoma
cells requires serum and a prolonged activation of protein kinase C (PKC). Under serum-free conditions development of a mature phenotype requires phorbolester in combination with a member of either the insulin-like growth factor (IGF) or the platelet-derived growth factor family. Here we report that basic and acidic fibroblast growth factor (FGF) and epidermal growth factor, but not nerve growth factor, synergistically potentiate phorbolester-induced differentiation. Alone these factors induced a mitogenic response which varied in magnitude, with basic FGF and
IGF-I
being the two most potent mitogens. However, a combination of basic FGF and
IGF-I
induced differentiation as judged by morphology and the increase in growth associated protein (GAP-43) and neuropeptide tyrosine mRNA levels. In contrast to the phenotype obtained in the presence of phorbolester, bFGF and
IGF-I
-treated SH-SY5Y cells retained their capacity to proliferate. Finally, in these cells, the phosphorylation of the endogenous PKC substrate, myristoylated alanine-rich C-kinase substrate (MARCKS), was slightly increased during several days, suggesting an involvement of PKC in the bFGF and
IGF-I
-induced differentiation.
...
PMID:Basic FGF and IGF-I promote differentiation of human SH-SY5Y neuroblastoma cells in culture. 751 11
Insulin-like growth factors (IGFs) regulate the autocrine/paracrine growth of neuroblastomas. The IGFs bind to specific binding proteins (IGFBPs) which modulate their biological activity. We investigated, by Western ligand blotting (WLB), the presence of IGFBPs and their possible modulation by retinoic acid (RA),
IGF-I
, IGF-II and truncated Des(1-3)
IGF-I
in conditioned medium (CM) of the human
neuroblastoma
SK-N-BE(2) cell line. We demonstrated the presence of two IGFBPs, with MW 37 kDa and 25 kDa. Following immunoprecipitation, they turned out to be IGFBP-2 and -4, respectively. The RA-induced differentiation in SK-N-BE(2) cells was accompanied by a marked reduction of the intensity of both IGFBP bands after 48 h (32% and 24% of control, respectively) and 72 h (2% and 0% of control, respectively) incubation. The addition of exogenous IGFs, which did not induce cell differentiation, did not change the IGFBP pattern significantly, except for the truncated form of
IGF-I
, which induced a marked decrease in both the 37 kDa and 25 kDa bands after 72 h incubation (45% and 18% of control, respectively). These findings suggest that IGFBPs have a role in RA-induced differentiation in human
neuroblastoma
cells.
...
PMID:Expression and down-regulation by retinoic acid of IGF binding protein-2 and -4 in medium from human neuroblastoma cells. 752 70
The human
neuroblastoma
line, SK-N-SH, has been subcloned into SH-SY5Y, a neuroblast N cell line, and SH-EP, an epithelial Schwann S cell line. We have previously shown that SH-SY5Y
neuroblastoma
cells produce insulin-like growth factor II (IGF-II), which acts by an autocrine mechanism to stimulate cell growth. In the current study, we examined the effect of IGF-II on SH-EP
neuroblastoma
cells. Northern blot and reverse transcriptase-polymerase chain reaction analyses indicate that SH-EP cells do not produce
IGF-I
or IGF-II but express the type I and type II IGF receptors (IGF-IR and IGF-IIR). Cell surface expression of IGF-IR, assessed by fluorescence-activated sorting, was lower in SH-EP cells than in SH-SY5Y cells. Immunoprecipitation of IGF-IR, followed by anti-phosphotyrosine or anti-IGF-IR immunoblotting, demonstrated functional expression of these receptors in both cell types and confirmed the lower level of IGF-IR expression in SH-EP cells. IGF-II promoted SH-EP cell growth in the presence of low concentrations of calf serum (0.1-0.3%) or 10 ng/ml epidermal growth factor (EGF). IGF-II stimulation of SH-EP growth was eliminated by the IGF-IR blocking antibody (alpha IR-3) but not by an IGF-IIR blocking antibody. Stimulation of cell growth via this receptor was also indicated by the ligand specificity for IGF analogs and insulin (IGF-II approximately
IGF-I
approximately des(1-3)
IGF-I
>> insulin). These results indicate that in the presence of a permissive factor such as calf serum or EGF, IGF-II stimulates SH-EP cell growth via the IGF-IR. Collectively, these data suggest that within primary neuroblastomas, IGF-II may act as a paracrine factor to contribute to the promotion of S cell growth.
...
PMID:Insulin-like growth factor-II as a paracrine growth factor in human neuroblastoma cells. 758 43
Insulin-like growth factor (IGF)-binding proteins (BPs) bind
IGF-I
and IGF-II with high affinity and modify the activity of IGF peptides in a complex manner. We have characterized the affinities of IGFBP-1-4 for
IGF-I
and -II by employing 1) purified IGFBP preparations, 2) both [125I]
IGF-I
and [125I]IGF-II as radioligands, and 3) multiple IGF analogs designed to have altered affinities for IGFBPs. To this end, human (h) IGFBP-1, hIGFBP-2, and rat (r) IGFBP-4 have been purified to homogeneity from human amniotic fluid, human prostate epithelial cell culture, and B104 rat
neuroblastoma
cells; for human IGFBP-3, the glycosylated recombinant form (rec-hIGFBP-3), produced in Chinese hamster ovary cells, was employed. The IC50 values of
IGF-I
for hIGFBP-1, hIGFBP-2, rec-hIGFBP-3, rIGFBP-4, and human serum IGFBPs were 0.05 +/- 0.01, 5.0 +/- 0.01, 0.25 +/- 0.20, 0.6 +/- 0.4, and 0.1 +/- 0.01 ng/ml, respectively. While hIGFBP-1 and rIGFBP-4 had virtually equivalent affinities for
IGF-I
and IGF-II, hIGFBP-2 and rec-hIGFBP-3 demonstrated 2- to 5-fold higher affinities for IGF-II than for
IGF-I
. Studies with [Gln3,Ala4,Tyr15,Leu16]
IGF-I
and Des-(1-3)-
IGF-I
indicate that specific residues in the first 16 amino acids of the B domain of
IGF-I
appear to be critical for binding to all of the IGFBPs tested, but not to IGF receptors. However, severe modifications in the B domain disrupt binding affinity, not only for IGFBPs, but also for receptors (
IGF-I
/insulin hybrid and B-chain mutant). Interestingly, modifications in the A domain of
IGF-I
, which is believed to contain residues critical for binding to
IGF-I
and insulin receptors, show differential effects on binding affinity to BPs. [Thr49,Ser50,Ile51]
IGF-I
, which has normal affinity for the type I IGF receptor, shows at least a 500-fold decreased affinity for hIGFBP-1 and recombinant hIGFBP-3, in contrast to 50- to 100-fold reduced affinity for hIGFBP-2 and rIGFBP-4, and 5- to 10-fold reduced affinity for purified human serum IGFBP-3. More significantly, [1-27,Gly4,38-70]
IGF-I
shows a 30-fold decreased affinity for the type I IGF receptor and 10- and 2.5-fold reduced affinities for hIGFBP-1 and rec-hIGFBP-3, respectively, but no reduction in affinity for hIGFBP-2 or rIGFBP-4.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Characterization of the affinities of insulin-like growth factor (IGF)-binding proteins 1-4 for IGF-I, IGF-II, IGF-I/insulin hybrid, and IGF-I analogs. 767 79
The 3-5 year survival rates of patients with disseminated Ewing's sarcoma (ES) or the closely related peripheral primitive neuroectodermal tumors (PNET) remain low, even under aggressive treatment involving highly toxic multidrug chemotherapeutic regimens. ES and PNET are sensitive to doxorubicin, but may escape treatment by expression of the multidrug-resistant phenotype and/or other mechanisms. In this study, we have identified albumin as growth supporting factor for ES and PNET cells in
IGF-I
-supplemented serum-free tissue culture medium. To investigate the specificity and toxicity of albumin-based drug conjugates, doxorubicin was coupled to bovine serum albumin (BSA) by either a two step glutaraldehyde or carbodiimide-C4-spacer technique, yielding monomeric DOX-albumin conjugates with conjugation numbers ranging from 3-20 moles DOX/mole BSA. Cellular uptake of fluorescein-isothiocyanate-(FITC)-labeled albumin and DOX-albumin conjugates could be demonstrated by flow cytometric measurements of cell-associated fluorescence and confocal microscopy. The cytostatic activity of these conjugates against ES/PNET cell lines, a
neuroblastoma
(LAN-1) and prostate cancer carcinoma cell line (PC-3) and normal lymphoblasts was tested in short-term proliferation assays (48 h). The results show a high selectivity of the DOX-albumin conjugates for ES/PNET cell lines, with highest growth inhibition by conjugates with low DOX conjugation numbers (n = 3) in serum-supplemented medium (17-32 fold loss of activity compared to free DOX), followed by 20-DOX-C4-albumin in serum-free medium and low activity of the other conjugates. In conclusion, DOX-albumin conjugates inhibit the growth of ES/PNET cell lines selectively, showing low activity against the unrelated carcinoma line PC-3 and sparing normal lymphoblasts. The inverse correlation of activity and conjugation number demonstrates a low cytotoxic activity of DOX in acid-stable binding to monomeric albumin, pointing to a selective cytostatic activity of the modified albumin against ES and PNET cells, even in the presence of a 100 fold excess of unmodified serum albumin.
...
PMID:In vitro antiproliferative effects of albumin-doxorubicin conjugates against Ewing's sarcoma and peripheral neuroectodermal tumor cells. 784 32
The
neuroblastoma
cell line SK-ER3, which is stably transfected with the estrogen receptor (ER), was used to study the effect of insulin and insulin-like growth factors (
IGF-I
and IGF-II) on growth and morphological differentiation induced by estrogens. The data demonstrate that insulin and related growth factors control the growth and morphological differentiation of the cell line expressing the ER, but not of the parental cell line. Effects elicited by the growth factors in SK-ER3 cells can be blocked by ER antagonists. Transient transfection studies further confirm an effect of the IGFs in modulation of ER-activated promoters. The results presented support the hypothesis of the existence of cross-talk between membrane and intracellular receptors and provide evidence for physiological consequences of the activation of such a pathway of communication. The present study is of particular interest with regard to the theory of prenatal involvement of the ER in maturation of nerve cells. It could, in fact, be hypothesized that
IGF-I
and IGF-II, present in high concentrations in the developing brain, might activate the ER expressed in several embryonic brain nuclei.
...
PMID:Insulin-like growth factors activate estrogen receptor to control the growth and differentiation of the human neuroblastoma cell line SK-ER3. 798 52
Human
neuroblastoma
SH-SY5Y cell is a cloned cell line which has many attractive features for the study of neuronal proliferation and neurite outgrowth, because it has receptors for insulin,
IGF-I
and PDGF. Gangliosides are sialic acid containing glycosphingolipids which form an integral part of the plasma membrane of many mammalian cells. They inhibit cell growth mediated by tyrosine kinase receptors and ligand-stimulated tyrosine kinase activity, and autophosphorylation of EGF(epidermal growth factor) and PDGF receptors. The experiment was designed to study the effects of GM1 ganglioside on growth of human
neuroblastoma
SH-SY5Y cells stimulated with trophic factor in vitro. The cells were plated in Eagle's minimum essential medium without serum. The number and morphologic change of SH-SY5Y cells were evaluated in the serum free medium added GM1 ganglioside with insulin or PDGF. SH-SY5Y cells were maintained for six days in serum-free medium, and then cultured for over two weeks in serum-free medium containing either insulin or PDGF. The effect of insulin on cell proliferation developed earlier and was more potent than that of PDGF. These proliferative effects were inhibited by GM1 ganglioside, and the cells showed prominent neurites outgrowth. These findings suggest that GM1 ganglioside inhibits the cell proliferation mediated by tyrosine kinase receptors and directly induces neuritogenesis as one of the neurotrophic factors.
...
PMID:The biologic role of ganglioside in neuronal differentiation--effects of GM1 ganglioside on human neuroblastoma SH-SY5Y cells. 798 93
Insulin-like growth factors (
IGF-I
and IGF-II) are mitogenic polypeptides expressed in both developing and adult tissues. To examine the effects of IGFs on neuronal growth, we used SH-SY5Y
neuroblastoma
cells as an in vitro model of nervous system development. In the current study, we found that either
IGF-I
(0.1 to 10 nM), insulin (0.1 to 5 micrograms/ml) or calf serum (0.1 to 3%) increased SH-SY5Y proliferation over a 3 day period in a dose dependent manner. In each case, treatment with anti-IGF-I receptor antibodies blocked cell proliferation. IGF-II mRNA levels correlated with SH-SY5Y cell density; subconfluent cells expressed high levels of IGF-II mRNA while low levels of IGF-II mRNA were present in confluent cells. Similarly, serum deprivation increased IGF-I receptor mRNA by 4-fold. Collectively, these results support the concept that an IGF/IGF-I receptor system at least partially mediates SH-SY5Y cell proliferation and suggests the importance of IGFs in regulating neuronal growth.
...
PMID:Effects of serum and insulin-like growth factors on human neuroblastoma cell growth. 826 10
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